hub.c 163.3 KB
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/*
 * USB hub driver.
 *
 * (C) Copyright 1999 Linus Torvalds
 * (C) Copyright 1999 Johannes Erdfelt
 * (C) Copyright 1999 Gregory P. Smith
 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
 *
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/completion.h>
#include <linux/sched.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/ioctl.h>
#include <linux/usb.h>
#include <linux/usbdevice_fs.h>
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#include <linux/usb/hcd.h>
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#include <linux/usb/otg.h>
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#include <linux/usb/quirks.h>
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#include <linux/kthread.h>
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#include <linux/mutex.h>
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#include <linux/freezer.h>
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#include <linux/random.h>
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#include <linux/pm_qos.h>
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#include <asm/uaccess.h>
#include <asm/byteorder.h>

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#include "hub.h"
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#include "otg_whitelist.h"
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#define USB_VENDOR_GENESYS_LOGIC		0x05e3
#define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND	0x01

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/* Protect struct usb_device->state and ->children members
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 * Note: Both are also protected by ->dev.sem, except that ->state can
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 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
static DEFINE_SPINLOCK(device_state_lock);

/* khubd's worklist and its lock */
static DEFINE_SPINLOCK(hub_event_lock);
static LIST_HEAD(hub_event_list);	/* List of hubs needing servicing */

/* Wakes up khubd */
static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);

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static struct task_struct *khubd_task;
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/* synchronize hub-port add/remove and peering operations */
DEFINE_MUTEX(usb_port_peer_mutex);

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/* cycle leds on hubs that aren't blinking for attention */
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static bool blinkenlights = 0;
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module_param (blinkenlights, bool, S_IRUGO);
MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");

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/*
 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
 * 10 seconds to send reply for the initial 64-byte descriptor request.
 */
/* define initial 64-byte descriptor request timeout in milliseconds */
static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
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MODULE_PARM_DESC(initial_descriptor_timeout,
		"initial 64-byte descriptor request timeout in milliseconds "
		"(default 5000 - 5.0 seconds)");
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/*
 * As of 2.6.10 we introduce a new USB device initialization scheme which
 * closely resembles the way Windows works.  Hopefully it will be compatible
 * with a wider range of devices than the old scheme.  However some previously
 * working devices may start giving rise to "device not accepting address"
 * errors; if that happens the user can try the old scheme by adjusting the
 * following module parameters.
 *
 * For maximum flexibility there are two boolean parameters to control the
 * hub driver's behavior.  On the first initialization attempt, if the
 * "old_scheme_first" parameter is set then the old scheme will be used,
 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
 * is set, then the driver will make another attempt, using the other scheme.
 */
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static bool old_scheme_first = 0;
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module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(old_scheme_first,
		 "start with the old device initialization scheme");

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static bool use_both_schemes = 1;
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module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(use_both_schemes,
		"try the other device initialization scheme if the "
		"first one fails");

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/* Mutual exclusion for EHCI CF initialization.  This interferes with
 * port reset on some companion controllers.
 */
DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);

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#define HUB_DEBOUNCE_TIMEOUT	2000
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#define HUB_DEBOUNCE_STEP	  25
#define HUB_DEBOUNCE_STABLE	 100

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static int usb_reset_and_verify_device(struct usb_device *udev);

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static inline char *portspeed(struct usb_hub *hub, int portstatus)
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{
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	if (hub_is_superspeed(hub->hdev))
		return "5.0 Gb/s";
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	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
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		return "480 Mb/s";
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	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
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		return "1.5 Mb/s";
	else
		return "12 Mb/s";
}

/* Note that hdev or one of its children must be locked! */
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struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
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{
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	if (!hdev || !hdev->actconfig || !hdev->maxchild)
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		return NULL;
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	return usb_get_intfdata(hdev->actconfig->interface[0]);
}

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static int usb_device_supports_lpm(struct usb_device *udev)
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{
	/* USB 2.1 (and greater) devices indicate LPM support through
	 * their USB 2.0 Extended Capabilities BOS descriptor.
	 */
	if (udev->speed == USB_SPEED_HIGH) {
		if (udev->bos->ext_cap &&
			(USB_LPM_SUPPORT &
			 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
			return 1;
		return 0;
	}
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	/*
	 * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
	 * However, there are some that don't, and they set the U1/U2 exit
	 * latencies to zero.
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	 */
	if (!udev->bos->ss_cap) {
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		dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
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		return 0;
	}

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	if (udev->bos->ss_cap->bU1devExitLat == 0 &&
			udev->bos->ss_cap->bU2DevExitLat == 0) {
		if (udev->parent)
			dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
		else
			dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
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		return 0;
	}

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	if (!udev->parent || udev->parent->lpm_capable)
		return 1;
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	return 0;
}

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/*
 * Set the Maximum Exit Latency (MEL) for the host to initiate a transition from
 * either U1 or U2.
 */
static void usb_set_lpm_mel(struct usb_device *udev,
		struct usb3_lpm_parameters *udev_lpm_params,
		unsigned int udev_exit_latency,
		struct usb_hub *hub,
		struct usb3_lpm_parameters *hub_lpm_params,
		unsigned int hub_exit_latency)
{
	unsigned int total_mel;
	unsigned int device_mel;
	unsigned int hub_mel;

	/*
	 * Calculate the time it takes to transition all links from the roothub
	 * to the parent hub into U0.  The parent hub must then decode the
	 * packet (hub header decode latency) to figure out which port it was
	 * bound for.
	 *
	 * The Hub Header decode latency is expressed in 0.1us intervals (0x1
	 * means 0.1us).  Multiply that by 100 to get nanoseconds.
	 */
	total_mel = hub_lpm_params->mel +
		(hub->descriptor->u.ss.bHubHdrDecLat * 100);

	/*
	 * How long will it take to transition the downstream hub's port into
	 * U0?  The greater of either the hub exit latency or the device exit
	 * latency.
	 *
	 * The BOS U1/U2 exit latencies are expressed in 1us intervals.
	 * Multiply that by 1000 to get nanoseconds.
	 */
	device_mel = udev_exit_latency * 1000;
	hub_mel = hub_exit_latency * 1000;
	if (device_mel > hub_mel)
		total_mel += device_mel;
	else
		total_mel += hub_mel;

	udev_lpm_params->mel = total_mel;
}

/*
 * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
 * a transition from either U1 or U2.
 */
static void usb_set_lpm_pel(struct usb_device *udev,
		struct usb3_lpm_parameters *udev_lpm_params,
		unsigned int udev_exit_latency,
		struct usb_hub *hub,
		struct usb3_lpm_parameters *hub_lpm_params,
		unsigned int hub_exit_latency,
		unsigned int port_to_port_exit_latency)
{
	unsigned int first_link_pel;
	unsigned int hub_pel;

	/*
	 * First, the device sends an LFPS to transition the link between the
	 * device and the parent hub into U0.  The exit latency is the bigger of
	 * the device exit latency or the hub exit latency.
	 */
	if (udev_exit_latency > hub_exit_latency)
		first_link_pel = udev_exit_latency * 1000;
	else
		first_link_pel = hub_exit_latency * 1000;

	/*
	 * When the hub starts to receive the LFPS, there is a slight delay for
	 * it to figure out that one of the ports is sending an LFPS.  Then it
	 * will forward the LFPS to its upstream link.  The exit latency is the
	 * delay, plus the PEL that we calculated for this hub.
	 */
	hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;

	/*
	 * According to figure C-7 in the USB 3.0 spec, the PEL for this device
	 * is the greater of the two exit latencies.
	 */
	if (first_link_pel > hub_pel)
		udev_lpm_params->pel = first_link_pel;
	else
		udev_lpm_params->pel = hub_pel;
}

/*
 * Set the System Exit Latency (SEL) to indicate the total worst-case time from
 * when a device initiates a transition to U0, until when it will receive the
 * first packet from the host controller.
 *
 * Section C.1.5.1 describes the four components to this:
 *  - t1: device PEL
 *  - t2: time for the ERDY to make it from the device to the host.
 *  - t3: a host-specific delay to process the ERDY.
 *  - t4: time for the packet to make it from the host to the device.
 *
 * t3 is specific to both the xHCI host and the platform the host is integrated
 * into.  The Intel HW folks have said it's negligible, FIXME if a different
 * vendor says otherwise.
 */
static void usb_set_lpm_sel(struct usb_device *udev,
		struct usb3_lpm_parameters *udev_lpm_params)
{
	struct usb_device *parent;
	unsigned int num_hubs;
	unsigned int total_sel;

	/* t1 = device PEL */
	total_sel = udev_lpm_params->pel;
	/* How many external hubs are in between the device & the root port. */
	for (parent = udev->parent, num_hubs = 0; parent->parent;
			parent = parent->parent)
		num_hubs++;
	/* t2 = 2.1us + 250ns * (num_hubs - 1) */
	if (num_hubs > 0)
		total_sel += 2100 + 250 * (num_hubs - 1);

	/* t4 = 250ns * num_hubs */
	total_sel += 250 * num_hubs;

	udev_lpm_params->sel = total_sel;
}

static void usb_set_lpm_parameters(struct usb_device *udev)
{
	struct usb_hub *hub;
	unsigned int port_to_port_delay;
	unsigned int udev_u1_del;
	unsigned int udev_u2_del;
	unsigned int hub_u1_del;
	unsigned int hub_u2_del;

	if (!udev->lpm_capable || udev->speed != USB_SPEED_SUPER)
		return;

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	hub = usb_hub_to_struct_hub(udev->parent);
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	/* It doesn't take time to transition the roothub into U0, since it
	 * doesn't have an upstream link.
	 */
	if (!hub)
		return;

	udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
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	udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
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	hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
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	hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
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	usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
			hub, &udev->parent->u1_params, hub_u1_del);

	usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
			hub, &udev->parent->u2_params, hub_u2_del);

	/*
	 * Appendix C, section C.2.2.2, says that there is a slight delay from
	 * when the parent hub notices the downstream port is trying to
	 * transition to U0 to when the hub initiates a U0 transition on its
	 * upstream port.  The section says the delays are tPort2PortU1EL and
	 * tPort2PortU2EL, but it doesn't define what they are.
	 *
	 * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
	 * about the same delays.  Use the maximum delay calculations from those
	 * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
	 * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
	 * assume the device exit latencies they are talking about are the hub
	 * exit latencies.
	 *
	 * What do we do if the U2 exit latency is less than the U1 exit
	 * latency?  It's possible, although not likely...
	 */
	port_to_port_delay = 1;

	usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
			hub, &udev->parent->u1_params, hub_u1_del,
			port_to_port_delay);

	if (hub_u2_del > hub_u1_del)
		port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
	else
		port_to_port_delay = 1 + hub_u1_del;

	usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
			hub, &udev->parent->u2_params, hub_u2_del,
			port_to_port_delay);

	/* Now that we've got PEL, calculate SEL. */
	usb_set_lpm_sel(udev, &udev->u1_params);
	usb_set_lpm_sel(udev, &udev->u2_params);
}

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/* USB 2.0 spec Section 11.24.4.5 */
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static int get_hub_descriptor(struct usb_device *hdev, void *data)
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{
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	int i, ret, size;
	unsigned dtype;

	if (hub_is_superspeed(hdev)) {
		dtype = USB_DT_SS_HUB;
		size = USB_DT_SS_HUB_SIZE;
	} else {
		dtype = USB_DT_HUB;
		size = sizeof(struct usb_hub_descriptor);
	}
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	for (i = 0; i < 3; i++) {
		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
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			dtype << 8, 0, data, size,
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			USB_CTRL_GET_TIMEOUT);
		if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
			return ret;
	}
	return -EINVAL;
}

/*
 * USB 2.0 spec Section 11.24.2.1
 */
static int clear_hub_feature(struct usb_device *hdev, int feature)
{
	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
}

/*
 * USB 2.0 spec Section 11.24.2.2
 */
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int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
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{
	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
		NULL, 0, 1000);
}

/*
 * USB 2.0 spec Section 11.24.2.13
 */
static int set_port_feature(struct usb_device *hdev, int port1, int feature)
{
	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
		NULL, 0, 1000);
}

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static char *to_led_name(int selector)
{
	switch (selector) {
	case HUB_LED_AMBER:
		return "amber";
	case HUB_LED_GREEN:
		return "green";
	case HUB_LED_OFF:
		return "off";
	case HUB_LED_AUTO:
		return "auto";
	default:
		return "??";
	}
}

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/*
 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 * for info about using port indicators
 */
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static void set_port_led(struct usb_hub *hub, int port1, int selector)
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{
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	struct usb_port *port_dev = hub->ports[port1 - 1];
	int status;

	status = set_port_feature(hub->hdev, (selector << 8) | port1,
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			USB_PORT_FEAT_INDICATOR);
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	dev_dbg(&port_dev->dev, "indicator %s status %d\n",
		to_led_name(selector), status);
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}

#define	LED_CYCLE_PERIOD	((2*HZ)/3)

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static void led_work (struct work_struct *work)
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{
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	struct usb_hub		*hub =
		container_of(work, struct usb_hub, leds.work);
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	struct usb_device	*hdev = hub->hdev;
	unsigned		i;
	unsigned		changed = 0;
	int			cursor = -1;

	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
		return;

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	for (i = 0; i < hdev->maxchild; i++) {
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		unsigned	selector, mode;

		/* 30%-50% duty cycle */

		switch (hub->indicator[i]) {
		/* cycle marker */
		case INDICATOR_CYCLE:
			cursor = i;
			selector = HUB_LED_AUTO;
			mode = INDICATOR_AUTO;
			break;
		/* blinking green = sw attention */
		case INDICATOR_GREEN_BLINK:
			selector = HUB_LED_GREEN;
			mode = INDICATOR_GREEN_BLINK_OFF;
			break;
		case INDICATOR_GREEN_BLINK_OFF:
			selector = HUB_LED_OFF;
			mode = INDICATOR_GREEN_BLINK;
			break;
		/* blinking amber = hw attention */
		case INDICATOR_AMBER_BLINK:
			selector = HUB_LED_AMBER;
			mode = INDICATOR_AMBER_BLINK_OFF;
			break;
		case INDICATOR_AMBER_BLINK_OFF:
			selector = HUB_LED_OFF;
			mode = INDICATOR_AMBER_BLINK;
			break;
		/* blink green/amber = reserved */
		case INDICATOR_ALT_BLINK:
			selector = HUB_LED_GREEN;
			mode = INDICATOR_ALT_BLINK_OFF;
			break;
		case INDICATOR_ALT_BLINK_OFF:
			selector = HUB_LED_AMBER;
			mode = INDICATOR_ALT_BLINK;
			break;
		default:
			continue;
		}
		if (selector != HUB_LED_AUTO)
			changed = 1;
		set_port_led(hub, i + 1, selector);
		hub->indicator[i] = mode;
	}
	if (!changed && blinkenlights) {
		cursor++;
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		cursor %= hdev->maxchild;
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		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
		hub->indicator[cursor] = INDICATOR_CYCLE;
		changed++;
	}
	if (changed)
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		queue_delayed_work(system_power_efficient_wq,
				&hub->leds, LED_CYCLE_PERIOD);
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}

/* use a short timeout for hub/port status fetches */
#define	USB_STS_TIMEOUT		1000
#define	USB_STS_RETRIES		5

/*
 * USB 2.0 spec Section 11.24.2.6
 */
static int get_hub_status(struct usb_device *hdev,
		struct usb_hub_status *data)
{
	int i, status = -ETIMEDOUT;

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	for (i = 0; i < USB_STS_RETRIES &&
			(status == -ETIMEDOUT || status == -EPIPE); i++) {
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		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
			data, sizeof(*data), USB_STS_TIMEOUT);
	}
	return status;
}

/*
 * USB 2.0 spec Section 11.24.2.7
 */
static int get_port_status(struct usb_device *hdev, int port1,
		struct usb_port_status *data)
{
	int i, status = -ETIMEDOUT;

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	for (i = 0; i < USB_STS_RETRIES &&
			(status == -ETIMEDOUT || status == -EPIPE); i++) {
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		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
			data, sizeof(*data), USB_STS_TIMEOUT);
	}
	return status;
}

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static int hub_port_status(struct usb_hub *hub, int port1,
		u16 *status, u16 *change)
{
	int ret;

	mutex_lock(&hub->status_mutex);
	ret = get_port_status(hub->hdev, port1, &hub->status->port);
	if (ret < 4) {
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		if (ret != -ENODEV)
			dev_err(hub->intfdev,
				"%s failed (err = %d)\n", __func__, ret);
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		if (ret >= 0)
			ret = -EIO;
	} else {
		*status = le16_to_cpu(hub->status->port.wPortStatus);
		*change = le16_to_cpu(hub->status->port.wPortChange);
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		ret = 0;
	}
	mutex_unlock(&hub->status_mutex);
	return ret;
}

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static void kick_khubd(struct usb_hub *hub)
{
	unsigned long	flags;

	spin_lock_irqsave(&hub_event_lock, flags);
584
	if (!hub->disconnected && list_empty(&hub->event_list)) {
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		list_add_tail(&hub->event_list, &hub_event_list);
586 587 588 589

		/* Suppress autosuspend until khubd runs */
		usb_autopm_get_interface_no_resume(
				to_usb_interface(hub->intfdev));
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		wake_up(&khubd_wait);
	}
	spin_unlock_irqrestore(&hub_event_lock, flags);
}

void usb_kick_khubd(struct usb_device *hdev)
{
597
	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
598 599 600

	if (hub)
		kick_khubd(hub);
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}

603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618
/*
 * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
 * Notification, which indicates it had initiated remote wakeup.
 *
 * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
 * device initiates resume, so the USB core will not receive notice of the
 * resume through the normal hub interrupt URB.
 */
void usb_wakeup_notification(struct usb_device *hdev,
		unsigned int portnum)
{
	struct usb_hub *hub;

	if (!hdev)
		return;

619
	hub = usb_hub_to_struct_hub(hdev);
620 621 622 623 624 625
	if (hub) {
		set_bit(portnum, hub->wakeup_bits);
		kick_khubd(hub);
	}
}
EXPORT_SYMBOL_GPL(usb_wakeup_notification);
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/* completion function, fires on port status changes and various faults */
628
static void hub_irq(struct urb *urb)
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629
{
630
	struct usb_hub *hub = urb->context;
631
	int status = urb->status;
632
	unsigned i;
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633 634
	unsigned long bits;

635
	switch (status) {
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	case -ENOENT:		/* synchronous unlink */
	case -ECONNRESET:	/* async unlink */
	case -ESHUTDOWN:	/* hardware going away */
		return;

	default:		/* presumably an error */
		/* Cause a hub reset after 10 consecutive errors */
643
		dev_dbg (hub->intfdev, "transfer --> %d\n", status);
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		if ((++hub->nerrors < 10) || hub->error)
			goto resubmit;
646
		hub->error = status;
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		/* FALL THROUGH */
648

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	/* let khubd handle things */
	case 0:			/* we got data:  port status changed */
		bits = 0;
		for (i = 0; i < urb->actual_length; ++i)
			bits |= ((unsigned long) ((*hub->buffer)[i]))
					<< (i*8);
		hub->event_bits[0] = bits;
		break;
	}

	hub->nerrors = 0;

	/* Something happened, let khubd figure it out */
	kick_khubd(hub);

resubmit:
	if (hub->quiescing)
		return;

	if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
			&& status != -ENODEV && status != -EPERM)
		dev_err (hub->intfdev, "resubmit --> %d\n", status);
}

/* USB 2.0 spec Section 11.24.2.3 */
static inline int
hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
{
677 678 679 680 681 682 683 684 685
	/* Need to clear both directions for control ep */
	if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
			USB_ENDPOINT_XFER_CONTROL) {
		int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
				HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
				devinfo ^ 0x8000, tt, NULL, 0, 1000);
		if (status)
			return status;
	}
686
	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
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			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
			       tt, NULL, 0, 1000);
}

/*
 * enumeration blocks khubd for a long time. we use keventd instead, since
 * long blocking there is the exception, not the rule.  accordingly, HCDs
 * talking to TTs must queue control transfers (not just bulk and iso), so
 * both can talk to the same hub concurrently.
 */
697
static void hub_tt_work(struct work_struct *work)
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{
D
David Howells 已提交
699
	struct usb_hub		*hub =
700
		container_of(work, struct usb_hub, tt.clear_work);
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	unsigned long		flags;

	spin_lock_irqsave (&hub->tt.lock, flags);
704
	while (!list_empty(&hub->tt.clear_list)) {
705
		struct list_head	*next;
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		struct usb_tt_clear	*clear;
		struct usb_device	*hdev = hub->hdev;
708
		const struct hc_driver	*drv;
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		int			status;

711 712
		next = hub->tt.clear_list.next;
		clear = list_entry (next, struct usb_tt_clear, clear_list);
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		list_del (&clear->clear_list);

		/* drop lock so HCD can concurrently report other TT errors */
		spin_unlock_irqrestore (&hub->tt.lock, flags);
		status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
718
		if (status && status != -ENODEV)
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719 720 721
			dev_err (&hdev->dev,
				"clear tt %d (%04x) error %d\n",
				clear->tt, clear->devinfo, status);
722 723 724 725 726 727

		/* Tell the HCD, even if the operation failed */
		drv = clear->hcd->driver;
		if (drv->clear_tt_buffer_complete)
			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);

728
		kfree(clear);
729
		spin_lock_irqsave(&hub->tt.lock, flags);
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730 731 732 733
	}
	spin_unlock_irqrestore (&hub->tt.lock, flags);
}

734 735
/**
 * usb_hub_set_port_power - control hub port's power state
736 737
 * @hdev: USB device belonging to the usb hub
 * @hub: target hub
738 739 740 741 742
 * @port1: port index
 * @set: expected status
 *
 * call this function to control port's power via setting or
 * clearing the port's PORT_POWER feature.
743 744
 *
 * Return: 0 if successful. A negative error code otherwise.
745
 */
746 747
int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
			   int port1, bool set)
748 749 750 751 752 753
{
	int ret;

	if (set)
		ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
	else
754 755
		ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);

756 757 758 759 760 761 762 763
	if (ret)
		return ret;

	if (set)
		set_bit(port1, hub->power_bits);
	else
		clear_bit(port1, hub->power_bits);
	return 0;
764 765
}

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/**
767 768
 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 * @urb: an URB associated with the failed or incomplete split transaction
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 *
 * High speed HCDs use this to tell the hub driver that some split control or
 * bulk transaction failed in a way that requires clearing internal state of
 * a transaction translator.  This is normally detected (and reported) from
 * interrupt context.
 *
 * It may not be possible for that hub to handle additional full (or low)
 * speed transactions until that state is fully cleared out.
777 778
 *
 * Return: 0 if successful. A negative error code otherwise.
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 */
780
int usb_hub_clear_tt_buffer(struct urb *urb)
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781
{
782 783
	struct usb_device	*udev = urb->dev;
	int			pipe = urb->pipe;
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	struct usb_tt		*tt = udev->tt;
	unsigned long		flags;
	struct usb_tt_clear	*clear;

	/* we've got to cope with an arbitrary number of pending TT clears,
	 * since each TT has "at least two" buffers that can need it (and
	 * there can be many TTs per hub).  even if they're uncommon.
	 */
792
	if ((clear = kmalloc (sizeof *clear, GFP_ATOMIC)) == NULL) {
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		dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
		/* FIXME recover somehow ... RESET_TT? */
795
		return -ENOMEM;
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	}

	/* info that CLEAR_TT_BUFFER needs */
	clear->tt = tt->multi ? udev->ttport : 1;
	clear->devinfo = usb_pipeendpoint (pipe);
	clear->devinfo |= udev->devnum << 4;
	clear->devinfo |= usb_pipecontrol (pipe)
			? (USB_ENDPOINT_XFER_CONTROL << 11)
			: (USB_ENDPOINT_XFER_BULK << 11);
	if (usb_pipein (pipe))
		clear->devinfo |= 1 << 15;
807 808 809 810 811

	/* info for completion callback */
	clear->hcd = bus_to_hcd(udev->bus);
	clear->ep = urb->ep;

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	/* tell keventd to clear state for this TT */
	spin_lock_irqsave (&tt->lock, flags);
	list_add_tail (&clear->clear_list, &tt->clear_list);
815
	schedule_work(&tt->clear_work);
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816
	spin_unlock_irqrestore (&tt->lock, flags);
817
	return 0;
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818
}
819
EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
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820

821
static void hub_power_on(struct usb_hub *hub, bool do_delay)
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822 823
{
	int port1;
824 825 826 827 828 829 830

	/* Enable power on each port.  Some hubs have reserved values
	 * of LPSM (> 2) in their descriptors, even though they are
	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
	 * but only emulate it.  In all cases, the ports won't work
	 * unless we send these messages to the hub.
	 */
831
	if (hub_is_port_power_switchable(hub))
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		dev_dbg(hub->intfdev, "enabling power on all ports\n");
833 834 835
	else
		dev_dbg(hub->intfdev, "trying to enable port power on "
				"non-switchable hub\n");
836
	for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
837
		if (test_bit(port1, hub->power_bits))
838 839 840 841
			set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
		else
			usb_clear_port_feature(hub->hdev, port1,
						USB_PORT_FEAT_POWER);
842
	if (do_delay)
843
		msleep(hub_power_on_good_delay(hub));
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}

static int hub_hub_status(struct usb_hub *hub,
		u16 *status, u16 *change)
{
	int ret;

851
	mutex_lock(&hub->status_mutex);
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852
	ret = get_hub_status(hub->hdev, &hub->status->hub);
853 854 855 856 857
	if (ret < 0) {
		if (ret != -ENODEV)
			dev_err(hub->intfdev,
				"%s failed (err = %d)\n", __func__, ret);
	} else {
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858
		*status = le16_to_cpu(hub->status->hub.wHubStatus);
859
		*change = le16_to_cpu(hub->status->hub.wHubChange);
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		ret = 0;
	}
862
	mutex_unlock(&hub->status_mutex);
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	return ret;
}

866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892
static int hub_set_port_link_state(struct usb_hub *hub, int port1,
			unsigned int link_status)
{
	return set_port_feature(hub->hdev,
			port1 | (link_status << 3),
			USB_PORT_FEAT_LINK_STATE);
}

/*
 * If USB 3.0 ports are placed into the Disabled state, they will no longer
 * detect any device connects or disconnects.  This is generally not what the
 * USB core wants, since it expects a disabled port to produce a port status
 * change event when a new device connects.
 *
 * Instead, set the link state to Disabled, wait for the link to settle into
 * that state, clear any change bits, and then put the port into the RxDetect
 * state.
 */
static int hub_usb3_port_disable(struct usb_hub *hub, int port1)
{
	int ret;
	int total_time;
	u16 portchange, portstatus;

	if (!hub_is_superspeed(hub->hdev))
		return -EINVAL;

893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911
	ret = hub_port_status(hub, port1, &portstatus, &portchange);
	if (ret < 0)
		return ret;

	/*
	 * USB controller Advanced Micro Devices, Inc. [AMD] FCH USB XHCI
	 * Controller [1022:7814] will have spurious result making the following
	 * usb 3.0 device hotplugging route to the 2.0 root hub and recognized
	 * as high-speed device if we set the usb 3.0 port link state to
	 * Disabled. Since it's already in USB_SS_PORT_LS_RX_DETECT state, we
	 * check the state here to avoid the bug.
	 */
	if ((portstatus & USB_PORT_STAT_LINK_STATE) ==
				USB_SS_PORT_LS_RX_DETECT) {
		dev_dbg(&hub->ports[port1 - 1]->dev,
			 "Not disabling port; link state is RxDetect\n");
		return ret;
	}

912
	ret = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_SS_DISABLED);
913
	if (ret)
914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929
		return ret;

	/* Wait for the link to enter the disabled state. */
	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
		ret = hub_port_status(hub, port1, &portstatus, &portchange);
		if (ret < 0)
			return ret;

		if ((portstatus & USB_PORT_STAT_LINK_STATE) ==
				USB_SS_PORT_LS_SS_DISABLED)
			break;
		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
			break;
		msleep(HUB_DEBOUNCE_STEP);
	}
	if (total_time >= HUB_DEBOUNCE_TIMEOUT)
930 931
		dev_warn(&hub->ports[port1 - 1]->dev,
				"Could not disable after %d ms\n", total_time);
932 933 934 935

	return hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_RX_DETECT);
}

936 937
static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
{
938
	struct usb_port *port_dev = hub->ports[port1 - 1];
939
	struct usb_device *hdev = hub->hdev;
A
Alan Stern 已提交
940
	int ret = 0;
941

942 943
	if (port_dev->child && set_state)
		usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
944 945 946 947
	if (!hub->error) {
		if (hub_is_superspeed(hub->hdev))
			ret = hub_usb3_port_disable(hub, port1);
		else
948
			ret = usb_clear_port_feature(hdev, port1,
949 950
					USB_PORT_FEAT_ENABLE);
	}
951
	if (ret && ret != -ENODEV)
952
		dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
953 954 955
	return ret;
}

A
Alan Stern 已提交
956
/*
957
 * Disable a port and mark a logical connect-change event, so that some
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Alan Stern 已提交
958 959 960 961 962
 * time later khubd will disconnect() any existing usb_device on the port
 * and will re-enumerate if there actually is a device attached.
 */
static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
{
963
	dev_dbg(&hub->ports[port1 - 1]->dev, "logical disconnect\n");
A
Alan Stern 已提交
964
	hub_port_disable(hub, port1, 1);
965

A
Alan Stern 已提交
966 967 968 969 970 971 972 973 974 975
	/* FIXME let caller ask to power down the port:
	 *  - some devices won't enumerate without a VBUS power cycle
	 *  - SRP saves power that way
	 *  - ... new call, TBD ...
	 * That's easy if this hub can switch power per-port, and
	 * khubd reactivates the port later (timer, SRP, etc).
	 * Powerdown must be optional, because of reset/DFU.
	 */

	set_bit(port1, hub->change_bits);
976
	kick_khubd(hub);
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Alan Stern 已提交
977 978
}

979 980 981 982 983 984 985 986 987
/**
 * usb_remove_device - disable a device's port on its parent hub
 * @udev: device to be disabled and removed
 * Context: @udev locked, must be able to sleep.
 *
 * After @udev's port has been disabled, khubd is notified and it will
 * see that the device has been disconnected.  When the device is
 * physically unplugged and something is plugged in, the events will
 * be received and processed normally.
988 989
 *
 * Return: 0 if successful. A negative error code otherwise.
990 991 992 993 994 995 996 997
 */
int usb_remove_device(struct usb_device *udev)
{
	struct usb_hub *hub;
	struct usb_interface *intf;

	if (!udev->parent)	/* Can't remove a root hub */
		return -EINVAL;
998
	hub = usb_hub_to_struct_hub(udev->parent);
999 1000 1001 1002 1003 1004 1005 1006 1007
	intf = to_usb_interface(hub->intfdev);

	usb_autopm_get_interface(intf);
	set_bit(udev->portnum, hub->removed_bits);
	hub_port_logical_disconnect(hub, udev->portnum);
	usb_autopm_put_interface(intf);
	return 0;
}

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Alan Stern 已提交
1008
enum hub_activation_type {
1009
	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
1010
	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
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Alan Stern 已提交
1011
};
1012

1013 1014 1015
static void hub_init_func2(struct work_struct *ws);
static void hub_init_func3(struct work_struct *ws);

1016
static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
1017 1018
{
	struct usb_device *hdev = hub->hdev;
1019 1020
	struct usb_hcd *hcd;
	int ret;
1021
	int port1;
1022
	int status;
1023
	bool need_debounce_delay = false;
1024 1025 1026 1027 1028 1029 1030
	unsigned delay;

	/* Continue a partial initialization */
	if (type == HUB_INIT2)
		goto init2;
	if (type == HUB_INIT3)
		goto init3;
1031

1032 1033 1034 1035 1036 1037 1038 1039
	/* The superspeed hub except for root hub has to use Hub Depth
	 * value as an offset into the route string to locate the bits
	 * it uses to determine the downstream port number. So hub driver
	 * should send a set hub depth request to superspeed hub after
	 * the superspeed hub is set configuration in initialization or
	 * reset procedure.
	 *
	 * After a resume, port power should still be on.
1040 1041
	 * For any other type of activation, turn it on.
	 */
1042
	if (type != HUB_RESUME) {
1043 1044 1045 1046 1047 1048 1049 1050 1051
		if (hdev->parent && hub_is_superspeed(hdev)) {
			ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
					HUB_SET_DEPTH, USB_RT_HUB,
					hdev->level - 1, 0, NULL, 0,
					USB_CTRL_SET_TIMEOUT);
			if (ret < 0)
				dev_err(hub->intfdev,
						"set hub depth failed\n");
		}
1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065

		/* Speed up system boot by using a delayed_work for the
		 * hub's initial power-up delays.  This is pretty awkward
		 * and the implementation looks like a home-brewed sort of
		 * setjmp/longjmp, but it saves at least 100 ms for each
		 * root hub (assuming usbcore is compiled into the kernel
		 * rather than as a module).  It adds up.
		 *
		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
		 * because for those activation types the ports have to be
		 * operational when we return.  In theory this could be done
		 * for HUB_POST_RESET, but it's easier not to.
		 */
		if (type == HUB_INIT) {
1066 1067 1068
			unsigned delay = hub_power_on_good_delay(hub);

			hub_power_on(hub, false);
T
Tejun Heo 已提交
1069
			INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
1070 1071
			queue_delayed_work(system_power_efficient_wq,
					&hub->init_work,
1072
					msecs_to_jiffies(delay));
1073 1074

			/* Suppress autosuspend until init is done */
1075 1076
			usb_autopm_get_interface_no_resume(
					to_usb_interface(hub->intfdev));
1077
			return;		/* Continues at init2: below */
1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096
		} else if (type == HUB_RESET_RESUME) {
			/* The internal host controller state for the hub device
			 * may be gone after a host power loss on system resume.
			 * Update the device's info so the HW knows it's a hub.
			 */
			hcd = bus_to_hcd(hdev->bus);
			if (hcd->driver->update_hub_device) {
				ret = hcd->driver->update_hub_device(hcd, hdev,
						&hub->tt, GFP_NOIO);
				if (ret < 0) {
					dev_err(hub->intfdev, "Host not "
							"accepting hub info "
							"update.\n");
					dev_err(hub->intfdev, "LS/FS devices "
							"and hubs may not work "
							"under this hub\n.");
				}
			}
			hub_power_on(hub, true);
1097 1098 1099 1100 1101
		} else {
			hub_power_on(hub, true);
		}
	}
 init2:
1102

1103 1104
	/*
	 * Check each port and set hub->change_bits to let khubd know
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Alan Stern 已提交
1105
	 * which ports need attention.
1106 1107
	 */
	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1108 1109
		struct usb_port *port_dev = hub->ports[port1 - 1];
		struct usb_device *udev = port_dev->child;
1110 1111
		u16 portstatus, portchange;

A
Alan Stern 已提交
1112 1113 1114
		portstatus = portchange = 0;
		status = hub_port_status(hub, port1, &portstatus, &portchange);
		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1115 1116
			dev_dbg(&port_dev->dev, "status %04x change %04x\n",
					portstatus, portchange);
A
Alan Stern 已提交
1117

1118 1119
		/*
		 * After anything other than HUB_RESUME (i.e., initialization
A
Alan Stern 已提交
1120 1121 1122 1123 1124 1125 1126 1127 1128
		 * or any sort of reset), every port should be disabled.
		 * Unconnected ports should likewise be disabled (paranoia),
		 * and so should ports for which we have no usb_device.
		 */
		if ((portstatus & USB_PORT_STAT_ENABLE) && (
				type != HUB_RESUME ||
				!(portstatus & USB_PORT_STAT_CONNECTION) ||
				!udev ||
				udev->state == USB_STATE_NOTATTACHED)) {
1129 1130 1131
			/*
			 * USB3 protocol ports will automatically transition
			 * to Enabled state when detect an USB3.0 device attach.
D
Dan Williams 已提交
1132 1133
			 * Do not disable USB3 protocol ports, just pretend
			 * power was lost
1134
			 */
D
Dan Williams 已提交
1135 1136
			portstatus &= ~USB_PORT_STAT_ENABLE;
			if (!hub_is_superspeed(hdev))
1137
				usb_clear_port_feature(hdev, port1,
1138
						   USB_PORT_FEAT_ENABLE);
1139 1140
		}

1141 1142 1143
		/* Clear status-change flags; we'll debounce later */
		if (portchange & USB_PORT_STAT_C_CONNECTION) {
			need_debounce_delay = true;
1144
			usb_clear_port_feature(hub->hdev, port1,
1145 1146 1147 1148
					USB_PORT_FEAT_C_CONNECTION);
		}
		if (portchange & USB_PORT_STAT_C_ENABLE) {
			need_debounce_delay = true;
1149
			usb_clear_port_feature(hub->hdev, port1,
1150 1151
					USB_PORT_FEAT_C_ENABLE);
		}
1152 1153 1154 1155 1156
		if (portchange & USB_PORT_STAT_C_RESET) {
			need_debounce_delay = true;
			usb_clear_port_feature(hub->hdev, port1,
					USB_PORT_FEAT_C_RESET);
		}
1157 1158 1159
		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
				hub_is_superspeed(hub->hdev)) {
			need_debounce_delay = true;
1160
			usb_clear_port_feature(hub->hdev, port1,
1161 1162
					USB_PORT_FEAT_C_BH_PORT_RESET);
		}
1163 1164 1165 1166 1167 1168 1169
		/* We can forget about a "removed" device when there's a
		 * physical disconnect or the connect status changes.
		 */
		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
				(portchange & USB_PORT_STAT_C_CONNECTION))
			clear_bit(port1, hub->removed_bits);

A
Alan Stern 已提交
1170 1171 1172 1173
		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
			/* Tell khubd to disconnect the device or
			 * check for a new connection
			 */
1174 1175
			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
			    (portstatus & USB_PORT_STAT_OVERCURRENT))
A
Alan Stern 已提交
1176 1177 1178
				set_bit(port1, hub->change_bits);

		} else if (portstatus & USB_PORT_STAT_ENABLE) {
1179 1180 1181
			bool port_resumed = (portstatus &
					USB_PORT_STAT_LINK_STATE) ==
				USB_SS_PORT_LS_U0;
A
Alan Stern 已提交
1182 1183 1184
			/* The power session apparently survived the resume.
			 * If there was an overcurrent or suspend change
			 * (i.e., remote wakeup request), have khubd
1185 1186 1187 1188
			 * take care of it.  Look at the port link state
			 * for USB 3.0 hubs, since they don't have a suspend
			 * change bit, and they don't set the port link change
			 * bit on device-initiated resume.
A
Alan Stern 已提交
1189
			 */
1190 1191
			if (portchange || (hub_is_superspeed(hub->hdev) &&
						port_resumed))
A
Alan Stern 已提交
1192
				set_bit(port1, hub->change_bits);
1193

A
Alan Stern 已提交
1194 1195
		} else if (udev->persist_enabled) {
#ifdef CONFIG_PM
1196
			udev->reset_resume = 1;
A
Alan Stern 已提交
1197
#endif
1198 1199 1200
			/* Don't set the change_bits when the device
			 * was powered off.
			 */
1201
			if (test_bit(port1, hub->power_bits))
1202
				set_bit(port1, hub->change_bits);
1203

A
Alan Stern 已提交
1204 1205 1206 1207
		} else {
			/* The power session is gone; tell khubd */
			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
			set_bit(port1, hub->change_bits);
1208 1209 1210
		}
	}

1211 1212 1213 1214 1215 1216 1217 1218
	/* If no port-status-change flags were set, we don't need any
	 * debouncing.  If flags were set we can try to debounce the
	 * ports all at once right now, instead of letting khubd do them
	 * one at a time later on.
	 *
	 * If any port-status changes do occur during this delay, khubd
	 * will see them later and handle them normally.
	 */
1219 1220 1221 1222 1223
	if (need_debounce_delay) {
		delay = HUB_DEBOUNCE_STABLE;

		/* Don't do a long sleep inside a workqueue routine */
		if (type == HUB_INIT2) {
T
Tejun Heo 已提交
1224
			INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
1225 1226
			queue_delayed_work(system_power_efficient_wq,
					&hub->init_work,
1227 1228 1229 1230 1231 1232 1233
					msecs_to_jiffies(delay));
			return;		/* Continues at init3: below */
		} else {
			msleep(delay);
		}
	}
 init3:
1234 1235 1236 1237 1238 1239
	hub->quiescing = 0;

	status = usb_submit_urb(hub->urb, GFP_NOIO);
	if (status < 0)
		dev_err(hub->intfdev, "activate --> %d\n", status);
	if (hub->has_indicators && blinkenlights)
1240 1241
		queue_delayed_work(system_power_efficient_wq,
				&hub->leds, LED_CYCLE_PERIOD);
1242 1243 1244

	/* Scan all ports that need attention */
	kick_khubd(hub);
1245 1246 1247 1248

	/* Allow autosuspend if it was suppressed */
	if (type <= HUB_INIT3)
		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1249 1250
}

1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265
/* Implement the continuations for the delays above */
static void hub_init_func2(struct work_struct *ws)
{
	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);

	hub_activate(hub, HUB_INIT2);
}

static void hub_init_func3(struct work_struct *ws)
{
	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);

	hub_activate(hub, HUB_INIT3);
}

1266 1267 1268 1269 1270 1271 1272 1273 1274
enum hub_quiescing_type {
	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
};

static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
{
	struct usb_device *hdev = hub->hdev;
	int i;

1275 1276
	cancel_delayed_work_sync(&hub->init_work);

1277 1278 1279 1280 1281 1282
	/* khubd and related activity won't re-trigger */
	hub->quiescing = 1;

	if (type != HUB_SUSPEND) {
		/* Disconnect all the children */
		for (i = 0; i < hdev->maxchild; ++i) {
1283 1284
			if (hub->ports[i]->child)
				usb_disconnect(&hub->ports[i]->child);
1285 1286 1287 1288 1289 1290 1291 1292
		}
	}

	/* Stop khubd and related activity */
	usb_kill_urb(hub->urb);
	if (hub->has_indicators)
		cancel_delayed_work_sync(&hub->leds);
	if (hub->tt.hub)
1293
		flush_work(&hub->tt.clear_work);
1294 1295
}

1296 1297 1298 1299 1300 1301 1302 1303
static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
{
	int i;

	for (i = 0; i < hub->hdev->maxchild; ++i)
		pm_runtime_barrier(&hub->ports[i]->dev);
}

A
Alan Stern 已提交
1304 1305 1306 1307 1308
/* caller has locked the hub device */
static int hub_pre_reset(struct usb_interface *intf)
{
	struct usb_hub *hub = usb_get_intfdata(intf);

1309
	hub_quiesce(hub, HUB_PRE_RESET);
1310 1311
	hub->in_reset = 1;
	hub_pm_barrier_for_all_ports(hub);
A
Alan Stern 已提交
1312
	return 0;
1313 1314 1315
}

/* caller has locked the hub device */
A
Alan Stern 已提交
1316
static int hub_post_reset(struct usb_interface *intf)
1317
{
1318 1319
	struct usb_hub *hub = usb_get_intfdata(intf);

1320 1321
	hub->in_reset = 0;
	hub_pm_barrier_for_all_ports(hub);
1322
	hub_activate(hub, HUB_POST_RESET);
A
Alan Stern 已提交
1323
	return 0;
1324 1325
}

L
Linus Torvalds 已提交
1326 1327 1328
static int hub_configure(struct usb_hub *hub,
	struct usb_endpoint_descriptor *endpoint)
{
1329
	struct usb_hcd *hcd;
L
Linus Torvalds 已提交
1330 1331 1332
	struct usb_device *hdev = hub->hdev;
	struct device *hub_dev = hub->intfdev;
	u16 hubstatus, hubchange;
1333
	u16 wHubCharacteristics;
L
Linus Torvalds 已提交
1334
	unsigned int pipe;
L
Lan Tianyu 已提交
1335
	int maxp, ret, i;
1336
	char *message = "out of memory";
1337 1338
	unsigned unit_load;
	unsigned full_load;
1339
	unsigned maxchild;
L
Linus Torvalds 已提交
1340

1341
	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
L
Linus Torvalds 已提交
1342 1343 1344 1345 1346 1347 1348 1349 1350 1351
	if (!hub->buffer) {
		ret = -ENOMEM;
		goto fail;
	}

	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
	if (!hub->status) {
		ret = -ENOMEM;
		goto fail;
	}
1352
	mutex_init(&hub->status_mutex);
L
Linus Torvalds 已提交
1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363

	hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
	if (!hub->descriptor) {
		ret = -ENOMEM;
		goto fail;
	}

	/* Request the entire hub descriptor.
	 * hub->descriptor can handle USB_MAXCHILDREN ports,
	 * but the hub can/will return fewer bytes here.
	 */
J
John Youn 已提交
1364
	ret = get_hub_descriptor(hdev, hub->descriptor);
L
Linus Torvalds 已提交
1365 1366 1367 1368 1369 1370 1371
	if (ret < 0) {
		message = "can't read hub descriptor";
		goto fail;
	} else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
		message = "hub has too many ports!";
		ret = -ENODEV;
		goto fail;
1372 1373 1374 1375
	} else if (hub->descriptor->bNbrPorts == 0) {
		message = "hub doesn't have any ports!";
		ret = -ENODEV;
		goto fail;
L
Linus Torvalds 已提交
1376 1377
	}

1378 1379 1380
	maxchild = hub->descriptor->bNbrPorts;
	dev_info(hub_dev, "%d port%s detected\n", maxchild,
			(maxchild == 1) ? "" : "s");
L
Linus Torvalds 已提交
1381

1382
	hub->ports = kzalloc(maxchild * sizeof(struct usb_port *), GFP_KERNEL);
1383
	if (!hub->ports) {
1384 1385 1386 1387
		ret = -ENOMEM;
		goto fail;
	}

1388
	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1389 1390 1391 1392 1393 1394 1395
	if (hub_is_superspeed(hdev)) {
		unit_load = 150;
		full_load = 900;
	} else {
		unit_load = 100;
		full_load = 500;
	}
L
Linus Torvalds 已提交
1396

J
John Youn 已提交
1397 1398 1399
	/* FIXME for USB 3.0, skip for now */
	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
			!(hub_is_superspeed(hdev))) {
L
Linus Torvalds 已提交
1400
		int	i;
1401
		char	portstr[USB_MAXCHILDREN + 1];
L
Linus Torvalds 已提交
1402

1403
		for (i = 0; i < maxchild; i++)
J
John Youn 已提交
1404
			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
L
Linus Torvalds 已提交
1405 1406
				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
				? 'F' : 'R';
1407
		portstr[maxchild] = 0;
L
Linus Torvalds 已提交
1408 1409 1410 1411
		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
	} else
		dev_dbg(hub_dev, "standalone hub\n");

1412
	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1413 1414 1415 1416 1417 1418 1419 1420 1421 1422
	case HUB_CHAR_COMMON_LPSM:
		dev_dbg(hub_dev, "ganged power switching\n");
		break;
	case HUB_CHAR_INDV_PORT_LPSM:
		dev_dbg(hub_dev, "individual port power switching\n");
		break;
	case HUB_CHAR_NO_LPSM:
	case HUB_CHAR_LPSM:
		dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
		break;
L
Linus Torvalds 已提交
1423 1424
	}

1425
	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1426 1427 1428 1429 1430 1431 1432 1433 1434 1435
	case HUB_CHAR_COMMON_OCPM:
		dev_dbg(hub_dev, "global over-current protection\n");
		break;
	case HUB_CHAR_INDV_PORT_OCPM:
		dev_dbg(hub_dev, "individual port over-current protection\n");
		break;
	case HUB_CHAR_NO_OCPM:
	case HUB_CHAR_OCPM:
		dev_dbg(hub_dev, "no over-current protection\n");
		break;
L
Linus Torvalds 已提交
1436 1437 1438 1439
	}

	spin_lock_init (&hub->tt.lock);
	INIT_LIST_HEAD (&hub->tt.clear_list);
1440
	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
L
Linus Torvalds 已提交
1441
	switch (hdev->descriptor.bDeviceProtocol) {
1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464
	case USB_HUB_PR_FS:
		break;
	case USB_HUB_PR_HS_SINGLE_TT:
		dev_dbg(hub_dev, "Single TT\n");
		hub->tt.hub = hdev;
		break;
	case USB_HUB_PR_HS_MULTI_TT:
		ret = usb_set_interface(hdev, 0, 1);
		if (ret == 0) {
			dev_dbg(hub_dev, "TT per port\n");
			hub->tt.multi = 1;
		} else
			dev_err(hub_dev, "Using single TT (err %d)\n",
				ret);
		hub->tt.hub = hdev;
		break;
	case USB_HUB_PR_SS:
		/* USB 3.0 hubs don't have a TT */
		break;
	default:
		dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
			hdev->descriptor.bDeviceProtocol);
		break;
L
Linus Torvalds 已提交
1465 1466
	}

1467
	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1468
	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1469 1470 1471
	case HUB_TTTT_8_BITS:
		if (hdev->descriptor.bDeviceProtocol != 0) {
			hub->tt.think_time = 666;
1472 1473
			dev_dbg(hub_dev, "TT requires at most %d "
					"FS bit times (%d ns)\n",
1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494
				8, hub->tt.think_time);
		}
		break;
	case HUB_TTTT_16_BITS:
		hub->tt.think_time = 666 * 2;
		dev_dbg(hub_dev, "TT requires at most %d "
				"FS bit times (%d ns)\n",
			16, hub->tt.think_time);
		break;
	case HUB_TTTT_24_BITS:
		hub->tt.think_time = 666 * 3;
		dev_dbg(hub_dev, "TT requires at most %d "
				"FS bit times (%d ns)\n",
			24, hub->tt.think_time);
		break;
	case HUB_TTTT_32_BITS:
		hub->tt.think_time = 666 * 4;
		dev_dbg(hub_dev, "TT requires at most %d "
				"FS bit times (%d ns)\n",
			32, hub->tt.think_time);
		break;
L
Linus Torvalds 已提交
1495 1496 1497
	}

	/* probe() zeroes hub->indicator[] */
1498
	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
L
Linus Torvalds 已提交
1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509
		hub->has_indicators = 1;
		dev_dbg(hub_dev, "Port indicators are supported\n");
	}

	dev_dbg(hub_dev, "power on to power good time: %dms\n",
		hub->descriptor->bPwrOn2PwrGood * 2);

	/* power budgeting mostly matters with bus-powered hubs,
	 * and battery-powered root hubs (may provide just 8 mA).
	 */
	ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1510
	if (ret) {
L
Linus Torvalds 已提交
1511 1512 1513
		message = "can't get hub status";
		goto fail;
	}
1514
	hcd = bus_to_hcd(hdev->bus);
1515
	if (hdev == hdev->bus->root_hub) {
1516 1517 1518
		if (hcd->power_budget > 0)
			hdev->bus_mA = hcd->power_budget;
		else
1519
			hdev->bus_mA = full_load * maxchild;
1520 1521
		if (hdev->bus_mA >= full_load)
			hub->mA_per_port = full_load;
1522 1523 1524 1525
		else {
			hub->mA_per_port = hdev->bus_mA;
			hub->limited_power = 1;
		}
1526
	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1527 1528 1529
		int remaining = hdev->bus_mA -
			hub->descriptor->bHubContrCurrent;

L
Linus Torvalds 已提交
1530 1531
		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
			hub->descriptor->bHubContrCurrent);
1532 1533
		hub->limited_power = 1;

1534
		if (remaining < maxchild * unit_load)
1535
			dev_warn(hub_dev,
1536 1537
					"insufficient power available "
					"to use all downstream ports\n");
1538 1539
		hub->mA_per_port = unit_load;	/* 7.2.1 */

1540 1541 1542
	} else {	/* Self-powered external hub */
		/* FIXME: What about battery-powered external hubs that
		 * provide less current per port? */
1543
		hub->mA_per_port = full_load;
1544
	}
1545
	if (hub->mA_per_port < full_load)
1546 1547
		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
				hub->mA_per_port);
L
Linus Torvalds 已提交
1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560

	ret = hub_hub_status(hub, &hubstatus, &hubchange);
	if (ret < 0) {
		message = "can't get hub status";
		goto fail;
	}

	/* local power status reports aren't always correct */
	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
		dev_dbg(hub_dev, "local power source is %s\n",
			(hubstatus & HUB_STATUS_LOCAL_POWER)
			? "lost (inactive)" : "good");

1561
	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
L
Linus Torvalds 已提交
1562 1563 1564
		dev_dbg(hub_dev, "%sover-current condition exists\n",
			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");

1565 1566 1567 1568 1569 1570
	/* set up the interrupt endpoint
	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
	 * bytes as USB2.0[11.12.3] says because some hubs are known
	 * to send more data (and thus cause overflow). For root hubs,
	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
	 * to be big enough for at least USB_MAXCHILDREN ports. */
L
Linus Torvalds 已提交
1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587
	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
	maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));

	if (maxp > sizeof(*hub->buffer))
		maxp = sizeof(*hub->buffer);

	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!hub->urb) {
		ret = -ENOMEM;
		goto fail;
	}

	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
		hub, endpoint->bInterval);

	/* maybe cycle the hub leds */
	if (hub->has_indicators && blinkenlights)
1588
		hub->indicator[0] = INDICATOR_CYCLE;
L
Linus Torvalds 已提交
1589

1590 1591
	mutex_lock(&usb_port_peer_mutex);
	for (i = 0; i < maxchild; i++) {
1592 1593
		ret = usb_hub_create_port_device(hub, i + 1);
		if (ret < 0) {
L
Lan Tianyu 已提交
1594 1595
			dev_err(hub->intfdev,
				"couldn't create port%d device.\n", i + 1);
1596
			break;
1597 1598
		}
	}
1599
	hdev->maxchild = i;
1600 1601 1602 1603 1604 1605
	for (i = 0; i < hdev->maxchild; i++) {
		struct usb_port *port_dev = hub->ports[i];

		pm_runtime_put(&port_dev->dev);
	}

1606 1607 1608
	mutex_unlock(&usb_port_peer_mutex);
	if (ret < 0)
		goto fail;
L
Lan Tianyu 已提交
1609

1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621
	/* Update the HCD's internal representation of this hub before khubd
	 * starts getting port status changes for devices under the hub.
	 */
	if (hcd->driver->update_hub_device) {
		ret = hcd->driver->update_hub_device(hcd, hdev,
				&hub->tt, GFP_KERNEL);
		if (ret < 0) {
			message = "can't update HCD hub info";
			goto fail;
		}
	}

1622 1623
	usb_hub_adjust_deviceremovable(hdev, hub->descriptor);

1624
	hub_activate(hub, HUB_INIT);
L
Linus Torvalds 已提交
1625 1626 1627 1628 1629 1630 1631 1632 1633
	return 0;

fail:
	dev_err (hub_dev, "config failed, %s (err %d)\n",
			message, ret);
	/* hub_disconnect() frees urb and descriptor */
	return ret;
}

1634 1635 1636 1637 1638 1639 1640 1641
static void hub_release(struct kref *kref)
{
	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);

	usb_put_intf(to_usb_interface(hub->intfdev));
	kfree(hub);
}

L
Linus Torvalds 已提交
1642 1643 1644 1645
static unsigned highspeed_hubs;

static void hub_disconnect(struct usb_interface *intf)
{
1646
	struct usb_hub *hub = usb_get_intfdata(intf);
1647
	struct usb_device *hdev = interface_to_usbdev(intf);
1648
	int port1;
L
Lan Tianyu 已提交
1649

1650 1651
	/* Take the hub off the event list and don't let it be added again */
	spin_lock_irq(&hub_event_lock);
1652 1653 1654 1655
	if (!list_empty(&hub->event_list)) {
		list_del_init(&hub->event_list);
		usb_autopm_put_interface_no_suspend(intf);
	}
1656 1657
	hub->disconnected = 1;
	spin_unlock_irq(&hub_event_lock);
L
Linus Torvalds 已提交
1658

1659 1660
	/* Disconnect all children and quiesce the hub */
	hub->error = 0;
1661
	hub_quiesce(hub, HUB_DISCONNECT);
1662

1663 1664
	mutex_lock(&usb_port_peer_mutex);

1665 1666 1667 1668 1669 1670
	/* Avoid races with recursively_mark_NOTATTACHED() */
	spin_lock_irq(&device_state_lock);
	port1 = hdev->maxchild;
	hdev->maxchild = 0;
	usb_set_intfdata(intf, NULL);
	spin_unlock_irq(&device_state_lock);
1671

1672 1673
	for (; port1 > 0; --port1)
		usb_hub_remove_port_device(hub, port1);
L
Linus Torvalds 已提交
1674

1675 1676
	mutex_unlock(&usb_port_peer_mutex);

1677
	if (hub->hdev->speed == USB_SPEED_HIGH)
L
Linus Torvalds 已提交
1678 1679 1680
		highspeed_hubs--;

	usb_free_urb(hub->urb);
L
Lan Tianyu 已提交
1681
	kfree(hub->ports);
1682 1683
	kfree(hub->descriptor);
	kfree(hub->status);
1684
	kfree(hub->buffer);
L
Linus Torvalds 已提交
1685

1686
	pm_suspend_ignore_children(&intf->dev, false);
1687
	kref_put(&hub->kref, hub_release);
L
Linus Torvalds 已提交
1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699
}

static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
	struct usb_host_interface *desc;
	struct usb_endpoint_descriptor *endpoint;
	struct usb_device *hdev;
	struct usb_hub *hub;

	desc = intf->cur_altsetting;
	hdev = interface_to_usbdev(intf);

1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731
	/*
	 * Set default autosuspend delay as 0 to speedup bus suspend,
	 * based on the below considerations:
	 *
	 * - Unlike other drivers, the hub driver does not rely on the
	 *   autosuspend delay to provide enough time to handle a wakeup
	 *   event, and the submitted status URB is just to check future
	 *   change on hub downstream ports, so it is safe to do it.
	 *
	 * - The patch might cause one or more auto supend/resume for
	 *   below very rare devices when they are plugged into hub
	 *   first time:
	 *
	 *   	devices having trouble initializing, and disconnect
	 *   	themselves from the bus and then reconnect a second
	 *   	or so later
	 *
	 *   	devices just for downloading firmware, and disconnects
	 *   	themselves after completing it
	 *
	 *   For these quite rare devices, their drivers may change the
	 *   autosuspend delay of their parent hub in the probe() to one
	 *   appropriate value to avoid the subtle problem if someone
	 *   does care it.
	 *
	 * - The patch may cause one or more auto suspend/resume on
	 *   hub during running 'lsusb', but it is probably too
	 *   infrequent to worry about.
	 *
	 * - Change autosuspend delay of hub can avoid unnecessary auto
	 *   suspend timer for hub, also may decrease power consumption
	 *   of USB bus.
1732 1733 1734
	 *
	 * - If user has indicated to prevent autosuspend by passing
	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
1735
	 */
1736
#ifdef CONFIG_PM_RUNTIME
1737 1738
	if (hdev->dev.power.autosuspend_delay >= 0)
		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
1739
#endif
1740

1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753
	/*
	 * Hubs have proper suspend/resume support, except for root hubs
	 * where the controller driver doesn't have bus_suspend and
	 * bus_resume methods.
	 */
	if (hdev->parent) {		/* normal device */
		usb_enable_autosuspend(hdev);
	} else {			/* root hub */
		const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;

		if (drv->bus_suspend && drv->bus_resume)
			usb_enable_autosuspend(hdev);
	}
1754

1755
	if (hdev->level == MAX_TOPO_LEVEL) {
1756 1757
		dev_err(&intf->dev,
			"Unsupported bus topology: hub nested too deep\n");
1758 1759 1760
		return -E2BIG;
	}

1761 1762 1763 1764 1765 1766 1767
#ifdef	CONFIG_USB_OTG_BLACKLIST_HUB
	if (hdev->parent) {
		dev_warn(&intf->dev, "ignoring external hub\n");
		return -ENODEV;
	}
#endif

L
Linus Torvalds 已提交
1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782
	/* Some hubs have a subclass of 1, which AFAICT according to the */
	/*  specs is not defined, but it works */
	if ((desc->desc.bInterfaceSubClass != 0) &&
	    (desc->desc.bInterfaceSubClass != 1)) {
descriptor_error:
		dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
		return -EIO;
	}

	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
	if (desc->desc.bNumEndpoints != 1)
		goto descriptor_error;

	endpoint = &desc->endpoint[0].desc;

1783 1784
	/* If it's not an interrupt in endpoint, we'd better punt! */
	if (!usb_endpoint_is_int_in(endpoint))
L
Linus Torvalds 已提交
1785 1786 1787 1788 1789
		goto descriptor_error;

	/* We found a hub */
	dev_info (&intf->dev, "USB hub found\n");

1790
	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
L
Linus Torvalds 已提交
1791 1792 1793 1794 1795
	if (!hub) {
		dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
		return -ENOMEM;
	}

1796
	kref_init(&hub->kref);
L
Linus Torvalds 已提交
1797 1798 1799
	INIT_LIST_HEAD(&hub->event_list);
	hub->intfdev = &intf->dev;
	hub->hdev = hdev;
D
David Howells 已提交
1800
	INIT_DELAYED_WORK(&hub->leds, led_work);
1801
	INIT_DELAYED_WORK(&hub->init_work, NULL);
1802
	usb_get_intf(intf);
L
Linus Torvalds 已提交
1803 1804

	usb_set_intfdata (intf, hub);
1805
	intf->needs_remote_wakeup = 1;
1806
	pm_suspend_ignore_children(&intf->dev, true);
L
Linus Torvalds 已提交
1807 1808 1809 1810

	if (hdev->speed == USB_SPEED_HIGH)
		highspeed_hubs++;

1811 1812 1813
	if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
		hub->quirk_check_port_auto_suspend = 1;

L
Linus Torvalds 已提交
1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824
	if (hub_configure(hub, endpoint) >= 0)
		return 0;

	hub_disconnect (intf);
	return -ENODEV;
}

static int
hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
{
	struct usb_device *hdev = interface_to_usbdev (intf);
1825
	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
L
Linus Torvalds 已提交
1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838

	/* assert ifno == 0 (part of hub spec) */
	switch (code) {
	case USBDEVFS_HUB_PORTINFO: {
		struct usbdevfs_hub_portinfo *info = user_data;
		int i;

		spin_lock_irq(&device_state_lock);
		if (hdev->devnum <= 0)
			info->nports = 0;
		else {
			info->nports = hdev->maxchild;
			for (i = 0; i < info->nports; i++) {
1839
				if (hub->ports[i]->child == NULL)
L
Linus Torvalds 已提交
1840 1841 1842
					info->port[i] = 0;
				else
					info->port[i] =
1843
						hub->ports[i]->child->devnum;
L
Linus Torvalds 已提交
1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855
			}
		}
		spin_unlock_irq(&device_state_lock);

		return info->nports + 1;
		}

	default:
		return -ENOSYS;
	}
}

1856 1857 1858 1859 1860
/*
 * Allow user programs to claim ports on a hub.  When a device is attached
 * to one of these "claimed" ports, the program will "own" the device.
 */
static int find_port_owner(struct usb_device *hdev, unsigned port1,
1861
		struct usb_dev_state ***ppowner)
1862
{
1863 1864
	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);

1865 1866 1867 1868 1869
	if (hdev->state == USB_STATE_NOTATTACHED)
		return -ENODEV;
	if (port1 == 0 || port1 > hdev->maxchild)
		return -EINVAL;

1870
	/* Devices not managed by the hub driver
1871 1872
	 * will always have maxchild equal to 0.
	 */
1873
	*ppowner = &(hub->ports[port1 - 1]->port_owner);
1874 1875 1876 1877
	return 0;
}

/* In the following three functions, the caller must hold hdev's lock */
1878
int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
1879
		       struct usb_dev_state *owner)
1880 1881
{
	int rc;
1882
	struct usb_dev_state **powner;
1883 1884 1885 1886 1887 1888 1889 1890 1891

	rc = find_port_owner(hdev, port1, &powner);
	if (rc)
		return rc;
	if (*powner)
		return -EBUSY;
	*powner = owner;
	return rc;
}
1892
EXPORT_SYMBOL_GPL(usb_hub_claim_port);
1893

1894
int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
1895
			 struct usb_dev_state *owner)
1896 1897
{
	int rc;
1898
	struct usb_dev_state **powner;
1899 1900 1901 1902 1903 1904 1905 1906 1907

	rc = find_port_owner(hdev, port1, &powner);
	if (rc)
		return rc;
	if (*powner != owner)
		return -ENOENT;
	*powner = NULL;
	return rc;
}
1908
EXPORT_SYMBOL_GPL(usb_hub_release_port);
1909

1910
void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
1911
{
1912
	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1913 1914
	int n;

L
Lan Tianyu 已提交
1915 1916 1917
	for (n = 0; n < hdev->maxchild; n++) {
		if (hub->ports[n]->port_owner == owner)
			hub->ports[n]->port_owner = NULL;
1918
	}
L
Lan Tianyu 已提交
1919

1920 1921 1922 1923 1924 1925 1926 1927 1928
}

/* The caller must hold udev's lock */
bool usb_device_is_owned(struct usb_device *udev)
{
	struct usb_hub *hub;

	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
		return false;
1929
	hub = usb_hub_to_struct_hub(udev->parent);
L
Lan Tianyu 已提交
1930
	return !!hub->ports[udev->portnum - 1]->port_owner;
1931 1932
}

L
Linus Torvalds 已提交
1933 1934
static void recursively_mark_NOTATTACHED(struct usb_device *udev)
{
1935
	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
L
Linus Torvalds 已提交
1936 1937 1938
	int i;

	for (i = 0; i < udev->maxchild; ++i) {
1939 1940
		if (hub->ports[i]->child)
			recursively_mark_NOTATTACHED(hub->ports[i]->child);
L
Linus Torvalds 已提交
1941
	}
1942
	if (udev->state == USB_STATE_SUSPENDED)
S
Sarah Sharp 已提交
1943
		udev->active_duration -= jiffies;
L
Linus Torvalds 已提交
1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971
	udev->state = USB_STATE_NOTATTACHED;
}

/**
 * usb_set_device_state - change a device's current state (usbcore, hcds)
 * @udev: pointer to device whose state should be changed
 * @new_state: new state value to be stored
 *
 * udev->state is _not_ fully protected by the device lock.  Although
 * most transitions are made only while holding the lock, the state can
 * can change to USB_STATE_NOTATTACHED at almost any time.  This
 * is so that devices can be marked as disconnected as soon as possible,
 * without having to wait for any semaphores to be released.  As a result,
 * all changes to any device's state must be protected by the
 * device_state_lock spinlock.
 *
 * Once a device has been added to the device tree, all changes to its state
 * should be made using this routine.  The state should _not_ be set directly.
 *
 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
 * Otherwise udev->state is set to new_state, and if new_state is
 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
 * to USB_STATE_NOTATTACHED.
 */
void usb_set_device_state(struct usb_device *udev,
		enum usb_device_state new_state)
{
	unsigned long flags;
1972
	int wakeup = -1;
L
Linus Torvalds 已提交
1973 1974 1975 1976

	spin_lock_irqsave(&device_state_lock, flags);
	if (udev->state == USB_STATE_NOTATTACHED)
		;	/* do nothing */
D
David Brownell 已提交
1977
	else if (new_state != USB_STATE_NOTATTACHED) {
1978 1979 1980 1981 1982

		/* root hub wakeup capabilities are managed out-of-band
		 * and may involve silicon errata ... ignore them here.
		 */
		if (udev->parent) {
1983 1984 1985 1986
			if (udev->state == USB_STATE_SUSPENDED
					|| new_state == USB_STATE_SUSPENDED)
				;	/* No change to wakeup settings */
			else if (new_state == USB_STATE_CONFIGURED)
1987 1988
				wakeup = udev->actconfig->desc.bmAttributes
					 & USB_CONFIG_ATT_WAKEUP;
1989
			else
1990
				wakeup = 0;
1991
		}
S
Sarah Sharp 已提交
1992 1993 1994 1995 1996 1997
		if (udev->state == USB_STATE_SUSPENDED &&
			new_state != USB_STATE_SUSPENDED)
			udev->active_duration -= jiffies;
		else if (new_state == USB_STATE_SUSPENDED &&
				udev->state != USB_STATE_SUSPENDED)
			udev->active_duration += jiffies;
1998
		udev->state = new_state;
D
David Brownell 已提交
1999
	} else
L
Linus Torvalds 已提交
2000 2001
		recursively_mark_NOTATTACHED(udev);
	spin_unlock_irqrestore(&device_state_lock, flags);
2002 2003
	if (wakeup >= 0)
		device_set_wakeup_capable(&udev->dev, wakeup);
L
Linus Torvalds 已提交
2004
}
2005
EXPORT_SYMBOL_GPL(usb_set_device_state);
L
Linus Torvalds 已提交
2006

2007
/*
2008 2009 2010 2011 2012 2013 2014
 * Choose a device number.
 *
 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
 * USB-2.0 buses they are also used as device addresses, however on
 * USB-3.0 buses the address is assigned by the controller hardware
 * and it usually is not the same as the device number.
 *
2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029
 * WUSB devices are simple: they have no hubs behind, so the mapping
 * device <-> virtual port number becomes 1:1. Why? to simplify the
 * life of the device connection logic in
 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
 * handshake we need to assign a temporary address in the unauthorized
 * space. For simplicity we use the first virtual port number found to
 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
 * and that becomes it's address [X < 128] or its unauthorized address
 * [X | 0x80].
 *
 * We add 1 as an offset to the one-based USB-stack port number
 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
 * 0 is reserved by USB for default address; (b) Linux's USB stack
 * uses always #1 for the root hub of the controller. So USB stack's
 * port #1, which is wusb virtual-port #0 has address #2.
2030 2031 2032 2033 2034
 *
 * Devices connected under xHCI are not as simple.  The host controller
 * supports virtualization, so the hardware assigns device addresses and
 * the HCD must setup data structures before issuing a set address
 * command to the hardware.
2035
 */
2036
static void choose_devnum(struct usb_device *udev)
L
Linus Torvalds 已提交
2037 2038 2039 2040 2041
{
	int		devnum;
	struct usb_bus	*bus = udev->bus;

	/* If khubd ever becomes multithreaded, this will need a lock */
2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052
	if (udev->wusb) {
		devnum = udev->portnum + 1;
		BUG_ON(test_bit(devnum, bus->devmap.devicemap));
	} else {
		/* Try to allocate the next devnum beginning at
		 * bus->devnum_next. */
		devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
					    bus->devnum_next);
		if (devnum >= 128)
			devnum = find_next_zero_bit(bus->devmap.devicemap,
						    128, 1);
2053
		bus->devnum_next = (devnum >= 127 ? 1 : devnum + 1);
2054
	}
L
Linus Torvalds 已提交
2055 2056 2057 2058 2059 2060
	if (devnum < 128) {
		set_bit(devnum, bus->devmap.devicemap);
		udev->devnum = devnum;
	}
}

2061
static void release_devnum(struct usb_device *udev)
L
Linus Torvalds 已提交
2062 2063 2064 2065 2066 2067 2068
{
	if (udev->devnum > 0) {
		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
		udev->devnum = -1;
	}
}

2069
static void update_devnum(struct usb_device *udev, int devnum)
2070 2071 2072 2073 2074 2075
{
	/* The address for a WUSB device is managed by wusbcore. */
	if (!udev->wusb)
		udev->devnum = devnum;
}

2076 2077 2078 2079 2080 2081 2082 2083 2084
static void hub_free_dev(struct usb_device *udev)
{
	struct usb_hcd *hcd = bus_to_hcd(udev->bus);

	/* Root hubs aren't real devices, so don't free HCD resources */
	if (hcd->driver->free_dev && udev->parent)
		hcd->driver->free_dev(hcd, udev);
}

2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096
static void hub_disconnect_children(struct usb_device *udev)
{
	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
	int i;

	/* Free up all the children before we remove this device */
	for (i = 0; i < udev->maxchild; i++) {
		if (hub->ports[i]->child)
			usb_disconnect(&hub->ports[i]->child);
	}
}

L
Linus Torvalds 已提交
2097 2098 2099 2100 2101 2102 2103 2104
/**
 * usb_disconnect - disconnect a device (usbcore-internal)
 * @pdev: pointer to device being disconnected
 * Context: !in_interrupt ()
 *
 * Something got disconnected. Get rid of it and all of its children.
 *
 * If *pdev is a normal device then the parent hub must already be locked.
2105 2106
 * If *pdev is a root hub then the caller must hold the usb_bus_list_lock,
 * which protects the set of root hubs as well as the list of buses.
L
Linus Torvalds 已提交
2107 2108 2109 2110 2111 2112 2113 2114
 *
 * Only hub drivers (including virtual root hub drivers for host
 * controllers) should ever call this.
 *
 * This call is synchronous, and may not be used in an interrupt context.
 */
void usb_disconnect(struct usb_device **pdev)
{
2115 2116
	struct usb_port *port_dev = NULL;
	struct usb_device *udev = *pdev;
P
Peter Chen 已提交
2117 2118
	struct usb_hub *hub = NULL;
	int port1 = 1;
L
Linus Torvalds 已提交
2119 2120 2121

	/* mark the device as inactive, so any further urb submissions for
	 * this device (and any of its children) will fail immediately.
L
Lucas De Marchi 已提交
2122
	 * this quiesces everything except pending urbs.
L
Linus Torvalds 已提交
2123 2124
	 */
	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2125 2126
	dev_info(&udev->dev, "USB disconnect, device number %d\n",
			udev->devnum);
L
Linus Torvalds 已提交
2127

2128 2129
	usb_lock_device(udev);

2130
	hub_disconnect_children(udev);
L
Linus Torvalds 已提交
2131 2132 2133 2134 2135

	/* deallocate hcd/hardware state ... nuking all pending urbs and
	 * cleaning up all state associated with the current configuration
	 * so that the hardware is now fully quiesced.
	 */
2136
	dev_dbg (&udev->dev, "unregistering device\n");
L
Linus Torvalds 已提交
2137
	usb_disable_device(udev, 0);
2138
	usb_hcd_synchronize_unlinks(udev);
L
Linus Torvalds 已提交
2139

2140
	if (udev->parent) {
2141 2142 2143
		port1 = udev->portnum;
		hub = usb_hub_to_struct_hub(udev->parent);
		port_dev = hub->ports[port1 - 1];
2144 2145 2146

		sysfs_remove_link(&udev->dev.kobj, "port");
		sysfs_remove_link(&port_dev->dev.kobj, "device");
2147

2148 2149 2150 2151 2152 2153
		/*
		 * As usb_port_runtime_resume() de-references udev, make
		 * sure no resumes occur during removal
		 */
		if (!test_and_set_bit(port1, hub->child_usage_bits))
			pm_runtime_get_sync(&port_dev->dev);
2154 2155
	}

A
Alan Stern 已提交
2156
	usb_remove_ep_devs(&udev->ep0);
2157 2158 2159
	usb_unlock_device(udev);

	/* Unregister the device.  The device driver is responsible
A
Alan Stern 已提交
2160 2161
	 * for de-configuring the device and invoking the remove-device
	 * notifier chain (used by usbfs and possibly others).
2162 2163
	 */
	device_del(&udev->dev);
2164

2165
	/* Free the device number and delete the parent's children[]
L
Linus Torvalds 已提交
2166 2167
	 * (or root_hub) pointer.
	 */
2168
	release_devnum(udev);
L
Linus Torvalds 已提交
2169 2170 2171 2172 2173 2174

	/* Avoid races with recursively_mark_NOTATTACHED() */
	spin_lock_irq(&device_state_lock);
	*pdev = NULL;
	spin_unlock_irq(&device_state_lock);

2175 2176 2177
	if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
		pm_runtime_put(&port_dev->dev);

2178 2179
	hub_free_dev(udev);

2180
	put_device(&udev->dev);
L
Linus Torvalds 已提交
2181 2182
}

2183
#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
L
Linus Torvalds 已提交
2184 2185 2186 2187
static void show_string(struct usb_device *udev, char *id, char *string)
{
	if (!string)
		return;
2188
	dev_info(&udev->dev, "%s: %s\n", id, string);
L
Linus Torvalds 已提交
2189 2190
}

2191 2192 2193 2194 2195
static void announce_device(struct usb_device *udev)
{
	dev_info(&udev->dev, "New USB device found, idVendor=%04x, idProduct=%04x\n",
		le16_to_cpu(udev->descriptor.idVendor),
		le16_to_cpu(udev->descriptor.idProduct));
2196 2197
	dev_info(&udev->dev,
		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
2198 2199 2200 2201 2202 2203 2204
		udev->descriptor.iManufacturer,
		udev->descriptor.iProduct,
		udev->descriptor.iSerialNumber);
	show_string(udev, "Product", udev->product);
	show_string(udev, "Manufacturer", udev->manufacturer);
	show_string(udev, "SerialNumber", udev->serial);
}
L
Linus Torvalds 已提交
2205
#else
2206
static inline void announce_device(struct usb_device *udev) { }
L
Linus Torvalds 已提交
2207 2208 2209
#endif


2210
/**
A
Alan Stern 已提交
2211
 * usb_enumerate_device_otg - FIXME (usbcore-internal)
2212 2213
 * @udev: newly addressed device (in ADDRESS state)
 *
A
Alan Stern 已提交
2214
 * Finish enumeration for On-The-Go devices
2215 2216
 *
 * Return: 0 if successful. A negative error code otherwise.
2217
 */
A
Alan Stern 已提交
2218
static int usb_enumerate_device_otg(struct usb_device *udev)
L
Linus Torvalds 已提交
2219
{
2220
	int err = 0;
L
Linus Torvalds 已提交
2221 2222 2223 2224 2225 2226 2227 2228 2229 2230

#ifdef	CONFIG_USB_OTG
	/*
	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
	 * to wake us after we've powered off VBUS; and HNP, switching roles
	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
	 */
	if (!udev->bus->is_b_host
			&& udev->config
			&& udev->parent == udev->bus->root_hub) {
F
Felipe Balbi 已提交
2231
		struct usb_otg_descriptor	*desc = NULL;
L
Linus Torvalds 已提交
2232 2233 2234 2235 2236 2237 2238
		struct usb_bus			*bus = udev->bus;

		/* descriptor may appear anywhere in config */
		if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
					le16_to_cpu(udev->config[0].desc.wTotalLength),
					USB_DT_OTG, (void **) &desc) == 0) {
			if (desc->bmAttributes & USB_OTG_HNP) {
2239
				unsigned		port1 = udev->portnum;
D
David Brownell 已提交
2240

L
Linus Torvalds 已提交
2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260
				dev_info(&udev->dev,
					"Dual-Role OTG device on %sHNP port\n",
					(port1 == bus->otg_port)
						? "" : "non-");

				/* enable HNP before suspend, it's simpler */
				if (port1 == bus->otg_port)
					bus->b_hnp_enable = 1;
				err = usb_control_msg(udev,
					usb_sndctrlpipe(udev, 0),
					USB_REQ_SET_FEATURE, 0,
					bus->b_hnp_enable
						? USB_DEVICE_B_HNP_ENABLE
						: USB_DEVICE_A_ALT_HNP_SUPPORT,
					0, NULL, 0, USB_CTRL_SET_TIMEOUT);
				if (err < 0) {
					/* OTG MESSAGE: report errors here,
					 * customize to match your product.
					 */
					dev_info(&udev->dev,
2261
						"can't set HNP mode: %d\n",
L
Linus Torvalds 已提交
2262 2263 2264 2265 2266 2267 2268
						err);
					bus->b_hnp_enable = 0;
				}
			}
		}
	}
#endif
2269 2270 2271 2272 2273
	return err;
}


/**
A
Alan Stern 已提交
2274
 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2275 2276 2277 2278 2279 2280 2281 2282 2283
 * @udev: newly addressed device (in ADDRESS state)
 *
 * This is only called by usb_new_device() and usb_authorize_device()
 * and FIXME -- all comments that apply to them apply here wrt to
 * environment.
 *
 * If the device is WUSB and not authorized, we don't attempt to read
 * the string descriptors, as they will be errored out by the device
 * until it has been authorized.
2284 2285
 *
 * Return: 0 if successful. A negative error code otherwise.
2286
 */
A
Alan Stern 已提交
2287
static int usb_enumerate_device(struct usb_device *udev)
2288 2289
{
	int err;
2290
	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
L
Linus Torvalds 已提交
2291

2292 2293 2294
	if (udev->config == NULL) {
		err = usb_get_configuration(udev);
		if (err < 0) {
2295 2296 2297
			if (err != -ENODEV)
				dev_err(&udev->dev, "can't read configurations, error %d\n",
						err);
2298
			return err;
2299 2300
		}
	}
2301 2302 2303 2304 2305 2306 2307

	/* read the standard strings and cache them if present */
	udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
	udev->manufacturer = usb_cache_string(udev,
					      udev->descriptor.iManufacturer);
	udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);

A
Alan Stern 已提交
2308
	err = usb_enumerate_device_otg(udev);
2309 2310 2311
	if (err < 0)
		return err;

2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324
	if (IS_ENABLED(CONFIG_USB_OTG_WHITELIST) && hcd->tpl_support &&
		!is_targeted(udev) && IS_ENABLED(CONFIG_USB_OTG)) {
		/* Maybe it can talk to us, though we can't talk to it.
		 * (Includes HNP test device.)
		 */
		if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
			err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
			if (err < 0)
				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
		}
		return -ENOTSUPP;
	}

2325 2326 2327
	usb_detect_interface_quirks(udev);

	return 0;
2328 2329
}

2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340
static void set_usb_port_removable(struct usb_device *udev)
{
	struct usb_device *hdev = udev->parent;
	struct usb_hub *hub;
	u8 port = udev->portnum;
	u16 wHubCharacteristics;
	bool removable = true;

	if (!hdev)
		return;

2341
	hub = usb_hub_to_struct_hub(udev->parent);
2342 2343 2344 2345 2346 2347 2348

	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);

	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
		return;

	if (hub_is_superspeed(hdev)) {
2349 2350
		if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
				& (1 << port))
2351 2352 2353 2354 2355 2356 2357 2358 2359 2360
			removable = false;
	} else {
		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
			removable = false;
	}

	if (removable)
		udev->removable = USB_DEVICE_REMOVABLE;
	else
		udev->removable = USB_DEVICE_FIXED;
2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376

	/*
	 * Platform firmware may have populated an alternative value for
	 * removable.  If the parent port has a known connect_type use
	 * that instead.
	 */
	switch (hub->ports[udev->portnum - 1]->connect_type) {
	case USB_PORT_CONNECT_TYPE_HOT_PLUG:
		udev->removable = USB_DEVICE_REMOVABLE;
		break;
	case USB_PORT_CONNECT_TYPE_HARD_WIRED:
		udev->removable = USB_DEVICE_FIXED;
		break;
	default: /* use what was set above */
		break;
	}
2377
}
2378 2379 2380 2381 2382

/**
 * usb_new_device - perform initial device setup (usbcore-internal)
 * @udev: newly addressed device (in ADDRESS state)
 *
A
Alan Stern 已提交
2383 2384
 * This is called with devices which have been detected but not fully
 * enumerated.  The device descriptor is available, but not descriptors
2385 2386 2387 2388 2389 2390 2391 2392 2393
 * for any device configuration.  The caller must have locked either
 * the parent hub (if udev is a normal device) or else the
 * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
 * udev has already been installed, but udev is not yet visible through
 * sysfs or other filesystem code.
 *
 * This call is synchronous, and may not be used in an interrupt context.
 *
 * Only the hub driver or root-hub registrar should ever call this.
2394 2395 2396 2397 2398
 *
 * Return: Whether the device is configured properly or not. Zero if the
 * interface was registered with the driver core; else a negative errno
 * value.
 *
2399 2400 2401 2402 2403
 */
int usb_new_device(struct usb_device *udev)
{
	int err;

2404 2405 2406 2407 2408 2409 2410 2411
	if (udev->parent) {
		/* Initialize non-root-hub device wakeup to disabled;
		 * device (un)configuration controls wakeup capable
		 * sysfs power/wakeup controls wakeup enabled/disabled
		 */
		device_init_wakeup(&udev->dev, 0);
	}

2412 2413
	/* Tell the runtime-PM framework the device is active */
	pm_runtime_set_active(&udev->dev);
2414
	pm_runtime_get_noresume(&udev->dev);
2415
	pm_runtime_use_autosuspend(&udev->dev);
2416 2417
	pm_runtime_enable(&udev->dev);

2418 2419 2420 2421 2422
	/* By default, forbid autosuspend for all devices.  It will be
	 * allowed for hubs during binding.
	 */
	usb_disable_autosuspend(udev);

A
Alan Stern 已提交
2423
	err = usb_enumerate_device(udev);	/* Read descriptors */
2424 2425
	if (err < 0)
		goto fail;
2426 2427 2428
	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
			udev->devnum, udev->bus->busnum,
			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2429 2430 2431 2432
	/* export the usbdev device-node for libusb */
	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));

A
Alan Stern 已提交
2433 2434
	/* Tell the world! */
	announce_device(udev);
2435

2436 2437 2438 2439 2440 2441 2442 2443
	if (udev->serial)
		add_device_randomness(udev->serial, strlen(udev->serial));
	if (udev->product)
		add_device_randomness(udev->product, strlen(udev->product));
	if (udev->manufacturer)
		add_device_randomness(udev->manufacturer,
				      strlen(udev->manufacturer));

2444
	device_enable_async_suspend(&udev->dev);
2445

2446
	/* check whether the hub or firmware marks this port as non-removable */
2447 2448 2449
	if (udev->parent)
		set_usb_port_removable(udev);

2450
	/* Register the device.  The device driver is responsible
A
Alan Stern 已提交
2451 2452
	 * for configuring the device and invoking the add-device
	 * notifier chain (used by usbfs and possibly others).
2453
	 */
2454
	err = device_add(&udev->dev);
L
Linus Torvalds 已提交
2455 2456 2457 2458
	if (err) {
		dev_err(&udev->dev, "can't device_add, error %d\n", err);
		goto fail;
	}
2459

2460 2461
	/* Create link files between child device and usb port device. */
	if (udev->parent) {
2462
		struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
2463 2464
		int port1 = udev->portnum;
		struct usb_port	*port_dev = hub->ports[port1 - 1];
2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476

		err = sysfs_create_link(&udev->dev.kobj,
				&port_dev->dev.kobj, "port");
		if (err)
			goto fail;

		err = sysfs_create_link(&port_dev->dev.kobj,
				&udev->dev.kobj, "device");
		if (err) {
			sysfs_remove_link(&udev->dev.kobj, "port");
			goto fail;
		}
2477

2478 2479
		if (!test_and_set_bit(port1, hub->child_usage_bits))
			pm_runtime_get_sync(&port_dev->dev);
2480 2481
	}

A
Alan Stern 已提交
2482
	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2483 2484
	usb_mark_last_busy(udev);
	pm_runtime_put_sync_autosuspend(&udev->dev);
2485
	return err;
L
Linus Torvalds 已提交
2486 2487 2488

fail:
	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2489 2490
	pm_runtime_disable(&udev->dev);
	pm_runtime_set_suspended(&udev->dev);
2491
	return err;
L
Linus Torvalds 已提交
2492 2493
}

2494 2495

/**
R
Randy Dunlap 已提交
2496 2497 2498 2499 2500
 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
 * @usb_dev: USB device
 *
 * Move the USB device to a very basic state where interfaces are disabled
 * and the device is in fact unconfigured and unusable.
2501 2502 2503
 *
 * We share a lock (that we have) with device_del(), so we need to
 * defer its call.
2504 2505
 *
 * Return: 0.
2506 2507 2508 2509 2510 2511
 */
int usb_deauthorize_device(struct usb_device *usb_dev)
{
	usb_lock_device(usb_dev);
	if (usb_dev->authorized == 0)
		goto out_unauthorized;
2512

2513 2514
	usb_dev->authorized = 0;
	usb_set_configuration(usb_dev, -1);
2515

2516 2517 2518 2519 2520 2521 2522 2523 2524
out_unauthorized:
	usb_unlock_device(usb_dev);
	return 0;
}


int usb_authorize_device(struct usb_device *usb_dev)
{
	int result = 0, c;
2525

2526 2527 2528
	usb_lock_device(usb_dev);
	if (usb_dev->authorized == 1)
		goto out_authorized;
2529

2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541
	result = usb_autoresume_device(usb_dev);
	if (result < 0) {
		dev_err(&usb_dev->dev,
			"can't autoresume for authorization: %d\n", result);
		goto error_autoresume;
	}
	result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
	if (result < 0) {
		dev_err(&usb_dev->dev, "can't re-read device descriptor for "
			"authorization: %d\n", result);
		goto error_device_descriptor;
	}
2542

2543 2544 2545 2546
	usb_dev->authorized = 1;
	/* Choose and set the configuration.  This registers the interfaces
	 * with the driver core and lets interface drivers bind to them.
	 */
2547
	c = usb_choose_configuration(usb_dev);
2548 2549 2550 2551 2552 2553 2554 2555 2556 2557
	if (c >= 0) {
		result = usb_set_configuration(usb_dev, c);
		if (result) {
			dev_err(&usb_dev->dev,
				"can't set config #%d, error %d\n", c, result);
			/* This need not be fatal.  The user can try to
			 * set other configurations. */
		}
	}
	dev_info(&usb_dev->dev, "authorized to connect\n");
2558

2559
error_device_descriptor:
2560
	usb_autosuspend_device(usb_dev);
2561 2562
error_autoresume:
out_authorized:
2563
	usb_unlock_device(usb_dev);	/* complements locktree */
2564 2565 2566 2567
	return result;
}


2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578
/* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
static unsigned hub_is_wusb(struct usb_hub *hub)
{
	struct usb_hcd *hcd;
	if (hub->hdev->parent != NULL)  /* not a root hub? */
		return 0;
	hcd = container_of(hub->hdev->bus, struct usb_hcd, self);
	return hcd->wireless;
}


L
Linus Torvalds 已提交
2579 2580 2581 2582
#define PORT_RESET_TRIES	5
#define SET_ADDRESS_TRIES	2
#define GET_DESCRIPTOR_TRIES	2
#define SET_CONFIG_TRIES	(2 * (use_both_schemes + 1))
2583
#define USE_NEW_SCHEME(i)	((i) / 2 == (int)old_scheme_first)
L
Linus Torvalds 已提交
2584 2585 2586

#define HUB_ROOT_RESET_TIME	50	/* times are in msec */
#define HUB_SHORT_RESET_TIME	10
A
Andiry Xu 已提交
2587
#define HUB_BH_RESET_TIME	50
L
Linus Torvalds 已提交
2588
#define HUB_LONG_RESET_TIME	200
S
Sarah Sharp 已提交
2589
#define HUB_RESET_TIMEOUT	800
L
Linus Torvalds 已提交
2590

2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605
/*
 * "New scheme" enumeration causes an extra state transition to be
 * exposed to an xhci host and causes USB3 devices to receive control
 * commands in the default state.  This has been seen to cause
 * enumeration failures, so disable this enumeration scheme for USB3
 * devices.
 */
static bool use_new_scheme(struct usb_device *udev, int retry)
{
	if (udev->speed == USB_SPEED_SUPER)
		return false;

	return USE_NEW_SCHEME(retry);
}

2606 2607 2608
static int hub_port_reset(struct usb_hub *hub, int port1,
			struct usb_device *udev, unsigned int delay, bool warm);

2609
/* Is a USB 3.0 port in the Inactive or Compliance Mode state?
2610 2611
 * Port worm reset is required to recover
 */
2612 2613
static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
		u16 portstatus)
2614
{
2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625
	u16 link_state;

	if (!hub_is_superspeed(hub->hdev))
		return false;

	if (test_bit(port1, hub->warm_reset_bits))
		return true;

	link_state = portstatus & USB_PORT_STAT_LINK_STATE;
	return link_state == USB_SS_PORT_LS_SS_INACTIVE
		|| link_state == USB_SS_PORT_LS_COMP_MOD;
2626 2627
}

L
Linus Torvalds 已提交
2628
static int hub_port_wait_reset(struct usb_hub *hub, int port1,
A
Andiry Xu 已提交
2629
			struct usb_device *udev, unsigned int delay, bool warm)
L
Linus Torvalds 已提交
2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645
{
	int delay_time, ret;
	u16 portstatus;
	u16 portchange;

	for (delay_time = 0;
			delay_time < HUB_RESET_TIMEOUT;
			delay_time += delay) {
		/* wait to give the device a chance to reset */
		msleep(delay);

		/* read and decode port status */
		ret = hub_port_status(hub, port1, &portstatus, &portchange);
		if (ret < 0)
			return ret;

2646
		/* The port state is unknown until the reset completes. */
S
Sarah Sharp 已提交
2647 2648
		if (!(portstatus & USB_PORT_STAT_RESET))
			break;
L
Linus Torvalds 已提交
2649 2650 2651 2652 2653

		/* switch to the long delay after two short delay failures */
		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
			delay = HUB_LONG_RESET_TIME;

2654 2655 2656
		dev_dbg(&hub->ports[port1 - 1]->dev,
				"not %sreset yet, waiting %dms\n",
				warm ? "warm " : "", delay);
L
Linus Torvalds 已提交
2657 2658
	}

S
Sarah Sharp 已提交
2659 2660 2661
	if ((portstatus & USB_PORT_STAT_RESET))
		return -EBUSY;

2662
	if (hub_port_warm_reset_required(hub, port1, portstatus))
S
Sarah Sharp 已提交
2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693
		return -ENOTCONN;

	/* Device went away? */
	if (!(portstatus & USB_PORT_STAT_CONNECTION))
		return -ENOTCONN;

	/* bomb out completely if the connection bounced.  A USB 3.0
	 * connection may bounce if multiple warm resets were issued,
	 * but the device may have successfully re-connected. Ignore it.
	 */
	if (!hub_is_superspeed(hub->hdev) &&
			(portchange & USB_PORT_STAT_C_CONNECTION))
		return -ENOTCONN;

	if (!(portstatus & USB_PORT_STAT_ENABLE))
		return -EBUSY;

	if (!udev)
		return 0;

	if (hub_is_wusb(hub))
		udev->speed = USB_SPEED_WIRELESS;
	else if (hub_is_superspeed(hub->hdev))
		udev->speed = USB_SPEED_SUPER;
	else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
		udev->speed = USB_SPEED_HIGH;
	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
		udev->speed = USB_SPEED_LOW;
	else
		udev->speed = USB_SPEED_FULL;
	return 0;
L
Linus Torvalds 已提交
2694 2695
}

A
Andiry Xu 已提交
2696
static void hub_port_finish_reset(struct usb_hub *hub, int port1,
2697
			struct usb_device *udev, int *status)
A
Andiry Xu 已提交
2698 2699 2700
{
	switch (*status) {
	case 0:
2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711
		/* TRSTRCY = 10 ms; plus some extra */
		msleep(10 + 40);
		if (udev) {
			struct usb_hcd *hcd = bus_to_hcd(udev->bus);

			update_devnum(udev, 0);
			/* The xHC may think the device is already reset,
			 * so ignore the status.
			 */
			if (hcd->driver->reset_device)
				hcd->driver->reset_device(hcd, udev);
A
Andiry Xu 已提交
2712 2713 2714 2715
		}
		/* FALL THROUGH */
	case -ENOTCONN:
	case -ENODEV:
2716
		usb_clear_port_feature(hub->hdev,
A
Andiry Xu 已提交
2717
				port1, USB_PORT_FEAT_C_RESET);
2718
		if (hub_is_superspeed(hub->hdev)) {
2719
			usb_clear_port_feature(hub->hdev, port1,
A
Andiry Xu 已提交
2720
					USB_PORT_FEAT_C_BH_PORT_RESET);
2721
			usb_clear_port_feature(hub->hdev, port1,
A
Andiry Xu 已提交
2722
					USB_PORT_FEAT_C_PORT_LINK_STATE);
2723
			usb_clear_port_feature(hub->hdev, port1,
2724
					USB_PORT_FEAT_C_CONNECTION);
2725
		}
2726
		if (udev)
A
Andiry Xu 已提交
2727 2728 2729 2730 2731 2732 2733 2734
			usb_set_device_state(udev, *status
					? USB_STATE_NOTATTACHED
					: USB_STATE_DEFAULT);
		break;
	}
}

/* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
L
Linus Torvalds 已提交
2735
static int hub_port_reset(struct usb_hub *hub, int port1,
A
Andiry Xu 已提交
2736
			struct usb_device *udev, unsigned int delay, bool warm)
L
Linus Torvalds 已提交
2737 2738
{
	int i, status;
2739
	u16 portchange, portstatus;
2740
	struct usb_port *port_dev = hub->ports[port1 - 1];
L
Linus Torvalds 已提交
2741

2742 2743
	if (!hub_is_superspeed(hub->hdev)) {
		if (warm) {
A
Andiry Xu 已提交
2744 2745 2746 2747
			dev_err(hub->intfdev, "only USB3 hub support "
						"warm reset\n");
			return -EINVAL;
		}
2748 2749 2750 2751
		/* Block EHCI CF initialization during the port reset.
		 * Some companion controllers don't like it when they mix.
		 */
		down_read(&ehci_cf_port_reset_rwsem);
2752 2753 2754 2755 2756 2757 2758 2759 2760 2761
	} else if (!warm) {
		/*
		 * If the caller hasn't explicitly requested a warm reset,
		 * double check and see if one is needed.
		 */
		status = hub_port_status(hub, port1,
					&portstatus, &portchange);
		if (status < 0)
			goto done;

2762
		if (hub_port_warm_reset_required(hub, port1, portstatus))
2763
			warm = true;
A
Andiry Xu 已提交
2764
	}
2765
	clear_bit(port1, hub->warm_reset_bits);
2766

L
Linus Torvalds 已提交
2767 2768
	/* Reset the port */
	for (i = 0; i < PORT_RESET_TRIES; i++) {
A
Andiry Xu 已提交
2769 2770 2771
		status = set_port_feature(hub->hdev, port1, (warm ?
					USB_PORT_FEAT_BH_PORT_RESET :
					USB_PORT_FEAT_RESET));
2772 2773 2774
		if (status == -ENODEV) {
			;	/* The hub is gone */
		} else if (status) {
2775 2776 2777
			dev_err(&port_dev->dev,
					"cannot %sreset (err = %d)\n",
					warm ? "warm " : "", status);
A
Andiry Xu 已提交
2778 2779 2780
		} else {
			status = hub_port_wait_reset(hub, port1, udev, delay,
								warm);
2781
			if (status && status != -ENOTCONN && status != -ENODEV)
L
Linus Torvalds 已提交
2782 2783 2784 2785 2786
				dev_dbg(hub->intfdev,
						"port_wait_reset: err = %d\n",
						status);
		}

2787
		/* Check for disconnect or reset */
A
Andiry Xu 已提交
2788
		if (status == 0 || status == -ENOTCONN || status == -ENODEV) {
2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801
			hub_port_finish_reset(hub, port1, udev, &status);

			if (!hub_is_superspeed(hub->hdev))
				goto done;

			/*
			 * If a USB 3.0 device migrates from reset to an error
			 * state, re-issue the warm reset.
			 */
			if (hub_port_status(hub, port1,
					&portstatus, &portchange) < 0)
				goto done;

2802 2803
			if (!hub_port_warm_reset_required(hub, port1,
					portstatus))
2804 2805 2806 2807 2808 2809 2810
				goto done;

			/*
			 * If the port is in SS.Inactive or Compliance Mode, the
			 * hot or warm reset failed.  Try another warm reset.
			 */
			if (!warm) {
2811 2812
				dev_dbg(&port_dev->dev,
						"hot reset failed, warm reset\n");
2813 2814
				warm = true;
			}
L
Linus Torvalds 已提交
2815 2816
		}

2817 2818 2819
		dev_dbg(&port_dev->dev,
				"not enabled, trying %sreset again...\n",
				warm ? "warm " : "");
L
Linus Torvalds 已提交
2820 2821 2822
		delay = HUB_LONG_RESET_TIME;
	}

2823
	dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
L
Linus Torvalds 已提交
2824

A
Andiry Xu 已提交
2825
done:
2826
	if (!hub_is_superspeed(hub->hdev))
A
Andiry Xu 已提交
2827
		up_read(&ehci_cf_port_reset_rwsem);
2828

A
Andiry Xu 已提交
2829
	return status;
2830 2831
}

2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847
/* Check if a port is power on */
static int port_is_power_on(struct usb_hub *hub, unsigned portstatus)
{
	int ret = 0;

	if (hub_is_superspeed(hub->hdev)) {
		if (portstatus & USB_SS_PORT_STAT_POWER)
			ret = 1;
	} else {
		if (portstatus & USB_PORT_STAT_POWER)
			ret = 1;
	}

	return ret;
}

D
Dan Williams 已提交
2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861
static void usb_lock_port(struct usb_port *port_dev)
		__acquires(&port_dev->status_lock)
{
	mutex_lock(&port_dev->status_lock);
	__acquire(&port_dev->status_lock);
}

static void usb_unlock_port(struct usb_port *port_dev)
		__releases(&port_dev->status_lock)
{
	mutex_unlock(&port_dev->status_lock);
	__release(&port_dev->status_lock);
}

A
Alan Stern 已提交
2862
#ifdef	CONFIG_PM
L
Linus Torvalds 已提交
2863

2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879
/* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
{
	int ret = 0;

	if (hub_is_superspeed(hub->hdev)) {
		if ((portstatus & USB_PORT_STAT_LINK_STATE)
				== USB_SS_PORT_LS_U3)
			ret = 1;
	} else {
		if (portstatus & USB_PORT_STAT_SUSPEND)
			ret = 1;
	}

	return ret;
}
2880 2881 2882 2883 2884 2885 2886 2887

/* Determine whether the device on a port is ready for a normal resume,
 * is ready for a reset-resume, or should be disconnected.
 */
static int check_port_resume_type(struct usb_device *udev,
		struct usb_hub *hub, int port1,
		int status, unsigned portchange, unsigned portstatus)
{
2888 2889
	struct usb_port *port_dev = hub->ports[port1 - 1];

2890 2891 2892 2893 2894
	/* Is a warm reset needed to recover the connection? */
	if (status == 0 && udev->reset_resume
		&& hub_port_warm_reset_required(hub, port1, portstatus)) {
		/* pass */;
	}
2895
	/* Is the device still present? */
2896
	else if (status || port_is_suspended(hub, portstatus) ||
2897 2898
			!port_is_power_on(hub, portstatus) ||
			!(portstatus & USB_PORT_STAT_CONNECTION)) {
2899 2900 2901 2902
		if (status >= 0)
			status = -ENODEV;
	}

2903 2904 2905 2906 2907 2908 2909 2910 2911
	/* Can't do a normal resume if the port isn't enabled,
	 * so try a reset-resume instead.
	 */
	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
		if (udev->persist_enabled)
			udev->reset_resume = 1;
		else
			status = -ENODEV;
	}
2912 2913

	if (status) {
2914 2915
		dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
				portchange, portstatus, status);
2916 2917 2918 2919
	} else if (udev->reset_resume) {

		/* Late port handoff can set status-change bits */
		if (portchange & USB_PORT_STAT_C_CONNECTION)
2920
			usb_clear_port_feature(hub->hdev, port1,
2921 2922
					USB_PORT_FEAT_C_CONNECTION);
		if (portchange & USB_PORT_STAT_C_ENABLE)
2923
			usb_clear_port_feature(hub->hdev, port1,
2924 2925 2926 2927 2928 2929
					USB_PORT_FEAT_C_ENABLE);
	}

	return status;
}

2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973
int usb_disable_ltm(struct usb_device *udev)
{
	struct usb_hcd *hcd = bus_to_hcd(udev->bus);

	/* Check if the roothub and device supports LTM. */
	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
			!usb_device_supports_ltm(udev))
		return 0;

	/* Clear Feature LTM Enable can only be sent if the device is
	 * configured.
	 */
	if (!udev->actconfig)
		return 0;

	return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
			USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
			USB_CTRL_SET_TIMEOUT);
}
EXPORT_SYMBOL_GPL(usb_disable_ltm);

void usb_enable_ltm(struct usb_device *udev)
{
	struct usb_hcd *hcd = bus_to_hcd(udev->bus);

	/* Check if the roothub and device supports LTM. */
	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
			!usb_device_supports_ltm(udev))
		return;

	/* Set Feature LTM Enable can only be sent if the device is
	 * configured.
	 */
	if (!udev->actconfig)
		return;

	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
			USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
			USB_CTRL_SET_TIMEOUT);
}
EXPORT_SYMBOL_GPL(usb_enable_ltm);

2974
/*
2975
 * usb_enable_remote_wakeup - enable remote wakeup for a device
2976 2977
 * @udev: target device
 *
2978 2979 2980 2981 2982
 * For USB-2 devices: Set the device's remote wakeup feature.
 *
 * For USB-3 devices: Assume there's only one function on the device and
 * enable remote wake for the first interface.  FIXME if the interface
 * association descriptor shows there's more than one function.
2983
 */
2984
static int usb_enable_remote_wakeup(struct usb_device *udev)
2985
{
2986 2987 2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016 3017 3018
	if (udev->speed < USB_SPEED_SUPER)
		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
				USB_CTRL_SET_TIMEOUT);
	else
		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
				USB_INTRF_FUNC_SUSPEND,
				USB_INTRF_FUNC_SUSPEND_RW |
					USB_INTRF_FUNC_SUSPEND_LP,
				NULL, 0, USB_CTRL_SET_TIMEOUT);
}

/*
 * usb_disable_remote_wakeup - disable remote wakeup for a device
 * @udev: target device
 *
 * For USB-2 devices: Clear the device's remote wakeup feature.
 *
 * For USB-3 devices: Assume there's only one function on the device and
 * disable remote wake for the first interface.  FIXME if the interface
 * association descriptor shows there's more than one function.
 */
static int usb_disable_remote_wakeup(struct usb_device *udev)
{
	if (udev->speed < USB_SPEED_SUPER)
		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
				USB_CTRL_SET_TIMEOUT);
	else
		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3019 3020 3021 3022
				USB_REQ_CLEAR_FEATURE, USB_RECIP_INTERFACE,
				USB_INTRF_FUNC_SUSPEND,	0, NULL, 0,
				USB_CTRL_SET_TIMEOUT);
}
L
Linus Torvalds 已提交
3023

3024 3025 3026 3027 3028 3029 3030 3031 3032
/* Count of wakeup-enabled devices at or below udev */
static unsigned wakeup_enabled_descendants(struct usb_device *udev)
{
	struct usb_hub *hub = usb_hub_to_struct_hub(udev);

	return udev->do_remote_wakeup +
			(hub ? hub->wakeup_enabled_descendants : 0);
}

L
Linus Torvalds 已提交
3033
/*
A
Alan Stern 已提交
3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046
 * usb_port_suspend - suspend a usb device's upstream port
 * @udev: device that's no longer in active use, not a root hub
 * Context: must be able to sleep; device not locked; pm locks held
 *
 * Suspends a USB device that isn't in active use, conserving power.
 * Devices may wake out of a suspend, if anything important happens,
 * using the remote wakeup mechanism.  They may also be taken out of
 * suspend by the host, using usb_port_resume().  It's also routine
 * to disconnect devices while they are suspended.
 *
 * This only affects the USB hardware for a device; its interfaces
 * (and, for hubs, child devices) must already have been suspended.
 *
L
Linus Torvalds 已提交
3047 3048 3049 3050 3051 3052 3053 3054
 * Selective port suspend reduces power; most suspended devices draw
 * less than 500 uA.  It's also used in OTG, along with remote wakeup.
 * All devices below the suspended port are also suspended.
 *
 * Devices leave suspend state when the host wakes them up.  Some devices
 * also support "remote wakeup", where the device can activate the USB
 * tree above them to deliver data, such as a keypress or packet.  In
 * some cases, this wakes the USB host.
A
Alan Stern 已提交
3055 3056 3057 3058 3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070 3071 3072
 *
 * Suspending OTG devices may trigger HNP, if that's been enabled
 * between a pair of dual-role devices.  That will change roles, such
 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
 *
 * Devices on USB hub ports have only one "suspend" state, corresponding
 * to ACPI D2, "may cause the device to lose some context".
 * State transitions include:
 *
 *   - suspend, resume ... when the VBUS power link stays live
 *   - suspend, disconnect ... VBUS lost
 *
 * Once VBUS drop breaks the circuit, the port it's using has to go through
 * normal re-enumeration procedures, starting with enabling VBUS power.
 * Other than re-initializing the hub (plug/unplug, except for root hubs),
 * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
 * timer, no SRP, no requests through sysfs.
 *
3073 3074
 * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
 * suspended until their bus goes into global suspend (i.e., the root
3075 3076 3077
 * hub is suspended).  Nevertheless, we change @udev->state to
 * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
 * upstream port setting is stored in @udev->port_is_suspended.
A
Alan Stern 已提交
3078 3079
 *
 * Returns 0 on success, else negative errno.
L
Linus Torvalds 已提交
3080
 */
A
Alan Stern 已提交
3081
int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
L
Linus Torvalds 已提交
3082
{
3083 3084
	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
	struct usb_port *port_dev = hub->ports[udev->portnum - 1];
A
Alan Stern 已提交
3085 3086
	int		port1 = udev->portnum;
	int		status;
3087
	bool		really_suspend = true;
L
Linus Torvalds 已提交
3088

D
Dan Williams 已提交
3089 3090
	usb_lock_port(port_dev);

L
Linus Torvalds 已提交
3091 3092 3093 3094 3095 3096
	/* enable remote wakeup when appropriate; this lets the device
	 * wake up the upstream hub (including maybe the root hub).
	 *
	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
	 * we don't explicitly enable it here.
	 */
3097
	if (udev->do_remote_wakeup) {
3098
		status = usb_enable_remote_wakeup(udev);
3099
		if (status) {
A
Alan Stern 已提交
3100 3101
			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
					status);
3102
			/* bail if autosuspend is requested */
3103
			if (PMSG_IS_AUTO(msg))
3104
				goto err_wakeup;
3105
		}
L
Linus Torvalds 已提交
3106 3107
	}

A
Andiry Xu 已提交
3108 3109 3110 3111
	/* disable USB2 hardware LPM */
	if (udev->usb2_hw_lpm_enabled == 1)
		usb_set_usb2_hardware_lpm(udev, 0);

3112
	if (usb_disable_ltm(udev)) {
3113 3114 3115 3116
		dev_err(&udev->dev, "Failed to disable LTM before suspend\n.");
		status = -ENOMEM;
		if (PMSG_IS_AUTO(msg))
			goto err_ltm;
3117
	}
3118
	if (usb_unlocked_disable_lpm(udev)) {
3119 3120 3121 3122
		dev_err(&udev->dev, "Failed to disable LPM before suspend\n.");
		status = -ENOMEM;
		if (PMSG_IS_AUTO(msg))
			goto err_lpm3;
3123 3124
	}

L
Linus Torvalds 已提交
3125
	/* see 7.1.7.6 */
3126
	if (hub_is_superspeed(hub->hdev))
3127
		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
3128

3129 3130 3131 3132 3133
	/*
	 * For system suspend, we do not need to enable the suspend feature
	 * on individual USB-2 ports.  The devices will automatically go
	 * into suspend a few ms after the root hub stops sending packets.
	 * The USB 2.0 spec calls this "global suspend".
3134 3135 3136 3137 3138
	 *
	 * However, many USB hubs have a bug: They don't relay wakeup requests
	 * from a downstream port if the port's suspend feature isn't on.
	 * Therefore we will turn on the suspend feature if udev or any of its
	 * descendants is enabled for remote wakeup.
3139
	 */
3140 3141 3142
	else if (PMSG_IS_AUTO(msg) || wakeup_enabled_descendants(udev) > 0)
		status = set_port_feature(hub->hdev, port1,
				USB_PORT_FEAT_SUSPEND);
3143 3144 3145 3146
	else {
		really_suspend = false;
		status = 0;
	}
L
Linus Torvalds 已提交
3147
	if (status) {
3148
		dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
3149

3150 3151 3152 3153 3154
		/* Try to enable USB3 LPM and LTM again */
		usb_unlocked_enable_lpm(udev);
 err_lpm3:
		usb_enable_ltm(udev);
 err_ltm:
3155 3156 3157 3158
		/* Try to enable USB2 hardware LPM again */
		if (udev->usb2_hw_lpm_capable == 1)
			usb_set_usb2_hardware_lpm(udev, 1);

3159 3160 3161
		if (udev->do_remote_wakeup)
			(void) usb_disable_remote_wakeup(udev);
 err_wakeup:
3162

3163
		/* System sleep transitions should never fail */
3164
		if (!PMSG_IS_AUTO(msg))
3165
			status = 0;
L
Linus Torvalds 已提交
3166
	} else {
3167 3168 3169
		dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
				(PMSG_IS_AUTO(msg) ? "auto-" : ""),
				udev->do_remote_wakeup);
3170 3171
		if (really_suspend) {
			udev->port_is_suspended = 1;
3172 3173

			/* device has up to 10 msec to fully suspend */
3174 3175
			msleep(10);
		}
3176
		usb_set_device_state(udev, USB_STATE_SUSPENDED);
L
Linus Torvalds 已提交
3177
	}
3178

3179 3180
	if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
			&& test_and_clear_bit(port1, hub->child_usage_bits))
3181
		pm_runtime_put_sync(&port_dev->dev);
3182

3183
	usb_mark_last_busy(hub->hdev);
D
Dan Williams 已提交
3184 3185

	usb_unlock_port(port_dev);
L
Linus Torvalds 已提交
3186 3187 3188 3189
	return status;
}

/*
3190 3191
 * If the USB "suspend" state is in use (rather than "global suspend"),
 * many devices will be individually taken out of suspend state using
3192
 * special "resume" signaling.  This routine kicks in shortly after
L
Linus Torvalds 已提交
3193 3194 3195
 * hardware resume signaling is finished, either because of selective
 * resume (by host) or remote wakeup (by device) ... now see what changed
 * in the tree that's rooted at this device.
3196 3197 3198
 *
 * If @udev->reset_resume is set then the device is reset before the
 * status check is done.
L
Linus Torvalds 已提交
3199
 */
3200
static int finish_port_resume(struct usb_device *udev)
L
Linus Torvalds 已提交
3201
{
3202
	int	status = 0;
3203
	u16	devstatus = 0;
L
Linus Torvalds 已提交
3204 3205

	/* caller owns the udev device lock */
3206 3207
	dev_dbg(&udev->dev, "%s\n",
		udev->reset_resume ? "finish reset-resume" : "finish resume");
L
Linus Torvalds 已提交
3208 3209 3210 3211 3212 3213 3214 3215 3216 3217

	/* usb ch9 identifies four variants of SUSPENDED, based on what
	 * state the device resumes to.  Linux currently won't see the
	 * first two on the host side; they'd be inside hub_port_init()
	 * during many timeouts, but khubd can't suspend until later.
	 */
	usb_set_device_state(udev, udev->actconfig
			? USB_STATE_CONFIGURED
			: USB_STATE_ADDRESS);

3218 3219 3220 3221 3222
	/* 10.5.4.5 says not to reset a suspended port if the attached
	 * device is enabled for remote wakeup.  Hence the reset
	 * operation is carried out here, after the port has been
	 * resumed.
	 */
3223 3224 3225 3226 3227 3228 3229
	if (udev->reset_resume) {
		/*
		 * If the device morphs or switches modes when it is reset,
		 * we don't want to perform a reset-resume.  We'll fail the
		 * resume, which will cause a logical disconnect, and then
		 * the device will be rediscovered.
		 */
3230
 retry_reset_resume:
3231 3232 3233 3234 3235
		if (udev->quirks & USB_QUIRK_RESET)
			status = -ENODEV;
		else
			status = usb_reset_and_verify_device(udev);
	}
3236

3237 3238
	/* 10.5.4.5 says be sure devices in the tree are still there.
	 * For now let's assume the device didn't go crazy on resume,
L
Linus Torvalds 已提交
3239 3240
	 * and device drivers will know about any resume quirks.
	 */
3241
	if (status == 0) {
3242
		devstatus = 0;
3243
		status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
3244 3245 3246 3247 3248 3249 3250

		/* If a normal resume failed, try doing a reset-resume */
		if (status && !udev->reset_resume && udev->persist_enabled) {
			dev_dbg(&udev->dev, "retry with reset-resume\n");
			udev->reset_resume = 1;
			goto retry_reset_resume;
		}
3251
	}
3252

A
Alan Stern 已提交
3253 3254 3255
	if (status) {
		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
				status);
3256 3257 3258 3259 3260 3261 3262
	/*
	 * There are a few quirky devices which violate the standard
	 * by claiming to have remote wakeup enabled after a reset,
	 * which crash if the feature is cleared, hence check for
	 * udev->reset_resume
	 */
	} else if (udev->actconfig && !udev->reset_resume) {
3263
		if (udev->speed < USB_SPEED_SUPER) {
3264
			if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
3265
				status = usb_disable_remote_wakeup(udev);
3266 3267 3268 3269 3270
		} else {
			status = usb_get_status(udev, USB_RECIP_INTERFACE, 0,
					&devstatus);
			if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
					| USB_INTRF_STAT_FUNC_RW))
3271
				status = usb_disable_remote_wakeup(udev);
3272
		}
3273 3274 3275 3276 3277

		if (status)
			dev_dbg(&udev->dev,
				"disable remote wakeup, status %d\n",
				status);
L
Linus Torvalds 已提交
3278 3279 3280 3281 3282
		status = 0;
	}
	return status;
}

3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319
/*
 * There are some SS USB devices which take longer time for link training.
 * XHCI specs 4.19.4 says that when Link training is successful, port
 * sets CSC bit to 1. So if SW reads port status before successful link
 * training, then it will not find device to be present.
 * USB Analyzer log with such buggy devices show that in some cases
 * device switch on the RX termination after long delay of host enabling
 * the VBUS. In few other cases it has been seen that device fails to
 * negotiate link training in first attempt. It has been
 * reported till now that few devices take as long as 2000 ms to train
 * the link after host enabling its VBUS and termination. Following
 * routine implements a 2000 ms timeout for link training. If in a case
 * link trains before timeout, loop will exit earlier.
 *
 * FIXME: If a device was connected before suspend, but was removed
 * while system was asleep, then the loop in the following routine will
 * only exit at timeout.
 *
 * This routine should only be called when persist is enabled for a SS
 * device.
 */
static int wait_for_ss_port_enable(struct usb_device *udev,
		struct usb_hub *hub, int *port1,
		u16 *portchange, u16 *portstatus)
{
	int status = 0, delay_ms = 0;

	while (delay_ms < 2000) {
		if (status || *portstatus & USB_PORT_STAT_CONNECTION)
			break;
		msleep(20);
		delay_ms += 20;
		status = hub_port_status(hub, *port1, portstatus, portchange);
	}
	return status;
}

A
Alan Stern 已提交
3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330
/*
 * usb_port_resume - re-activate a suspended usb device's upstream port
 * @udev: device to re-activate, not a root hub
 * Context: must be able to sleep; device not locked; pm locks held
 *
 * This will re-activate the suspended device, increasing power usage
 * while letting drivers communicate again with its endpoints.
 * USB resume explicitly guarantees that the power session between
 * the host and the device is the same as it was when the device
 * suspended.
 *
3331 3332
 * If @udev->reset_resume is set then this routine won't check that the
 * port is still enabled.  Furthermore, finish_port_resume() above will
3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343
 * reset @udev.  The end result is that a broken power session can be
 * recovered and @udev will appear to persist across a loss of VBUS power.
 *
 * For example, if a host controller doesn't maintain VBUS suspend current
 * during a system sleep or is reset when the system wakes up, all the USB
 * power sessions below it will be broken.  This is especially troublesome
 * for mass-storage devices containing mounted filesystems, since the
 * device will appear to have disconnected and all the memory mappings
 * to it will be lost.  Using the USB_PERSIST facility, the device can be
 * made to appear as if it had not disconnected.
 *
3344
 * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
3345
 * every effort to insure that the same device is present after the
3346 3347 3348 3349 3350 3351
 * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
 * quite possible for a device to remain unaltered but its media to be
 * changed.  If the user replaces a flash memory card while the system is
 * asleep, he will have only himself to blame when the filesystem on the
 * new card is corrupted and the system crashes.
 *
A
Alan Stern 已提交
3352 3353
 * Returns 0 on success, else negative errno.
 */
A
Alan Stern 已提交
3354
int usb_port_resume(struct usb_device *udev, pm_message_t msg)
L
Linus Torvalds 已提交
3355
{
3356 3357
	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
	struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
A
Alan Stern 已提交
3358 3359 3360
	int		port1 = udev->portnum;
	int		status;
	u16		portchange, portstatus;
3361

3362
	if (!test_and_set_bit(port1, hub->child_usage_bits)) {
3363 3364 3365 3366 3367 3368 3369 3370
		status = pm_runtime_get_sync(&port_dev->dev);
		if (status < 0) {
			dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
					status);
			return status;
		}
	}

D
Dan Williams 已提交
3371 3372
	usb_lock_port(port_dev);

3373 3374
	/* Skip the initial Clear-Suspend step for a remote wakeup */
	status = hub_port_status(hub, port1, &portstatus, &portchange);
3375
	if (status == 0 && !port_is_suspended(hub, portstatus))
3376
		goto SuspendCleared;
L
Linus Torvalds 已提交
3377 3378

	/* see 7.1.7.7; affects power usage, but not budgeting */
3379
	if (hub_is_superspeed(hub->hdev))
3380
		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
3381
	else
3382
		status = usb_clear_port_feature(hub->hdev,
3383
				port1, USB_PORT_FEAT_SUSPEND);
L
Linus Torvalds 已提交
3384
	if (status) {
3385
		dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
L
Linus Torvalds 已提交
3386 3387
	} else {
		/* drive resume for at least 20 msec */
3388
		dev_dbg(&udev->dev, "usb %sresume\n",
3389
				(PMSG_IS_AUTO(msg) ? "auto-" : ""));
L
Linus Torvalds 已提交
3390 3391 3392 3393 3394 3395
		msleep(25);

		/* Virtual root hubs can trigger on GET_PORT_STATUS to
		 * stop resume signaling.  Then finish the resume
		 * sequence.
		 */
3396
		status = hub_port_status(hub, port1, &portstatus, &portchange);
3397

3398 3399 3400 3401
		/* TRSMRCY = 10 msec */
		msleep(10);
	}

3402
 SuspendCleared:
3403
	if (status == 0) {
A
Alan Stern 已提交
3404
		udev->port_is_suspended = 0;
3405 3406
		if (hub_is_superspeed(hub->hdev)) {
			if (portchange & USB_PORT_STAT_C_LINK_STATE)
3407
				usb_clear_port_feature(hub->hdev, port1,
3408 3409 3410
					USB_PORT_FEAT_C_PORT_LINK_STATE);
		} else {
			if (portchange & USB_PORT_STAT_C_SUSPEND)
3411
				usb_clear_port_feature(hub->hdev, port1,
3412 3413
						USB_PORT_FEAT_C_SUSPEND);
		}
L
Linus Torvalds 已提交
3414 3415
	}

3416 3417 3418 3419
	if (udev->persist_enabled && hub_is_superspeed(hub->hdev))
		status = wait_for_ss_port_enable(udev, hub, &port1, &portchange,
				&portstatus);

3420 3421
	status = check_port_resume_type(udev,
			hub, port1, status, portchange, portstatus);
3422 3423 3424 3425 3426
	if (status == 0)
		status = finish_port_resume(udev);
	if (status < 0) {
		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
		hub_port_logical_disconnect(hub, port1);
A
Andiry Xu 已提交
3427 3428 3429 3430
	} else  {
		/* Try to enable USB2 hardware LPM */
		if (udev->usb2_hw_lpm_capable == 1)
			usb_set_usb2_hardware_lpm(udev, 1);
3431

3432 3433
		/* Try to enable USB3 LTM and LPM */
		usb_enable_ltm(udev);
3434
		usb_unlocked_enable_lpm(udev);
3435
	}
A
Andiry Xu 已提交
3436

D
Dan Williams 已提交
3437 3438
	usb_unlock_port(port_dev);

L
Linus Torvalds 已提交
3439 3440 3441
	return status;
}

3442 3443
#ifdef	CONFIG_PM_RUNTIME

3444
int usb_remote_wakeup(struct usb_device *udev)
L
Linus Torvalds 已提交
3445 3446 3447
{
	int	status = 0;

D
Dan Williams 已提交
3448
	usb_lock_device(udev);
L
Linus Torvalds 已提交
3449
	if (udev->state == USB_STATE_SUSPENDED) {
3450
		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
3451 3452 3453 3454 3455
		status = usb_autoresume_device(udev);
		if (status == 0) {
			/* Let the drivers do their thing, then... */
			usb_autosuspend_device(udev);
		}
L
Linus Torvalds 已提交
3456
	}
D
Dan Williams 已提交
3457
	usb_unlock_device(udev);
L
Linus Torvalds 已提交
3458 3459 3460
	return status;
}

3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479 3480 3481 3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509
/* Returns 1 if there was a remote wakeup and a connect status change. */
static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
		u16 portstatus, u16 portchange)
		__must_hold(&port_dev->status_lock)
{
	struct usb_port *port_dev = hub->ports[port - 1];
	struct usb_device *hdev;
	struct usb_device *udev;
	int connect_change = 0;
	int ret;

	hdev = hub->hdev;
	udev = port_dev->child;
	if (!hub_is_superspeed(hdev)) {
		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
			return 0;
		usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
	} else {
		if (!udev || udev->state != USB_STATE_SUSPENDED ||
				 (portstatus & USB_PORT_STAT_LINK_STATE) !=
				 USB_SS_PORT_LS_U0)
			return 0;
	}

	if (udev) {
		/* TRSMRCY = 10 msec */
		msleep(10);

		usb_unlock_port(port_dev);
		ret = usb_remote_wakeup(udev);
		usb_lock_port(port_dev);
		if (ret < 0)
			connect_change = 1;
	} else {
		ret = -ENODEV;
		hub_port_disable(hub, port, 1);
	}
	dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
	return connect_change;
}

#else

static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
		u16 portstatus, u16 portchange)
{
	return 0;
}

A
Alan Stern 已提交
3510 3511
#endif

3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523 3524 3525 3526
static int check_ports_changed(struct usb_hub *hub)
{
	int port1;

	for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
		u16 portstatus, portchange;
		int status;

		status = hub_port_status(hub, port1, &portstatus, &portchange);
		if (!status && portchange)
			return 1;
	}
	return 0;
}

D
David Brownell 已提交
3527
static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
L
Linus Torvalds 已提交
3528 3529 3530 3531
{
	struct usb_hub		*hub = usb_get_intfdata (intf);
	struct usb_device	*hdev = hub->hdev;
	unsigned		port1;
3532
	int			status;
L
Linus Torvalds 已提交
3533

3534 3535 3536 3537 3538
	/*
	 * Warn if children aren't already suspended.
	 * Also, add up the number of wakeup-enabled descendants.
	 */
	hub->wakeup_enabled_descendants = 0;
L
Linus Torvalds 已提交
3539
	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3540 3541
		struct usb_port *port_dev = hub->ports[port1 - 1];
		struct usb_device *udev = port_dev->child;
L
Linus Torvalds 已提交
3542

3543
		if (udev && udev->can_submit) {
3544 3545
			dev_warn(&port_dev->dev, "device %s not suspended yet\n",
					dev_name(&udev->dev));
3546
			if (PMSG_IS_AUTO(msg))
3547
				return -EBUSY;
3548
		}
3549 3550 3551
		if (udev)
			hub->wakeup_enabled_descendants +=
					wakeup_enabled_descendants(udev);
L
Linus Torvalds 已提交
3552
	}
3553 3554 3555 3556 3557 3558 3559 3560 3561 3562

	if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
		/* check if there are changes pending on hub ports */
		if (check_ports_changed(hub)) {
			if (PMSG_IS_AUTO(msg))
				return -EBUSY;
			pm_wakeup_event(&hdev->dev, 2000);
		}
	}

3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573
	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
		/* Enable hub to send remote wakeup for all ports. */
		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
			status = set_port_feature(hdev,
					port1 |
					USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
					USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
					USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
					USB_PORT_FEAT_REMOTE_WAKE_MASK);
		}
	}
L
Linus Torvalds 已提交
3574

3575
	dev_dbg(&intf->dev, "%s\n", __func__);
3576

3577
	/* stop khubd and related activity */
3578
	hub_quiesce(hub, HUB_SUSPEND);
3579
	return 0;
L
Linus Torvalds 已提交
3580 3581 3582 3583
}

static int hub_resume(struct usb_interface *intf)
{
3584
	struct usb_hub *hub = usb_get_intfdata(intf);
3585

3586
	dev_dbg(&intf->dev, "%s\n", __func__);
3587
	hub_activate(hub, HUB_RESUME);
L
Linus Torvalds 已提交
3588 3589 3590
	return 0;
}

3591
static int hub_reset_resume(struct usb_interface *intf)
A
Alan Stern 已提交
3592
{
3593
	struct usb_hub *hub = usb_get_intfdata(intf);
A
Alan Stern 已提交
3594

3595
	dev_dbg(&intf->dev, "%s\n", __func__);
3596
	hub_activate(hub, HUB_RESET_RESUME);
A
Alan Stern 已提交
3597 3598 3599
	return 0;
}

3600 3601 3602 3603 3604 3605
/**
 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
 * @rhdev: struct usb_device for the root hub
 *
 * The USB host controller driver calls this function when its root hub
 * is resumed and Vbus power has been interrupted or the controller
3606 3607 3608 3609
 * has been reset.  The routine marks @rhdev as having lost power.
 * When the hub driver is resumed it will take notice and carry out
 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
 * the others will be disconnected.
3610 3611 3612 3613 3614 3615 3616 3617
 */
void usb_root_hub_lost_power(struct usb_device *rhdev)
{
	dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
	rhdev->reset_resume = 1;
}
EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);

3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642
static const char * const usb3_lpm_names[]  = {
	"U0",
	"U1",
	"U2",
	"U3",
};

/*
 * Send a Set SEL control transfer to the device, prior to enabling
 * device-initiated U1 or U2.  This lets the device know the exit latencies from
 * the time the device initiates a U1 or U2 exit, to the time it will receive a
 * packet from the host.
 *
 * This function will fail if the SEL or PEL values for udev are greater than
 * the maximum allowed values for the link state to be enabled.
 */
static int usb_req_set_sel(struct usb_device *udev, enum usb3_link_state state)
{
	struct usb_set_sel_req *sel_values;
	unsigned long long u1_sel;
	unsigned long long u1_pel;
	unsigned long long u2_sel;
	unsigned long long u2_pel;
	int ret;

3643 3644 3645
	if (udev->state != USB_STATE_CONFIGURED)
		return 0;

3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665
	/* Convert SEL and PEL stored in ns to us */
	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
	u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
	u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);

	/*
	 * Make sure that the calculated SEL and PEL values for the link
	 * state we're enabling aren't bigger than the max SEL/PEL
	 * value that will fit in the SET SEL control transfer.
	 * Otherwise the device would get an incorrect idea of the exit
	 * latency for the link state, and could start a device-initiated
	 * U1/U2 when the exit latencies are too high.
	 */
	if ((state == USB3_LPM_U1 &&
				(u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
				 u1_pel > USB3_LPM_MAX_U1_SEL_PEL)) ||
			(state == USB3_LPM_U2 &&
			 (u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
			  u2_pel > USB3_LPM_MAX_U2_SEL_PEL))) {
3666
		dev_dbg(&udev->dev, "Device-initiated %s disabled due to long SEL %llu us or PEL %llu us\n",
3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826 3827
				usb3_lpm_names[state], u1_sel, u1_pel);
		return -EINVAL;
	}

	/*
	 * If we're enabling device-initiated LPM for one link state,
	 * but the other link state has a too high SEL or PEL value,
	 * just set those values to the max in the Set SEL request.
	 */
	if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL)
		u1_sel = USB3_LPM_MAX_U1_SEL_PEL;

	if (u1_pel > USB3_LPM_MAX_U1_SEL_PEL)
		u1_pel = USB3_LPM_MAX_U1_SEL_PEL;

	if (u2_sel > USB3_LPM_MAX_U2_SEL_PEL)
		u2_sel = USB3_LPM_MAX_U2_SEL_PEL;

	if (u2_pel > USB3_LPM_MAX_U2_SEL_PEL)
		u2_pel = USB3_LPM_MAX_U2_SEL_PEL;

	/*
	 * usb_enable_lpm() can be called as part of a failed device reset,
	 * which may be initiated by an error path of a mass storage driver.
	 * Therefore, use GFP_NOIO.
	 */
	sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
	if (!sel_values)
		return -ENOMEM;

	sel_values->u1_sel = u1_sel;
	sel_values->u1_pel = u1_pel;
	sel_values->u2_sel = cpu_to_le16(u2_sel);
	sel_values->u2_pel = cpu_to_le16(u2_pel);

	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
			USB_REQ_SET_SEL,
			USB_RECIP_DEVICE,
			0, 0,
			sel_values, sizeof *(sel_values),
			USB_CTRL_SET_TIMEOUT);
	kfree(sel_values);
	return ret;
}

/*
 * Enable or disable device-initiated U1 or U2 transitions.
 */
static int usb_set_device_initiated_lpm(struct usb_device *udev,
		enum usb3_link_state state, bool enable)
{
	int ret;
	int feature;

	switch (state) {
	case USB3_LPM_U1:
		feature = USB_DEVICE_U1_ENABLE;
		break;
	case USB3_LPM_U2:
		feature = USB_DEVICE_U2_ENABLE;
		break;
	default:
		dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
				__func__, enable ? "enable" : "disable");
		return -EINVAL;
	}

	if (udev->state != USB_STATE_CONFIGURED) {
		dev_dbg(&udev->dev, "%s: Can't %s %s state "
				"for unconfigured device.\n",
				__func__, enable ? "enable" : "disable",
				usb3_lpm_names[state]);
		return 0;
	}

	if (enable) {
		/*
		 * Now send the control transfer to enable device-initiated LPM
		 * for either U1 or U2.
		 */
		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
				USB_REQ_SET_FEATURE,
				USB_RECIP_DEVICE,
				feature,
				0, NULL, 0,
				USB_CTRL_SET_TIMEOUT);
	} else {
		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
				USB_REQ_CLEAR_FEATURE,
				USB_RECIP_DEVICE,
				feature,
				0, NULL, 0,
				USB_CTRL_SET_TIMEOUT);
	}
	if (ret < 0) {
		dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
				enable ? "Enable" : "Disable",
				usb3_lpm_names[state]);
		return -EBUSY;
	}
	return 0;
}

static int usb_set_lpm_timeout(struct usb_device *udev,
		enum usb3_link_state state, int timeout)
{
	int ret;
	int feature;

	switch (state) {
	case USB3_LPM_U1:
		feature = USB_PORT_FEAT_U1_TIMEOUT;
		break;
	case USB3_LPM_U2:
		feature = USB_PORT_FEAT_U2_TIMEOUT;
		break;
	default:
		dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
				__func__);
		return -EINVAL;
	}

	if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
			timeout != USB3_LPM_DEVICE_INITIATED) {
		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
				"which is a reserved value.\n",
				usb3_lpm_names[state], timeout);
		return -EINVAL;
	}

	ret = set_port_feature(udev->parent,
			USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
			feature);
	if (ret < 0) {
		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
				"error code %i\n", usb3_lpm_names[state],
				timeout, ret);
		return -EBUSY;
	}
	if (state == USB3_LPM_U1)
		udev->u1_params.timeout = timeout;
	else
		udev->u2_params.timeout = timeout;
	return 0;
}

/*
 * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
 * U1/U2 entry.
 *
 * We will attempt to enable U1 or U2, but there are no guarantees that the
 * control transfers to set the hub timeout or enable device-initiated U1/U2
 * will be successful.
 *
 * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
 * driver know about it.  If that call fails, it should be harmless, and just
 * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
 */
static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
		enum usb3_link_state state)
{
3828
	int timeout, ret;
3829 3830 3831 3832 3833 3834 3835 3836 3837 3838
	__u8 u1_mel = udev->bos->ss_cap->bU1devExitLat;
	__le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat;

	/* If the device says it doesn't have *any* exit latency to come out of
	 * U1 or U2, it's probably lying.  Assume it doesn't implement that link
	 * state.
	 */
	if ((state == USB3_LPM_U1 && u1_mel == 0) ||
			(state == USB3_LPM_U2 && u2_mel == 0))
		return;
3839

3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850
	/*
	 * First, let the device know about the exit latencies
	 * associated with the link state we're about to enable.
	 */
	ret = usb_req_set_sel(udev, state);
	if (ret < 0) {
		dev_warn(&udev->dev, "Set SEL for device-initiated %s failed.\n",
				usb3_lpm_names[state]);
		return;
	}

3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939
	/* We allow the host controller to set the U1/U2 timeout internally
	 * first, so that it can change its schedule to account for the
	 * additional latency to send data to a device in a lower power
	 * link state.
	 */
	timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);

	/* xHCI host controller doesn't want to enable this LPM state. */
	if (timeout == 0)
		return;

	if (timeout < 0) {
		dev_warn(&udev->dev, "Could not enable %s link state, "
				"xHCI error %i.\n", usb3_lpm_names[state],
				timeout);
		return;
	}

	if (usb_set_lpm_timeout(udev, state, timeout))
		/* If we can't set the parent hub U1/U2 timeout,
		 * device-initiated LPM won't be allowed either, so let the xHCI
		 * host know that this link state won't be enabled.
		 */
		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);

	/* Only a configured device will accept the Set Feature U1/U2_ENABLE */
	else if (udev->actconfig)
		usb_set_device_initiated_lpm(udev, state, true);

}

/*
 * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
 * U1/U2 entry.
 *
 * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
 * If zero is returned, the parent will not allow the link to go into U1/U2.
 *
 * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
 * it won't have an effect on the bus link state because the parent hub will
 * still disallow device-initiated U1/U2 entry.
 *
 * If zero is returned, the xHCI host controller may still think U1/U2 entry is
 * possible.  The result will be slightly more bus bandwidth will be taken up
 * (to account for U1/U2 exit latency), but it should be harmless.
 */
static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
		enum usb3_link_state state)
{
	int feature;

	switch (state) {
	case USB3_LPM_U1:
		feature = USB_PORT_FEAT_U1_TIMEOUT;
		break;
	case USB3_LPM_U2:
		feature = USB_PORT_FEAT_U2_TIMEOUT;
		break;
	default:
		dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
				__func__);
		return -EINVAL;
	}

	if (usb_set_lpm_timeout(udev, state, 0))
		return -EBUSY;

	usb_set_device_initiated_lpm(udev, state, false);

	if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
				"bus schedule bandwidth may be impacted.\n",
				usb3_lpm_names[state]);
	return 0;
}

/*
 * Disable hub-initiated and device-initiated U1 and U2 entry.
 * Caller must own the bandwidth_mutex.
 *
 * This will call usb_enable_lpm() on failure, which will decrement
 * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
 */
int usb_disable_lpm(struct usb_device *udev)
{
	struct usb_hcd *hcd;

	if (!udev || !udev->parent ||
			udev->speed != USB_SPEED_SUPER ||
3940 3941
			!udev->lpm_capable ||
			udev->state < USB_STATE_DEFAULT)
3942 3943 3944 3945 3946 3947 3948
		return 0;

	hcd = bus_to_hcd(udev->bus);
	if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
		return 0;

	udev->lpm_disable_count++;
3949
	if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
3950 3951 3952 3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984 3985 3986 3987 3988 3989 3990 3991 3992 3993 3994 3995 3996
		return 0;

	/* If LPM is enabled, attempt to disable it. */
	if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
		goto enable_lpm;
	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
		goto enable_lpm;

	return 0;

enable_lpm:
	usb_enable_lpm(udev);
	return -EBUSY;
}
EXPORT_SYMBOL_GPL(usb_disable_lpm);

/* Grab the bandwidth_mutex before calling usb_disable_lpm() */
int usb_unlocked_disable_lpm(struct usb_device *udev)
{
	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
	int ret;

	if (!hcd)
		return -EINVAL;

	mutex_lock(hcd->bandwidth_mutex);
	ret = usb_disable_lpm(udev);
	mutex_unlock(hcd->bandwidth_mutex);

	return ret;
}
EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);

/*
 * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
 * xHCI host policy may prevent U1 or U2 from being enabled.
 *
 * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
 * until the lpm_disable_count drops to zero.  Caller must own the
 * bandwidth_mutex.
 */
void usb_enable_lpm(struct usb_device *udev)
{
	struct usb_hcd *hcd;

	if (!udev || !udev->parent ||
			udev->speed != USB_SPEED_SUPER ||
3997 3998
			!udev->lpm_capable ||
			udev->state < USB_STATE_DEFAULT)
3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031 4032
		return;

	udev->lpm_disable_count--;
	hcd = bus_to_hcd(udev->bus);
	/* Double check that we can both enable and disable LPM.
	 * Device must be configured to accept set feature U1/U2 timeout.
	 */
	if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
			!hcd->driver->disable_usb3_lpm_timeout)
		return;

	if (udev->lpm_disable_count > 0)
		return;

	usb_enable_link_state(hcd, udev, USB3_LPM_U1);
	usb_enable_link_state(hcd, udev, USB3_LPM_U2);
}
EXPORT_SYMBOL_GPL(usb_enable_lpm);

/* Grab the bandwidth_mutex before calling usb_enable_lpm() */
void usb_unlocked_enable_lpm(struct usb_device *udev)
{
	struct usb_hcd *hcd = bus_to_hcd(udev->bus);

	if (!hcd)
		return;

	mutex_lock(hcd->bandwidth_mutex);
	usb_enable_lpm(udev);
	mutex_unlock(hcd->bandwidth_mutex);
}
EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);


A
Alan Stern 已提交
4033 4034
#else	/* CONFIG_PM */

A
Alan Stern 已提交
4035 4036 4037
#define hub_suspend		NULL
#define hub_resume		NULL
#define hub_reset_resume	NULL
4038 4039 4040 4041 4042

int usb_disable_lpm(struct usb_device *udev)
{
	return 0;
}
4043
EXPORT_SYMBOL_GPL(usb_disable_lpm);
4044 4045

void usb_enable_lpm(struct usb_device *udev) { }
4046
EXPORT_SYMBOL_GPL(usb_enable_lpm);
4047 4048 4049 4050 4051

int usb_unlocked_disable_lpm(struct usb_device *udev)
{
	return 0;
}
4052
EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4053 4054

void usb_unlocked_enable_lpm(struct usb_device *udev) { }
4055
EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4056 4057 4058 4059 4060 4061 4062 4063 4064

int usb_disable_ltm(struct usb_device *udev)
{
	return 0;
}
EXPORT_SYMBOL_GPL(usb_disable_ltm);

void usb_enable_ltm(struct usb_device *udev) { }
EXPORT_SYMBOL_GPL(usb_enable_ltm);
A
Alan Stern 已提交
4065

4066 4067 4068 4069 4070 4071
static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
		u16 portstatus, u16 portchange)
{
	return 0;
}

A
Alan Stern 已提交
4072
#endif	/* CONFIG_PM */
A
Alan Stern 已提交
4073

L
Linus Torvalds 已提交
4074 4075 4076 4077 4078 4079

/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
 *
 * Between connect detection and reset signaling there must be a delay
 * of 100ms at least for debounce and power-settling.  The corresponding
 * timer shall restart whenever the downstream port detects a disconnect.
4080
 *
L
Linus Torvalds 已提交
4081 4082 4083 4084 4085 4086 4087 4088 4089
 * Apparently there are some bluetooth and irda-dongles and a number of
 * low-speed devices for which this debounce period may last over a second.
 * Not covered by the spec - but easy to deal with.
 *
 * This implementation uses a 1500ms total debounce timeout; if the
 * connection isn't stable by then it returns -ETIMEDOUT.  It checks
 * every 25ms for transient disconnects.  When the port status has been
 * unchanged for 100ms it returns the port status.
 */
4090
int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
L
Linus Torvalds 已提交
4091 4092 4093 4094
{
	int ret;
	u16 portchange, portstatus;
	unsigned connection = 0xffff;
4095 4096
	int total_time, stable_time = 0;
	struct usb_port *port_dev = hub->ports[port1 - 1];
L
Linus Torvalds 已提交
4097 4098 4099 4100 4101 4102 4103 4104

	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
		ret = hub_port_status(hub, port1, &portstatus, &portchange);
		if (ret < 0)
			return ret;

		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
4105 4106 4107
			if (!must_be_connected ||
			     (connection == USB_PORT_STAT_CONNECTION))
				stable_time += HUB_DEBOUNCE_STEP;
L
Linus Torvalds 已提交
4108 4109 4110 4111 4112 4113 4114 4115
			if (stable_time >= HUB_DEBOUNCE_STABLE)
				break;
		} else {
			stable_time = 0;
			connection = portstatus & USB_PORT_STAT_CONNECTION;
		}

		if (portchange & USB_PORT_STAT_C_CONNECTION) {
4116
			usb_clear_port_feature(hub->hdev, port1,
L
Linus Torvalds 已提交
4117 4118 4119 4120 4121 4122 4123 4124
					USB_PORT_FEAT_C_CONNECTION);
		}

		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
			break;
		msleep(HUB_DEBOUNCE_STEP);
	}

4125 4126
	dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
			total_time, stable_time, portstatus);
L
Linus Torvalds 已提交
4127 4128 4129 4130 4131 4132

	if (stable_time < HUB_DEBOUNCE_STABLE)
		return -ETIMEDOUT;
	return portstatus;
}

4133
void usb_ep0_reinit(struct usb_device *udev)
L
Linus Torvalds 已提交
4134
{
4135 4136
	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
4137
	usb_enable_endpoint(udev, &udev->ep0, true);
L
Linus Torvalds 已提交
4138
}
4139
EXPORT_SYMBOL_GPL(usb_ep0_reinit);
L
Linus Torvalds 已提交
4140 4141 4142 4143

#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
#define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)

4144
static int hub_set_address(struct usb_device *udev, int devnum)
L
Linus Torvalds 已提交
4145 4146
{
	int retval;
4147
	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
L
Linus Torvalds 已提交
4148

4149 4150 4151 4152 4153
	/*
	 * The host controller will choose the device address,
	 * instead of the core having chosen it earlier
	 */
	if (!hcd->driver->address_device && devnum <= 1)
L
Linus Torvalds 已提交
4154 4155 4156 4157 4158
		return -EINVAL;
	if (udev->state == USB_STATE_ADDRESS)
		return 0;
	if (udev->state != USB_STATE_DEFAULT)
		return -EINVAL;
4159
	if (hcd->driver->address_device)
4160
		retval = hcd->driver->address_device(hcd, udev);
4161
	else
4162 4163 4164
		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
				USB_REQ_SET_ADDRESS, 0, devnum, 0,
				NULL, 0, USB_CTRL_SET_TIMEOUT);
L
Linus Torvalds 已提交
4165
	if (retval == 0) {
4166
		update_devnum(udev, devnum);
4167
		/* Device now using proper address. */
L
Linus Torvalds 已提交
4168
		usb_set_device_state(udev, USB_STATE_ADDRESS);
4169
		usb_ep0_reinit(udev);
L
Linus Torvalds 已提交
4170 4171 4172 4173
	}
	return retval;
}

4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184
/*
 * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
 * when they're plugged into a USB 2.0 port, but they don't work when LPM is
 * enabled.
 *
 * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
 * device says it supports the new USB 2.0 Link PM errata by setting the BESL
 * support bit in the BOS descriptor.
 */
static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
{
4185 4186
	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
	int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
4187 4188 4189 4190

	if (!udev->usb2_hw_lpm_capable)
		return;

4191 4192
	if (hub)
		connect_type = hub->ports[udev->portnum - 1]->connect_type;
4193

4194
	if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
4195 4196 4197 4198 4199 4200
			connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
		udev->usb2_hw_lpm_allowed = 1;
		usb_set_usb2_hardware_lpm(udev, 1);
	}
}

4201 4202 4203 4204 4205 4206 4207 4208 4209 4210 4211 4212 4213 4214
static int hub_enable_device(struct usb_device *udev)
{
	struct usb_hcd *hcd = bus_to_hcd(udev->bus);

	if (!hcd->driver->enable_device)
		return 0;
	if (udev->state == USB_STATE_ADDRESS)
		return 0;
	if (udev->state != USB_STATE_DEFAULT)
		return -EINVAL;

	return hcd->driver->enable_device(hcd, udev);
}

L
Linus Torvalds 已提交
4215 4216 4217 4218 4219
/* Reset device, (re)assign address, get device descriptor.
 * Device connection must be stable, no more debouncing needed.
 * Returns device in USB_STATE_ADDRESS, except on error.
 *
 * If this is called for an already-existing device (as part of
D
Dan Williams 已提交
4220 4221 4222 4223
 * usb_reset_and_verify_device), the caller must own the device lock and
 * the port lock.  For a newly detected device that is not accessible
 * through any global pointers, it's not necessary to lock the device,
 * but it is still necessary to lock the port.
L
Linus Torvalds 已提交
4224 4225 4226 4227 4228 4229
 */
static int
hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
		int retry_counter)
{
	struct usb_device	*hdev = hub->hdev;
4230
	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
L
Linus Torvalds 已提交
4231 4232 4233
	int			i, j, retval;
	unsigned		delay = HUB_SHORT_RESET_TIME;
	enum usb_device_speed	oldspeed = udev->speed;
4234
	const char		*speed;
4235
	int			devnum = udev->devnum;
L
Linus Torvalds 已提交
4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246 4247 4248 4249 4250

	/* root hub ports have a slightly longer reset period
	 * (from USB 2.0 spec, section 7.1.7.5)
	 */
	if (!hdev->parent) {
		delay = HUB_ROOT_RESET_TIME;
		if (port1 == hdev->bus->otg_port)
			hdev->bus->b_hnp_enable = 0;
	}

	/* Some low speed devices have problems with the quick delay, so */
	/*  be a bit pessimistic with those devices. RHbug #23670 */
	if (oldspeed == USB_SPEED_LOW)
		delay = HUB_LONG_RESET_TIME;

4251
	mutex_lock(&hdev->bus->usb_address0_mutex);
L
Linus Torvalds 已提交
4252

4253 4254
	/* Reset the device; full speed may morph to high speed */
	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
A
Andiry Xu 已提交
4255
	retval = hub_port_reset(hub, port1, udev, delay, false);
4256 4257 4258 4259
	if (retval < 0)		/* error or disconnect */
		goto fail;
	/* success, speed is known */

L
Linus Torvalds 已提交
4260 4261 4262 4263 4264 4265 4266
	retval = -ENODEV;

	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
		dev_dbg(&udev->dev, "device reset changed speed!\n");
		goto fail;
	}
	oldspeed = udev->speed;
4267

L
Linus Torvalds 已提交
4268 4269
	/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
	 * it's fixed size except for full speed devices.
4270 4271
	 * For Wireless USB devices, ep0 max packet is always 512 (tho
	 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
L
Linus Torvalds 已提交
4272 4273
	 */
	switch (udev->speed) {
4274
	case USB_SPEED_SUPER:
4275
	case USB_SPEED_WIRELESS:	/* fixed at 512 */
4276
		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
4277
		break;
L
Linus Torvalds 已提交
4278
	case USB_SPEED_HIGH:		/* fixed at 64 */
4279
		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
L
Linus Torvalds 已提交
4280 4281 4282 4283 4284 4285
		break;
	case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
		/* to determine the ep0 maxpacket size, try to read
		 * the device descriptor to get bMaxPacketSize0 and
		 * then correct our initial guess.
		 */
4286
		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
L
Linus Torvalds 已提交
4287 4288
		break;
	case USB_SPEED_LOW:		/* fixed at 8 */
4289
		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
L
Linus Torvalds 已提交
4290 4291 4292 4293
		break;
	default:
		goto fail;
	}
4294 4295 4296 4297 4298 4299

	if (udev->speed == USB_SPEED_WIRELESS)
		speed = "variable speed Wireless";
	else
		speed = usb_speed_string(udev->speed);

4300 4301
	if (udev->speed != USB_SPEED_SUPER)
		dev_info(&udev->dev,
4302 4303
				"%s %s USB device number %d using %s\n",
				(udev->config) ? "reset" : "new", speed,
4304
				devnum, udev->bus->controller->driver->name);
L
Linus Torvalds 已提交
4305 4306 4307 4308 4309 4310 4311

	/* Set up TT records, if needed  */
	if (hdev->tt) {
		udev->tt = hdev->tt;
		udev->ttport = hdev->ttport;
	} else if (udev->speed != USB_SPEED_HIGH
			&& hdev->speed == USB_SPEED_HIGH) {
4312 4313 4314 4315 4316
		if (!hub->tt.hub) {
			dev_err(&udev->dev, "parent hub has no TT\n");
			retval = -EINVAL;
			goto fail;
		}
L
Linus Torvalds 已提交
4317 4318 4319
		udev->tt = &hub->tt;
		udev->ttport = port1;
	}
4320

L
Linus Torvalds 已提交
4321 4322 4323 4324 4325
	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
	 * Because device hardware and firmware is sometimes buggy in
	 * this area, and this is how Linux has done it for ages.
	 * Change it cautiously.
	 *
4326
	 * NOTE:  If use_new_scheme() is true we will start by issuing
L
Linus Torvalds 已提交
4327 4328 4329 4330 4331 4332 4333
	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
	 * so it may help with some non-standards-compliant devices.
	 * Otherwise we start with SET_ADDRESS and then try to read the
	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
	 * value.
	 */
	for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
4334 4335 4336
		bool did_new_scheme = false;

		if (use_new_scheme(udev, retry_counter)) {
L
Linus Torvalds 已提交
4337 4338 4339
			struct usb_device_descriptor *buf;
			int r = 0;

4340 4341
			did_new_scheme = true;
			retval = hub_enable_device(udev);
4342 4343 4344 4345
			if (retval < 0) {
				dev_err(&udev->dev,
					"hub failed to enable device, error %d\n",
					retval);
4346
				goto fail;
4347
			}
4348

L
Linus Torvalds 已提交
4349 4350 4351 4352 4353 4354 4355
#define GET_DESCRIPTOR_BUFSIZE	64
			buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
			if (!buf) {
				retval = -ENOMEM;
				continue;
			}

4356 4357 4358
			/* Retry on all errors; some devices are flakey.
			 * 255 is for WUSB devices, we actually need to use
			 * 512 (WUSB1.0[4.8.1]).
L
Linus Torvalds 已提交
4359 4360 4361 4362 4363 4364 4365
			 */
			for (j = 0; j < 3; ++j) {
				buf->bMaxPacketSize0 = 0;
				r = usb_control_msg(udev, usb_rcvaddr0pipe(),
					USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
					USB_DT_DEVICE << 8, 0,
					buf, GET_DESCRIPTOR_BUFSIZE,
4366
					initial_descriptor_timeout);
L
Linus Torvalds 已提交
4367
				switch (buf->bMaxPacketSize0) {
4368
				case 8: case 16: case 32: case 64: case 255:
L
Linus Torvalds 已提交
4369 4370 4371 4372 4373 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386
					if (buf->bDescriptorType ==
							USB_DT_DEVICE) {
						r = 0;
						break;
					}
					/* FALL THROUGH */
				default:
					if (r == 0)
						r = -EPROTO;
					break;
				}
				if (r == 0)
					break;
			}
			udev->descriptor.bMaxPacketSize0 =
					buf->bMaxPacketSize0;
			kfree(buf);

A
Andiry Xu 已提交
4387
			retval = hub_port_reset(hub, port1, udev, delay, false);
L
Linus Torvalds 已提交
4388 4389 4390 4391 4392 4393 4394 4395 4396
			if (retval < 0)		/* error or disconnect */
				goto fail;
			if (oldspeed != udev->speed) {
				dev_dbg(&udev->dev,
					"device reset changed speed!\n");
				retval = -ENODEV;
				goto fail;
			}
			if (r) {
4397 4398 4399
				if (r != -ENODEV)
					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
							r);
L
Linus Torvalds 已提交
4400 4401 4402 4403 4404 4405
				retval = -EMSGSIZE;
				continue;
			}
#undef GET_DESCRIPTOR_BUFSIZE
		}

4406 4407 4408 4409 4410
		/*
		 * If device is WUSB, we already assigned an
		 * unauthorized address in the Connect Ack sequence;
		 * authorization will assign the final address.
		 */
4411
		if (udev->wusb == 0) {
4412 4413 4414 4415 4416 4417 4418
			for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
				retval = hub_set_address(udev, devnum);
				if (retval >= 0)
					break;
				msleep(200);
			}
			if (retval < 0) {
4419 4420 4421
				if (retval != -ENODEV)
					dev_err(&udev->dev, "device not accepting address %d, error %d\n",
							devnum, retval);
4422 4423
				goto fail;
			}
4424 4425 4426
			if (udev->speed == USB_SPEED_SUPER) {
				devnum = udev->devnum;
				dev_info(&udev->dev,
4427
						"%s SuperSpeed USB device number %d using %s\n",
4428
						(udev->config) ? "reset" : "new",
4429
						devnum, udev->bus->controller->driver->name);
4430
			}
4431 4432 4433 4434 4435 4436

			/* cope with hardware quirkiness:
			 *  - let SET_ADDRESS settle, some device hardware wants it
			 *  - read ep0 maxpacket even for high and low speed,
			 */
			msleep(10);
4437 4438 4439 4440 4441
			/* use_new_scheme() checks the speed which may have
			 * changed since the initial look so we cache the result
			 * in did_new_scheme
			 */
			if (did_new_scheme)
L
Linus Torvalds 已提交
4442
				break;
4443
		}
L
Linus Torvalds 已提交
4444 4445 4446

		retval = usb_get_device_descriptor(udev, 8);
		if (retval < 8) {
4447 4448
			if (retval != -ENODEV)
				dev_err(&udev->dev,
4449 4450
					"device descriptor read/8, error %d\n",
					retval);
L
Linus Torvalds 已提交
4451 4452 4453 4454 4455 4456 4457 4458 4459 4460
			if (retval >= 0)
				retval = -EMSGSIZE;
		} else {
			retval = 0;
			break;
		}
	}
	if (retval)
		goto fail;

4461
	if (hcd->phy && !hdev->parent)
4462
		usb_phy_notify_connect(hcd->phy, udev->speed);
4463

4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474 4475 4476 4477 4478 4479
	/*
	 * Some superspeed devices have finished the link training process
	 * and attached to a superspeed hub port, but the device descriptor
	 * got from those devices show they aren't superspeed devices. Warm
	 * reset the port attached by the devices can fix them.
	 */
	if ((udev->speed == USB_SPEED_SUPER) &&
			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
		dev_err(&udev->dev, "got a wrong device descriptor, "
				"warm reset device\n");
		hub_port_reset(hub, port1, udev,
				HUB_BH_RESET_TIME, true);
		retval = -EINVAL;
		goto fail;
	}

4480 4481 4482 4483 4484
	if (udev->descriptor.bMaxPacketSize0 == 0xff ||
			udev->speed == USB_SPEED_SUPER)
		i = 512;
	else
		i = udev->descriptor.bMaxPacketSize0;
4485
	if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
4486
		if (udev->speed == USB_SPEED_LOW ||
L
Linus Torvalds 已提交
4487
				!(i == 8 || i == 16 || i == 32 || i == 64)) {
4488
			dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
L
Linus Torvalds 已提交
4489 4490 4491
			retval = -EMSGSIZE;
			goto fail;
		}
4492 4493 4494 4495
		if (udev->speed == USB_SPEED_FULL)
			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
		else
			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
L
Linus Torvalds 已提交
4496
		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
4497
		usb_ep0_reinit(udev);
L
Linus Torvalds 已提交
4498
	}
4499

L
Linus Torvalds 已提交
4500 4501
	retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
	if (retval < (signed)sizeof(udev->descriptor)) {
4502 4503 4504
		if (retval != -ENODEV)
			dev_err(&udev->dev, "device descriptor read/all, error %d\n",
					retval);
L
Linus Torvalds 已提交
4505 4506 4507 4508 4509
		if (retval >= 0)
			retval = -ENOMSG;
		goto fail;
	}

4510 4511
	if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
		retval = usb_get_bos_descriptor(udev);
4512
		if (!retval) {
4513
			udev->lpm_capable = usb_device_supports_lpm(udev);
4514 4515
			usb_set_lpm_parameters(udev);
		}
4516
	}
A
Andiry Xu 已提交
4517

L
Linus Torvalds 已提交
4518
	retval = 0;
4519 4520 4521
	/* notify HCD that we have a device connected and addressed */
	if (hcd->driver->update_device)
		hcd->driver->update_device(hcd, udev);
4522
	hub_set_initial_usb2_lpm_policy(udev);
L
Linus Torvalds 已提交
4523
fail:
4524
	if (retval) {
L
Linus Torvalds 已提交
4525
		hub_port_disable(hub, port1, 0);
4526
		update_devnum(udev, devnum);	/* for disconnect processing */
4527
	}
4528
	mutex_unlock(&hdev->bus->usb_address0_mutex);
L
Linus Torvalds 已提交
4529 4530 4531 4532 4533 4534 4535 4536 4537
	return retval;
}

static void
check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
{
	struct usb_qualifier_descriptor	*qual;
	int				status;

4538 4539 4540
	if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
		return;

4541
	qual = kmalloc (sizeof *qual, GFP_KERNEL);
L
Linus Torvalds 已提交
4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552
	if (qual == NULL)
		return;

	status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
			qual, sizeof *qual);
	if (status == sizeof *qual) {
		dev_info(&udev->dev, "not running at top speed; "
			"connect to a high speed hub\n");
		/* hub LEDs are probably harder to miss than syslog */
		if (hub->has_indicators) {
			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
4553 4554
			queue_delayed_work(system_power_efficient_wq,
					&hub->leds, 0);
L
Linus Torvalds 已提交
4555 4556
		}
	}
4557
	kfree(qual);
L
Linus Torvalds 已提交
4558 4559 4560 4561 4562 4563 4564
}

static unsigned
hub_power_remaining (struct usb_hub *hub)
{
	struct usb_device *hdev = hub->hdev;
	int remaining;
4565
	int port1;
L
Linus Torvalds 已提交
4566

4567
	if (!hub->limited_power)
L
Linus Torvalds 已提交
4568 4569
		return 0;

4570 4571
	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
4572 4573 4574 4575
		struct usb_port *port_dev = hub->ports[port1 - 1];
		struct usb_device *udev = port_dev->child;
		unsigned unit_load;
		int delta;
L
Linus Torvalds 已提交
4576 4577 4578

		if (!udev)
			continue;
4579 4580 4581 4582
		if (hub_is_superspeed(udev))
			unit_load = 150;
		else
			unit_load = 100;
L
Linus Torvalds 已提交
4583

4584 4585 4586 4587
		/*
		 * Unconfigured devices may not use more than one unit load,
		 * or 8mA for OTG ports
		 */
L
Linus Torvalds 已提交
4588
		if (udev->actconfig)
4589
			delta = usb_get_max_power(udev, udev->actconfig);
4590
		else if (port1 != udev->bus->otg_port || hdev->parent)
4591
			delta = unit_load;
L
Linus Torvalds 已提交
4592
		else
4593 4594
			delta = 8;
		if (delta > hub->mA_per_port)
4595 4596
			dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
					delta, hub->mA_per_port);
L
Linus Torvalds 已提交
4597 4598 4599
		remaining -= delta;
	}
	if (remaining < 0) {
4600
		dev_warn(hub->intfdev, "%dmA over power budget!\n",
4601
			-remaining);
L
Linus Torvalds 已提交
4602 4603 4604 4605 4606
		remaining = 0;
	}
	return remaining;
}

4607 4608
static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
		u16 portchange)
L
Linus Torvalds 已提交
4609 4610
{
	int status, i;
4611
	unsigned unit_load;
L
Linus Torvalds 已提交
4612
	struct usb_device *hdev = hub->hdev;
4613
	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
4614
	struct usb_port *port_dev = hub->ports[port1 - 1];
4615
	struct usb_device *udev = port_dev->child;
4616
	static int unreliable_port = -1;
4617

A
Alan Stern 已提交
4618
	/* Disconnect any existing devices under this port */
4619 4620 4621
	if (udev) {
		if (hcd->phy && !hdev->parent &&
				!(portstatus & USB_PORT_STAT_CONNECTION))
4622
			usb_phy_notify_disconnect(hcd->phy, udev->speed);
4623
		usb_disconnect(&port_dev->child);
4624
	}
A
Alan Stern 已提交
4625

4626 4627 4628 4629 4630 4631 4632
	/* We can forget about a "removed" device when there's a physical
	 * disconnect or the connect status changes.
	 */
	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
			(portchange & USB_PORT_STAT_C_CONNECTION))
		clear_bit(port1, hub->removed_bits);

4633 4634
	if (portchange & (USB_PORT_STAT_C_CONNECTION |
				USB_PORT_STAT_C_ENABLE)) {
4635
		status = hub_port_debounce_be_stable(hub, port1);
4636
		if (status < 0) {
4637 4638 4639
			if (status != -ENODEV &&
				port1 != unreliable_port &&
				printk_ratelimit())
4640
				dev_err(&port_dev->dev, "connect-debounce failed\n");
4641
			portstatus &= ~USB_PORT_STAT_CONNECTION;
4642
			unreliable_port = port1;
4643 4644 4645 4646 4647
		} else {
			portstatus = status;
		}
	}

4648 4649 4650 4651 4652
	/* Return now if debouncing failed or nothing is connected or
	 * the device was "removed".
	 */
	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
			test_bit(port1, hub->removed_bits)) {
L
Linus Torvalds 已提交
4653 4654

		/* maybe switch power back on (e.g. root hub was reset) */
4655
		if (hub_is_port_power_switchable(hub)
4656
				&& !port_is_power_on(hub, portstatus))
L
Linus Torvalds 已提交
4657
			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
4658

L
Linus Torvalds 已提交
4659
		if (portstatus & USB_PORT_STAT_ENABLE)
4660
			goto done;
L
Linus Torvalds 已提交
4661 4662
		return;
	}
4663 4664 4665 4666
	if (hub_is_superspeed(hub->hdev))
		unit_load = 150;
	else
		unit_load = 100;
L
Linus Torvalds 已提交
4667

4668
	status = 0;
L
Linus Torvalds 已提交
4669 4670 4671 4672 4673 4674 4675
	for (i = 0; i < SET_CONFIG_TRIES; i++) {

		/* reallocate for each attempt, since references
		 * to the previous one can escape in various ways
		 */
		udev = usb_alloc_dev(hdev, hdev->bus, port1);
		if (!udev) {
4676 4677
			dev_err(&port_dev->dev,
					"couldn't allocate usb_device\n");
L
Linus Torvalds 已提交
4678 4679 4680 4681
			goto done;
		}

		usb_set_device_state(udev, USB_STATE_POWERED);
4682
		udev->bus_mA = hub->mA_per_port;
4683
		udev->level = hdev->level + 1;
4684
		udev->wusb = hub_is_wusb(hub);
4685

4686 4687
		/* Only USB 3.0 devices are connected to SuperSpeed hubs. */
		if (hub_is_superspeed(hub->hdev))
4688 4689 4690 4691
			udev->speed = USB_SPEED_SUPER;
		else
			udev->speed = USB_SPEED_UNKNOWN;

4692
		choose_devnum(udev);
4693 4694 4695
		if (udev->devnum <= 0) {
			status = -ENOTCONN;	/* Don't retry */
			goto loop;
4696 4697
		}

4698
		/* reset (non-USB 3.0 devices) and get descriptor */
D
Dan Williams 已提交
4699
		usb_lock_port(port_dev);
L
Linus Torvalds 已提交
4700
		status = hub_port_init(hub, udev, port1, i);
D
Dan Williams 已提交
4701
		usb_unlock_port(port_dev);
L
Linus Torvalds 已提交
4702 4703 4704
		if (status < 0)
			goto loop;

4705 4706 4707 4708
		usb_detect_quirks(udev);
		if (udev->quirks & USB_QUIRK_DELAY_INIT)
			msleep(1000);

L
Linus Torvalds 已提交
4709 4710 4711 4712 4713 4714 4715
		/* consecutive bus-powered hubs aren't reliable; they can
		 * violate the voltage drop budget.  if the new child has
		 * a "powered" LED, users should notice we didn't enable it
		 * (without reading syslog), even without per-port LEDs
		 * on the parent.
		 */
		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
4716
				&& udev->bus_mA <= unit_load) {
L
Linus Torvalds 已提交
4717 4718 4719 4720
			u16	devstat;

			status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
					&devstat);
4721
			if (status) {
L
Linus Torvalds 已提交
4722 4723 4724 4725 4726 4727 4728 4729 4730 4731
				dev_dbg(&udev->dev, "get status %d ?\n", status);
				goto loop_disable;
			}
			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
				dev_err(&udev->dev,
					"can't connect bus-powered hub "
					"to this port\n");
				if (hub->has_indicators) {
					hub->indicator[port1-1] =
						INDICATOR_AMBER_BLINK;
4732 4733 4734
					queue_delayed_work(
						system_power_efficient_wq,
						&hub->leds, 0);
L
Linus Torvalds 已提交
4735 4736 4737 4738 4739
				}
				status = -ENOTCONN;	/* Don't retry */
				goto loop_disable;
			}
		}
4740

L
Linus Torvalds 已提交
4741 4742 4743 4744 4745 4746
		/* check for devices running slower than they could */
		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
				&& udev->speed == USB_SPEED_FULL
				&& highspeed_hubs != 0)
			check_highspeed (hub, udev, port1);

4747
		/* Store the parent's children[] pointer.  At this point
L
Linus Torvalds 已提交
4748 4749 4750 4751 4752
		 * udev becomes globally accessible, although presumably
		 * no one will look at it until hdev is unlocked.
		 */
		status = 0;

4753 4754
		mutex_lock(&usb_port_peer_mutex);

L
Linus Torvalds 已提交
4755 4756 4757 4758 4759 4760 4761 4762
		/* We mustn't add new devices if the parent hub has
		 * been disconnected; we would race with the
		 * recursively_mark_NOTATTACHED() routine.
		 */
		spin_lock_irq(&device_state_lock);
		if (hdev->state == USB_STATE_NOTATTACHED)
			status = -ENOTCONN;
		else
4763
			port_dev->child = udev;
L
Linus Torvalds 已提交
4764
		spin_unlock_irq(&device_state_lock);
4765
		mutex_unlock(&usb_port_peer_mutex);
L
Linus Torvalds 已提交
4766 4767 4768 4769 4770

		/* Run it through the hoops (find a driver, etc) */
		if (!status) {
			status = usb_new_device(udev);
			if (status) {
4771
				mutex_lock(&usb_port_peer_mutex);
L
Linus Torvalds 已提交
4772
				spin_lock_irq(&device_state_lock);
4773
				port_dev->child = NULL;
L
Linus Torvalds 已提交
4774
				spin_unlock_irq(&device_state_lock);
4775
				mutex_unlock(&usb_port_peer_mutex);
L
Linus Torvalds 已提交
4776 4777 4778 4779 4780 4781 4782 4783
			}
		}

		if (status)
			goto loop_disable;

		status = hub_power_remaining(hub);
		if (status)
4784
			dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
L
Linus Torvalds 已提交
4785 4786 4787 4788 4789 4790

		return;

loop_disable:
		hub_port_disable(hub, port1, 1);
loop:
4791
		usb_ep0_reinit(udev);
4792
		release_devnum(udev);
4793
		hub_free_dev(udev);
L
Linus Torvalds 已提交
4794
		usb_put_dev(udev);
4795
		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
L
Linus Torvalds 已提交
4796 4797
			break;
	}
4798 4799
	if (hub->hdev->parent ||
			!hcd->driver->port_handed_over ||
4800 4801
			!(hcd->driver->port_handed_over)(hcd, port1)) {
		if (status != -ENOTCONN && status != -ENODEV)
4802 4803
			dev_err(&port_dev->dev,
					"unable to enumerate USB device\n");
4804
	}
4805

L
Linus Torvalds 已提交
4806 4807
done:
	hub_port_disable(hub, port1, 1);
4808 4809
	if (hcd->driver->relinquish_port && !hub->hdev->parent)
		hcd->driver->relinquish_port(hcd, port1);
4810

L
Linus Torvalds 已提交
4811 4812
}

4813 4814 4815 4816 4817 4818 4819 4820 4821 4822
/* Handle physical or logical connection change events.
 * This routine is called when:
 *	a port connection-change occurs;
 *	a port enable-change occurs (often caused by EMI);
 *	usb_reset_and_verify_device() encounters changed descriptors (as from
 *		a firmware download)
 * caller already locked the hub
 */
static void hub_port_connect_change(struct usb_hub *hub, int port1,
					u16 portstatus, u16 portchange)
D
Dan Williams 已提交
4823
		__must_hold(&port_dev->status_lock)
4824
{
4825 4826 4827
	struct usb_port *port_dev = hub->ports[port1 - 1];
	struct usb_device *udev = port_dev->child;
	int status = -ENODEV;
4828

4829 4830 4831 4832 4833 4834
	dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
			portchange, portspeed(hub, portstatus));

	if (hub->has_indicators) {
		set_port_led(hub, port1, HUB_LED_AUTO);
		hub->indicator[port1-1] = INDICATOR_AUTO;
4835 4836
	}

4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848 4849 4850 4851 4852 4853 4854
#ifdef	CONFIG_USB_OTG
	/* during HNP, don't repeat the debounce */
	if (hub->hdev->bus->is_b_host)
		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
				USB_PORT_STAT_C_ENABLE);
#endif

	/* Try to resuscitate an existing device */
	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
			udev->state != USB_STATE_NOTATTACHED) {
		if (portstatus & USB_PORT_STAT_ENABLE) {
			status = 0;		/* Nothing to do */
#ifdef CONFIG_PM_RUNTIME
		} else if (udev->state == USB_STATE_SUSPENDED &&
				udev->persist_enabled) {
			/* For a suspended device, treat this as a
			 * remote wakeup event.
			 */
D
Dan Williams 已提交
4855
			usb_unlock_port(port_dev);
4856
			status = usb_remote_wakeup(udev);
D
Dan Williams 已提交
4857
			usb_lock_port(port_dev);
4858 4859 4860 4861 4862 4863 4864
#endif
		} else {
			/* Don't resuscitate */;
		}
	}
	clear_bit(port1, hub->change_bits);

D
Dan Williams 已提交
4865
	/* successfully revalidated the connection */
4866 4867 4868
	if (status == 0)
		return;

D
Dan Williams 已提交
4869
	usb_unlock_port(port_dev);
4870
	hub_port_connect(hub, port1, portstatus, portchange);
D
Dan Williams 已提交
4871
	usb_lock_port(port_dev);
L
Linus Torvalds 已提交
4872 4873
}

4874
static void port_event(struct usb_hub *hub, int port1)
D
Dan Williams 已提交
4875
		__must_hold(&port_dev->status_lock)
4876 4877 4878 4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946
{
	int connect_change, reset_device = 0;
	struct usb_port *port_dev = hub->ports[port1 - 1];
	struct usb_device *udev = port_dev->child;
	struct usb_device *hdev = hub->hdev;
	u16 portstatus, portchange;

	connect_change = test_bit(port1, hub->change_bits);
	clear_bit(port1, hub->event_bits);
	clear_bit(port1, hub->wakeup_bits);

	if (hub_port_status(hub, port1, &portstatus, &portchange) < 0)
		return;

	if (portchange & USB_PORT_STAT_C_CONNECTION) {
		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
		connect_change = 1;
	}

	if (portchange & USB_PORT_STAT_C_ENABLE) {
		if (!connect_change)
			dev_dbg(&port_dev->dev, "enable change, status %08x\n",
					portstatus);
		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);

		/*
		 * EM interference sometimes causes badly shielded USB devices
		 * to be shutdown by the hub, this hack enables them again.
		 * Works at least with mouse driver.
		 */
		if (!(portstatus & USB_PORT_STAT_ENABLE)
		    && !connect_change && udev) {
			dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
			connect_change = 1;
		}
	}

	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
		u16 status = 0, unused;

		dev_dbg(&port_dev->dev, "over-current change\n");
		usb_clear_port_feature(hdev, port1,
				USB_PORT_FEAT_C_OVER_CURRENT);
		msleep(100);	/* Cool down */
		hub_power_on(hub, true);
		hub_port_status(hub, port1, &status, &unused);
		if (status & USB_PORT_STAT_OVERCURRENT)
			dev_err(&port_dev->dev, "over-current condition\n");
	}

	if (portchange & USB_PORT_STAT_C_RESET) {
		dev_dbg(&port_dev->dev, "reset change\n");
		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
	}
	if ((portchange & USB_PORT_STAT_C_BH_RESET)
	    && hub_is_superspeed(hdev)) {
		dev_dbg(&port_dev->dev, "warm reset change\n");
		usb_clear_port_feature(hdev, port1,
				USB_PORT_FEAT_C_BH_PORT_RESET);
	}
	if (portchange & USB_PORT_STAT_C_LINK_STATE) {
		dev_dbg(&port_dev->dev, "link state change\n");
		usb_clear_port_feature(hdev, port1,
				USB_PORT_FEAT_C_PORT_LINK_STATE);
	}
	if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
		dev_warn(&port_dev->dev, "config error\n");
		usb_clear_port_feature(hdev, port1,
				USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
	}

4947 4948 4949
	/* skip port actions that require the port to be powered on */
	if (!pm_runtime_active(&port_dev->dev))
		return;
4950

4951 4952 4953 4954 4955 4956 4957
	if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
		connect_change = 1;

	/*
	 * Warm reset a USB3 protocol port if it's in
	 * SS.Inactive state.
	 */
4958
	if (hub_port_warm_reset_required(hub, port1, portstatus)) {
4959 4960 4961 4962 4963 4964 4965 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981 4982
		dev_dbg(&port_dev->dev, "do warm reset\n");
		if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
				|| udev->state == USB_STATE_NOTATTACHED) {
			if (hub_port_reset(hub, port1, NULL,
					HUB_BH_RESET_TIME, true) < 0)
				hub_port_disable(hub, port1, 1);
		} else
			reset_device = 1;
	}

	/*
	 * On disconnect USB3 protocol ports transit from U0 to
	 * SS.Inactive to Rx.Detect. If this happens a warm-
	 * reset is not needed, but a (re)connect may happen
	 * before khubd runs and sees the disconnect, and the
	 * device may be an unknown state.
	 *
	 * If the port went through SS.Inactive without khubd
	 * seeing it the C_LINK_STATE change flag will be set,
	 * and we reset the dev to put it in a known state.
	 */
	if (reset_device || (udev && hub_is_superspeed(hub->hdev)
				&& (portchange & USB_PORT_STAT_C_LINK_STATE)
				&& (portstatus & USB_PORT_STAT_CONNECTION))) {
D
Dan Williams 已提交
4983
		usb_unlock_port(port_dev);
4984
		usb_lock_device(udev);
4985
		usb_reset_device(udev);
4986
		usb_unlock_device(udev);
D
Dan Williams 已提交
4987
		usb_lock_port(port_dev);
4988
		connect_change = 0;
4989
	}
4990 4991 4992

	if (connect_change)
		hub_port_connect_change(hub, port1, portstatus, portchange);
4993 4994
}

4995

L
Linus Torvalds 已提交
4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024 5025
static void hub_events(void)
{
	struct list_head *tmp;
	struct usb_device *hdev;
	struct usb_interface *intf;
	struct usb_hub *hub;
	struct device *hub_dev;
	u16 hubstatus;
	u16 hubchange;
	int i, ret;

	/*
	 *  We restart the list every time to avoid a deadlock with
	 * deleting hubs downstream from this one. This should be
	 * safe since we delete the hub from the event list.
	 * Not the most efficient, but avoids deadlocks.
	 */
	while (1) {

		/* Grab the first entry at the beginning of the list */
		spin_lock_irq(&hub_event_lock);
		if (list_empty(&hub_event_list)) {
			spin_unlock_irq(&hub_event_lock);
			break;
		}

		tmp = hub_event_list.next;
		list_del_init(tmp);

		hub = list_entry(tmp, struct usb_hub, event_list);
5026
		kref_get(&hub->kref);
5027 5028
		hdev = hub->hdev;
		usb_get_dev(hdev);
5029
		spin_unlock_irq(&hub_event_lock);
L
Linus Torvalds 已提交
5030

5031 5032
		hub_dev = hub->intfdev;
		intf = to_usb_interface(hub_dev);
5033
		dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
5034
				hdev->state, hdev->maxchild,
L
Linus Torvalds 已提交
5035 5036
				/* NOTE: expects max 15 ports... */
				(u16) hub->change_bits[0],
5037
				(u16) hub->event_bits[0]);
L
Linus Torvalds 已提交
5038 5039 5040

		/* Lock the device, then check to see if we were
		 * disconnected while waiting for the lock to succeed. */
5041
		usb_lock_device(hdev);
5042
		if (unlikely(hub->disconnected))
5043
			goto loop_disconnected;
L
Linus Torvalds 已提交
5044 5045 5046

		/* If the hub has died, clean up after it */
		if (hdev->state == USB_STATE_NOTATTACHED) {
5047
			hub->error = -ENODEV;
5048
			hub_quiesce(hub, HUB_DISCONNECT);
L
Linus Torvalds 已提交
5049 5050 5051
			goto loop;
		}

5052 5053 5054 5055 5056 5057
		/* Autoresume */
		ret = usb_autopm_get_interface(intf);
		if (ret) {
			dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
			goto loop;
		}
5058

5059
		/* If this is an inactive hub, do nothing */
L
Linus Torvalds 已提交
5060
		if (hub->quiescing)
5061
			goto loop_autopm;
L
Linus Torvalds 已提交
5062 5063 5064 5065 5066

		if (hub->error) {
			dev_dbg (hub_dev, "resetting for error %d\n",
				hub->error);

5067
			ret = usb_reset_device(hdev);
L
Linus Torvalds 已提交
5068 5069 5070
			if (ret) {
				dev_dbg (hub_dev,
					"error resetting hub: %d\n", ret);
5071
				goto loop_autopm;
L
Linus Torvalds 已提交
5072 5073 5074 5075 5076 5077 5078
			}

			hub->nerrors = 0;
			hub->error = 0;
		}

		/* deal with port status changes */
5079
		for (i = 1; i <= hdev->maxchild; i++) {
5080
			struct usb_port *port_dev = hub->ports[i - 1];
L
Linus Torvalds 已提交
5081

D
Dan Williams 已提交
5082 5083 5084
			if (test_bit(i, hub->event_bits)
					|| test_bit(i, hub->change_bits)
					|| test_bit(i, hub->wakeup_bits)) {
L
Linus Torvalds 已提交
5085
				/*
5086 5087 5088 5089 5090 5091 5092
				 * The get_noresume and barrier ensure that if
				 * the port was in the process of resuming, we
				 * flush that work and keep the port active for
				 * the duration of the port_event().  However,
				 * if the port is runtime pm suspended
				 * (powered-off), we leave it in that state, run
				 * an abbreviated port_event(), and move on.
L
Linus Torvalds 已提交
5093
				 */
5094 5095
				pm_runtime_get_noresume(&port_dev->dev);
				pm_runtime_barrier(&port_dev->dev);
D
Dan Williams 已提交
5096
				usb_lock_port(port_dev);
5097
				port_event(hub, i);
D
Dan Williams 已提交
5098
				usb_unlock_port(port_dev);
5099
				pm_runtime_put_sync(&port_dev->dev);
J
John Youn 已提交
5100
			}
5101
		}
L
Linus Torvalds 已提交
5102 5103 5104 5105 5106 5107 5108 5109 5110 5111

		/* deal with hub status changes */
		if (test_and_clear_bit(0, hub->event_bits) == 0)
			;	/* do nothing */
		else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
			dev_err (hub_dev, "get_hub_status failed\n");
		else {
			if (hubchange & HUB_CHANGE_LOCAL_POWER) {
				dev_dbg (hub_dev, "power change\n");
				clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
5112 5113 5114
				if (hubstatus & HUB_STATUS_LOCAL_POWER)
					/* FIXME: Is this always true? */
					hub->limited_power = 1;
5115 5116
				else
					hub->limited_power = 0;
L
Linus Torvalds 已提交
5117 5118
			}
			if (hubchange & HUB_CHANGE_OVERCURRENT) {
5119 5120 5121 5122
				u16 status = 0;
				u16 unused;

				dev_dbg(hub_dev, "over-current change\n");
L
Linus Torvalds 已提交
5123
				clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
5124
				msleep(500);	/* Cool down */
5125
				hub_power_on(hub, true);
5126 5127 5128 5129
				hub_hub_status(hub, &status, &unused);
				if (status & HUB_STATUS_OVERCURRENT)
					dev_err(hub_dev, "over-current "
						"condition\n");
L
Linus Torvalds 已提交
5130 5131 5132
			}
		}

5133 5134 5135 5136 5137 5138 5139 5140
 loop_autopm:
		/* Balance the usb_autopm_get_interface() above */
		usb_autopm_put_interface_no_suspend(intf);
 loop:
		/* Balance the usb_autopm_get_interface_no_resume() in
		 * kick_khubd() and allow autosuspend.
		 */
		usb_autopm_put_interface(intf);
5141
 loop_disconnected:
L
Linus Torvalds 已提交
5142
		usb_unlock_device(hdev);
5143
		usb_put_dev(hdev);
5144
		kref_put(&hub->kref, hub_release);
L
Linus Torvalds 已提交
5145

5146
	} /* end while (1) */
L
Linus Torvalds 已提交
5147 5148 5149 5150
}

static int hub_thread(void *__unused)
{
5151
	/* khubd needs to be freezable to avoid interfering with USB-PERSIST
5152 5153 5154 5155
	 * port handover.  Otherwise it might see that a full-speed device
	 * was gone before the EHCI controller had handed its port over to
	 * the companion full-speed controller.
	 */
5156
	set_freezable();
5157

L
Linus Torvalds 已提交
5158 5159
	do {
		hub_events();
5160
		wait_event_freezable(khubd_wait,
5161 5162 5163
				!list_empty(&hub_event_list) ||
				kthread_should_stop());
	} while (!kthread_should_stop() || !list_empty(&hub_event_list));
L
Linus Torvalds 已提交
5164

5165 5166
	pr_debug("%s: khubd exiting\n", usbcore_name);
	return 0;
L
Linus Torvalds 已提交
5167 5168
}

5169
static const struct usb_device_id hub_id_table[] = {
5170
    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5171
			| USB_DEVICE_ID_MATCH_INT_CLASS,
5172 5173 5174
      .idVendor = USB_VENDOR_GENESYS_LOGIC,
      .bInterfaceClass = USB_CLASS_HUB,
      .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
L
Linus Torvalds 已提交
5175 5176 5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189
    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
      .bDeviceClass = USB_CLASS_HUB},
    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
      .bInterfaceClass = USB_CLASS_HUB},
    { }						/* Terminating entry */
};

MODULE_DEVICE_TABLE (usb, hub_id_table);

static struct usb_driver hub_driver = {
	.name =		"hub",
	.probe =	hub_probe,
	.disconnect =	hub_disconnect,
	.suspend =	hub_suspend,
	.resume =	hub_resume,
A
Alan Stern 已提交
5190
	.reset_resume =	hub_reset_resume,
5191 5192
	.pre_reset =	hub_pre_reset,
	.post_reset =	hub_post_reset,
5193
	.unlocked_ioctl = hub_ioctl,
L
Linus Torvalds 已提交
5194
	.id_table =	hub_id_table,
5195
	.supports_autosuspend =	1,
L
Linus Torvalds 已提交
5196 5197 5198 5199 5200 5201 5202 5203 5204 5205
};

int usb_hub_init(void)
{
	if (usb_register(&hub_driver) < 0) {
		printk(KERN_ERR "%s: can't register hub driver\n",
			usbcore_name);
		return -1;
	}

5206 5207
	khubd_task = kthread_run(hub_thread, NULL, "khubd");
	if (!IS_ERR(khubd_task))
L
Linus Torvalds 已提交
5208 5209 5210 5211 5212 5213 5214 5215 5216 5217 5218
		return 0;

	/* Fall through if kernel_thread failed */
	usb_deregister(&hub_driver);
	printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);

	return -1;
}

void usb_hub_cleanup(void)
{
5219
	kthread_stop(khubd_task);
L
Linus Torvalds 已提交
5220 5221 5222 5223 5224 5225 5226 5227 5228 5229 5230

	/*
	 * Hub resources are freed for us by usb_deregister. It calls
	 * usb_driver_purge on every device which in turn calls that
	 * devices disconnect function if it is using this driver.
	 * The hub_disconnect function takes care of releasing the
	 * individual hub resources. -greg
	 */
	usb_deregister(&hub_driver);
} /* usb_hub_cleanup() */

5231
static int descriptors_changed(struct usb_device *udev,
5232 5233
		struct usb_device_descriptor *old_device_descriptor,
		struct usb_host_bos *old_bos)
5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244 5245 5246
{
	int		changed = 0;
	unsigned	index;
	unsigned	serial_len = 0;
	unsigned	len;
	unsigned	old_length;
	int		length;
	char		*buf;

	if (memcmp(&udev->descriptor, old_device_descriptor,
			sizeof(*old_device_descriptor)) != 0)
		return 1;

5247 5248 5249
	if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
		return 1;
	if (udev->bos) {
5250 5251
		len = le16_to_cpu(udev->bos->desc->wTotalLength);
		if (len != le16_to_cpu(old_bos->desc->wTotalLength))
5252
			return 1;
5253
		if (memcmp(udev->bos->desc, old_bos->desc, len))
5254 5255 5256
			return 1;
	}

5257 5258 5259 5260 5261 5262 5263 5264
	/* Since the idVendor, idProduct, and bcdDevice values in the
	 * device descriptor haven't changed, we will assume the
	 * Manufacturer and Product strings haven't changed either.
	 * But the SerialNumber string could be different (e.g., a
	 * different flash card of the same brand).
	 */
	if (udev->serial)
		serial_len = strlen(udev->serial) + 1;
L
Linus Torvalds 已提交
5265

5266
	len = serial_len;
L
Linus Torvalds 已提交
5267
	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5268 5269
		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
		len = max(len, old_length);
L
Linus Torvalds 已提交
5270
	}
5271

O
Oliver Neukum 已提交
5272
	buf = kmalloc(len, GFP_NOIO);
L
Linus Torvalds 已提交
5273 5274 5275 5276 5277 5278
	if (buf == NULL) {
		dev_err(&udev->dev, "no mem to re-read configs after reset\n");
		/* assume the worst */
		return 1;
	}
	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5279
		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
L
Linus Torvalds 已提交
5280 5281
		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
				old_length);
5282
		if (length != old_length) {
L
Linus Torvalds 已提交
5283 5284
			dev_dbg(&udev->dev, "config index %d, error %d\n",
					index, length);
5285
			changed = 1;
L
Linus Torvalds 已提交
5286 5287 5288 5289 5290
			break;
		}
		if (memcmp (buf, udev->rawdescriptors[index], old_length)
				!= 0) {
			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
5291 5292 5293 5294
				index,
				((struct usb_config_descriptor *) buf)->
					bConfigurationValue);
			changed = 1;
L
Linus Torvalds 已提交
5295 5296 5297
			break;
		}
	}
5298 5299 5300 5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311

	if (!changed && serial_len) {
		length = usb_string(udev, udev->descriptor.iSerialNumber,
				buf, serial_len);
		if (length + 1 != serial_len) {
			dev_dbg(&udev->dev, "serial string error %d\n",
					length);
			changed = 1;
		} else if (memcmp(buf, udev->serial, length) != 0) {
			dev_dbg(&udev->dev, "serial string changed\n");
			changed = 1;
		}
	}

L
Linus Torvalds 已提交
5312
	kfree(buf);
5313
	return changed;
L
Linus Torvalds 已提交
5314 5315 5316
}

/**
5317
 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
L
Linus Torvalds 已提交
5318 5319
 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
 *
5320 5321
 * WARNING - don't use this routine to reset a composite device
 * (one with multiple interfaces owned by separate drivers)!
5322
 * Use usb_reset_device() instead.
L
Linus Torvalds 已提交
5323 5324 5325 5326 5327 5328 5329 5330 5331
 *
 * Do a port reset, reassign the device's address, and establish its
 * former operating configuration.  If the reset fails, or the device's
 * descriptors change from their values before the reset, or the original
 * configuration and altsettings cannot be restored, a flag will be set
 * telling khubd to pretend the device has been disconnected and then
 * re-connected.  All drivers will be unbound, and the device will be
 * re-enumerated and probed all over again.
 *
5332
 * Return: 0 if the reset succeeded, -ENODEV if the device has been
L
Linus Torvalds 已提交
5333 5334 5335
 * flagged for logical disconnection, or some other negative error code
 * if the reset wasn't even attempted.
 *
5336
 * Note:
D
Dan Williams 已提交
5337 5338 5339 5340 5341
 * The caller must own the device lock and the port lock, the latter is
 * taken by usb_reset_device().  For example, it's safe to use
 * usb_reset_device() from a driver probe() routine after downloading
 * new firmware.  For calls that might not occur during probe(), drivers
 * should lock the device using usb_lock_device_for_reset().
A
Alan Stern 已提交
5342 5343 5344 5345
 *
 * Locking exception: This routine may also be called from within an
 * autoresume handler.  Such usage won't conflict with other tasks
 * holding the device lock because these tasks should always call
D
Dan Williams 已提交
5346 5347 5348
 * usb_autopm_resume_device(), thereby preventing any unwanted
 * autoresume.  The autoresume handler is expected to have already
 * acquired the port lock before calling this routine.
L
Linus Torvalds 已提交
5349
 */
5350
static int usb_reset_and_verify_device(struct usb_device *udev)
L
Linus Torvalds 已提交
5351 5352 5353
{
	struct usb_device		*parent_hdev = udev->parent;
	struct usb_hub			*parent_hub;
5354
	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
L
Linus Torvalds 已提交
5355
	struct usb_device_descriptor	descriptor = udev->descriptor;
5356
	struct usb_host_bos		*bos;
5357
	int				i, j, ret = 0;
5358
	int				port1 = udev->portnum;
L
Linus Torvalds 已提交
5359 5360 5361 5362 5363 5364 5365 5366

	if (udev->state == USB_STATE_NOTATTACHED ||
			udev->state == USB_STATE_SUSPENDED) {
		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
				udev->state);
		return -EINVAL;
	}

D
Dan Williams 已提交
5367
	if (!parent_hdev)
L
Linus Torvalds 已提交
5368
		return -EISDIR;
D
Dan Williams 已提交
5369

5370
	parent_hub = usb_hub_to_struct_hub(parent_hdev);
L
Linus Torvalds 已提交
5371

5372 5373 5374 5375 5376 5377
	/* Disable USB2 hardware LPM.
	 * It will be re-enabled by the enumeration process.
	 */
	if (udev->usb2_hw_lpm_enabled == 1)
		usb_set_usb2_hardware_lpm(udev, 0);

5378 5379 5380
	bos = udev->bos;
	udev->bos = NULL;

5381 5382 5383 5384
	/* Disable LPM and LTM while we reset the device and reinstall the alt
	 * settings.  Device-initiated LPM settings, and system exit latency
	 * settings are cleared when the device is reset, so we have to set
	 * them up again.
5385 5386 5387 5388 5389 5390
	 */
	ret = usb_unlocked_disable_lpm(udev);
	if (ret) {
		dev_err(&udev->dev, "%s Failed to disable LPM\n.", __func__);
		goto re_enumerate;
	}
5391 5392 5393 5394 5395 5396
	ret = usb_disable_ltm(udev);
	if (ret) {
		dev_err(&udev->dev, "%s Failed to disable LTM\n.",
				__func__);
		goto re_enumerate;
	}
5397

L
Linus Torvalds 已提交
5398 5399 5400 5401
	for (i = 0; i < SET_CONFIG_TRIES; ++i) {

		/* ep0 maxpacket size may change; let the HCD know about it.
		 * Other endpoints will be handled by re-enumeration. */
5402
		usb_ep0_reinit(udev);
L
Linus Torvalds 已提交
5403
		ret = hub_port_init(parent_hub, udev, port1, i);
5404
		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
L
Linus Torvalds 已提交
5405 5406
			break;
	}
5407

L
Linus Torvalds 已提交
5408 5409
	if (ret < 0)
		goto re_enumerate;
5410

L
Linus Torvalds 已提交
5411
	/* Device might have changed firmware (DFU or similar) */
5412
	if (descriptors_changed(udev, &descriptor, bos)) {
L
Linus Torvalds 已提交
5413 5414 5415
		dev_info(&udev->dev, "device firmware changed\n");
		udev->descriptor = descriptor;	/* for disconnect() calls */
		goto re_enumerate;
5416
	}
5417 5418

	/* Restore the device's previous configuration */
L
Linus Torvalds 已提交
5419 5420
	if (!udev->actconfig)
		goto done;
5421

5422
	mutex_lock(hcd->bandwidth_mutex);
5423 5424 5425 5426 5427
	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
	if (ret < 0) {
		dev_warn(&udev->dev,
				"Busted HC?  Not enough HCD resources for "
				"old configuration.\n");
5428
		mutex_unlock(hcd->bandwidth_mutex);
5429 5430
		goto re_enumerate;
	}
L
Linus Torvalds 已提交
5431 5432 5433 5434 5435 5436 5437 5438
	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
			USB_REQ_SET_CONFIGURATION, 0,
			udev->actconfig->desc.bConfigurationValue, 0,
			NULL, 0, USB_CTRL_SET_TIMEOUT);
	if (ret < 0) {
		dev_err(&udev->dev,
			"can't restore configuration #%d (error=%d)\n",
			udev->actconfig->desc.bConfigurationValue, ret);
5439
		mutex_unlock(hcd->bandwidth_mutex);
L
Linus Torvalds 已提交
5440
		goto re_enumerate;
5441
	}
5442
	mutex_unlock(hcd->bandwidth_mutex);
L
Linus Torvalds 已提交
5443 5444
	usb_set_device_state(udev, USB_STATE_CONFIGURED);

5445 5446 5447 5448 5449 5450
	/* Put interfaces back into the same altsettings as before.
	 * Don't bother to send the Set-Interface request for interfaces
	 * that were already in altsetting 0; besides being unnecessary,
	 * many devices can't handle it.  Instead just reset the host-side
	 * endpoint state.
	 */
L
Linus Torvalds 已提交
5451
	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
5452 5453
		struct usb_host_config *config = udev->actconfig;
		struct usb_interface *intf = config->interface[i];
L
Linus Torvalds 已提交
5454 5455 5456
		struct usb_interface_descriptor *desc;

		desc = &intf->cur_altsetting->desc;
5457 5458 5459 5460 5461
		if (desc->bAlternateSetting == 0) {
			usb_disable_interface(udev, intf, true);
			usb_enable_interface(udev, intf, true);
			ret = 0;
		} else {
5462 5463 5464
			/* Let the bandwidth allocation function know that this
			 * device has been reset, and it will have to use
			 * alternate setting 0 as the current alternate setting.
5465
			 */
5466
			intf->resetting_device = 1;
5467 5468
			ret = usb_set_interface(udev, desc->bInterfaceNumber,
					desc->bAlternateSetting);
5469
			intf->resetting_device = 0;
5470
		}
L
Linus Torvalds 已提交
5471 5472 5473 5474 5475 5476 5477 5478
		if (ret < 0) {
			dev_err(&udev->dev, "failed to restore interface %d "
				"altsetting %d (error=%d)\n",
				desc->bInterfaceNumber,
				desc->bAlternateSetting,
				ret);
			goto re_enumerate;
		}
5479 5480 5481
		/* Resetting also frees any allocated streams */
		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
			intf->cur_altsetting->endpoint[j].streams = 0;
L
Linus Torvalds 已提交
5482 5483 5484
	}

done:
5485
	/* Now that the alt settings are re-installed, enable LTM and LPM. */
5486
	usb_set_usb2_hardware_lpm(udev, 1);
5487
	usb_unlocked_enable_lpm(udev);
5488
	usb_enable_ltm(udev);
5489 5490
	usb_release_bos_descriptor(udev);
	udev->bos = bos;
L
Linus Torvalds 已提交
5491
	return 0;
5492

L
Linus Torvalds 已提交
5493
re_enumerate:
5494
	/* LPM state doesn't matter when we're about to destroy the device. */
L
Linus Torvalds 已提交
5495
	hub_port_logical_disconnect(parent_hub, port1);
5496 5497
	usb_release_bos_descriptor(udev);
	udev->bos = bos;
L
Linus Torvalds 已提交
5498 5499
	return -ENODEV;
}
5500 5501

/**
5502
 * usb_reset_device - warn interface drivers and perform a USB port reset
5503 5504 5505 5506 5507 5508
 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
 *
 * Warns all drivers bound to registered interfaces (using their pre_reset
 * method), performs the port reset, and then lets the drivers know that
 * the reset is over (using their post_reset method).
 *
5509
 * Return: The same as for usb_reset_and_verify_device().
5510
 *
5511
 * Note:
5512 5513 5514 5515
 * The caller must own the device lock.  For example, it's safe to use
 * this from a driver probe() routine after downloading new firmware.
 * For calls that might not occur during probe(), drivers should lock
 * the device using usb_lock_device_for_reset().
5516 5517 5518 5519 5520
 *
 * If an interface is currently being probed or disconnected, we assume
 * its driver knows how to handle resets.  For all other interfaces,
 * if the driver doesn't have pre_reset and post_reset methods then
 * we attempt to unbind it and rebind afterward.
5521
 */
5522
int usb_reset_device(struct usb_device *udev)
5523 5524
{
	int ret;
5525
	int i;
5526
	unsigned int noio_flag;
D
Dan Williams 已提交
5527
	struct usb_port *port_dev;
5528
	struct usb_host_config *config = udev->actconfig;
D
Dan Williams 已提交
5529
	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
5530 5531 5532 5533 5534 5535 5536 5537

	if (udev->state == USB_STATE_NOTATTACHED ||
			udev->state == USB_STATE_SUSPENDED) {
		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
				udev->state);
		return -EINVAL;
	}

D
Dan Williams 已提交
5538 5539 5540 5541 5542 5543 5544 5545
	if (!udev->parent) {
		/* this requires hcd-specific logic; see ohci_restart() */
		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
		return -EISDIR;
	}

	port_dev = hub->ports[udev->portnum - 1];

5546 5547 5548 5549 5550 5551 5552 5553 5554 5555 5556
	/*
	 * Don't allocate memory with GFP_KERNEL in current
	 * context to avoid possible deadlock if usb mass
	 * storage interface or usbnet interface(iSCSI case)
	 * is included in current configuration. The easist
	 * approach is to do it for every device reset,
	 * because the device 'memalloc_noio' flag may have
	 * not been set before reseting the usb device.
	 */
	noio_flag = memalloc_noio_save();

5557
	/* Prevent autosuspend during the reset */
5558
	usb_autoresume_device(udev);
5559

5560 5561
	if (config) {
		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
5562 5563
			struct usb_interface *cintf = config->interface[i];
			struct usb_driver *drv;
5564
			int unbind = 0;
5565 5566

			if (cintf->dev.driver) {
5567
				drv = to_usb_driver(cintf->dev.driver);
5568 5569 5570 5571 5572 5573 5574
				if (drv->pre_reset && drv->post_reset)
					unbind = (drv->pre_reset)(cintf);
				else if (cintf->condition ==
						USB_INTERFACE_BOUND)
					unbind = 1;
				if (unbind)
					usb_forced_unbind_intf(cintf);
5575 5576 5577 5578
			}
		}
	}

D
Dan Williams 已提交
5579
	usb_lock_port(port_dev);
5580
	ret = usb_reset_and_verify_device(udev);
D
Dan Williams 已提交
5581
	usb_unlock_port(port_dev);
5582 5583 5584

	if (config) {
		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
5585 5586
			struct usb_interface *cintf = config->interface[i];
			struct usb_driver *drv;
5587
			int rebind = cintf->needs_binding;
5588

5589
			if (!rebind && cintf->dev.driver) {
5590 5591
				drv = to_usb_driver(cintf->dev.driver);
				if (drv->post_reset)
5592 5593 5594 5595
					rebind = (drv->post_reset)(cintf);
				else if (cintf->condition ==
						USB_INTERFACE_BOUND)
					rebind = 1;
5596 5597
				if (rebind)
					cintf->needs_binding = 1;
5598 5599
			}
		}
5600
		usb_unbind_and_rebind_marked_interfaces(udev);
5601 5602
	}

5603
	usb_autosuspend_device(udev);
5604
	memalloc_noio_restore(noio_flag);
5605 5606
	return ret;
}
5607
EXPORT_SYMBOL_GPL(usb_reset_device);
5608 5609 5610 5611 5612 5613 5614 5615 5616 5617 5618 5619 5620 5621 5622 5623 5624 5625 5626 5627 5628 5629 5630 5631 5632 5633 5634 5635 5636 5637 5638 5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650


/**
 * usb_queue_reset_device - Reset a USB device from an atomic context
 * @iface: USB interface belonging to the device to reset
 *
 * This function can be used to reset a USB device from an atomic
 * context, where usb_reset_device() won't work (as it blocks).
 *
 * Doing a reset via this method is functionally equivalent to calling
 * usb_reset_device(), except for the fact that it is delayed to a
 * workqueue. This means that any drivers bound to other interfaces
 * might be unbound, as well as users from usbfs in user space.
 *
 * Corner cases:
 *
 * - Scheduling two resets at the same time from two different drivers
 *   attached to two different interfaces of the same device is
 *   possible; depending on how the driver attached to each interface
 *   handles ->pre_reset(), the second reset might happen or not.
 *
 * - If a driver is unbound and it had a pending reset, the reset will
 *   be cancelled.
 *
 * - This function can be called during .probe() or .disconnect()
 *   times. On return from .disconnect(), any pending resets will be
 *   cancelled.
 *
 * There is no no need to lock/unlock the @reset_ws as schedule_work()
 * does its own.
 *
 * NOTE: We don't do any reference count tracking because it is not
 *     needed. The lifecycle of the work_struct is tied to the
 *     usb_interface. Before destroying the interface we cancel the
 *     work_struct, so the fact that work_struct is queued and or
 *     running means the interface (and thus, the device) exist and
 *     are referenced.
 */
void usb_queue_reset_device(struct usb_interface *iface)
{
	schedule_work(&iface->reset_ws);
}
EXPORT_SYMBOL_GPL(usb_queue_reset_device);
5651 5652 5653 5654 5655 5656 5657 5658 5659 5660 5661

/**
 * usb_hub_find_child - Get the pointer of child device
 * attached to the port which is specified by @port1.
 * @hdev: USB device belonging to the usb hub
 * @port1: port num to indicate which port the child device
 *	is attached to.
 *
 * USB drivers call this function to get hub's child device
 * pointer.
 *
5662
 * Return: %NULL if input param is invalid and
5663 5664 5665 5666 5667
 * child's usb_device pointer if non-NULL.
 */
struct usb_device *usb_hub_find_child(struct usb_device *hdev,
		int port1)
{
5668
	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
5669 5670 5671 5672 5673 5674

	if (port1 < 1 || port1 > hdev->maxchild)
		return NULL;
	return hub->ports[port1 - 1]->child;
}
EXPORT_SYMBOL_GPL(usb_hub_find_child);
5675

5676 5677 5678
void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
		struct usb_hub_descriptor *desc)
{
5679
	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
5680 5681 5682
	enum usb_port_connect_type connect_type;
	int i;

5683 5684 5685
	if (!hub)
		return;

5686 5687
	if (!hub_is_superspeed(hdev)) {
		for (i = 1; i <= hdev->maxchild; i++) {
5688
			struct usb_port *port_dev = hub->ports[i - 1];
5689

5690
			connect_type = port_dev->connect_type;
5691 5692 5693 5694
			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
				u8 mask = 1 << (i%8);

				if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
5695
					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
5696 5697 5698 5699 5700 5701 5702 5703
					desc->u.hs.DeviceRemovable[i/8]	|= mask;
				}
			}
		}
	} else {
		u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);

		for (i = 1; i <= hdev->maxchild; i++) {
5704
			struct usb_port *port_dev = hub->ports[i - 1];
5705

5706
			connect_type = port_dev->connect_type;
5707 5708 5709 5710
			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
				u16 mask = 1 << i;

				if (!(port_removable & mask)) {
5711
					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
5712 5713 5714 5715 5716 5717 5718 5719 5720
					port_removable |= mask;
				}
			}
		}

		desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
	}
}

5721 5722 5723 5724 5725 5726
#ifdef CONFIG_ACPI
/**
 * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
 * @hdev: USB device belonging to the usb hub
 * @port1: port num of the port
 *
5727 5728
 * Return: Port's acpi handle if successful, %NULL if params are
 * invalid.
5729 5730 5731 5732
 */
acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
	int port1)
{
5733
	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
5734

5735 5736 5737
	if (!hub)
		return NULL;

5738
	return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
5739 5740
}
#endif