hcd.c 78.9 KB
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/*
 * (C) Copyright Linus Torvalds 1999
 * (C) Copyright Johannes Erdfelt 1999-2001
 * (C) Copyright Andreas Gal 1999
 * (C) Copyright Gregory P. Smith 1999
 * (C) Copyright Deti Fliegl 1999
 * (C) Copyright Randy Dunlap 2000
 * (C) Copyright David Brownell 2000-2002
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

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#include <linux/bcd.h>
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#include <linux/module.h>
#include <linux/version.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/completion.h>
#include <linux/utsname.h>
#include <linux/mm.h>
#include <asm/io.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
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#include <linux/mutex.h>
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#include <asm/irq.h>
#include <asm/byteorder.h>
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#include <asm/unaligned.h>
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#include <linux/platform_device.h>
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#include <linux/workqueue.h>
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#include <linux/pm_runtime.h>
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#include <linux/usb.h>
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#include <linux/usb/hcd.h>
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#include "usb.h"


/*-------------------------------------------------------------------------*/

/*
 * USB Host Controller Driver framework
 *
 * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
 * HCD-specific behaviors/bugs.
 *
 * This does error checks, tracks devices and urbs, and delegates to a
 * "hc_driver" only for code (and data) that really needs to know about
 * hardware differences.  That includes root hub registers, i/o queues,
 * and so on ... but as little else as possible.
 *
 * Shared code includes most of the "root hub" code (these are emulated,
 * though each HC's hardware works differently) and PCI glue, plus request
 * tracking overhead.  The HCD code should only block on spinlocks or on
 * hardware handshaking; blocking on software events (such as other kernel
 * threads releasing resources, or completing actions) is all generic.
 *
 * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
 * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
 * only by the hub driver ... and that neither should be seen or used by
 * usb client device drivers.
 *
 * Contributors of ideas or unattributed patches include: David Brownell,
 * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
 *
 * HISTORY:
 * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
 *		associated cleanup.  "usb_hcd" still != "usb_bus".
 * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
 */

/*-------------------------------------------------------------------------*/

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/* Keep track of which host controller drivers are loaded */
unsigned long usb_hcds_loaded;
EXPORT_SYMBOL_GPL(usb_hcds_loaded);

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/* host controllers we manage */
LIST_HEAD (usb_bus_list);
EXPORT_SYMBOL_GPL (usb_bus_list);

/* used when allocating bus numbers */
#define USB_MAXBUS		64
struct usb_busmap {
	unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))];
};
static struct usb_busmap busmap;

/* used when updating list of hcds */
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DEFINE_MUTEX(usb_bus_list_lock);	/* exported only for usbfs */
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EXPORT_SYMBOL_GPL (usb_bus_list_lock);

/* used for controlling access to virtual root hubs */
static DEFINE_SPINLOCK(hcd_root_hub_lock);

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/* used when updating an endpoint's URB list */
static DEFINE_SPINLOCK(hcd_urb_list_lock);
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/* used to protect against unlinking URBs after the device is gone */
static DEFINE_SPINLOCK(hcd_urb_unlink_lock);

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/* wait queue for synchronous unlinks */
DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);

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static inline int is_root_hub(struct usb_device *udev)
{
	return (udev->parent == NULL);
}

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/*-------------------------------------------------------------------------*/

/*
 * Sharable chunks of root hub code.
 */

/*-------------------------------------------------------------------------*/
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#define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
#define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
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/* usb 3.0 root hub device descriptor */
static const u8 usb3_rh_dev_descriptor[18] = {
	0x12,       /*  __u8  bLength; */
	0x01,       /*  __u8  bDescriptorType; Device */
	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */

	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
	0x00,	    /*  __u8  bDeviceSubClass; */
	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */

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	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
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	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
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	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */

	0x03,       /*  __u8  iManufacturer; */
	0x02,       /*  __u8  iProduct; */
	0x01,       /*  __u8  iSerialNumber; */
	0x01        /*  __u8  bNumConfigurations; */
};

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/* usb 2.0 root hub device descriptor */
static const u8 usb2_rh_dev_descriptor [18] = {
	0x12,       /*  __u8  bLength; */
	0x01,       /*  __u8  bDescriptorType; Device */
	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */

	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
	0x00,	    /*  __u8  bDeviceSubClass; */
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	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
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	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
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	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
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	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
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	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */

	0x03,       /*  __u8  iManufacturer; */
	0x02,       /*  __u8  iProduct; */
	0x01,       /*  __u8  iSerialNumber; */
	0x01        /*  __u8  bNumConfigurations; */
};

/* no usb 2.0 root hub "device qualifier" descriptor: one speed only */

/* usb 1.1 root hub device descriptor */
static const u8 usb11_rh_dev_descriptor [18] = {
	0x12,       /*  __u8  bLength; */
	0x01,       /*  __u8  bDescriptorType; Device */
	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */

	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
	0x00,	    /*  __u8  bDeviceSubClass; */
	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
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	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
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	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
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	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
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	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */

	0x03,       /*  __u8  iManufacturer; */
	0x02,       /*  __u8  iProduct; */
	0x01,       /*  __u8  iSerialNumber; */
	0x01        /*  __u8  bNumConfigurations; */
};


/*-------------------------------------------------------------------------*/

/* Configuration descriptors for our root hubs */

static const u8 fs_rh_config_descriptor [] = {

	/* one configuration */
	0x09,       /*  __u8  bLength; */
	0x02,       /*  __u8  bDescriptorType; Configuration */
	0x19, 0x00, /*  __le16 wTotalLength; */
	0x01,       /*  __u8  bNumInterfaces; (1) */
	0x01,       /*  __u8  bConfigurationValue; */
	0x00,       /*  __u8  iConfiguration; */
	0xc0,       /*  __u8  bmAttributes; 
				 Bit 7: must be set,
				     6: Self-powered,
				     5: Remote wakeup,
				     4..0: resvd */
	0x00,       /*  __u8  MaxPower; */
      
	/* USB 1.1:
	 * USB 2.0, single TT organization (mandatory):
	 *	one interface, protocol 0
	 *
	 * USB 2.0, multiple TT organization (optional):
	 *	two interfaces, protocols 1 (like single TT)
	 *	and 2 (multiple TT mode) ... config is
	 *	sometimes settable
	 *	NOT IMPLEMENTED
	 */

	/* one interface */
	0x09,       /*  __u8  if_bLength; */
	0x04,       /*  __u8  if_bDescriptorType; Interface */
	0x00,       /*  __u8  if_bInterfaceNumber; */
	0x00,       /*  __u8  if_bAlternateSetting; */
	0x01,       /*  __u8  if_bNumEndpoints; */
	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
	0x00,       /*  __u8  if_bInterfaceSubClass; */
	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
	0x00,       /*  __u8  if_iInterface; */
     
	/* one endpoint (status change endpoint) */
	0x07,       /*  __u8  ep_bLength; */
	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
};

static const u8 hs_rh_config_descriptor [] = {

	/* one configuration */
	0x09,       /*  __u8  bLength; */
	0x02,       /*  __u8  bDescriptorType; Configuration */
	0x19, 0x00, /*  __le16 wTotalLength; */
	0x01,       /*  __u8  bNumInterfaces; (1) */
	0x01,       /*  __u8  bConfigurationValue; */
	0x00,       /*  __u8  iConfiguration; */
	0xc0,       /*  __u8  bmAttributes; 
				 Bit 7: must be set,
				     6: Self-powered,
				     5: Remote wakeup,
				     4..0: resvd */
	0x00,       /*  __u8  MaxPower; */
      
	/* USB 1.1:
	 * USB 2.0, single TT organization (mandatory):
	 *	one interface, protocol 0
	 *
	 * USB 2.0, multiple TT organization (optional):
	 *	two interfaces, protocols 1 (like single TT)
	 *	and 2 (multiple TT mode) ... config is
	 *	sometimes settable
	 *	NOT IMPLEMENTED
	 */

	/* one interface */
	0x09,       /*  __u8  if_bLength; */
	0x04,       /*  __u8  if_bDescriptorType; Interface */
	0x00,       /*  __u8  if_bInterfaceNumber; */
	0x00,       /*  __u8  if_bAlternateSetting; */
	0x01,       /*  __u8  if_bNumEndpoints; */
	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
	0x00,       /*  __u8  if_bInterfaceSubClass; */
	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
	0x00,       /*  __u8  if_iInterface; */
     
	/* one endpoint (status change endpoint) */
	0x07,       /*  __u8  ep_bLength; */
	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
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		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
		     * see hub.c:hub_configure() for details. */
	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
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	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
};

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static const u8 ss_rh_config_descriptor[] = {
	/* one configuration */
	0x09,       /*  __u8  bLength; */
	0x02,       /*  __u8  bDescriptorType; Configuration */
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	0x1f, 0x00, /*  __le16 wTotalLength; */
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	0x01,       /*  __u8  bNumInterfaces; (1) */
	0x01,       /*  __u8  bConfigurationValue; */
	0x00,       /*  __u8  iConfiguration; */
	0xc0,       /*  __u8  bmAttributes;
				 Bit 7: must be set,
				     6: Self-powered,
				     5: Remote wakeup,
				     4..0: resvd */
	0x00,       /*  __u8  MaxPower; */

	/* one interface */
	0x09,       /*  __u8  if_bLength; */
	0x04,       /*  __u8  if_bDescriptorType; Interface */
	0x00,       /*  __u8  if_bInterfaceNumber; */
	0x00,       /*  __u8  if_bAlternateSetting; */
	0x01,       /*  __u8  if_bNumEndpoints; */
	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
	0x00,       /*  __u8  if_bInterfaceSubClass; */
	0x00,       /*  __u8  if_bInterfaceProtocol; */
	0x00,       /*  __u8  if_iInterface; */

	/* one endpoint (status change endpoint) */
	0x07,       /*  __u8  ep_bLength; */
	0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
		     * see hub.c:hub_configure() for details. */
	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
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	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */

	/* one SuperSpeed endpoint companion descriptor */
	0x06,        /* __u8 ss_bLength */
	0x30,        /* __u8 ss_bDescriptorType; SuperSpeed EP Companion */
	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
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};

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/* authorized_default behaviour:
 * -1 is authorized for all devices except wireless (old behaviour)
 * 0 is unauthorized for all devices
 * 1 is authorized for all devices
 */
static int authorized_default = -1;
module_param(authorized_default, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(authorized_default,
		"Default USB device authorization: 0 is not authorized, 1 is "
		"authorized, -1 is authorized except for wireless USB (default, "
		"old behaviour");
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/*-------------------------------------------------------------------------*/

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/**
 * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
 * @s: Null-terminated ASCII (actually ISO-8859-1) string
 * @buf: Buffer for USB string descriptor (header + UTF-16LE)
 * @len: Length (in bytes; may be odd) of descriptor buffer.
 *
 * The return value is the number of bytes filled in: 2 + 2*strlen(s) or
 * buflen, whichever is less.
 *
 * USB String descriptors can contain at most 126 characters; input
 * strings longer than that are truncated.
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 */
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static unsigned
ascii2desc(char const *s, u8 *buf, unsigned len)
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{
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	unsigned n, t = 2 + 2*strlen(s);

	if (t > 254)
		t = 254;	/* Longest possible UTF string descriptor */
	if (len > t)
		len = t;

	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */

	n = len;
	while (n--) {
		*buf++ = t;
		if (!n--)
			break;
		*buf++ = t >> 8;
		t = (unsigned char)*s++;
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	}
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	return len;
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}

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/**
 * rh_string() - provides string descriptors for root hub
 * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
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 * @hcd: the host controller for this root hub
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 * @data: buffer for output packet
 * @len: length of the provided buffer
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 *
 * Produces either a manufacturer, product or serial number string for the
 * virtual root hub device.
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 * Returns the number of bytes filled in: the length of the descriptor or
 * of the provided buffer, whichever is less.
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 */
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static unsigned
rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
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{
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	char buf[100];
	char const *s;
	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
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	// language ids
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	switch (id) {
	case 0:
		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
		if (len > 4)
			len = 4;
		memcpy(data, langids, len);
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		return len;
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	case 1:
		/* Serial number */
		s = hcd->self.bus_name;
		break;
	case 2:
		/* Product name */
		s = hcd->product_desc;
		break;
	case 3:
		/* Manufacturer */
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		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
			init_utsname()->release, hcd->driver->description);
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		s = buf;
		break;
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	default:
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		/* Can't happen; caller guarantees it */
		return 0;
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	}
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	return ascii2desc(s, data, len);
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}


/* Root hub control transfers execute synchronously */
static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
{
	struct usb_ctrlrequest *cmd;
 	u16		typeReq, wValue, wIndex, wLength;
	u8		*ubuf = urb->transfer_buffer;
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	/*
	 * tbuf should be as big as the BOS descriptor and
	 * the USB hub descriptor.
	 */
	u8		tbuf[USB_DT_BOS_SIZE + USB_DT_USB_SS_CAP_SIZE]
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		__attribute__((aligned(4)));
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	const u8	*bufp = tbuf;
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	unsigned	len = 0;
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	int		status;
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	u8		patch_wakeup = 0;
	u8		patch_protocol = 0;
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	might_sleep();

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	spin_lock_irq(&hcd_root_hub_lock);
	status = usb_hcd_link_urb_to_ep(hcd, urb);
	spin_unlock_irq(&hcd_root_hub_lock);
	if (status)
		return status;
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	urb->hcpriv = hcd;	/* Indicate it's queued */
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	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
	wValue   = le16_to_cpu (cmd->wValue);
	wIndex   = le16_to_cpu (cmd->wIndex);
	wLength  = le16_to_cpu (cmd->wLength);

	if (wLength > urb->transfer_buffer_length)
		goto error;

	urb->actual_length = 0;
	switch (typeReq) {

	/* DEVICE REQUESTS */

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	/* The root hub's remote wakeup enable bit is implemented using
	 * driver model wakeup flags.  If this system supports wakeup
	 * through USB, userspace may change the default "allow wakeup"
	 * policy through sysfs or these calls.
	 *
	 * Most root hubs support wakeup from downstream devices, for
	 * runtime power management (disabling USB clocks and reducing
	 * VBUS power usage).  However, not all of them do so; silicon,
	 * board, and BIOS bugs here are not uncommon, so these can't
	 * be treated quite like external hubs.
	 *
	 * Likewise, not all root hubs will pass wakeup events upstream,
	 * to wake up the whole system.  So don't assume root hub and
	 * controller capabilities are identical.
	 */

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	case DeviceRequest | USB_REQ_GET_STATUS:
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		tbuf [0] = (device_may_wakeup(&hcd->self.root_hub->dev)
					<< USB_DEVICE_REMOTE_WAKEUP)
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				| (1 << USB_DEVICE_SELF_POWERED);
		tbuf [1] = 0;
		len = 2;
		break;
	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
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			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
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		else
			goto error;
		break;
	case DeviceOutRequest | USB_REQ_SET_FEATURE:
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		if (device_can_wakeup(&hcd->self.root_hub->dev)
				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
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		else
			goto error;
		break;
	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
		tbuf [0] = 1;
		len = 1;
			/* FALLTHROUGH */
	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
		break;
	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
		switch (wValue & 0xff00) {
		case USB_DT_DEVICE << 8:
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			switch (hcd->speed) {
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			case HCD_USB3:
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				bufp = usb3_rh_dev_descriptor;
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				break;
			case HCD_USB2:
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				bufp = usb2_rh_dev_descriptor;
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				break;
			case HCD_USB11:
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				bufp = usb11_rh_dev_descriptor;
535 536
				break;
			default:
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				goto error;
538
			}
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			len = 18;
540 541
			if (hcd->has_tt)
				patch_protocol = 1;
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			break;
		case USB_DT_CONFIG << 8:
544
			switch (hcd->speed) {
545
			case HCD_USB3:
546 547
				bufp = ss_rh_config_descriptor;
				len = sizeof ss_rh_config_descriptor;
548 549
				break;
			case HCD_USB2:
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				bufp = hs_rh_config_descriptor;
				len = sizeof hs_rh_config_descriptor;
552 553
				break;
			case HCD_USB11:
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				bufp = fs_rh_config_descriptor;
				len = sizeof fs_rh_config_descriptor;
556 557 558
				break;
			default:
				goto error;
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			}
560
			if (device_can_wakeup(&hcd->self.root_hub->dev))
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				patch_wakeup = 1;
			break;
		case USB_DT_STRING << 8:
564 565 566 567
			if ((wValue & 0xff) < 4)
				urb->actual_length = rh_string(wValue & 0xff,
						hcd, ubuf, wLength);
			else /* unsupported IDs --> "protocol stall" */
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				goto error;
			break;
570 571
		case USB_DT_BOS << 8:
			goto nongeneric;
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		default:
			goto error;
		}
		break;
	case DeviceRequest | USB_REQ_GET_INTERFACE:
		tbuf [0] = 0;
		len = 1;
			/* FALLTHROUGH */
	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
		break;
	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
		// wValue == urb->dev->devaddr
		dev_dbg (hcd->self.controller, "root hub device address %d\n",
			wValue);
		break;

	/* INTERFACE REQUESTS (no defined feature/status flags) */

	/* ENDPOINT REQUESTS */

	case EndpointRequest | USB_REQ_GET_STATUS:
		// ENDPOINT_HALT flag
		tbuf [0] = 0;
		tbuf [1] = 0;
		len = 2;
			/* FALLTHROUGH */
	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
	case EndpointOutRequest | USB_REQ_SET_FEATURE:
		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
		break;

	/* CLASS REQUESTS (and errors) */

	default:
606
nongeneric:
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		/* non-generic request */
608 609 610 611 612 613 614 615
		switch (typeReq) {
		case GetHubStatus:
		case GetPortStatus:
			len = 4;
			break;
		case GetHubDescriptor:
			len = sizeof (struct usb_hub_descriptor);
			break;
616 617 618
		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
			/* len is returned by hub_control */
			break;
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		}
620 621 622
		status = hcd->driver->hub_control (hcd,
			typeReq, wValue, wIndex,
			tbuf, wLength);
623 624 625 626

		if (typeReq == GetHubDescriptor)
			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
				(struct usb_hub_descriptor *)tbuf);
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		break;
error:
		/* "protocol stall" on error */
		status = -EPIPE;
	}

633
	if (status < 0) {
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		len = 0;
		if (status != -EPIPE) {
			dev_dbg (hcd->self.controller,
				"CTRL: TypeReq=0x%x val=0x%x "
				"idx=0x%x len=%d ==> %d\n",
				typeReq, wValue, wIndex,
640
				wLength, status);
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		}
642 643 644 645
	} else if (status > 0) {
		/* hub_control may return the length of data copied. */
		len = status;
		status = 0;
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	}
	if (len) {
		if (urb->transfer_buffer_length < len)
			len = urb->transfer_buffer_length;
		urb->actual_length = len;
		// always USB_DIR_IN, toward host
		memcpy (ubuf, bufp, len);

		/* report whether RH hardware supports remote wakeup */
		if (patch_wakeup &&
				len > offsetof (struct usb_config_descriptor,
						bmAttributes))
			((struct usb_config_descriptor *)ubuf)->bmAttributes
				|= USB_CONFIG_ATT_WAKEUP;
660 661 662 663 664 665

		/* report whether RH hardware has an integrated TT */
		if (patch_protocol &&
				len > offsetof(struct usb_device_descriptor,
						bDeviceProtocol))
			((struct usb_device_descriptor *) ubuf)->
666
				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
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	}

	/* any errors get returned through the urb completion */
670
	spin_lock_irq(&hcd_root_hub_lock);
671
	usb_hcd_unlink_urb_from_ep(hcd, urb);
672 673 674 675 676 677

	/* This peculiar use of spinlocks echoes what real HC drivers do.
	 * Avoiding calls to local_irq_disable/enable makes the code
	 * RT-friendly.
	 */
	spin_unlock(&hcd_root_hub_lock);
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	usb_hcd_giveback_urb(hcd, urb, status);
679 680 681
	spin_lock(&hcd_root_hub_lock);

	spin_unlock_irq(&hcd_root_hub_lock);
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	return 0;
}

/*-------------------------------------------------------------------------*/

/*
688 689 690
 * Root Hub interrupt transfers are polled using a timer if the
 * driver requests it; otherwise the driver is responsible for
 * calling usb_hcd_poll_rh_status() when an event occurs.
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 *
692 693
 * Completions are called in_interrupt(), but they may or may not
 * be in_irq().
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 */
695 696 697 698 699
void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
{
	struct urb	*urb;
	int		length;
	unsigned long	flags;
700
	char		buffer[6];	/* Any root hubs with > 31 ports? */
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702
	if (unlikely(!hcd->rh_pollable))
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		return;
704 705
	if (!hcd->uses_new_polling && !hcd->status_urb)
		return;
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707 708
	length = hcd->driver->hub_status_data(hcd, buffer);
	if (length > 0) {
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710
		/* try to complete the status urb */
711
		spin_lock_irqsave(&hcd_root_hub_lock, flags);
712 713
		urb = hcd->status_urb;
		if (urb) {
714
			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
715 716 717
			hcd->status_urb = NULL;
			urb->actual_length = length;
			memcpy(urb->transfer_buffer, buffer, length);
718

719
			usb_hcd_unlink_urb_from_ep(hcd, urb);
720
			spin_unlock(&hcd_root_hub_lock);
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			usb_hcd_giveback_urb(hcd, urb, 0);
722
			spin_lock(&hcd_root_hub_lock);
723
		} else {
724
			length = 0;
725
			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
726
		}
727
		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
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	}

730
	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
731 732
	 * exceed that limit if HZ is 100. The math is more clunky than
	 * maybe expected, this is to make sure that all timers for USB devices
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	 * fire at the same time to give the CPU a break in between */
734
	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
735
			(length == 0 && hcd->status_urb != NULL))
736
		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
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}
738
EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
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/* timer callback */
741 742 743 744 745 746
static void rh_timer_func (unsigned long _hcd)
{
	usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
}

/*-------------------------------------------------------------------------*/
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748
static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
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{
750
	int		retval;
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	unsigned long	flags;
752
	unsigned	len = 1 + (urb->dev->maxchild / 8);
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754
	spin_lock_irqsave (&hcd_root_hub_lock, flags);
755
	if (hcd->status_urb || urb->transfer_buffer_length < len) {
756 757
		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
		retval = -EINVAL;
758 759
		goto done;
	}
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761 762 763
	retval = usb_hcd_link_urb_to_ep(hcd, urb);
	if (retval)
		goto done;
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765 766 767 768 769 770
	hcd->status_urb = urb;
	urb->hcpriv = hcd;	/* indicate it's queued */
	if (!hcd->uses_new_polling)
		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));

	/* If a status change has already occurred, report it ASAP */
771
	else if (HCD_POLL_PENDING(hcd))
772 773 774
		mod_timer(&hcd->rh_timer, jiffies);
	retval = 0;
 done:
775 776
	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
	return retval;
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}

static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
{
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	if (usb_endpoint_xfer_int(&urb->ep->desc))
782
		return rh_queue_status (hcd, urb);
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	if (usb_endpoint_xfer_control(&urb->ep->desc))
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		return rh_call_control (hcd, urb);
785
	return -EINVAL;
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}

/*-------------------------------------------------------------------------*/

790 791
/* Unlinks of root-hub control URBs are legal, but they don't do anything
 * since these URBs always execute synchronously.
792
 */
793
static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
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{
795
	unsigned long	flags;
796
	int		rc;
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798
	spin_lock_irqsave(&hcd_root_hub_lock, flags);
799 800 801 802
	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
	if (rc)
		goto done;

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	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
804
		;	/* Do nothing */
805 806 807

	} else {				/* Status URB */
		if (!hcd->uses_new_polling)
808
			del_timer (&hcd->rh_timer);
809 810
		if (urb == hcd->status_urb) {
			hcd->status_urb = NULL;
811
			usb_hcd_unlink_urb_from_ep(hcd, urb);
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813
			spin_unlock(&hcd_root_hub_lock);
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			usb_hcd_giveback_urb(hcd, urb, status);
815 816 817
			spin_lock(&hcd_root_hub_lock);
		}
	}
818
 done:
819
	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
820
	return rc;
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}

823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882


/*
 * Show & store the current value of authorized_default
 */
static ssize_t usb_host_authorized_default_show(struct device *dev,
						struct device_attribute *attr,
						char *buf)
{
	struct usb_device *rh_usb_dev = to_usb_device(dev);
	struct usb_bus *usb_bus = rh_usb_dev->bus;
	struct usb_hcd *usb_hcd;

	if (usb_bus == NULL)	/* FIXME: not sure if this case is possible */
		return -ENODEV;
	usb_hcd = bus_to_hcd(usb_bus);
	return snprintf(buf, PAGE_SIZE, "%u\n", usb_hcd->authorized_default);
}

static ssize_t usb_host_authorized_default_store(struct device *dev,
						 struct device_attribute *attr,
						 const char *buf, size_t size)
{
	ssize_t result;
	unsigned val;
	struct usb_device *rh_usb_dev = to_usb_device(dev);
	struct usb_bus *usb_bus = rh_usb_dev->bus;
	struct usb_hcd *usb_hcd;

	if (usb_bus == NULL)	/* FIXME: not sure if this case is possible */
		return -ENODEV;
	usb_hcd = bus_to_hcd(usb_bus);
	result = sscanf(buf, "%u\n", &val);
	if (result == 1) {
		usb_hcd->authorized_default = val? 1 : 0;
		result = size;
	}
	else
		result = -EINVAL;
	return result;
}

static DEVICE_ATTR(authorized_default, 0644,
	    usb_host_authorized_default_show,
	    usb_host_authorized_default_store);


/* Group all the USB bus attributes */
static struct attribute *usb_bus_attrs[] = {
		&dev_attr_authorized_default.attr,
		NULL,
};

static struct attribute_group usb_bus_attr_group = {
	.name = NULL,	/* we want them in the same directory */
	.attrs = usb_bus_attrs,
};



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/*-------------------------------------------------------------------------*/

/**
 * usb_bus_init - shared initialization code
 * @bus: the bus structure being initialized
 *
 * This code is used to initialize a usb_bus structure, memory for which is
 * separately managed.
 */
static void usb_bus_init (struct usb_bus *bus)
{
	memset (&bus->devmap, 0, sizeof(struct usb_devmap));

	bus->devnum_next = 1;

	bus->root_hub = NULL;
	bus->busnum = -1;
	bus->bandwidth_allocated = 0;
	bus->bandwidth_int_reqs  = 0;
	bus->bandwidth_isoc_reqs = 0;

	INIT_LIST_HEAD (&bus->bus_list);
}

/*-------------------------------------------------------------------------*/

/**
 * usb_register_bus - registers the USB host controller with the usb core
 * @bus: pointer to the bus to register
 * Context: !in_interrupt()
 *
 * Assigns a bus number, and links the controller into usbcore data
 * structures so that it can be seen by scanning the bus list.
 */
static int usb_register_bus(struct usb_bus *bus)
{
919
	int result = -E2BIG;
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	int busnum;

922
	mutex_lock(&usb_bus_list_lock);
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923
	busnum = find_next_zero_bit (busmap.busmap, USB_MAXBUS, 1);
924
	if (busnum >= USB_MAXBUS) {
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925
		printk (KERN_ERR "%s: too many buses\n", usbcore_name);
926
		goto error_find_busnum;
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927
	}
928 929
	set_bit (busnum, busmap.busmap);
	bus->busnum = busnum;
930

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	/* Add it to the local list of buses */
	list_add (&bus->bus_list, &usb_bus_list);
933
	mutex_unlock(&usb_bus_list_lock);
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935
	usb_notify_add_bus(bus);
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936

937 938
	dev_info (bus->controller, "new USB bus registered, assigned bus "
		  "number %d\n", bus->busnum);
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939
	return 0;
940 941 942 943

error_find_busnum:
	mutex_unlock(&usb_bus_list_lock);
	return result;
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}

/**
 * usb_deregister_bus - deregisters the USB host controller
 * @bus: pointer to the bus to deregister
 * Context: !in_interrupt()
 *
 * Recycles the bus number, and unlinks the controller from usbcore data
 * structures so that it won't be seen by scanning the bus list.
 */
static void usb_deregister_bus (struct usb_bus *bus)
{
	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);

	/*
	 * NOTE: make sure that all the devices are removed by the
	 * controller code, as well as having it call this when cleaning
	 * itself up
	 */
963
	mutex_lock(&usb_bus_list_lock);
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	list_del (&bus->bus_list);
965
	mutex_unlock(&usb_bus_list_lock);
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966

967
	usb_notify_remove_bus(bus);
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	clear_bit (bus->busnum, busmap.busmap);
}

/**
973
 * register_root_hub - called by usb_add_hcd() to register a root hub
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 * @hcd: host controller for this root hub
 *
976
 * This function registers the root hub with the USB subsystem.  It sets up
977 978 979
 * the device properly in the device tree and then calls usb_new_device()
 * to register the usb device.  It also assigns the root hub's USB address
 * (always 1).
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 */
981
static int register_root_hub(struct usb_hcd *hcd)
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{
	struct device *parent_dev = hcd->self.controller;
984
	struct usb_device *usb_dev = hcd->self.root_hub;
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	const int devnum = 1;
	int retval;

	usb_dev->devnum = devnum;
	usb_dev->bus->devnum_next = devnum + 1;
	memset (&usb_dev->bus->devmap.devicemap, 0,
			sizeof usb_dev->bus->devmap.devicemap);
	set_bit (devnum, usb_dev->bus->devmap.devicemap);
	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);

995
	mutex_lock(&usb_bus_list_lock);
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997
	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
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	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
	if (retval != sizeof usb_dev->descriptor) {
1000
		mutex_unlock(&usb_bus_list_lock);
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		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1002
				dev_name(&usb_dev->dev), retval);
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1003 1004
		return (retval < 0) ? retval : -EMSGSIZE;
	}
1005 1006 1007 1008 1009 1010 1011 1012 1013
	if (usb_dev->speed == USB_SPEED_SUPER) {
		retval = usb_get_bos_descriptor(usb_dev);
		if (retval < 0) {
			mutex_unlock(&usb_bus_list_lock);
			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
					dev_name(&usb_dev->dev), retval);
			return retval;
		}
	}
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	retval = usb_new_device (usb_dev);
	if (retval) {
		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1018
				dev_name(&usb_dev->dev), retval);
1019
	} else {
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1020 1021 1022 1023 1024
		spin_lock_irq (&hcd_root_hub_lock);
		hcd->rh_registered = 1;
		spin_unlock_irq (&hcd_root_hub_lock);

		/* Did the HC die before the root hub was registered? */
1025
		if (HCD_DEAD(hcd))
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1026 1027
			usb_hc_died (hcd);	/* This time clean up */
	}
1028
	mutex_unlock(&usb_bus_list_lock);
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1029 1030 1031 1032

	return retval;
}

1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075
/*
 * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
 * @bus: the bus which the root hub belongs to
 * @portnum: the port which is being resumed
 *
 * HCDs should call this function when they know that a resume signal is
 * being sent to a root-hub port.  The root hub will be prevented from
 * going into autosuspend until usb_hcd_end_port_resume() is called.
 *
 * The bus's private lock must be held by the caller.
 */
void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
{
	unsigned bit = 1 << portnum;

	if (!(bus->resuming_ports & bit)) {
		bus->resuming_ports |= bit;
		pm_runtime_get_noresume(&bus->root_hub->dev);
	}
}
EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);

/*
 * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
 * @bus: the bus which the root hub belongs to
 * @portnum: the port which is being resumed
 *
 * HCDs should call this function when they know that a resume signal has
 * stopped being sent to a root-hub port.  The root hub will be allowed to
 * autosuspend again.
 *
 * The bus's private lock must be held by the caller.
 */
void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
{
	unsigned bit = 1 << portnum;

	if (bus->resuming_ports & bit) {
		bus->resuming_ports &= ~bit;
		pm_runtime_put_noidle(&bus->root_hub->dev);
	}
}
EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
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1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113

/*-------------------------------------------------------------------------*/

/**
 * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
 * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
 * @is_input: true iff the transaction sends data to the host
 * @isoc: true for isochronous transactions, false for interrupt ones
 * @bytecount: how many bytes in the transaction.
 *
 * Returns approximate bus time in nanoseconds for a periodic transaction.
 * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
 * scheduled in software, this function is only used for such scheduling.
 */
long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
{
	unsigned long	tmp;

	switch (speed) {
	case USB_SPEED_LOW: 	/* INTR only */
		if (is_input) {
			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
			return (64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
		} else {
			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
			return (64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
		}
	case USB_SPEED_FULL:	/* ISOC or INTR */
		if (isoc) {
			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
			return (((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp);
		} else {
			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
			return (9107L + BW_HOST_DELAY + tmp);
		}
	case USB_SPEED_HIGH:	/* ISOC or INTR */
		// FIXME adjust for input vs output
		if (isoc)
1114
			tmp = HS_NSECS_ISO (bytecount);
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1115
		else
1116
			tmp = HS_NSECS (bytecount);
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		return tmp;
	default:
		pr_debug ("%s: bogus device speed!\n", usbcore_name);
		return -1;
	}
}
1123
EXPORT_SYMBOL_GPL(usb_calc_bus_time);
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/*-------------------------------------------------------------------------*/

/*
 * Generic HC operations.
 */

/*-------------------------------------------------------------------------*/

1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149
/**
 * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
 * @hcd: host controller to which @urb was submitted
 * @urb: URB being submitted
 *
 * Host controller drivers should call this routine in their enqueue()
 * method.  The HCD's private spinlock must be held and interrupts must
 * be disabled.  The actions carried out here are required for URB
 * submission, as well as for endpoint shutdown and for usb_kill_urb.
 *
 * Returns 0 for no error, otherwise a negative error code (in which case
 * the enqueue() method must fail).  If no error occurs but enqueue() fails
 * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
 * the private spinlock and returning.
 */
int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
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1150
{
1151
	int		rc = 0;
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1152

1153
	spin_lock(&hcd_urb_list_lock);
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1154

1155
	/* Check that the URB isn't being killed */
1156
	if (unlikely(atomic_read(&urb->reject))) {
1157 1158
		rc = -EPERM;
		goto done;
1159
	}
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1160

1161 1162 1163 1164
	if (unlikely(!urb->ep->enabled)) {
		rc = -ENOENT;
		goto done;
	}
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1165

1166 1167 1168 1169 1170
	if (unlikely(!urb->dev->can_submit)) {
		rc = -EHOSTUNREACH;
		goto done;
	}

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1171
	/*
1172 1173
	 * Check the host controller's state and add the URB to the
	 * endpoint's queue.
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1174
	 */
1175
	if (HCD_RH_RUNNING(hcd)) {
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1176
		urb->unlinked = 0;
1177
		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1178
	} else {
1179 1180
		rc = -ESHUTDOWN;
		goto done;
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1181
	}
1182
 done:
1183
	spin_unlock(&hcd_urb_list_lock);
1184 1185
	return rc;
}
1186
EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1187

1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207
/**
 * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
 * @hcd: host controller to which @urb was submitted
 * @urb: URB being checked for unlinkability
 * @status: error code to store in @urb if the unlink succeeds
 *
 * Host controller drivers should call this routine in their dequeue()
 * method.  The HCD's private spinlock must be held and interrupts must
 * be disabled.  The actions carried out here are required for making
 * sure than an unlink is valid.
 *
 * Returns 0 for no error, otherwise a negative error code (in which case
 * the dequeue() method must fail).  The possible error codes are:
 *
 *	-EIDRM: @urb was not submitted or has already completed.
 *		The completion function may not have been called yet.
 *
 *	-EBUSY: @urb has already been unlinked.
 */
int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1208 1209 1210 1211 1212 1213 1214 1215 1216
		int status)
{
	struct list_head	*tmp;

	/* insist the urb is still queued */
	list_for_each(tmp, &urb->ep->urb_list) {
		if (tmp == &urb->urb_list)
			break;
	}
1217 1218
	if (tmp != &urb->urb_list)
		return -EIDRM;
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1219

1220 1221
	/* Any status except -EINPROGRESS means something already started to
	 * unlink this URB from the hardware.  So there's no more work to do.
L
Linus Torvalds 已提交
1222
	 */
A
Alan Stern 已提交
1223
	if (urb->unlinked)
1224
		return -EBUSY;
A
Alan Stern 已提交
1225
	urb->unlinked = status;
1226
	return 0;
1227
}
1228
EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1229

1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240
/**
 * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
 * @hcd: host controller to which @urb was submitted
 * @urb: URB being unlinked
 *
 * Host controller drivers should call this routine before calling
 * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
 * interrupts must be disabled.  The actions carried out here are required
 * for URB completion.
 */
void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1241 1242
{
	/* clear all state linking urb to this dev (and hcd) */
1243
	spin_lock(&hcd_urb_list_lock);
1244
	list_del_init(&urb->urb_list);
1245
	spin_unlock(&hcd_urb_list_lock);
1246
}
1247
EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1248

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1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287
/*
 * Some usb host controllers can only perform dma using a small SRAM area.
 * The usb core itself is however optimized for host controllers that can dma
 * using regular system memory - like pci devices doing bus mastering.
 *
 * To support host controllers with limited dma capabilites we provide dma
 * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
 * For this to work properly the host controller code must first use the
 * function dma_declare_coherent_memory() to point out which memory area
 * that should be used for dma allocations.
 *
 * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
 * dma using dma_alloc_coherent() which in turn allocates from the memory
 * area pointed out with dma_declare_coherent_memory().
 *
 * So, to summarize...
 *
 * - We need "local" memory, canonical example being
 *   a small SRAM on a discrete controller being the
 *   only memory that the controller can read ...
 *   (a) "normal" kernel memory is no good, and
 *   (b) there's not enough to share
 *
 * - The only *portable* hook for such stuff in the
 *   DMA framework is dma_declare_coherent_memory()
 *
 * - So we use that, even though the primary requirement
 *   is that the memory be "local" (hence addressible
 *   by that device), not "coherent".
 *
 */

static int hcd_alloc_coherent(struct usb_bus *bus,
			      gfp_t mem_flags, dma_addr_t *dma_handle,
			      void **vaddr_handle, size_t size,
			      enum dma_data_direction dir)
{
	unsigned char *vaddr;

1288 1289 1290 1291 1292
	if (*vaddr_handle == NULL) {
		WARN_ON_ONCE(1);
		return -EFAULT;
	}

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1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332
	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
				 mem_flags, dma_handle);
	if (!vaddr)
		return -ENOMEM;

	/*
	 * Store the virtual address of the buffer at the end
	 * of the allocated dma buffer. The size of the buffer
	 * may be uneven so use unaligned functions instead
	 * of just rounding up. It makes sense to optimize for
	 * memory footprint over access speed since the amount
	 * of memory available for dma may be limited.
	 */
	put_unaligned((unsigned long)*vaddr_handle,
		      (unsigned long *)(vaddr + size));

	if (dir == DMA_TO_DEVICE)
		memcpy(vaddr, *vaddr_handle, size);

	*vaddr_handle = vaddr;
	return 0;
}

static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
			      void **vaddr_handle, size_t size,
			      enum dma_data_direction dir)
{
	unsigned char *vaddr = *vaddr_handle;

	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));

	if (dir == DMA_FROM_DEVICE)
		memcpy(vaddr, *vaddr_handle, size);

	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);

	*vaddr_handle = vaddr;
	*dma_handle = 0;
}

1333
void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346
{
	if (urb->transfer_flags & URB_SETUP_MAP_SINGLE)
		dma_unmap_single(hcd->self.controller,
				urb->setup_dma,
				sizeof(struct usb_ctrlrequest),
				DMA_TO_DEVICE);
	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
		hcd_free_coherent(urb->dev->bus,
				&urb->setup_dma,
				(void **) &urb->setup_packet,
				sizeof(struct usb_ctrlrequest),
				DMA_TO_DEVICE);

1347 1348 1349
	/* Make it safe to call this routine more than once */
	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
}
1350
EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1351

1352 1353 1354 1355 1356 1357 1358 1359
static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
{
	if (hcd->driver->unmap_urb_for_dma)
		hcd->driver->unmap_urb_for_dma(hcd, urb);
	else
		usb_hcd_unmap_urb_for_dma(hcd, urb);
}

1360
void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1361 1362 1363
{
	enum dma_data_direction dir;

1364
	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1365

1366 1367 1368
	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
	if (urb->transfer_flags & URB_DMA_MAP_SG)
		dma_unmap_sg(hcd->self.controller,
1369
				urb->sg,
1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389
				urb->num_sgs,
				dir);
	else if (urb->transfer_flags & URB_DMA_MAP_PAGE)
		dma_unmap_page(hcd->self.controller,
				urb->transfer_dma,
				urb->transfer_buffer_length,
				dir);
	else if (urb->transfer_flags & URB_DMA_MAP_SINGLE)
		dma_unmap_single(hcd->self.controller,
				urb->transfer_dma,
				urb->transfer_buffer_length,
				dir);
	else if (urb->transfer_flags & URB_MAP_LOCAL)
		hcd_free_coherent(urb->dev->bus,
				&urb->transfer_dma,
				&urb->transfer_buffer,
				urb->transfer_buffer_length,
				dir);

	/* Make it safe to call this routine more than once */
1390
	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1391 1392
			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
}
1393
EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1394

M
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1395 1396
static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
			   gfp_t mem_flags)
1397 1398 1399 1400 1401 1402 1403 1404 1405
{
	if (hcd->driver->map_urb_for_dma)
		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
	else
		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
}

int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
			    gfp_t mem_flags)
1406
{
M
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1407 1408 1409
	enum dma_data_direction dir;
	int ret = 0;

1410 1411
	/* Map the URB's buffers for DMA access.
	 * Lower level HCD code should use *_dma exclusively,
1412 1413
	 * unless it uses pio or talks to another transport,
	 * or uses the provided scatter gather list for bulk.
L
Linus Torvalds 已提交
1414
	 */
M
Magnus Damm 已提交
1415

A
Alan Stern 已提交
1416
	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1417 1418
		if (hcd->self.uses_pio_for_control)
			return ret;
1419
		if (hcd->self.uses_dma) {
M
Magnus Damm 已提交
1420
			urb->setup_dma = dma_map_single(
L
Linus Torvalds 已提交
1421 1422
					hcd->self.controller,
					urb->setup_packet,
M
Magnus Damm 已提交
1423
					sizeof(struct usb_ctrlrequest),
L
Linus Torvalds 已提交
1424
					DMA_TO_DEVICE);
1425 1426 1427
			if (dma_mapping_error(hcd->self.controller,
						urb->setup_dma))
				return -EAGAIN;
1428
			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1429
		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
M
Magnus Damm 已提交
1430 1431 1432 1433 1434 1435
			ret = hcd_alloc_coherent(
					urb->dev->bus, mem_flags,
					&urb->setup_dma,
					(void **)&urb->setup_packet,
					sizeof(struct usb_ctrlrequest),
					DMA_TO_DEVICE);
1436 1437 1438
			if (ret)
				return ret;
			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1439
		}
M
Magnus Damm 已提交
1440 1441 1442
	}

	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1443
	if (urb->transfer_buffer_length != 0
M
Magnus Damm 已提交
1444
	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1445
		if (hcd->self.uses_dma) {
1446
			if (urb->num_sgs) {
1447 1448 1449 1450 1451 1452 1453 1454 1455
				int n;

				/* We don't support sg for isoc transfers ! */
				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
					WARN_ON(1);
					return -EINVAL;
				}

				n = dma_map_sg(
1456
						hcd->self.controller,
1457
						urb->sg,
1458 1459 1460 1461 1462 1463
						urb->num_sgs,
						dir);
				if (n <= 0)
					ret = -EAGAIN;
				else
					urb->transfer_flags |= URB_DMA_MAP_SG;
1464 1465
				urb->num_mapped_sgs = n;
				if (n != urb->num_sgs)
1466 1467 1468
					urb->transfer_flags |=
							URB_DMA_SG_COMBINED;
			} else if (urb->sg) {
1469
				struct scatterlist *sg = urb->sg;
1470 1471 1472 1473 1474 1475 1476
				urb->transfer_dma = dma_map_page(
						hcd->self.controller,
						sg_page(sg),
						sg->offset,
						urb->transfer_buffer_length,
						dir);
				if (dma_mapping_error(hcd->self.controller,
1477
						urb->transfer_dma))
1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492
					ret = -EAGAIN;
				else
					urb->transfer_flags |= URB_DMA_MAP_PAGE;
			} else {
				urb->transfer_dma = dma_map_single(
						hcd->self.controller,
						urb->transfer_buffer,
						urb->transfer_buffer_length,
						dir);
				if (dma_mapping_error(hcd->self.controller,
						urb->transfer_dma))
					ret = -EAGAIN;
				else
					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
			}
1493
		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
M
Magnus Damm 已提交
1494 1495 1496 1497 1498 1499
			ret = hcd_alloc_coherent(
					urb->dev->bus, mem_flags,
					&urb->transfer_dma,
					&urb->transfer_buffer,
					urb->transfer_buffer_length,
					dir);
1500 1501
			if (ret == 0)
				urb->transfer_flags |= URB_MAP_LOCAL;
M
Magnus Damm 已提交
1502
		}
1503 1504
		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
				URB_SETUP_MAP_LOCAL)))
1505
			usb_hcd_unmap_urb_for_dma(hcd, urb);
L
Linus Torvalds 已提交
1506
	}
M
Magnus Damm 已提交
1507
	return ret;
1508
}
1509
EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
L
Linus Torvalds 已提交
1510

1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528
/*-------------------------------------------------------------------------*/

/* may be called in any context with a valid urb->dev usecount
 * caller surrenders "ownership" of urb
 * expects usb_submit_urb() to have sanity checked and conditioned all
 * inputs in the urb
 */
int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
{
	int			status;
	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);

	/* increment urb's reference count as part of giving it to the HCD
	 * (which will control it).  HCD guarantees that it either returns
	 * an error or calls giveback(), but not both.
	 */
	usb_get_urb(urb);
	atomic_inc(&urb->use_count);
1529
	atomic_inc(&urb->dev->urbnum);
1530 1531 1532 1533 1534 1535 1536 1537 1538
	usbmon_urb_submit(&hcd->self, urb);

	/* NOTE requirements on root-hub callers (usbfs and the hub
	 * driver, for now):  URBs' urb->transfer_buffer must be
	 * valid and usb_buffer_{sync,unmap}() not be needed, since
	 * they could clobber root hub response data.  Also, control
	 * URBs must be submitted in process context with interrupts
	 * enabled.
	 */
M
Magnus Damm 已提交
1539

1540
	if (is_root_hub(urb->dev)) {
1541
		status = rh_urb_enqueue(hcd, urb);
1542 1543 1544 1545 1546
	} else {
		status = map_urb_for_dma(hcd, urb, mem_flags);
		if (likely(status == 0)) {
			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
			if (unlikely(status))
1547
				unmap_urb_for_dma(hcd, urb);
1548 1549
		}
	}
1550 1551

	if (unlikely(status)) {
L
Linus Torvalds 已提交
1552
		usbmon_urb_submit_error(&hcd->self, urb, status);
A
Alan Stern 已提交
1553
		urb->hcpriv = NULL;
1554 1555
		INIT_LIST_HEAD(&urb->urb_list);
		atomic_dec(&urb->use_count);
1556
		atomic_dec(&urb->dev->urbnum);
1557
		if (atomic_read(&urb->reject))
1558 1559
			wake_up(&usb_kill_urb_queue);
		usb_put_urb(urb);
L
Linus Torvalds 已提交
1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570
	}
	return status;
}

/*-------------------------------------------------------------------------*/

/* this makes the hcd giveback() the urb more quickly, by kicking it
 * off hardware queues (which may take a while) and returning it as
 * soon as practical.  we've already set up the urb's return status,
 * but we can't know if the callback completed already.
 */
1571
static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
L
Linus Torvalds 已提交
1572 1573 1574
{
	int		value;

1575
	if (is_root_hub(urb->dev))
1576
		value = usb_rh_urb_dequeue(hcd, urb, status);
L
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1577 1578 1579 1580 1581
	else {

		/* The only reason an HCD might fail this call is if
		 * it has not yet fully queued the urb to begin with.
		 * Such failures should be harmless. */
1582
		value = hcd->driver->urb_dequeue(hcd, urb, status);
L
Linus Torvalds 已提交
1583 1584 1585 1586 1587 1588 1589 1590 1591 1592
	}
	return value;
}

/*
 * called in any context
 *
 * caller guarantees urb won't be recycled till both unlink()
 * and the urb's completion function return
 */
A
Alan Stern 已提交
1593
int usb_hcd_unlink_urb (struct urb *urb, int status)
L
Linus Torvalds 已提交
1594
{
1595
	struct usb_hcd		*hcd;
1596 1597
	int			retval = -EIDRM;
	unsigned long		flags;
L
Linus Torvalds 已提交
1598

1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614
	/* Prevent the device and bus from going away while
	 * the unlink is carried out.  If they are already gone
	 * then urb->use_count must be 0, since disconnected
	 * devices can't have any active URBs.
	 */
	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
	if (atomic_read(&urb->use_count) > 0) {
		retval = 0;
		usb_get_dev(urb->dev);
	}
	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
	if (retval == 0) {
		hcd = bus_to_hcd(urb->dev->bus);
		retval = unlink1(hcd, urb, status);
		usb_put_dev(urb->dev);
	}
L
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1615 1616 1617

	if (retval == 0)
		retval = -EINPROGRESS;
1618
	else if (retval != -EIDRM && retval != -EBUSY)
1619 1620
		dev_dbg(&urb->dev->dev, "hcd_unlink_urb %p fail %d\n",
				urb, retval);
L
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1621 1622 1623 1624 1625
	return retval;
}

/*-------------------------------------------------------------------------*/

A
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1626 1627 1628 1629
/**
 * usb_hcd_giveback_urb - return URB from HCD to device driver
 * @hcd: host controller returning the URB
 * @urb: urb being returned to the USB device driver.
A
Alan Stern 已提交
1630
 * @status: completion status code for the URB.
A
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1631 1632 1633 1634 1635 1636 1637
 * Context: in_interrupt()
 *
 * This hands the URB from HCD to its USB device driver, using its
 * completion function.  The HCD has freed all per-urb resources
 * (and is done using urb->hcpriv).  It also released all HCD locks;
 * the device driver won't cause problems if it frees, modifies,
 * or resubmits this URB.
A
Alan Stern 已提交
1638
 *
A
Alan Stern 已提交
1639
 * If @urb was unlinked, the value of @status will be overridden by
A
Alan Stern 已提交
1640 1641
 * @urb->unlinked.  Erroneous short transfers are detected in case
 * the HCD hasn't checked for them.
A
Alan Stern 已提交
1642
 */
A
Alan Stern 已提交
1643
void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
A
Alan Stern 已提交
1644
{
A
Alan Stern 已提交
1645
	urb->hcpriv = NULL;
A
Alan Stern 已提交
1646
	if (unlikely(urb->unlinked))
A
Alan Stern 已提交
1647
		status = urb->unlinked;
A
Alan Stern 已提交
1648
	else if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
A
Alan Stern 已提交
1649
			urb->actual_length < urb->transfer_buffer_length &&
A
Alan Stern 已提交
1650 1651
			!status))
		status = -EREMOTEIO;
A
Alan Stern 已提交
1652

1653
	unmap_urb_for_dma(hcd, urb);
A
Alan Stern 已提交
1654
	usbmon_urb_complete(&hcd->self, urb, status);
1655 1656
	usb_unanchor_urb(urb);

A
Alan Stern 已提交
1657
	/* pass ownership to the completion handler */
A
Alan Stern 已提交
1658
	urb->status = status;
A
Alan Stern 已提交
1659 1660
	urb->complete (urb);
	atomic_dec (&urb->use_count);
1661
	if (unlikely(atomic_read(&urb->reject)))
A
Alan Stern 已提交
1662 1663 1664
		wake_up (&usb_kill_urb_queue);
	usb_put_urb (urb);
}
1665
EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
A
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1666 1667 1668

/*-------------------------------------------------------------------------*/

1669 1670 1671
/* Cancel all URBs pending on this endpoint and wait for the endpoint's
 * queue to drain completely.  The caller must first insure that no more
 * URBs can be submitted for this endpoint.
L
Linus Torvalds 已提交
1672
 */
1673
void usb_hcd_flush_endpoint(struct usb_device *udev,
A
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1674
		struct usb_host_endpoint *ep)
L
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1675 1676 1677 1678
{
	struct usb_hcd		*hcd;
	struct urb		*urb;

1679 1680
	if (!ep)
		return;
1681
	might_sleep();
1682
	hcd = bus_to_hcd(udev->bus);
L
Linus Torvalds 已提交
1683

1684
	/* No more submits can occur */
1685
	spin_lock_irq(&hcd_urb_list_lock);
1686
rescan:
L
Linus Torvalds 已提交
1687
	list_for_each_entry (urb, &ep->urb_list, urb_list) {
A
Alan Stern 已提交
1688
		int	is_in;
L
Linus Torvalds 已提交
1689

A
Alan Stern 已提交
1690
		if (urb->unlinked)
L
Linus Torvalds 已提交
1691 1692
			continue;
		usb_get_urb (urb);
A
Alan Stern 已提交
1693
		is_in = usb_urb_dir_in(urb);
1694
		spin_unlock(&hcd_urb_list_lock);
L
Linus Torvalds 已提交
1695

1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715
		/* kick hcd */
		unlink1(hcd, urb, -ESHUTDOWN);
		dev_dbg (hcd->self.controller,
			"shutdown urb %p ep%d%s%s\n",
			urb, usb_endpoint_num(&ep->desc),
			is_in ? "in" : "out",
			({	char *s;

				 switch (usb_endpoint_type(&ep->desc)) {
				 case USB_ENDPOINT_XFER_CONTROL:
					s = ""; break;
				 case USB_ENDPOINT_XFER_BULK:
					s = "-bulk"; break;
				 case USB_ENDPOINT_XFER_INT:
					s = "-intr"; break;
				 default:
			 		s = "-iso"; break;
				};
				s;
			}));
L
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1716 1717 1718
		usb_put_urb (urb);

		/* list contents may have changed */
1719
		spin_lock(&hcd_urb_list_lock);
L
Linus Torvalds 已提交
1720 1721
		goto rescan;
	}
1722
	spin_unlock_irq(&hcd_urb_list_lock);
L
Linus Torvalds 已提交
1723

1724
	/* Wait until the endpoint queue is completely empty */
1725
	while (!list_empty (&ep->urb_list)) {
1726
		spin_lock_irq(&hcd_urb_list_lock);
1727 1728 1729 1730 1731 1732 1733 1734

		/* The list may have changed while we acquired the spinlock */
		urb = NULL;
		if (!list_empty (&ep->urb_list)) {
			urb = list_entry (ep->urb_list.prev, struct urb,
					urb_list);
			usb_get_urb (urb);
		}
1735
		spin_unlock_irq(&hcd_urb_list_lock);
1736 1737 1738 1739 1740 1741

		if (urb) {
			usb_kill_urb (urb);
			usb_put_urb (urb);
		}
	}
L
Linus Torvalds 已提交
1742 1743
}

1744
/**
1745 1746 1747
 * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
 *				the bus bandwidth
 * @udev: target &usb_device
1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763
 * @new_config: new configuration to install
 * @cur_alt: the current alternate interface setting
 * @new_alt: alternate interface setting that is being installed
 *
 * To change configurations, pass in the new configuration in new_config,
 * and pass NULL for cur_alt and new_alt.
 *
 * To reset a device's configuration (put the device in the ADDRESSED state),
 * pass in NULL for new_config, cur_alt, and new_alt.
 *
 * To change alternate interface settings, pass in NULL for new_config,
 * pass in the current alternate interface setting in cur_alt,
 * and pass in the new alternate interface setting in new_alt.
 *
 * Returns an error if the requested bandwidth change exceeds the
 * bus bandwidth or host controller internal resources.
1764
 */
1765
int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1766
		struct usb_host_config *new_config,
1767 1768
		struct usb_host_interface *cur_alt,
		struct usb_host_interface *new_alt)
1769 1770
{
	int num_intfs, i, j;
1771
	struct usb_host_interface *alt = NULL;
1772 1773 1774 1775 1776 1777 1778 1779 1780
	int ret = 0;
	struct usb_hcd *hcd;
	struct usb_host_endpoint *ep;

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

	/* Configuration is being removed - set configuration 0 */
1781
	if (!new_config && !cur_alt) {
1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817
		for (i = 1; i < 16; ++i) {
			ep = udev->ep_out[i];
			if (ep)
				hcd->driver->drop_endpoint(hcd, udev, ep);
			ep = udev->ep_in[i];
			if (ep)
				hcd->driver->drop_endpoint(hcd, udev, ep);
		}
		hcd->driver->check_bandwidth(hcd, udev);
		return 0;
	}
	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
	 * ok to exclude it.
	 */
	if (new_config) {
		num_intfs = new_config->desc.bNumInterfaces;
		/* Remove endpoints (except endpoint 0, which is always on the
		 * schedule) from the old config from the schedule
		 */
		for (i = 1; i < 16; ++i) {
			ep = udev->ep_out[i];
			if (ep) {
				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
				if (ret < 0)
					goto reset;
			}
			ep = udev->ep_in[i];
			if (ep) {
				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
				if (ret < 0)
					goto reset;
			}
		}
		for (i = 0; i < num_intfs; ++i) {
1818 1819 1820 1821 1822
			struct usb_host_interface *first_alt;
			int iface_num;

			first_alt = &new_config->intf_cache[i]->altsetting[0];
			iface_num = first_alt->desc.bInterfaceNumber;
1823
			/* Set up endpoints for alternate interface setting 0 */
1824
			alt = usb_find_alt_setting(new_config, iface_num, 0);
1825 1826
			if (!alt)
				/* No alt setting 0? Pick the first setting. */
1827
				alt = first_alt;
1828

1829 1830 1831 1832 1833 1834 1835
			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
				if (ret < 0)
					goto reset;
			}
		}
	}
1836
	if (cur_alt && new_alt) {
1837 1838 1839
		struct usb_interface *iface = usb_ifnum_to_if(udev,
				cur_alt->desc.bInterfaceNumber);

1840 1841
		if (!iface)
			return -EINVAL;
1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856
		if (iface->resetting_device) {
			/*
			 * The USB core just reset the device, so the xHCI host
			 * and the device will think alt setting 0 is installed.
			 * However, the USB core will pass in the alternate
			 * setting installed before the reset as cur_alt.  Dig
			 * out the alternate setting 0 structure, or the first
			 * alternate setting if a broken device doesn't have alt
			 * setting 0.
			 */
			cur_alt = usb_altnum_to_altsetting(iface, 0);
			if (!cur_alt)
				cur_alt = &iface->altsetting[0];
		}

1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871
		/* Drop all the endpoints in the current alt setting */
		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
			ret = hcd->driver->drop_endpoint(hcd, udev,
					&cur_alt->endpoint[i]);
			if (ret < 0)
				goto reset;
		}
		/* Add all the endpoints in the new alt setting */
		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
			ret = hcd->driver->add_endpoint(hcd, udev,
					&new_alt->endpoint[i]);
			if (ret < 0)
				goto reset;
		}
	}
1872 1873 1874 1875 1876 1877 1878
	ret = hcd->driver->check_bandwidth(hcd, udev);
reset:
	if (ret < 0)
		hcd->driver->reset_bandwidth(hcd, udev);
	return ret;
}

1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897
/* Disables the endpoint: synchronizes with the hcd to make sure all
 * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
 * have been called previously.  Use for set_configuration, set_interface,
 * driver removal, physical disconnect.
 *
 * example:  a qh stored in ep->hcpriv, holding state related to endpoint
 * type, maxpacket size, toggle, halt status, and scheduling.
 */
void usb_hcd_disable_endpoint(struct usb_device *udev,
		struct usb_host_endpoint *ep)
{
	struct usb_hcd		*hcd;

	might_sleep();
	hcd = bus_to_hcd(udev->bus);
	if (hcd->driver->endpoint_disable)
		hcd->driver->endpoint_disable(hcd, ep);
}

1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923
/**
 * usb_hcd_reset_endpoint - reset host endpoint state
 * @udev: USB device.
 * @ep:   the endpoint to reset.
 *
 * Resets any host endpoint state such as the toggle bit, sequence
 * number and current window.
 */
void usb_hcd_reset_endpoint(struct usb_device *udev,
			    struct usb_host_endpoint *ep)
{
	struct usb_hcd *hcd = bus_to_hcd(udev->bus);

	if (hcd->driver->endpoint_reset)
		hcd->driver->endpoint_reset(hcd, ep);
	else {
		int epnum = usb_endpoint_num(&ep->desc);
		int is_out = usb_endpoint_dir_out(&ep->desc);
		int is_control = usb_endpoint_xfer_control(&ep->desc);

		usb_settoggle(udev, epnum, is_out, 0);
		if (is_control)
			usb_settoggle(udev, epnum, !is_out, 0);
	}
}

1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 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 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985
/**
 * usb_alloc_streams - allocate bulk endpoint stream IDs.
 * @interface:		alternate setting that includes all endpoints.
 * @eps:		array of endpoints that need streams.
 * @num_eps:		number of endpoints in the array.
 * @num_streams:	number of streams to allocate.
 * @mem_flags:		flags hcd should use to allocate memory.
 *
 * Sets up a group of bulk endpoints to have num_streams stream IDs available.
 * Drivers may queue multiple transfers to different stream IDs, which may
 * complete in a different order than they were queued.
 */
int usb_alloc_streams(struct usb_interface *interface,
		struct usb_host_endpoint **eps, unsigned int num_eps,
		unsigned int num_streams, gfp_t mem_flags)
{
	struct usb_hcd *hcd;
	struct usb_device *dev;
	int i;

	dev = interface_to_usbdev(interface);
	hcd = bus_to_hcd(dev->bus);
	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
		return -EINVAL;
	if (dev->speed != USB_SPEED_SUPER)
		return -EINVAL;

	/* Streams only apply to bulk endpoints. */
	for (i = 0; i < num_eps; i++)
		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
			return -EINVAL;

	return hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
			num_streams, mem_flags);
}
EXPORT_SYMBOL_GPL(usb_alloc_streams);

/**
 * usb_free_streams - free bulk endpoint stream IDs.
 * @interface:	alternate setting that includes all endpoints.
 * @eps:	array of endpoints to remove streams from.
 * @num_eps:	number of endpoints in the array.
 * @mem_flags:	flags hcd should use to allocate memory.
 *
 * Reverts a group of bulk endpoints back to not using stream IDs.
 * Can fail if we are given bad arguments, or HCD is broken.
 */
void usb_free_streams(struct usb_interface *interface,
		struct usb_host_endpoint **eps, unsigned int num_eps,
		gfp_t mem_flags)
{
	struct usb_hcd *hcd;
	struct usb_device *dev;
	int i;

	dev = interface_to_usbdev(interface);
	hcd = bus_to_hcd(dev->bus);
	if (dev->speed != USB_SPEED_SUPER)
		return;

	/* Streams only apply to bulk endpoints. */
	for (i = 0; i < num_eps; i++)
1986
		if (!eps[i] || !usb_endpoint_xfer_bulk(&eps[i]->desc))
1987 1988 1989 1990 1991 1992
			return;

	hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
}
EXPORT_SYMBOL_GPL(usb_free_streams);

1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
/* Protect against drivers that try to unlink URBs after the device
 * is gone, by waiting until all unlinks for @udev are finished.
 * Since we don't currently track URBs by device, simply wait until
 * nothing is running in the locked region of usb_hcd_unlink_urb().
 */
void usb_hcd_synchronize_unlinks(struct usb_device *udev)
{
	spin_lock_irq(&hcd_urb_unlink_lock);
	spin_unlock_irq(&hcd_urb_unlink_lock);
}

L
Linus Torvalds 已提交
2004 2005
/*-------------------------------------------------------------------------*/

A
Alan Stern 已提交
2006 2007 2008 2009 2010
/* called in any context */
int usb_hcd_get_frame_number (struct usb_device *udev)
{
	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);

2011
	if (!HCD_RH_RUNNING(hcd))
A
Alan Stern 已提交
2012 2013 2014 2015 2016 2017
		return -ESHUTDOWN;
	return hcd->driver->get_frame_number (hcd);
}

/*-------------------------------------------------------------------------*/

2018
#ifdef	CONFIG_PM
L
Linus Torvalds 已提交
2019

A
Alan Stern 已提交
2020
int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
L
Linus Torvalds 已提交
2021
{
2022 2023 2024
	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
	int		status;
	int		old_state = hcd->state;
L
Linus Torvalds 已提交
2025

2026 2027 2028
	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
			rhdev->do_remote_wakeup);
2029 2030 2031 2032 2033
	if (HCD_DEAD(hcd)) {
		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
		return 0;
	}

2034 2035 2036
	if (!hcd->driver->bus_suspend) {
		status = -ENOENT;
	} else {
2037
		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2038 2039 2040 2041 2042
		hcd->state = HC_STATE_QUIESCING;
		status = hcd->driver->bus_suspend(hcd);
	}
	if (status == 0) {
		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2043
		hcd->state = HC_STATE_SUSPENDED;
2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055

		/* Did we race with a root-hub wakeup event? */
		if (rhdev->do_remote_wakeup) {
			char	buffer[6];

			status = hcd->driver->hub_status_data(hcd, buffer);
			if (status != 0) {
				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
				status = -EBUSY;
			}
		}
2056
	} else {
2057 2058 2059 2060 2061 2062
		spin_lock_irq(&hcd_root_hub_lock);
		if (!HCD_DEAD(hcd)) {
			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
			hcd->state = old_state;
		}
		spin_unlock_irq(&hcd_root_hub_lock);
2063
		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2064
				"suspend", status);
2065
	}
2066
	return status;
L
Linus Torvalds 已提交
2067 2068
}

A
Alan Stern 已提交
2069
int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
L
Linus Torvalds 已提交
2070
{
2071 2072
	struct usb_hcd	*hcd = container_of(rhdev->bus, struct usb_hcd, self);
	int		status;
2073
	int		old_state = hcd->state;
L
Linus Torvalds 已提交
2074

2075 2076
	dev_dbg(&rhdev->dev, "usb %sresume\n",
			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2077 2078 2079 2080
	if (HCD_DEAD(hcd)) {
		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
		return 0;
	}
2081
	if (!hcd->driver->bus_resume)
2082
		return -ENOENT;
2083
	if (HCD_RH_RUNNING(hcd))
2084
		return 0;
2085

2086
	hcd->state = HC_STATE_RESUMING;
2087
	status = hcd->driver->bus_resume(hcd);
2088
	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2089
	if (status == 0) {
A
Alan Stern 已提交
2090 2091 2092
		struct usb_device *udev;
		int port1;

2093 2094 2095 2096 2097 2098 2099 2100 2101
		spin_lock_irq(&hcd_root_hub_lock);
		if (!HCD_DEAD(hcd)) {
			usb_set_device_state(rhdev, rhdev->actconfig
					? USB_STATE_CONFIGURED
					: USB_STATE_ADDRESS);
			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
			hcd->state = HC_STATE_RUNNING;
		}
		spin_unlock_irq(&hcd_root_hub_lock);
A
Alan Stern 已提交
2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115

		/*
		 * Check whether any of the enabled ports on the root hub are
		 * unsuspended.  If they are then a TRSMRCY delay is needed
		 * (this is what the USB-2 spec calls a "global resume").
		 * Otherwise we can skip the delay.
		 */
		usb_hub_for_each_child(rhdev, port1, udev) {
			if (udev->state != USB_STATE_NOTATTACHED &&
					!udev->port_is_suspended) {
				usleep_range(10000, 11000);	/* TRSMRCY */
				break;
			}
		}
2116
	} else {
2117
		hcd->state = old_state;
2118
		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2119
				"resume", status);
2120 2121
		if (status != -ESHUTDOWN)
			usb_hc_died(hcd);
2122 2123
	}
	return status;
L
Linus Torvalds 已提交
2124 2125
}

2126 2127 2128 2129
#endif	/* CONFIG_PM */

#ifdef	CONFIG_USB_SUSPEND

2130 2131 2132 2133 2134 2135 2136
/* Workqueue routine for root-hub remote wakeup */
static void hcd_resume_work(struct work_struct *work)
{
	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
	struct usb_device *udev = hcd->self.root_hub;

	usb_lock_device(udev);
2137
	usb_remote_wakeup(udev);
2138 2139 2140
	usb_unlock_device(udev);
}

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2141 2142 2143 2144 2145 2146
/**
 * usb_hcd_resume_root_hub - called by HCD to resume its root hub 
 * @hcd: host controller for this root hub
 *
 * The USB host controller calls this function when its root hub is
 * suspended (with the remote wakeup feature enabled) and a remote
2147 2148
 * wakeup request is received.  The routine submits a workqueue request
 * to resume the root hub (that is, manage its downstream ports again).
L
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 */
void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
{
	unsigned long flags;

	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2155 2156
	if (hcd->rh_registered) {
		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2157
		queue_work(pm_wq, &hcd->wakeup_work);
2158
	}
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2159 2160
	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
}
2161
EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
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2162

2163
#endif	/* CONFIG_USB_SUSPEND */
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2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199

/*-------------------------------------------------------------------------*/

#ifdef	CONFIG_USB_OTG

/**
 * usb_bus_start_enum - start immediate enumeration (for OTG)
 * @bus: the bus (must use hcd framework)
 * @port_num: 1-based number of port; usually bus->otg_port
 * Context: in_interrupt()
 *
 * Starts enumeration, with an immediate reset followed later by
 * khubd identifying and possibly configuring the device.
 * This is needed by OTG controller drivers, where it helps meet
 * HNP protocol timing requirements for starting a port reset.
 */
int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
{
	struct usb_hcd		*hcd;
	int			status = -EOPNOTSUPP;

	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
	 * boards with root hubs hooked up to internal devices (instead of
	 * just the OTG port) may need more attention to resetting...
	 */
	hcd = container_of (bus, struct usb_hcd, self);
	if (port_num && hcd->driver->start_port_reset)
		status = hcd->driver->start_port_reset(hcd, port_num);

	/* run khubd shortly after (first) root port reset finishes;
	 * it may issue others, until at least 50 msecs have passed.
	 */
	if (status == 0)
		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
	return status;
}
2200
EXPORT_SYMBOL_GPL(usb_bus_start_enum);
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2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213

#endif

/*-------------------------------------------------------------------------*/

/**
 * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
 * @irq: the IRQ being raised
 * @__hcd: pointer to the HCD whose IRQ is being signaled
 *
 * If the controller isn't HALTed, calls the driver's irq handler.
 * Checks whether the controller is now dead.
 */
2214
irqreturn_t usb_hcd_irq (int irq, void *__hcd)
L
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2215 2216
{
	struct usb_hcd		*hcd = __hcd;
2217
	unsigned long		flags;
2218
	irqreturn_t		rc;
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2220 2221 2222 2223 2224 2225
	/* IRQF_DISABLED doesn't work correctly with shared IRQs
	 * when the first handler doesn't use it.  So let's just
	 * assume it's never used.
	 */
	local_irq_save(flags);

A
Alan Stern 已提交
2226
	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2227
		rc = IRQ_NONE;
A
Alan Stern 已提交
2228
	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2229
		rc = IRQ_NONE;
A
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2230
	else
2231 2232
		rc = IRQ_HANDLED;

2233
	local_irq_restore(flags);
2234
	return rc;
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2235
}
D
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2236
EXPORT_SYMBOL_GPL(usb_hcd_irq);
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2237 2238 2239 2240 2241 2242 2243 2244 2245

/*-------------------------------------------------------------------------*/

/**
 * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
 * @hcd: pointer to the HCD representing the controller
 *
 * This is called by bus glue to report a USB host controller that died
 * while operations may still have been pending.  It's called automatically
2246 2247 2248
 * by the PCI glue, so only glue for non-PCI busses should need to call it.
 *
 * Only call this function with the primary HCD.
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 */
void usb_hc_died (struct usb_hcd *hcd)
{
	unsigned long flags;

	dev_err (hcd->self.controller, "HC died; cleaning up\n");

	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2257 2258
	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
	set_bit(HCD_FLAG_DEAD, &hcd->flags);
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2259
	if (hcd->rh_registered) {
2260
		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
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2261 2262 2263 2264 2265 2266

		/* make khubd clean up old urbs and devices */
		usb_set_device_state (hcd->self.root_hub,
				USB_STATE_NOTATTACHED);
		usb_kick_khubd (hcd->self.root_hub);
	}
2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277
	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
		hcd = hcd->shared_hcd;
		if (hcd->rh_registered) {
			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);

			/* make khubd clean up old urbs and devices */
			usb_set_device_state(hcd->self.root_hub,
					USB_STATE_NOTATTACHED);
			usb_kick_khubd(hcd->self.root_hub);
		}
	}
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2278
	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2279
	/* Make sure that the other roothub is also deallocated. */
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2280 2281 2282 2283 2284 2285
}
EXPORT_SYMBOL_GPL (usb_hc_died);

/*-------------------------------------------------------------------------*/

/**
2286
 * usb_create_shared_hcd - create and initialize an HCD structure
L
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2287 2288 2289
 * @driver: HC driver that will use this hcd
 * @dev: device for this HC, stored in hcd->self.controller
 * @bus_name: value to store in hcd->self.bus_name
2290 2291
 * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
 *              PCI device.  Only allocate certain resources for the primary HCD
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 * Context: !in_interrupt()
 *
 * Allocate a struct usb_hcd, with extra space at the end for the
 * HC driver's private data.  Initialize the generic members of the
 * hcd structure.
 *
 * If memory is unavailable, returns NULL.
 */
2300 2301 2302
struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
		struct device *dev, const char *bus_name,
		struct usb_hcd *primary_hcd)
L
Linus Torvalds 已提交
2303 2304 2305
{
	struct usb_hcd *hcd;

2306
	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
L
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2307 2308 2309 2310
	if (!hcd) {
		dev_dbg (dev, "hcd alloc failed\n");
		return NULL;
	}
2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326
	if (primary_hcd == NULL) {
		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
				GFP_KERNEL);
		if (!hcd->bandwidth_mutex) {
			kfree(hcd);
			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
			return NULL;
		}
		mutex_init(hcd->bandwidth_mutex);
		dev_set_drvdata(dev, hcd);
	} else {
		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
		hcd->primary_hcd = primary_hcd;
		primary_hcd->primary_hcd = primary_hcd;
		hcd->shared_hcd = primary_hcd;
		primary_hcd->shared_hcd = hcd;
2327 2328
	}

2329
	kref_init(&hcd->kref);
L
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2330 2331 2332 2333

	usb_bus_init(&hcd->self);
	hcd->self.controller = dev;
	hcd->self.bus_name = bus_name;
2334
	hcd->self.uses_dma = (dev->dma_mask != NULL);
L
Linus Torvalds 已提交
2335 2336

	init_timer(&hcd->rh_timer);
2337 2338
	hcd->rh_timer.function = rh_timer_func;
	hcd->rh_timer.data = (unsigned long) hcd;
2339
#ifdef CONFIG_USB_SUSPEND
2340 2341
	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
#endif
L
Linus Torvalds 已提交
2342 2343

	hcd->driver = driver;
2344
	hcd->speed = driver->flags & HCD_MASK;
L
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2345 2346 2347 2348
	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
			"USB Host Controller";
	return hcd;
}
2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368
EXPORT_SYMBOL_GPL(usb_create_shared_hcd);

/**
 * usb_create_hcd - create and initialize an HCD structure
 * @driver: HC driver that will use this hcd
 * @dev: device for this HC, stored in hcd->self.controller
 * @bus_name: value to store in hcd->self.bus_name
 * Context: !in_interrupt()
 *
 * Allocate a struct usb_hcd, with extra space at the end for the
 * HC driver's private data.  Initialize the generic members of the
 * hcd structure.
 *
 * If memory is unavailable, returns NULL.
 */
struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
		struct device *dev, const char *bus_name)
{
	return usb_create_shared_hcd(driver, dev, bus_name, NULL);
}
2369
EXPORT_SYMBOL_GPL(usb_create_hcd);
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Linus Torvalds 已提交
2370

2371 2372 2373 2374 2375 2376 2377 2378 2379 2380
/*
 * Roothubs that share one PCI device must also share the bandwidth mutex.
 * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
 * deallocated.
 *
 * Make sure to only deallocate the bandwidth_mutex when the primary HCD is
 * freed.  When hcd_release() is called for the non-primary HCD, set the
 * primary_hcd's shared_hcd pointer to null (since the non-primary HCD will be
 * freed shortly).
 */
2381 2382 2383 2384
static void hcd_release (struct kref *kref)
{
	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);

2385 2386 2387 2388
	if (usb_hcd_is_primary_hcd(hcd))
		kfree(hcd->bandwidth_mutex);
	else
		hcd->shared_hcd->shared_hcd = NULL;
2389 2390 2391 2392 2393 2394 2395 2396 2397
	kfree(hcd);
}

struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
{
	if (hcd)
		kref_get (&hcd->kref);
	return hcd;
}
2398
EXPORT_SYMBOL_GPL(usb_get_hcd);
2399

L
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2400 2401
void usb_put_hcd (struct usb_hcd *hcd)
{
2402 2403
	if (hcd)
		kref_put (&hcd->kref, hcd_release);
L
Linus Torvalds 已提交
2404
}
2405
EXPORT_SYMBOL_GPL(usb_put_hcd);
L
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2406

2407 2408 2409 2410 2411 2412 2413 2414
int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
{
	if (!hcd->primary_hcd)
		return 1;
	return hcd == hcd->primary_hcd;
}
EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);

2415 2416 2417 2418 2419 2420
static int usb_hcd_request_irqs(struct usb_hcd *hcd,
		unsigned int irqnum, unsigned long irqflags)
{
	int retval;

	if (hcd->driver->irq) {
2421 2422 2423 2424 2425 2426 2427 2428

		/* IRQF_DISABLED doesn't work as advertised when used together
		 * with IRQF_SHARED. As usb_hcd_irq() will always disable
		 * interrupts we can remove it here.
		 */
		if (irqflags & IRQF_SHARED)
			irqflags &= ~IRQF_DISABLED;

2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444
		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
				hcd->driver->description, hcd->self.busnum);
		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
				hcd->irq_descr, hcd);
		if (retval != 0) {
			dev_err(hcd->self.controller,
					"request interrupt %d failed\n",
					irqnum);
			return retval;
		}
		hcd->irq = irqnum;
		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
				(hcd->driver->flags & HCD_MEMORY) ?
					"io mem" : "io base",
					(unsigned long long)hcd->rsrc_start);
	} else {
2445
		hcd->irq = 0;
2446 2447 2448 2449 2450 2451 2452 2453 2454
		if (hcd->rsrc_start)
			dev_info(hcd->self.controller, "%s 0x%08llx\n",
					(hcd->driver->flags & HCD_MEMORY) ?
					"io mem" : "io base",
					(unsigned long long)hcd->rsrc_start);
	}
	return 0;
}

L
Linus Torvalds 已提交
2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467
/**
 * usb_add_hcd - finish generic HCD structure initialization and register
 * @hcd: the usb_hcd structure to initialize
 * @irqnum: Interrupt line to allocate
 * @irqflags: Interrupt type flags
 *
 * Finish the remaining parts of generic HCD initialization: allocate the
 * buffers of consistent memory, register the bus, request the IRQ line,
 * and call the driver's reset() and start() routines.
 */
int usb_add_hcd(struct usb_hcd *hcd,
		unsigned int irqnum, unsigned long irqflags)
{
2468 2469
	int retval;
	struct usb_device *rhdev;
L
Linus Torvalds 已提交
2470 2471 2472

	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);

2473 2474 2475 2476 2477
	/* Keep old behaviour if authorized_default is not in [0, 1]. */
	if (authorized_default < 0 || authorized_default > 1)
		hcd->authorized_default = hcd->wireless? 0 : 1;
	else
		hcd->authorized_default = authorized_default;
2478 2479
	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);

2480 2481 2482 2483
	/* HC is in reset state, but accessible.  Now do the one-time init,
	 * bottom up so that hcds can customize the root hubs before khubd
	 * starts talking to them.  (Note, bus id is assigned early too.)
	 */
L
Linus Torvalds 已提交
2484 2485 2486 2487 2488 2489
	if ((retval = hcd_buffer_create(hcd)) != 0) {
		dev_dbg(hcd->self.controller, "pool alloc failed\n");
		return retval;
	}

	if ((retval = usb_register_bus(&hcd->self)) < 0)
2490
		goto err_register_bus;
L
Linus Torvalds 已提交
2491

2492 2493 2494 2495 2496
	if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
		dev_err(hcd->self.controller, "unable to allocate root hub\n");
		retval = -ENOMEM;
		goto err_allocate_root_hub;
	}
2497
	hcd->self.root_hub = rhdev;
2498

2499
	switch (hcd->speed) {
2500 2501 2502 2503 2504 2505 2506 2507 2508 2509
	case HCD_USB11:
		rhdev->speed = USB_SPEED_FULL;
		break;
	case HCD_USB2:
		rhdev->speed = USB_SPEED_HIGH;
		break;
	case HCD_USB3:
		rhdev->speed = USB_SPEED_SUPER;
		break;
	default:
2510
		retval = -EINVAL;
2511
		goto err_set_rh_speed;
2512
	}
2513

2514 2515 2516 2517
	/* wakeup flag init defaults to "everything works" for root hubs,
	 * but drivers can override it in reset() if needed, along with
	 * recording the overall controller's system wakeup capability.
	 */
2518
	device_set_wakeup_capable(&rhdev->dev, 1);
2519

2520 2521 2522 2523 2524 2525
	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
	 * registered.  But since the controller can die at any time,
	 * let's initialize the flag before touching the hardware.
	 */
	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);

2526 2527 2528 2529 2530 2531 2532
	/* "reset" is misnamed; its role is now one-time init. the controller
	 * should already have been reset (and boot firmware kicked off etc).
	 */
	if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
		dev_err(hcd->self.controller, "can't setup\n");
		goto err_hcd_driver_setup;
	}
2533
	hcd->rh_pollable = 1;
2534

2535 2536 2537
	/* NOTE: root hub and controller capabilities may not be the same */
	if (device_can_wakeup(hcd->self.controller)
			&& device_can_wakeup(&hcd->self.root_hub->dev))
2538 2539
		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");

2540 2541 2542 2543
	/* enable irqs just before we start the controller,
	 * if the BIOS provides legacy PCI irqs.
	 */
	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2544 2545 2546 2547
		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
		if (retval)
			goto err_request_irq;
	}
L
Linus Torvalds 已提交
2548

2549
	hcd->state = HC_STATE_RUNNING;
2550 2551
	retval = hcd->driver->start(hcd);
	if (retval < 0) {
L
Linus Torvalds 已提交
2552
		dev_err(hcd->self.controller, "startup error %d\n", retval);
2553
		goto err_hcd_driver_start;
L
Linus Torvalds 已提交
2554 2555
	}

2556 2557
	/* starting here, usbcore will pay attention to this root hub */
	if ((retval = register_root_hub(hcd)) != 0)
2558 2559
		goto err_register_root_hub;

2560 2561 2562 2563 2564 2565
	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
	if (retval < 0) {
		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
		       retval);
		goto error_create_attr_group;
	}
2566
	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2567
		usb_hcd_poll_rh_status(hcd);
2568 2569 2570 2571 2572 2573 2574

	/*
	 * Host controllers don't generate their own wakeup requests;
	 * they only forward requests from the root hub.  Therefore
	 * controllers should always be enabled for remote wakeup.
	 */
	device_wakeup_enable(hcd->self.controller);
L
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2575 2576
	return retval;

2577
error_create_attr_group:
2578
	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2579 2580 2581 2582 2583 2584 2585 2586 2587
	if (HC_IS_RUNNING(hcd->state))
		hcd->state = HC_STATE_QUIESCING;
	spin_lock_irq(&hcd_root_hub_lock);
	hcd->rh_registered = 0;
	spin_unlock_irq(&hcd_root_hub_lock);

#ifdef CONFIG_USB_SUSPEND
	cancel_work_sync(&hcd->wakeup_work);
#endif
2588
	mutex_lock(&usb_bus_list_lock);
2589
	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2590
	mutex_unlock(&usb_bus_list_lock);
2591
err_register_root_hub:
2592
	hcd->rh_pollable = 0;
2593
	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2594
	del_timer_sync(&hcd->rh_timer);
2595
	hcd->driver->stop(hcd);
2596
	hcd->state = HC_STATE_HALT;
2597
	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2598
	del_timer_sync(&hcd->rh_timer);
2599
err_hcd_driver_start:
2600
	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
L
Linus Torvalds 已提交
2601
		free_irq(irqnum, hcd);
2602 2603
err_request_irq:
err_hcd_driver_setup:
2604
err_set_rh_speed:
2605
	usb_put_dev(hcd->self.root_hub);
2606
err_allocate_root_hub:
L
Linus Torvalds 已提交
2607
	usb_deregister_bus(&hcd->self);
2608
err_register_bus:
L
Linus Torvalds 已提交
2609 2610 2611
	hcd_buffer_destroy(hcd);
	return retval;
} 
2612
EXPORT_SYMBOL_GPL(usb_add_hcd);
L
Linus Torvalds 已提交
2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623

/**
 * usb_remove_hcd - shutdown processing for generic HCDs
 * @hcd: the usb_hcd structure to remove
 * Context: !in_interrupt()
 *
 * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
 * invoking the HCD's stop() method.
 */
void usb_remove_hcd(struct usb_hcd *hcd)
{
2624 2625
	struct usb_device *rhdev = hcd->self.root_hub;

L
Linus Torvalds 已提交
2626 2627
	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);

2628 2629
	usb_get_dev(rhdev);
	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2630

2631
	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
L
Linus Torvalds 已提交
2632 2633 2634 2635 2636 2637 2638
	if (HC_IS_RUNNING (hcd->state))
		hcd->state = HC_STATE_QUIESCING;

	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
	spin_lock_irq (&hcd_root_hub_lock);
	hcd->rh_registered = 0;
	spin_unlock_irq (&hcd_root_hub_lock);
2639

2640
#ifdef CONFIG_USB_SUSPEND
2641
	cancel_work_sync(&hcd->wakeup_work);
2642 2643
#endif

2644
	mutex_lock(&usb_bus_list_lock);
2645
	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2646
	mutex_unlock(&usb_bus_list_lock);
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	/* Prevent any more root-hub status calls from the timer.
	 * The HCD might still restart the timer (if a port status change
	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
	 * the hub_status_data() callback.
	 */
	hcd->rh_pollable = 0;
2654
	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
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	del_timer_sync(&hcd->rh_timer);

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	hcd->driver->stop(hcd);
	hcd->state = HC_STATE_HALT;

2660
	/* In case the HCD restarted the timer, stop it again. */
2661
	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
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	del_timer_sync(&hcd->rh_timer);

2664
	if (usb_hcd_is_primary_hcd(hcd)) {
2665
		if (hcd->irq > 0)
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			free_irq(hcd->irq, hcd);
	}
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	usb_put_dev(hcd->self.root_hub);
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	usb_deregister_bus(&hcd->self);
	hcd_buffer_destroy(hcd);
}
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EXPORT_SYMBOL_GPL(usb_remove_hcd);
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void
usb_hcd_platform_shutdown(struct platform_device* dev)
{
	struct usb_hcd *hcd = platform_get_drvdata(dev);

	if (hcd->driver->shutdown)
		hcd->driver->shutdown(hcd);
}
2683
EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
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/*-------------------------------------------------------------------------*/

2687
#if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
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struct usb_mon_operations *mon_ops;

/*
 * The registration is unlocked.
 * We do it this way because we do not want to lock in hot paths.
 *
 * Notice that the code is minimally error-proof. Because usbmon needs
 * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
 */
 
int usb_mon_register (struct usb_mon_operations *ops)
{

	if (mon_ops)
		return -EBUSY;

	mon_ops = ops;
	mb();
	return 0;
}
EXPORT_SYMBOL_GPL (usb_mon_register);

void usb_mon_deregister (void)
{

	if (mon_ops == NULL) {
		printk(KERN_ERR "USB: monitor was not registered\n");
		return;
	}
	mon_ops = NULL;
	mb();
}
EXPORT_SYMBOL_GPL (usb_mon_deregister);

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#endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */