usb: gadget: add SuperSpeed support to the Gadget Framework

SuperSpeed USB has defined a new descriptor, called
the Binary Device Object Store (BOS) Descriptor. It
has also changed a bit the definition of SET_FEATURE
and GET_STATUS requests to add USB3-specific details.

This patch implements both changes to the Composite
Gadget Framework.

[ balbi@ti.com : slight changes to commit log
		 fixed a compile error on ARM ]
Signed-off-by: NTatyana Brokhman <tlinder@codeaurora.org>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/Kconfig

@@ -666,6 +666,12 @@ config USB_GADGET_DUALSPEED
 	bool
 	depends on USB_GADGET
 
+# Selected by UDC drivers that support super-speed opperation
+config USB_GADGET_SUPERSPEED
+	bool
+	depends on USB_GADGET
+	depends on USB_GADGET_DUALSPEED
+
 #
 # USB Gadget Drivers
 #

drivers/usb/gadget/composite.c

@@ -27,7 +27,7 @@
 #include <linux/utsname.h>
 
 #include <linux/usb/composite.h>
-
+#include <asm/unaligned.h>
 
 /*
  * The code in this file is utility code, used to build a gadget driver
@@ -128,6 +128,9 @@ int config_ep_by_speed(struct usb_gadget *g,
 	struct usb_endpoint_descriptor *chosen_desc = NULL;
 	struct usb_descriptor_header **speed_desc = NULL;
 
+	struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
+	int want_comp_desc = 0;
+
 	struct usb_descriptor_header **d_spd; /* cursor for speed desc */
 
 	if (!g || !f || !_ep)
@@ -135,6 +138,13 @@ int config_ep_by_speed(struct usb_gadget *g,
 
 	/* select desired speed */
 	switch (g->speed) {
+	case USB_SPEED_SUPER:
+		if (gadget_is_superspeed(g)) {
+			speed_desc = f->ss_descriptors;
+			want_comp_desc = 1;
+			break;
+		}
+		/* else: Fall trough */
 	case USB_SPEED_HIGH:
 		if (gadget_is_dualspeed(g)) {
 			speed_desc = f->hs_descriptors;
@@ -156,7 +166,36 @@ int config_ep_by_speed(struct usb_gadget *g,
 	/* commit results */
 	_ep->maxpacket = le16_to_cpu(chosen_desc->wMaxPacketSize);
 	_ep->desc = chosen_desc;
+	_ep->comp_desc = NULL;
+	_ep->maxburst = 0;
+	_ep->mult = 0;
+	if (!want_comp_desc)
+		return 0;
 
+	/*
+	 * Companion descriptor should follow EP descriptor
+	 * USB 3.0 spec, #9.6.7
+	 */
+	comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
+	if (!comp_desc ||
+	    (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
+		return -EIO;
+	_ep->comp_desc = comp_desc;
+	if (g->speed == USB_SPEED_SUPER) {
+		switch (usb_endpoint_type(_ep->desc)) {
+		case USB_ENDPOINT_XFER_BULK:
+		case USB_ENDPOINT_XFER_INT:
+			_ep->maxburst = comp_desc->bMaxBurst;
+			break;
+		case USB_ENDPOINT_XFER_ISOC:
+			/* mult: bits 1:0 of bmAttributes */
+			_ep->mult = comp_desc->bmAttributes & 0x3;
+			break;
+		default:
+			/* Do nothing for control endpoints */
+			break;
+		}
+	}
 	return 0;
 }
 
@@ -208,6 +247,8 @@ int usb_add_function(struct usb_configuration *config,
 		config->fullspeed = true;
 	if (!config->highspeed && function->hs_descriptors)
 		config->highspeed = true;
+	if (!config->superspeed && function->ss_descriptors)
+		config->superspeed = true;
 
 done:
 	if (value)
@@ -351,10 +392,17 @@ static int config_buf(struct usb_configuration *config,
 	list_for_each_entry(f, &config->functions, list) {
 		struct usb_descriptor_header **descriptors;
 
-		if (speed == USB_SPEED_HIGH)
+		switch (speed) {
+		case USB_SPEED_SUPER:
+			descriptors = f->ss_descriptors;
+			break;
+		case USB_SPEED_HIGH:
 			descriptors = f->hs_descriptors;
-		else
+			break;
+		default:
 			descriptors = f->descriptors;
+		}
+
 		if (!descriptors)
 			continue;
 		status = usb_descriptor_fillbuf(next, len,
@@ -377,9 +425,10 @@ static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 	u8				type = w_value >> 8;
 	enum usb_device_speed		speed = USB_SPEED_UNKNOWN;
 
-	if (gadget_is_dualspeed(gadget)) {
-		int			hs = 0;
-
+	if (gadget->speed == USB_SPEED_SUPER)
+		speed = gadget->speed;
+	else if (gadget_is_dualspeed(gadget)) {
+		int	hs = 0;
 		if (gadget->speed == USB_SPEED_HIGH)
 			hs = 1;
 		if (type == USB_DT_OTHER_SPEED_CONFIG)
@@ -393,13 +442,20 @@ static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
 	w_value &= 0xff;
 	list_for_each_entry(c, &cdev->configs, list) {
 		/* ignore configs that won't work at this speed */
-		if (speed == USB_SPEED_HIGH) {
+		switch (speed) {
+		case USB_SPEED_SUPER:
+			if (!c->superspeed)
+				continue;
+			break;
+		case USB_SPEED_HIGH:
 			if (!c->highspeed)
 				continue;
-		} else {
+			break;
+		default:
 			if (!c->fullspeed)
 				continue;
 		}
+
 		if (w_value == 0)
 			return config_buf(c, speed, cdev->req->buf, type);
 		w_value--;
@@ -413,16 +469,22 @@ static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 	struct usb_configuration	*c;
 	unsigned			count = 0;
 	int				hs = 0;
+	int				ss = 0;
 
 	if (gadget_is_dualspeed(gadget)) {
 		if (gadget->speed == USB_SPEED_HIGH)
 			hs = 1;
+		if (gadget->speed == USB_SPEED_SUPER)
+			ss = 1;
 		if (type == USB_DT_DEVICE_QUALIFIER)
 			hs = !hs;
 	}
 	list_for_each_entry(c, &cdev->configs, list) {
 		/* ignore configs that won't work at this speed */
-		if (hs) {
+		if (ss) {
+			if (!c->superspeed)
+				continue;
+		} else if (hs) {
 			if (!c->highspeed)
 				continue;
 		} else {
@@ -434,6 +496,71 @@ static int count_configs(struct usb_composite_dev *cdev, unsigned type)
 	return count;
 }
 
+/**
+ * bos_desc() - prepares the BOS descriptor.
+ * @cdev: pointer to usb_composite device to generate the bos
+ *	descriptor for
+ *
+ * This function generates the BOS (Binary Device Object)
+ * descriptor and its device capabilities descriptors. The BOS
+ * descriptor should be supported by a SuperSpeed device.
+ */
+static int bos_desc(struct usb_composite_dev *cdev)
+{
+	struct usb_ext_cap_descriptor	*usb_ext;
+	struct usb_ss_cap_descriptor	*ss_cap;
+	struct usb_dcd_config_params	dcd_config_params;
+	struct usb_bos_descriptor	*bos = cdev->req->buf;
+
+	bos->bLength = USB_DT_BOS_SIZE;
+	bos->bDescriptorType = USB_DT_BOS;
+
+	bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
+	bos->bNumDeviceCaps = 0;
+
+	/*
+	 * A SuperSpeed device shall include the USB2.0 extension descriptor
+	 * and shall support LPM when operating in USB2.0 HS mode.
+	 */
+	usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
+	bos->bNumDeviceCaps++;
+	le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
+	usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
+	usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
+	usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
+	usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT);
+
+	/*
+	 * The Superspeed USB Capability descriptor shall be implemented by all
+	 * SuperSpeed devices.
+	 */
+	ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
+	bos->bNumDeviceCaps++;
+	le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
+	ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
+	ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
+	ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
+	ss_cap->bmAttributes = 0; /* LTM is not supported yet */
+	ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
+				USB_FULL_SPEED_OPERATION |
+				USB_HIGH_SPEED_OPERATION |
+				USB_5GBPS_OPERATION);
+	ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
+
+	/* Get Controller configuration */
+	if (cdev->gadget->ops->get_config_params)
+		cdev->gadget->ops->get_config_params(&dcd_config_params);
+	else {
+		dcd_config_params.bU1devExitLat = USB_DEFULT_U1_DEV_EXIT_LAT;
+		dcd_config_params.bU2DevExitLat =
+			cpu_to_le16(USB_DEFULT_U2_DEV_EXIT_LAT);
+	}
+	ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
+	ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
+
+	return le16_to_cpu(bos->wTotalLength);
+}
+
 static void device_qual(struct usb_composite_dev *cdev)
 {
 	struct usb_qualifier_descriptor	*qual = cdev->req->buf;
@@ -477,20 +604,27 @@ static int set_config(struct usb_composite_dev *cdev,
 	unsigned		power = gadget_is_otg(gadget) ? 8 : 100;
 	int			tmp;
 
-	if (cdev->config)
-		reset_config(cdev);
-
 	if (number) {
 		list_for_each_entry(c, &cdev->configs, list) {
 			if (c->bConfigurationValue == number) {
+				/*
+				 * We disable the FDs of the previous
+				 * configuration only if the new configuration
+				 * is a valid one
+				 */
+				if (cdev->config)
+					reset_config(cdev);
 				result = 0;
 				break;
 			}
 		}
 		if (result < 0)
 			goto done;
-	} else
+	} else { /* Zero configuration value - need to reset the config */
+		if (cdev->config)
+			reset_config(cdev);
 		result = 0;
+	}
 
 	INFO(cdev, "%s speed config #%d: %s\n",
 		({ char *speed;
@@ -504,6 +638,9 @@ static int set_config(struct usb_composite_dev *cdev,
 		case USB_SPEED_HIGH:
 			speed = "high";
 			break;
+		case USB_SPEED_SUPER:
+			speed = "super";
+			break;
 		default:
 			speed = "?";
 			break;
@@ -528,10 +665,16 @@ static int set_config(struct usb_composite_dev *cdev,
 		 * function's setup callback instead of the current
 		 * configuration's setup callback.
 		 */
-		if (gadget->speed == USB_SPEED_HIGH)
+		switch (gadget->speed) {
+		case USB_SPEED_SUPER:
+			descriptors = f->ss_descriptors;
+			break;
+		case USB_SPEED_HIGH:
 			descriptors = f->hs_descriptors;
-		else
+			break;
+		default:
 			descriptors = f->descriptors;
+		}
 
 		for (; *descriptors; ++descriptors) {
 			struct usb_endpoint_descriptor *ep;
@@ -624,8 +767,9 @@ int usb_add_config(struct usb_composite_dev *cdev,
 	} else {
 		unsigned	i;
 
-		DBG(cdev, "cfg %d/%p speeds:%s%s\n",
+		DBG(cdev, "cfg %d/%p speeds:%s%s%s\n",
 			config->bConfigurationValue, config,
+			config->superspeed ? " super" : "",
 			config->highspeed ? " high" : "",
 			config->fullspeed
 				? (gadget_is_dualspeed(cdev->gadget)
@@ -904,6 +1048,7 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
 	struct usb_request		*req = cdev->req;
 	int				value = -EOPNOTSUPP;
+	int				status = 0;
 	u16				w_index = le16_to_cpu(ctrl->wIndex);
 	u8				intf = w_index & 0xFF;
 	u16				w_value = le16_to_cpu(ctrl->wValue);
@@ -931,18 +1076,29 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 		case USB_DT_DEVICE:
 			cdev->desc.bNumConfigurations =
 				count_configs(cdev, USB_DT_DEVICE);
+			cdev->desc.bMaxPacketSize0 =
+				cdev->gadget->ep0->maxpacket;
+			if (gadget_is_superspeed(gadget)) {
+				if (gadget->speed >= USB_SPEED_SUPER)
+					cdev->desc.bcdUSB = cpu_to_le16(0x0300);
+				else
+					cdev->desc.bcdUSB = cpu_to_le16(0x0210);
+			}
+
 			value = min(w_length, (u16) sizeof cdev->desc);
 			memcpy(req->buf, &cdev->desc, value);
 			break;
 		case USB_DT_DEVICE_QUALIFIER:
-			if (!gadget_is_dualspeed(gadget))
+			if (!gadget_is_dualspeed(gadget) ||
+			    gadget->speed >= USB_SPEED_SUPER)
 				break;
 			device_qual(cdev);
 			value = min_t(int, w_length,
 				sizeof(struct usb_qualifier_descriptor));
 			break;
 		case USB_DT_OTHER_SPEED_CONFIG:
-			if (!gadget_is_dualspeed(gadget))
+			if (!gadget_is_dualspeed(gadget) ||
+			    gadget->speed >= USB_SPEED_SUPER)
 				break;
 			/* FALLTHROUGH */
 		case USB_DT_CONFIG:
@@ -956,6 +1112,12 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 			if (value >= 0)
 				value = min(w_length, (u16) value);
 			break;
+		case USB_DT_BOS:
+			if (gadget_is_superspeed(gadget)) {
+				value = bos_desc(cdev);
+				value = min(w_length, (u16) value);
+			}
+			break;
 		}
 		break;
 
@@ -1023,6 +1185,61 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 		*((u8 *)req->buf) = value;
 		value = min(w_length, (u16) 1);
 		break;
+
+	/*
+	 * USB 3.0 additions:
+	 * Function driver should handle get_status request. If such cb
+	 * wasn't supplied we respond with default value = 0
+	 * Note: function driver should supply such cb only for the first
+	 * interface of the function
+	 */
+	case USB_REQ_GET_STATUS:
+		if (!gadget_is_superspeed(gadget))
+			goto unknown;
+		if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
+			goto unknown;
+		value = 2;	/* This is the length of the get_status reply */
+		put_unaligned_le16(0, req->buf);
+		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
+			break;
+		f = cdev->config->interface[intf];
+		if (!f)
+			break;
+		status = f->get_status ? f->get_status(f) : 0;
+		if (status < 0)
+			break;
+		put_unaligned_le16(status & 0x0000ffff, req->buf);
+		break;
+	/*
+	 * Function drivers should handle SetFeature/ClearFeature
+	 * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
+	 * only for the first interface of the function
+	 */
+	case USB_REQ_CLEAR_FEATURE:
+	case USB_REQ_SET_FEATURE:
+		if (!gadget_is_superspeed(gadget))
+			goto unknown;
+		if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
+			goto unknown;
+		switch (w_value) {
+		case USB_INTRF_FUNC_SUSPEND:
+			if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
+				break;
+			f = cdev->config->interface[intf];
+			if (!f)
+				break;
+			value = 0;
+			if (f->func_suspend)
+				value = f->func_suspend(f, w_index >> 8);
+			if (value < 0) {
+				ERROR(cdev,
+				      "func_suspend() returned error %d\n",
+				      value);
+				value = 0;
+			}
+			break;
+		}
+		break;
 	default:
 unknown:
 		VDBG(cdev,
@@ -1340,7 +1557,11 @@ composite_resume(struct usb_gadget *gadget)
 /*-------------------------------------------------------------------------*/
 
 static struct usb_gadget_driver composite_driver = {
+#ifdef CONFIG_USB_GADGET_SUPERSPEED
+	.speed		= USB_SPEED_SUPER,
+#else
 	.speed		= USB_SPEED_HIGH,
+#endif
 
 	.unbind		= composite_unbind,
 

drivers/usb/gadget/epautoconf.c

@@ -161,13 +161,13 @@ ep_matches (
 	max = 0x7ff & le16_to_cpu(desc->wMaxPacketSize);
 	switch (type) {
 	case USB_ENDPOINT_XFER_INT:
-		/* INT:  limit 64 bytes full speed, 1024 high speed */
+		/* INT:  limit 64 bytes full speed, 1024 high/super speed */
 		if (!gadget->is_dualspeed && max > 64)
 			return 0;
 		/* FALLTHROUGH */
 
 	case USB_ENDPOINT_XFER_ISOC:
-		/* ISO:  limit 1023 bytes full speed, 1024 high speed */
+		/* ISO:  limit 1023 bytes full speed, 1024 high/super speed */
 		if (ep->maxpacket < max)
 			return 0;
 		if (!gadget->is_dualspeed && max > 1023)
@@ -202,7 +202,7 @@ ep_matches (
 	}
 
 	/* report (variable) full speed bulk maxpacket */
-	if (USB_ENDPOINT_XFER_BULK == type) {
+	if ((USB_ENDPOINT_XFER_BULK == type) && !ep_comp) {
 		int size = ep->maxpacket;
 
 		/* min() doesn't work on bitfields with gcc-3.5 */

include/linux/usb/composite.h

@@ -59,6 +59,10 @@ struct usb_configuration;
  * @hs_descriptors: Table of high speed descriptors, using interface and
  *	string identifiers assigned during @bind().  If this pointer is null,
  *	the function will not be available at high speed.
+ * @ss_descriptors: Table of super speed descriptors, using interface and
+ *	string identifiers assigned during @bind(). If this
+ *	pointer is null after initiation, the function will not
+ *	be available at super speed.
  * @config: assigned when @usb_add_function() is called; this is the
  *	configuration with which this function is associated.
  * @bind: Before the gadget can register, all of its functions bind() to the
@@ -77,6 +81,10 @@ struct usb_configuration;
  * @setup: Used for interface-specific control requests.
  * @suspend: Notifies functions when the host stops sending USB traffic.
  * @resume: Notifies functions when the host restarts USB traffic.
+ * @get_status: Returns function status as a reply to
+ *	GetStatus() request when the recepient is Interface.
+ * @func_suspend: callback to be called when
+ *	SetFeature(FUNCTION_SUSPEND) is reseived
  *
  * A single USB function uses one or more interfaces, and should in most
  * cases support operation at both full and high speeds.  Each function is
@@ -106,6 +114,7 @@ struct usb_function {
 	struct usb_gadget_strings	**strings;
 	struct usb_descriptor_header	**descriptors;
 	struct usb_descriptor_header	**hs_descriptors;
+	struct usb_descriptor_header	**ss_descriptors;
 
 	struct usb_configuration	*config;
 
@@ -132,6 +141,10 @@ struct usb_function {
 	void			(*suspend)(struct usb_function *);
 	void			(*resume)(struct usb_function *);
 
+	/* USB 3.0 additions */
+	int			(*get_status)(struct usb_function *);
+	int			(*func_suspend)(struct usb_function *,
+						u8 suspend_opt);
 	/* private: */
 	/* internals */
 	struct list_head		list;
@@ -219,6 +232,7 @@ struct usb_configuration {
 	struct list_head	list;
 	struct list_head	functions;
 	u8			next_interface_id;
+	unsigned		superspeed:1;
 	unsigned		highspeed:1;
 	unsigned		fullspeed:1;
 	struct usb_function	*interface[MAX_CONFIG_INTERFACES];

include/linux/usb/gadget.h

@@ -136,6 +136,8 @@ struct usb_ep_ops {
  *      the endpoint descriptor used to configure the endpoint.
  * @max_streams: The maximum number of streams supported
  *	by this EP (0 - 16, actual number is 2^n)
+ * @mult: multiplier, 'mult' value for SS Isoc EPs
+ * @maxburst: the maximum number of bursts supported by this EP (for usb3)
  * @driver_data:for use by the gadget driver.
  * @address: used to identify the endpoint when finding descriptor that
  *	matches connection speed
@@ -156,6 +158,8 @@ struct usb_ep {
 	struct list_head	ep_list;
 	unsigned		maxpacket:16;
 	unsigned		max_streams:16;
+	unsigned		mult:2;
+	unsigned		maxburst:4;
 	u8			address;
 	const struct usb_endpoint_descriptor	*desc;
 	const struct usb_ss_ep_comp_descriptor	*comp_desc;
@@ -426,6 +430,14 @@ static inline void usb_ep_fifo_flush(struct usb_ep *ep)
 
 /*-------------------------------------------------------------------------*/
 
+struct usb_dcd_config_params {
+	__u8  bU1devExitLat;	/* U1 Device exit Latency */
+#define USB_DEFULT_U1_DEV_EXIT_LAT	0x01	/* Less then 1 microsec */
+	__le16 bU2DevExitLat;	/* U2 Device exit Latency */
+#define USB_DEFULT_U2_DEV_EXIT_LAT	0x1F4	/* Less then 500 microsec */
+};
+
+
 struct usb_gadget;
 struct usb_gadget_driver;
 
@@ -441,6 +453,7 @@ struct usb_gadget_ops {
 	int	(*pullup) (struct usb_gadget *, int is_on);
 	int	(*ioctl)(struct usb_gadget *,
 				unsigned code, unsigned long param);
+	void	(*get_config_params)(struct usb_dcd_config_params *);
 	int	(*start)(struct usb_gadget_driver *,
 			int (*bind)(struct usb_gadget *));
 	int	(*stop)(struct usb_gadget_driver *);
@@ -534,6 +547,24 @@ static inline int gadget_is_dualspeed(struct usb_gadget *g)
 #endif
 }
 
+/**
+ * gadget_is_superspeed() - return true if the hardware handles
+ * supperspeed
+ * @g: controller that might support supper speed
+ */
+static inline int gadget_is_superspeed(struct usb_gadget *g)
+{
+#ifdef CONFIG_USB_GADGET_SUPERSPEED
+	/*
+	 * runtime test would check "g->is_superspeed" ... that might be
+	 * useful to work around hardware bugs, but is mostly pointless
+	 */
+	return 1;
+#else
+	return 0;
+#endif
+}
+
 /**
  * gadget_is_otg - return true iff the hardware is OTG-ready
  * @g: controller that might have a Mini-AB connector