usb: gadget: add streams support to the gadget framework

This patch defines necessary fields to support
streaming for USB3.0.

It implements a new function, called
usb_ep_autoconfig_ss(), to be used instead of the
existing usb_ep_autoconfig() when working in
SuperSpeed mode and there is a need to search for
an endpoint according to the number of required
streams.

[ balbi@ti.com : slight changes to commit log ]

Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Tatyana Brokhman <tlinder@codeaurora.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/epautoconf.c

@@ -63,13 +63,16 @@ static int
 ep_matches (
 	struct usb_gadget		*gadget,
 	struct usb_ep			*ep,
-	struct usb_endpoint_descriptor	*desc
+	struct usb_endpoint_descriptor	*desc,
+	struct usb_ss_ep_comp_descriptor *ep_comp
 )
 {
 	u8		type;
 	const char	*tmp;
 	u16		max;
 
+	int		num_req_streams = 0;
+
 	/* endpoint already claimed? */
 	if (NULL != ep->driver_data)
 		return 0;
@@ -128,6 +131,22 @@ ep_matches (
 		}
 	}
 
+	/*
+	 * Get the number of required streams from the EP companion
+	 * descriptor and see if the EP matches it
+	 */
+	if (usb_endpoint_xfer_bulk(desc)) {
+		if (ep_comp) {
+			num_req_streams = ep_comp->bmAttributes & 0x1f;
+			if (num_req_streams > ep->max_streams)
+				return 0;
+			/* Update the ep_comp descriptor if needed */
+			if (num_req_streams != ep->max_streams)
+				ep_comp->bmAttributes = ep->max_streams;
+		}
+
+	}
+
 	/*
 	 * If the protocol driver hasn't yet decided on wMaxPacketSize
 	 * and wants to know the maximum possible, provide the info.
@@ -208,7 +227,120 @@ find_ep (struct usb_gadget *gadget, const char *name)
 }
 
 /**
- * usb_ep_autoconfig - choose an endpoint matching the descriptor
+ * usb_ep_autoconfig_ss() - choose an endpoint matching the ep
+ * descriptor and ep companion descriptor
+ * @gadget: The device to which the endpoint must belong.
+ * @desc: Endpoint descriptor, with endpoint direction and transfer mode
+ *    initialized.  For periodic transfers, the maximum packet
+ *    size must also be initialized.  This is modified on
+ *    success.
+ * @ep_comp: Endpoint companion descriptor, with the required
+ *    number of streams. Will be modified when the chosen EP
+ *    supports a different number of streams.
+ *
+ * This routine replaces the usb_ep_autoconfig when needed
+ * superspeed enhancments. If such enhancemnets are required,
+ * the FD should call usb_ep_autoconfig_ss directly and provide
+ * the additional ep_comp parameter.
+ *
+ * By choosing an endpoint to use with the specified descriptor,
+ * this routine simplifies writing gadget drivers that work with
+ * multiple USB device controllers.  The endpoint would be
+ * passed later to usb_ep_enable(), along with some descriptor.
+ *
+ * That second descriptor won't always be the same as the first one.
+ * For example, isochronous endpoints can be autoconfigured for high
+ * bandwidth, and then used in several lower bandwidth altsettings.
+ * Also, high and full speed descriptors will be different.
+ *
+ * Be sure to examine and test the results of autoconfiguration
+ * on your hardware.  This code may not make the best choices
+ * about how to use the USB controller, and it can't know all
+ * the restrictions that may apply. Some combinations of driver
+ * and hardware won't be able to autoconfigure.
+ *
+ * On success, this returns an un-claimed usb_ep, and modifies the endpoint
+ * descriptor bEndpointAddress.  For bulk endpoints, the wMaxPacket value
+ * is initialized as if the endpoint were used at full speed and
+ * the bmAttribute field in the ep companion descriptor is
+ * updated with the assigned number of streams if it is
+ * different from the original value. To prevent the endpoint
+ * from being returned by a later autoconfig call, claim it by
+ * assigning ep->driver_data to some non-null value.
+ *
+ * On failure, this returns a null endpoint descriptor.
+ */
+struct usb_ep *usb_ep_autoconfig_ss(
+	struct usb_gadget		*gadget,
+	struct usb_endpoint_descriptor	*desc,
+	struct usb_ss_ep_comp_descriptor *ep_comp
+)
+{
+	struct usb_ep	*ep;
+	u8		type;
+
+	type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
+
+	/* First, apply chip-specific "best usage" knowledge.
+	 * This might make a good usb_gadget_ops hook ...
+	 */
+	if (gadget_is_net2280 (gadget) && type == USB_ENDPOINT_XFER_INT) {
+		/* ep-e, ep-f are PIO with only 64 byte fifos */
+		ep = find_ep (gadget, "ep-e");
+		if (ep && ep_matches(gadget, ep, desc, ep_comp))
+			return ep;
+		ep = find_ep (gadget, "ep-f");
+		if (ep && ep_matches(gadget, ep, desc, ep_comp))
+			return ep;
+
+	} else if (gadget_is_goku (gadget)) {
+		if (USB_ENDPOINT_XFER_INT == type) {
+			/* single buffering is enough */
+			ep = find_ep(gadget, "ep3-bulk");
+			if (ep && ep_matches(gadget, ep, desc, ep_comp))
+				return ep;
+		} else if (USB_ENDPOINT_XFER_BULK == type
+				&& (USB_DIR_IN & desc->bEndpointAddress)) {
+			/* DMA may be available */
+			ep = find_ep(gadget, "ep2-bulk");
+			if (ep && ep_matches(gadget, ep, desc,
+					      ep_comp))
+				return ep;
+		}
+
+#ifdef CONFIG_BLACKFIN
+	} else if (gadget_is_musbhdrc(gadget)) {
+		if ((USB_ENDPOINT_XFER_BULK == type) ||
+		    (USB_ENDPOINT_XFER_ISOC == type)) {
+			if (USB_DIR_IN & desc->bEndpointAddress)
+				ep = find_ep (gadget, "ep5in");
+			else
+				ep = find_ep (gadget, "ep6out");
+		} else if (USB_ENDPOINT_XFER_INT == type) {
+			if (USB_DIR_IN & desc->bEndpointAddress)
+				ep = find_ep(gadget, "ep1in");
+			else
+				ep = find_ep(gadget, "ep2out");
+		} else
+			ep = NULL;
+		if (ep && ep_matches(gadget, ep, desc, ep_comp))
+			return ep;
+#endif
+	}
+
+	/* Second, look at endpoints until an unclaimed one looks usable */
+	list_for_each_entry (ep, &gadget->ep_list, ep_list) {
+		if (ep_matches(gadget, ep, desc, ep_comp))
+			return ep;
+	}
+
+	/* Fail */
+	return NULL;
+}
+
+/**
+ * usb_ep_autoconfig() - choose an endpoint matching the
+ * descriptor
  * @gadget: The device to which the endpoint must belong.
  * @desc: Endpoint descriptor, with endpoint direction and transfer mode
  *	initialized.  For periodic transfers, the maximum packet
@@ -237,72 +369,15 @@ find_ep (struct usb_gadget *gadget, const char *name)
  *
  * On failure, this returns a null endpoint descriptor.
  */
-struct usb_ep *usb_ep_autoconfig (
+struct usb_ep *usb_ep_autoconfig(
 	struct usb_gadget		*gadget,
 	struct usb_endpoint_descriptor	*desc
 )
 {
-	struct usb_ep	*ep;
+	return usb_ep_autoconfig_ss(gadget, desc, NULL);
-	u8		type;
-
-	type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
-
-	/* First, apply chip-specific "best usage" knowledge.
-	 * This might make a good usb_gadget_ops hook ...
-	 */
-	if (gadget_is_net2280 (gadget) && type == USB_ENDPOINT_XFER_INT) {
-		/* ep-e, ep-f are PIO with only 64 byte fifos */
-		ep = find_ep (gadget, "ep-e");
-		if (ep && ep_matches (gadget, ep, desc))
-			return ep;
-		ep = find_ep (gadget, "ep-f");
-		if (ep && ep_matches (gadget, ep, desc))
-			return ep;
-
-	} else if (gadget_is_goku (gadget)) {
-		if (USB_ENDPOINT_XFER_INT == type) {
-			/* single buffering is enough */
-			ep = find_ep (gadget, "ep3-bulk");
-			if (ep && ep_matches (gadget, ep, desc))
-				return ep;
-		} else if (USB_ENDPOINT_XFER_BULK == type
-				&& (USB_DIR_IN & desc->bEndpointAddress)) {
-			/* DMA may be available */
-			ep = find_ep (gadget, "ep2-bulk");
-			if (ep && ep_matches (gadget, ep, desc))
-				return ep;
-		}
-
-#ifdef CONFIG_BLACKFIN
-	} else if (gadget_is_musbhdrc(gadget)) {
-		if ((USB_ENDPOINT_XFER_BULK == type) ||
-		    (USB_ENDPOINT_XFER_ISOC == type)) {
-			if (USB_DIR_IN & desc->bEndpointAddress)
-				ep = find_ep (gadget, "ep5in");
-			else
-				ep = find_ep (gadget, "ep6out");
-		} else if (USB_ENDPOINT_XFER_INT == type) {
-			if (USB_DIR_IN & desc->bEndpointAddress)
-				ep = find_ep(gadget, "ep1in");
-			else
-				ep = find_ep(gadget, "ep2out");
-		} else
-			ep = NULL;
-		if (ep && ep_matches (gadget, ep, desc))
-			return ep;
-#endif
-	}
-
-	/* Second, look at endpoints until an unclaimed one looks usable */
-	list_for_each_entry (ep, &gadget->ep_list, ep_list) {
-		if (ep_matches (gadget, ep, desc))
-			return ep;
-	}
-
-	/* Fail */
-	return NULL;
 }
 
+
 /**
  * usb_ep_autoconfig_reset - reset endpoint autoconfig state
  * @gadget: device for which autoconfig state will be reset

include/linux/usb/gadget.h

@@ -28,6 +28,7 @@ struct usb_ep;
  *	field, and the usb controller needs one, it is responsible
  *	for mapping and unmapping the buffer.
  * @length: Length of that data
+ * @stream_id: The stream id, when USB3.0 bulk streams are being used
  * @no_interrupt: If true, hints that no completion irq is needed.
  *	Helpful sometimes with deep request queues that are handled
  *	directly by DMA controllers.
@@ -82,6 +83,7 @@ struct usb_request {
 	unsigned		length;
 	dma_addr_t		dma;
 
+	unsigned		stream_id:16;
 	unsigned		no_interrupt:1;
 	unsigned		zero:1;
 	unsigned		short_not_ok:1;
@@ -132,11 +134,15 @@ struct usb_ep_ops {
  * @maxpacket:The maximum packet size used on this endpoint.  The initial
  *	value can sometimes be reduced (hardware allowing), according to
  *      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)
  * @driver_data:for use by the gadget driver.
  * @address: used to identify the endpoint when finding descriptor that
  *	matches connection speed
  * @desc: endpoint descriptor.  This pointer is set before the endpoint is
  *	enabled and remains valid until the endpoint is disabled.
+ * @comp_desc: In case of SuperSpeed support, this is the endpoint companion
+ *	descriptor that is used to configure the endpoint
  *
  * the bus controller driver lists all the general purpose endpoints in
  * gadget->ep_list.  the control endpoint (gadget->ep0) is not in that list,
@@ -149,8 +155,10 @@ struct usb_ep {
 	const struct usb_ep_ops	*ops;
 	struct list_head	ep_list;
 	unsigned		maxpacket:16;
+	unsigned		max_streams:16;
 	u8			address;
 	const struct usb_endpoint_descriptor	*desc;
+	const struct usb_ss_ep_comp_descriptor	*comp_desc;
 };
 
 /*-------------------------------------------------------------------------*/
@@ -895,6 +903,11 @@ static inline void usb_free_descriptors(struct usb_descriptor_header **v)
 extern struct usb_ep *usb_ep_autoconfig(struct usb_gadget *,
 			struct usb_endpoint_descriptor *);
 
+
+extern struct usb_ep *usb_ep_autoconfig_ss(struct usb_gadget *,
+			struct usb_endpoint_descriptor *,
+			struct usb_ss_ep_comp_descriptor *);
+
 extern void usb_ep_autoconfig_reset(struct usb_gadget *);
 
 #endif /* __LINUX_USB_GADGET_H */