Commit b37d83a6 authored by Mathias Nyman's avatar Mathias Nyman Committed by Greg Kroah-Hartman
Browse files

usb: Parse the new USB 3.1 SuperSpeedPlus Isoc endpoint companion descriptor 



USB 3.1 devices can return a new SuperSpeedPlus isoc endpoint companion
descriptor for a isochronous endpoint that requires more than 48K bytes
per Service Interval.

The new descriptor immediately follows the old USB 3.0 SuperSpeed Endpoint
Companion and will provide a new BytesPerInterval value.

It is parsed and stored in struct usb_host_endpoint with the other endpoint
related descriptors, and should be used by USB3.1 capable hosts to reserve
bus time in the schedule.

Signed-off-by: default avatarMathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c8b1d897

drivers/usb/core/config.c

+31 −0
Original line number Diff line number Diff line
@@ -43,6 +43,27 @@ static int find_next_descriptor(unsigned char *buffer, int size, 
	return buffer - buffer0;

}



static void usb_parse_ssp_isoc_endpoint_companion(struct device *ddev,

		int cfgno, int inum, int asnum, struct usb_host_endpoint *ep,

		unsigned char *buffer, int size)

{

	struct usb_ssp_isoc_ep_comp_descriptor *desc;



	/*

	 * The SuperSpeedPlus Isoc endpoint companion descriptor immediately

	 * follows the SuperSpeed Endpoint Companion descriptor

	 */

	desc = (struct usb_ssp_isoc_ep_comp_descriptor *) buffer;

	if (desc->bDescriptorType != USB_DT_SSP_ISOC_ENDPOINT_COMP ||

	    size < USB_DT_SSP_ISOC_EP_COMP_SIZE) {

		dev_warn(ddev, "Invalid SuperSpeedPlus isoc endpoint companion"

			 "for config %d interface %d altsetting %d ep %d.\n",

			 cfgno, inum, asnum, ep->desc.bEndpointAddress);

		return;

	}

	memcpy(&ep->ssp_isoc_ep_comp, desc, USB_DT_SSP_ISOC_EP_COMP_SIZE);

}



static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno,

		int inum, int asnum, struct usb_host_endpoint *ep,

		unsigned char *buffer, int size)
@@ -54,6 +75,9 @@ static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno, 
	 * be the first thing immediately following the endpoint descriptor.

	 */

	desc = (struct usb_ss_ep_comp_descriptor *) buffer;

	buffer += desc->bLength;

	size -= desc->bLength;



	if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP ||

			size < USB_DT_SS_EP_COMP_SIZE) {

		dev_warn(ddev, "No SuperSpeed endpoint companion for config %d "
@@ -112,6 +136,7 @@ static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno, 
				cfgno, inum, asnum, ep->desc.bEndpointAddress);

		ep->ss_ep_comp.bmAttributes = 16;

	} else if (usb_endpoint_xfer_isoc(&ep->desc) &&

		   !USB_SS_SSP_ISOC_COMP(desc->bmAttributes) &&

		   USB_SS_MULT(desc->bmAttributes) > 3) {

		dev_warn(ddev, "Isoc endpoint has Mult of %d in "

				"config %d interface %d altsetting %d ep %d: "
@@ -121,6 +146,12 @@ static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno, 
		ep->ss_ep_comp.bmAttributes = 2;

	}



	/* Parse a possible SuperSpeedPlus isoc ep companion descriptor */

	if (usb_endpoint_xfer_isoc(&ep->desc) &&

	    USB_SS_SSP_ISOC_COMP(desc->bmAttributes))

		usb_parse_ssp_isoc_endpoint_companion(ddev, cfgno, inum, asnum,

							ep, buffer, size);



	if (usb_endpoint_xfer_isoc(&ep->desc))

		max_tx = (desc->bMaxBurst + 1) *

			(USB_SS_MULT(desc->bmAttributes)) *

include/linux/usb.h

+2 −0
Original line number Diff line number Diff line
@@ -50,6 +50,7 @@ struct ep_device; 
 * struct usb_host_endpoint - host-side endpoint descriptor and queue

 * @desc: descriptor for this endpoint, wMaxPacketSize in native byteorder

 * @ss_ep_comp: SuperSpeed companion descriptor for this endpoint

 * @ssp_isoc_ep_comp: SuperSpeedPlus isoc companion descriptor for this endpoint

 * @urb_list: urbs queued to this endpoint; maintained by usbcore

 * @hcpriv: for use by HCD; typically holds hardware dma queue head (QH)

 *	with one or more transfer descriptors (TDs) per urb
@@ -65,6 +66,7 @@ struct ep_device; 
struct usb_host_endpoint {

	struct usb_endpoint_descriptor		desc;

	struct usb_ss_ep_comp_descriptor	ss_ep_comp;

	struct usb_ssp_isoc_ep_comp_descriptor	ssp_isoc_ep_comp;

	struct list_head		urb_list;

	void				*hcpriv;

	struct ep_device		*ep_dev;	/* For sysfs info */

CRA Git | Maintained and supported by SUSTech CRA and CCSE