usb: gadget: composite: always set ep->mult to a sensible value (eaa496ff) · Commits · 戴 / test

ep->mult is supposed to be set to Isochronous and Interrupt Endapoint's multiplier value. This value is computed from different places depending on the link speed. If we're dealing with HighSpeed, then it's part of bits [12:11] of wMaxPacketSize. This case wasn't taken into consideration before. While at that, also make sure the ep->mult defaults to one so drivers can use it unconditionally and assume they'll never multiply ep->maxpacket to zero. Cc: <stable@vger.kernel.org> Signed-off-by:

Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/composite.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -201,7 +201,12 @@ ep_found:
		_ep->desc = chosen_desc;
		_ep->comp_desc = NULL;
		_ep->maxburst = 0;
		_ep->mult = 0;
		_ep->mult = 1;

		if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) \|\|
		usb_endpoint_xfer_int(_ep->desc)))
		_ep->mult = usb_endpoint_maxp_mult(_ep->desc);

		if (!want_comp_desc)
		return 0;

		@@ -218,7 +223,7 @@ ep_found:
		switch (usb_endpoint_type(_ep->desc)) {
		case USB_ENDPOINT_XFER_ISOC:
		/* mult: bits 1:0 of bmAttributes */
		_ep->mult = comp_desc->bmAttributes & 0x3;
		_ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
		case USB_ENDPOINT_XFER_BULK:
		case USB_ENDPOINT_XFER_INT:
		_ep->maxburst = comp_desc->bMaxBurst + 1;

drivers/usb/gadget/function/uvc_video.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -243,7 +243,7 @@ uvc_video_alloc_requests(struct uvc_video *video)

		req_size = video->ep->maxpacket
		* max_t(unsigned int, video->ep->maxburst, 1)
		* (video->ep->mult + 1);
		* (video->ep->mult);

		for (i = 0; i < UVC_NUM_REQUESTS; ++i) {
		video->req_buffer[i] = kmalloc(req_size, GFP_KERNEL);

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