FAILED: patch "[PATCH] usb: gadget: composite: always set ep->mult to a sensible" failed to apply to 4.4-stable tree

PATCH [email protected] 1 participant 1 message Jan 3, 2017

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Stable branch USB USB webcam gadget

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2017-01-03 20:01 UTC #0 lore raw

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

Quoted 1 line

From eaa496ffaaf19591fe471a36cef366146eeb9153 Mon Sep 17 00:00:00 2001

From: Felipe Balbi <[email protected]>
Date: Wed, 28 Sep 2016 12:33:31 +0300
Subject: [PATCH] usb: gadget: composite: always set ep->mult to a sensible
value

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 <[email protected]>

Signed-off-by Felipe Balbi <[email protected]>

drivers/usb/gadget/composite.c +7 -2

index f6a7583ab6d1..0426d3c1fff9 100644
@@ -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

index 3d0d5d94a62f..0f01c04d7cbd 100644
@@ -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);