This is a note to let you know that I've just added the patch titled usb: gadget: composite: always set ep->mult to a sensible value to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: usb-gadget-composite-always-set-ep-mult-to-a-sensible-value.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From eaa496ffaaf19591fe471a36cef366146eeb9153 Mon Sep 17 00:00:00 2001 From: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> Date: Wed, 28 Sep 2016 12:33:31 +0300 Subject: usb: gadget: composite: always set ep->mult to a sensible value From: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> commit eaa496ffaaf19591fe471a36cef366146eeb9153 upstream. 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@xxxxxxxxxxxxxxx> Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/gadget/composite.c | 9 +++++++-- drivers/usb/gadget/function/uvc_video.c | 2 +- 2 files changed, 8 insertions(+), 3 deletions(-) --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -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(_ep->desc) & 0x7ff; + 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; --- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -243,7 +243,7 @@ uvc_video_alloc_requests(struct uvc_vide 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); Patches currently in stable-queue which might be from felipe.balbi@xxxxxxxxxxxxxxx are queue-4.9/usb-gadget-composite-always-set-ep-mult-to-a-sensible-value.patch queue-4.9/usb-gadget-f_uac2-fix-error-handling-at-afunc_bind.patch queue-4.9/usb-dwc3-gadget-set-pcm1-field-of-isochronous-first-trbs.patch queue-4.9/usb-gadget-composite-correctly-initialize-ep-maxpacket.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html