Re: [PATCH] Revert "usb: gadget: uvc: Add missing call for additional setup data"

From: Laurent Pinchart
Date: Thu Mar 02 2017 - 05:49:28 EST


Hi Roger,

Thank you for the patch.

On Thursday 02 Mar 2017 10:44:58 Roger Quadros wrote:
> This reverts commit 4fbac5206afd01b717d4bdc58793d471f3391b4b.
>
> This commit breaks g_webcam when used with uvc-gadget [1].
>
> The user space application (e.g. uvc-gadget) is responsible for
> sending response to UVC class specific requests on control endpoint
> in uvc_send_response() in uvc_v4l2.c.
>
> The bad commit was causing a duplicate response to be sent with
> incorrect response data thus causing UVC probe to fail at the host
> and broken control transfer endpoint at the gadget.
>
> [1] - git://git.ideasonboard.org/uvc-gadget.git
>
> Cc: <stable@xxxxxxxxxxxxxxx> # v4.9+
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>

Acked-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

> ---
> drivers/usb/gadget/function/f_uvc.c | 7 -------
> 1 file changed, 7 deletions(-)
>
> diff --git a/drivers/usb/gadget/function/f_uvc.c
> b/drivers/usb/gadget/function/f_uvc.c index 27ed51b..29b41b5 100644
> --- a/drivers/usb/gadget/function/f_uvc.c
> +++ b/drivers/usb/gadget/function/f_uvc.c
> @@ -258,13 +258,6 @@ uvc_function_setup(struct usb_function *f, const struct
> usb_ctrlrequest *ctrl) memcpy(&uvc_event->req, ctrl,
> sizeof(uvc_event->req));
> v4l2_event_queue(&uvc->vdev, &v4l2_event);
>
> - /* Pass additional setup data to userspace */
> - if (uvc->event_setup_out && uvc->event_length) {
> - uvc->control_req->length = uvc->event_length;
> - return usb_ep_queue(uvc->func.config->cdev->gadget->ep0,
> - uvc->control_req, GFP_ATOMIC);
> - }
> -
> return 0;
> }

--
Regards,

Laurent Pinchart