2017-03-02 08:45:19

by Roger Quadros

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

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: <[email protected]> # v4.9+
Signed-off-by: Roger Quadros <[email protected]>
---
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;
}

--
2.7.4

2017-03-02 10:49:25

by Laurent Pinchart

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

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: <[email protected]> # v4.9+
> Signed-off-by: Roger Quadros <[email protected]>

Acked-by: Laurent Pinchart <[email protected]>

> ---
> 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