Re: [PATCH 3/7] usb: gadget: uvc: test if ep->desc is valid on ep_queue

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Michael,

Thank you for the patch.

On Thu, Sep 30, 2021 at 12:27:13PM +0200, Michael Grzeschik wrote:
> The reason that the ep_queue has failed could be an disabled endpoint.

s/an/a/

> In that case it is not guaranteed that the ep->desc is still valid.
> This patch adds an check for NULL.

s/an/a/

> Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
> ---
>  drivers/usb/gadget/function/uvc_video.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c
> index da93b46df464d..cdfd3726a86ae 100644
> --- a/drivers/usb/gadget/function/uvc_video.c
> +++ b/drivers/usb/gadget/function/uvc_video.c
> @@ -199,9 +199,11 @@ static int uvcg_video_ep_queue(struct uvc_video *video, struct usb_request *req)
>  		uvcg_err(&video->uvc->func, "Failed to queue request (%d).\n",
>  			 ret);
>  
> -		/* Isochronous endpoints can't be halted. */
> -		if (usb_endpoint_xfer_bulk(video->ep->desc))
> -			usb_ep_set_halt(video->ep);

I'd add a comment here:

		/* If the endpoint is disabled the descriptor may be NULL. */

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> +		if (video->ep->desc) {
> +			/* Isochronous endpoints can't be halted. */
> +			if (usb_endpoint_xfer_bulk(video->ep->desc))
> +				usb_ep_set_halt(video->ep);
> +		}
>  	}
>  
>  	return ret;

-- 
Regards,

Laurent Pinchart