Re: [PATCH 1/2] usb: gadget: f_uvc: Fix SuperSpeed companion descriptor's wBytesPerInterval

[Roger Quadros <rogerq@ti.com>]

Felipe,

On 08/03/17 16:05, Roger Quadros wrote:
> The streaming_maxburst module parameter is 0 offset (0..15)
> so we must add 1 while using it for wBytesPerInterval
> calculation for the SuperSpeed companion descriptor.
> 
> Without this host uvcvideo driver will always see the wrong
> wBytesPerInterval for SuperSpeed uvc gadget and may not find
> a suitable video interface endpoint.
> e.g. for streaming_maxburst = 0 case it will always
> fail as wBytePerInterval was evaluating to 0.
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Roger Quadros <rogerq@ti.com>

Please pick this one for v4.11-rc with Laurent's Reviewed-by. Thanks.

> ---
>  drivers/usb/gadget/function/f_uvc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
> index 29b41b5..c7689d0 100644
> --- a/drivers/usb/gadget/function/f_uvc.c
> +++ b/drivers/usb/gadget/function/f_uvc.c
> @@ -625,7 +625,7 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
>  	uvc_ss_streaming_comp.bMaxBurst = opts->streaming_maxburst;
>  	uvc_ss_streaming_comp.wBytesPerInterval =
>  		cpu_to_le16(max_packet_size * max_packet_mult *
> -			    opts->streaming_maxburst);
> +			    (opts->streaming_maxburst + 1));
>  
>  	/* Allocate endpoints. */
>  	ep = usb_ep_autoconfig(cdev->gadget, &uvc_control_ep);
> 

-- 
cheers,
-roger