Re: [PATCH] media: uvcvideo: Shorten the transfer size non compliance message

Laurent Pinchart
2025-09-08T08:37:19Z

On Thu, Sep 04, 2025 at 08:14:29AM +0200, Michal Pecio wrote:
> This message is much longer than others and doesn't fit even in a 160
> column window when printed, despite providing little real information.
>
> Also replace 'transmission' with 'transfer' because that's the actual
> name and 'max packet' with 'limit' because it isn't same thing with
> isochronus endpoints. Remove cryptic abbreviations like 'ep'.
>
> Signed-off-by: Michal Pecio <michal.pecio@gmail.com>
> ---
>
> By the way, this hack doesn't help much in the opposite case:
> dwMaxPayloadTransferSize is right, but EP descriptors are a mess.

Have you encountered such devices ?

> But no harm in trying, I guess.
> I can live with it either way.
>
> drivers/media/usb/uvc/uvc_video.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
> index 82d9d8ae059d..baf4ace41dbe 100644
> --- a/drivers/media/usb/uvc/uvc_video.c
> +++ b/drivers/media/usb/uvc/uvc_video.c
> @@ -266,7 +266,7 @@ static void uvc_fixup_video_ctrl(struct uvc_streaming *stream,
> if (stream->intf->num_altsetting > 1 &&
> ctrl->dwMaxPayloadTransferSize > stream->maxpsize) {
> dev_warn_ratelimited(&stream->intf->dev,
> - "UVC non compliance: the max payload transmission size (%u) exceeds the size of the ep max packet (%u). Using the max size.\n",
> + "UVC non compliance: Reducing max payload transfer size (%u) to fit endpoint limit (%u).\n",
> ctrl->dwMaxPayloadTransferSize,
> stream->maxpsize);
> ctrl->dwMaxPayloadTransferSize = stream->maxpsize;

--
Regards,

Laurent Pinchart