Hi Ricardo, Thank you for your patch. On 8-Oct-24 5:00 PM, Ricardo Ribalda wrote: > If we fail to query the ctrl error code there is no information on dmesg > or in uvc_dbg. This makes difficult to debug the issue. > > Print a proper error message when we cannot retrieve the error code from > the device. > > Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> > --- > drivers/media/usb/uvc/uvc_video.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c > index f125b3ba50f2..6efbfa609059 100644 > --- a/drivers/media/usb/uvc/uvc_video.c > +++ b/drivers/media/usb/uvc/uvc_video.c > @@ -111,8 +111,12 @@ int uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit, > error = *(u8 *)data; > *(u8 *)data = tmp; > > - if (ret != 1) > - return ret < 0 ? ret : -EPIPE; > + if (ret != 1) { > + dev_err(&dev->udev->dev, > + "Failed to query (%s) UVC error code control %u on unit %u: %d (exp. 1).\n", > + uvc_query_name(query), cs, unit, ret); > + return ret ? ret : -EPIPE; Adding error logging is always good, but again please drop the change to the return condition and stick with the: return ret < 0 ? ret : -EPIPE; pattern used everywhere. Also in this case the return condition change really should have been in a separate patch since unlike before the success condition did not change, so it really is unrelated to adding the error logging. Regards, Hans