When USB requests for video data fail to be submitted, the driver signals a problem to the host by halting the video streaming endpoint. This is only valid in bulk mode, as isochronous transfers have no handshake phase and can't thus report a stall. The usb_ep_set_halt() call returns an error when using isochronous endpoints, which we happily ignore, but some UDCs complain in the kernel log. Fix this by only trying to halt the endpoint in bulk mode. Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> --- drivers/usb/gadget/function/uvc_video.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c index a95c8e2364ed..2c9821ec836e 100644 --- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -132,7 +132,9 @@ static int uvcg_video_ep_queue(struct uvc_video *video, struct usb_request *req) ret = usb_ep_queue(video->ep, req, GFP_ATOMIC); if (ret < 0) { printk(KERN_INFO "Failed to queue request (%d).\n", ret); - usb_ep_set_halt(video->ep); + /* 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