[media] uvcvideo: Set alternate setting 0 on resume if the bus has been reset
authorMing Lei <tom.leiming@gmail.com>
Sat, 16 Jul 2011 03:51:00 +0000 (00:51 -0300)
committerMauro Carvalho Chehab <mchehab@redhat.com>
Thu, 22 Sep 2011 01:17:14 +0000 (22:17 -0300)
If the bus has been reset on resume, set the alternate setting to 0.
This should be the default value, but some devices crash or otherwise
misbehave if they don't receive a SET_INTERFACE request before any other
video control request.

Microdia's 0c45:6437 camera has been found to require this change or it
will stop sending video data after resume.

uvc_video.c]

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
drivers/media/video/uvc/uvc_driver.c
drivers/media/video/uvc/uvc_video.c
drivers/media/video/uvc/uvcvideo.h

index d29f9c2..e4100b1 100644 (file)
@@ -1961,7 +1961,7 @@ static int __uvc_resume(struct usb_interface *intf, int reset)
 
        list_for_each_entry(stream, &dev->streams, list) {
                if (stream->intf == intf)
-                       return uvc_video_resume(stream);
+                       return uvc_video_resume(stream, reset);
        }
 
        uvc_trace(UVC_TRACE_SUSPEND, "Resume: video streaming USB interface "
index 8244167..ffd1158 100644 (file)
@@ -1104,10 +1104,18 @@ int uvc_video_suspend(struct uvc_streaming *stream)
  * buffers, making sure userspace applications are notified of the problem
  * instead of waiting forever.
  */
-int uvc_video_resume(struct uvc_streaming *stream)
+int uvc_video_resume(struct uvc_streaming *stream, int reset)
 {
        int ret;
 
+       /* If the bus has been reset on resume, set the alternate setting to 0.
+        * This should be the default value, but some devices crash or otherwise
+        * misbehave if they don't receive a SET_INTERFACE request before any
+        * other video control request.
+        */
+       if (reset)
+               usb_set_interface(stream->dev->udev, stream->intfnum, 0);
+
        stream->frozen = 0;
 
        ret = uvc_commit_video(stream, &stream->ctrl);
index df32a43..cbdd49b 100644 (file)
@@ -638,7 +638,7 @@ extern void uvc_mc_cleanup_entity(struct uvc_entity *entity);
 /* Video */
 extern int uvc_video_init(struct uvc_streaming *stream);
 extern int uvc_video_suspend(struct uvc_streaming *stream);
-extern int uvc_video_resume(struct uvc_streaming *stream);
+extern int uvc_video_resume(struct uvc_streaming *stream, int reset);
 extern int uvc_video_enable(struct uvc_streaming *stream, int enable);
 extern int uvc_probe_video(struct uvc_streaming *stream,
                struct uvc_streaming_control *probe);