diff options
Diffstat (limited to 'drivers/media/usb/uvc/uvc_video.c')
| -rw-r--r-- | drivers/media/usb/uvc/uvc_video.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c index b2e70fcf4eb4..d6ca383f643e 100644 --- a/drivers/media/usb/uvc/uvc_video.c +++ b/drivers/media/usb/uvc/uvc_video.c @@ -558,6 +558,17 @@ uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf, stream->clock.last_sof = dev_sof; host_sof = usb_get_current_frame_number(stream->dev->udev); + + /* + * On some devices, like the Logitech C922, the device SOF does not run + * at a stable rate of 1kHz. For those devices use the host SOF instead. + * In the tests performed so far, this improves the timestamp precision. + * This is probably explained by a small packet handling jitter from the + * host, but the exact reason hasn't been fully determined. + */ + if (stream->dev->quirks & UVC_QUIRK_INVALID_DEVICE_SOF) + dev_sof = host_sof; + time = uvc_video_get_time(); /* |