diff options
| -rw-r--r-- | drivers/media/usb/uvc/uvc_video.c | 83 |
1 files changed, 36 insertions, 47 deletions
diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c index af25b9f1b53f..5df8f61d39cd 100644 --- a/drivers/media/usb/uvc/uvc_video.c +++ b/drivers/media/usb/uvc/uvc_video.c @@ -466,19 +466,28 @@ static inline ktime_t uvc_video_get_time(void) return ktime_get_real(); } +static void uvc_video_clock_add_sample(struct uvc_clock *clock, + const struct uvc_clock_sample *sample) +{ + unsigned long flags; + + spin_lock_irqsave(&clock->lock, flags); + + clock->samples[clock->head] = *sample; + clock->head = (clock->head + 1) % clock->size; + clock->count = min(clock->count + 1, clock->size); + + spin_unlock_irqrestore(&clock->lock, flags); +} + static void uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf, const u8 *data, int len) { - struct uvc_clock_sample *sample; + struct uvc_clock_sample sample; unsigned int header_size; bool has_pts = false; bool has_scr = false; - unsigned long flags; - ktime_t time; - u16 host_sof; - u16 dev_sof; - u32 dev_stc; switch (data[1] & (UVC_STREAM_PTS | UVC_STREAM_SCR)) { case UVC_STREAM_PTS | UVC_STREAM_SCR: @@ -523,11 +532,11 @@ uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf, * all the data packets of the same frame contains the same SOF. In that * case only the first one will match the host_sof. */ - dev_sof = get_unaligned_le16(&data[header_size - 2]); - if (dev_sof == stream->clock.last_sof) + sample.dev_sof = get_unaligned_le16(&data[header_size - 2]); + if (sample.dev_sof == stream->clock.last_sof) return; - dev_stc = get_unaligned_le32(&data[header_size - 6]); + sample.dev_stc = get_unaligned_le32(&data[header_size - 6]); /* * STC (Source Time Clock) is the clock used by the camera. The UVC 1.5 @@ -552,12 +561,10 @@ uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf, * suffer from this condition. */ if (buf && buf->bytesused == 0 && len == header_size && - dev_stc == 0 && dev_sof == 0) + sample.dev_stc == 0 && sample.dev_sof == 0) return; - stream->clock.last_sof = dev_sof; - - host_sof = usb_get_current_frame_number(stream->dev->udev); + sample.host_sof = usb_get_current_frame_number(stream->dev->udev); /* * On some devices, like the Logitech C922, the device SOF does not run @@ -567,9 +574,9 @@ uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf, * host, but the exact reason hasn't been fully determined. */ if (stream->dev->quirks & UVC_QUIRK_INVALID_DEVICE_SOF) - dev_sof = host_sof; + sample.dev_sof = sample.host_sof; - time = uvc_video_get_time(); + sample.host_time = uvc_video_get_time(); /* * The UVC specification allows device implementations that can't obtain @@ -592,46 +599,28 @@ uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf, * the 8 LSBs of the delta are kept. */ if (stream->clock.sof_offset == (u16)-1) { - u16 delta_sof = (host_sof - dev_sof) & 255; + u16 delta_sof = (sample.host_sof - sample.dev_sof) & 255; if (delta_sof >= 10) stream->clock.sof_offset = delta_sof; else stream->clock.sof_offset = 0; } - dev_sof = (dev_sof + stream->clock.sof_offset) & 2047; - - spin_lock_irqsave(&stream->clock.lock, flags); - - sample = &stream->clock.samples[stream->clock.head]; - sample->dev_stc = dev_stc; - sample->dev_sof = dev_sof; - sample->host_sof = host_sof; - sample->host_time = time; - - /* Update the sliding window head and count. */ - stream->clock.head = (stream->clock.head + 1) % stream->clock.size; - - if (stream->clock.count < stream->clock.size) - stream->clock.count++; - - spin_unlock_irqrestore(&stream->clock.lock, flags); + sample.dev_sof = (sample.dev_sof + stream->clock.sof_offset) & 2047; + uvc_video_clock_add_sample(&stream->clock, &sample); + stream->clock.last_sof = sample.dev_sof; } -static void uvc_video_clock_reset(struct uvc_streaming *stream) +static void uvc_video_clock_reset(struct uvc_clock *clock) { - struct uvc_clock *clock = &stream->clock; - clock->head = 0; clock->count = 0; clock->last_sof = -1; clock->sof_offset = -1; } -static int uvc_video_clock_init(struct uvc_streaming *stream) +static int uvc_video_clock_init(struct uvc_clock *clock) { - struct uvc_clock *clock = &stream->clock; - spin_lock_init(&clock->lock); clock->size = 32; @@ -640,15 +629,15 @@ static int uvc_video_clock_init(struct uvc_streaming *stream) if (clock->samples == NULL) return -ENOMEM; - uvc_video_clock_reset(stream); + uvc_video_clock_reset(clock); return 0; } -static void uvc_video_clock_cleanup(struct uvc_streaming *stream) +static void uvc_video_clock_cleanup(struct uvc_clock *clock) { - kfree(stream->clock.samples); - stream->clock.samples = NULL; + kfree(clock->samples); + clock->samples = NULL; } /* @@ -2123,7 +2112,7 @@ int uvc_video_resume(struct uvc_streaming *stream, int reset) stream->frozen = 0; - uvc_video_clock_reset(stream); + uvc_video_clock_reset(&stream->clock); if (!uvc_queue_streaming(&stream->queue)) return 0; @@ -2272,7 +2261,7 @@ int uvc_video_start_streaming(struct uvc_streaming *stream) { int ret; - ret = uvc_video_clock_init(stream); + ret = uvc_video_clock_init(&stream->clock); if (ret < 0) return ret; @@ -2290,7 +2279,7 @@ int uvc_video_start_streaming(struct uvc_streaming *stream) error_video: usb_set_interface(stream->dev->udev, stream->intfnum, 0); error_commit: - uvc_video_clock_cleanup(stream); + uvc_video_clock_cleanup(&stream->clock); return ret; } @@ -2318,5 +2307,5 @@ void uvc_video_stop_streaming(struct uvc_streaming *stream) usb_clear_halt(stream->dev->udev, pipe); } - uvc_video_clock_cleanup(stream); + uvc_video_clock_cleanup(&stream->clock); } |