Commit 78daea29 authored by Dylan Reid's avatar Dylan Reid Committed by Takashi Iwai

ALSA: hda - Apply codec delay to wallclock.

For playback add the codec-side delay to the timestamp, for capture
subtract it.  This brings the timestamps in line with the time that
was recently added to the delay reporting.
Signed-off-by: default avatarDylan Reid <>
Signed-off-by: default avatarTakashi Iwai <>
parent 42397004
......@@ -1889,6 +1889,23 @@ static void azx_timecounter_init(struct snd_pcm_substream *substream,
tc->cycle_last = last;
static u64 azx_subtract_codec_delay(struct snd_pcm_substream *substream,
u64 nsec)
struct azx_pcm *apcm = snd_pcm_substream_chip(substream);
struct hda_pcm_stream *hinfo = apcm->hinfo[substream->stream];
u64 codec_frames, codec_nsecs;
if (!hinfo->ops.get_delay)
return nsec;
codec_frames = hinfo->ops.get_delay(hinfo, apcm->codec, substream);
codec_nsecs = div_u64(codec_frames * 1000000000LL,
return (nsec > codec_nsecs) ? nsec - codec_nsecs : 0;
static int azx_get_wallclock_tstamp(struct snd_pcm_substream *substream,
struct timespec *ts)
......@@ -1897,6 +1914,7 @@ static int azx_get_wallclock_tstamp(struct snd_pcm_substream *substream,
nsec = timecounter_read(&azx_dev->azx_tc);
nsec = div_u64(nsec, 3); /* can be optimized */
nsec = azx_subtract_codec_delay(substream, nsec);
*ts = ns_to_timespec(nsec);
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