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ALSA: hda: read trigger_timestamp immediately after starting DMA 

Make sure wallclock counter and trigger timestamp are read very
close to each other for better alignment.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Pierre-Louis Bossart 2015-02-06 15:55:52 -06:00 committed by Takashi Iwai
parent 2b79d7a6bf
commit ed610af86a
1 changed files with 3 additions and 0 deletions
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3
sound/pci/hda/hda_controller.c
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@ -657,6 +657,9 @@ static int azx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
azx_writel(chip, SSYNC, azx_readl(chip, SSYNC) & ~sbits);
if (start) {
azx_timecounter_init(substream, 0, 0);
snd_pcm_gettime(substream->runtime, &substream->runtime->trigger_tstamp);
substream->runtime->trigger_tstamp_latched = true;
if (nsync > 1) {
cycle_t cycle_last;