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>

diff --git a/sound/pci/hda/hda_controller.c b/sound/pci/hda/hda_controller.c
index 27dcb14..dfcb5e9 100644 (file)
--- a/sound/pci/hda/hda_controller.c
+++ b/sound/pci/hda/hda_controller.c
@@ -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;