From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Subject: Re: [PATCH v2 10/10] ALSA: hda: replace .wallclock by
 .get_time_info
Date: Sat, 20 Dec 2014 11:50:45 -0600
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>> +               audio_tstamp_report->accuracy_m = 42; /* 24 MHz WallClock
> == 42ns resolution */
>> +               audio_tstamp_report->accuracy_e = 0;
>> +
>
> Do you mean wall clock run at 48000 * 500 Hz ? 42.666ns

HDAudio wall clock (and bit clock) runs at 24MHz. So yes that's 48000 * 500.

> Those aureal sound cards also can provide time stamp using VORTEX_SMP_TIME
> mmio register which tick at 48000 * 256 Hz ?

then it should be fairly easy to implement the same feature...