From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: [PATCH 2/2] ALSA: hda: support for wallclock
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Date: Sun, 30 Sep 2012 12:12:09 +0200
Message-ID: <50681AF9.8000004@ladisch.de>
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Pierre-Louis Bossart wrote:
> On 09/28/2012 04:33 AM, Clemens Ladisch wrote:
>> Pierre-Louis Bossart wrote:
>>> @@ -1712,6 +1777,7 @@ static struct snd_pcm_hardware azx_pcm_hw = {
>>>                    /* SNDRV_PCM_INFO_RESUME |*/
>>>                    SNDRV_PCM_INFO_PAUSE |
>>>                    SNDRV_PCM_INFO_SYNC_START |
>>> +                 SNDRV_PCM_INFO_HAS_WALL_CLOCK |
>>
>> ... but not if this device is connected to an S/PDIF input.
>
> Yeah, but I can't figure out what happens here. HDAudio is the clock
> master in all cases

Except for those cases described in section 5.4.3 of the HDA spec.

Finding out whether a device is connected to an S/PDIF input is not easy
and might change dynamically.

It might be easiest to omit HAS_WALL_CLOCK for inputs ...


Regards,
Clemens