From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jaroslav Kysela <perex@perex.cz>
Subject: Re: AES/SPDIF channel status bits in ALSA
Date: Thu, 08 Jan 2015 14:27:10 +0100
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Cc: Petr Kulhavy <petr@barix.com>
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Dne 8.1.2015 v 14:14 Petr Kulhavy napsal(a):
> Hi,
> 
> is there a way to get the channel status bits information from an AES or 
> SPDIF input interface through ALSA and read it in userspace?
> I'm trying to solve some issues with the channel status bits sent from a 
> custom hardware and finding a way to analyse the channel status info.

Look for the IEC958 controls (amixer -c <cardnumber> contents), but most
hardware / drivers do not pass this information.

Some hardware is also able to receive the whole spdif frames - look for
drivers with SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_* types (like cmipci).

				Jaroslav

-- 
Jaroslav Kysela <perex@perex.cz>
Linux Kernel Sound Maintainer
ALSA Project; Red Hat, Inc.