[alsa-devel] [PATCH] ALSA: hda - Fix the workaround for conflicting IEC958 controls

[Anssi Hannula]

10.02.2013 12:38, Takashi Iwai kirjoitti:
> At Sat,  9 Feb 2013 00:44:39 +0200,
> Anssi Hannula wrote:
>>
>> Commit dcda5806165c155d90b9aa466a1602cf4726012b ("ALSA: hda - Add
>> workaround for conflicting IEC958 controls") added a workaround for
>> cards that have both an S/PDIF and an HDMI device, so that S/PDIF IEC958
>> controls will be moved to device=1 on such cards.
>>
>> However, the workaround did not take it into account that the S/PDIF and
>> HDMI devices may be on different codecs of the same card. Currently this
>> is always the case, and the workaround therefore fails to work.
>>
>> Fix the workaround to handle card-wide IEC958 conflicts.
>>
>> Reported-by: Stephan Raue <stephan at openelec.tv>
>> Signed-off-by: Anssi Hannula <anssi.hannula at iki.fi>
>> ---
>>
>> Unfortunately this seems to cause a nasty issue with alsa-lib 1.0.26:
>> $ amixer scontrols -c 0
>> ALSA lib simple_none.c:1551:(simple_add1) helem (MIXER,'IEC958 Playback Switch',0,1,0) appears twice or more
>> amixer: Mixer hw:0 load error: Invalid argument
>>
>> The non-simple-mode "amixer controls -c 0" works fine, though.
>>
>> Not really sure what to do now then, do we revert the workaround
>> completely and devise a different workaround/fix for this, or do you
>> have some other good ideas?
> 
> If the element isn't really dup'ed, it must be a bug in alsa-lib mixer
> abstraction, so it should be fixed there.

This is because the simple mixer interface only identifies controls by
name+index:
http://www.alsa-project.org/alsa-doc/alsa-lib/group___simple_mixer.html

So controls that only differ by device (or subdevice?) are considered
duplicated. I did look at the code but saw no straight-forward way to
fix it, other than to introduce devices (and subdevices) to the simple
mixer API (which is used by outside applications).

Anyway, wouldn't breaking "old" alsa-lib make this way of fixing it a
no-go (the error is fatal and mixer creation fails completely)?

> Could you add alsa-info.sh output of this board (at best before and
> after your patch)?

Here's one after patch (can't get one before patch right now, but I
guess it isn't needed since the cause is very clear):
http://www.alsa-project.org/db/?f=bb3fc8680b372c0475719d42d7fc8b2bb7bfb4eb
(this one has alsa-lib hack applied which ignores the failure to add the
control so that the mixer error is non-fatal)

> 
> thanks,
> 
> Takashi
> 
> 
>>
>>
>>  sound/pci/hda/hda_codec.c |   27 +++++++++++++++------------
>>  sound/pci/hda/hda_codec.h |    4 +++-
>>  2 files changed, 18 insertions(+), 13 deletions(-)
>>
>> diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
>> index 822df97..fe5d6fc 100644
>> --- a/sound/pci/hda/hda_codec.c
>> +++ b/sound/pci/hda/hda_codec.c
>> @@ -3135,25 +3135,28 @@ int snd_hda_create_dig_out_ctls(struct hda_codec *codec,
>>  	int idx, dev = 0;
>>  	const int spdif_pcm_dev = 1;
>>  	struct hda_spdif_out *spdif;
>> +	struct hda_codec *c;
>>  
>> -	if (codec->primary_dig_out_type == HDA_PCM_TYPE_HDMI &&
>> +	if (codec->bus->primary_dig_out_type == HDA_PCM_TYPE_HDMI &&
>>  	    type == HDA_PCM_TYPE_SPDIF) {
>>  		dev = spdif_pcm_dev;
>> -	} else if (codec->primary_dig_out_type == HDA_PCM_TYPE_SPDIF &&
>> +	} else if (codec->bus->primary_dig_out_type == HDA_PCM_TYPE_SPDIF &&
>>  		   type == HDA_PCM_TYPE_HDMI) {
>> -		for (idx = 0; idx < codec->spdif_out.used; idx++) {
>> -			spdif = snd_array_elem(&codec->spdif_out, idx);
>> -			for (dig_mix = dig_mixes; dig_mix->name; dig_mix++) {
>> -				kctl = find_mixer_ctl(codec, dig_mix->name, 0, idx);
>> -				if (!kctl)
>> -					break;
>> -				kctl->id.device = spdif_pcm_dev;
>> +		list_for_each_entry(c, &codec->bus->codec_list, list) {
>> +			for (idx = 0; idx < c->spdif_out.used; idx++) {
>> +				spdif = snd_array_elem(&c->spdif_out, idx);
>> +				for (dig_mix = dig_mixes; dig_mix->name; dig_mix++) {
>> +					kctl = find_mixer_ctl(c, dig_mix->name, 0, idx);
>> +					if (!kctl)
>> +						break;
>> +					kctl->id.device = spdif_pcm_dev;
>> +				}
>>  			}
>>  		}
>> -		codec->primary_dig_out_type = HDA_PCM_TYPE_HDMI;
>> +		codec->bus->primary_dig_out_type = HDA_PCM_TYPE_HDMI;
>>  	}
>> -	if (!codec->primary_dig_out_type)
>> -		codec->primary_dig_out_type = type;
>> +	if (!codec->bus->primary_dig_out_type)
>> +		codec->bus->primary_dig_out_type = type;
>>  
>>  	idx = find_empty_mixer_ctl_idx(codec, "IEC958 Playback Switch", dev);
>>  	if (idx < 0) {
>> diff --git a/sound/pci/hda/hda_codec.h b/sound/pci/hda/hda_codec.h
>> index 8665540..ab807f7 100644
>> --- a/sound/pci/hda/hda_codec.h
>> +++ b/sound/pci/hda/hda_codec.h
>> @@ -671,6 +671,9 @@ struct hda_bus {
>>  	unsigned int response_reset:1;	/* controller was reset */
>>  	unsigned int in_reset:1;	/* during reset operation */
>>  	unsigned int power_keep_link_on:1; /* don't power off HDA link */
>> +
>> +	/* primary digital out PCM type */
>> +	int primary_dig_out_type;
>>  };
>>  
>>  /*
>> @@ -837,7 +840,6 @@ struct hda_codec {
>>  	struct mutex hash_mutex;
>>  	struct snd_array spdif_out;
>>  	unsigned int spdif_in_enable;	/* SPDIF input enable? */
>> -	int primary_dig_out_type;	/* primary digital out PCM type */
>>  	const hda_nid_t *slave_dig_outs; /* optional digital out slave widgets */
>>  	struct snd_array init_pins;	/* initial (BIOS) pin configurations */
>>  	struct snd_array driver_pins;	/* pin configs set by codec parser */
>> -- 
>> 1.7.10
>>
> 


-- 
Anssi Hannula