[alsa-devel] [RFC v2 5/6] ASoc: hdmi-codec: add IEC control.

[Arnaud Pouliquen]

On 02/06/2016 08:29 PM, Jyri Sarha wrote:
> On 01/22/16 19:48, Arnaud Pouliquen wrote:
>> Create 'IEC958 Playback Default' controls to support IEC61937 formats.
>> the use of the alsa control is optional, using 'iec_ctl' flag.
>>
> 
> I applied the patches "ALSA: pcm: add IEC958 channel status control 
> helper", "ASoC: core: add code to complete dai init after pcm creation", 
> and "ASoc: hdmi-codec: add IEC control" to my BBB HDMI audio branch. I 
> needed to do some trivial conflict solving, but after that everything 
> compiled fine. However, when I tried to read the iec mixer with:
> 
> # amixer -c0 cget name='IEC958 Playback Default',device=0
> amixer: Cannot find the given element from control hw:0
> 
> The same command worked just fine on my intel based laptop:
> # amixer -c0 cget iface=MIXER,name='IEC958 Playback Default',device=0
> numid=31,iface=MIXER,name='IEC958 Playback Default'
>    ; type=IEC958,access=rw------,values=1
>    : values=[AES0=0x04 AES1=0x00 AES2=0x00 AES3=0x00]
Do you enable "iec_ctl" field in hdmi_codec_pdata structure?
i add this field because control can be declared and used by CPU DAI or
codec, depending on hardware.

> 
> How did you test the mixer yourself?
To test on my platform i hacked my code because control is handled by
CPU_DAI...
But just by disabling control creation in CPU DAI for HDMI and set
"iec_ctl" filed to 1, i can see and use the control.

**** List of PLAYBACK Hardware Devices ****
card 0: Default [sti audio card], device 0: Uni Player #0
(HDMI)-i2s-hifi i2s-hifi-0 []
card 0: Default [sti audio card], device 1: Uni Player #1
(DAC)-sas-dai-dac sas-dai-dac-1 []
card 0: Default [sti audio card], device 2: Uni Player #1
(PIO)-sas-dai-spdif-out sas-dai-spdif-out-2 []

# amixer -c0 controls | grep IEC958
numid=5,iface=PCM,name='IEC958 Playback Default'
numid=3,iface=PCM,name='IEC958 Playback Default',device=3


BR,
Arnaud
> 
> Best regards,
> Jyri
> 
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen at st.com>
>> ---
>>   include/sound/hdmi-codec.h    |  1 +
>>   sound/soc/codecs/hdmi-codec.c | 59 +++++++++++++++++++++++++++++++++----------
>>   2 files changed, 46 insertions(+), 14 deletions(-)
>>
>> diff --git a/include/sound/hdmi-codec.h b/include/sound/hdmi-codec.h
>> index ed780b2..58e8eae 100644
>> --- a/include/sound/hdmi-codec.h
>> +++ b/include/sound/hdmi-codec.h
>> @@ -96,6 +96,7 @@ struct hdmi_codec_pdata {
>>   	const struct hdmi_codec_ops *ops;
>>   	uint i2s:1;
>>   	uint spdif:1;
>> +	uint iec_ctl:1;
>>   	int max_i2s_channels;
>>   };
>>
>> diff --git a/sound/soc/codecs/hdmi-codec.c b/sound/soc/codecs/hdmi-codec.c
>> index 94349b3..1b6cb5a 100644
>> --- a/sound/soc/codecs/hdmi-codec.c
>> +++ b/sound/soc/codecs/hdmi-codec.c
>> @@ -32,6 +32,7 @@ struct hdmi_codec_priv {
>>   	struct snd_pcm_substream *current_stream;
>>   	struct snd_pcm_hw_constraint_list ratec;
>>   	uint8_t eld[MAX_ELD_BYTES];
>> +	struct snd_aes_iec958 iec;
>>   };
>>
>>   static const struct snd_soc_dapm_widget hdmi_widgets[] = {
>> @@ -140,27 +141,30 @@ static int hdmi_codec_hw_params(struct snd_pcm_substream *substream,
>>   				struct snd_soc_dai *dai)
>>   {
>>   	struct hdmi_codec_priv *hcp = snd_soc_dai_get_drvdata(dai);
>> -	struct hdmi_codec_params hp = {
>> -		.iec = {
>> -			.status = { 0 },
>> -			.subcode = { 0 },
>> -			.pad = 0,
>> -			.dig_subframe = { 0 },
>> -		}
>> -	};
>> +	struct hdmi_codec_params hp;
>>   	int ret;
>>
>>   	dev_dbg(dai->dev, "%s() width %d rate %d channels %d\n", __func__,
>>   		params_width(params), params_rate(params),
>>   		params_channels(params));
>>
>> -	ret = snd_pcm_create_iec958_consumer_hw_params(params, hp.iec.status,
>> -						       sizeof(hp.iec.status));
>> -	if (ret < 0) {
>> -		dev_err(dai->dev, "Creating IEC958 channel status failed %d\n",
>> -			ret);
>> -		return ret;
>> +	mutex_lock(&hcp->current_stream_lock);
>> +	hp.iec = hcp->iec;
>> +
>> +	if (!hcp->hcd.iec_ctl) {
>> +		/*
>> +		* only PCM format supported
>> +		*channel status set according to runtime parameters
>> +		*/
>> +		ret = snd_pcm_create_iec958_consumer_hw_params(params,
>> +					hp.iec.status, sizeof(hp.iec.status));
>> +		if (ret < 0) {
>> +			dev_err(dai->dev, "Creating IEC958 status failed %d\n",
>> +				ret);
>> +			return ret;
>> +		}
>>   	}
>> +	mutex_unlock(&hcp->current_stream_lock);
>>
>>   	ret = hdmi_codec_new_stream(substream, dai);
>>   	if (ret)
>> @@ -266,12 +270,37 @@ static int hdmi_codec_digital_mute(struct snd_soc_dai *dai, int mute)
>>   	return 0;
>>   }
>>
>> +static int hdmi_codec_pcm_new(struct snd_soc_pcm_runtime *rtd,
>> +			      struct snd_soc_dai *dai)
>> +{
>> +	struct hdmi_codec_priv *hcp = snd_soc_dai_get_drvdata(dai);
>> +	struct snd_pcm_iec958_params *iec958_params;
>> +
>> +	dev_dbg(dai->dev, "%s()\n", __func__);
>> +
>> +	if (!hcp->hcd.iec_ctl)
>> +		return 0;
>> +
>> +	iec958_params = devm_kzalloc(dai->dev, sizeof(*iec958_params),
>> +				     GFP_KERNEL);
>> +	if (!iec958_params)
>> +		return -ENOMEM;
>> +
>> +	iec958_params->iec = &hcp->iec;
>> +	iec958_params->pdata = hcp;
>> +	iec958_params->mutex = &hcp->current_stream_lock;
>> +
>> +	return snd_pcm_create_iec958_ctl(rtd->pcm, iec958_params,
>> +					 SNDRV_PCM_STREAM_PLAYBACK);
>> +}
>> +
>>   static const struct snd_soc_dai_ops hdmi_dai_ops = {
>>   	.startup        = hdmi_codec_startup,
>>   	.shutdown       = hdmi_codec_shutdown,
>>   	.hw_params      = hdmi_codec_hw_params,
>>   	.set_fmt        = hdmi_codec_set_fmt,
>>   	.digital_mute   = hdmi_codec_digital_mute,
>> +	.pcm_new        = hdmi_codec_pcm_new,
>>   };
>>
>>
>> @@ -352,6 +381,8 @@ static int hdmi_codec_probe(struct platform_device *pdev)
>>   	if (!hcp)
>>   		return -ENOMEM;
>>
>> +	memset(&hcp->iec, 0, sizeof(hcp->iec));
>> +
>>   	hcp->hcd = *hcd;
>>   	mutex_init(&hcp->current_stream_lock);
>>
>>
>