[alsa-devel] [PATCH v4 6/6] ASoC: hdmi-codec: add IEC control.

[Arnaud Pouliquen]

Create 'IEC958 Playback Default' controls to support IEC61937 formats.
the use of the alsa control is optional, using 'iec_ctl' flag.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen at st.com>
---
 include/sound/hdmi-codec.h    |  1 +
 sound/soc/codecs/hdmi-codec.c | 54 ++++++++++++++++++++++++++++++++-----------
 2 files changed, 41 insertions(+), 14 deletions(-)

diff --git a/include/sound/hdmi-codec.h b/include/sound/hdmi-codec.h
index fc3a481..4366d9f 100644
--- a/include/sound/hdmi-codec.h
+++ b/include/sound/hdmi-codec.h
@@ -92,6 +92,7 @@ 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 bc47b9a..6d156ea 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[] = {
@@ -122,26 +123,29 @@ 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;
+	mutex_unlock(&hcp->current_stream_lock);
+
+	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;
+		}
 	}
 
 	ret = hdmi_codec_new_stream(substream, dai);
@@ -248,6 +252,27 @@ static int hdmi_codec_digital_mute(struct snd_soc_dai *dai, int mute)
 	return 0;
 }
 
+static int hdmi_codec_dai_probe(struct snd_soc_dai *dai)
+{
+	struct hdmi_codec_priv *hcp = snd_soc_dai_get_drvdata(dai);
+	struct snd_pcm_iec958_params *iec958_params;
+	const struct snd_kcontrol_new *ctrl;
+
+	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->mutex = &hcp->current_stream_lock;
+
+	ctrl = snd_pcm_iec958_ctl_new(SNDRV_PCM_STREAM_PLAYBACK);
+	return snd_soc_add_dai_pcm_controls(dai, ctrl, 1, iec958_params);
+}
+
 static const struct snd_soc_dai_ops hdmi_dai_ops = {
 	.startup	= hdmi_codec_startup,
 	.shutdown	= hdmi_codec_shutdown,
@@ -293,6 +318,7 @@ static struct snd_soc_dai_driver hdmi_i2s_dai = {
 		.sig_bits = 24,
 	},
 	.ops = &hdmi_dai_ops,
+	.probe = hdmi_codec_dai_probe,
 };
 
 static const struct snd_soc_dai_driver hdmi_spdif_dai = {
-- 
1.9.1