ASoC: hdmi-codec: add channel mapping control

Add user interface to provide channel mapping.
In a first step this control is read only.

As TLV type, the control provides all configuration available for
HDMI sink(ELD), and provides current channel mapping selected by codec
based on ELD and number of channels specified by user on open.
When control is called before the number of the channel is specified
(i.e. hw_params is set), it returns all channels set to UNKNOWN.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/hdmi-codec.c

@@ -18,6 +18,7 @@
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/soc.h>
+#include <sound/tlv.h>
 #include <sound/pcm_drm_eld.h>
 #include <sound/hdmi-codec.h>
 #include <sound/pcm_iec958.h>
@@ -33,6 +34,258 @@ struct hdmi_device {
 LIST_HEAD(hdmi_device_list);
 
 #define DAI_NAME_SIZE 16
+
+#define HDMI_CODEC_CHMAP_IDX_UNKNOWN  -1
+
+struct hdmi_codec_channel_map_table {
+	unsigned char map;	/* ALSA API channel map position */
+	unsigned long spk_mask;		/* speaker position bit mask */
+};
+
+/*
+ * CEA speaker placement for HDMI 1.4:
+ *
+ *  FL  FLC   FC   FRC   FR   FRW
+ *
+ *                                  LFE
+ *
+ *  RL  RLC   RC   RRC   RR
+ *
+ *  Speaker placement has to be extended to support HDMI 2.0
+ */
+enum hdmi_codec_cea_spk_placement {
+	FL  = BIT(0),	/* Front Left           */
+	FC  = BIT(1),	/* Front Center         */
+	FR  = BIT(2),	/* Front Right          */
+	FLC = BIT(3),	/* Front Left Center    */
+	FRC = BIT(4),	/* Front Right Center   */
+	RL  = BIT(5),	/* Rear Left            */
+	RC  = BIT(6),	/* Rear Center          */
+	RR  = BIT(7),	/* Rear Right           */
+	RLC = BIT(8),	/* Rear Left Center     */
+	RRC = BIT(9),	/* Rear Right Center    */
+	LFE = BIT(10),	/* Low Frequency Effect */
+};
+
+/*
+ * cea Speaker allocation structure
+ */
+struct hdmi_codec_cea_spk_alloc {
+	const int ca_id;
+	unsigned int n_ch;
+	unsigned long mask;
+};
+
+/* Channel maps  stereo HDMI */
+const struct snd_pcm_chmap_elem hdmi_codec_stereo_chmaps[] = {
+	{ .channels = 2,
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
+	{ }
+};
+
+/* Channel maps for multi-channel playbacks, up to 8 n_ch */
+const struct snd_pcm_chmap_elem hdmi_codec_8ch_chmaps[] = {
+	{ .channels = 2, /* CA_ID 0x00 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR } },
+	{ .channels = 4, /* CA_ID 0x01 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_NA } },
+	{ .channels = 4, /* CA_ID 0x02 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FC } },
+	{ .channels = 4, /* CA_ID 0x03 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_FC } },
+	{ .channels = 6, /* CA_ID 0x04 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_RC, SNDRV_CHMAP_NA } },
+	{ .channels = 6, /* CA_ID 0x05 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_RC, SNDRV_CHMAP_NA } },
+	{ .channels = 6, /* CA_ID 0x06 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_RC, SNDRV_CHMAP_NA } },
+	{ .channels = 6, /* CA_ID 0x07 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_RC, SNDRV_CHMAP_NA } },
+	{ .channels = 6, /* CA_ID 0x08 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
+	{ .channels = 6, /* CA_ID 0x09 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
+	{ .channels = 6, /* CA_ID 0x0A */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
+	{ .channels = 6, /* CA_ID 0x0B */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR } },
+	{ .channels = 8, /* CA_ID 0x0C */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+		   SNDRV_CHMAP_RC, SNDRV_CHMAP_NA } },
+	{ .channels = 8, /* CA_ID 0x0D */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+		   SNDRV_CHMAP_RC, SNDRV_CHMAP_NA } },
+	{ .channels = 8, /* CA_ID 0x0E */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+		   SNDRV_CHMAP_RC, SNDRV_CHMAP_NA } },
+	{ .channels = 8, /* CA_ID 0x0F */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+		   SNDRV_CHMAP_RC, SNDRV_CHMAP_NA } },
+	{ .channels = 8, /* CA_ID 0x10 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+		   SNDRV_CHMAP_RLC, SNDRV_CHMAP_RRC } },
+	{ .channels = 8, /* CA_ID 0x11 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+		   SNDRV_CHMAP_RLC, SNDRV_CHMAP_RRC } },
+	{ .channels = 8, /* CA_ID 0x12 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+		   SNDRV_CHMAP_RLC, SNDRV_CHMAP_RRC } },
+	{ .channels = 8, /* CA_ID 0x13 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_RL, SNDRV_CHMAP_RR,
+		   SNDRV_CHMAP_RLC, SNDRV_CHMAP_RRC } },
+	{ .channels = 8, /* CA_ID 0x14 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x15 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x16 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x17 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x18 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x19 */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x1A */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x1B */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x1C */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x1D */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_NA, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x1E */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ .channels = 8, /* CA_ID 0x1F */
+	  .map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_FR, SNDRV_CHMAP_LFE,
+		   SNDRV_CHMAP_FC, SNDRV_CHMAP_NA, SNDRV_CHMAP_NA,
+		   SNDRV_CHMAP_FLC, SNDRV_CHMAP_FRC } },
+	{ }
+};
+
+/*
+ * hdmi_codec_channel_alloc: speaker configuration available for CEA
+ *
+ * This is an ordered list that must match with hdmi_codec_8ch_chmaps struct
+ * The preceding ones have better chances to be selected by
+ * hdmi_codec_get_ch_alloc_table_idx().
+ */
+static const struct hdmi_codec_cea_spk_alloc hdmi_codec_channel_alloc[] = {
+	{ .ca_id = 0x00, .n_ch = 2,
+	  .mask = FL | FR},
+	/* 2.1 */
+	{ .ca_id = 0x01, .n_ch = 4,
+	  .mask = FL | FR | LFE},
+	/* Dolby Surround */
+	{ .ca_id = 0x02, .n_ch = 4,
+	  .mask = FL | FR | FC },
+	/* surround51 */
+	{ .ca_id = 0x0b, .n_ch = 6,
+	  .mask = FL | FR | LFE | FC | RL | RR},
+	/* surround40 */
+	{ .ca_id = 0x08, .n_ch = 6,
+	  .mask = FL | FR | RL | RR },
+	/* surround41 */
+	{ .ca_id = 0x09, .n_ch = 6,
+	  .mask = FL | FR | LFE | RL | RR },
+	/* surround50 */
+	{ .ca_id = 0x0a, .n_ch = 6,
+	  .mask = FL | FR | FC | RL | RR },
+	/* 6.1 */
+	{ .ca_id = 0x0f, .n_ch = 8,
+	  .mask = FL | FR | LFE | FC | RL | RR | RC },
+	/* surround71 */
+	{ .ca_id = 0x13, .n_ch = 8,
+	  .mask = FL | FR | LFE | FC | RL | RR | RLC | RRC },
+	/* others */
+	{ .ca_id = 0x03, .n_ch = 8,
+	  .mask = FL | FR | LFE | FC },
+	{ .ca_id = 0x04, .n_ch = 8,
+	  .mask = FL | FR | RC},
+	{ .ca_id = 0x05, .n_ch = 8,
+	  .mask = FL | FR | LFE | RC },
+	{ .ca_id = 0x06, .n_ch = 8,
+	  .mask = FL | FR | FC | RC },
+	{ .ca_id = 0x07, .n_ch = 8,
+	  .mask = FL | FR | LFE | FC | RC },
+	{ .ca_id = 0x0c, .n_ch = 8,
+	  .mask = FL | FR | RC | RL | RR },
+	{ .ca_id = 0x0d, .n_ch = 8,
+	  .mask = FL | FR | LFE | RL | RR | RC },
+	{ .ca_id = 0x0e, .n_ch = 8,
+	  .mask = FL | FR | FC | RL | RR | RC },
+	{ .ca_id = 0x10, .n_ch = 8,
+	  .mask = FL | FR | RL | RR | RLC | RRC },
+	{ .ca_id = 0x11, .n_ch = 8,
+	  .mask = FL | FR | LFE | RL | RR | RLC | RRC },
+	{ .ca_id = 0x12, .n_ch = 8,
+	  .mask = FL | FR | FC | RL | RR | RLC | RRC },
+	{ .ca_id = 0x14, .n_ch = 8,
+	  .mask = FL | FR | FLC | FRC },
+	{ .ca_id = 0x15, .n_ch = 8,
+	  .mask = FL | FR | LFE | FLC | FRC },
+	{ .ca_id = 0x16, .n_ch = 8,
+	  .mask = FL | FR | FC | FLC | FRC },
+	{ .ca_id = 0x17, .n_ch = 8,
+	  .mask = FL | FR | LFE | FC | FLC | FRC },
+	{ .ca_id = 0x18, .n_ch = 8,
+	  .mask = FL | FR | RC | FLC | FRC },
+	{ .ca_id = 0x19, .n_ch = 8,
+	  .mask = FL | FR | LFE | RC | FLC | FRC },
+	{ .ca_id = 0x1a, .n_ch = 8,
+	  .mask = FL | FR | RC | FC | FLC | FRC },
+	{ .ca_id = 0x1b, .n_ch = 8,
+	  .mask = FL | FR | LFE | RC | FC | FLC | FRC },
+	{ .ca_id = 0x1c, .n_ch = 8,
+	  .mask = FL | FR | RL | RR | FLC | FRC },
+	{ .ca_id = 0x1d, .n_ch = 8,
+	  .mask = FL | FR | LFE | RL | RR | FLC | FRC },
+	{ .ca_id = 0x1e, .n_ch = 8,
+	  .mask = FL | FR | FC | RL | RR | FLC | FRC },
+	{ .ca_id = 0x1f, .n_ch = 8,
+	  .mask = FL | FR | LFE | FC | RL | RR | FLC | FRC },
+};
+
 struct hdmi_codec_priv {
 	struct hdmi_codec_pdata hcd;
 	struct snd_soc_dai_driver *daidrv;
@@ -41,6 +294,8 @@ 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_pcm_chmap *chmap_info;
+	unsigned int chmap_idx;
 };
 
 static const struct snd_soc_dapm_widget hdmi_widgets[] = {
@@ -79,6 +334,83 @@ static int hdmi_eld_ctl_get(struct snd_kcontrol *kcontrol,
 	return 0;
 }
 
+static unsigned long hdmi_codec_spk_mask_from_alloc(int spk_alloc)
+{
+	int i;
+	const unsigned long hdmi_codec_eld_spk_alloc_bits[] = {
+		[0] = FL | FR, [1] = LFE, [2] = FC, [3] = RL | RR,
+		[4] = RC, [5] = FLC | FRC, [6] = RLC | RRC,
+	};
+	unsigned long spk_mask = 0;
+
+	for (i = 0; i < ARRAY_SIZE(hdmi_codec_eld_spk_alloc_bits); i++) {
+		if (spk_alloc & (1 << i))
+			spk_mask |= hdmi_codec_eld_spk_alloc_bits[i];
+	}
+
+	return spk_mask;
+}
+
+void hdmi_codec_eld_chmap(struct hdmi_codec_priv *hcp)
+{
+	u8 spk_alloc;
+	unsigned long spk_mask;
+
+	spk_alloc = drm_eld_get_spk_alloc(hcp->eld);
+	spk_mask = hdmi_codec_spk_mask_from_alloc(spk_alloc);
+
+	/* Detect if only stereo supported, else return 8 channels mappings */
+	if ((spk_mask & ~(FL | FR)) && hcp->chmap_info->max_channels > 2)
+		hcp->chmap_info->chmap = hdmi_codec_8ch_chmaps;
+	else
+		hcp->chmap_info->chmap = hdmi_codec_stereo_chmaps;
+}
+
+static int hdmi_codec_get_ch_alloc_table_idx(struct hdmi_codec_priv *hcp,
+					     unsigned char channels)
+{
+	int i;
+	u8 spk_alloc;
+	unsigned long spk_mask;
+	const struct hdmi_codec_cea_spk_alloc *cap = hdmi_codec_channel_alloc;
+
+	spk_alloc = drm_eld_get_spk_alloc(hcp->eld);
+	spk_mask = hdmi_codec_spk_mask_from_alloc(spk_alloc);
+
+	for (i = 0; i < ARRAY_SIZE(hdmi_codec_channel_alloc); i++, cap++) {
+		/* If spk_alloc == 0, HDMI is unplugged return stereo config*/
+		if (!spk_alloc && cap->ca_id == 0)
+			return i;
+		if (cap->n_ch != channels)
+			continue;
+		if (!(cap->mask == (spk_mask & cap->mask)))
+			continue;
+		return i;
+	}
+
+	return -EINVAL;
+}
+static int hdmi_codec_chmap_ctl_get(struct snd_kcontrol *kcontrol,
+			      struct snd_ctl_elem_value *ucontrol)
+{
+	unsigned const char *map;
+	unsigned int i;
+	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
+	struct hdmi_codec_priv *hcp = info->private_data;
+
+	map = info->chmap[hcp->chmap_idx].map;
+
+	for (i = 0; i < info->max_channels; i++) {
+		if (hcp->chmap_idx == HDMI_CODEC_CHMAP_IDX_UNKNOWN)
+			ucontrol->value.integer.value[i] = 0;
+		else
+			ucontrol->value.integer.value[i] = map[i];
+	}
+
+	return 0;
+}
+
+
 static const struct snd_kcontrol_new hdmi_controls[] = {
 	{
 		.access = SNDRV_CTL_ELEM_ACCESS_READ |
@@ -140,6 +472,8 @@ static int hdmi_codec_startup(struct snd_pcm_substream *substream,
 			if (ret)
 				return ret;
 		}
+		/* Select chmap supported */
+		hdmi_codec_eld_chmap(hcp);
 	}
 	return 0;
 }
@@ -153,6 +487,7 @@ static void hdmi_codec_shutdown(struct snd_pcm_substream *substream,
 
 	WARN_ON(hcp->current_stream != substream);
 
+	hcp->chmap_idx = HDMI_CODEC_CHMAP_IDX_UNKNOWN;
 	hcp->hcd.ops->audio_shutdown(dai->dev->parent, hcp->hcd.data);
 
 	mutex_lock(&hcp->current_stream_lock);
@@ -173,7 +508,7 @@ static int hdmi_codec_hw_params(struct snd_pcm_substream *substream,
 			.dig_subframe = { 0 },
 		}
 	};
-	int ret;
+	int ret, idx;
 
 	dev_dbg(dai->dev, "%s() width %d rate %d channels %d\n", __func__,
 		params_width(params), params_rate(params),
@@ -200,6 +535,17 @@ static int hdmi_codec_hw_params(struct snd_pcm_substream *substream,
 	hp.cea.sample_size = HDMI_AUDIO_SAMPLE_SIZE_STREAM;
 	hp.cea.sample_frequency = HDMI_AUDIO_SAMPLE_FREQUENCY_STREAM;
 
+	/* Select a channel allocation that matches with ELD and pcm channels */
+	idx = hdmi_codec_get_ch_alloc_table_idx(hcp, hp.cea.channels);
+	if (idx < 0) {
+		dev_err(dai->dev, "Not able to map channels to speakers (%d)\n",
+			idx);
+		hcp->chmap_idx = HDMI_CODEC_CHMAP_IDX_UNKNOWN;
+		return idx;
+	}
+	hp.cea.channel_allocation = hdmi_codec_channel_alloc[idx].ca_id;
+	hcp->chmap_idx = hdmi_codec_channel_alloc[idx].ca_id;
+
 	hp.sample_width = params_width(params);
 	hp.sample_rate = params_rate(params);
 	hp.channels = params_channels(params);
@@ -328,6 +674,32 @@ static const struct snd_soc_dai_ops hdmi_dai_ops = {
 			 SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S24_BE |\
 			 SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S32_BE)
 
+static int hdmi_codec_pcm_new(struct snd_soc_pcm_runtime *rtd,
+			      struct snd_soc_dai *dai)
+{
+	struct snd_soc_dai_driver *drv = dai->driver;
+	struct hdmi_codec_priv *hcp = snd_soc_dai_get_drvdata(dai);
+	int ret;
+
+	dev_dbg(dai->dev, "%s()\n", __func__);
+
+	ret =  snd_pcm_add_chmap_ctls(rtd->pcm, SNDRV_PCM_STREAM_PLAYBACK,
+				      NULL, drv->playback.channels_max, 0,
+				      &hcp->chmap_info);
+	if (ret < 0)
+		return ret;
+
+	/* override handlers */
+	hcp->chmap_info->private_data = hcp;
+	hcp->chmap_info->kctl->get = hdmi_codec_chmap_ctl_get;
+
+	/* default chmap supported is stereo */
+	hcp->chmap_info->chmap = hdmi_codec_stereo_chmaps;
+	hcp->chmap_idx = HDMI_CODEC_CHMAP_IDX_UNKNOWN;
+
+	return 0;
+}
+
 static struct snd_soc_dai_driver hdmi_i2s_dai = {
 	.id = DAI_ID_I2S,
 	.playback = {
@@ -339,6 +711,7 @@ static struct snd_soc_dai_driver hdmi_i2s_dai = {
 		.sig_bits = 24,
 	},
 	.ops = &hdmi_dai_ops,
+	.pcm_new = hdmi_codec_pcm_new,
 };
 
 static const struct snd_soc_dai_driver hdmi_spdif_dai = {
@@ -351,6 +724,7 @@ static const struct snd_soc_dai_driver hdmi_spdif_dai = {
 		.formats = SPDIF_FORMATS,
 	},
 	.ops = &hdmi_dai_ops,
+	.pcm_new = hdmi_codec_pcm_new,
 };
 
 static char hdmi_dai_name[][DAI_NAME_SIZE] = {
@@ -479,6 +853,10 @@ static int hdmi_codec_probe(struct platform_device *pdev)
 
 static int hdmi_codec_remove(struct platform_device *pdev)
 {
+	struct hdmi_codec_priv *hcp;
+
+	hcp = dev_get_drvdata(&pdev->dev);
+	kfree(hcp->chmap_info);
 	snd_soc_unregister_codec(&pdev->dev);
 	return 0;
 }