3 files changed, 54 insertions, 0 deletions

diff --git a/sound/soc/tegra/tegra_i2s.c b/sound/soc/tegra/tegra_i2s.c
index 83dc452f000c..e4dc4e3c8c19 100644
--- a/sound/soc/tegra/tegra_i2s.c
+++ b/sound/soc/tegra/tegra_i2s.c
@@ -32,6 +32,8 @@ struct tegra_i2s_info {
 	struct das_regs_cache das_regs;
 };
 
+extern int tegra_i2sloopback_func;
+
 void free_i2s_dma_request(struct snd_pcm_substream *substream)
 {
 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
@@ -154,6 +156,11 @@ static int tegra_i2s_hw_params(struct snd_pcm_substream *substream,
 	}
 	i2s_set_bit_size(i2s_id, val);
 
+	if (tegra_i2sloopback_func == TEGRA_INT_I2SLOOPBACK_ON)
+		i2s_set_loopback(i2s_id,1);
+	else
+		i2s_set_loopback(i2s_id,0);
+
 	switch (params_rate(params)) {
 	case 8000:
 	case 32000:
diff --git a/sound/soc/tegra/tegra_soc.h b/sound/soc/tegra/tegra_soc.h
index 53366d33b090..4b839e33bf0e 100644
--- a/sound/soc/tegra/tegra_soc.h
+++ b/sound/soc/tegra/tegra_soc.h
@@ -70,6 +70,8 @@
 #define I2S1_CLK 		11289600
 #define I2S2_CLK 		2000000
 #define TEGRA_DEFAULT_SR	44100
+#define TEGRA_INT_I2SLOOPBACK_ON	1
+#define TEGRA_INT_I2SLOOPBACK_OFF	0
 
 #define TEGRA_SAMPLE_RATES (SNDRV_PCM_RATE_8000_96000)
 #define TEGRA_VOICE_SAMPLE_RATES SNDRV_PCM_RATE_8000
diff --git a/sound/soc/tegra/tegra_soc_controls.c b/sound/soc/tegra/tegra_soc_controls.c
index c430703f4bd4..90e8679d4dec 100644
--- a/sound/soc/tegra/tegra_soc_controls.c
+++ b/sound/soc/tegra/tegra_soc_controls.c
@@ -20,6 +20,8 @@
 
 #include "tegra_soc.h"
 
+int tegra_i2sloopback_func = TEGRA_INT_I2SLOOPBACK_OFF;
+
 static void tegra_audio_route(struct tegra_audio_data* audio_data,
 			      int device_new, int is_call_mode_new)
 {
@@ -260,6 +262,43 @@ struct snd_kcontrol_new tegra_call_mode_control = {
 	.put = tegra_call_mode_put
 };
 
+static int tegra_i2s_loopback_info(struct snd_kcontrol *kcontrol,
+				struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+	uinfo->count = 1;
+	uinfo->value.integer.min = 0;
+	uinfo->value.integer.max = 1;
+	return 0;
+}
+
+static int tegra_i2s_loopback_get(struct snd_kcontrol *kcontrol,
+				struct snd_ctl_elem_value *ucontrol)
+{
+	ucontrol->value.integer.value[0] = tegra_i2sloopback_func;
+	return 0;
+}
+
+static int tegra_i2s_loopback_put(struct snd_kcontrol *kcontrol,
+				   struct snd_ctl_elem_value *ucontrol)
+{
+	if (tegra_i2sloopback_func == ucontrol->value.integer.value[0])
+	return 0;
+
+	tegra_i2sloopback_func = ucontrol->value.integer.value[0];
+	return 1;
+}
+
+struct snd_kcontrol_new tegra_i2s_loopback_control = {
+	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
+	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+	.name = "I2S loopback",
+	.private_value = 0xffff,
+	.info = tegra_i2s_loopback_info,
+	.get = tegra_i2s_loopback_get,
+	.put = tegra_i2s_loopback_put
+};
+
 int tegra_controls_init(struct snd_soc_codec *codec)
 {
 	struct tegra_audio_data* audio_data = codec->socdev->codec_data;
@@ -283,5 +322,11 @@ int tegra_controls_init(struct snd_soc_codec *codec)
 	if (err < 0)
 		return err;
 
+	/* Add I2S loopback control */
+	err = snd_ctl_add(codec->card,
+		snd_ctl_new1(&tegra_i2s_loopback_control, audio_data));
+	if (err < 0)
+		return err;
+
 	return 0;
 }