ASoC: cs53l30: Add MUTE pin control support via GPIO

The codec chip has a physical MUTE pin to let users control it via
GPIO. So this patch add a mute control support to the driver.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-by: Paul Handrigan <Paul.Handrigan@cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

3 files changed, 35 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/sound/cs53l30.txt b/Documentation/devicetree/bindings/sound/cs53l30.txt
index 18d6b99e0a2d..4dbfb8274cd9 100644
--- a/Documentation/devicetree/bindings/sound/cs53l30.txt
+++ b/Documentation/devicetree/bindings/sound/cs53l30.txt
@@ -13,6 +13,10 @@ Optional properties:
 
   - reset-gpios : a GPIO spec for the reset pin.
 
+  - mute-gpios : a GPIO spec for the MUTE pin. The active state can be either
+                 GPIO_ACTIVE_HIGH or GPIO_ACTIVE_LOW, which would be handled
+                 by the driver automatically.
+
   - cirrus,micbias-lvl : Set the output voltage level on the MICBIAS Pin.
                          0 = Hi-Z
                          1 = 1.80 V
diff --git a/sound/soc/codecs/cs53l30.c b/sound/soc/codecs/cs53l30.c
index b0a64a19a045..5988b5c672fe 100644
--- a/sound/soc/codecs/cs53l30.c
+++ b/sound/soc/codecs/cs53l30.c
@@ -35,6 +35,7 @@ struct cs53l30_private {
         struct regulator_bulk_data      supplies[CS53L30_NUM_SUPPLIES];
         struct regmap                   *regmap;
         struct gpio_desc                *reset_gpio;
+        struct gpio_desc                *mute_gpio;
         struct clk                      *mclk;
         bool                            use_sdout2;
         u32                             mclk_rate;
@@ -833,6 +834,16 @@ static int cs53l30_set_dai_tdm_slot(struct snd_soc_dai *dai,
         return 0;
 }
 
+static int cs53l30_mute_stream(struct snd_soc_dai *dai, int mute, int stream)
+{
+        struct cs53l30_private *priv = snd_soc_codec_get_drvdata(dai->codec);
+
+        if (priv->mute_gpio)
+                gpiod_set_value_cansleep(priv->mute_gpio, mute);
+
+        return 0;
+}
+
 /* SNDRV_PCM_RATE_KNOT -> 12000, 24000 Hz, limit with constraint list */
 #define CS53L30_RATES (SNDRV_PCM_RATE_8000_48000 | SNDRV_PCM_RATE_KNOT)
 
@@ -846,6 +857,7 @@ static const struct snd_soc_dai_ops cs53l30_ops = {
         .set_sysclk = cs53l30_set_sysclk,
         .set_tristate = cs53l30_set_tristate,
         .set_tdm_slot = cs53l30_set_dai_tdm_slot,
+        .mute_stream = cs53l30_mute_stream,
 };
 
 static struct snd_soc_dai_driver cs53l30_dai = {
@@ -991,6 +1003,24 @@ static int cs53l30_i2c_probe(struct i2c_client *client,
                 cs53l30->mclk = NULL;
         }
 
+        /* Fetch the MUTE control */
+        cs53l30->mute_gpio = devm_gpiod_get_optional(dev, "mute",
+                                                     GPIOD_OUT_HIGH);
+        if (IS_ERR(cs53l30->mute_gpio)) {
+                ret = PTR_ERR(cs53l30->mute_gpio);
+                goto error;
+        }
+
+        if (cs53l30->mute_gpio) {
+                /* Enable MUTE controls via MUTE pin */
+                regmap_write(cs53l30->regmap, CS53L30_MUTEP_CTL1,
+                             CS53L30_MUTEP_CTL1_MUTEALL);
+                /* Flip the polarity of MUTE pin */
+                if (gpiod_is_active_low(cs53l30->mute_gpio))
+                        regmap_update_bits(cs53l30->regmap, CS53L30_MUTEP_CTL2,
+                                           CS53L30_MUTE_PIN_POLARITY, 0);
+        }
+
         if (!of_property_read_u8(np, "cirrus,micbias-lvl", &val))
                 regmap_update_bits(cs53l30->regmap, CS53L30_MICBIAS_CTL,
                                    CS53L30_MIC_BIAS_CTRL_MASK, val);
diff --git a/sound/soc/codecs/cs53l30.h b/sound/soc/codecs/cs53l30.h
index 0dd4afbb5c64..5e39da568749 100644
--- a/sound/soc/codecs/cs53l30.h
+++ b/sound/soc/codecs/cs53l30.h
@@ -253,6 +253,7 @@
 #define CS53L30_MUTE_MB_ALL_PDN_MASK    (1 << CS53L30_MUTE_MB_ALL_PDN_SHIFT)
 #define CS53L30_MUTE_MB_ALL_PDN         (1 << CS53L30_MUTE_MB_ALL_PDN_SHIFT)
 
+#define CS53L30_MUTEP_CTL1_MUTEALL      (0xdf)
 #define CS53L30_MUTEP_CTL1_DEFAULT      (0)
 
 /* R32 (0x20) CS53L30_MUTEP_CTL2 - MUTE Pin Control 2 */