ASoC: twl4030: Configure extmute pinmux when the dedicated pin is in use

When HS extmute is enabled without custom GPIO we should configure the mux
to allow the pin to be used as extmute signal.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/twl4030.c

@@ -41,6 +41,11 @@
 /* Register descriptions are here */
 #include <linux/mfd/twl4030-audio.h>
 
+/* TWL4030 PMBR1 Register */
+#define TWL4030_PMBR1_REG		0x0D
+/* TWL4030 PMBR1 Register GPIO6 mux bits */
+#define TWL4030_GPIO6_PWM0_MUTE(value)	((value & 0x03) << 2)
+
 /* Shadow register used by the audio driver */
 #define TWL4030_REG_SW_SHADOW		0x4A
 #define TWL4030_CACHEREGNUM	(TWL4030_REG_SW_SHADOW + 1)
@@ -348,19 +353,32 @@ static void twl4030_init_chip(struct snd_soc_codec *codec)
 
 	pdata = twl4030_get_pdata(codec);
 
-	if (pdata && pdata->hs_extmute &&
-	    gpio_is_valid(pdata->hs_extmute_gpio)) {
-		int ret;
-
-		if (!pdata->hs_extmute_gpio)
-			dev_warn(codec->dev,
-				 "Extmute GPIO is 0 is this correct?\n");
-
-		ret = gpio_request_one(pdata->hs_extmute_gpio,
-				       GPIOF_OUT_INIT_LOW, "hs_extmute");
-		if (ret) {
-			dev_err(codec->dev, "Failed to get hs_extmute GPIO\n");
-			pdata->hs_extmute_gpio = -1;
+	if (pdata && pdata->hs_extmute) {
+		if (gpio_is_valid(pdata->hs_extmute_gpio)) {
+			int ret;
+
+			if (!pdata->hs_extmute_gpio)
+				dev_warn(codec->dev,
+					"Extmute GPIO is 0 is this correct?\n");
+
+			ret = gpio_request_one(pdata->hs_extmute_gpio,
+					       GPIOF_OUT_INIT_LOW,
+					       "hs_extmute");
+			if (ret) {
+				dev_err(codec->dev,
+					"Failed to get hs_extmute GPIO\n");
+				pdata->hs_extmute_gpio = -1;
+			}
+		} else {
+			u8 pin_mux;
+
+			/* Set TWL4030 GPIO6 as EXTMUTE signal */
+			twl_i2c_read_u8(TWL4030_MODULE_INTBR, &pin_mux,
+					TWL4030_PMBR1_REG);
+			pin_mux &= ~TWL4030_GPIO6_PWM0_MUTE(0x03);
+			pin_mux |= TWL4030_GPIO6_PWM0_MUTE(0x02);
+			twl_i2c_write_u8(TWL4030_MODULE_INTBR, pin_mux,
+					 TWL4030_PMBR1_REG);
 		}
 	}