[PATCH v6 5/6] ASoC: codecs: wcd938x: add mux control support for hp audio mux

[srinivas . kandagatla]

From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>

On some platforms to minimise pop and click during switching between
CTIA and OMTP headset an additional HiFi mux is used. Most common
case is that this switch is switched on by default, but on some
platforms this needs a regulator enable.

move to using mux control to enable both regulator and handle gpios,
deprecate the usage of gpio.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Tested-by: Christopher Obbard <christopher.obbard@xxxxxxxxxx>
---
 sound/soc/codecs/Kconfig   |  1 +
 sound/soc/codecs/wcd938x.c | 55 ++++++++++++++++++++++++++++++--------
 2 files changed, 45 insertions(+), 11 deletions(-)

diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index ee35f3aa5521..a2829d76e108 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -2226,6 +2226,7 @@ config SND_SOC_WCD938X
 	tristate
 	depends on SOUNDWIRE || !SOUNDWIRE
 	select SND_SOC_WCD_CLASSH
+	select MULTIPLEXER
 
 config SND_SOC_WCD938X_SDW
 	tristate "WCD9380/WCD9385 Codec - SDW"
diff --git a/sound/soc/codecs/wcd938x.c b/sound/soc/codecs/wcd938x.c
index dfaa3de31164..d588ab3546d5 100644
--- a/sound/soc/codecs/wcd938x.c
+++ b/sound/soc/codecs/wcd938x.c
@@ -19,6 +19,7 @@
 #include <linux/regmap.h>
 #include <sound/soc.h>
 #include <sound/soc-dapm.h>
+#include <linux/mux/consumer.h>
 #include <linux/regulator/consumer.h>
 
 #include "wcd-clsh-v2.h"
@@ -178,6 +179,8 @@ struct wcd938x_priv {
 	int variant;
 	int reset_gpio;
 	struct gpio_desc *us_euro_gpio;
+	struct mux_control *us_euro_mux;
+	unsigned int mux_state;
 	u32 micb1_mv;
 	u32 micb2_mv;
 	u32 micb3_mv;
@@ -188,6 +191,7 @@ struct wcd938x_priv {
 	bool comp1_enable;
 	bool comp2_enable;
 	bool ldoh;
+	bool mux_setup_done;
 };
 
 static const SNDRV_CTL_TLVD_DECLARE_DB_MINMAX(ear_pa_gain, 600, -1800);
@@ -3237,15 +3241,26 @@ static void wcd938x_dt_parse_micbias_info(struct device *dev, struct wcd938x_pri
 
 static bool wcd938x_swap_gnd_mic(struct snd_soc_component *component)
 {
-	int value;
-
-	struct wcd938x_priv *wcd938x;
+	struct wcd938x_priv *wcd938x = snd_soc_component_get_drvdata(component);
+	struct device *dev = component->dev;
+	int ret;
 
-	wcd938x = snd_soc_component_get_drvdata(component);
+	if (wcd938x->us_euro_mux) {
+		if (wcd938x->mux_setup_done)
+			mux_control_deselect(wcd938x->us_euro_mux);
 
-	value = gpiod_get_value(wcd938x->us_euro_gpio);
+		ret = mux_control_try_select(wcd938x->us_euro_mux, !wcd938x->mux_state);
+		if (ret) {
+			dev_err(dev, "Error (%d) Unable to select us/euro mux state\n", ret);
+			wcd938x->mux_setup_done = false;
+			return false;
+		}
+		wcd938x->mux_setup_done = true;
+	} else {
+		gpiod_set_value(wcd938x->us_euro_gpio, !wcd938x->mux_state);
+	}
 
-	gpiod_set_value(wcd938x->us_euro_gpio, !value);
+	wcd938x->mux_state = !wcd938x->mux_state;
 
 	return true;
 }
@@ -3261,11 +3276,26 @@ static int wcd938x_populate_dt_data(struct wcd938x_priv *wcd938x, struct device
 		return dev_err_probe(dev, wcd938x->reset_gpio,
 				     "Failed to get reset gpio\n");
 
-	wcd938x->us_euro_gpio = devm_gpiod_get_optional(dev, "us-euro",
-						GPIOD_OUT_LOW);
-	if (IS_ERR(wcd938x->us_euro_gpio))
-		return dev_err_probe(dev, PTR_ERR(wcd938x->us_euro_gpio),
-				     "us-euro swap Control GPIO not found\n");
+	wcd938x->us_euro_mux = devm_mux_control_get(dev, NULL);
+	if (IS_ERR(wcd938x->us_euro_mux)) {
+		if (PTR_ERR(wcd938x->us_euro_mux) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+
+		/* mux is optional and now fallback to using gpio */
+		wcd938x->us_euro_mux = NULL;
+		wcd938x->us_euro_gpio = devm_gpiod_get_optional(dev, "us-euro", GPIOD_OUT_LOW);
+		if (IS_ERR(wcd938x->us_euro_gpio))
+			return dev_err_probe(dev, PTR_ERR(wcd938x->us_euro_gpio),
+					     "us-euro swap Control GPIO not found\n");
+	} else {
+		ret = mux_control_try_select(wcd938x->us_euro_mux, wcd938x->mux_state);
+		if (ret) {
+			dev_err(dev, "Error (%d) Unable to select us/euro mux state\n", ret);
+			wcd938x->mux_setup_done = false;
+			return ret;
+		}
+		wcd938x->mux_setup_done = true;
+	}
 
 	cfg->swap_gnd_mic = wcd938x_swap_gnd_mic;
 
@@ -3581,6 +3611,9 @@ static void wcd938x_remove(struct platform_device *pdev)
 	pm_runtime_set_suspended(dev);
 	pm_runtime_dont_use_autosuspend(dev);
 
+	if (wcd938x->us_euro_mux && wcd938x->mux_setup_done)
+		mux_control_deselect(wcd938x->us_euro_mux);
+
 	regulator_bulk_disable(WCD938X_MAX_SUPPLY, wcd938x->supplies);
 	regulator_bulk_free(WCD938X_MAX_SUPPLY, wcd938x->supplies);
 }
-- 
2.39.5