[PATCH 3/3] ASoC: tlv320aic3x: switch to using gpiod API

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

Switch the driver from legacy gpio API that is deprecated to the newer
gpiod API that respects line polarities described in ACPI/DT.

The driver still tries to support shared reset lines, by first trying to
allocate the reset GPIO normally, and then non-exclusively, although the
utility of such support is questionable, toggling reset line from one
driver/instance will result in all chips being reset, potentially at an
inopportune moment.

Note that this change depends on commit fbbbcd177a27 ("gpiolib: of: add
quirk for locating reset lines with legacy bindings") to translate
request for "reset" GPIO to the legacy name "gpio-reset" in case when
proper name is not used.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 sound/soc/codecs/tlv320aic3x.c | 108 ++++++++++++---------------------
 1 file changed, 39 insertions(+), 69 deletions(-)

diff --git a/sound/soc/codecs/tlv320aic3x.c b/sound/soc/codecs/tlv320aic3x.c
index 9b2bb99cc165..56e795a00e22 100644
--- a/sound/soc/codecs/tlv320aic3x.c
+++ b/sound/soc/codecs/tlv320aic3x.c
@@ -32,12 +32,12 @@
 #include <linux/moduleparam.h>
 #include <linux/init.h>
 #include <linux/delay.h>
+#include <linux/err.h>
 #include <linux/pm.h>
 #include <linux/i2c.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/regulator/consumer.h>
 #include <linux/of.h>
-#include <linux/of_gpio.h>
 #include <linux/slab.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
@@ -56,8 +56,6 @@ static const char *aic3x_supply_names[AIC3X_NUM_SUPPLIES] = {
 	"DRVDD",	/* ADC Analog and Output Driver Voltage */
 };
 
-static LIST_HEAD(reset_list);
-
 struct aic3x_priv;
 
 struct aic3x_disable_nb {
@@ -80,9 +78,9 @@ struct aic3x_priv {
 	unsigned int dai_fmt;
 	unsigned int tdm_delay;
 	unsigned int slot_width;
-	struct list_head list;
 	int master;
-	int gpio_reset;
+	struct gpio_desc *gpio_reset;
+	bool shared_reset;
 	int power;
 	u16 model;
 
@@ -1369,8 +1367,8 @@ static int aic3x_regulator_event(struct notifier_block *nb,
 		 * Put codec to reset and require cache sync as at least one
 		 * of the supplies was disabled
 		 */
-		if (gpio_is_valid(aic3x->gpio_reset))
-			gpio_set_value(aic3x->gpio_reset, 0);
+		if (aic3x->gpio_reset)
+			gpiod_set_value(aic3x->gpio_reset, 1);
 		regcache_mark_dirty(aic3x->regmap);
 	}
 
@@ -1390,9 +1388,9 @@ static int aic3x_set_power(struct snd_soc_component *component, int power)
 			goto out;
 		aic3x->power = 1;
 
-		if (gpio_is_valid(aic3x->gpio_reset)) {
+		if (aic3x->gpio_reset) {
 			udelay(1);
-			gpio_set_value(aic3x->gpio_reset, 1);
+			gpiod_set_value(aic3x->gpio_reset, 0);
 		}
 
 		/* Sync reg_cache with the hardware */
@@ -1598,19 +1596,6 @@ static int aic3x_init(struct snd_soc_component *component)
 	return 0;
 }
 
-static bool aic3x_is_shared_reset(struct aic3x_priv *aic3x)
-{
-	struct aic3x_priv *a;
-
-	list_for_each_entry(a, &reset_list, list) {
-		if (gpio_is_valid(aic3x->gpio_reset) &&
-		    aic3x->gpio_reset == a->gpio_reset)
-			return true;
-	}
-
-	return false;
-}
-
 static int aic3x_component_probe(struct snd_soc_component *component)
 {
 	struct aic3x_priv *aic3x = snd_soc_component_get_drvdata(component);
@@ -1775,19 +1760,6 @@ int aic3x_probe(struct device *dev, struct regmap *regmap, kernel_ulong_t driver
 		if (!ai3x_setup)
 			return -ENOMEM;
 
-		ret = of_get_named_gpio(np, "reset-gpios", 0);
-		if (ret >= 0) {
-			aic3x->gpio_reset = ret;
-		} else {
-			ret = of_get_named_gpio(np, "gpio-reset", 0);
-			if (ret > 0) {
-				dev_warn(dev, "Using deprecated property \"gpio-reset\", please update your DT");
-				aic3x->gpio_reset = ret;
-			} else {
-				aic3x->gpio_reset = -1;
-			}
-		}
-
 		if (of_property_read_u32_array(np, "ai3x-gpio-func",
 					ai3x_setup->gpio_func, 2) >= 0) {
 			aic3x->setup = ai3x_setup;
@@ -1812,29 +1784,43 @@ int aic3x_probe(struct device *dev, struct regmap *regmap, kernel_ulong_t driver
 		} else {
 			aic3x->micbias_vg = AIC3X_MICBIAS_OFF;
 		}
-
-	} else {
-		aic3x->gpio_reset = -1;
 	}
 
 	aic3x->model = driver_data;
 
-	if (gpio_is_valid(aic3x->gpio_reset) &&
-	    !aic3x_is_shared_reset(aic3x)) {
-		ret = gpio_request(aic3x->gpio_reset, "tlv320aic3x reset");
-		if (ret != 0)
-			goto err;
-		gpio_direction_output(aic3x->gpio_reset, 0);
+	aic3x->gpio_reset = devm_gpiod_get_optional(dev, "reset",
+						    GPIOD_OUT_HIGH);
+	ret = PTR_ERR_OR_ZERO(aic3x->gpio_reset);
+	if (ret) {
+		if (ret != -EBUSY)
+			return ret;
+
+		/*
+		 * Apparently there are setups where the codec is sharing
+		 * its reset line. Try to get it non-exclusively, although
+		 * the utility of this is unclear: how do we make sure that
+		 * resetting one chip will not disturb the others that share
+		 * the same line?
+		 */
+		aic3x->gpio_reset = devm_gpiod_get(dev, "reset",
+				GPIOD_ASIS | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
+		ret = PTR_ERR_OR_ZERO(aic3x->gpio_reset);
+		if (ret)
+			return ret;
+
+		aic3x->shared_reset = true;
 	}
 
+	gpiod_set_consumer_name(aic3x->gpio_reset, "tlv320aic3x reset");
+
 	for (i = 0; i < ARRAY_SIZE(aic3x->supplies); i++)
 		aic3x->supplies[i].supply = aic3x_supply_names[i];
 
 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(aic3x->supplies),
 				      aic3x->supplies);
-	if (ret != 0) {
+	if (ret) {
 		dev_err(dev, "Failed to request supplies: %d\n", ret);
-		goto err_gpio;
+		return ret;
 	}
 
 	aic3x_configure_ocmv(dev, aic3x);
@@ -1843,26 +1829,14 @@ int aic3x_probe(struct device *dev, struct regmap *regmap, kernel_ulong_t driver
 		ret = regmap_register_patch(aic3x->regmap, aic3007_class_d,
 					    ARRAY_SIZE(aic3007_class_d));
 		if (ret != 0)
-			dev_err(dev, "Failed to init class D: %d\n",
-				ret);
+			dev_err(dev, "Failed to init class D: %d\n", ret);
 	}
 
 	ret = devm_snd_soc_register_component(dev, &soc_component_dev_aic3x, &aic3x_dai, 1);
-
-	if (ret != 0)
-		goto err_gpio;
-
-	INIT_LIST_HEAD(&aic3x->list);
-	list_add(&aic3x->list, &reset_list);
+	if (ret)
+		return ret;
 
 	return 0;
-
-err_gpio:
-	if (gpio_is_valid(aic3x->gpio_reset) &&
-	    !aic3x_is_shared_reset(aic3x))
-		gpio_free(aic3x->gpio_reset);
-err:
-	return ret;
 }
 EXPORT_SYMBOL(aic3x_probe);
 
@@ -1870,13 +1844,9 @@ void aic3x_remove(struct device *dev)
 {
 	struct aic3x_priv *aic3x = dev_get_drvdata(dev);
 
-	list_del(&aic3x->list);
-
-	if (gpio_is_valid(aic3x->gpio_reset) &&
-	    !aic3x_is_shared_reset(aic3x)) {
-		gpio_set_value(aic3x->gpio_reset, 0);
-		gpio_free(aic3x->gpio_reset);
-	}
+	/* Leave the codec in reset state */
+	if (aic3x->gpio_reset && !aic3x->shared_reset)
+		gpiod_set_value(aic3x->gpio_reset, 1);
 }
 EXPORT_SYMBOL(aic3x_remove);
 
-- 
2.38.1.273.g43a17bfeac-goog