iio: st_sensors: move regulator retrieveal to core

Currently the pressure sensor has code to retrieve and enable two
regulators for Vdd and Vdd IO, but actually these voltage inputs
are found on all of these ST sensors, so move the regulator
handling to the core and make sure all the ST sensors call these
functions on probe() and remove() to enable/disable power.

Here also mover over to obtaining the regulator from the *parent*
device of the IIO device, as the IIO device is created on-the-fly
in this very subsystem it very unlikely evert have any regulators
attached to it whatsoever. It is much more likely that the parent
is a platform device, possibly instantiated from a device tree,
which in turn have Vdd and Vdd IO supplied assigned to it.

Cc: Lee Jones <lee.jones@linaro.org>
Cc: Denis CIOCCA <denis.ciocca@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/accel/st_accel_core.c

@@ -459,6 +459,8 @@ int st_accel_common_probe(struct iio_dev *indio_dev,
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &accel_info;
 
+	st_sensors_power_enable(indio_dev);
+
 	err = st_sensors_check_device_support(indio_dev,
 				ARRAY_SIZE(st_accel_sensors), st_accel_sensors);
 	if (err < 0)
@@ -515,6 +517,8 @@ void st_accel_common_remove(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *adata = iio_priv(indio_dev);
 
+	st_sensors_power_disable(indio_dev);
+
 	iio_device_unregister(indio_dev);
 	if (adata->get_irq_data_ready(indio_dev) > 0)
 		st_sensors_deallocate_trigger(indio_dev);

drivers/iio/common/st_sensors/st_sensors_core.c

@@ -13,6 +13,7 @@
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/iio/iio.h>
+#include <linux/regulator/consumer.h>
 #include <asm/unaligned.h>
 
 #include <linux/iio/common/st_sensors.h>
@@ -198,6 +199,42 @@ int st_sensors_set_axis_enable(struct iio_dev *indio_dev, u8 axis_enable)
 }
 EXPORT_SYMBOL(st_sensors_set_axis_enable);
 
+void st_sensors_power_enable(struct iio_dev *indio_dev)
+{
+	struct st_sensor_data *pdata = iio_priv(indio_dev);
+	int err;
+
+	/* Regulators not mandatory, but if requested we should enable them. */
+	pdata->vdd = devm_regulator_get_optional(indio_dev->dev.parent, "vdd");
+	if (!IS_ERR(pdata->vdd)) {
+		err = regulator_enable(pdata->vdd);
+		if (err != 0)
+			dev_warn(&indio_dev->dev,
+				 "Failed to enable specified Vdd supply\n");
+	}
+
+	pdata->vdd_io = devm_regulator_get_optional(indio_dev->dev.parent, "vddio");
+	if (!IS_ERR(pdata->vdd_io)) {
+		err = regulator_enable(pdata->vdd_io);
+		if (err != 0)
+			dev_warn(&indio_dev->dev,
+				 "Failed to enable specified Vdd_IO supply\n");
+	}
+}
+EXPORT_SYMBOL(st_sensors_power_enable);
+
+void st_sensors_power_disable(struct iio_dev *indio_dev)
+{
+	struct st_sensor_data *pdata = iio_priv(indio_dev);
+
+	if (!IS_ERR(pdata->vdd))
+		regulator_disable(pdata->vdd);
+
+	if (!IS_ERR(pdata->vdd_io))
+		regulator_disable(pdata->vdd_io);
+}
+EXPORT_SYMBOL(st_sensors_power_disable);
+
 static int st_sensors_set_drdy_int_pin(struct iio_dev *indio_dev,
 				       struct st_sensors_platform_data *pdata)
 {

drivers/iio/gyro/st_gyro_core.c

@@ -311,6 +311,8 @@ int st_gyro_common_probe(struct iio_dev *indio_dev,
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &gyro_info;
 
+	st_sensors_power_enable(indio_dev);
+
 	err = st_sensors_check_device_support(indio_dev,
 				ARRAY_SIZE(st_gyro_sensors), st_gyro_sensors);
 	if (err < 0)
@@ -363,6 +365,8 @@ void st_gyro_common_remove(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *gdata = iio_priv(indio_dev);
 
+	st_sensors_power_disable(indio_dev);
+
 	iio_device_unregister(indio_dev);
 	if (gdata->get_irq_data_ready(indio_dev) > 0)
 		st_sensors_deallocate_trigger(indio_dev);

drivers/iio/magnetometer/st_magn_core.c

@@ -355,6 +355,8 @@ int st_magn_common_probe(struct iio_dev *indio_dev,
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &magn_info;
 
+	st_sensors_power_enable(indio_dev);
+
 	err = st_sensors_check_device_support(indio_dev,
 				ARRAY_SIZE(st_magn_sensors), st_magn_sensors);
 	if (err < 0)
@@ -406,6 +408,8 @@ void st_magn_common_remove(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *mdata = iio_priv(indio_dev);
 
+	st_sensors_power_disable(indio_dev);
+
 	iio_device_unregister(indio_dev);
 	if (mdata->get_irq_data_ready(indio_dev) > 0)
 		st_sensors_deallocate_trigger(indio_dev);

drivers/iio/pressure/st_pressure_core.c

@@ -23,7 +23,6 @@
 #include <linux/iio/sysfs.h>
 #include <linux/iio/trigger.h>
 #include <linux/iio/buffer.h>
-#include <linux/regulator/consumer.h>
 #include <asm/unaligned.h>
 
 #include <linux/iio/common/st_sensors.h>
@@ -387,40 +386,6 @@ static const struct iio_trigger_ops st_press_trigger_ops = {
 #define ST_PRESS_TRIGGER_OPS NULL
 #endif
 
-static void st_press_power_enable(struct iio_dev *indio_dev)
-{
-	struct st_sensor_data *pdata = iio_priv(indio_dev);
-	int err;
-
-	/* Regulators not mandatory, but if requested we should enable them. */
-	pdata->vdd = devm_regulator_get_optional(&indio_dev->dev, "vdd");
-	if (!IS_ERR(pdata->vdd)) {
-		err = regulator_enable(pdata->vdd);
-		if (err != 0)
-			dev_warn(&indio_dev->dev,
-				 "Failed to enable specified Vdd supply\n");
-	}
-
-	pdata->vdd_io = devm_regulator_get_optional(&indio_dev->dev, "vddio");
-	if (!IS_ERR(pdata->vdd_io)) {
-		err = regulator_enable(pdata->vdd_io);
-		if (err != 0)
-			dev_warn(&indio_dev->dev,
-				 "Failed to enable specified Vdd_IO supply\n");
-	}
-}
-
-static void st_press_power_disable(struct iio_dev *indio_dev)
-{
-	struct st_sensor_data *pdata = iio_priv(indio_dev);
-
-	if (!IS_ERR(pdata->vdd))
-		regulator_disable(pdata->vdd);
-
-	if (!IS_ERR(pdata->vdd_io))
-		regulator_disable(pdata->vdd_io);
-}
-
 int st_press_common_probe(struct iio_dev *indio_dev,
 				struct st_sensors_platform_data *plat_data)
 {
@@ -431,7 +396,7 @@ int st_press_common_probe(struct iio_dev *indio_dev,
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->info = &press_info;
 
-	st_press_power_enable(indio_dev);
+	st_sensors_power_enable(indio_dev);
 
 	err = st_sensors_check_device_support(indio_dev,
 					      ARRAY_SIZE(st_press_sensors),
@@ -493,7 +458,7 @@ void st_press_common_remove(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *pdata = iio_priv(indio_dev);
 
-	st_press_power_disable(indio_dev);
+	st_sensors_power_disable(indio_dev);
 
 	iio_device_unregister(indio_dev);
 	if (pdata->get_irq_data_ready(indio_dev) > 0)

include/linux/iio/common/st_sensors.h

@@ -269,6 +269,10 @@ int st_sensors_set_enable(struct iio_dev *indio_dev, bool enable);
 
 int st_sensors_set_axis_enable(struct iio_dev *indio_dev, u8 axis_enable);
 
+void st_sensors_power_enable(struct iio_dev *indio_dev);
+
+void st_sensors_power_disable(struct iio_dev *indio_dev);
+
 int st_sensors_set_odr(struct iio_dev *indio_dev, unsigned int odr);
 
 int st_sensors_set_dataready_irq(struct iio_dev *indio_dev, bool enable);