UBUNTU:SAUCE: iio:st_sensors: fix power regulator usage

BugLink: http://bugs.launchpad.net/bugs/1650112

Ensure failure to enable power regulators is properly handled.
Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
(cherry picked from commit 14f295c8)
Signed-off-by: Shrirang Bagul <shrirang.bagul@canonical.com>
Acked-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

drivers/iio/accel/st_accel_core.c

@@ -757,13 +757,15 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
 	indio_dev->info = &accel_info;
 	mutex_init(&adata->tb.buf_lock);
 
-	st_sensors_power_enable(indio_dev);
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
 
 	err = st_sensors_check_device_support(indio_dev,
 					ARRAY_SIZE(st_accel_sensors_settings),
 					st_accel_sensors_settings);
 	if (err < 0)
-		return err;
+		goto st_accel_power_off;
 
 	adata->num_data_channels = ST_ACCEL_NUMBER_DATA_CHANNELS;
 	adata->multiread_bit = adata->sensor_settings->multi_read_bit;
@@ -780,11 +782,11 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
 
 	err = st_sensors_init_sensor(indio_dev, adata->dev->platform_data);
 	if (err < 0)
-		return err;
+		goto st_accel_power_off;
 
 	err = st_accel_allocate_ring(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_accel_power_off;
 
 	if (irq > 0) {
 		err = st_sensors_allocate_trigger(indio_dev,
@@ -807,6 +809,8 @@ int st_accel_common_probe(struct iio_dev *indio_dev)
 		st_sensors_deallocate_trigger(indio_dev);
 st_accel_probe_trigger_error:
 	st_accel_deallocate_ring(indio_dev);
+st_accel_power_off:
+	st_sensors_power_disable(indio_dev);
 
 	return err;
 }

drivers/iio/common/st_sensors/st_sensors_core.c

@@ -228,7 +228,7 @@ 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)
+int st_sensors_power_enable(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *pdata = iio_priv(indio_dev);
 	int err;
@@ -237,18 +237,37 @@ void st_sensors_power_enable(struct iio_dev *indio_dev)
 	pdata->vdd = devm_regulator_get_optional(indio_dev->dev.parent, "vdd");
 	if (!IS_ERR(pdata->vdd)) {
 		err = regulator_enable(pdata->vdd);
-		if (err != 0)
+		if (err != 0) {
 			dev_warn(&indio_dev->dev,
 				 "Failed to enable specified Vdd supply\n");
+			return err;
+		}
+	} else {
+		err = PTR_ERR(pdata->vdd);
+		if (err != -ENODEV)
+			return err;
 	}
 
 	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)
+		if (err != 0) {
 			dev_warn(&indio_dev->dev,
 				 "Failed to enable specified Vdd_IO supply\n");
+			goto st_sensors_disable_vdd;
+		}
+	} else {
+		err = PTR_ERR(pdata->vdd_io);
+		if (err != -ENODEV)
+			goto st_sensors_disable_vdd;
 	}
+
+	return 0;
+
+st_sensors_disable_vdd:
+	if (!IS_ERR_OR_NULL(pdata->vdd))
+		regulator_disable(pdata->vdd);
+	return err;
 }
 EXPORT_SYMBOL(st_sensors_power_enable);
 
@@ -256,10 +275,10 @@ void st_sensors_power_disable(struct iio_dev *indio_dev)
 {
 	struct st_sensor_data *pdata = iio_priv(indio_dev);
 
-	if (!IS_ERR(pdata->vdd))
+	if (!IS_ERR_OR_NULL(pdata->vdd))
 		regulator_disable(pdata->vdd);
 
-	if (!IS_ERR(pdata->vdd_io))
+	if (!IS_ERR_OR_NULL(pdata->vdd_io))
 		regulator_disable(pdata->vdd_io);
 }
 EXPORT_SYMBOL(st_sensors_power_disable);

drivers/iio/gyro/st_gyro_core.c

@@ -424,13 +424,15 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
 	indio_dev->info = &gyro_info;
 	mutex_init(&gdata->tb.buf_lock);
 
-	st_sensors_power_enable(indio_dev);
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
 
 	err = st_sensors_check_device_support(indio_dev,
 					ARRAY_SIZE(st_gyro_sensors_settings),
 					st_gyro_sensors_settings);
 	if (err < 0)
-		return err;
+		goto st_gyro_power_off;
 
 	gdata->num_data_channels = ST_GYRO_NUMBER_DATA_CHANNELS;
 	gdata->multiread_bit = gdata->sensor_settings->multi_read_bit;
@@ -444,11 +446,11 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
 	err = st_sensors_init_sensor(indio_dev,
 				(struct st_sensors_platform_data *)&gyro_pdata);
 	if (err < 0)
-		return err;
+		goto st_gyro_power_off;
 
 	err = st_gyro_allocate_ring(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_gyro_power_off;
 
 	if (irq > 0) {
 		err = st_sensors_allocate_trigger(indio_dev,
@@ -471,6 +473,8 @@ int st_gyro_common_probe(struct iio_dev *indio_dev)
 		st_sensors_deallocate_trigger(indio_dev);
 st_gyro_probe_trigger_error:
 	st_gyro_deallocate_ring(indio_dev);
+st_gyro_power_off:
+	st_sensors_power_disable(indio_dev);
 
 	return err;
 }

drivers/iio/magnetometer/st_magn_core.c

@@ -588,13 +588,15 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
 	indio_dev->info = &magn_info;
 	mutex_init(&mdata->tb.buf_lock);
 
-	st_sensors_power_enable(indio_dev);
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
 
 	err = st_sensors_check_device_support(indio_dev,
 					ARRAY_SIZE(st_magn_sensors_settings),
 					st_magn_sensors_settings);
 	if (err < 0)
-		return err;
+		goto st_magn_power_off;
 
 	mdata->num_data_channels = ST_MAGN_NUMBER_DATA_CHANNELS;
 	mdata->multiread_bit = mdata->sensor_settings->multi_read_bit;
@@ -607,11 +609,11 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
 
 	err = st_sensors_init_sensor(indio_dev, NULL);
 	if (err < 0)
-		return err;
+		goto st_magn_power_off;
 
 	err = st_magn_allocate_ring(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_magn_power_off;
 
 	if (irq > 0) {
 		err = st_sensors_allocate_trigger(indio_dev,
@@ -634,6 +636,8 @@ int st_magn_common_probe(struct iio_dev *indio_dev)
 		st_sensors_deallocate_trigger(indio_dev);
 st_magn_probe_trigger_error:
 	st_magn_deallocate_ring(indio_dev);
+st_magn_power_off:
+	st_sensors_power_disable(indio_dev);
 
 	return err;
 }

drivers/iio/pressure/st_pressure_core.c

@@ -649,13 +649,15 @@ int st_press_common_probe(struct iio_dev *indio_dev)
 	indio_dev->info = &press_info;
 	mutex_init(&press_data->tb.buf_lock);
 
-	st_sensors_power_enable(indio_dev);
+	err = st_sensors_power_enable(indio_dev);
+	if (err)
+		return err;
 
 	err = st_sensors_check_device_support(indio_dev,
 					ARRAY_SIZE(st_press_sensors_settings),
 					st_press_sensors_settings);
 	if (err < 0)
-		return err;
+		goto st_press_power_off;
 
 	press_data->num_data_channels = ST_PRESS_NUMBER_DATA_CHANNELS;
 	press_data->multiread_bit = press_data->sensor_settings->multi_read_bit;
@@ -676,11 +678,11 @@ int st_press_common_probe(struct iio_dev *indio_dev)
 
 	err = st_sensors_init_sensor(indio_dev, press_data->dev->platform_data);
 	if (err < 0)
-		return err;
+		goto st_press_power_off;
 
 	err = st_press_allocate_ring(indio_dev);
 	if (err < 0)
-		return err;
+		goto st_press_power_off;
 
 	if (irq > 0) {
 		err = st_sensors_allocate_trigger(indio_dev,
@@ -703,6 +705,8 @@ int st_press_common_probe(struct iio_dev *indio_dev)
 		st_sensors_deallocate_trigger(indio_dev);
 st_press_probe_trigger_error:
 	st_press_deallocate_ring(indio_dev);
+st_press_power_off:
+	st_sensors_power_disable(indio_dev);
 
 	return err;
 }

include/linux/iio/common/st_sensors.h

@@ -280,7 +280,7 @@ 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);
+int st_sensors_power_enable(struct iio_dev *indio_dev);
 
 void st_sensors_power_disable(struct iio_dev *indio_dev);