[PATCH 3/3] iio: adc: ti-ads1015: convert to fully managed resources

[Archit Anant]

Refactor the driver to use devm_ allocations and power
management, allowing for the complete removal of the
ads1015_remove()

Key changes:
- Use devm_add_action_or_reset() to ensure the ADC is safely powered
down upon driver removal.
- Move to devm_pm_runtime_set_active_enabled() to manage the runtime
PM lifecycle.
- Update the PM operations to use DEFINE_RUNTIME_DEV_PM_OPS and
pm_ptr() for modern compiler saftey.
- Convert iio_device_register() and mutex_init() to their devm_
variants.
- Remove the thus obsolete ads1015_remove() function.

Signed-off-by: Archit Anant <architanant5@xxxxxxxxx>
---
 drivers/iio/adc/ti-ads1015.c | 58 ++++++++++++++++--------------------
 1 file changed, 26 insertions(+), 32 deletions(-)

diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c
index 0232a4ca2d77..57e5fa593b31 100644
--- a/drivers/iio/adc/ti-ads1015.c
+++ b/drivers/iio/adc/ti-ads1015.c
@@ -930,6 +930,14 @@ static int ads1015_set_conv_mode(struct ads1015_data *data, int mode)
 				  mode << ADS1015_CFG_MOD_SHIFT);
 }
 
+static void ads1015_power_off(void *data)
+{
+	struct ads1015_data *st = data;
+
+	/* power down single shot mode */
+	ads1015_set_conv_mode(st, ADS1015_SINGLESHOT);
+}
+
 static int ads1015_probe(struct i2c_client *client)
 {
 	const struct ads1015_chip_data *chip;
@@ -950,7 +958,9 @@ static int ads1015_probe(struct i2c_client *client)
 	data = iio_priv(indio_dev);
 	i2c_set_clientdata(client, indio_dev);
 
-	mutex_init(&data->lock);
+	ret = devm_mutex_init(dev, &data->lock);
+	if (ret)
+		return ret;
 
 	indio_dev->name = ADS1015_DRV_NAME;
 	indio_dev->modes = INDIO_DIRECT_MODE;
@@ -1033,38 +1043,23 @@ static int ads1015_probe(struct i2c_client *client)
 
 	data->conv_invalid = true;
 
-	ret = pm_runtime_set_active(dev);
+	ret = devm_add_action_or_reset(dev, ads1015_power_off, data);
 	if (ret)
 		return ret;
-	pm_runtime_set_autosuspend_delay(dev, ADS1015_SLEEP_DELAY_MS);
-	pm_runtime_use_autosuspend(dev);
-	pm_runtime_enable(dev);
 
-	ret = iio_device_register(indio_dev);
-	if (ret < 0) {
-		dev_err(dev, "Failed to register IIO device\n");
+	ret = devm_pm_runtime_set_active_enabled(dev);
+	if (ret)
 		return ret;
-	}
 
-	return 0;
-}
-
-static void ads1015_remove(struct i2c_client *client)
-{
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
-	struct ads1015_data *data = iio_priv(indio_dev);
-	int ret;
-
-	iio_device_unregister(indio_dev);
-
-	pm_runtime_disable(&client->dev);
-	pm_runtime_set_suspended(&client->dev);
+	pm_runtime_set_autosuspend_delay(dev, ADS1015_SLEEP_DELAY_MS);
+	pm_runtime_use_autosuspend(dev);
 
-	/* power down single shot mode */
-	ret = ads1015_set_conv_mode(data, ADS1015_SINGLESHOT);
+	ret = devm_iio_device_register(dev, indio_dev);
 	if (ret)
-		dev_warn(&client->dev, "Failed to power down (%pe)\n",
-			 ERR_PTR(ret));
+		return dev_err_probe(dev, ret,
+				     "Failed to register IIO device\n");
+
+	return 0;
 }
 
 #ifdef CONFIG_PM
@@ -1090,10 +1085,10 @@ static int ads1015_runtime_resume(struct device *dev)
 }
 #endif
 
-static const struct dev_pm_ops ads1015_pm_ops = {
-	SET_RUNTIME_PM_OPS(ads1015_runtime_suspend,
-			   ads1015_runtime_resume, NULL)
-};
+static DEFINE_RUNTIME_DEV_PM_OPS(ads1015_pm_ops,
+				  ads1015_runtime_suspend,
+				  ads1015_runtime_resume,
+				  NULL);
 
 static const struct ads1015_chip_data ads1015_data = {
 	.channels	= ads1015_channels,
@@ -1148,10 +1143,9 @@ static struct i2c_driver ads1015_driver = {
 	.driver = {
 		.name = ADS1015_DRV_NAME,
 		.of_match_table = ads1015_of_match,
-		.pm = &ads1015_pm_ops,
+		.pm = pm_ptr(&ads1015_pm_ops),
 	},
 	.probe		= ads1015_probe,
-	.remove		= ads1015_remove,
 	.id_table	= ads1015_id,
 };
 
-- 
2.39.5