Input: mpr121 - use devm_regulator_get_enable_read_voltage()

We can reduce boilerplate code by using
devm_regulator_get_enable_read_voltage().

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20241119-input-mpr121-regulator-get-enable-read-voltage-v3-1-1d8ee5c22f6c@baylibre.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Author: dlech

drivers/input/keyboard/mpr121_touchkey.c

@@ -82,42 +82,6 @@ static const struct mpr121_init_register init_reg_table[] = {
 	{ AUTO_CONFIG_CTRL_ADDR, 0x0b },
 };
 
-static void mpr121_vdd_supply_disable(void *data)
-{
-	struct regulator *vdd_supply = data;
-
-	regulator_disable(vdd_supply);
-}
-
-static struct regulator *mpr121_vdd_supply_init(struct device *dev)
-{
-	struct regulator *vdd_supply;
-	int err;
-
-	vdd_supply = devm_regulator_get(dev, "vdd");
-	if (IS_ERR(vdd_supply)) {
-		dev_err(dev, "failed to get vdd regulator: %ld\n",
-			PTR_ERR(vdd_supply));
-		return vdd_supply;
-	}
-
-	err = regulator_enable(vdd_supply);
-	if (err) {
-		dev_err(dev, "failed to enable vdd regulator: %d\n", err);
-		return ERR_PTR(err);
-	}
-
-	err = devm_add_action_or_reset(dev, mpr121_vdd_supply_disable,
-				       vdd_supply);
-	if (err) {
-		dev_err(dev, "failed to add disable regulator action: %d\n",
-			err);
-		return ERR_PTR(err);
-	}
-
-	return vdd_supply;
-}
-
 static void mpr_touchkey_report(struct input_dev *dev)
 {
 	struct mpr121_touchkey *mpr121 = input_get_drvdata(dev);
@@ -233,19 +197,16 @@ static int mpr121_phys_init(struct mpr121_touchkey *mpr121,
 static int mpr_touchkey_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
-	struct regulator *vdd_supply;
 	int vdd_uv;
 	struct mpr121_touchkey *mpr121;
 	struct input_dev *input_dev;
 	u32 poll_interval = 0;
 	int error;
 	int i;
 
-	vdd_supply = mpr121_vdd_supply_init(dev);
-	if (IS_ERR(vdd_supply))
-		return PTR_ERR(vdd_supply);
-
-	vdd_uv = regulator_get_voltage(vdd_supply);
+	vdd_uv = devm_regulator_get_enable_read_voltage(dev, "vdd");
+	if (vdd_uv < 0)
+		return dev_err_probe(dev, vdd_uv, "failed to get vdd voltage\n");
 
 	mpr121 = devm_kzalloc(dev, sizeof(*mpr121), GFP_KERNEL);
 	if (!mpr121)