linux-kernel - [PATCH v4 1/4] Input: atmel_mxt_ts - add power off and power on functions

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Date: Wed, 17 Apr 2024 11:05:24 +0200
From: Stefan Eichenberger <eichest@...il.com>
To: nick@...anahar.org,
	dmitry.torokhov@...il.com,
	robh@...nel.org,
	krzysztof.kozlowski+dt@...aro.org,
	conor+dt@...nel.org,
	nicolas.ferre@...rochip.com,
	alexandre.belloni@...tlin.com,
	claudiu.beznea@...on.dev,
	linus.walleij@...aro.org
Cc: linux-input@...r.kernel.org,
	devicetree@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	Stefan Eichenberger <stefan.eichenberger@...adex.com>
Subject: [PATCH v4 1/4] Input: atmel_mxt_ts - add power off and power on functions

From: Stefan Eichenberger <stefan.eichenberger@...adex.com>

Add a separate function for power off and power on instead of calling
regulator_bulk_enable and regulator_bulk_disable directly.

Signed-off-by: Stefan Eichenberger <stefan.eichenberger@...adex.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 59 +++++++++++++++---------
 1 file changed, 37 insertions(+), 22 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 542a31448c8f..52867ce3b9b6 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -1307,6 +1307,38 @@ static int mxt_soft_reset(struct mxt_data *data)
 	return 0;
 }
 
+static int mxt_power_on(struct mxt_data *data)
+{
+	int error;
+
+	error = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
+				      data->regulators);
+	if (error) {
+		dev_err(&data->client->dev, "failed to enable regulators: %d\n",
+			error);
+		return error;
+	}
+
+	msleep(MXT_BACKUP_TIME);
+
+	if (data->reset_gpio) {
+		/* Wait a while and then de-assert the RESET GPIO line */
+		msleep(MXT_RESET_GPIO_TIME);
+		gpiod_set_value(data->reset_gpio, 0);
+		msleep(MXT_RESET_INVALID_CHG);
+	}
+
+	return 0;
+}
+
+static void mxt_power_off(struct mxt_data *data)
+{
+	if (data->reset_gpio)
+		gpiod_set_value(data->reset_gpio, 1);
+
+	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
+}
+
 static void mxt_update_crc(struct mxt_data *data, u8 cmd, u8 value)
 {
 	/*
@@ -3305,25 +3337,9 @@ static int mxt_probe(struct i2c_client *client)
 		return error;
 	}
 
-	error = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
-				      data->regulators);
-	if (error) {
-		dev_err(&client->dev, "failed to enable regulators: %d\n",
-			error);
+	error = mxt_power_on(data);
+	if (error)
 		return error;
-	}
-	/*
-	 * The device takes 40ms to come up after power-on according
-	 * to the mXT224 datasheet, page 13.
-	 */
-	msleep(MXT_BACKUP_TIME);
-
-	if (data->reset_gpio) {
-		/* Wait a while and then de-assert the RESET GPIO line */
-		msleep(MXT_RESET_GPIO_TIME);
-		gpiod_set_value(data->reset_gpio, 0);
-		msleep(MXT_RESET_INVALID_CHG);
-	}
 
 	/*
 	 * Controllers like mXT1386 have a dedicated WAKE line that could be
@@ -3361,8 +3377,8 @@ static int mxt_probe(struct i2c_client *client)
 	mxt_free_input_device(data);
 	mxt_free_object_table(data);
 err_disable_regulators:
-	regulator_bulk_disable(ARRAY_SIZE(data->regulators),
-			       data->regulators);
+	mxt_power_off(data);
+
 	return error;
 }
 
@@ -3374,8 +3390,7 @@ static void mxt_remove(struct i2c_client *client)
 	sysfs_remove_group(&client->dev.kobj, &mxt_attr_group);
 	mxt_free_input_device(data);
 	mxt_free_object_table(data);
-	regulator_bulk_disable(ARRAY_SIZE(data->regulators),
-			       data->regulators);
+	mxt_power_off(data);
 }
 
 static int mxt_suspend(struct device *dev)
-- 
2.40.1