linux-kernel - [PATCH v1 02/10] gpio: pca953x: Fully convert to device managed resources

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Message-Id: <20230901134041.1165562-2-andriy.shevchenko@linux.intel.com>
Date:   Fri,  1 Sep 2023 16:40:33 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        linux-gpio@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     Linus Walleij <linus.walleij@...aro.org>,
        Bartosz Golaszewski <brgl@...ev.pl>,
        Andy Shevchenko <andy@...nel.org>
Subject: [PATCH v1 02/10] gpio: pca953x: Fully convert to device managed resources

Curtrently the error path is unsynchronised with removal due to
regulator being disabled before other device managed resources
are handled. Correct that by wrapping regulator enablement in
the respective call.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 drivers/gpio/gpio-pca953x.c | 68 +++++++++++++++++++------------------
 1 file changed, 35 insertions(+), 33 deletions(-)

diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index 02695abd0eb1..0dedb2265744 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -1045,13 +1045,40 @@ static int device_pca957x_init(struct pca953x_chip *chip)
 	return ret;
 }
 
+static void pca953x_disable_regulator(void *reg)
+{
+	regulator_disable(reg);
+}
+
+static int pca953x_get_and_enable_regulator(struct pca953x_chip *chip)
+{
+	struct device *dev = &chip->client->dev;
+	struct regulator *reg = chip->regulator;
+	int ret;
+
+	reg = devm_regulator_get(dev, "vcc");
+	if (IS_ERR(reg))
+		return dev_err_probe(dev, PTR_ERR(reg), "reg get err\n");
+
+	ret = regulator_enable(reg);
+	if (ret)
+	        return dev_err_probe(dev, ret, "reg en err\n");
+
+	ret = devm_add_action_or_reset(dev, pca953x_disable_regulator, reg);
+	if (ret)
+		return ret;
+
+	chip->regulator = reg;
+	return 0;
+}
+
 static int pca953x_probe(struct i2c_client *client)
 {
+	struct device *dev = &client->dev;
 	struct pca953x_platform_data *pdata;
 	struct pca953x_chip *chip;
 	int irq_base;
 	int ret;
-	struct regulator *reg;
 	const struct regmap_config *regmap_config;
 
 	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
@@ -1086,16 +1113,9 @@ static int pca953x_probe(struct i2c_client *client)
 	if (!chip->driver_data)
 		return -ENODEV;
 
-	reg = devm_regulator_get(&client->dev, "vcc");
-	if (IS_ERR(reg))
-		return dev_err_probe(&client->dev, PTR_ERR(reg), "reg get err\n");
-
-	ret = regulator_enable(reg);
-	if (ret) {
-		dev_err(&client->dev, "reg en err: %d\n", ret);
+	ret = pca953x_get_and_enable_regulator(chip);
+	if (ret)
 		return ret;
-	}
-	chip->regulator = reg;
 
 	i2c_set_clientdata(client, chip);
 
@@ -1118,10 +1138,8 @@ static int pca953x_probe(struct i2c_client *client)
 	}
 
 	chip->regmap = devm_regmap_init_i2c(client, regmap_config);
-	if (IS_ERR(chip->regmap)) {
-		ret = PTR_ERR(chip->regmap);
-		goto err_exit;
-	}
+	if (IS_ERR(chip->regmap))
+		return PTR_ERR(chip->regmap);
 
 	regcache_mark_dirty(chip->regmap);
 
@@ -1156,28 +1174,13 @@ static int pca953x_probe(struct i2c_client *client)
 		ret = device_pca95xx_init(chip);
 	}
 	if (ret)
-		goto err_exit;
+		return ret;
 
 	ret = pca953x_irq_setup(chip, irq_base);
 	if (ret)
-		goto err_exit;
+		return ret;
 
-	ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
-	if (ret)
-		goto err_exit;
-
-	return 0;
-
-err_exit:
-	regulator_disable(chip->regulator);
-	return ret;
-}
-
-static void pca953x_remove(struct i2c_client *client)
-{
-	struct pca953x_chip *chip = i2c_get_clientdata(client);
-
-	regulator_disable(chip->regulator);
+	return devm_gpiochip_add_data(dev, &chip->gpio_chip, chip);
 }
 
 #ifdef CONFIG_PM_SLEEP
@@ -1345,7 +1348,6 @@ static struct i2c_driver pca953x_driver = {
 		.acpi_match_table = pca953x_acpi_ids,
 	},
 	.probe		= pca953x_probe,
-	.remove		= pca953x_remove,
 	.id_table	= pca953x_id,
 };
 
-- 
2.40.0.1.gaa8946217a0b