diff mbox series

[v2,03/10] leds: aw2013: use devm API to cleanup module's resources

Message ID 20231204180603.470421-4-gnstark@salutedevices.com
State New
Headers
Series devm_led_classdev_register() usage problem |

Commit Message

George Stark Dec. 4, 2023, 6:05 p.m. UTC 
  In this driver LEDs are registered using devm_led_classdev_register()
so they are automatically unregistered after module's remove() is done.
led_classdev_unregister() calls module's led_set_brightness() to turn off
the LEDs and that callback uses resources which were destroyed already
in module's remove() so use devm API instead of remove().

Signed-off-by: George Stark <gnstark@salutedevices.com>
---
 drivers/leds/leds-aw2013.c | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

Comments

Andy Shevchenko Dec. 4, 2023, 6:15 p.m. UTC | #1 
On Mon, Dec 4, 2023 at 8:07 PM George Stark <gnstark@salutedevices.com> wrote:
>
> In this driver LEDs are registered using devm_led_classdev_register()
> so they are automatically unregistered after module's remove() is done.
> led_classdev_unregister() calls module's led_set_brightness() to turn off
> the LEDs and that callback uses resources which were destroyed already
> in module's remove() so use devm API instead of remove().

...

> +static void aw2013_chip_disable_action(void *data)
> +{
> +       struct aw2013 *chip = (struct aw2013 *)data;
> +
> +       aw2013_chip_disable(chip);
> +}

As with mutex release, this also can be oneliner

static void aw2013_chip_disable_action(void *chip)
{
       aw2013_chip_disable(chip);
}

...

> +       if (devm_mutex_init(&client->dev, &chip->mutex))
> +               return -ENOMEM;

Shouldn be

       ret = devm_mutex_init(&client->dev, &chip->mutex);
       if (ret)
           return ret;

?

> +               return -ENOMEM;
Christophe Leroy Dec. 4, 2023, 11:14 p.m. UTC | #2 
Le 04/12/2023 à 19:05, George Stark a écrit :
> In this driver LEDs are registered using devm_led_classdev_register()
> so they are automatically unregistered after module's remove() is done.
> led_classdev_unregister() calls module's led_set_brightness() to turn off
> the LEDs and that callback uses resources which were destroyed already
> in module's remove() so use devm API instead of remove().
> 
> Signed-off-by: George Stark <gnstark@salutedevices.com>
> ---
>   drivers/leds/leds-aw2013.c | 27 +++++++++++++++------------
>   1 file changed, 15 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/leds/leds-aw2013.c b/drivers/leds/leds-aw2013.c
> index c2bc0782c0cd..1a8acf303548 100644
> --- a/drivers/leds/leds-aw2013.c
> +++ b/drivers/leds/leds-aw2013.c
> @@ -1,6 +1,7 @@
>   // SPDX-License-Identifier: GPL-2.0+
>   // Driver for Awinic AW2013 3-channel LED driver
>   
> +#include <linux/devm-helpers.h>
>   #include <linux/i2c.h>
>   #include <linux/leds.h>
>   #include <linux/module.h>
> @@ -318,6 +319,13 @@ static int aw2013_probe_dt(struct aw2013 *chip)
>   	return 0;
>   }
>   
> +static void aw2013_chip_disable_action(void *data)
> +{
> +	struct aw2013 *chip = (struct aw2013 *)data;

The cast is not needed because data is void*

And chip is not needed at all, you can pass data to 
aw2013_chip_disable() directly, without a cast either.

> +
> +	aw2013_chip_disable(chip);
> +}
> +
>   static const struct regmap_config aw2013_regmap_config = {
>   	.reg_bits = 8,
>   	.val_bits = 8,
> @@ -334,7 +342,9 @@ static int aw2013_probe(struct i2c_client *client)
>   	if (!chip)
>   		return -ENOMEM;
>   
> -	mutex_init(&chip->mutex);
> +	if (devm_mutex_init(&client->dev, &chip->mutex))
> +		return -ENOMEM;

Why not return the value returned by devm_mutex_init() ?

> +
>   	mutex_lock(&chip->mutex);
>   
>   	chip->client = client;
> @@ -378,6 +388,10 @@ static int aw2013_probe(struct i2c_client *client)
>   		goto error_reg;
>   	}
>   
> +	ret = devm_add_action(&client->dev, aw2013_chip_disable_action, chip);
> +	if (ret)
> +		goto error_reg;
> +
>   	ret = aw2013_probe_dt(chip);
>   	if (ret < 0)
>   		goto error_reg;
> @@ -398,19 +412,9 @@ static int aw2013_probe(struct i2c_client *client)
>   
>   error:
>   	mutex_unlock(&chip->mutex);
> -	mutex_destroy(&chip->mutex);
>   	return ret;
>   }
>   
> -static void aw2013_remove(struct i2c_client *client)
> -{
> -	struct aw2013 *chip = i2c_get_clientdata(client);
> -
> -	aw2013_chip_disable(chip);
> -
> -	mutex_destroy(&chip->mutex);
> -}
> -
>   static const struct of_device_id aw2013_match_table[] = {
>   	{ .compatible = "awinic,aw2013", },
>   	{ /* sentinel */ },
> @@ -424,7 +428,6 @@ static struct i2c_driver aw2013_driver = {
>   		.of_match_table = of_match_ptr(aw2013_match_table),
>   	},
>   	.probe = aw2013_probe,
> -	.remove = aw2013_remove,
>   };
>   
>   module_i2c_driver(aw2013_driver);
diff mbox series

Patch

diff --git a/drivers/leds/leds-aw2013.c b/drivers/leds/leds-aw2013.c
index c2bc0782c0cd..1a8acf303548 100644
--- a/drivers/leds/leds-aw2013.c
+++ b/drivers/leds/leds-aw2013.c
@@ -1,6 +1,7 @@ 
 // SPDX-License-Identifier: GPL-2.0+
 // Driver for Awinic AW2013 3-channel LED driver
 
+#include <linux/devm-helpers.h>
 #include <linux/i2c.h>
 #include <linux/leds.h>
 #include <linux/module.h>
@@ -318,6 +319,13 @@  static int aw2013_probe_dt(struct aw2013 *chip)
 	return 0;
 }
 
+static void aw2013_chip_disable_action(void *data)
+{
+	struct aw2013 *chip = (struct aw2013 *)data;
+
+	aw2013_chip_disable(chip);
+}
+
 static const struct regmap_config aw2013_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
@@ -334,7 +342,9 @@  static int aw2013_probe(struct i2c_client *client)
 	if (!chip)
 		return -ENOMEM;
 
-	mutex_init(&chip->mutex);
+	if (devm_mutex_init(&client->dev, &chip->mutex))
+		return -ENOMEM;
+
 	mutex_lock(&chip->mutex);
 
 	chip->client = client;
@@ -378,6 +388,10 @@  static int aw2013_probe(struct i2c_client *client)
 		goto error_reg;
 	}
 
+	ret = devm_add_action(&client->dev, aw2013_chip_disable_action, chip);
+	if (ret)
+		goto error_reg;
+
 	ret = aw2013_probe_dt(chip);
 	if (ret < 0)
 		goto error_reg;
@@ -398,19 +412,9 @@  static int aw2013_probe(struct i2c_client *client)
 
 error:
 	mutex_unlock(&chip->mutex);
-	mutex_destroy(&chip->mutex);
 	return ret;
 }
 
-static void aw2013_remove(struct i2c_client *client)
-{
-	struct aw2013 *chip = i2c_get_clientdata(client);
-
-	aw2013_chip_disable(chip);
-
-	mutex_destroy(&chip->mutex);
-}
-
 static const struct of_device_id aw2013_match_table[] = {
 	{ .compatible = "awinic,aw2013", },
 	{ /* sentinel */ },
@@ -424,7 +428,6 @@  static struct i2c_driver aw2013_driver = {
 		.of_match_table = of_match_ptr(aw2013_match_table),
 	},
 	.probe = aw2013_probe,
-	.remove = aw2013_remove,
 };
 
 module_i2c_driver(aw2013_driver);