Re: [PATCH 18/21] leds: aw2013: Unlock chip mutex before registering LEDs

[Nikita Travkin]

Lee Jones писал(а) 21.10.2026 17:32:
> aw2013_probe() holds chip->mutex across aw2013_probe_dt(), which calls
> devm_led_classdev_register_ext().  When a default trigger such as
> "timer" is configured on an LED in the Device Tree, the LED core
> synchronously activates the trigger during registration and invokes
> aw2013_blink_set() on the same thread, which attempts to acquire
> chip->mutex and deadlocks.
> 
> Reset the chip, disable the regulators, and release chip->mutex in
> aw2013_probe() before calling aw2013_probe_dt(), and update
> chip->num_leds before each LED is registered so trigger callbacks can
> enable the chip cleanly during registration.
> 
> Fixes: 59ea3c9faf32 ("leds: add aw2013 driver")
> Closes: https://sashiko.dev/#/bug/linux-5e2c9083-b95b-4aa4-aa0a-b0be8865ff12
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Lee Jones <lee@xxxxxxxxxx>

Reviewed-by: Nikita Travkin <nikita@xxxxxxx>

Thanks for making those fixes!
Nikita

> ---
>  drivers/leds/leds-aw2013.c | 54 ++++++++++++++++++++++----------------
>  1 file changed, 32 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/leds/leds-aw2013.c b/drivers/leds/leds-aw2013.c
> index dfeac8b2993f..c947cd068963 100644
> --- a/drivers/leds/leds-aw2013.c
> +++ b/drivers/leds/leds-aw2013.c
> @@ -271,8 +271,6 @@ static int aw2013_probe_dt(struct aw2013 *chip)
>  	if (!count || count > AW2013_MAX_LEDS)
>  		return -EINVAL;
>  
> -	regmap_write(chip->regmap, AW2013_RSTR, AW2013_RSTR_RESET);
> -
>  	for_each_available_child_of_node_scoped(np, child) {
>  		struct led_init_data init_data = {};
>  		u32 source;
> @@ -305,19 +303,29 @@ static int aw2013_probe_dt(struct aw2013 *chip)
>  		led->cdev.brightness_set_blocking = aw2013_brightness_set;
>  		led->cdev.blink_set = aw2013_blink_set;
>  
> +		mutex_lock(&chip->mutex);
> +		chip->num_leds = ++i;
> +		if (chip->enabled) {
> +			ret = regmap_update_bits(chip->regmap,
> +						 AW2013_LCFG(led->num),
> +						 AW2013_LCFG_IMAX_MASK,
> +						 led->imax);
> +			if (ret) {
> +				mutex_unlock(&chip->mutex);
> +				return ret;
> +			}
> +		}
> +		mutex_unlock(&chip->mutex);
> +
>  		ret = devm_led_classdev_register_ext(&chip->client->dev,
>  						     &led->cdev, &init_data);
>  		if (ret < 0)
>  			return ret;
> -
> -		i++;
>  	}
>  
>  	if (!count)
>  		return -EINVAL;
>  
> -	chip->num_leds = i;
> -
>  	return 0;
>  }
>  
> @@ -393,25 +401,27 @@ static int aw2013_probe(struct i2c_client *client)
>  		goto error_reg;
>  	}
>  
> +	ret = regmap_write(chip->regmap, AW2013_RSTR, AW2013_RSTR_RESET);
> +	if (ret) {
> +		dev_err(&client->dev, "Failed to reset chip: %d\n", ret);
> +		goto error_reg;
> +	}
> +
> +	ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
> +				     chip->regulators);
> +	if (ret) {
> +		dev_err(&client->dev,
> +			"Failed to disable regulators: %d\n", ret);
> +		goto error;
> +	}
> +
> +	mutex_unlock(&chip->mutex);
> +
>  	ret = devm_add_action(&client->dev, aw2013_chip_disable_action, chip);
>  	if (ret)
> -		goto error_reg;
> +		return ret;
>  
> -	ret = aw2013_probe_dt(chip);
> -	if (ret < 0)
> -		goto error_reg;
> -
> -	ret = regulator_bulk_disable(ARRAY_SIZE(chip->regulators),
> -				     chip->regulators);
> -	if (ret) {
> -		dev_err(&client->dev,
> -			"Failed to disable regulators: %d\n", ret);
> -		goto error;
> -	}
> -
> -	mutex_unlock(&chip->mutex);
> -
> -	return 0;
> +	return aw2013_probe_dt(chip);
>  
>  error_reg:
>  	regulator_bulk_disable(ARRAY_SIZE(chip->regulators),