Re: [PATCH v7 4/4] leds: aw2013: Add AW2027 support

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Low] leds: aw2013: duplicated per-LED imax update in
  aw2013_chip_init()
--

commit fe70881eccdb317dc7ce37e26b9965b979fe6113
Author: Paul Sajna <sajattack@postmarketos.org>

leds: aw2013: Add AW2027 support

This commit adds support for the Awinic AW2027 3-channel LED controller to the
aw2013 driver, introducing chip-specific definitions and handling for its
global and per-channel current limits.

> diff --git a/drivers/leds/leds-aw2013.c b/drivers/leds/leds-aw2013.c
> index 7fe7e9dae9031..f62f977e2bfef 100644
> --- a/drivers/leds/leds-aw2013.c
> +++ b/drivers/leds/leds-aw2013.c

[ ... ]

> @@ -60,16 +72,88 @@ struct aw2013_led {

[ ... ]

> +static int aw2027_set_local_imax(struct aw2013 *chip, struct aw2013_led *led, u32 imax)
> +{
> +	return regmap_update_bits(chip->regmap,
> +				 AW2013_LCFG(led->num),
> +				 AW2027_LOCAL_IMAX_MASK,
> +				 imax);
> +}
> +
>  static int aw2013_chip_init(struct aw2013 *chip)
>  {
>  	int ret;
> @@ -81,17 +165,47 @@ static int aw2013_chip_init(struct aw2013 *chip)
>  		return ret;
>  	}
>  
> -	for (int i = 0; i < chip->num_leds; i++) {
> -		ret = regmap_update_bits(chip->regmap,
> -					 AW2013_LCFG(chip->leds[i].num),
> -					 AW2013_LCFG_IMAX_MASK,
> -					 chip->leds[i].imax);
> +	if (chip->cdef->gcr2_imax) {
> +		/*
> +		 * AW2027 supports 4-step global imax, and also a 16-step control for limiting
> +		 * individual current per LED. This doesn't map to the single value the
> +		 * devicetree provides super well, so set global imax to maximum, and
> +		 * local imax to whatever gets us closest to the value in the devicetree.
> +		 */
> +		ret = aw2027_set_global_imax(chip);
>  		if (ret) {
>  			dev_err(&chip->client->dev,
> -				"Failed to set maximum current for led %d: %d\n",
> -				chip->leds[i].num, ret);
> +				"Failed to set maximum global current: %d\n",
> +				ret);
>  			return ret;
>  		}
> +		/*
> +		 * This still needs to be here despite also being in aw2013_probe_dt,
> +		 * for cases where chip is disabled and re-enabled.
> +		 */
> +		for (int i = 0; i < chip->num_leds; i++) {
> +			ret = aw2027_set_local_imax(chip, &chip->leds[i], chip->leds[i].imax);
> +			if (ret) {
> +				dev_err(&chip->client->dev,
> +					"Failed to set maximum current for led %d: %d\n",
> +					chip->leds[i].num, ret);
> +				return ret;
> +			}
> +		}
> +	} else {
> +		/* AW2013 only supports 4-step individual current per LED */
> +		for (int i = 0; i < chip->num_leds; i++) {
> +			ret = regmap_update_bits(chip->regmap,
> +						 AW2013_LCFG(chip->leds[i].num),
> +						 AW2013_IMAX_MASK,
> +						 chip->leds[i].imax);
> +			if (ret) {
> +				dev_err(&chip->client->dev,
> +					"Failed to set maximum current for led %d: %d\n",
> +					chip->leds[i].num, ret);
> +				return ret;
> +			}
> +		}
>  	}

[ ... ]

> @@ -303,14 +417,30 @@ static int aw2013_probe_dt(struct aw2013 *chip)
>  
>  		mutex_lock(&chip->mutex);
>  		chip->num_leds = ++i;
> -		if (chip->enabled) {
> +		/*
> +		 * needs to be here and in aw2013_chip_init because chip->num_leds increments
> +		 * just above here while we're parsing the devicetree, and chip->enabled
> +		 * ensures chip_init runs as little as possible.
> +		 * Requires this function to have regulators enabled.
> +		 */
> +		if (chip->cdef->gcr2_imax) {
> +			ret = aw2027_set_local_imax(chip, led, led->imax);
> +			if (ret) {
> +				mutex_unlock(&chip->mutex);
> +				return dev_err_probe(&chip->client->dev, ret,
> +						     "Failed to set maximum current for led %d\n",
> +						     led->num);
> +			}
> +		} else {
>  			ret = regmap_update_bits(chip->regmap,
>  						 AW2013_LCFG(led->num),
> -						 AW2013_LCFG_IMAX_MASK,
> +						 AW2013_IMAX_MASK,
>  						 led->imax);
>  			if (ret) {
>  				mutex_unlock(&chip->mutex);
> -				return ret;
> +				return dev_err_probe(&chip->client->dev, ret,
> +						     "Failed to set maximum current for led %d\n",
> +						     led->num);
>  			}
>  		}

[Severity: Low]
As reported by Lee Jones on v3 [1], why duplicate the per-LED current update
and error handling across the gcr2_imax branches in both aw2013_chip_init()
and aw2013_probe_dt()?

Both AW2027 and AW2013 update AW2013_LCFG(led->num) with led->imax via
regmap_update_bits() and differ only in the bitmask (AW2027_LOCAL_IMAX_MASK vs
AW2013_IMAX_MASK, i.e. chip->cdef->current_levels - 1), so a single common
loop in aw2013_chip_init() and a single update call in aw2013_probe_dt() can
handle both chips.

[1] https://lore.kernel.org/r/179198402838.839288.17911568760182808689@kernel.org

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261114-aw2013-aw20xx-rename-v7-0-ea5a3113a479@postmarketos.org?part=4