Re: [PATCH RESEND 2/8] leds: syscon: Implement support for active-low property

[Lee Jones <lee@kernel.org>]

On Mon, 26 Dec 2022, Pali Rohár wrote:

> This new active-low property specify that LED has inverted logic
> (0 - enable LED, 1 - disable LED).
> 
> Signed-off-by: Pali Rohár <pali@kernel.org>
> Acked-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>  drivers/leds/leds-syscon.c | 14 ++++++++++----
>  1 file changed, 10 insertions(+), 4 deletions(-)

Reviewed-by: Lee Jones <lee@kernel.org>

> diff --git a/drivers/leds/leds-syscon.c b/drivers/leds/leds-syscon.c
> index 7eddb8ecb44e..5e605d8438e9 100644
> --- a/drivers/leds/leds-syscon.c
> +++ b/drivers/leds/leds-syscon.c
> @@ -29,6 +29,7 @@ struct syscon_led {
>  	struct regmap *map;
>  	u32 offset;
>  	u32 mask;
> +	bool active_low;
>  	bool state;
>  };
>  
> @@ -41,10 +42,10 @@ static void syscon_led_set(struct led_classdev *led_cdev,
>  	int ret;
>  
>  	if (value == LED_OFF) {
> -		val = 0;
> +		val = sled->active_low ? sled->mask : 0;
>  		sled->state = false;
>  	} else {
> -		val = sled->mask;
> +		val = sled->active_low ? 0 : sled->mask;
>  		sled->state = true;
>  	}
>  
> @@ -85,6 +86,8 @@ static int syscon_led_probe(struct platform_device *pdev)
>  		return -EINVAL;
>  	if (of_property_read_u32(np, "mask", &sled->mask))
>  		return -EINVAL;
> +	if (of_find_property(np, "active-low", NULL))
> +		sled->active_low = true;
>  
>  	state = of_get_property(np, "default-state", NULL);
>  	if (state) {
> @@ -95,17 +98,20 @@ static int syscon_led_probe(struct platform_device *pdev)
>  			if (ret < 0)
>  				return ret;
>  			sled->state = !!(val & sled->mask);
> +			if (sled->active_low)
> +				sled->state = !sled->state;
>  		} else if (!strcmp(state, "on")) {
>  			sled->state = true;
>  			ret = regmap_update_bits(map, sled->offset,
>  						 sled->mask,
> -						 sled->mask);
> +						 sled->active_low ? 0 : sled->mask);
>  			if (ret < 0)
>  				return ret;
>  		} else {
>  			sled->state = false;
>  			ret = regmap_update_bits(map, sled->offset,
> -						 sled->mask, 0);
> +						 sled->mask,
> +						 sled->active_low ? sled->mask : 0);
>  			if (ret < 0)
>  				return ret;
>  		}
> -- 
> 2.20.1
> 

-- 
Lee Jones [李琼斯]