Re: [PATCH] leds: qcom-lpg: Check the return value of regmap_bulk_write()

[Lee Jones <lee@kernel.org>]

On Thu, 04 Dec 2025, Haotian Zhang wrote:

> The lpg_lut_store() function currently ignores the return value of
> regmap_bulk_write() and always returns 0. This can cause hardware write
> failures to go undetected, leading the caller to believe LUT programming
> succeeded when it may have failed.
> 
> Check the return value of regmap_bulk_write() in lpg_lut_store and return
> the error to the caller on failure.
> 
> Fixes: 24e2d05d1b68 ("leds: Add driver for Qualcomm LPG")
> Signed-off-by: Haotian Zhang <vulab@iscas.ac.cn>
> ---
>  drivers/leds/rgb/leds-qcom-lpg.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/leds/rgb/leds-qcom-lpg.c b/drivers/leds/rgb/leds-qcom-lpg.c
> index 4f2a178e3d26..76734b1520f6 100644
> --- a/drivers/leds/rgb/leds-qcom-lpg.c
> +++ b/drivers/leds/rgb/leds-qcom-lpg.c
> @@ -369,7 +369,7 @@ static int lpg_lut_store(struct lpg *lpg, struct led_pattern *pattern,
>  {
>  	unsigned int idx;
>  	u16 val;
> -	int i;
> +	int i, ret;
>  
>  	idx = bitmap_find_next_zero_area(lpg->lut_bitmap, lpg->lut_size,
>  					 0, len, 0);
> @@ -379,8 +379,10 @@ static int lpg_lut_store(struct lpg *lpg, struct led_pattern *pattern,
>  	for (i = 0; i < len; i++) {
>  		val = pattern[i].brightness;
>  
> -		regmap_bulk_write(lpg->map, lpg->lut_base + LPG_LUT_REG(idx + i),
> +		ret = regmap_bulk_write(lpg->map, lpg->lut_base + LPG_LUT_REG(idx + i),
>  				  &val, sizeof(val));

Fine, but you need to re-align this to the '(' above.

> +		if (ret)
> +			return ret;
>  	}
>  
>  	bitmap_set(lpg->lut_bitmap, idx, len);
> -- 
> 2.50.1.windows.1
> 

-- 
Lee Jones [李琼斯]