Re: [PATCH v2] iio: light: veml3328: reshape scale array for readability

On Thu, 30 Jul 2026 12:29:34 +0400
Giorgi Tchankvetadze <[email protected]> wrote:

> From: Giorgi Tchankvetadze <[email protected]>
> 
> The veml3328_scale_vals array is declared as a flattened [4][8] array,
> so accessing a scale value requires calculating the offset of its
> (val, val2) pair using gain_inx * 2.
> 
> Reshape the array as [4][4][2], with separate dimensions for integration
> time, gain and the scale value pair. This removes the manual stride
> calculation and makes the relationship between the indexes and values
> explicit.
> 
> Suggested-by: David Lechner <[email protected]>
> Signed-off-by: Giorgi Tchankvetadze <[email protected]>
> ---

Okay, this is better than my original implementation. No idea what I was
doing...

Reviewed-by: Joshua Crofts <[email protected]>

Thanks for improving my driver!

>  /* integration times in microseconds */
> @@ -184,9 +204,8 @@ static int veml3328_read_raw(struct iio_dev *indio_dev,
>  		if (it_inx >= ARRAY_SIZE(veml3328_it_times) || gain_inx >= 4)
>  			return -EINVAL;
>  
> -		/* Stride by 2 through the flattened array to match (val, val2) */
> -		*val = veml3328_scale_vals[it_inx][gain_inx * 2];
> -		*val2 = veml3328_scale_vals[it_inx][gain_inx * 2 + 1];
> +		*val = veml3328_scale_vals[it_inx][gain_inx][0];
> +		*val2 = veml3328_scale_vals[it_inx][gain_inx][1];
>  
>  		return IIO_VAL_INT_PLUS_MICRO;
>  
> @@ -282,8 +301,8 @@ static int veml3328_write_raw(struct iio_dev *indio_dev,
>  			return -EINVAL;
>  
>  		for (i = 0; i < 4; i++) {

Given how annoying hard-coded values are, could you change the `i < 4` to
`i < ARRAY_SIZE(veml3328_scale_vals[it_inx])`? This should also be done for 
the subsequent -EINVAL check as well. Feel free to do a separate patch.

> -			if (val == veml3328_scale_vals[it_inx][i * 2] &&
> -			    val2 == veml3328_scale_vals[it_inx][i * 2 + 1])
> +			if (val == veml3328_scale_vals[it_inx][i][0] &&
> +			    val2 == veml3328_scale_vals[it_inx][i][1])
>  				break;
>  		}
>  



-- 
Kind regards,
Joshua Crofts