Re: [PATCH 2/2] iio: light: add support for veml6031x00 ALS series

[Javier Carrasco <javier.carrasco.cruz@gmail.com>]

On 28/11/2024 10:55, kernel test robot wrote:
> Hi Javier,
> 
> kernel test robot noticed the following build warnings:
> 
> [auto build test WARNING on a61ff7eac77e86de828fe28c4e42b8ae9ec2b195]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Javier-Carrasco/dt-bindings-iio-light-veml6030-add-veml6031x00-ALS-series/20241128-104104
> base:   a61ff7eac77e86de828fe28c4e42b8ae9ec2b195
> patch link:    https://lore.kernel.org/r/20241126-veml6031x00-v1-2-4affa62bfefd%40gmail.com
> patch subject: [PATCH 2/2] iio: light: add support for veml6031x00 ALS series
> config: loongarch-allyesconfig (https://download.01.org/0day-ci/archive/20241128/202411281741.xz7mD4E2-lkp@intel.com/config)
> compiler: loongarch64-linux-gcc (GCC) 14.2.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241128/202411281741.xz7mD4E2-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202411281741.xz7mD4E2-lkp@intel.com/
> 
> All warnings (new ones prefixed by >>):
> 
>    drivers/iio/light/veml6031x00.c: In function 'veml6031x00_set_scale':
>>> drivers/iio/light/veml6031x00.c:422:24: warning: variable 'gain_idx' set but not used [-Wunused-but-set-variable]
>      422 |         int new_scale, gain_idx;
>          |                        ^~~~~~~~
> 
> 
> vim +/gain_idx +422 drivers/iio/light/veml6031x00.c
> 
>    418	
>    419	static int veml6031x00_set_scale(struct iio_dev *iio, int val, int val2)
>    420	{
>    421		struct veml6031x00_data *data = iio_priv(iio);
>  > 422		int new_scale, gain_idx;
>    423	
>    424		if (val == 0 && val2 == 125000) {
>    425			new_scale = FIELD_PREP(VEML6031X00_CONF1_GAIN, 0x03) |
>    426				VEML6031X00_CONF1_PD_D4;
>    427			gain_idx = 0;
>    428		} else if (val == 0 && val2 == 165000) {
>    429			new_scale = FIELD_PREP(VEML6031X00_CONF1_GAIN, 0x02) |
>    430				VEML6031X00_CONF1_PD_D4;
>    431			gain_idx = 1;
>    432		} else if (val == 0 && val2 == 250000) {
>    433			new_scale = FIELD_PREP(VEML6031X00_CONF1_GAIN, 0x00) |
>    434				VEML6031X00_CONF1_PD_D4;
>    435			gain_idx = 2;
>    436		} else if (val == 0 && val2 == 500000) {
>    437			new_scale = FIELD_PREP(VEML6031X00_CONF1_GAIN, 0x03);
>    438			gain_idx = 3;
>    439		} else if (val == 0 && val2 == 660000) {
>    440			new_scale = FIELD_PREP(VEML6031X00_CONF1_GAIN, 0x02);
>    441			gain_idx = 4;
>    442		} else if (val == 1 && val2 == 0) {
>    443			new_scale = FIELD_PREP(VEML6031X00_CONF1_GAIN, 0x00);
>    444			gain_idx = 5;
>    445		} else if (val == 2 && val2 == 0) {
>    446			new_scale = FIELD_PREP(VEML6031X00_CONF1_GAIN, 0x01);
>    447			gain_idx = 6;
>    448		} else {
>    449			return -EINVAL;
>    450		}
>    451	
>    452		return regmap_update_bits(data->regmap, VEML6031X00_REG_CONF1,
>    453					 VEML6031X00_CONF1_GAIN |
>    454					 VEML6031X00_CONF1_PD_D4,
>    455					 new_scale);
>    456	}
>    457	
> 

The gain_idx variable is a leftover of a previous approach where
processed values were also provided. But given that the conversion is
linear (raw * scale), processed values were dropped. I will also drop
this variable for v2 with the rest of the feedback I could get from this v1.

Best regards,
Javier Carrasco