On 25.11.23 16:11, Jonathan Cameron wrote:
> On Sat, 25 Nov 2023 12:56:57 +0100
> Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx> wrote:
>
>> The Vishay VEMl6075 is a low power, 16-bit resolution UVA and UVB
>> light sensor with I2C interface and noise compensation (visible and
>> infrarred).
>>
>> Every UV channel generates an output signal measured in counts per
>> integration period, where the integration time is configurable.
>>
>> This driver adds support for both UV channels and the ultraviolet
>> index (UVI) inferred from them according to the device application note
>> with open-air (no teflon) coefficients.
>>
>> Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
>
> Hi Javier,
>
> A few more minor things. Looks good in general.
>
> Jonathan
>
>> +struct veml6075_data {
>> + struct i2c_client *client;
>> + struct regmap *regmap;
>> + struct mutex lock; /* integration time/measurement trigger lock */
>
> Could perhaps be clearer. Maybe something like
> /* Prevent integration time changing during a measurement */
>
It prevents integration time changing as well as measurement triggers
while a measurement is underway. I just wanted to cover both usages with
a short comment in the same line.
>> +
>> +static int veml6075_uva_comp(int raw_uva, int comp1, int comp2)
>> +{
>> + int comp1a_c, comp2a_c, uva_comp;
>> +
>> + comp1a_c = (comp1 * VEML6075_A_COEF) / 1000U;
>> + comp2a_c = (comp2 * VEML6075_B_COEF) / 1000U;
>> + uva_comp = raw_uva - comp1a_c - comp2a_c;
>> +
>> + return clamp_val(uva_comp, 0, U16_MAX);
>> +}
>> +
>> +static int veml6075_uvb_comp(int raw_uvb, int comp1, int comp2)
>> +{
>> + int comp1b_c, comp2b_c, uvb_comp;
>> +
>> + comp1b_c = (comp1 * VEML6075_C_COEF) / 1000U;
>
> Any of units.h appropriate here? I'm not sure if the / 1000U is a units
> thing or not.
>
These divisions are used to scale the coefficients down, as they are
defined as entire numbers. These coefficients have no units and the
resulting value is a count.
I have nothing to add to the rest of your comments. I will start working
on v3.
Thanks again for your thorough review.
Best regards,
Javier Carrasco
