Re: [PATCH v2 1/2] iio: pressure: bmp280: Fix type for raw values

[Jonathan Cameron <jic23@kernel.org>]

On Sun, 29 Sep 2024 13:25:10 +0200
Vasileios Amoiridis <vassilisamir@gmail.com> wrote:

> The adc values coming directly from the sensor in the BM{E,P}{2,3}xx
> sensors are unsigned values so treat them as such.
> 
> Fixes: 80cd23f43ddc ("iio: pressure: bmp280: Add triggered buffer support")
Why is this a fix rather than a cleanup?  Looks to me like all the values
are going to be small enough that they fit either way.
So good to tidy up for consistency etc, but why a fixes tag?

I 

> Signed-off-by: Vasileios Amoiridis <vassilisamir@gmail.com>
> ---
>  drivers/iio/pressure/bmp280-core.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
> index 6c2606f34ec4..472a6696303b 100644
> --- a/drivers/iio/pressure/bmp280-core.c
> +++ b/drivers/iio/pressure/bmp280-core.c
> @@ -1023,7 +1023,8 @@ static irqreturn_t bmp280_trigger_handler(int irq, void *p)
>  	struct iio_poll_func *pf = p;
>  	struct iio_dev *indio_dev = pf->indio_dev;
>  	struct bmp280_data *data = iio_priv(indio_dev);
> -	s32 adc_temp, adc_press, t_fine;
> +	u32 adc_temp, adc_press;
These are filled as part of a get_unaligned_be24() so the value will never
be big enough that signed / unsigned should make any difference.

> +	s32 t_fine;
>  	int ret;
>  
>  	guard(mutex)(&data->lock);
> @@ -1137,7 +1138,8 @@ static irqreturn_t bme280_trigger_handler(int irq, void *p)
>  	struct iio_poll_func *pf = p;
>  	struct iio_dev *indio_dev = pf->indio_dev;
>  	struct bmp280_data *data = iio_priv(indio_dev);
> -	s32 adc_temp, adc_press, adc_humidity, t_fine;
> +	u32 adc_temp, adc_press, adc_humidity;
Same with these.
> +	s32 t_fine;
>  	int ret;
>  
>  	guard(mutex)(&data->lock);
> @@ -1616,7 +1618,8 @@ static irqreturn_t bmp380_trigger_handler(int irq, void *p)
>  	struct iio_poll_func *pf = p;
>  	struct iio_dev *indio_dev = pf->indio_dev;
>  	struct bmp280_data *data = iio_priv(indio_dev);
> -	s32 adc_temp, adc_press, t_fine;
These are similar but le24.

> +	u32 adc_temp, adc_press;
> +	s32 t_fine;
>  	int ret;
>  
>  	guard(mutex)(&data->lock);