[PATCH] iio: adc: max9611: explicitly cast gain_selectors

[PATCH] iio: adc: max9611: explicitly cast gain_selectors

[Stefan Agner]

After finding a reasonable gain, the function converts the configured
gain to a gain configuration option selector enum max9611_csa_gain.
Make the conversion clearly visible by using an explicit cast. This
also avoids a warning seen with clang:
  drivers/iio/adc/max9611.c:292:16: warning: implicit conversion from
      enumeration type 'enum max9611_conf_ids' to different enumeration
      type 'enum max9611_csa_gain' [-Wenum-conversion]
                        *csa_gain = gain_selectors[i];
                                  ~ ^~~~~~~~~~~~~~~~~

Signed-off-by: Stefan Agner <stefan@agner.ch>
---
 drivers/iio/adc/max9611.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/adc/max9611.c b/drivers/iio/adc/max9611.c
index 0538ff8c4ac1..643a4e66eb80 100644
--- a/drivers/iio/adc/max9611.c
+++ b/drivers/iio/adc/max9611.c
@@ -289,7 +289,7 @@ static int max9611_read_csa_voltage(struct max9611_dev *max9611,
 			return ret;
 
 		if (*adc_raw > 0) {
-			*csa_gain = gain_selectors[i];
+			*csa_gain = (enum max9611_csa_gain)gain_selectors[i];
 			return 0;
 		}
 	}
-- 
2.18.0

Re: [PATCH] iio: adc: max9611: explicitly cast gain_selectors

[Jonathan Cameron]

On Sat, 11 Aug 2018 11:12:19 +0200
Stefan Agner <stefan@agner.ch> wrote:

> After finding a reasonable gain, the function converts the configured
> gain to a gain configuration option selector enum max9611_csa_gain.
> Make the conversion clearly visible by using an explicit cast. This
> also avoids a warning seen with clang:
>   drivers/iio/adc/max9611.c:292:16: warning: implicit conversion from
>       enumeration type 'enum max9611_conf_ids' to different enumeration
>       type 'enum max9611_csa_gain' [-Wenum-conversion]
>                         *csa_gain = gain_selectors[i];
>                                   ~ ^~~~~~~~~~~~~~~~~
> 
> Signed-off-by: Stefan Agner <stefan@agner.ch>
Hmm. This is a somewhat odd code construct, but it kind of makes sense
as it enforces that we are using a subset of one enum for the other.

Not terribly pretty but not awful I guess.

This patch is fine given that.

Applied to the togreg branch of iio.git and pushed out as testing for
the autobuilders to play with it.

Thanks,

Jonathan

> ---
>  drivers/iio/adc/max9611.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/adc/max9611.c b/drivers/iio/adc/max9611.c
> index 0538ff8c4ac1..643a4e66eb80 100644
> --- a/drivers/iio/adc/max9611.c
> +++ b/drivers/iio/adc/max9611.c
> @@ -289,7 +289,7 @@ static int max9611_read_csa_voltage(struct max9611_dev *max9611,
>  			return ret;
>  
>  		if (*adc_raw > 0) {
> -			*csa_gain = gain_selectors[i];
> +			*csa_gain = (enum max9611_csa_gain)gain_selectors[i];
>  			return 0;
>  		}
>  	}