Re: [PATCH] iio: ltr501: Use a signed return type for ltr501_match_samp_freq

From: Peter Meerwald-Stadler
Date: Tue Jan 26 2016 - 07:10:46 EST



> The return type "unsigned int" was used by the ltr501_match_samp_freq function
> despite of the aspect that it will eventually return a negative error code.
> So, change to signed int and get the value by reference in the parameters.

ok, or just change the return type to int w/o adding a new pointer
argument?

> Done with the help of Coccinelle.
>
> Signed-off-by: Lucas Tanure <tanure@xxxxxxxxx>
> ---
> drivers/iio/light/ltr501.c | 27 +++++++++++++++------------
> 1 file changed, 15 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/iio/light/ltr501.c b/drivers/iio/light/ltr501.c
> index 809a961..99e8b12 100644
> --- a/drivers/iio/light/ltr501.c
> +++ b/drivers/iio/light/ltr501.c
> @@ -180,16 +180,19 @@ static const struct ltr501_samp_table ltr501_ps_samp_table[] = {
> {500000, 2000000}
> };
>
> -static unsigned int ltr501_match_samp_freq(const struct ltr501_samp_table *tab,
> - int len, int val, int val2)
> +static int ltr501_match_samp_freq(const struct ltr501_samp_table *tab,
> + int len, int val, int val2,
> + int *ret)
> {
> int i, freq;
>
> freq = val * 1000000 + val2;
>
> for (i = 0; i < len; i++) {
> - if (tab[i].freq_val == freq)
> - return i;
> + if (tab[i].freq_val == freq) {
> + *ret = i;
> + return 0;
> + }
> }
>
> return -EINVAL;
> @@ -236,12 +239,12 @@ static int ltr501_als_write_samp_freq(struct ltr501_data *data,
> {
> int i, ret;
>
> - i = ltr501_match_samp_freq(ltr501_als_samp_table,
> + ret = ltr501_match_samp_freq(ltr501_als_samp_table,
> ARRAY_SIZE(ltr501_als_samp_table),
> - val, val2);
> + val, val2, &i);
>
> - if (i < 0)
> - return i;
> + if (ret < 0)
> + return ret;
>
> mutex_lock(&data->lock_als);
> ret = regmap_field_write(data->reg_als_rate, i);
> @@ -255,12 +258,12 @@ static int ltr501_ps_write_samp_freq(struct ltr501_data *data,
> {
> int i, ret;
>
> - i = ltr501_match_samp_freq(ltr501_ps_samp_table,
> + ret = ltr501_match_samp_freq(ltr501_ps_samp_table,
> ARRAY_SIZE(ltr501_ps_samp_table),
> - val, val2);
> + val, val2, &i);
>
> - if (i < 0)
> - return i;
> + if (ret < 0)
> + return ret;
>
> mutex_lock(&data->lock_ps);
> ret = regmap_field_write(data->reg_ps_rate, i);
>

--

Peter Meerwald-Stadler
+43-664-2444418 (mobile)