Re: [RFC 2/8] staging:iio:dac:ad5064: Use iio_enum for powerdown modes

[Jonathan Cameron <jic23@kernel.org>]

On 05/11/2012 04:53 PM, Lars-Peter Clausen wrote:
> This allows us to remove some boilerplate code for comparing and formatting the
> enum strings.
> 
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
>  drivers/staging/iio/dac/ad5064.c |   65 ++++++++++++--------------------------
>  1 file changed, 21 insertions(+), 44 deletions(-)
> 
> diff --git a/drivers/staging/iio/dac/ad5064.c b/drivers/staging/iio/dac/ad5064.c
> index da0fa12..276af02 100644
> --- a/drivers/staging/iio/dac/ad5064.c
> +++ b/drivers/staging/iio/dac/ad5064.c
> @@ -135,57 +135,42 @@ static int ad5064_sync_powerdown_mode(struct ad5064_state *st,
>  	return ret;
>  }
>  
> -static const char ad5064_powerdown_modes[][15] = {
> -	[AD5064_LDAC_PWRDN_NONE]	= "",
> -	[AD5064_LDAC_PWRDN_1K]		= "1kohm_to_gnd",
> -	[AD5064_LDAC_PWRDN_100K]	= "100kohm_to_gnd",
> -	[AD5064_LDAC_PWRDN_3STATE]	= "three_state",
> +static const char * const ad5064_powerdown_modes[] = {
> +	"1kohm_to_gnd",
> +	"100kohm_to_gnd",
> +	"three_state",
>  };
>  
> -static ssize_t ad5064_read_powerdown_mode_available(struct iio_dev *indio_dev,
> -	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
> -{
> -	return sprintf(buf, "%s %s %s\n", ad5064_powerdown_modes[1],
> -		ad5064_powerdown_modes[2], ad5064_powerdown_modes[3]);
> -}
> -
> -static ssize_t ad5064_read_powerdown_mode(struct iio_dev *indio_dev,
> -	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
> +static int ad5064_get_powerdown_mode(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan)
>  {
>  	struct ad5064_state *st = iio_priv(indio_dev);
>  
> -	return sprintf(buf, "%s\n",
> -		ad5064_powerdown_modes[st->pwr_down_mode[chan->channel]]);
> +	return st->pwr_down_mode[chan->channel] - 1;
>  }
>  
> -static ssize_t ad5064_write_powerdown_mode(struct iio_dev *indio_dev,
> -	uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
> -	size_t len)
> +static int ad5064_set_powerdown_mode(struct iio_dev *indio_dev,
> +	const struct iio_chan_spec *chan, unsigned int mode)
>  {
>  	struct ad5064_state *st = iio_priv(indio_dev);
> -	unsigned int mode, i;
>  	int ret;
>  
> -	mode = 0;
> -
> -	for (i = 1; i < ARRAY_SIZE(ad5064_powerdown_modes); ++i) {
> -		if (sysfs_streq(buf, ad5064_powerdown_modes[i])) {
> -			mode = i;
> -			break;
> -		}
> -	}
> -	if (mode == 0)
> -		return  -EINVAL;
> -
>  	mutex_lock(&indio_dev->mlock);
> -	st->pwr_down_mode[chan->channel] = mode;
> +	st->pwr_down_mode[chan->channel] = mode + 1;
>  
>  	ret = ad5064_sync_powerdown_mode(st, chan->channel);
>  	mutex_unlock(&indio_dev->mlock);
>  
> -	return ret ? ret : len;
> +	return ret;
>  }
>  
> +static const struct iio_enum ad5064_powerdown_mode_enum = {
> +	.items = ad5064_powerdown_modes,
> +	.num_items = ARRAY_SIZE(ad5064_powerdown_modes),
> +	.get = ad5064_get_powerdown_mode,
> +	.set = ad5064_set_powerdown_mode,
> +};
> +
>  static ssize_t ad5064_read_dac_powerdown(struct iio_dev *indio_dev,
>  	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
>  {
> @@ -285,22 +270,14 @@ static const struct iio_info ad5064_info = {
>  	.driver_module = THIS_MODULE,
>  };
>  
> -static struct iio_chan_spec_ext_info ad5064_ext_info[] = {
> +static const struct iio_chan_spec_ext_info ad5064_ext_info[] = {
>  	{
>  		.name = "powerdown",
>  		.read = ad5064_read_dac_powerdown,
>  		.write = ad5064_write_dac_powerdown,
>  	},
> -	{
> -		.name = "powerdown_mode",
> -		.read = ad5064_read_powerdown_mode,
> -		.write = ad5064_write_powerdown_mode,
> -	},
> -	{
> -		.name = "powerdown_mode_available",
> -		.shared = true,
> -		.read = ad5064_read_powerdown_mode_available,
> -	},
> +	IIO_ENUM("powerdown_mode", false, &ad5064_powerdown_mode_enum),
> +	IIO_ENUM_AVAILABLE("powerdown_mode", &ad5064_powerdown_mode_enum),
>  	{ },
>  };
>