Re: [PATCH v2 2/7] iio: mcp4531: provide range of available raw values

[Jonathan Cameron]

On 22/10/16 23:43, Peter Rosin wrote:
> Signed-off-by: Peter Rosin <peda@xxxxxxxxxx>
Looks great to me.

Perhaps it's worth doing a cat *_available in the directory and pasting
the result here to show what the resulting ABI looks like.

Also new ABI so needs documenting! (you didn't think it would be
this easy did you? :)

J
> ---
>  drivers/iio/potentiometer/mcp4531.c | 104 +++++++++++++++++++++---------------
>  1 file changed, 62 insertions(+), 42 deletions(-)
> 
> diff --git a/drivers/iio/potentiometer/mcp4531.c b/drivers/iio/potentiometer/mcp4531.c
> index 13b6ae2fcf7b..0d1bcf89ae17 100644
> --- a/drivers/iio/potentiometer/mcp4531.c
> +++ b/drivers/iio/potentiometer/mcp4531.c
> @@ -38,7 +38,7 @@
>  
>  struct mcp4531_cfg {
>  	int wipers;
> -	int max_pos;
> +	int avail[3];
>  	int kohms;
>  };
>  
> @@ -78,38 +78,38 @@ enum mcp4531_type {
>  };
>  
>  static const struct mcp4531_cfg mcp4531_cfg[] = {
> -	[MCP453x_502] = { .wipers = 1, .max_pos = 128, .kohms =   5, },
> -	[MCP453x_103] = { .wipers = 1, .max_pos = 128, .kohms =  10, },
> -	[MCP453x_503] = { .wipers = 1, .max_pos = 128, .kohms =  50, },
> -	[MCP453x_104] = { .wipers = 1, .max_pos = 128, .kohms = 100, },
> -	[MCP454x_502] = { .wipers = 1, .max_pos = 128, .kohms =   5, },
> -	[MCP454x_103] = { .wipers = 1, .max_pos = 128, .kohms =  10, },
> -	[MCP454x_503] = { .wipers = 1, .max_pos = 128, .kohms =  50, },
> -	[MCP454x_104] = { .wipers = 1, .max_pos = 128, .kohms = 100, },
> -	[MCP455x_502] = { .wipers = 1, .max_pos = 256, .kohms =   5, },
> -	[MCP455x_103] = { .wipers = 1, .max_pos = 256, .kohms =  10, },
> -	[MCP455x_503] = { .wipers = 1, .max_pos = 256, .kohms =  50, },
> -	[MCP455x_104] = { .wipers = 1, .max_pos = 256, .kohms = 100, },
> -	[MCP456x_502] = { .wipers = 1, .max_pos = 256, .kohms =   5, },
> -	[MCP456x_103] = { .wipers = 1, .max_pos = 256, .kohms =  10, },
> -	[MCP456x_503] = { .wipers = 1, .max_pos = 256, .kohms =  50, },
> -	[MCP456x_104] = { .wipers = 1, .max_pos = 256, .kohms = 100, },
> -	[MCP463x_502] = { .wipers = 2, .max_pos = 128, .kohms =   5, },
> -	[MCP463x_103] = { .wipers = 2, .max_pos = 128, .kohms =  10, },
> -	[MCP463x_503] = { .wipers = 2, .max_pos = 128, .kohms =  50, },
> -	[MCP463x_104] = { .wipers = 2, .max_pos = 128, .kohms = 100, },
> -	[MCP464x_502] = { .wipers = 2, .max_pos = 128, .kohms =   5, },
> -	[MCP464x_103] = { .wipers = 2, .max_pos = 128, .kohms =  10, },
> -	[MCP464x_503] = { .wipers = 2, .max_pos = 128, .kohms =  50, },
> -	[MCP464x_104] = { .wipers = 2, .max_pos = 128, .kohms = 100, },
> -	[MCP465x_502] = { .wipers = 2, .max_pos = 256, .kohms =   5, },
> -	[MCP465x_103] = { .wipers = 2, .max_pos = 256, .kohms =  10, },
> -	[MCP465x_503] = { .wipers = 2, .max_pos = 256, .kohms =  50, },
> -	[MCP465x_104] = { .wipers = 2, .max_pos = 256, .kohms = 100, },
> -	[MCP466x_502] = { .wipers = 2, .max_pos = 256, .kohms =   5, },
> -	[MCP466x_103] = { .wipers = 2, .max_pos = 256, .kohms =  10, },
> -	[MCP466x_503] = { .wipers = 2, .max_pos = 256, .kohms =  50, },
> -	[MCP466x_104] = { .wipers = 2, .max_pos = 256, .kohms = 100, },
> +	[MCP453x_502] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =   5, },
> +	[MCP453x_103] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =  10, },
> +	[MCP453x_503] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =  50, },
> +	[MCP453x_104] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 100, },
> +	[MCP454x_502] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =   5, },
> +	[MCP454x_103] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =  10, },
> +	[MCP454x_503] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms =  50, },
> +	[MCP454x_104] = { .wipers = 1, .avail = { 0, 1, 128 }, .kohms = 100, },
> +	[MCP455x_502] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =   5, },
> +	[MCP455x_103] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =  10, },
> +	[MCP455x_503] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =  50, },
> +	[MCP455x_104] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 100, },
> +	[MCP456x_502] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =   5, },
> +	[MCP456x_103] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =  10, },
> +	[MCP456x_503] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms =  50, },
> +	[MCP456x_104] = { .wipers = 1, .avail = { 0, 1, 256 }, .kohms = 100, },
> +	[MCP463x_502] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =   5, },
> +	[MCP463x_103] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =  10, },
> +	[MCP463x_503] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =  50, },
> +	[MCP463x_104] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 100, },
> +	[MCP464x_502] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =   5, },
> +	[MCP464x_103] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =  10, },
> +	[MCP464x_503] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms =  50, },
> +	[MCP464x_104] = { .wipers = 2, .avail = { 0, 1, 128 }, .kohms = 100, },
> +	[MCP465x_502] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =   5, },
> +	[MCP465x_103] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =  10, },
> +	[MCP465x_503] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =  50, },
> +	[MCP465x_104] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 100, },
> +	[MCP466x_502] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =   5, },
> +	[MCP466x_103] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =  10, },
> +	[MCP466x_503] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms =  50, },
> +	[MCP466x_104] = { .wipers = 2, .avail = { 0, 1, 256 }, .kohms = 100, },
>  };
>  
>  #define MCP4531_WRITE (0 << 2)
> @@ -124,13 +124,14 @@ struct mcp4531_data {
>  	const struct mcp4531_cfg *cfg;
>  };
>  
> -#define MCP4531_CHANNEL(ch) {					\
> -	.type = IIO_RESISTANCE,					\
> -	.indexed = 1,						\
> -	.output = 1,						\
> -	.channel = (ch),					\
> -	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
> -	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
> +#define MCP4531_CHANNEL(ch) {						\
> +	.type = IIO_RESISTANCE,						\
> +	.indexed = 1,							\
> +	.output = 1,							\
> +	.channel = (ch),						\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
> +	.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_RAW),	\
>  }
>  
>  static const struct iio_chan_spec mcp4531_channels[] = {
> @@ -156,13 +157,31 @@ static int mcp4531_read_raw(struct iio_dev *indio_dev,
>  		return IIO_VAL_INT;
>  	case IIO_CHAN_INFO_SCALE:
>  		*val = 1000 * data->cfg->kohms;
> -		*val2 = data->cfg->max_pos;
> +		*val2 = data->cfg->avail[2];
>  		return IIO_VAL_FRACTIONAL;
>  	}
>  
>  	return -EINVAL;
>  }
>  
> +static int mcp4531_read_avail(struct iio_dev *indio_dev,
> +			      struct iio_chan_spec const *chan,
> +			      const int **vals, int *type, int *length,
> +			      long mask)
> +{
> +	struct mcp4531_data *data = iio_priv(indio_dev);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		*length = ARRAY_SIZE(data->cfg->avail);
> +		*vals = data->cfg->avail;
> +		*type = IIO_VAL_INT;
> +		return IIO_AVAIL_RANGE;
> +	}
> +
> +	return -EINVAL;
> +}
> +
>  static int mcp4531_write_raw(struct iio_dev *indio_dev,
>  			     struct iio_chan_spec const *chan,
>  			     int val, int val2, long mask)
> @@ -172,7 +191,7 @@ static int mcp4531_write_raw(struct iio_dev *indio_dev,
>  
>  	switch (mask) {
>  	case IIO_CHAN_INFO_RAW:
> -		if (val > data->cfg->max_pos || val < 0)
> +		if (val > data->cfg->avail[2] || val < 0)
>  			return -EINVAL;
>  		break;
>  	default:
> @@ -186,6 +205,7 @@ static int mcp4531_write_raw(struct iio_dev *indio_dev,
>  
>  static const struct iio_info mcp4531_info = {
>  	.read_raw = mcp4531_read_raw,
> +	.read_avail = mcp4531_read_avail,
>  	.write_raw = mcp4531_write_raw,
>  	.driver_module = THIS_MODULE,
>  };
>