Re: [PATCH 24/38] iio: pressure-core: st: Expand and rename LPS331AP'schannel descriptor

[Jonathan Cameron]

On 09/10/13 13:49, Lee Jones wrote:
> Due to the MACRO used, the task of reading, understanding and maintaining
> the LPS331AP's channel descriptor is substantially difficult. This patch
> is based on the view that it's better to have easy to read, maintainable
> code than to save a few lines here and there. For that reason we're
> expanding the array so initialisation is completed in full.
> 
> Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
Agreed that in this case it is clearer not to use a macro.  When you have lots
of repeats (e.g. an adc with 16 channels) they can make sense, but here as
you say a few extra lines of code make it much easier to follow.
My only slight addition here would be to drop the IIO_NO_MOD and modified=0 bits
on the basis those are both the obvious defaults (and happen to be equal to 0).
Perhaps worth leaving them in this case as it makes the patch more obviously correct.

Applied to the togreg branch of iio.git

Thanks,

Jonathan
> ---
>  drivers/iio/pressure/st_pressure_core.c | 45 +++++++++++++++++++++++++--------
>  1 file changed, 34 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/iio/pressure/st_pressure_core.c b/drivers/iio/pressure/st_pressure_core.c
> index 2ee4bcd..60c2ee4 100644
> --- a/drivers/iio/pressure/st_pressure_core.c
> +++ b/drivers/iio/pressure/st_pressure_core.c
> @@ -64,16 +64,39 @@
>  #define ST_PRESS_LPS331AP_OUT_XL_ADDR		0x28
>  #define ST_TEMP_LPS331AP_OUT_L_ADDR		0x2b
>  
> -static const struct iio_chan_spec st_press_channels[] = {
> -	ST_SENSORS_LSM_CHANNELS(IIO_PRESSURE,
> +static const struct iio_chan_spec st_press_lps331ap_channels[] = {
> +	{
> +		.type = IIO_PRESSURE,
> +		.channel2 = IIO_NO_MOD,
> +		.address = ST_PRESS_LPS331AP_OUT_XL_ADDR,
> +		.scan_index = ST_SENSORS_SCAN_X,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = 24,
> +			.storagebits = 24,
> +			.endianness = IIO_LE,
> +		},
> +		.info_mask_separate =
>  			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
> -			ST_SENSORS_SCAN_X, 0, IIO_NO_MOD, 'u', IIO_LE, 24, 24,
> -			ST_PRESS_LPS331AP_OUT_XL_ADDR),
> -	ST_SENSORS_LSM_CHANNELS(IIO_TEMP,
> -			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) |
> -						BIT(IIO_CHAN_INFO_OFFSET),
> -			-1, 0, IIO_NO_MOD, 's', IIO_LE, 16, 16,
> -			ST_TEMP_LPS331AP_OUT_L_ADDR),
> +		.modified = 0,
> +	},
> +	{
> +		.type = IIO_TEMP,
> +		.channel2 = IIO_NO_MOD,
> +		.address = ST_TEMP_LPS331AP_OUT_L_ADDR,
> +		.scan_index = -1,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = 16,
> +			.storagebits = 16,
> +			.endianness = IIO_LE,
> +		},
> +		.info_mask_separate =
> +			BIT(IIO_CHAN_INFO_RAW) |
> +			BIT(IIO_CHAN_INFO_SCALE) |
> +			BIT(IIO_CHAN_INFO_OFFSET),
> +		.modified = 0,
> +	},
>  	IIO_CHAN_SOFT_TIMESTAMP(1)
>  };
>  
> @@ -83,7 +106,7 @@ static const struct st_sensors st_press_sensors[] = {
>  		.sensors_supported = {
>  			[0] = LPS331AP_PRESS_DEV_NAME,
>  		},
> -		.ch = (struct iio_chan_spec *)st_press_channels,
> +		.ch = (struct iio_chan_spec *)st_press_lps331ap_channels,
>  		.odr = {
>  			.addr = ST_PRESS_LPS331AP_ODR_ADDR,
>  			.mask = ST_PRESS_LPS331AP_ODR_MASK,
> @@ -222,7 +245,7 @@ int st_press_common_probe(struct iio_dev *indio_dev,
>  	pdata->num_data_channels = ST_PRESS_NUMBER_DATA_CHANNELS;
>  	pdata->multiread_bit = pdata->sensor->multi_read_bit;
>  	indio_dev->channels = pdata->sensor->ch;
> -	indio_dev->num_channels = ARRAY_SIZE(st_press_channels);
> +	indio_dev->num_channels = ARRAY_SIZE(st_press_lps331ap_channels);
>  
>  	if (pdata->sensor->fs.addr != 0)
>  		pdata->current_fullscale = (struct st_sensor_fullscale_avl *)
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/