Re: [PATCH v2 2/6] iio: adc: ad4080: prepare driver for multi-part support

[Nuno Sá]

On Tue, 2025-09-30 at 10:32 +0000, Antoniu Miclaus wrote:
> Refactor the ad4080 driver to support multiple ADC variants with
> different resolution bits and LVDS CNV clock count maximums.
> 
> Changes:
> - Add lvds_cnv_clk_cnt_max field to chip_info structure
> - Create AD4080_CHANNEL_DEFINE macro for variable resolution/storage bits
> - Make LVDS CNV clock count configurable per chip variant
> - Use chip_info->product_id for chip identification comparison
> 
> This prepares the infrastructure for adding support for additional
> ADC parts with different specifications while maintaining backward
> compatibility with existing AD4080 functionality.
> 
> Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>
> ---

Reviewed-by: Nuno Sá <nuno.sa@xxxxxxxxxx>

> changes in v2:
>  - allign all the \ to the left in the channel definition.
>  drivers/iio/adc/ad4080.c | 42 ++++++++++++++++++++++------------------
>  1 file changed, 23 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/iio/adc/ad4080.c b/drivers/iio/adc/ad4080.c
> index b80560aebe2d..fa15b8f63b8a 100644
> --- a/drivers/iio/adc/ad4080.c
> +++ b/drivers/iio/adc/ad4080.c
> @@ -167,6 +167,7 @@ struct ad4080_chip_info {
>  	const unsigned int (*scale_table)[2];
>  	const struct iio_chan_spec *channels;
>  	unsigned int num_channels;
> +	unsigned int lvds_cnv_clk_cnt_max;
>  };
>  
>  struct ad4080_state {
> @@ -414,23 +415,25 @@ static struct iio_chan_spec_ext_info ad4080_ext_info[] =
> {
>  	{ }
>  };
>  
> -static const struct iio_chan_spec ad4080_channel = {
> -	.type = IIO_VOLTAGE,
> -	.indexed = 1,
> -	.channel = 0,
> -	.info_mask_separate = BIT(IIO_CHAN_INFO_SCALE),
> -	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
> -			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> -	.info_mask_shared_by_all_available =
> -			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
> -	.ext_info = ad4080_ext_info,
> -	.scan_index = 0,
> -	.scan_type = {
> -		.sign = 's',
> -		.realbits = 20,
> -		.storagebits = 32,
> -	},
> -};
> +#define AD4080_CHANNEL_DEFINE(bits, storage) {				\
> +	.type = IIO_VOLTAGE,						\
> +	.indexed = 1,							\
> +	.channel = 0,							\
> +	.info_mask_separate =
> BIT(IIO_CHAN_INFO_SCALE),			\
> +	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |	\
> +			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),		\
> +	.info_mask_shared_by_all_available =				\
> +			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),		\
> +	.ext_info = ad4080_ext_info,					\
> +	.scan_index = 0,						\
> +	.scan_type = {							\
> +		.sign = 's',						\
> +		.realbits = (bits),					\
> +		.storagebits = (storage),				\
> +	},								\
> +}
> +
> +static const struct iio_chan_spec ad4080_channel = AD4080_CHANNEL_DEFINE(20,
> 32);
>  
>  static const struct ad4080_chip_info ad4080_chip_info = {
>  	.name = "ad4080",
> @@ -439,6 +442,7 @@ static const struct ad4080_chip_info ad4080_chip_info = {
>  	.num_scales = ARRAY_SIZE(ad4080_scale_table),
>  	.num_channels = 1,
>  	.channels = &ad4080_channel,
> +	.lvds_cnv_clk_cnt_max = AD4080_LVDS_CNV_CLK_CNT_MAX,
>  };
>  
>  static int ad4080_setup(struct iio_dev *indio_dev)
> @@ -463,7 +467,7 @@ static int ad4080_setup(struct iio_dev *indio_dev)
>  		return ret;
>  
>  	id = get_unaligned_le16(&id);
> -	if (id != AD4080_CHIP_ID)
> +	if (id != st->info->product_id)
>  		dev_info(dev, "Unrecognized CHIP_ID 0x%X\n", id);
>  
>  	ret = regmap_set_bits(st->regmap, AD4080_REG_GPIO_CONFIG_A,
> @@ -489,7 +493,7 @@ static int ad4080_setup(struct iio_dev *indio_dev)
>  				 AD4080_REG_ADC_DATA_INTF_CONFIG_B,
>  				
> AD4080_ADC_DATA_INTF_CONFIG_B_LVDS_CNV_CLK_CNT_MSK,
>  				
> FIELD_PREP(AD4080_ADC_DATA_INTF_CONFIG_B_LVDS_CNV_CLK_CNT_MSK,
> -					    AD4080_LVDS_CNV_CLK_CNT_MAX));
> +					    st->info->lvds_cnv_clk_cnt_max));
>  	if (ret)
>  		return ret;
>