Re: [PATCH v12 7/9] iio: adc: adi-axi-adc: add oversampling

[Jonathan Cameron <jic23@kernel.org>]

On Fri, 7 Feb 2025 16:09:16 +0200
Antoniu Miclaus <antoniu.miclaus@analog.com> wrote:

> Add support for enabling/disabling oversampling.
> 
> Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
> ---
> no changes in v12.
>  drivers/iio/adc/adi-axi-adc.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c
> index 272d82c6e887..872ff51e08a7 100644
> --- a/drivers/iio/adc/adi-axi-adc.c
> +++ b/drivers/iio/adc/adi-axi-adc.c
> @@ -46,6 +46,7 @@
>  #define    ADI_AXI_ADC_CTRL_DDR_EDGESEL_MASK	BIT(1)
>  
>  #define ADI_AXI_ADC_REG_CNTRL_3			0x004c
> +#define   AD485X_CNTRL_3_OS_EN_MSK		BIT(2)
>  #define   AD485X_CNTRL_3_PACKET_FORMAT_MSK	GENMASK(1, 0)
>  #define   AD485X_PACKET_FORMAT_20BIT		0x0
>  #define   AD485X_PACKET_FORMAT_24BIT		0x1
> @@ -363,6 +364,28 @@ static int axi_adc_data_size_set(struct iio_backend *back, unsigned int size)
>  				  FIELD_PREP(AD485X_CNTRL_3_PACKET_FORMAT_MSK, val));
>  }
>  
> +static int axi_adc_oversampling_ratio_set(struct iio_backend *back,

Same thing David pointed out in previous patch applies here.
axi_adc_ad4851_oversampling_ration_set() or something like that.


> +					  unsigned int ratio)
> +{
> +	struct adi_axi_adc_state *st = iio_backend_get_priv(back);
> +
> +	/* The current state of the function enables or disables the
> +	 * oversampling in REG_CNTRL_3 register. A ratio equal to 1 implies no
> +	 * oversampling, while a value greater than 1 implies oversampling being
> +	 * enabled.
> +	 */
> +	switch (ratio) {
> +	case 0:
> +		return -EINVAL;
> +	case 1:
> +		return regmap_clear_bits(st->regmap, ADI_AXI_ADC_REG_CNTRL_3,
> +					 AD485X_CNTRL_3_OS_EN_MSK);
> +	default:
> +		return regmap_set_bits(st->regmap, ADI_AXI_ADC_REG_CNTRL_3,
> +				       AD485X_CNTRL_3_OS_EN_MSK);
> +	}
> +}
> +
>  static struct iio_buffer *axi_adc_request_buffer(struct iio_backend *back,
>  						 struct iio_dev *indio_dev)
>  {
> @@ -428,6 +451,7 @@ static const struct iio_backend_ops adi_ad485x_ops = {
>  	.chan_status = axi_adc_chan_status,
>  	.interface_type_get = axi_adc_interface_type_get,
>  	.data_size_set = axi_adc_data_size_set,
> +	.oversampling_ratio_set = axi_adc_oversampling_ratio_set,
>  	.debugfs_reg_access = iio_backend_debugfs_ptr(axi_adc_reg_access),
>  	.debugfs_print_chan_status = iio_backend_debugfs_ptr(axi_adc_debugfs_print_chan_status),
>  };