RE: [PATCH v11 5/8] iio: adc: adi-axi-adc: set data format

[Miclaus, Antoniu]

> On 1/27/25 4:57 AM, Antoniu Miclaus wrote:
> > Add support for selecting the data format within the AXI ADC ip.
> >
> > Reviewed-by: Nuno Sa <nuno.sa@xxxxxxxxxx>
> > Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>
> > ---
> > no changes in v11.
> >  drivers/iio/adc/adi-axi-adc.c | 46
> +++++++++++++++++++++++++++++++++++
> >  1 file changed, 46 insertions(+)
> >
> > diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c
> > index d2e1dc63775c..3c213ca5ff8e 100644
> > --- a/drivers/iio/adc/adi-axi-adc.c
> > +++ b/drivers/iio/adc/adi-axi-adc.c
> > @@ -45,6 +45,12 @@
> >  #define ADI_AXI_ADC_REG_CTRL			0x0044
> >  #define    ADI_AXI_ADC_CTRL_DDR_EDGESEL_MASK	BIT(1)
> >
> > +#define ADI_AXI_ADC_REG_CNTRL_3			0x004c
> > +#define   AD485X_CNTRL_3_PACKET_FORMAT_MSK	GENMASK(1, 0)
> > +#define   AD485X_PACKET_FORMAT_20BIT		0x0
> > +#define   AD485X_PACKET_FORMAT_24BIT		0x1
> > +#define   AD485X_PACKET_FORMAT_32BIT		0x2
> > +
> >  #define ADI_AXI_ADC_REG_DRP_STATUS		0x0074
> >  #define   ADI_AXI_ADC_DRP_LOCKED		BIT(17)
> >
> > @@ -312,6 +318,45 @@ static int axi_adc_interface_type_get(struct
> iio_backend *back,
> >  	return 0;
> >  }
> >
> > +static int axi_adc_data_size_set(struct iio_backend *back, unsigned int size)
> > +{
> > +	struct adi_axi_adc_state *st = iio_backend_get_priv(back);
> > +	unsigned int val;
> > +
> > +	switch (size) {
> > +	/*
> > +	 * There are two different variants of the AXI AD485X IP block, a 16-bit
> > +	 * and a 20-bit variant.
> > +	 * The 0x0 value (AD485X_PACKET_FORMAT_20BIT) is corresponding
> also to
> > +	 * the 16-bit variant of the IP block.
> > +	 */
> > +	case 16:
> > +	case 20:
> > +		val = AD485X_PACKET_FORMAT_20BIT;
> > +		break;
> > +	case 24:
> > +		val = AD485X_PACKET_FORMAT_24BIT;
> > +		break;
> > +	/*
> > +	 * The 0x2 (AD485X_PACKET_FORMAT_32BIT) corresponds only to
> the 20-bit
> > +	 * variant of the IP block. Setting this value properly is ensured by
> > +	 * the upper layers of the drivers calling the axi-adc functions.
> > +	 * Also, for 16-bit IP block, the 0x2
> (AD485X_PACKET_FORMAT_32BIT)
> > +	 * value is handled as maximum size available which is 24-bit for this
> > +	 * configuration.
> > +	 */
> > +	case 32:
> > +		val = AD485X_PACKET_FORMAT_32BIT;
> > +		break;
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +
> > +	return regmap_update_bits(st->regmap,
> ADI_AXI_ADC_REG_CNTRL_3,
> > +				  AD485X_CNTRL_3_PACKET_FORMAT_MSK,
> > +
> FIELD_PREP(AD485X_CNTRL_3_PACKET_FORMAT_MSK, val));
> > +}
> > +
> >  static struct iio_buffer *axi_adc_request_buffer(struct iio_backend *back,
> >  						 struct iio_dev *indio_dev)
> >  {
> > @@ -360,6 +405,7 @@ static const struct iio_backend_ops adi_axi_adc_ops
> = {
> >  	.test_pattern_set = axi_adc_test_pattern_set,
> >  	.chan_status = axi_adc_chan_status,
> >  	.interface_type_get = axi_adc_interface_type_get,
> > +	.data_size_set = axi_adc_data_size_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),
> >  };
> 
> Why was [1] not addressed?
> 
> [1]: https://urldefense.com/v3/__https://lore.kernel.org/linux-
> iio/9c262f599fb9b42feac99cfb541723a0a6f50e6b.camel@xxxxxxxxx/__;!!A
> 3Ni8CS0y2Y!6uVytAwWUCsEazOUTACecMQkbMuHBF95sbla50CbTUFkZkyxS
> -S7jMOCczpoyKCjtAKvMOyrt0ukYwcXC_l5q60$

Indeed it was not addressed. I remained with the impression that adding part prefix
in the macro definitions was enough. I will add the compatible string support.
Although I have a question in order to minimize the number of versions to be sent
In the future. Should I add a separate patch for the compatible support (which
will not add value independently) or should I include it in this patch which adds
custom function for data format for the AD485x IP core?