[PATCH 2/2] adc: stm32mp15: add support of generic channels binding

[Patrice CHOTARD]

On 11/23/22 16:20, Olivier Moysan wrote:
> Add support of generic IIO channels binding:
> ./devicetree/bindings/iio/adc/adc.yaml
> Keep support of st,adc-channels for backward compatibility.
> 
> Signed-off-by: Olivier Moysan <olivier.moysan at foss.st.com>
> ---
> 
>  drivers/adc/stm32-adc.c | 51 ++++++++++++++++++++++++++++++++++++-----
>  1 file changed, 45 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/adc/stm32-adc.c b/drivers/adc/stm32-adc.c
> index 1250385fbb92..85efc119dbf1 100644
> --- a/drivers/adc/stm32-adc.c
> +++ b/drivers/adc/stm32-adc.c
> @@ -200,24 +200,63 @@ static int stm32_adc_legacy_chan_init(struct udevice *dev, unsigned int num_chan
>  	return ret;
>  }
>  
> +static int stm32_adc_generic_chan_init(struct udevice *dev, unsigned int num_channels)
> +{
> +	struct adc_uclass_plat *uc_pdata = dev_get_uclass_plat(dev);
> +	struct stm32_adc *adc = dev_get_priv(dev);
> +	ofnode child;
> +	int val, ret;
> +
> +	ofnode_for_each_subnode(child, dev_ofnode(dev)) {
> +		ret = ofnode_read_u32(child, "reg", &val);
> +		if (ret) {
> +			dev_err(dev, "Missing channel index %d\n", ret);
> +			return ret;
> +		}
> +
> +		if (val >= adc->cfg->max_channels) {
> +			dev_err(dev, "Invalid channel %d\n", val);
> +			return -EINVAL;
> +		}
> +
> +		uc_pdata->channel_mask |= 1 << val;
> +	}
> +
> +	return 0;
> +}
> +
>  static int stm32_adc_chan_of_init(struct udevice *dev)
>  {
>  	struct adc_uclass_plat *uc_pdata = dev_get_uclass_plat(dev);
>  	struct stm32_adc *adc = dev_get_priv(dev);
>  	unsigned int num_channels;
>  	int ret;
> -
> -	ret = stm32_adc_get_legacy_chan_count(dev);
> -	if (ret < 0)
> -		return ret;
> -	num_channels = ret;
> +	bool legacy = false;
> +
> +	num_channels = dev_get_child_count(dev);
> +	/* If no channels have been found, fallback to channels legacy properties. */
> +	if (!num_channels) {
> +		legacy = true;
> +
> +		ret = stm32_adc_get_legacy_chan_count(dev);
> +		if (!ret) {
> +			dev_err(dev, "No channel found\n");
> +			return -ENODATA;
> +		} else if (ret < 0) {
> +			return ret;
> +		}
> +		num_channels = ret;
> +	}
>  
>  	if (num_channels > adc->cfg->max_channels) {
>  		dev_err(dev, "too many st,adc-channels: %d\n", num_channels);
>  		return -EINVAL;
>  	}
>  
> -	ret = stm32_adc_legacy_chan_init(dev, num_channels);
> +	if (legacy)
> +		ret = stm32_adc_legacy_chan_init(dev, num_channels);
> +	else
> +		ret = stm32_adc_generic_chan_init(dev, num_channels);
>  	if (ret < 0)
>  		return ret;
>  
Reviewed-by: Patrice Chotard <patrice.chotard at foss.st.com>

Thanks
Patrice