Re: [PATCH v1 1/2] iio: adc: ti-adc128s052: add support for adc121s021

[Matti Vaittinen]

Hi Lothar,

On 25/06/2025 20:02, Lothar Rubusch wrote:
> Add support for the single channel variant(s) of this ADC.
>
> Signed-off-by: Lothar Rubusch <l.rubusch@xxxxxxxxx>

Thanks for this addition. In principle, this looks good to me but I am 
afraid there is another colliding series being worked on:

https://lore.kernel.org/all/20250614091504.575685-3-sbellary@xxxxxxxxxxxx/

Maybe you can align the effort with Sukrut?

What I specifically like (and think is the right thing to do) in 
Sukrut's series is replacing the 'adc122s021_channels' -array with 
individual structures. In my opinion the array is just unnecessary 
complexity and individual structures are simpler.

Other than that, this looks good to me.

Yours,
	-- Matti


> ---
>   drivers/iio/adc/ti-adc128s052.c | 17 ++++++++++++++++-
>   1 file changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/adc/ti-adc128s052.c b/drivers/iio/adc/ti-adc128s052.c
> index 1b46a8155803..cf271c39e663 100644
> --- a/drivers/iio/adc/ti-adc128s052.c
> +++ b/drivers/iio/adc/ti-adc128s052.c
> @@ -7,6 +7,7 @@
>    * https://www.ti.com/lit/ds/symlink/adc128s052.pdf
>    * https://www.ti.com/lit/ds/symlink/adc122s021.pdf
>    * https://www.ti.com/lit/ds/symlink/adc124s021.pdf
> + * https://www.ti.com/lit/ds/symlink/adc121s021.pdf
>    */
>   
>   #include <linux/cleanup.h>
> @@ -110,6 +111,10 @@ static const struct iio_chan_spec adc128s052_channels[] = {
>   	ADC128_VOLTAGE_CHANNEL(7),
>   };
>   
> +static const struct iio_chan_spec adc121s021_channels[] = {
> +	ADC128_VOLTAGE_CHANNEL(0),
> +};
> +
>   static const struct iio_chan_spec adc122s021_channels[] = {
>   	ADC128_VOLTAGE_CHANNEL(0),
>   	ADC128_VOLTAGE_CHANNEL(1),
> @@ -143,6 +148,10 @@ static const struct adc128_configuration adc128_config[] = {
>   		.refname = "vdd",
>   		.other_regulators = &bd79104_regulators,
>   		.num_other_regulators = 1,
> +	}, {
> +		.channels = adc121s021_channels,
> +		.num_channels = ARRAY_SIZE(adc121s021_channels),
> +		.refname = "vref",
>   	},
>   };

I'd love seeing this array split to individual structs.

>   
> @@ -207,7 +216,10 @@ static const struct of_device_id adc128_of_match[] = {
>   	{ .compatible = "ti,adc124s051", .data = &adc128_config[2] },
>   	{ .compatible = "ti,adc124s101", .data = &adc128_config[2] },
>   	{ .compatible = "rohm,bd79104", .data = &adc128_config[3] },
> -	{ }
> +	{ .compatible = "ti,adc121s021", .data = &adc128_config[4] },
> +	{ .compatible = "ti,adc121s051", .data = &adc128_config[4] },
> +	{ .compatible = "ti,adc121s101", .data = &adc128_config[4] },
> +	{ },
>   };
>   MODULE_DEVICE_TABLE(of, adc128_of_match);
>   
> @@ -220,6 +232,9 @@ static const struct spi_device_id adc128_id[] = {
>   	{ "adc124s051", (kernel_ulong_t)&adc128_config[2] },
>   	{ "adc124s101", (kernel_ulong_t)&adc128_config[2] },
>   	{ "bd79104", (kernel_ulong_t)&adc128_config[3] },
> +	{ "adc121s021", (kernel_ulong_t)&adc128_config[4] },
> +	{ "adc121s051", (kernel_ulong_t)&adc128_config[4] },
> +	{ "adc121s101", (kernel_ulong_t)&adc128_config[4] },
>   	{ }
>   };
>   MODULE_DEVICE_TABLE(spi, adc128_id);