Re: [PATCH RFC v4 07/10] iio: frequency: ad9910: add output shift keying support

[Jonathan Cameron <jic23@kernel.org>]

On Fri, 08 May 2026 18:00:23 +0100
Rodrigo Alencar via B4 Relay <devnull+rodrigo.alencar.analog.com@kernel.org> wrote:

> From: Rodrigo Alencar <rodrigo.alencar@analog.com>
> 
> Add OSK channel with amplitude envelope control capabilities:
> - OSK enable/disable via IIO_CHAN_INFO_ENABLE;
> - Amplitude ramp rate control via IIO_CHAN_INFO_SAMP_FREQ;
> - Amplitude scale readback via IIO_CHAN_INFO_SCALE (ASF register);
> - Automatic OSK step size configurable througth the scale_roc extended
>   attribute, which allows for selectable step sizes in nano-units:
> 	- 0: no step, means manual mode (NOT pin controlled)
> 	- 61035: 1/2^14 step, automatic mode (pin controlled)
> 	- 122070: 2/2^14 step, automatic mode (pin controlled)
> 	- 244141: 4/2^14 step, automatic mode (pin controlled)
> 	- 488281: 8/2^14 step, automatic mode (pin controlled)
> 	- 1000000000: 1.0 step, manual mode (pin controlled)
> 
> The ASF register is initialized with a default amplitude ramp rate during
> device setup to ensure valid readback.
> 
> Signed-off-by: Rodrigo Alencar <rodrigo.alencar@analog.com>


>  
> +#define AD9910_OSK_EXT_INFO(_name, _ident) \
> +	AD9910_EXT_INFO_TMPL(_name, _ident, IIO_SEPARATE, osk_attrs)
> +
>  static const struct iio_chan_spec_ext_info ad9910_phy_ext_info[] = {
>  	AD9910_EXT_INFO("powerdown", AD9910_POWERDOWN, IIO_SEPARATE),
>  	{ }
> @@ -1018,6 +1154,12 @@ static const struct iio_chan_spec_ext_info ad9910_drg_ramp_ext_info[] = {
>  	{ }
>  };
>  
> +static const struct iio_chan_spec_ext_info ad9910_osk_ext_info[] = {
> +	AD9910_OSK_EXT_INFO("scale_roc", AD9910_OSK_AUTO_ROC),
> +	AD9910_OSK_EXT_INFO("scale_roc_available", AD9910_OSK_AUTO_ROC_AVAIL),
same questions about whether we can transform these to voltages and hence
not scale (though arguably the main unit of an altvoltage channel is a scale
of a 1V peak amplitude sine wave but meh).

> +	{ }
> +};