Re: [PATCH RFC v4 05/10] iio: frequency: ad9910: add digital ramp generator support

From: Jonathan Cameron

Date: Sun May 17 2026 - 11:03:19 EST


On Fri, 08 May 2026 18:00:21 +0100
Rodrigo Alencar via B4 Relay <devnull+rodrigo.alencar.analog.com@xxxxxxxxxx> wrote:

> From: Rodrigo Alencar <rodrigo.alencar@xxxxxxxxxx>
>
> Add Digital Ramp Generator channels with destination selection (frequency,
> phase, or amplitude) based on attribute writes, dwell mode control,
> configurable upper/lower limits, step size controlled with rate of change
> config, and step rate controlled as sampling frequency.
>
> Signed-off-by: Rodrigo Alencar <rodrigo.alencar@xxxxxxxxxx>
> ---
> drivers/iio/frequency/ad9910.c | 511 ++++++++++++++++++++++++++++++++++++++++-


> static const struct iio_chan_spec_ext_info ad9910_phy_ext_info[] = {
> AD9910_EXT_INFO("powerdown", AD9910_POWERDOWN, IIO_SEPARATE),
> { }
> @@ -677,6 +939,14 @@ static const struct iio_chan_spec_ext_info ad9910_pp_ext_info[] = {
> { }
> };
>
> +static const struct iio_chan_spec_ext_info ad9910_drg_ramp_ext_info[] = {
> + AD9910_EXT_INFO("dwell_en", AD9910_DRG_DWELL_EN, IIO_SEPARATE),
> + AD9910_DRG_EXT_INFO("frequency_roc", AD9910_DRG_FREQ_ROC),
> + AD9910_DRG_EXT_INFO("phase_roc", AD9910_DRG_PHASE_ROC),
> + AD9910_DRG_EXT_INFO("scale_roc", AD9910_DRG_AMP_ROC),

See abi docs reply. This scale made me wonder if we can make this just roc with it
scaled to be in the base units for altvoltage.

> + { }
> +};