Re: [PATCH v12 0/6] iio: adc: ad4691: add driver for AD4691 multichannel SAR ADC family

[Jonathan Cameron]

On Tue, 19 May 2026 15:20:21 +0300
Radu Sabau via B4 Relay <devnull+radu.sabau.analog.com@xxxxxxxxxx> wrote:

> This series adds support for the Analog Devices AD4691 family of
> high-speed, low-power multichannel successive approximation register
> (SAR) ADCs with an SPI-compatible serial interface.
> 
> The family includes:
>   - AD4691: 16-channel, 500 kSPS
>   - AD4692: 16-channel, 1 MSPS
>   - AD4693: 8-channel, 500 kSPS
>   - AD4694: 8-channel, 1 MSPS
> 
> The devices support two operating modes, auto-detected from the device
> tree:
>   - CNV Burst Mode: external PWM drives CNV independently of SPI;
>                     DATA_READY on a GP pin signals end of conversion
>   - Manual Mode: CNV tied to SPI CS; each SPI transfer reads
>                  the previous conversion result and starts the
>                  next (pipelined N+1 scheme)
> 
> A new driver is warranted rather than extending ad4695: the AD4691
> data path uses an accumulator-register model — results are read from
> AVG_IN registers, with ACC_MASK, ADC_SETUP, DEVICE_SETUP, and
> GPIO_MODE registers controlling the sequencer — none of which exist
> in AD4695. CNV Burst Mode (PWM drives CNV independently of SPI) and
> Manual Mode (pipelined N+1 transfers) also have no equivalent in
> AD4695's command-embedded single-cycle protocol.
> 
> The series is structured as follows:
>   1/6 - DT bindings (YAML schema) and MAINTAINERS entry
>   2/6 - Initial driver: register map via custom regmap callbacks,
>         IIO read_raw/write_raw, both operating modes, single-channel
>         reads via internal oscillator (Autonomous Mode)
>   3/6 - Triggered buffer support: IRQ-driven (DATA_READY on a GP pin
>         selected via interrupt-names) for CNV Burst Mode; external IIO
>         trigger for Manual Mode to handle the pipelined N+1 SPI protocol
>   4/6 - SPI Engine offload support: DMA-backed high-throughput
>         capture path using the SPI offload subsystem
>   5/6 - Per-channel oversampling ratio support for CNV Burst Mode
>   6/6 - Driver documentation (Documentation/iio/ad4691.rst)
> 
> Datasheets:
>   https://www.analog.com/en/products/ad4691.html
>   https://www.analog.com/en/products/ad4692.html
>   https://www.analog.com/en/products/ad4693.html
>   https://www.analog.com/en/products/ad4694.html
> 
> Signed-off-by: Radu Sabau <radu.sabau@xxxxxxxxxx>

I only plan to check the bit you've called out for v13. Series looks very
nice to me.  Hopefully I'll remember that and not reread the whole thing
again!  FWIW I'll be offline from end of today until Tuesday so it won't
get queued up until then at the earliest.

Jonathan