[PATCH 0/9] iio: adc: ad7173: add SPI offload support

[David Lechner <dlechner@baylibre.com>]

Here comes another series for adding SPI offload support to an ADC.

The primary target is AD411x, but since this uses the ad_sigma_delta
shared module, a lot of this series is focused on that.

To start with, we have some cleanups to the ad_sigma_delta code, so feel
free to pick these up as they are ready as they generally stand on their
own.

Then before adding proper SPI offload support, we make use of
spi_optimize_message() to reduce CPU usage of all users of this driver
during buffered reads.

Also there is a new dt-binding and driver for a special SPI offload
trigger FPGA IP core that is used in this particular setup.

Then finally actual SPI offload support is added to the ad_sigma_delta
module and the ad7173 driver.

This was tested using EVAL-AD4112ARDZ on a DE10-Nano.

---
David Lechner (9):
      iio: adc: ad_sigma_delta: sort includes
      iio: adc: ad_sigma_delta: use u8 instead of uint8_t
      iio: adc: ad_sigma_delta: use BITS_TO_BYTES() macro
      iio: adc: ad_sigma_delta: refactor setting read address
      iio: adc: ad_sigma_delta: use spi_optimize_message()
      dt-bindings: trigger-source: add ADI Util Sigma-Delta SPI
      spi: offload trigger: add ADI Util Sigma-Delta SPI driver
      iio: adc: ad_sigma_delta: add SPI offload support
      iio: adc: ad7173: add SPI offload support

 .../trigger-source/adi,util-sigma-delta-spi.yaml   |  49 ++++
 MAINTAINERS                                        |   7 +-
 drivers/iio/adc/ad7173.c                           |  13 +
 drivers/iio/adc/ad_sigma_delta.c                   | 281 +++++++++++++--------
 drivers/spi/Kconfig                                |   5 +
 drivers/spi/Makefile                               |   1 +
 .../spi/spi-offload-trigger-adi-util-sigma-delta.c |  59 +++++
 include/linux/iio/adc/ad_sigma_delta.h             |  27 +-
 8 files changed, 330 insertions(+), 112 deletions(-)
---
base-commit: d02f330b0c78bcf76643fbb7d3215a58b181f829
change-id: 20250620-iio-adc-ad7173-add-spi-offload-support-32a178b666a3

Best regards,
-- 
David Lechner <dlechner@baylibre.com>