This is a new driver for the Analog Devices AD7944/AD7985/AD7986 family of ADCs. These are fairly simple chips (e.g. no configuration registers). The initial driver is only supporting the 'multi' (4-wire) SPI mode. We plan to follow up with support for the 'single' (3-wire) SPI mode. This work is done on behalf of Analog Devices, Inc., hence the MAINTAINERS are @analog.com folks. --- Changes in v3: - Removed 'multi' value from adi,spi-mode property in DT bindings - Modified driver for above change - Fixed spelling of 'conventional' - Added '#daisy-chained-devices' to DT bindings - Added comments explaining that '3-wire' mode is not related to spi-3wire/SPI_3WIRE - Replaced _sign with _diff in chip info struct to properly handle pseudo-differential vs. true differential chips - Link to v2: https://lore.kernel.org/r/20240216-ad7944-mainline-v2-0-7eb69651e592@xxxxxxxxxxxx Changes in v2: - Added limit to spi-max-frequency for chain mode in DT bindings - Added spi-cpol property to DT bindings - Renamed '3-wire' mode to 'single' mode (to avoid confusion with spi-3wire) - Renamed '4-wire' mode to 'multi' mode - Dropped adi,reference property - now using only ref-supply and refin-supply to determine the reference voltage source - Fixed spelling of TURBO - Renamed t_cnv to t_conv to match datasheet name and fixed comment - Fixed wrong timestamp pushed to buffer - Fixed scaling for chips with signed data - Make use of sysfs_match_string() function - Link to v1: https://lore.kernel.org/r/20240206-ad7944-mainline-v1-0-bf115fa9474f@xxxxxxxxxxxx --- David Lechner (2): dt-bindings: iio: adc: add ad7944 ADCs iio: adc: ad7944: add driver for AD7944/AD7985/AD7986 .../devicetree/bindings/iio/adc/adi,ad7944.yaml | 213 +++++++++++ MAINTAINERS | 9 + drivers/iio/adc/Kconfig | 10 + drivers/iio/adc/Makefile | 1 + drivers/iio/adc/ad7944.c | 413 +++++++++++++++++++++ 5 files changed, 646 insertions(+) --- base-commit: 205bbf0d2dd2e0fcd6bf2a15b7df6fc570967e3b change-id: 20240206-ad7944-mainline-17c968aa0967
