[PATCH v5 0/3] iio: adc: add new ad7625 driver

[Trevor Gamblin]

This series adds a new driver for the Analog Devices Inc. AD7625,
AD7626, AD7960, and AD7961. These chips are part of a family of
LVDS-based SAR ADCs. The initial driver implementation does not support
the devices' self-clocked mode, although that can be added later.

The devices make use of two offset PWM signals, one to trigger
conversions and the other as a burst signal for transferring data to the
host. These rely on the new PWM waveform functionality being
reviewed in [1] and also available at [2].

This work is being done by BayLibre and on behalf of Analog Devices
Inc., hence the maintainers are @analog.com.

Special thanks to David Lechner for his guidance and reviews.

[1]: https://lore.kernel.org/linux-pwm/cover.1722261050.git.u.kleine-koenig@xxxxxxxxxxxx
[2]: https://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux.git/log/?h=pwm/chardev

Signed-off-by: Trevor Gamblin <tgamblin@xxxxxxxxxxxx>
---
Changes in v5:
- Link to v4: https://lore.kernel.org/r/20240904-ad7625_r1-v4-0-78bc7dfb2b35@xxxxxxxxxxxx

  [PATCH 1/3]
  - Picked up Reviewed-by tag from Conor, missed in v4

  [PATCH 2/3]
  - Make frequency values in ad7625_set_sampling_freq() u32 and make
    struct members match. Also do the same for 'target' variable
  - Use DIV_ROUND_CLOSEST() and DIV_ROUND_UP() instead of ULL variants
  - Change occurrences of sample_rate to sample_freq to be more
    consistent throughout driver
  - Picked up Nuno's Reviewed-by tag

  [PATCH 3/3]
  - No change

Changes in v4:
- Link to v3: https://lore.kernel.org/r/20240819-ad7625_r1-v3-0-75d5217c76b5@xxxxxxxxxxxx
- Rebase on top of latest pwm/chardev branch at:
  https://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux.git/log/?h=pwm/chardev

  [PATCH 1/3]
  - No change

  [PATCH 2/3]
  - Add 'depends on PWM' under 'CONFIG AD7625' in
    drivers/iio/adc/Kconfig, based on v3 discussions
  - Cleanup whitespace usage in Kconfig, bandwidth logic to match
    Jonathan's suggestions

  [PATCH 3/3]
  - No change

Changes in v3:
- Link to v2: https://lore.kernel.org/r/20240809-ad7625_r1-v2-0-f85e7ac83150@xxxxxxxxxxxx
  
  [PATCH 1/3]
  - Add gpio bindings header, en0-gpios and en1-gpios to binding example
  - Remove unnecessary comments

  [PATCH 2/3]
  - No change

  [PATCH 3/3]
  - No change

Changes in v2:
- Link to v1 (marked as RFC): https://lore.kernel.org/r/20240731-ad7625_r1-v1-0-a1efef5a2ab9@xxxxxxxxxxxx
- Include link to required PWM patch series in cover letter (missing before)
- Include new link to the pwm/chardev branch of Uwe's kernel tree
  
  [PATCH 1/3]
  - Rework dt bindings to be compliant using make dt_binding_check
  - Add "adi,no-dco" flag to address indication of how DCO lines are
    configured
  - Fix binding patch message
  - Remove chip packaging info from binding description
  - Move comments around to be clearer

  [PATCH 2/3]
  - Remove ad7625_pwm_disable(), call pwm_disable() directly
  - Add ad7625_buffer_preenable() and ad7625_buffer_postdisable()
    functions
  - Add devm_ad7625_regulator_setup() function, move all regulator logic
    to it, consolidate the comment blocks related to it above
  - Add have_refin flag in ad7625_state struct
  - Add pwm_waveform structs to ad7625_state struct for storing
    requested waveform characteristics
  - Refactor ad7625_set_sampling_freq() to set the pwm_waveform struct
    values in ad7625_state, limiting PWM enable/disable to
    preenable/postdisable functions
  - Remove redundant dev_err_probe() after devm_ad7625_pwm_get()
  - Use device_property_read_bool() instead of device_property_present()
  - General alignment and line wrapping fixes

  [PATCH 3/3]
  - No change

---
Trevor Gamblin (3):
      dt-bindings: iio: adc: add AD762x/AD796x ADCs
      iio: adc: ad7625: add driver
      docs: iio: new docs for ad7625 driver

 .../devicetree/bindings/iio/adc/adi,ad7625.yaml    | 176 ++++++
 Documentation/iio/ad7625.rst                       |  91 +++
 MAINTAINERS                                        |  11 +
 drivers/iio/adc/Kconfig                            |  16 +
 drivers/iio/adc/Makefile                           |   1 +
 drivers/iio/adc/ad7625.c                           | 684 +++++++++++++++++++++
 6 files changed, 979 insertions(+)
---
base-commit: 1ebd3850421749eb44bd040b249bd4db88d35b33
change-id: 20240730-ad7625_r1-60d17ea28958

Best regards,
-- 
Trevor Gamblin <tgamblin@xxxxxxxxxxxx>