[PATCH v8 0/6] Maxim Integrated MAX77759 PMIC MFD-based drivers

["André Draszik" <andre.draszik@linaro.org>]

Hi,

This series improves support for the Maxim Integrated MAX77759
companion PMIC for USB Type-C applications using the MFD framework.

This series must be applied in-order, due to interdependencies of some
of the patches:
* to avoid use of undocumented compatibles by the newly added drivers,
  the bindings are added first in this series
* patch 1 ("dt-bindings: gpio: add max77759 binding") also creates a
  new MAINTAINERS entry, including a wildcard match for the other
  bindings in this series
* patch 3 ("dt-bindings: mfd: add max77759 binding") references the
  bindings added in patch 1 and 2 and can not work if those aren't
  available
* patch 4 ("mfd: max77759: add Maxim MAX77759 core mfd driver") adds
  the core MFD driver, which also exposes an API to its leaf drivers
  and is used by patches 5 and 6
* patches 5 and 6 won't compile without patch 4

The MAX77759 PMIC includes Battery Charger, Fuel Gauge, temperature
sensors, USB Type-C Port Controller (TCPC), NVMEM, and a GPIO expander.

This PMIC is used on the Google Pixel 6 and 6 Pro (oriole / raven).

This series adds support for the top-level MFD device, the gpio, and
nvmem cells. Other components are excluded for the following reasons:

    While in the same package, Fuel Gauge and TCPC have separate and
    independent I2C addresses, register maps, interrupt lines, and
    aren't part of the top-level package interrupt hierarchy.
    Furthermore, a driver for the TCPC part exists already (in
    drivers/usb/typec/tcpm/tcpci_maxim_core.c).

    I'm leaving out temperature sensors and charger in this submission,
    because the former are not in use on Pixel 6 and I therefore can
    not test them, and the latter can be added later, once we look at
    the whole charging topic in more detail.

To make maintainers' work easier, I am planning to send the relevant
DTS and defconfig changes via a different series, unless everything
is expected to go via Lee's MFD tree in one series?

Cheers,
Andre'

Signed-off-by: André Draszik <andre.draszik@linaro.org>
---
Changes in v8:
- gpio: switch to gpio_chip::set_rv() (Bartosz)
- gpio, nvmem: replace MODULE_ALIAS() with .id_table (Krzysztof)
- gpio, nvmem: drop previous tags due to above
- Link to v7: https://lore.kernel.org/r/20250428-max77759-mfd-v7-0-edfe40c16fe8@linaro.org

Changes in v7:
- rebased against next-20250424
- Link to v6: https://lore.kernel.org/r/20250325-max77759-mfd-v6-0-c0870ca662ba@linaro.org

Changes in v6:
- add one missing change in core driver
- Link to v5: https://lore.kernel.org/r/20250325-max77759-mfd-v5-0-69bd6f07a77b@linaro.org

Changes in v5:
- core: incorporate Lee's comments (hoping I didn't miss any :-)
- Link to v4: https://lore.kernel.org/r/20250312-max77759-mfd-v4-0-b908d606c8cb@linaro.org

Changes in v4:
- collect tags
- mfd: add missing build_bug.h include
- mfd: update an irq chip comment
- mfd: fix a whitespace in register definitions
- Link to v3: https://lore.kernel.org/r/20250228-max77759-mfd-v3-0-0c3627d42526@linaro.org

Changes in v3:
- collect tags
- mfd: drop gpio-controller and gpio-cells, GPIO is provided by the
  child (Rob)
- gpio: drop duplicate init of 'handled' variable in irq handler
- gpio: use boolean with IRQ_RETVAL() (Linus)
- gpio: drop 'virq' variable inside irq handler to avoid confusion
  (Linus)
- gpio: drop assignment of struct gpio_chip::owner (Linus)
- Link to v2: https://lore.kernel.org/r/20250226-max77759-mfd-v2-0-a65ebe2bc0a9@linaro.org

Changes in v2:
- reorder bindings patches to avoid validation failures
- add dependency information to cover letter (Krzysztof)
- fix max77759_gpio_direction_from_control() in gpio driver
- gpio: drop 'interrupts' property from binding and sort properties
  alphabetically (Rob)
- nvmem: drop example from nvmem binding as the MFD binding has a
  complete one (Rob)
- nvmem: rename expected nvmem subdev nodename to 'nvmem-0' (Rob)
- mfd: add kernel doc
- mfd: fix an msec / usec typo
- mfd: error handling of devm_mutex_init (Christophe)
- whitespace fixes & tidy-ups (Christophe)
- Link to v1: https://lore.kernel.org/r/20250224-max77759-mfd-v1-0-2bff36f9d055@linaro.org

---
André Draszik (6):
      dt-bindings: gpio: add max77759 binding
      dt-bindings: nvmem: add max77759 binding
      dt-bindings: mfd: add max77759 binding
      mfd: max77759: add Maxim MAX77759 core mfd driver
      gpio: max77759: add Maxim MAX77759 gpio driver
      nvmem: max77759: add Maxim MAX77759 NVMEM driver

 .../bindings/gpio/maxim,max77759-gpio.yaml         |  44 ++
 .../devicetree/bindings/mfd/maxim,max77759.yaml    |  99 +++
 .../bindings/nvmem/maxim,max77759-nvmem.yaml       |  32 +
 MAINTAINERS                                        |  10 +
 drivers/gpio/Kconfig                               |  13 +
 drivers/gpio/Makefile                              |   1 +
 drivers/gpio/gpio-max77759.c                       | 530 ++++++++++++++++
 drivers/mfd/Kconfig                                |  20 +
 drivers/mfd/Makefile                               |   1 +
 drivers/mfd/max77759.c                             | 690 +++++++++++++++++++++
 drivers/nvmem/Kconfig                              |  12 +
 drivers/nvmem/Makefile                             |   2 +
 drivers/nvmem/max77759-nvmem.c                     | 162 +++++
 include/linux/mfd/max77759.h                       | 165 +++++
 14 files changed, 1781 insertions(+)
---
base-commit: 33035b665157558254b3c21c3f049fd728e72368
change-id: 20250224-max77759-mfd-aaa7a3121b62

Best regards,
-- 
André Draszik <andre.draszik@linaro.org>