[PATCH v4 0/2] Add support of the FXL6408 GPIO expander

[Oleksandr Suvorov]

Add support of the Fairchild's FXL6408 i2c gpio expander and enable
this driver for Toradex Colibri iMX8QXP SoM.

Changes in v4:
- fix misuse of MF_ID_x instead of FW_REV_x in fxl6408_probe().
- fix kernel doc formatting.
- sort headers.
- fix hex numbers style.
- explicitly claim values of enum io_direction.
- simplify fxl6408_get_function().
- make variable naming better in fxl6408_probe().

Changes in v3:
- fix a warning:
    "drivers/gpio/gpio-fxl6408.c:348:15: warning: format
    ‘%ld’ expects argument of type ‘long int’, but argument
    3 has type ‘int’ [-Wformat=]"
- add Tested-by record.

Changes in v2:
- Kconfig: add better description for the config option.
- gpio-fxl6408.c:
-- improve registers' naming.
-- fix code style (comments, etc.).
-- reimplement fxl6408_read() reducing number of parameters.
-- change return value of fxl6408_is_output() to bool.
-- replace IS_ERR_VALUE() macros with simple x < 0 where it's
   possible.
-- fxl6408_set_direction(): fix type of parameter "dir".
-- fix return error codes to avoid using the predefined in the driver
   model ones.
-- removed extra debug code.
-- expand TODO list.

Oleksandr Suvorov (2):
  GPIO: fxl6408: Add support for FXL6408 GPIO expander
  colibri-imx8x: add on-module gpio expander fxl6408

 arch/arm/dts/fsl-imx8qxp-colibri.dts |  27 ++
 configs/colibri-imx8x_defconfig      |   1 +
 drivers/gpio/Kconfig                 |   7 +
 drivers/gpio/Makefile                |   1 +
 drivers/gpio/gpio-fxl6408.c          | 380 +++++++++++++++++++++++++++
 5 files changed, 416 insertions(+)
 create mode 100644 drivers/gpio/gpio-fxl6408.c

-- 
2.33.1