Re: [PATCH v1 1/1] gpiolib: Read "gpio-line-names" from a firmware node

On Sun, Mar 07, 2021 at 06:14:49PM +0200, Andy Shevchenko wrote:

On Sun, Mar 7, 2021 at 4:22 PM Bartosz Golaszewski
[off-list ref] wrote:

quoted

On Fri, Mar 5, 2021 at 1:02 PM Andy Shevchenko
[off-list ref] wrote:

quoted

On STM32MP1, the GPIO banks are subnodes of pin-controller@50002000,
see arch/arm/boot/dts/stm32mp151.dtsi. The driver for
pin-controller@50002000 is in drivers/pinctrl/stm32/pinctrl-stm32.c
and iterates over all of its DT subnodes when registering each GPIO
bank gpiochip. Each gpiochip has:

  - gpio_chip.parent = dev,
    where dev is the device node of the pin controller
  - gpio_chip.of_node = np,
    which is the OF node of the GPIO bank

Therefore, dev_fwnode(chip->parent) != of_fwnode_handle(chip.of_node),
i.e. pin-controller@50002000 != pin-controller@50002000/gpio@5000*000.

The original code behaved correctly, as it extracted the "gpio-line-names"
from of_fwnode_handle(chip.of_node) = pin-controller@50002000/gpio@5000*000.

To achieve the same behaviour, read property from the firmware node.

...

quoted

Did you run the OF unit tests on this? The check for the parent dev
was added after a bug was reported that was only triggered in unit
tests.

Parent is not used anymore. But I can run unittests next week (or if
you know that they are failing now, can you please show the failure?).

For the record:
[   40.587868] ### dt-test ### end of unittest - 190 passed, 0 failed

If you have tests failed, we need more information about what line fails, etc.

-- 
With Best Regards,
Andy Shevchenko