Re: [PATCH] Revert "gpiolib: generalize devprop_gpiochip_set_names() for device properties"

[Marek Vasut <marex@denx.de>]

On 3/5/21 1:03 PM, Andy Shevchenko wrote:
> On Fri, Mar 05, 2021 at 11:51:02AM +0100, Marek Vasut wrote:
>> On 3/5/21 11:44 AM, Andy Shevchenko wrote:
>>> On Fri, Mar 05, 2021 at 12:09:56AM +0100, Marek Vasut wrote:
>>>> This reverts 7cba1a4d5e162 ("gpiolib: generalize devprop_gpiochip_set_names()
>>>> for device properties") because this breaks OF "gpio-line-names" behavior on
>>>> STM32MP1 platform.
>>>>
>>>> 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.
>>>> This patch reinstates the original correct behavior.
>>>
>>>> Signed-off-by: Marek Vasut <marex@denx.de>
>>>> Reported-by: Roman Guskov <rguskov@dh-electronics.com>
>>>
>>> Thanks for the report and a fix!
>>> However I think the revert is not an option. We may do much better.
>>
>> The revert is pretty much also the minimal change to reinstate the original
>> behavior. What better option do you have in mind, please do elaborate in
>> detail. Thank you.
> 
> Patch has been tested and just sent. Please test it on your side.

That one is even better and works too, thanks.