Re: [PATCH v4 02/15] gpio: regmap: set gpio_chip of_node

From: Álvaro Fernández Rojas
Date: Thu Mar 04 2021 - 10:26:27 EST


Hi Andy,

> El 4 mar 2021, a las 16:17, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> escribió:
>
> On Thu, Mar 4, 2021 at 5:06 PM Álvaro Fernández Rojas <noltari@xxxxxxxxx> wrote:
>>> El 4 mar 2021, a las 11:35, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> escribió:
>>> On Thu, Mar 4, 2021 at 10:57 AM Álvaro Fernández Rojas
>>> <noltari@xxxxxxxxx> wrote:
>
>>>> + * @of_node: (Optional) The device node
>>>
>>>> + struct device_node *of_node;
>>>
>>> Can we use fwnode from day 1, please?
>>
>> Could you explain this? I haven’t dealt with fwnode never :$
>> BTW, this is done to fix this check when parsing gpio ranges:
>> https://github.com/torvalds/linux/blob/f69d02e37a85645aa90d18cacfff36dba370f797/drivers/gpio/gpiolib-of.c#L933-L934
>
> Use struct fwnode_handle pointer instead of OF-specific one.

But is that compatible with the current gpiolib-of code? :$

>
> Also here is the question, why do you need to have that field in the
> regmap config structure and can't simply use the parent's fwnode?
> Also I'm puzzled why it's not working w/o this patch: GPIO library
> effectively assigns parent's fwnode (okay, of_node right now).

Because gpio regmap a child node of the pin controller, which is the one probed (gpio regmap is probed from the pin controller).
Therefore the parent’s fwnode is useless, since the correct gpio_chip node is the child's one (we have pin-ranges declared in the child node, referencing the parent pinctrl node).

>
> --
> With Best Regards,
> Andy Shevchenko

Best regards,
Álvaro.