Re: [PATCH] gpio: sysfs: use const APIs for legacy sysfs attributes

[Bartosz Golaszewski]

On Wed, 21 Oct 2026 14:28:56 +0200, "Thomas Weißschuh"
<thomas.weissschuh@xxxxxxxxxxxxx> said:
> On Wed, Oct 21, 2026 at 01:17:54PM +0200, Thomas Weißschuh wrote:
>> On Wed, Oct 21, 2026 at 12:47:25PM +0200, Bartosz Golaszewski wrote:
>> > Replace the deprecated non-const sysfs attribute APIs with modern const
>> > variants where applicable. This leaves out the attributes embedded in
>> > struct gpiod_data as this structure contains fields that are modified at
>> > run-time.
>>
>> Leaving the dynamically allocated attributes with non-const signatures will
>> make it harder to remove the non-const APIs later on.
>> Would it be possible to switch those to const signatures, too and cast away
>> the constness in the store handlers?
>> I see that this is a legacy interface anyways, which might be gone by the
>> time we want to remove the non-const APIs. But that applies to the
>> currently proposed changes, too.
>
> If I understand correctly, the dynamically allocated attributes are only
> necessary to retreive 'struct gpiod_data' in the attribute registered on the
> *parent*. Those registered on the gpio device itself can just use dev_get_drvdata().
> Instead of registering the 'direction' and 'value' attributes on the parent,
> you could use symlinks pointing to the child attributes instead.
> This would make the code a whole lot simpler.
>
> Currently it is not possible to create symlinks to sysfs attributes, but I have
> simple patch for that locally. Let me know if you are interested.
>

Sure, definitely. Is this something that will eventually make it upstream
though?

Bart