On Wed, Jul 13, 2022 at 03:14:17PM +0200, Nuno Sá wrote:

The gpio core looks at 'FLAG_BIAS_DISABLE' in preparation of calling the
gpiochip 'set_config()' hook. However, AFAICT, there's no way that this
flag is set because there's no support for it in firwmare code. Moreover,
in 'gpiod_configure_flags()', only pull-ups and pull-downs are being
handled.

Isn't it enough?

On top of this, there are some users that are looking at
'PIN_CONFIG_BIAS_DISABLE' in the 'set_config()' hook. So, unless I'm
missing something, it looks like this was never working for these chips.

It seems you are looking into wrong source of issues. Isn't it a issue of
particular pin control driver?

Note that the ACPI case is only compiled tested. At first glance, it seems
the current patch is enough but i'm not really sure...

As a side note, this came to my attention during this patchset [1]
(and, ofr OF,  was tested with it).

-- 
With Best Regards,
Andy Shevchenko