Re: [PATCH] gpiolib: fix gpio-hog functionality

[Jules Maselbas <jmaselbas@kalray.eu>]

On Thu, Jun 01, 2023 at 04:32:09PM +0200, Sascha Hauer wrote:
> On Thu, Jun 01, 2023 at 04:25:06PM +0200, Marco Felsch wrote:
> > This reverts commit 3641d381e63321016e3bf09504852a6b2a2f879b.
> > 
> > Since the of_xlate support the gpio-hog support is broken because the
> > 'gpio' property used to specify the gpio-hog pin does not contain any
> > phandle. Due to the fact that of_xlate was never implemented the easiest
> > way to fix the gpio-hog functionality is to revert the commit.
> 
> 3641d381e63321016e3bf09504852a6b2a2f879b was introduced for sunxi. As
> Jules is currently working on sunxi support this is likely needed soon,
> so what's the second easiest way?
I am not very familiar with the gpio-hog concept, what I understand is:

"gpio-hog" are a description of gpios config to be initialized early on.
The main difference with classic gpio is the omission of the phandle of
the gpio controller (since gpio-hog are expected to be a child node of
gpio controller). Correct me if I am wrong.

In this case the current version of of_hog_gpio fails since it calls
of_parse_phandle_with_args which expect the gpio to start with the controller
phandle.

My best guess would be to rework of_hog_gpio to not use of_parse_phandle_with_args
and probably not gpio_of_xlate

This sounds easier than a sync of barebox gpio code with linux.

Cheers
-- Jules