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From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Thu, 15 Jun 2023 16:55:52 +0300
Message-ID: <CAHp75VcgAhaSARXMnRzsDE3x57AjnwS6Ep25Mz7SnizUccG6BA@mail.gmail.com>
Subject: Re: [PATCH v2] gpiolib: Fix GPIO chip IRQ initialization restriction
To:     Michael Walle <michael@walle.cc>
Cc:     Jiawen Wu <jiawenwu@trustnetic.com>, linus.walleij@linaro.org,
        brgl@bgdev.pl, shreeya.patel@collabora.com,
        linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org
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On Thu, Jun 15, 2023 at 1:45=E2=80=AFPM Michael Walle <michael@walle.cc> wr=
ote:
> > BTW, I wonder if it has problems when unregistering gpio-regmap.
> > Call Trace of irq_domain_remove() always exits in my test:
> > https://lore.kernel.org/all/011c01d98d3d$99e6c6e0$cdb454a0$@trustnetic.=
com/
> >
> > Of course, it could be because there was something wrong with my
> > test code. But I want to be clear about this.
>
> Mh, you've said you don't use the devm_ variant of
> regmap_add_irq_chip(),
> correct? Do you call regmap_del_irq_chip() yourself?
>
> It seems that gpiolib is already removing the domain itself. Mh.
> I guess if the the domain is set via gpiochip_irqchip_add_domain()
> gpiolib must not call irq_domain_remove() because the domain resource
> is handled externally (i.e. gpiolib doesn't allocate the domain
> itself) in our case.
>
> Nice finding! Looks like it has been broken since the beginning
> when I've introduced the gpiochip_irqchip_add_domain(). Will you
> do another fixes patch for that? I'm not sure where to store
> that information though. Maybe a new bool "no_domain_free"
> in struct gpio_irq_chip?

While reading this I also thought about flag, but please use positive
notation, e.g. "irq_domain_is_ext".

--=20
With Best Regards,
Andy Shevchenko