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From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Mon, 28 Jun 2021 16:42:20 +0300
Message-ID: <CAHp75Vd6M6D9baiGi8fU8a=pfXnSKtEgQ4+eMiwPh6P9cg1ojA@mail.gmail.com>
Subject: Re: gpiochip_lock_as_irq on pins without FLAG_REQUESTED: bug or
 feature ?
To:     Vincent Pelletier <plr.vincent@gmail.com>
Cc:     Linus Walleij <linus.walleij@linaro.org>,
        Bartosz Golaszewski <bgolaszewski@baylibre.com>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Mon, Jun 28, 2021 at 4:40 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
> On Mon, Jun 28, 2021 at 6:37 AM Vincent Pelletier <plr.vincent@gmail.com> wrote:

> > While trying to debug an IRQ handling issue on a sifive-unmatched board
> > (which is a very recent board on a recent architecture, so I would not
> > be overly surprised if there were bugs in hiding), I realised that I was able
> > to claim via sysfs GPIO pins which are being actively used as IRQ sources.

And one important note: do NOT use sysfs GPIO interface. Use a GPIO
character device instead.

-- 
With Best Regards,
Andy Shevchenko