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Date:   Mon, 14 Dec 2020 10:08:42 +1030
From:   "Andrew Jeffery" <andrew@aj.id.au>
To:     "Andy Shevchenko" <andy.shevchenko@gmail.com>,
        "Troy Lee" <troy_lee@aspeedtech.com>
Cc:     "OpenBMC Maillist" <openbmc@lists.ozlabs.org>,
        "Linus Walleij" <linus.walleij@linaro.org>,
        "Bartosz Golaszewski" <bgolaszewski@baylibre.com>,
        "Joel Stanley" <joel@jms.id.au>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        "moderated list:ARM/ASPEED MACHINE SUPPORT" 
        <linux-arm-kernel@lists.infradead.org>,
        "moderated list:ARM/ASPEED MACHINE SUPPORT" 
        <linux-aspeed@lists.ozlabs.org>,
        "open list" <linux-kernel@vger.kernel.org>,
        "Troy Lee" <leetroy@gmail.com>,
        "Ryan Chen" <ryan_chen@aspeedtech.com>,
        "Chia-Wei, Wang" <chiawei_wang@aspeedtech.com>
Subject: Re: [PATCH] gpio: aspeed: Lock GPIO pin used as IRQ
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On Fri, 11 Dec 2020, at 00:44, Andy Shevchenko wrote:
> On Thu, Dec 10, 2020 at 9:36 AM Troy Lee <troy_lee@aspeedtech.com> wrote:
> >
> > GPIO pins can be used as IRQ indicators. When they do,
> > those pins should be flaged with locks to avoid kernel
> 
> flagged
> 
> > warning message.
> 
> ...
> 
> > @@ -651,6 +651,13 @@ static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type)
> 
> > +       rc = gpiochip_lock_as_irq(&gpio->chip, d->hwirq);
> > +       if (rc) {
> > +               dev_err(gpio->chip.parent, "unable to lock GPIO %lu as IRQ\n",
> > +                       d->hwirq);
> > +               return rc;
> > +       }
> 
> It's a copy'n'paste of generic code. Why do you need it in an unusual
> place, i.e. ->irq_set_type() IIUC?
> Can you elaborate about an issue, because this seems to be a hack?

Yep - Troy please provide more information. What was the warning you saw? How
were the GPIOs allocated on the system that triggered the warning? What did you
do to trigger the warning?

Andrew