Re: Requesting false output GPIO as IRQ

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Tue, Feb 26, 2019 at 11:01 AM Geert Uytterhoeven
<geert@xxxxxxxxxxxxxx> wrote:

> While I strongly agree the firmware should be fixed not to configure
> random GPIOs as outputs, shouldn't Linux just override this, if the GPIO
> is not marked in use (has not been requested)?

commit 7e7c059cb50c7c72d5a393b2c34fc57de1b01b55
Author: Linus Walleij <linus.walleij@xxxxxxxxxx>
Date:   Wed Jun 22 16:31:54 2016 +0200

    gpio: convince line to become input in irq helper

    The generic IRQ helper library just checks if the IRQ line is
    set as input before activating it for interrupts. As we
    recently started to check things better with .get_dir() it
    turns out that it's good to try to convince the line to become
    an input before attempting to lock it as IRQ.

    Reviewed-by: Björn Andersson <bjorn.andersson@xxxxxxxxxx>
    Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

led to:

commit 78456d6ff815894e593675fc524cade9844501d5
Author: Linus Walleij <linus.walleij@xxxxxxxxxx>
Date:   Wed Jul 6 14:40:08 2016 +0200

    Revert "gpio: convince line to become input in irq helper"

    This reverts commit 7e7c059cb50c7c72d5a393b2c34fc57de1b01b55.

    I was wrong about trying to do this, as it breaks the
    orthogonality between gpiochips and irqchips.

    Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Mainly because of Grygorii's remarks:
https://marc.info/?l=linux-gpio&m=146779605005475&w=2

Yours,
Linus Walleij