Re: [PATCH] gpio: cdev: don't report GPIOs requested as interrupts as used
From: Bartosz Golaszewski
Date: Fri Nov 01 2024 - 08:49:47 EST
On Fri, Nov 1, 2024 at 11:35 AM Linus Walleij <linus.walleij@xxxxxxxxxx> wrote:
>
> On Thu, Oct 31, 2024 at 9:08 PM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:
>
> > From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> >
> > GPIOs used as shared irqs can still be requested by user-space (or
> > kernel drivers for that matter) yet we report them as used over the
> > chardev ABI. Drop the test for FLAG_USED_AS_IRQ from
> > gpio_desc_to_lineinfo().
> >
> > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
>
> I think at the time this was added to not let userspace meddle with
> such GPIO lines since they were used for "something" in the kernel.
> (Userspace as second-class citizen.)
>
Well, it wouldn't prohibit it. It would just report it misleadingly.
Since we'll guard the fixed input direction, I think we should be
fine.
Bartosz
> But I guess this is fine:
> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
>
> Yours,
> Linus Walleij