Re: [PATCH] gpio: ftgpio010: Fix platform_get_irq's error checking

[Linus Walleij]

Hi Arvind,

thanks for the patch!

On Thu, Nov 30, 2017 at 3:12 PM, Arvind Yadav <arvind.yadav.cs@xxxxxxxxx> wrote:

> The platform_get_irq() function returns negative if an error occurs.
> zero or positive number on success. platform_get_irq() error checking
> for zero is not correct.
>
> Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
(...)
>         irq = platform_get_irq(pdev, 0);
> -       if (!irq)
> -               return -EINVAL;
> +       if (irq < 0)
> +               return irq;

This is wrong.
For an in-depth explanation why irq 0 in not valid, see:
https://lwn.net/Articles/470820/

It should be:

if (irq <= 0)
  return irq ? irq : -EINVAL;

Please update and resubmit. If you have more patches like this,
correct them too.

Yours,
Linus Walleij