Re: [PATCH] gpio: pl061: Warn when IRQ line has not been configured

[Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>]

wt., 3 mar 2020 o 10:29 Alexander A Sverdlin
<alexander.sverdlin@xxxxxxxxx> napisał(a):
>
> From: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
>
> Existing (irq < 0) condition is always false because adev->irq has unsigned
> type and contains 0 in case of failed irq_of_parse_and_map(). Up to now all
> the mapping errors were silently ignored.
>
> Seems that repairing this check would be backwards-incompatible and might
> break the probe() for the implementations without IRQ support. Therefore
> warn the user instead.
>
> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
> ---
>  drivers/gpio/gpio-pl061.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpio/gpio-pl061.c b/drivers/gpio/gpio-pl061.c
> index 5df7782..3439120 100644
> --- a/drivers/gpio/gpio-pl061.c
> +++ b/drivers/gpio/gpio-pl061.c
> @@ -326,10 +326,8 @@ static int pl061_probe(struct amba_device *adev, const struct amba_id *id)
>
>         writeb(0, pl061->base + GPIOIE); /* disable irqs */
>         irq = adev->irq[0];
> -       if (irq < 0) {
> -               dev_err(&adev->dev, "invalid IRQ\n");
> -               return -ENODEV;
> -       }
> +       if (!irq)
> +               dev_warn(&adev->dev, "IRQ support disabled\n");
>         pl061->parent_irq = irq;
>
>         girq = &pl061->gc.irq;
> --
> 2.4.6
>

What happens later on if irq == 0? Does irq_set_irq_wake() fail?

Bart