Re: [PATCH 2/7] gpio: omap: fix error handling in omap_gpio_irq_type

[Javier Martinez Canillas <javier@xxxxxxxxxxxx>]

Hello Grygorii,

On Fri, May 22, 2015 at 4:35 PM, Grygorii Strashko
<grygorii.strashko@xxxxxxxxxx> wrote:
> The GPIO bank will be kept powered in case if input parameters
> are invalid or error occurred in omap_gpio_irq_type.
>
> Hence, fix it by ensuring that GPIO bank will be unpowered
> in case of errors and add additional check of value returned
> from omap_set_gpio_triggering().
>
> Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxxxxxx>
> ---
>  drivers/gpio/gpio-omap.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
> index bb60cbc..f6cc638 100644
> --- a/drivers/gpio/gpio-omap.c
> +++ b/drivers/gpio/gpio-omap.c
> @@ -488,9 +488,6 @@ static int omap_gpio_irq_type(struct irq_data *d, unsigned type)
>         unsigned long flags;
>         unsigned offset = d->hwirq;
>
> -       if (!BANK_USED(bank))
> -               pm_runtime_get_sync(bank->dev);
> -
>         if (type & ~IRQ_TYPE_SENSE_MASK)
>                 return -EINVAL;
>
> @@ -498,12 +495,18 @@ static int omap_gpio_irq_type(struct irq_data *d, unsigned type)
>                 (type & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH)))
>                 return -EINVAL;
>
> +       if (!BANK_USED(bank))
> +               pm_runtime_get_sync(bank->dev);
> +
>         spin_lock_irqsave(&bank->lock, flags);
>         retval = omap_set_gpio_triggering(bank, offset, type);
> +       if (retval)

At this point the bank->lock spinlock is held so you need to add a
spin_unlock_irqrestore() in the error path.

> +               goto error;
>         omap_gpio_init_irq(bank, offset);
>         if (!omap_gpio_is_input(bank, offset)) {
>                 spin_unlock_irqrestore(&bank->lock, flags);
> -               return -EINVAL;
> +               retval = -EINVAL;
> +               goto error;
>         }
>         spin_unlock_irqrestore(&bank->lock, flags);
>
> @@ -512,6 +515,11 @@ static int omap_gpio_irq_type(struct irq_data *d, unsigned type)
>         else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
>                 __irq_set_handler_locked(d->irq, handle_edge_irq);
>
> +       return 0;
> +
> +error:
> +       if (!BANK_USED(bank))
> +               pm_runtime_put(bank->dev);
>         return retval;
>  }
>
> --

But you are correct about the runtime PM bug so after addressing the
above comment, feel free to add:

Acked-by: Javier Martinez Canillas <javier@xxxxxxxxxxxx>

Best regards,
Javier
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