[PATCH v2 2/6] genirq: fix irqchip_set_wake_parent if IRQCHIP_SKIP_SET_WAKE

[Sudeep Holla]

On 12/08/15 18:45, Grygorii Strashko wrote:
> The irqchip_set_wake_parent should not fail if IRQ chip
> specifies IRQCHIP_SKIP_SET_WAKE. Otherwise, IRQ wakeup
> configuration can't be propagated properly through IRQ
> domains hierarchy.
>
> In case of TI OMAP DRA7 the issue reproduced with following
> configuration:
> ARM GIC<-OMAP wakeupgen<-TI CBAR<-GPIO<-GPIO pcf857x<-gpio_key
>
> gpio_key is wakeup source
>
> Failure is reproduced during suspend/resume to RAM:
> suspend:
>   - gpio_keys_suspend
>     enable_irq_wake
>       + pcf857x_irq_set_wake
>         + omap_gpio_wake_enable
>           + TI CBAR irq_chip_set_wake_parent
>             + OMAP wakeupgen has no .irq_set_wake()
>             and -ENOSYS will be returned
>
> resume:
>   - gpio_keys_resume
>     + disable_irq_wake
>       + irq_set_irq_wake
>         + WARN(1, "Unbalanced IRQ %d wake disable\n", irq);
>
> Fixes: 08b55e2a9208 ('genirq: Add irqchip_set_wake_parent')
> Signed-off-by: Grygorii Strashko <grygorii.strashko at ti.com>
> ---
>   kernel/irq/chip.c | 4 ++++
>   1 file changed, 4 insertions(+)
>
> diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
> index 6de638b..bdb1b9d 100644
> --- a/kernel/irq/chip.c
> +++ b/kernel/irq/chip.c
> @@ -1024,6 +1024,10 @@ int irq_chip_set_vcpu_affinity_parent(struct irq_data *data, void *vcpu_info)
>   int irq_chip_set_wake_parent(struct irq_data *data, unsigned int on)
>   {
>   	data = data->parent_data;
> +
> +	if (irq_data_get_irq_chip(data)->flags & IRQCHIP_SKIP_SET_WAKE)
> +		return 0;
> +

[Nit] I think the irq core can access data->chip directly. Either way,
it's better to be consistent, the statement following doesn't use helper
function.

Otherwise looks good to me.

Regards,
Sudeep

>   	if (data->chip->irq_set_wake)
>   		return data->chip->irq_set_wake(data, on);
>
>