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

From: [email-masked] (Marc Zyngier)
Date: Thu, 13 Aug 2015 11:01:35 +0100

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()

Most importantly, wakeupgen has IRQCHIP_SKIP_SET_WAKE set.

>            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 <[email-masked]>
> ---
>  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;
> +
>  	if (data->chip->irq_set_wake)
>  		return data->chip->irq_set_wake(data, on);
>  
> 

We have a more general issue with chip flags, and how they combine
within a stack of irqchips.

What if you remove the irq_chip_set_wake_parent from the crossbar
driver, and instead set IRQCHIP_SKIP_SET_WAKE?

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...