Re: [PATCH v2 1/1] irqchip: exynos-combiner: Save IRQ enable set on suspend

Krzysztof Kozlowski
2015-06-12T10:42:29Z

On 12.06.2015 19:10, Sudeep Holla wrote:
>
>
> On 12/06/15 06:43, Javier Martinez Canillas wrote:
>> The Exynos interrupt combiner IP loses its state when the SoC enters
>> into a low power state during a Suspend-to-RAM. This means that if a
>> IRQ is used as a source, the interrupts for the devices are disabled
>> when the system is resumed from a sleep state so are not triggered.
>>
>> Save the interrupt enable set register for each combiner group and
>> restore it after resume to make sure that the interrupts are enabled.
>>
>
> Not sure if you need this. IMO it's not clean and redundant though I
> admit many drivers do exactly same thing. I am trying to remove or point
> out those redundant code as irqchip core has options/flags to do what
> you need. I assume there are no wakeup sources connected to this
> combiner.

It may have wake up sources connected. Correct me if I am wrong but (at
least) on Exynos5250 combiner takes care of gpx1 GPIO pins which may be
external interrupts (e.g. power key on Exynos5250 Snow). I didn't check
other boards.

Best regards,
Krzysztof

> Setting irqchip flags should solve this problem. A simple
> patch below should do the job ?
>
> -->8
>
> diff --git a/drivers/irqchip/exynos-combiner.c
> b/drivers/irqchip/exynos-combiner.c
> index 5945223b73fa..c0bcec59f829 100644
> --- a/drivers/irqchip/exynos-combiner.c
> +++ b/drivers/irqchip/exynos-combiner.c
> @@ -111,6 +111,7 @@ static struct irq_chip combiner_chip = {
> #ifdef CONFIG_SMP
> .irq_set_affinity = combiner_set_affinity,
> #endif
> + .flags = IRQCHIP_MASK_ON_SUSPEND,
> };
>
>
>