Re: [PATCH 08/15] genirq: Add runtime power management support for IRQ chips

[Jon Hunter <jonathanh@nvidia.com>]

On 18/03/16 17:52, Grygorii Strashko wrote:
> On 03/18/2016 04:56 PM, Jon Hunter wrote:
>>
>> On 18/03/16 14:40, Jon Hunter wrote:
>>> On 18/03/16 14:23, Grygorii Strashko wrote:
>>>> On 03/18/2016 02:27 PM, Jon Hunter wrote:
>>>>>
>>>>> On 18/03/16 11:11, Grygorii Strashko wrote:
>>
>> [snip]
>>
>>>> oh :( That will require updating of all drivers (and if it will be taken into account that
>>>> wakeup can be configured from sysfs + devm_ - it will be painful).
>>>
>>> Will it? I know that there are a few gpio chips that have some hacked
>>> ways to get around the PM issue, but I wonder how many drivers this
>>> really impacts. What sysfs entries are you referring too?
> 
> echo enabled > /sys/devices/platform/44000000.ocp/48020000.serial/tty/ttyS2/power/wakeup
> 
>>
>> Thinking about this some more, yes I guess it would impact all drivers
>> that use a gpio but don't use it for a wake-up. I could see that could
>> be a few drivers indeed.
> 
> yep. I've just tested it
> - gpio was requested through sysfs and configured as IRQ
> - do suspend
> 
> the same is if GPIO is requested as IRQ only and not configured as wakeup source 
> 
> [  319.669760] PM: late suspend of devices complete after 0.213 msecs
> [  319.671195] irq 191 has no wakeup set and has not been freed!
> [  319.673453] PM: noirq suspend of devices complete after 2.258 msecs
> 
> this is very minimal configuration - the regular one is at ~30-50 devices
> most of them will use IRQ and only ~10% are used as wakeup sources.

Then it is working as intended :-)

However, if this is too verbose for some irqchips, then as I mentioned
we can have a flag to avoid these messages.

Cheers
Jon