Re: [PATCH] PM: Make it possible to avoid wakeup events from being lost

[Pavel Machek <pavel@ucw.cz>]

Hi!

> @@ -114,3 +114,17 @@ Description:
>  		if this file contains "1", which is the default.  It may be
>  		disabled by writing "0" to this file, in which case all devices
>  		will be suspended and resumed synchronously.
> +
> +What:		/sys/power/wakeup_count
> +Date:		July 2010
> +Contact:	Rafael J. Wysocki <rjw@sisk.pl>
> +Description:
> +		The /sys/power/wakeup_count file allows user space to avoid
> +		losing wakeup events when transitioning the system into a sleep
> +		state.  Reading from it returns the current number of registered
> +		wakeup events and it blocks if some wakeup events are being
> +		processed at the time the file is read from.  Writing to it
> +		will only succeed if the current number of wakeup events is
> +		equal to the written value and, if successful, will make the
> +		kernel abort a subsequent transition to a sleep state if any
> +		wakeup events are reported after the write has returned.

I assume that second suspend always succeeds?

I can't say I quite like the way two sysfs files interact with each
other, but it is certainly better then wakelocks...

Maybe we should create sys_suspend()?

-- 
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