Comment 120 for bug 971061

Following the link:

      https://bugzilla.kernel.org/show_bug.cgi?id=44161

I read that someone noted that AC was reported correctly after suspend, even though the EC events were consumed by the little program on resume.

I'll reply here to that since I don't have an account there:

The reason is because the DSDT method called _WAK (short for "AWAKE"), is called when resuming from sleep. If you look at the code in the DSDT, you'll see that this method checks to see if AC, LID, and Battery have changed since suspend, and issues the corresponding Notify() calls, thus producing the relevant events, when waking up, independently of the EC.

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Juan Manuel