Re: A desktop environment[1] kernel wishlist

From: One Thousand Gnomes
Date: Thu Oct 30 2014 - 19:25:45 EST


O> The kernel receives an interrupt, likely on a different device. Again,
> I'm talking about "legacy" devices, for which suspend is actually a
> state. If the device is only in low-power mode, you'd probably get the
> event on the input device, which is accessible from user-space.

I don't believe so - the firmware ate it.

> Knowing why the Wi-Fi card woke up is also important when there isn't a
> full "suspend" state. As was mentioned, it's useful for power debugging,
> but it's also useful because that tells things outside the network card
> driver what happened.

Wifi devices that are smart generally have a fair bit of info they
provide themselves on this. In particular if you are using a deep idle
type behaviour they may well wake every minute or so just to poke a
packet out to keep any NAT mapping alive.

> As I mentioned in more recent emails on this thread, maybe we don't want
> to know what woke the system up, but knowing that a wake-up event
> occurred on this device, at this time, would allow us to make the
> software act accordingly. The fact that we don't know that means that we
> cannot take appropriate action.

What woke the system up may also not be a singular item. Suppose the
alarm goes off as the user opens the lid and the wireless gets a wakeup
packet in the same window ?

Alan
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