Inhibitions and suspend in powerdevil and plasma-workspace

[Kai Uwe Broulik]

Hi,

as Nate pointed out, suspend inhibition is only about blocking automatic 
suspend, e.g. during a lengthy operation. Explicit user interaction, 
such as pressing the suspend button or closing the lid are never blocked 
by us.

As for Logind, the “challenge” response means that the user can only 
suspend if PolicyKit allows it. What could happen is that a Polkit 
prompt pops up (e.g. “permission is needed to suspend with another user 
logged in” or something) but I don’t see why we would need to handle 
this specially on the Plasma side.

Cheers
Kai Uwe

Am 13.09.25 um 05:34 schrieb SignKirigami:
> Hello everyone, I find it confusing that some inhibitions will prevent system
> from auto suspend, but not manually clicking suspend button, so I try to read
> source code of powerdevil and plasma-workspace.
> 
> As far as I can see, in plasma-workspace there is canSuspend function which
> will check systemd-inhibit from dbus, and return yes when login1 returns yes
> or challenge(some applications requests inhibition will lead to this). Suspend
> button uses this, but because canSuspend treats yes and challenge as the same,
> there is no difference whether systemd inhibition exists, that's why suspend
> button will ignore systemd inhibition.
> 
> In powerdevil, what canSuspend returns is used in function
> loadAllInactiveActions, which will create a new profile with canSuspend and
> give it to suspendsession action, let it determine auto suspend or not. There
> is another mechanism which really works called policyagent. It syncs with
> systemd inhibitions and has its own inhibitions related to settings and old
> program(like ktorrent). When suspendsesstion handles timeout, it checks
> policyagent to determine whether to suspend or not.
> 
> Now I wonder if these really work as expected? Do we need to check systemd
> inhibition and give a warnning before do actual suspend work when inhibition
> exists?