Re: [RFC PATCH] PM / Runtime: runtime: Add sysfs option for forcing runtime suspend

[Pavel Machek <pavel@ucw.cz>]

On Mon 2015-09-21 10:38:46, Alan Stern wrote:
> On Mon, 21 Sep 2015, Pavel Machek wrote:
> 
> > > > In fact, then, what you need seems to be the feature discussed by Alan
> > > > and me some time ago allowing remote wakeup do be disabled for runtime
> > > > PM from user space as that in combination with autosuspend should
> > > > address your use case.
> > > 
> > > That, plus they want the touchscreen to go into runtime suspend 
> > > whenever the screen is off (was this not the main reason for the 
> > > patch?).
> > > 
> > > It seems to me that it should be possible to arrange for this to happen 
> > > simply by making userspace close the touchscreen device when the screen 
> > > is turned off.  Or am I missing something?
> > 
> > Well... that's not what existing userspace expects. Your X windows
> > server will not close the touchscreen.
> 
> Surely that's a userspace issue, rather than a kernel problem?  The X
> server does have some notion of power management and power savings; why
> not extend that notion to include touchscreens?

Well... once upon a time, it was kernel job to mask differences
between different hardware platforms.

In a way, the hardware is "buggy" -- if your mouse clicked randomly
when you were not holding it in your hand it would be buggy... and it
would be nice for kernel to fix that "bug". 

								Pavel
-- 
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