Re: Power Management framework proposal
From: david
Date: Sun Jul 29 2007 - 18:03:32 EST
On Fri, 27 Jul 2007, Pavel Machek wrote:
Hi!
example 1: a laptop screen
mode capacity power description
0 0 0 off
1 100 100 full brightness
2 70 60 half power to the backlight
3 50 35 quarter power to the backlight
4 30 25 eighth power to the backlight
5 5 10 backlight off.
example 2: a front-panel display on a server (no
variable backlight
control)
mode capacity power description
0 0 0 off
1 100 100 backlight on
2 50 10 backlight off
the problem is: the person who SETS these needs to know
what they mean.
that's what the description is for. this info can be
provided by the driver as part of the list_modes()
function.
That's what /sys/class/backlight/ is for :-).
yes it is, and each type of device is growing it's own, incompatible,
interfaces for controlling things like this. I was aiming to do two
things.
1. head this off and try and get a more common api
2. simplify the confusion that there is with multiple functions needing to
be implemented during the suspend/resume cycle by chaning them from
independant suspend-only functions to being just part of the device
settings
as someone who wrote (part of) a power policy manager;
sorry but you
take away information I need, and in addition the
different API's are
absolutely no big deal.
assuming that nobody else chimes in to disagree with you
I'll accept your judgement and drop the issue.
Just for the record, I agree with Arjan here.
oh well. sorry to take up everyone's time.
David Lang
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