[PATCH] [JBT6K74] add framebuffer blanking notifier
Michael 'Mickey' Lauer
mickey at openmoko.org
Wed Oct 8 12:26:45 CEST 2008
Am Mittwoch, den 08.10.2008, 11:18 +0100 schrieb Andy Green:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> Somebody in the thread at some point said:
> | This patch adds a framebuffer notifier in order to detect
> | FB_BLANK events and switch the JBT6K74 LCM controller into
> | its power saving mode.
> | This has the potential of saving something like 50mW during screen blank.
> | + struct notifier_block fb_notif;
> Thanks, that's educational, I never met it before; it certainly made for
> a short patch. I sent it on stable.
> The only thing I guess to be aware of is that this is disconnected from
> /sys control of backlight device status unless I missed a point
> somewhere, it means that framebuffer blanking is now better for power
> than turning down backlight by /sys and should be preferred.
What does that mean for userland? AFAICT echo "1"
>/sys/class/backlight/whatever/bl_power should give the maximum power
savings -- no?
More information about the openmoko-kernel