Hi! > > > Actually, it just occurred to me that if we're waiting for a system > > > timer and can hand that off to a suitable timer in the PMIC then we can > > > do a suspend to RAM for the deep idle state from the hardware point of > > > view. > > > > Yep. At LinuxCon Cambridge two years ago, we had a discussion about > > whether it would be possible to enter ACPI S-states from CPUIdle (or some > > idle governor) on Intel chips. If I remember correctly, the conclusion > > was that ACPI always disables the screen/backlight, so it would only be > > useful for situations where that was acceptable. Well, auto suspending when screensaver is active would still be useful. (And IIRC some machines kept screen on when in S-state unless driver powered it down... but that might be S1. > The reason why you can't enter ACPI S-states from CPUidle is because you > need to go out of the idle loop to execute some ACPI-specific stuff. Which > is not even specific to Intel chips, but to ACPI in general. The code was little tricky/unclean, but it "worked" for me at one point... I called it "sleepy linux". Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
