On Sun, 26 Sep 2004, David Brownell wrote: > I'd hope the core would focus on system-wide PM policies, an extensible > set that should "at the beginning" include roughly: > > - Everything always on. ACPI-friendly. "tune for fastest speeds". > Fair to say this is today's Linux policy default.
This is what I've called power-On. > - Nothing on unless it needs to be. "tune for least power". > Needs device-specific PM framework improvements, including > wakeup support. Both PCI and USB could use this policy, if > Linux cooperates; also the host system CPU(s). This is basically selective-standby, what I've called power-Low. > - Inactive, fast resume: "standby", "big sleep", "suspend-to-ram" Standby is system-wide power-Low. Suspend-to-ram is system-wide power-Off (except for the RAM refresh, obviously). > - Inactive, slow resume: "off", "deep sleep", "suspend-to-disk" What I've called power-Off. > Within each of those system-wide policies, any device could have > several compatible device power level. "Least power" should in > some common cases go transparently in and out of "standby", > given wakeup mechanisms that do their jobs. > > PMcore shouldn't much care about device power state, in fact ... > maybe not even knowing whether a device's current state is > compatible with the desired system-wide PM policy. That'd > be a big change from today's PMcore framework, though not > necessarily in conflict with whatPavel has written in these threads. What you've said agrees pretty much with what I've said. I'm concentrating more on mechanism whereas you're concentrating on policy. The power-level notions I'm using simply encapsulate the essential details of your policies. There's no necessity for them to correspond to any fixed physical power configuration (except for power-Off); one PCI device might implement power-Low as D0 while another implements it as D3hot. Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by: YOU BE THE JUDGE. Be one of 170 Project Admins to receive an Apple iPod Mini FREE for your judgement on who ports your project to Linux PPC the best. Sponsored by IBM. Deadline: Sept. 24. Go here: http://sf.net/ppc_contest.php _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
