Re: [linux-pm] [patch] pm: fix runtime powermanagement's /sys interface

Pavel Machek
2006-01-06T16:20:23Z

On Pá 06-01-06 06:34:14, Tom Marshall wrote:
> > > I have a firewire controller in a desktop system, and a ATI Radeon in a
> > > T42 that support D1 and D2..
> >
> > Ok, now we have a concrete example. So Radeon supports D1. But putting
> > radeon into D1 means you probably want to blank your screen and turn
> > the backlight off; that takes *long* time anyway. So you can simply
> > put your radeon into D3 and save a bit more power.
> >
> > So yes, Radeon supports D1, but we probably do not want to use it.
>
> I understand this is a theoretical argument. However, in reality, a
> significant number of T42 owners get less than 12 hours of battery life in
> S3 suspend because the Radeon chip sucks a huge amount of power with the
> current code. We would be eternally grateful if someone could figure out
> why only some models are affected and, more importantly, submit a patch that
> will reliably enter D2 (or D3 if it is supported?) for all Radeon 7500
> chips. I've found a couple patches that were submitted to this list but,
> for whatever reason, nobody seems to have found a solution that is
> acceptable yet. I've been manually patching my kernels with code to enter
> D2 for the last year or so, and from the volume of google results, it looks
> like quite a lot of other folks are doing the same... :(

We were talking runtime pm here.
Pavel

--
Thanks, Sharp!