Messages in this thread | | | From | "Rafael J. Wysocki" <> | Subject | Re: [PATCH -mm 6/7] PM: Remove power_state.event checks from suspend core code | Date | Sun, 17 Jun 2007 21:26:30 +0200 |
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On Friday, 15 June 2007 23:57, Rafael J. Wysocki wrote: > On Friday, 15 June 2007 04:00, Alan Stern wrote: > > On Fri, 15 Jun 2007, Rafael J. Wysocki wrote: > > > > > On Thursday, 14 June 2007 16:21, David Brownell wrote: > > > > On Wednesday 13 June 2007, Rafael J. Wysocki wrote: > > > > > From: Rafael J. Wysocki <rjw@sisk.pl> > > > > > > > > > > The suspend routines should be called for every device during a system sleep > > > > > transition, regardless of the device's state, so that drivers can regard these > > > > > method calls as notifications that the system is about to go to sleep, rather > > > > > than as directives to put their devices into the 'off' state. > > > > > > > > Did you audit all the drivers to make sure this won't break things? > > > > Like for example through inappropriate pci_save_state() calls? > > > > > > I did, but not very carefully. > > > > > > > I'd really expect this patch would break things... > > > > > > Well, in that case I'll have a closer look at them. > > > > It might not be all that bad. One would expect problems to occur only > > in cases where devices were already suspended at the time of a system > > sleep transition. Since relatively few drivers currently implement > > runtime PM -- and those that do are likely to be more careful about > > not blindly making state changes -- there might not be too much > > trouble. > > Yes, in fact I've had no problems related to that so far (tested the patch on > four different machines).
It seems the drivers for which that could be relevant do the checks as needed.
Greetings, Rafael
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