Messages in this thread | | | Date | Tue, 1 Apr 2008 10:31:44 -0400 (EDT) | From | Alan Stern <> | Subject | Re: [RFC][PATCH] PM: Introduce new top level suspend and hibernation callbacks (rev. 6) |
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On Tue, 1 Apr 2008, Benjamin Herrenschmidt wrote:
> On Tue, 2008-04-01 at 19:15 +1100, Nigel Cunningham wrote: > > > + * However, drivers may NOT assume anything about the availability of the > > > + * user space at that time and it is not correct to request firmware from > > > + * within @prepare() (it's too late to do that). > > > > That doesn't sound good. It would be good to be able to get drivers to > > request firmware early in the process. > > Agreed. Prepare() should still allow request_firmware and full userspace > communication / helper usage.
Pepare() is called after userspace has been frozen. (Of course, once the freezer goes away this won't matter any more.)
There is a separate notifier chain which drivers can subscribe to; notifications about impending sleeps are sent out while userspace is still alive. Drivers can use that for request_firmware, memory allocation, and other things.
Alan Stern
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