On Thu, 6 Dec 2007 16:25:57 -0700 Bjorn Helgaas <bjorn.helgaas@xxxxxx> wrote: > PNP: do not stop/start devices in suspend/resume path > > Do not disable PNP devices in the suspend path. We still call > the driver's suspend method, which should prevent further use of > the device, and the protocol suspend method, which may put the > device in a low-power state. > > I'm told that Windows puts devices in a low-power state (Linux > does this in the protocol suspend method), but does not use _DIS > in the suspend path. Other relevant references: > > - In the ACPI 3.0b spec, I can't find any mention of _DIS in > connection with sleep. And Device Object Notifications, > Section 5.6.3, Table 5-43, says we should get a bus check > after awakening if hardware was removed while we slept. > > - This: http://msdn2.microsoft.com/en-us/library/ms810079.aspx > makes a similar point about how the OS re-enumerates devices > as a result of a power state change (3rd last paragraph of > text). > > - This: http://msdn2.microsoft.com/en-us/library/aa489874.aspx > suggests that Windows only stops a device to rebalance hardware > resources. > > Signed-off-by: Bjorn Helgaas <bjorn.helgaas@xxxxxx> > Tested-by: Pierre Ossman <drzeus@xxxxxxxxx> No noticeable issues with suspend or hibernate using this patch. Rgds Pierre
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