Re: [Resend][PATCH] ACPI / PM: Do not power manage devices in unknown initial states

[Rafael J. Wysocki]

On Friday, February 01, 2013 07:23:52 PM Peter Wu wrote:
> On Thursday 31 January 2013 23:32:40 Rafael J. Wysocki wrote:
> > In general, for ACPI device power management to work, the initial
> > power states of devices must be known (otherwise, we wouldn't be able
> > to keep track of power resources, for example).  Hence, if it is
> > impossible to determine the initial ACPI power states of some
> > devices, they can't be regarded as power-manageable using ACPI.
> > 
> > For this reason, modify acpi_bus_get_power_flags() to clear the
> > power_manageable flag if acpi_bus_init_power() fails and add some
> > extra fallback code to acpi_bus_init_power() to cover broken
> > BIOSes that provide _PS0/_PS3 without _PSC for some devices.
> > 
> > Verified to work on my HP nx6325 that has this problem.
> > 
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> 
> Tested-by: Peter Wu <lekensteyn@xxxxxxxxx>
> 
> I applied it on top of branch linux-next of repo linux-pm.
> 
> Fixes the issue I had with bbswitch in Linux 3.8. Can a backport patch be made 
> available for 3.8?

Yes, after this commit enters the mainline.  Please ping me some time around
3.9-rc1.

Thanks,
Rafael


-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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