Re: [PATCH 0/4]Bind physical devices with ACPI devices - take 2

Len Brown
2005-01-06T04:00:55Z

On Tue, 2005-01-04 at 21:50, Li Shaohua wrote:
> Hi,
> The series of patches implement binding physical devices with ACPI
> devices. With it, device drivers can utilize methods provided by
> firmware (ACPI). These patches are against 2.6.10, please give your
> comments.

I think we'll save some significant power when ACPI D-states
are invoked for the devices that supply them. While many
PCI devices support PCI power management and thus don't need/use
ACPI D-states, I think it will be even more important to add
this functionality to the legacy devices which never have
PCI power management and thus always depend on ACPI for D-states.

It looks like some device drivers scribble on dev->platform_data;
and we need to fix those drivers before deploying this patch.
Alternatively, we could add a new field to struct device,
but then we'd probably never get rid of it...

I'm a little unformforable with platform_notify
and platform_notify_remove available as globals.
We should probably BUG_ON if we
find them set before ACPI writes on them.

We'll need to update this patch to handle erroneous
but real platforms that don't have _BBN
by using _CRS to get PCI bus number.

Unclear to me if/how this association of ACPI capability
should be reflected in the sysfs device tree.

thanks,
-Len