Re: [PATCH 1/5] driver core / ACPI: Move ACPI support to core device and driver types

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Wednesday, October 31, 2012 09:24:07 AM Greg Kroah-Hartman wrote:
> On Wed, Oct 31, 2012 at 10:38:29AM +0100, Rafael J. Wysocki wrote:
> > From: Mika Westerberg <mika.westerberg@linux.intel.com>
> > 
> > With ACPI 5 we are starting to see devices that don't natively support
> > discovery but can be enumerated with the help of the ACPI namespace.
> > Typically, these devices can be represented in the Linux device driver
> > model as platform devices or some serial bus devices, like SPI or I2C
> > devices.
> > 
> > Since we want to re-use existing drivers for those devices, we need a
> > way for drivers to specify the ACPI IDs of supported devices, so that
> > they can be matched against device nodes in the ACPI namespace.  To
> > this end, it is sufficient to add a pointer to an array of supported
> > ACPI device IDs, that can be provided by the driver, to struct device.
> > 
> > Moreover, things like ACPI power management need to have access to
> > the ACPI handle of each supported device, because that handle is used
> > to invoke AML methods associated with the corresponding ACPI device
> > node.  The ACPI handles of devices are now stored in the archdata
> > member structure of struct device whose definition depends on the
> > architecture and includes the ACPI handle only on x86 and ia64. Since
> > the pointer to an array of supported ACPI IDs is added to struct
> > device_driver in an architecture-independent way, it is logical to
> > move the ACPI handle from archdata to struct device itself at the same
> > time.  This also makes code more straightforward in some places and
> > follows the example of Device Trees that have a poiter to struct
> > device_node in there too.
> > 
> > This changeset is based on Mika Westerberg's work.
> > 
> > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > ---
> >  arch/ia64/include/asm/device.h |    3 ---
> >  arch/x86/include/asm/device.h  |    3 ---
> >  drivers/acpi/glue.c            |   14 ++++++--------
> >  include/acpi/acpi_bus.h        |    2 +-
> >  include/linux/device.h         |    4 ++++
> >  5 files changed, 11 insertions(+), 15 deletions(-)
> 
> The driver core pieces look fine to me:
> 
> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Great, thanks!

I wonder if the x86 and/or ia64 maintainers have any reservations?

Rafael


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