Re: [RFC PATCH 0/9] Add ACPI _DSD and unified device properties support

From: Mika Westerberg
Date: Sun Aug 17 2014 - 02:55:55 EST


On Sat, Aug 16, 2014 at 09:53:50AM +0300, Mika Westerberg wrote:
> The recent publication of the ACPI 5.1 specification [1] adds a reserved name
> for Device Specific Data (_DSD, Section 6.2.5). This mechanism allows for
> passing arbitrary hardware description data to the OS. The exact format of the
> _DSD data is specific to the UUID paired with it [2].
>
> An ACPI Device Properties UUID has been defined [3] to provide a format
> compatible with existing device tree schemas. The purpose for this was to allow
> for the reuse of the existing schemas and encourage the development of firmware
> agnostic device drivers.
>
> This series accomplishes the following (as well as some other dependencies):
>
> * Add _DSD support to the ACPI core
> This simply reads the UUID and the accompanying Package
>
> * Add ACPI Device Properties _DSD format support
> This understands the hierarchical key:value pair structure
> defined by the Device Properties UUID
>
> * Add a unified device properties API with ACPI and OF backends
> This provides for the firmware agnostic device properties
> Interface to be used by drivers
>
> * Provides 2 example drivers that were previously Device Tree aware that
> can now be used with either Device Tree or ACPI Device Properties. The
> both drivers use an arbitrary _HID.
>
> This has been tested on Minnowboard with relevant parts of the modified
> DSDT at the end of this email.
>
> This series does not provide for a means to append to a system DSDT. That
> will ultimately be required to make the most effective use of the _DSD
> mechanism. Work is underway on that as a separate effort.
>
> [1] http://www.uefi.org/sites/default/files/resources/ACPI_5_1release.pdf
> [2] http://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel.htm
> [3] http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf

For some reason this series never reached the mailing lists intented, so
I re-sent the series with shorter CC list to LKML, linux-acpi and
devicetree lists.

LKML thread is here:

https://lkml.org/lkml/2014/8/17/10

Sorry for the inconvenience.
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