commit c2891f15fdc1a18220477485e2fe2f8a84a51bc2
author Duncan Laurie <dlaurie@google.com> Wed Apr 29 12:34:38 2020 -0700
committer Duncan Laurie <dlaurie@chromium.org> Fri May 22 01:48:16 2020 +0000
tree 603434505b52e5f6f04f7162e41e699022c665e1
parent 526880754faa1246e97e0bd1d836ecc1738e8c90

drivers/intel/soundwire: Add Intel SoundWire controller driver

This driver provides support for Intel SoundWire controllers.  It is
intended to be used by multiple Intel SoCs and relies on retrieving
controller/master information from the SoC itself.  As such it
provides a function that must be implemented by the SoC to fill out
this structure.

The Intel SoundWire driver in the Linux kernel expects firmware to
inform it which master links are unused by adding a custom property
to the link descriptor.  This is done by looking for any children
attached to the device that use each link and disabling the ones
that are unused.

Mainboards will enable this driver and define the controller in
devicetree.cb in order provide the required ACPI tables, but the
mainboard should not need to provide any configuration itself as that
should all come from the SoC directly.

This was tested with the volteer board by adding this controller and a
codec to devicetree.cb and ensuring that the properties are all present,
including the custom properties for the device clock and quirk mask for
disabled links.

Device (SNDW)
{
    Name (_ADR, 0x40000003)
    Name (_CID, Package ()  { "PRP0001", "PNP0A05" })
    Name (_DDN, "Intel SoundWire Controller")
    Name (_DSD, Package ()
    {
        ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
        Package () {
            Package () { "mipi-sdw-sw-interface-revision", 0x00010000 },
            Package () { "mipi-sdw-master-count", 0x04 }
        },
        ToUUID ("dbb8e3e6-5886-4ba6-8795-1319f52a966b"),
        Package () {
            Package () { "mipi-sdw-link-0-subproperties", "LNK0" },
            Package () { "mipi-sdw-link-1-subproperties", "LNK1" },
            Package () { "mipi-sdw-link-2-subproperties", "LNK2" },
            Package () { "mipi-sdw-link-3-subproperties", "LNK3" },
        }
    }
    Name (LNK0, Package ()
    {
        ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
        Package () {
            Package () { "mipi-sdw-clock-stop-mode0-supported", One },
            [...]
            Package () { "intel-sdw-ip-clock", 0x0249F000 },
            Package () { "intel-quirk-mask", Zero },
        }
    }
    [...]
}

BUG=b:146482091

Signed-off-by: Duncan Laurie <dlaurie@google.com>
Change-Id: I4b4f843a7e5ea170b070a1697c8eedc7c103e127
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40888
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>