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-rw-r--r--Documentation/ABI/testing/dell-smbios-wmi41
-rw-r--r--Documentation/ABI/testing/sysfs-platform-dell-smbios21
-rw-r--r--Documentation/ABI/testing/sysfs-platform-intel-wmi-thunderbolt11
-rw-r--r--Documentation/admin-guide/thunderbolt.rst15
4 files changed, 88 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/dell-smbios-wmi b/Documentation/ABI/testing/dell-smbios-wmi
new file mode 100644
index 000000000000..fc919ce16008
--- /dev/null
+++ b/Documentation/ABI/testing/dell-smbios-wmi
@@ -0,0 +1,41 @@
+What: /dev/wmi/dell-smbios
+Date: November 2017
+KernelVersion: 4.15
+Contact: "Mario Limonciello" <mario.limonciello@dell.com>
+Description:
+ Perform SMBIOS calls on supported Dell machines.
+ through the Dell ACPI-WMI interface.
+
+ IOCTL's and buffer formats are defined in:
+ <uapi/linux/wmi.h>
+
+ 1) To perform an SMBIOS call from userspace, you'll need to
+ first determine the minimum size of the calling interface
+ buffer for your machine.
+ Platforms that contain larger buffers can return larger
+ objects from the system firmware.
+ Commonly this size is either 4k or 32k.
+
+ To determine the size of the buffer read() a u64 dword from
+ the WMI character device /dev/wmi/dell-smbios.
+
+ 2) After you've determined the minimum size of the calling
+ interface buffer, you can allocate a structure that represents
+ the structure documented above.
+
+ 3) In the 'length' object store the size of the buffer you
+ determined above and allocated.
+
+ 4) In this buffer object, prepare as necessary for the SMBIOS
+ call you're interested in. Typically SMBIOS buffers have
+ "class", "select", and "input" defined to values that coincide
+ with the data you are interested in.
+ Documenting class/select/input values is outside of the scope
+ of this documentation. Check with the libsmbios project for
+ further documentation on these values.
+
+ 6) Run the call by using ioctl() as described in the header.
+
+ 7) The output will be returned in the buffer object.
+
+ 8) Be sure to free up your allocated object.
diff --git a/Documentation/ABI/testing/sysfs-platform-dell-smbios b/Documentation/ABI/testing/sysfs-platform-dell-smbios
new file mode 100644
index 000000000000..205d3b6361e0
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-platform-dell-smbios
@@ -0,0 +1,21 @@
+What: /sys/devices/platform/<platform>/tokens/*
+Date: November 2017
+KernelVersion: 4.15
+Contact: "Mario Limonciello" <mario.limonciello@dell.com>
+Description:
+ A read-only description of Dell platform tokens
+ available on the machine.
+
+ Each token attribute is available as a pair of
+ sysfs attributes readable by a process with
+ CAP_SYS_ADMIN.
+
+ For example the token ID "5" would be available
+ as the following attributes:
+
+ 0005_location
+ 0005_value
+
+ Tokens will vary from machine to machine, and
+ only tokens available on that machine will be
+ displayed.
diff --git a/Documentation/ABI/testing/sysfs-platform-intel-wmi-thunderbolt b/Documentation/ABI/testing/sysfs-platform-intel-wmi-thunderbolt
new file mode 100644
index 000000000000..8af65059d519
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-platform-intel-wmi-thunderbolt
@@ -0,0 +1,11 @@
+What: /sys/devices/platform/<platform>/force_power
+Date: September 2017
+KernelVersion: 4.15
+Contact: "Mario Limonciello" <mario.limonciello@dell.com>
+Description:
+ Modify the platform force power state, influencing
+ Thunderbolt controllers to turn on or off when no
+ devices are connected (write-only)
+ There are two available states:
+ * 0 -> Force power disabled
+ * 1 -> Force power enabled
diff --git a/Documentation/admin-guide/thunderbolt.rst b/Documentation/admin-guide/thunderbolt.rst
index 5c62d11d77e8..de50a8561774 100644
--- a/Documentation/admin-guide/thunderbolt.rst
+++ b/Documentation/admin-guide/thunderbolt.rst
@@ -221,3 +221,18 @@ The driver will create one virtual ethernet interface per Thunderbolt
port which are named like ``thunderbolt0`` and so on. From this point
you can either use standard userspace tools like ``ifconfig`` to
configure the interface or let your GUI to handle it automatically.
+
+Forcing power
+-------------
+Many OEMs include a method that can be used to force the power of a
+thunderbolt controller to an "On" state even if nothing is connected.
+If supported by your machine this will be exposed by the WMI bus with
+a sysfs attribute called "force_power".
+
+For example the intel-wmi-thunderbolt driver exposes this attribute in:
+ /sys/devices/platform/PNP0C14:00/wmi_bus/wmi_bus-PNP0C14:00/86CCFD48-205E-4A77-9C48-2021CBEDE341/force_power
+
+ To force the power to on, write 1 to this attribute file.
+ To disable force power, write 0 to this attribute file.
+
+Note: it's currently not possible to query the force power state of a platform.