diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/dell-smbios-wmi | 41 | ||||
| -rw-r--r-- | Documentation/ABI/testing/sysfs-platform-dell-smbios | 21 | ||||
| -rw-r--r-- | Documentation/ABI/testing/sysfs-platform-intel-wmi-thunderbolt | 11 | ||||
| -rw-r--r-- | Documentation/admin-guide/thunderbolt.rst | 15 |
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. |