Add documentation for the WMI bus sysfs interface so userspace applications can use it to access additional data about WMI devices. Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> Signed-off-by: Armin Wolf <W_Armin@xxxxxx> --- Documentation/ABI/testing/sysfs-bus-wmi | 81 +++++++++++++++++++++++++ MAINTAINERS | 1 + 2 files changed, 82 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-wmi diff --git a/Documentation/ABI/testing/sysfs-bus-wmi b/Documentation/ABI/testing/sysfs-bus-wmi new file mode 100644 index 000000000000..aadb35b82198 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-wmi @@ -0,0 +1,81 @@ +What: /sys/bus/wmi/devices/.../driver_override +Date: February 2024 +Contact: Armin Wolf <W_Armin@xxxxxx> +Description: + This file allows the driver for a device to be specified which + will override standard ID table matching. + When specified, only a driver with a name matching the value + written to driver_override will have an opportunity to bind + to the device. + The override is specified by writing a string to the + driver_override file (echo wmi-event-dummy > driver_override). + The override may be cleared with an empty string (echo > \ + driver_override) which returns the device to standard matching + rules binding. + Writing to driver_override does not automatically unbind the + device from its current driver or make any attempt to automatically + load the specified driver. If no driver with a matching name is + currently loaded in the kernel, the device will not bind to any + driver. + This also allows devices to opt-out of driver binding using a + driver_override name such as "none". Only a single driver may be + specified in the override, there is no support for parsing delimiters. + +What: /sys/bus/wmi/devices/.../modalias +Date: November 20:15 +Contact: Andy Lutomirski <luto@xxxxxxxxxx> +Description: + This file contains the MODALIAS value emitted by uevent for a + given WMI device. + + Format: wmi:XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX. + +What: /sys/bus/wmi/devices/.../guid +Date: November 2015 +Contact: Andy Lutomirski <luto@xxxxxxxxxx> +Description: + This file contains the GUID used to match WMI devices to + compatible WMI drivers. This GUID is not necessarily unique + inside a given machine, it is solely used to identify the + interface exposed by a given WMI device. + +What: /sys/bus/wmi/devices/.../object_id +Date: November 2015 +Contact: Andy Lutomirski <luto@xxxxxxxxxx> +Description: + This file contains the WMI object ID used internally to construct + the ACPI method names used by non-event WMI devices. It contains + two ASCII letters. + +What: /sys/bus/wmi/devices/.../notify_id +Date: November 2015 +Contact: Andy Lutomirski <luto@xxxxxxxxxx> +Description: + This file contains the WMI notify ID used internally to map ACPI + events to WMI event devices. It contains two ASCII letters. + +What: /sys/bus/wmi/devices/.../instance_count +Date: November 2015 +Contact: Andy Lutomirski <luto@xxxxxxxxxx> +Description: + This file contains the number of WMI object instances being + present on a given WMI device. It contains a non-negative + number. + +What: /sys/bus/wmi/devices/.../expensive +Date: November 2015 +Contact: Andy Lutomirski <luto@xxxxxxxxxx> +Description: + This file contains a boolean flag signaling if interacting with + the given WMI device will consume significant CPU resources. + The WMI driver core will take care of enabling/disabling such + WMI devices. + +What: /sys/bus/wmi/devices/.../setable +Date: May 2017 +Contact: Darren Hart (VMware) <dvhart@xxxxxxxxxxxxx> +Description: + This file contains a boolean flags signaling the data block + aassociated with the given WMI device is writable. If the + given WMI device is not associated with a data block, then + this file will not exist. diff --git a/MAINTAINERS b/MAINTAINERS index 09ff0dfd65cb..4f76d6a5d348 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -392,6 +392,7 @@ ACPI WMI DRIVER M: Armin Wolf <W_Armin@xxxxxx> L: platform-driver-x86@xxxxxxxxxxxxxxx S: Maintained +F: Documentation/ABI/testing/sysfs-bus-wmi F: Documentation/driver-api/wmi.rst F: Documentation/wmi/ F: drivers/platform/x86/wmi.c -- 2.39.2
