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2026-01-20platform/wmi: Update driver development guideArmin Wolf
New WMI drivers should use the new buffer-based WMI API instead of the deprecated ACPI-based API. Update the driver development guide to recommend the buffer-based API to driver developers and explain the purpose of struct wmi_buffer. Also update the ACPI interface documentation to describe the conversion rules for converting ACPI objects into WMI buffers. Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Armin Wolf <W_Armin@gmx.de> Link: https://patch.msgid.link/20260116204116.4030-10-W_Armin@gmx.de Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-11-10platform/x86: msi-wmi-platform: Fix typo in WMI GUIDArmin Wolf
The WMI driver core only supports GUID strings containing only uppercase characters, however the GUID string used by the msi-wmi-platform driver contains a single lowercase character. This prevents the WMI driver core from matching said driver to its WMI device. Fix this by turning the lowercase character into a uppercase character. Also update the WMI driver development guide to warn about this. Reported-by: Antheas Kapenekakis <lkml@antheas.dev> Fixes: 9c0beb6b29e7 ("platform/x86: wmi: Add MSI WMI Platform driver") Tested-by: Antheas Kapenekakis <lkml@antheas.dev> Signed-off-by: Armin Wolf <W_Armin@gmx.de> Link: https://patch.msgid.link/20251110111253.16204-3-W_Armin@gmx.de Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-02-24platform/x86: wmi: Update documentation regarding the GUID-based APIArmin Wolf
Warn WMI driver developers to not use GUID-based and non-GUID-based functions for querying WMI data blocks and handling WMI events simultaneously on the same device, as this will corrupt the WMI device state and might thus lead to erratic behaviour. Signed-off-by: Armin Wolf <W_Armin@gmx.de> Link: https://lore.kernel.org/r/20250216193251.866125-9-W_Armin@gmx.de Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-01-09docs: platform/x86: wmi: mention tool for invoking WMI methodsHridesh MG
Add a reference to WMIExplorer, a tool useful for inspecting and invoking WMI methods on Windows. This can assist developers in testing and understanding WMI device functionality when porting drivers to Linux. Signed-off-by: Hridesh MG <hridesh699@gmail.com> Reviewed-by: Armin Wolf <W_Armin@gmx.de> Link: https://lore.kernel.org/r/20250101092730.87160-1-hridesh699@gmail.com Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2024-10-09platform/x86: wmi: Implement proper shutdown handlingArmin Wolf
When performing a system shutdown under Windows, all WMI clients are terminated. This means that the ACPI BIOS might expect all WMI devices to be disabled when shutting down. Emulate this behaviour by disabling all active WMI devices during shutdown. Also introduce a new WMI driver callback to allow WMI drivers to perform any device-specific actions before disabling the WMI device. Tested on a Dell Inspiron 3505. Signed-off-by: Armin Wolf <W_Armin@gmx.de> Link: https://lore.kernel.org/r/20241005213825.701887-2-W_Armin@gmx.de Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2024-04-08platform/x86: wmi: Add driver development guideArmin Wolf
Since 2010, an LWN article covering WMI drivers exists: https://lwn.net/Articles/391230/ Since the introduction of the modern bus-based interface and other userspace tooling (bmfdec, lswmi, ...), this article is outdated and causes people to still submit new WMI drivers using the deprecated GUID-based interface. Fix this by adding a short guide on how to develop WMI drivers using the modern bus-based interface. Signed-off-by: Armin Wolf <W_Armin@gmx.de> Link: https://lore.kernel.org/r/20240402143059.8456-4-W_Armin@gmx.de Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com>