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>
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>
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>
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article is outdated and causes people to still submit new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>
