Unverified Commit dc1ec4fa authored by Mingyou Chen's avatar Mingyou Chen Committed by Ilpo Järvinen
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platform/x86: bitland-mifs-wmi: Add new Bitland MIFS WMI driver 



Add a new driver for Bitland laptops that utilize the MIFS (MiInterface)
WMI interface.

The driver implements several features through the WMI interface:

- Platform Profile: Supports "Quiet", "Balanced", "Performance", and
  "Full Speed" modes. The "Full Speed" mode is intelligently restricted
  based on the AC adapter type (requires DC power, not supported on
  USB-C charging) as required by the hardware.
- Hwmon: Provides monitoring for CPU, GPU, and System fan speeds,
  as well as CPU temperature sensors.
- Keyboard Backlight: Integrated with the LED class device for
  brightness control and provides sysfs attributes for keyboard modes
  (cyclic, fixed, etc.).
- GPU Mode: Allows switching between Hybrid, Discrete, and UMA
  graphics modes via sysfs.
- Hotkeys: Handles WMI events for system hotkeys (Calculator, Browser,
  App launch) using sparse keymaps and reports status changes for
  Airplane mode, Touchpad, and CapsLock.
- Fan Boost: Provides a sysfs interface to force fans to maximum speed.

The driver registers two WMI GUIDs:
- B60BFB48-3E5B-49E4-A0E9-8CFFE1B3434B: Control methods
- 46C93E13-EE9B-4262-8488-563BCA757FEF: Event notifications

Reviewed-by: default avatarArmin Wolf <W_Armin@gmx.de>
Signed-off-by: default avatarMingyou Chen <qby140326@gmail.com>
Link: https://patch.msgid.link/20260323132218.444383-1-qby140326@gmail.com


Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
parent a5877e92

Documentation/wmi/devices/bitland-mifs-wmi.rst

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.. SPDX-License-Identifier: GPL-2.0-or-later



========================================

Bitland MIFS driver (bitland-mifs-wmi)

========================================



Introduction

============





EC WMI interface description

============================



The EC WMI interface description can be decoded from the embedded binary MOF (bmof)

data using the `bmfdec <https://github.com/pali/bmfdec>`_ utility:



::



  class WMIEvent : __ExtrinsicEvent {

  };



  [WMI, Dynamic, Provider("WmiProv"), Locale("MS\\0x40A"), Description("Root WMI HID_EVENT20"), guid("{46c93e13-ee9b-4262-8488-563bca757fef}")]

  class HID_EVENT20 : WmiEvent {

    [key, read] string InstanceName;

    [read] boolean Active;

    [WmiDataId(1), read, write, Description("Package Data")] uint8 EventDetail[8];

  };



  [WMI, Dynamic, Provider("WmiProv"), Locale("MS\\0x40A"), Description("Root WMI HID_EVENT21"), guid("{fa78e245-2c0f-4ca1-91cf-15f34e474850}")]

  class HID_EVENT21 : WmiEvent {

    [key, read] string InstanceName;

    [read] boolean Active;

    [WmiDataId(1), read, write, Description("Package Data")] uint8 EventDetail[8];

  };



  [WMI, Dynamic, Provider("WmiProv"), Locale("MS\\0x40A"), Description("Root WMI HID_EVENT22"), guid("{1dceaf0a-4d63-44bb-bd0c-0d6281bfddc5}")]

  class HID_EVENT22 : WmiEvent {

    [key, read] string InstanceName;

    [read] boolean Active;

    [WmiDataId(1), read, write, Description("Package Data")] uint8 EventDetail[8];

  };



  [WMI, Dynamic, Provider("WmiProv"), Locale("MS\\0x40A"), Description("Root WMI HID_EVENT23"), guid("{3f9e3c26-b077-4f86-91f5-37ff64d8c7ed}")]

  class HID_EVENT23 : WmiEvent {

    [key, read] string InstanceName;

    [read] boolean Active;

    [WmiDataId(1), read, write, Description("Package Data")] uint8 EventDetail[8];

  };



  [WMI, Dynamic, provider("WmiProv"), Locale("MS\\0x409"), Description("Class used to operate firmware interface"), guid("{b60bfb48-3e5b-49e4-a0e9-8cffe1b3434b}")]

  class MICommonInterface {

    [key, read] string InstanceName;

    [read] boolean Active;



    [WmiMethodId(1), Implemented, read, write, Description("Method used to support system functions.")] void MiInterface([in, Description("WMI Interface")] uint8 InData[32], [out] uint8 OutData[30], [out] uint16 Reserved);

  };



Reverse-Engineering the EC WMI interface

========================================



The OEM software can be download from `this link <https://iknow.lenovo.com.cn/detail/429447>`_



Nothing is obfuscated, In this case, `ILSpy <https://github.com/icsharpcode/ILSpy>`_ could be helpful.



WMI Methods (MICommonInterface)

========================================



The ``MICommonInterface`` class (GUID: ``{b60bfb48-3e5b-49e4-a0e9-8cffe1b3434b}``)

is the primary control interface. It uses a 32-byte buffer for both input

(``InData``) and output (``OutData``).



Method Structure

----------------



The data packet follows a standardized format:



+----------+------------------------------------------------------------------+

| Byte     | Description                                                      |

+==========+==================================================================+

| 1        | Method Type: Get (0xFA / 250) or Set (0xFB / 251)                |

+----------+------------------------------------------------------------------+

| 3        | Command ID (Method Name)                                         |

+----------+------------------------------------------------------------------+

| 4 - 31   | Arguments (for Set) or Return Data (for Get)                     |

+----------+------------------------------------------------------------------+





Command IDs

-----------



The following Command IDs are used in the third byte of the buffer:



+----------+-----------------------+------------------------------------------+

| ID       | Name                  | Values / Description                     |

+==========+=======================+==========================================+

| 8        | SystemPerMode         | 0: Balance, 1: Performance, 2: Quiet,    |

|          |                       | 3: Full-speed                            |

+----------+-----------------------+------------------------------------------+

| 9        | GPUMode               | 0: Hybrid, 1: Discrete, 2: UMA           |

+----------+-----------------------+------------------------------------------+

| 10       | KeyboardType          | 0: White, 1: Single RGB, 2: Zone RGB     |

+----------+-----------------------+------------------------------------------+

| 11       | FnLock                | 0: Off, 1: On                            |

+----------+-----------------------+------------------------------------------+

| 12       | TPLock                | 0: Unlock, 1: Lock (Touchpad)            |

+----------+-----------------------+------------------------------------------+

| 13       | CPUGPUSYSFanSpeed     | Returns 12 bytes of fan data:            |

|          |                       | Bytes 4-5: CPU Fan RPM (Little Endian)   |

|          |                       | Bytes 6-7: GPU Fan RPM (Little Endian)   |

|          |                       | Bytes 10-11: SYS Fan RPM (Little Endian) |

+----------+-----------------------+------------------------------------------+

| 16       | RGBKeyboardMode       | 0: Off, 1: Auto Cyclic, 2: Fixed,        |

|          |                       | 3: Custom                                |

+----------+-----------------------+------------------------------------------+

| 17       | RGBKeyboardColor      | Bytes 4, 5, 6: Red, Green, Blue values   |

+----------+-----------------------+------------------------------------------+

| 18       | RGBKeyboardBrightness | 0-10: Brightness Levels, 128: Auto       |

+----------+-----------------------+------------------------------------------+

| 19       | SystemAcType          | 1: Type-C, 2: Circular Hole (DC)         |

+----------+-----------------------+------------------------------------------+

| 20       | MaxFanSpeedSwitch     | Byte 4: Fan Type (0: CPU/GPU, 1: SYS)    |

|          |                       | Byte 5: State (0: Off, 1: On)            |

+----------+-----------------------+------------------------------------------+

| 21       | MaxFanSpeed           | Sets manual fan speed duty cycle         |

+----------+-----------------------+------------------------------------------+

| 22       | CPUThermometer        | Returns CPU Temperature                  |

+----------+-----------------------+------------------------------------------+



WMI Events (HID_EVENT20)

========================



The driver listens for events from the ``HID_EVENT20`` class

(GUID: ``{46c93e13-ee9b-4262-8488-563bca757fef}``). These events are triggered

by hotkeys or system state changes (e.g., plugging in AC power).



Event Structure

---------------



The event data is provided in an 8-byte array (``EventDetail``):



+----------+------------------------------------------------------------------+

| Byte     | Description                                                      |

+==========+==================================================================+

| 0        | Event Type (Always 0x01 for HotKey/Notification)                 |

+----------+------------------------------------------------------------------+

| 1        | Event ID (Corresponds to the Command IDs above)                  |

+----------+------------------------------------------------------------------+

| 2        | Value (The new state or value of the feature)                    |

+----------+------------------------------------------------------------------+



Common Event IDs:

-----------------



Note: reserved event ids are not listed there



+----------+------------------------------------------------------------------+

| Event Id | Description                                                      |

+==========+==================================================================+

| 4        | AirPlane mode change                                             |

+----------+------------------------------------------------------------------+

| 5        | Keyboard brightness change                                       |

+----------+------------------------------------------------------------------+

| 6        | Touchpad state (enabled/disabled) change                         |

+----------+------------------------------------------------------------------+

| 7        | FnLock state (enabled/disabled) change                           |

+----------+------------------------------------------------------------------+

| 8        | Keyboard mode change                                             |

+----------+------------------------------------------------------------------+

| 9        | CapsLock state change                                            |

+----------+------------------------------------------------------------------+

| 13       | NumLock state change                                             |

+----------+------------------------------------------------------------------+

| 14       | ScrollLock state change                                          |

+----------+------------------------------------------------------------------+

| 15       | Performance plan change                                          |

+----------+------------------------------------------------------------------+

| 25       | Display refresh rate change                                      |

+----------+------------------------------------------------------------------+

| 33       | Super key lock state (enabled/disabled) change                   |

+----------+------------------------------------------------------------------+

| 35       | Open control center key                                          |

+----------+------------------------------------------------------------------+



Implementation Details

======================



Performance Modes

-----------------

Changing the performance mode via Command ID 0x08 (SystemPerMode) affects the

power limits (PL1/PL2) and fan curves managed by the Embedded Controller (EC).

Note that the "Full-speed" and "Performance" mode (1, 3) is typically only

available when the system is connected to a DC power source (not USB-C/PD).



In the driver implementation, switch to performance/full-speed mode without

DC power connected will throw the EOPNOTSUPP error.



Graphics Switching

------------------

The ``GPUMode`` (0x09) allows switching between Hybrid (Muxless) and Discrete

(Muxed) graphics. Changing this value usually requires a system reboot to

take effect in the BIOS/Firmware.



Fan Control

-----------

The system supports both automatic EC control and manual overrides. Command ID

0x14 (``MaxFanSpeedSwitch``) is used to toggle manual control, while ID 0x15

sets the actual PWM duty cycle.

drivers/platform/x86/Kconfig

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@@ -113,6 +113,24 @@ config GIGABYTE_WMI 
	  To compile this driver as a module, choose M here: the module will

	  be called gigabyte-wmi.



config BITLAND_MIFS_WMI

	tristate "Bitland MIFS (MiInterface) WMI driver"

	depends on ACPI_WMI

	depends on HWMON

	depends on INPUT

	depends on POWER_SUPPLY

	select ACPI_PLATFORM_PROFILE

	select INPUT_SPARSEKMAP

	help

	  This is a driver for Bitland MiInterface based laptops.



	  It provides the access to the temperature, fan speed, gpu

	  control, keyboard backlight brightness and platform profile

	  via hwmon and sysfs.



	  To compile this driver as a module, choose M here: the module will

          be called bitland-mifs-wmi.



config ACERHDF

	tristate "Acer Aspire One temperature and fan driver"

	depends on ACPI_EC && THERMAL

drivers/platform/x86/Makefile

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@@ -14,6 +14,7 @@ obj-$(CONFIG_NVIDIA_WMI_EC_BACKLIGHT) += nvidia-wmi-ec-backlight.o 
obj-$(CONFIG_XIAOMI_WMI)		+= xiaomi-wmi.o

obj-$(CONFIG_REDMI_WMI)			+= redmi-wmi.o

obj-$(CONFIG_GIGABYTE_WMI)		+= gigabyte-wmi.o

obj-$(CONFIG_BITLAND_MIFS_WMI)		+= bitland-mifs-wmi.o



# Acer

obj-$(CONFIG_ACERHDF)		+= acerhdf.o

drivers/platform/x86/bitland-mifs-wmi.c

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