Re: [PATCH v15] platform/x86: bitland-mifs-wmi: Add new Bitland MIFS WMI driver

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

On Mon, 23 Mar 2026, Mingyou Chen wrote:

> 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: Armin Wolf <W_Armin@gmx.de>
> Signed-off-by: Mingyou Chen <qby140326@gmail.com>
> ---
> v15:
>   - Capitalize the first letter of "touchpad" in the doc
>   - Fix style issues
>   - Replace manual kfree with __free
> v14:
>   - Add Reviewed-by
> v13:
>   - make laptop_attrs const
> v12:
>   - add depends on INPUT and select INPUT_SPARSEKMAP
>   - code cleanup - remove unnecessary ret variables
>   - add the copyright text and pr_fmt macro
>   - use blocking notifier instead of atomic notifier
>   - pass the platform profile device here instead of the WMI device at bitland_mifs_wmi_suspend
>   - remove unnecessary null checks
>   - pass the platform_profile dev to platform_profile_notify
>   - fetch led brightness from WMI on init led
>   - remove the (const struct bitland_mifs_event *) cast in bitland_mifs_wmi_notify
> v11:
>   - fix checkpatch reported issues
> v10:
>   - After some researches, I acknowledge my device is from Bitland, not
>     Tongfang. Rename the driver to bitland-mifs-wmi
> v9:
>   - Fix style issues in .rst documentation
>   - Rewrite the wmi_call func with correct usage
>   - Use power_supply_is_system_supplied in kernel instead of
>     is_ac_online
>   - Remove the PLATFORM_PROFILE_LAST check in wmi_resume function
>   - Directly return in the hwmon_temp case in hwmon_read function
>   - return -EPROTO on invalid wmi return value in gpu_mode and
>     keyboard brightness
>   - Remove the dev_err debug messages
>   - Rewrite the wmi_notify method with .notify_new callback in
>     linux-next
>   - Call hwmon_notify_event (with a notifier) on WMI fan speed events
> 
> v8:
>   - Fix coding style issues
>   - Use MILLIDEGREE_PER_DEGREE instead of MILLI to define the temperature unit more precisely.
>   - Align lines with the first occurrence of HWMON
>   - Remove the unnecessary empty line in error handling
>   - Reverse the logic of kb_mode_strings and drop the mode_str variable
> 
> v7:
>   - Remove the unused includes (asm/)
>   - Align values with tab
>   - remove the previous test code which i forgot to remove
>   - return values directly with the "return" statement
>   - remove the wrong comment "Full-speed" since I've already use the value
>     "WMI_PP_FULL_SPEED" in the switch case
>   - remove the empty lines
>   - Change the two variables (val, ret) to reverse xmas-tree order.
>   - Add missing includes and sort them in the alphabetical order.
>   - use endianness types and conversion functions to parse temperature in
>     the wmi response
> 
> v6:
>   - add base commit
> 
> v5:
>   - add fallthrough on the PLATFORM_PROFILE_BALANCED_PERFORMANCE switch
>     case
> 
> v4:
>   - check the DC power state before switching to performance/full-speed mode
> 
> v3:
>   - Fix email address mismatch in Signed-off-by and From headers.
>   - implement the WMI event handler
>   - code style improvements
>   - condition on the performance platform profile switch
>   - driver documentation
> 
> v2:
>   - Add PLATFORM_PROFILE_BALANCED_PERFORMANCE platform profile support
> 
>  .../wmi/devices/bitland-mifs-wmi.rst          | 207 +++++
>  drivers/platform/x86/Kconfig                  |  18 +
>  drivers/platform/x86/Makefile                 |   1 +
>  drivers/platform/x86/bitland-mifs-wmi.c       | 846 ++++++++++++++++++
>  4 files changed, 1072 insertions(+)
>  create mode 100644 Documentation/wmi/devices/bitland-mifs-wmi.rst
>  create mode 100644 drivers/platform/x86/bitland-mifs-wmi.c
> 
> diff --git a/Documentation/wmi/devices/bitland-mifs-wmi.rst b/Documentation/wmi/devices/bitland-mifs-wmi.rst
> new file mode 100644
> index 000000000000..9e86ecc2993c
> --- /dev/null
> +++ b/Documentation/wmi/devices/bitland-mifs-wmi.rst
> @@ -0,0 +1,207 @@
> +.. 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.
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 4cb7d97a9fcc..2ffa4ecf65b0 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -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
> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
> index d25762f7114f..872ac3842391 100644
> --- a/drivers/platform/x86/Makefile
> +++ b/drivers/platform/x86/Makefile
> @@ -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
> diff --git a/drivers/platform/x86/bitland-mifs-wmi.c b/drivers/platform/x86/bitland-mifs-wmi.c
> new file mode 100644
> index 000000000000..1a50a6df99a9
> --- /dev/null
> +++ b/drivers/platform/x86/bitland-mifs-wmi.c
> @@ -0,0 +1,846 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Linux driver for Bitland notebooks.
> + *
> + * Copyright (C) 2026 2 Mingyou Chen <qby140326@gmail.com>
> + */
> +
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +
> +#include <linux/acpi.h>
> +#include <linux/array_size.h>
> +#include <linux/bits.h>
> +#include <linux/cleanup.h>
> +#include <linux/container_of.h>
> +#include <linux/dev_printk.h>
> +#include <linux/device.h>
> +#include <linux/device/devres.h>
> +#include <linux/err.h>
> +#include <linux/hwmon.h>
> +#include <linux/init.h>
> +#include <linux/input-event-codes.h>
> +#include <linux/input.h>
> +#include <linux/input/sparse-keymap.h>
> +#include <linux/kernel.h>
> +#include <linux/leds.h>
> +#include <linux/module.h>
> +#include <linux/notifier.h>
> +#include <linux/platform_profile.h>
> +#include <linux/pm.h>
> +#include <linux/power_supply.h>
> +#include <linux/stddef.h>
> +#include <linux/string.h>
> +#include <linux/sysfs.h>
> +#include <linux/unaligned.h>
> +#include <linux/units.h>
> +#include <linux/wmi.h>
> +
> +#define DRV_NAME		"bitland-mifs-wmi"
> +#define BITLAND_MIFS_GUID	"B60BFB48-3E5B-49E4-A0E9-8CFFE1B3434B"
> +#define BITLAND_EVENT_GUID	"46C93E13-EE9B-4262-8488-563BCA757FEF"
> +
> +enum bitland_mifs_operation {
> +	WMI_METHOD_GET	= 250,
> +	WMI_METHOD_SET	= 251,
> +};
> +
> +enum bitland_mifs_function {
> +	WMI_FN_SYSTEM_PER_MODE		= 8,
> +	WMI_FN_GPU_MODE			= 9,
> +	WMI_FN_KBD_TYPE			= 10,
> +	WMI_FN_FN_LOCK			= 11,
> +	WMI_FN_TP_LOCK			= 12,
> +	WMI_FN_FAN_SPEEDS		= 13,
> +	WMI_FN_RGB_KB_MODE		= 16,
> +	WMI_FN_RGB_KB_COLOR		= 17,
> +	WMI_FN_RGB_KB_BRIGHTNESS	= 18,
> +	WMI_FN_SYSTEM_AC_TYPE		= 19,
> +	WMI_FN_MAX_FAN_SWITCH		= 20,
> +	WMI_FN_MAX_FAN_SPEED		= 21,
> +	WMI_FN_CPU_THERMOMETER		= 22,
> +	WMI_FN_CPU_POWER		= 23,
> +};
> +
> +enum bitland_system_ac_mode {
> +	WMI_SYSTEM_AC_TYPEC		= 1,
> +	/* Unknown type, this is unused in the original driver */
> +	WMI_SYSTEM_AC_CIRCULARHOLE	= 2,
> +};
> +
> +enum bitland_mifs_power_profile {
> +	WMI_PP_BALANCED		= 0,
> +	WMI_PP_PERFORMANCE	= 1,
> +	WMI_PP_QUIET		= 2,
> +	WMI_PP_FULL_SPEED	= 3,
> +};
> +
> +enum bitland_mifs_event_id {
> +	WMI_EVENT_RESERVED_1		= 1,
> +	WMI_EVENT_RESERVED_2		= 2,
> +	WMI_EVENT_RESERVED_3		= 3,
> +	WMI_EVENT_AIRPLANE_MODE		= 4,
> +	WMI_EVENT_KBD_BRIGHTNESS	= 5,
> +	WMI_EVENT_TOUCHPAD_STATE	= 6,
> +	WMI_EVENT_FNLOCK_STATE		= 7,
> +	WMI_EVENT_KBD_MODE		= 8,
> +	WMI_EVENT_CAPSLOCK_STATE	= 9,
> +	WMI_EVENT_CALCULATOR_START	= 11,
> +	WMI_EVENT_BROWSER_START		= 12,
> +	WMI_EVENT_NUMLOCK_STATE		= 13,
> +	WMI_EVENT_SCROLLLOCK_STATE	= 14,
> +	WMI_EVENT_PERFORMANCE_PLAN	= 15,
> +	WMI_EVENT_FN_J			= 16,
> +	WMI_EVENT_FN_F			= 17,
> +	WMI_EVENT_FN_0			= 18,
> +	WMI_EVENT_FN_1			= 19,
> +	WMI_EVENT_FN_2			= 20,
> +	WMI_EVENT_FN_3			= 21,
> +	WMI_EVENT_FN_4			= 22,
> +	WMI_EVENT_FN_5			= 24,
> +	WMI_EVENT_REFRESH_RATE		= 25,
> +	WMI_EVENT_CPU_FAN_SPEED		= 26,
> +	WMI_EVENT_GPU_FAN_SPEED		= 32,
> +	WMI_EVENT_WIN_KEY_LOCK		= 33,
> +	WMI_EVENT_RESERVED_23		= 34,
> +	WMI_EVENT_OPEN_APP		= 35,
> +};
> +
> +enum bitland_mifs_event_type {
> +	WMI_EVENT_TYPE_HOTKEY	= 1,
> +};
> +
> +enum bitland_wmi_device_type {
> +	BITLAND_WMI_CONTROL	= 0,
> +	BITLAND_WMI_EVENT	= 1,
> +};
> +
> +struct bitland_mifs_input {
> +	u8 reserved1;
> +	u8 operation;
> +	u8 reserved2;
> +	u8 function;
> +	u8 payload[28];
> +} __packed;
> +
> +struct bitland_mifs_output {
> +	u8 reserved1;
> +	u8 operation;
> +	u8 reserved2;
> +	u8 function;
> +	u8 data[28];
> +} __packed;
> +
> +struct bitland_mifs_event {
> +	u8 event_type;
> +	u8 event_id;
> +	u8 value_low;	/* For most events, this is the value */
> +	u8 value_high;	/* For fan speed events, combined with value_low */
> +	u8 reserved[4];
> +} __packed;
> +
> +static BLOCKING_NOTIFIER_HEAD(bitland_notifier_list);
> +
> +enum bitland_notifier_actions {
> +	BITLAND_NOTIFY_KBD_BRIGHTNESS,
> +	BITLAND_NOTIFY_PLATFORM_PROFILE,
> +	BITLAND_NOTIFY_HWMON,
> +};
> +
> +struct bitland_fan_notify_data {
> +	int channel; /* 0 = CPU, 1 = GPU */
> +	u16 speed;
> +};
> +
> +struct bitland_mifs_wmi_data {
> +	struct wmi_device *wdev;
> +	struct mutex lock;		/* Protects WMI calls */
> +	struct led_classdev kbd_led;
> +	struct notifier_block notifier;
> +	struct input_dev *input_dev;
> +	struct device *hwmon_dev;
> +	struct device *pp_dev;
> +	enum platform_profile_option saved_profile;
> +};
> +
> +static int bitland_mifs_wmi_call(struct bitland_mifs_wmi_data *data,
> +				 const struct bitland_mifs_input *input,
> +				 struct bitland_mifs_output *output)
> +{
> +	struct wmi_buffer in_buf = { .length = sizeof(*input), .data = (void *)input };
> +	struct wmi_buffer out_buf = { 0 };
> +	int ret;
> +
> +	void *out_data __free(kfree) = NULL;
> +
> +	guard(mutex)(&data->lock);
> +
> +	ret = wmidev_invoke_method(data->wdev, 0, 1, &in_buf, output ? &out_buf : NULL);
> +	if (ret)
> +		return ret;
> +
> +	if (output) {
> +		out_data = out_buf.data;

Don't add separate = NULL line above at all as explained in the long 
comment in cleanup.h, just put:

		void *out_data __free(kfree) = out_buf.data;

...here directly.

> +		if (out_buf.length < sizeof(*output))
> +			return -EIO;
> +
> +		memcpy(output, out_data, sizeof(*output));
> +	}
> +
> +	return 0;
> +}
> +
> +static int laptop_profile_get(struct device *dev,
> +			      enum platform_profile_option *profile)
> +{
> +	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);
> +	struct bitland_mifs_input input = {
> +		.reserved1 = 0,
> +		.operation = WMI_METHOD_GET,
> +		.reserved2 = 0,
> +		.function = WMI_FN_SYSTEM_PER_MODE,
> +	};
> +	struct bitland_mifs_output result;
> +	int ret;
> +
> +	ret = bitland_mifs_wmi_call(data, &input, &result);
> +	if (ret)
> +		return ret;
> +
> +	switch (result.data[0]) {
> +	case WMI_PP_BALANCED:
> +		*profile = PLATFORM_PROFILE_BALANCED;
> +		break;
> +	case WMI_PP_PERFORMANCE:
> +		*profile = PLATFORM_PROFILE_BALANCED_PERFORMANCE;
> +		break;
> +	case WMI_PP_QUIET:
> +		*profile = PLATFORM_PROFILE_LOW_POWER;
> +		break;
> +	case WMI_PP_FULL_SPEED:
> +		*profile = PLATFORM_PROFILE_PERFORMANCE;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int bitland_check_performance_capability(struct bitland_mifs_wmi_data *data)
> +{
> +	struct bitland_mifs_input input = {
> +		.operation = WMI_METHOD_GET,
> +		.function = WMI_FN_SYSTEM_AC_TYPE,
> +	};
> +	struct bitland_mifs_output output;
> +	int ret;
> +
> +	/* Full-speed/performance mode requires DC power (not USB-C) */
> +	if (!power_supply_is_system_supplied())
> +		return -EOPNOTSUPP;
> +
> +	ret = bitland_mifs_wmi_call(data, &input, &output);
> +	if (ret)
> +		return ret;
> +
> +	if (output.data[0] != WMI_SYSTEM_AC_CIRCULARHOLE)
> +		return -EOPNOTSUPP;
> +
> +	return 0;
> +}
> +
> +static int laptop_profile_set(struct device *dev,
> +			      enum platform_profile_option profile)
> +{
> +	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);
> +	struct bitland_mifs_input input = {
> +		.reserved1 = 0,
> +		.operation = WMI_METHOD_SET,
> +		.reserved2 = 0,
> +		.function = WMI_FN_SYSTEM_PER_MODE,
> +	};
> +	int ret;
> +	u8 val;
> +
> +	switch (profile) {
> +	case PLATFORM_PROFILE_LOW_POWER:
> +		val = WMI_PP_QUIET;
> +		break;
> +	case PLATFORM_PROFILE_BALANCED:
> +		val = WMI_PP_BALANCED;
> +		break;
> +	case PLATFORM_PROFILE_BALANCED_PERFORMANCE:
> +		ret = bitland_check_performance_capability(data);
> +		if (ret)
> +			return ret;
> +		val = WMI_PP_PERFORMANCE;
> +		break;
> +	case PLATFORM_PROFILE_PERFORMANCE:
> +		ret = bitland_check_performance_capability(data);
> +		if (ret)
> +			return ret;
> +		val = WMI_PP_FULL_SPEED;
> +		break;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +
> +	input.payload[0] = val;
> +
> +	return bitland_mifs_wmi_call(data, &input, NULL);
> +}
> +
> +static int platform_profile_probe(void *drvdata, unsigned long *choices)
> +{
> +	set_bit(PLATFORM_PROFILE_LOW_POWER, choices);
> +	set_bit(PLATFORM_PROFILE_BALANCED, choices);
> +	set_bit(PLATFORM_PROFILE_BALANCED_PERFORMANCE, choices);
> +	set_bit(PLATFORM_PROFILE_PERFORMANCE, choices);
> +
> +	return 0;
> +}
> +
> +static int bitland_mifs_wmi_suspend(struct device *dev)
> +{
> +	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);
> +	enum platform_profile_option profile;
> +	int ret;
> +
> +	ret = laptop_profile_get(data->pp_dev, &profile);
> +	if (ret == 0)
> +		data->saved_profile = profile;
> +
> +	return ret;
> +}
> +
> +static int bitland_mifs_wmi_resume(struct device *dev)
> +{
> +	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);
> +
> +	dev_dbg(dev, "Resuming, restoring profile %d\n", data->saved_profile);
> +	return laptop_profile_set(dev, data->saved_profile);
> +}
> +
> +static DEFINE_SIMPLE_DEV_PM_OPS(bitland_mifs_wmi_pm_ops,
> +				bitland_mifs_wmi_suspend,
> +				bitland_mifs_wmi_resume);
> +
> +static const struct platform_profile_ops laptop_profile_ops = {
> +	.probe = platform_profile_probe,
> +	.profile_get = laptop_profile_get,
> +	.profile_set = laptop_profile_set,
> +};
> +
> +static const char *const fan_labels[] = {
> +	"CPU", /* 0 */
> +	"GPU", /* 1 */
> +	"SYS", /* 2 */
> +};
> +
> +static int laptop_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
> +			     u32 attr, int channel, long *val)
> +{
> +	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);
> +	struct bitland_mifs_input input = {
> +		.reserved1 = 0,
> +		.operation = WMI_METHOD_GET,
> +		.reserved2 = 0,
> +	};
> +	struct bitland_mifs_output res;
> +	int ret;
> +
> +	switch (type) {
> +	case hwmon_temp:
> +		input.function = WMI_FN_CPU_THERMOMETER;
> +		ret = bitland_mifs_wmi_call(data, &input, &res);
> +		if (!ret)
> +			*val = res.data[0] * MILLIDEGREE_PER_DEGREE;
> +		return ret;
> +	case hwmon_fan:
> +		input.function = WMI_FN_FAN_SPEEDS;
> +		ret = bitland_mifs_wmi_call(data, &input, &res);
> +		if (ret)
> +			return ret;
> +
> +		switch (channel) {
> +		case 0: /* CPU */
> +			*val = get_unaligned_le16(&res.data[0]);
> +			return 0;
> +		case 1: /* GPU */
> +			*val = get_unaligned_le16(&res.data[2]);
> +			return 0;
> +		case 2: /* SYS */
> +			*val = get_unaligned_le16(&res.data[6]);
> +			return 0;
> +		default:
> +			return -EINVAL;
> +		}
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static int laptop_hwmon_read_string(struct device *dev,
> +				    enum hwmon_sensor_types type, u32 attr,
> +				    int channel, const char **str)
> +{
> +	if (type == hwmon_fan && attr == hwmon_fan_label) {
> +		if (channel >= 0 && channel < ARRAY_SIZE(fan_labels)) {
> +			*str = fan_labels[channel];
> +			return 0;
> +		}
> +	}
> +	return -EINVAL;
> +}
> +
> +static const struct hwmon_channel_info *laptop_hwmon_info[] = {
> +	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
> +	HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_LABEL,
> +				HWMON_F_INPUT | HWMON_F_LABEL,
> +				HWMON_F_INPUT | HWMON_F_LABEL),
> +	NULL
> +};
> +
> +static const struct hwmon_ops laptop_hwmon_ops = {
> +	.visible = 0444,
> +	.read = laptop_hwmon_read,
> +	.read_string = laptop_hwmon_read_string,
> +};
> +
> +static const struct hwmon_chip_info laptop_chip_info = {
> +	.ops = &laptop_hwmon_ops,
> +	.info = laptop_hwmon_info,
> +};
> +
> +static int laptop_kbd_led_set(struct led_classdev *led_cdev,
> +			      enum led_brightness value)
> +{
> +	struct bitland_mifs_wmi_data *data =
> +		container_of(led_cdev, struct bitland_mifs_wmi_data, kbd_led);
> +	struct bitland_mifs_input input = {
> +		.reserved1 = 0,
> +		.operation = WMI_METHOD_SET,
> +		.reserved2 = 0,
> +		.function = WMI_FN_RGB_KB_BRIGHTNESS,
> +	};
> +
> +	input.payload[0] = (u8)value;
> +
> +	return bitland_mifs_wmi_call(data, &input, NULL);
> +}
> +
> +static enum led_brightness laptop_kbd_led_get(struct led_classdev *led_cdev)
> +{
> +	struct bitland_mifs_wmi_data *data =
> +		container_of(led_cdev, struct bitland_mifs_wmi_data, kbd_led);
> +	struct bitland_mifs_input input = {
> +		.reserved1 = 0,
> +		.operation = WMI_METHOD_GET,
> +		.reserved2 = 0,
> +		.function = WMI_FN_RGB_KB_BRIGHTNESS,
> +	};
> +	struct bitland_mifs_output res;
> +	int ret;
> +
> +	ret = bitland_mifs_wmi_call(data, &input, &res);
> +	if (ret)
> +		return ret;
> +
> +	return res.data[0];
> +}
> +
> +static const char *const gpu_mode_strings[] = {
> +	"hybrid",
> +	"discrete",
> +	"uma",
> +};
> +
> +/* GPU Mode: 0:Hybrid, 1:Discrete, 2:UMA */
> +static ssize_t gpu_mode_show(struct device *dev, struct device_attribute *attr,
> +			     char *buf)
> +{
> +	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);
> +	struct bitland_mifs_input input = {
> +		.reserved1 = 0,
> +		.operation = WMI_METHOD_GET,
> +		.reserved2 = 0,
> +		.function = WMI_FN_GPU_MODE,
> +	};
> +	struct bitland_mifs_output res;
> +	u8 mode_val;
> +	int ret;
> +
> +	ret = bitland_mifs_wmi_call(data, &input, &res);
> +	if (ret)
> +		return ret;
> +
> +	mode_val = res.data[0];
> +	if (mode_val >= ARRAY_SIZE(gpu_mode_strings))
> +		return -EPROTO;
> +
> +	return sysfs_emit(buf, "%s\n", gpu_mode_strings[mode_val]);
> +}
> +
> +static ssize_t gpu_mode_store(struct device *dev, struct device_attribute *attr,
> +			      const char *buf, size_t count)
> +{
> +	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);
> +	struct bitland_mifs_input input = {
> +		.reserved1 = 0,
> +		.operation = WMI_METHOD_SET,
> +		.reserved2 = 0,
> +		.function = WMI_FN_GPU_MODE,
> +	};
> +	int val;
> +	int ret;
> +
> +	val = sysfs_match_string(gpu_mode_strings, buf);
> +	if (val < 0)
> +		return -EINVAL;
> +
> +	input.payload[0] = (u8)val;
> +
> +	ret = bitland_mifs_wmi_call(data, &input, NULL);
> +	if (ret)
> +		return ret;
> +
> +	return count;
> +}
> +
> +static const char *const kb_mode_strings[] = {
> +	"off",		/* 0 */
> +	"cyclic",	/* 1 */
> +	"fixed",	/* 2 */
> +	"custom",	/* 3 */
> +};
> +
> +static ssize_t kb_mode_show(struct device *dev, struct device_attribute *attr,
> +			    char *buf)
> +{
> +	int ret;
> +	u8 mode_val;
> +	struct bitland_mifs_output res;
> +	struct bitland_mifs_input input = {
> +		.reserved1 = 0,
> +		.operation = WMI_METHOD_GET,
> +		.reserved2 = 0,
> +		.function = WMI_FN_RGB_KB_MODE,
> +	};
> +	struct bitland_mifs_wmi_data *data = dev_get_drvdata(dev);

Reverse xmas tree order has the "tree" upside down so the shorter lines 
should be at the bottom.

Thanks.

-- 
 i.