Microsoft Surface System Aggregator Module Subsystem and Drivers

modulename: surface_aggregator.ko

configname: CONFIG_SURFACE_AGGREGATOR

Linux Kernel Configuration
└─>Device Drivers
└─>Microsoft Surface Platform-Specific Device Drivers
└─>Serial device bus
└─>Microsoft Surface System Aggregator Module Subsystem and Drivers
In linux kernel since version 4.14.326 (release Date: 2023-09-23)  
The Surface System Aggregator Module (Surface SAM or SSAM) is an
embedded controller (EC) found on 5th- and later-generation Microsoft
Surface devices (i.e. Surface Pro 5, Surface Book 2, Surface Laptop,
and newer, with exception of Surface Go series devices).

Depending on the device in question, this EC provides varying
functionality, including:
- EC access from ACPI via Surface ACPI Notify (5th- and 6th-generation)
- battery status information (all devices)
- thermal sensor access (all devices)
- performance mode / cooling mode control (all devices)
- clipboard detachment system control (Surface Book 2 and 3)
- HID / keyboard input (Surface Laptops, Surface Book 3)

This option controls whether the Surface SAM subsystem core will be
built. This includes a driver for the Surface Serial Hub (SSH), which
is the device responsible for the communication with the EC, and a
basic kernel interface exposing the EC functionality to other client
drivers, i.e. allowing them to make requests to the EC and receive
events from it. Selecting this option alone will not provide any
client drivers and therefore no functionality beyond the in-kernel
interface. Said functionality is the responsibility of the respective
client drivers.

Note: While 4th-generation Surface devices also make use of a SAM EC,
due to a difference in the communication interface of the controller,
only 5th and later generations are currently supported. Specifically,
devices using SAM-over-SSH are supported, whereas devices using
SAM-over-HID, which is used on the 4th generation, are currently not
supported.

Choose m if you want to build the SAM subsystem core and SSH driver as
module, y if you want to build it into the kernel and n if you don't
want it at all.

source code: