AC Adapter

modulename: ac.ko
configname: CONFIG_ACPI_AC

Linux Kernel Configuration
└─> Power management and ACPI options
└─> ACPI (Advanced Configuration and Power Interface) Support
└─> AC Adapter

This driver supports the AC Adapter object, which indicates
whether a system is on AC or not. If you have a system that can
switch between A/C and battery, say Y.

To compile this driver as a module, choose M here:
the module will be called ac.

source code: