It's been 14 years already since Microsoft announced the Surface RT hybrid tablet as their first-generation Surface device for going up against the Apple iPad. All these years later, this NVIDIA Tegra 3 powered device is finally seeing a mainline Linux kernel driver for supporting battery and charger status.

In the event you still have a Microsoft Surface RT or manage to snag one for a good deal used, the Linux 7.2 kernel is introducing the "surface-rt-ec" driver for interfacing with the Embedded Controller (EC) of this first-generation Microsoft Surface device. Enabled via the BATTERY_CHARGER_SURFACE_RT Kconfig switch, this exposes the battery properties and charger status under Linux. Open-source developer Jonas Schwöbel created this driver.

This exposes properties such as the current charge level, the power current, manufacturer / model information, serial number, current voltage, and whether the charger is active. This driver was previously available as an out-of-tree kernel module while is being mainlined with Linux 7.2. While now in the mainline kernel, the Surface RT would be difficult to use for much in the way of any modern tasks these days with this Tegra 3 device having just 2GB of RAM.

This Microsoft Surface RT EC driver is the main headline of the power supply merge for Linux 7.2.