The New ACPI TAD Driver & CPUFreq Improvements Ready For Linux 4.17 Kernel

Written by Michael Larabel in Hardware on 2 April 2018 at 10:01 AM EDT. Add A Comment
Rafael Wysocki of Intel has already submitted the power management and ACPI updates for the newly-opened Linux 4.17 kernel merge window.

Arguably most interesting about the PM/ACPI changes this cycle is the new ACPI Time and Alarm driver for Linux. For systems supporting this ACPI specification, users can manage wake-up timers of the Time and Alarm Device with setting new timers for system wake-up and modifying existing timers, all via sysfs. TAD information spans reboots and power states and is much more featureful than the basic real-time clock wake-up function you might find within your BIOS.

Besides this new ACPI TAD driver, the power management code provides Cannonlake support for the Intel RAPL power-capping drive, device link handling improvements, CPUFreq clean-ups, the ACPI battery driver now supports battery thresholds for Lenovo ThinkPads, and various other updates.

The complete list of changes can be found via the power management queue and ACPI pull.
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