Intel Raptor Lake Thunderbolt, CL1 Low-Power State Coming With Linux 6.0

Greg Kroah-Hartman has submitted all of the USB and Thunderbolt driver changes targeting the Linux 6.0 kernel of which there is a lot of new hardware enablement and enhancements to existing driver support.

First up, with Linux 6.0 there is now Thunderbolt support for upcoming Intel Raptor Lake platforms. Raptor lake as the successor to Alder Lake is due out later this year and recent Linux kernels have seen a lot of bring-up work for these 13th Gen Core processors. There has been work on the Raptor Lake graphics support and other new device IDs added to other drivers for preparing this evolutionary successor to Alder Lake. With the USB/Thunderbolt pull, Raptor Lake Thunderbolt is set to work on Linux 6.0.

Also new with Linux 6.0 is CL1 support for USB4 and Intel Titan Ridge controllers. CLx is for link low-power states to reduce transmitter and receiver power when a lane is idle. Last year Intel added CLx/CL0 support for USB4 devices and their Titan Ridge controller. With Linux 6.0 they are adding CL1 support for USB4 devices and Titan Ridge. CL1 is a second low-power state of the link and is used for reducing transmitter and receiver power when a high-speed lane is idle. Both sides of the link need to support CL1 for it to be used for enhancing thermal/power management.

Other USB changes in Linux 6.0 include Target Peripheral List (TPL) support for identifying targeted devices during embedded host compliance testing with the DWC2 driver, moving the octeon-usb driver out of staging, expanded speed reporting with the "testusb" tool code, support for the PolarFire SoC's MUSB controller, various USB Type-C driver improvements, ACPI-based I2c client enumeration for AMD ASICs with the UCSI_CCG driver, and other fixes/enhancements.

The full list of USB and Thunderbolt feature patches for Linux 6.0 can be found via this pull request with that eight thousand lines of new code already merged to Linux Git.