USB Type-C Port Manager Promoted Out Of Staging For Linux 4.15

The USB Type-C port manager that originally premiered in Linux 4.12 will be promoted out of staging with the Linux 4.15 kernel.

Greg Kroah-Hartman sent in the pull requests today for the various kernel subsystems he maintains. With the USB updates alongside various small updates throughout the subsystem, the Type-C manager code was promoted out of staging.

Guenter Roeck proposed the change some weeks back with this TCPM Type-C Port Manager code being ready to move out of staging. The TCPM code provides a USB power delivery and state machine for Type-C port controllers with both source and sink port support -- basically the TCPM code manages each port's role with this newer USB standard.

Lower-level Linux USB controller drivers make use of this TCPM state machine and then use it for setting the current limit, power delivery messaging, activating/deactivating various features, etc.

Meanwhile, the staging pull for Linux 4.15 comes with a variety of clean-ups and other smaller changes to the existing drivers/functionality within this area of the Linux kernel but no notable driver additions this cycle.