This second batch of input updates for ending the Linux 4.5 kernel merge window are mainly for improving the Xbox One controller support. Some of the work includes removing spurious events for the wireless Xbox 360 controller, using the LED API for identifying the XPad wireless controllers, correctly handling concurrent LED/FF requests, correcting the XBox One pad device name, handling present/gone correctly within the driver, and updating the XBox One Force Feedback support.
Some of this XPad/Xbox driver work for Linux 4.5 was once again submitted by Valve. The force feedback work was one of the patches by Valve's Pierre-Loup A. Griffais and he explained, "There's apparently a serial number woven into both input and output packets; neglecting to specify a valid serial number causes the controller to ignore the rumble packets. The scale of the rumble was also apparently halved in the packets. The initialization packet had to be changed to allow force feedback to work."
More details via this pull request.