The I3C Subsystem Seeks To Be Included In Linux 4.21

The I3C subsystem had sought to be included in Linux 4.20, but ultimately it was rejected for being too late in the cycle for introducing a brand new subsystem. But now it's requested to be pulled into the upcoming Linux 4.21 merge window.

Boris Brezillon has issued a new pull request looking to add I3C to the Linux 4.21 kernel. That 4.21 merge window should open next week, but due to the holidays, a number of PRs have been submitted early -- including the I3C Material.

This pull adds in the I3C core infrastructure, documents the ABI, and the initial I3C user is the Synopsys DesignWire driver.

I3C is a sensor interface specification from MIPI introduced in 2017 as a combination of the best aspects of I2C and SPI specifications while making the standard suitable for IoT devices.