Pull initial i3c support from Boris Brezillon:
 "Add initial support for I3C along with two I3C master controller
  drivers"

* tag 'i3c/for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux:
  i3c: master: cdns: fix I2C transfers in Cadence I3C master driver
  ic3: off by one in mode_show()
  i3c: fix an error code in i3c_master_add_i3c_dev_locked()
  i3c: master: dw: fix mask operation by using the correct operator
  MAINTAINERS: Add myself as the dw-i3c-master module maintainer
  dt-binding: i3c: Document Synopsys DesignWare I3C
  i3c: master: Add driver for Synopsys DesignWare IP
  i3c: master: Remove set but not used variable 'old_i3c_scl_lim'
  dt-bindings: i3c: Document Cadence I3C master bindings
  i3c: master: Add driver for Cadence IP
  MAINTAINERS: Add myself as the I3C subsystem maintainer
  dt-bindings: i3c: Document core bindings
  i3c: Add sysfs ABI spec
  docs: driver-api: Add I3C documentation
  i3c: Add core I3C infrastructure