Pull tty and serial driver updates from Greg KH:
 "Here is the big set of tty and serial driver updates for 5.13-rc1.

  Actually busy this release, with a number of cleanups happening:

   - much needed core tty cleanups by Jiri Slaby

   - removal of unused and orphaned old-style serial drivers. If anyone
     shows up with this hardware, it is trivial to restore these but we
     really do not think they are in use anymore.

   - fixes and cleanups from Johan Hovold on a number of termios setting
     corner cases that loads of drivers got wrong as well as removing
     unneeded code due to tty core changes from long ago that were never
     propagated out to the drivers

   - loads of platform-specific serial port driver updates and fixes

   - coding style cleanups and other small fixes and updates all over
     the tty/serial tree.

  All of these have been in linux-next for a while now with no reported
  issues"

* tag 'tty-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (186 commits)
  serial: extend compile-test coverage
  serial: stm32: add FIFO threshold configuration
  dt-bindings: serial: 8250: update TX FIFO trigger level
  dt-bindings: serial: stm32: override FIFO threshold properties
  dt-bindings: serial: add RX and TX FIFO properties
  serial: xilinx_uartps: drop low-latency workaround
  serial: vt8500: drop low-latency workaround
  serial: timbuart: drop low-latency workaround
  serial: sunsu: drop low-latency workaround
  serial: sifive: drop low-latency workaround
  serial: txx9: drop low-latency workaround
  serial: sa1100: drop low-latency workaround
  serial: rp2: drop low-latency workaround
  serial: rda: drop low-latency workaround
  serial: owl: drop low-latency workaround
  serial: msm_serial: drop low-latency workaround
  serial: mpc52xx_uart: drop low-latency workaround
  serial: meson: drop low-latency workaround
  serial: mcf: drop low-latency workaround
  serial: lpc32xx_hs: drop low-latency workaround
  ...