Some boards are wired so that they support both rs232 and rs485, with a gpio controlling a mux connecting the SOC's pins to the appropriate external circuitry. Instead of requiring the application to know about such details and handle the gpio appropriately, allow it to be described in device tree and let the serial core code handle it if present. Tested on a board based on imx8mp. Rasmus Villemoes (2): dt-bindings: serial: rs485: add rs485-mux-gpios binding serial: core: implement support for rs485-mux-gpios .../devicetree/bindings/serial/rs485.yaml | 5 +++ drivers/tty/serial/serial_core.c | 35 +++++++++++++++++-- include/linux/serial_core.h | 1 + 3 files changed, 39 insertions(+), 2 deletions(-) -- 2.40.1.1.g1c60b9335d
