tty: Add software emulated RS485 support for 8250
Implementation of software emulation of RS485 direction handling is based on omap_serial driver. Before and after transmission RTS is set to the appropriate value. Note that before calling serial8250_em485_init() the caller has to ensure that UART will interrupt when shift register empty. Otherwise, emultaion cannot be used. Both serial8250_em485_init() and serial8250_em485_destroy() are idempotent functions. Signed-off-by: NMatwey V. Kornilov <matwey@sai.msu.ru> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Showing
想要评论请 注册 或 登录