The early return from serial8250_start_tx() added by commit e490c9144cfa ("tty: Add software emulated RS485 support for 8250") failed to call serial8250_rpm_put_tx() that normally gets called on __stop_tx(). Likely this is a harmless issue as the RS485 using folks probably are not using runtime PM for the serial ports. Fixes: e490c9144cfa ("tty: Add software emulated RS485 support for 8250") Cc: Matwey V. Kornilov <matwey@xxxxxxxxxx> Cc: Steffen Trumtrar <s.trumtrar@xxxxxxxxxxxxxx> Cc: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> --- drivers/tty/serial/8250/8250_port.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -1681,8 +1681,10 @@ static void serial8250_start_tx(struct uart_port *port) return; if (em485 && - em485->active_timer == &em485->start_tx_timer) + em485->active_timer == &em485->start_tx_timer) { + serial8250_rpm_put_tx(up); return; + } if (em485) start_tx_rs485(port); -- 2.35.1