| Message ID | 20220411094805.45696-2-tony@atomide.com |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
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 @@ -1677,8 +1677,10 @@ static void serial8250_start_tx(struct uart_port *port) serial8250_rpm_get_tx(up); - if (!port->x_char && uart_circ_empty(&port->state->xmit)) + if (!port->x_char && uart_circ_empty(&port->state->xmit)) { + serial8250_rpm_put_tx(up); return; + } if (em485 && em485->active_timer == &em485->start_tx_timer) {
Commit 932d596378b0 ("serial: 8250: Return early in .start_tx() if there are no chars to send") caused a regression where the drivers implementing runtime PM stopped idling. We need to call serial8250_rpm_put_tx() on early exit, it normally gets called later on at __stop_tx(). Fixes: 932d596378b0 ("serial: 8250: Return early in .start_tx() if there are no chars to send") Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Tony Lindgren <tony@atomide.com> --- drivers/tty/serial/8250/8250_port.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)