serial: imx: Only wakeup via RTSDEN bit if the system has RTS/CTS
The wakeup mechanism via RTSDEN bit relies on the system using the RTS/CTS
lines, so only allow such wakeup method when the system actually has
RTS/CTS support.
Fixes: bc85734b126f ("serial: imx: allow waking up on RTSD")
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Martin Kaiser <martin@kaiser.cx>
Acked-by: Fugang Duan <fugang.duan@nxp.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index c2b29fd..7143da3 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -2225,12 +2225,14 @@ static void serial_imx_enable_wakeup(struct imx_port *sport, bool on)
val &= ~UCR3_AWAKEN;
writel(val, sport->port.membase + UCR3);
- val = readl(sport->port.membase + UCR1);
- if (on)
- val |= UCR1_RTSDEN;
- else
- val &= ~UCR1_RTSDEN;
- writel(val, sport->port.membase + UCR1);
+ if (sport->have_rtscts) {
+ val = readl(sport->port.membase + UCR1);
+ if (on)
+ val |= UCR1_RTSDEN;
+ else
+ val &= ~UCR1_RTSDEN;
+ writel(val, sport->port.membase + UCR1);
+ }
}
static int imx_serial_port_suspend_noirq(struct device *dev)