diff mbox series

[v6,1/3] serial: imx: set_termios(): do not enable autoRTS if RTS is unset

Message ID 1563823331-5629-2-git-send-email-sorganov@gmail.com (mailing list archive)
State Mainlined
Commit a25aee902e666e8cc41e33754f13c69a979dd67f
Headers show
Series serial: imx: fix RTS and RTS/CTS handling | expand

Commit Message

Sergey Organov July 22, 2019, 7:22 p.m. UTC 
Don't let receiver hardware automatically control RTS output if it
was requested to be inactive.

To ensure this, set_termios() shouldn't set UCR2_CTSC bit if UCR2_CTS
(=TIOCM_RTS) is cleared. Added corresponding check in imx_uart_rts_auto()
to fix this.

Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Sergey Organov <sorganov@gmail.com>
---
 drivers/tty/serial/imx.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 57d6e6b..32f36d8 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -405,7 +405,12 @@  static void imx_uart_rts_inactive(struct imx_port *sport, u32 *ucr2)
 /* called with port.lock taken and irqs caller dependent */
 static void imx_uart_rts_auto(struct imx_port *sport, u32 *ucr2)
 {
-	*ucr2 |= UCR2_CTSC;
+	/*
+	 * Only let receiver control RTS output if we were not requested to have
+	 * RTS inactive (which then should take precedence).
+	 */
+	if (*ucr2 & UCR2_CTS)
+		*ucr2 |= UCR2_CTSC;
 }
 
 /* called with port.lock taken and irqs off */