Documentation/serial/driver clearly states:

    If the port does not support CTS, DCD or DSR, the driver should
    indicate that the signal is permanently active.

Hence always set TIOCM_CTS, as we currently don't look at the CTS
hardware line state at all.

FWIW, this fixes the transmit path when hardware-assisted flow control
is enabled, and userspace enables CRTSCTS.
The receive path is still broken, as RTS is never asserted.

Signed-off-by: Geert Uytterhoeven <geert+rene...@glider.be>
Reviewed-by: Peter Hurley <pe...@hurleysoftware.com>
---
v3:
  - Add Reviewed-by,

v2:
  - Drop RFC status.
---
 drivers/tty/serial/sh-sci.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 0130feb069aee02f..135f836642ab1c5a 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -1835,9 +1835,9 @@ static unsigned int sci_get_mctrl(struct uart_port *port)
 {
        /*
         * CTS/RTS is handled in hardware when supported, while nothing
-        * else is wired up. Keep it simple and simply assert DSR/CAR.
+        * else is wired up. Keep it simple and simply assert CTS/DSR/CAR.
         */
-       return TIOCM_DSR | TIOCM_CAR;
+       return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
 }
 
 static void sci_break_ctl(struct uart_port *port, int break_state)
-- 
1.9.1

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