serial: MPSC: Stop rx engine when CREAD cleared

Currently, the MPSC driver doesn't stop recieving characters when the CREAD
flag in termios->c_cflag is cleared.  It should.  Also, only start receiving
if its not already started.

Signed-off-by: Stephane Chazelas <stephane@artesyncp.com>
Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 5 deletions

diff --git a/drivers/serial/mpsc.c b/drivers/serial/mpsc.c
index 567fa789c5c7..e984abf3e4d9 100644
--- a/drivers/serial/mpsc.c
+++ b/drivers/serial/mpsc.c
@@ -1520,7 +1520,6 @@ mpsc_set_termios(struct uart_port *port, struct ktermios *termios,
         mpsc_set_baudrate(pi, baud);
 
         /* Characters/events to read */
-        pi->rcv_data = 1;
         pi->port.read_status_mask = SDMA_DESC_CMDSTAT_OR;
 
         if (termios->c_iflag & INPCK)
@@ -1544,11 +1543,15 @@ mpsc_set_termios(struct uart_port *port, struct ktermios *termios,
                         pi->port.ignore_status_mask |= SDMA_DESC_CMDSTAT_OR;
         }
 
-        /* Ignore all chars if CREAD not set */
-        if (!(termios->c_cflag & CREAD))
+        if ((termios->c_cflag & CREAD)) {
+                if (!pi->rcv_data) {
+                        pi->rcv_data = 1;
+                        mpsc_start_rx(pi);
+                }
+        } else if (pi->rcv_data) {
+                mpsc_stop_rx(port);
                 pi->rcv_data = 0;
-        else
-                mpsc_start_rx(pi);
+        }
 
         spin_unlock_irqrestore(&pi->port.lock, flags);
         return;