1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 2a1d52fb4936..f119d1761106 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -1240,6 +1240,21 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
         spin_unlock_irqrestore(&port->lock, flags);
 }
 
+static void atmel_set_ldisc(struct uart_port *port, int new)
+{
+        int line = port->line;
+
+        if (line >= port->state->port.tty->driver->num)
+                return;
+
+        if (port->state->port.tty->ldisc->ops->num == N_PPS) {
+                port->flags |= UPF_HARDPPS_CD;
+                atmel_enable_ms(port);
+        } else {
+                port->flags &= ~UPF_HARDPPS_CD;
+        }
+}
+
 /*
  * Return string describing the specified port
  */
@@ -1380,6 +1395,7 @@ static struct uart_ops atmel_pops = {
         .shutdown       = atmel_shutdown,
         .flush_buffer   = atmel_flush_buffer,
         .set_termios    = atmel_set_termios,
+        .set_ldisc      = atmel_set_ldisc,
         .type           = atmel_type,
         .release_port   = atmel_release_port,
         .request_port   = atmel_request_port,