[PATCH] tty/serial: at91: BUG: disable interrupts when !UART_ENABLE_MS()

[Richard Genoud]

In set_termios(), interrupts where not disabled if UART_ENABLE_MS() was
false.

Tested on at91sam9g35.

CC: stable at vger.kernel.org # >= 3.16

Signed-off-by: Richard Genoud <richard.genoud at gmail.com>
---
 drivers/tty/serial/atmel_serial.c | 43 ++++++++++++++++++++++++++++++++++++++-
 1 file changed, 42 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 7b63677475c1..d7d4584549a5 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -527,6 +527,45 @@ static void atmel_enable_ms(struct uart_port *port)
 }
 
 /*
+ * Disable modem status interrupts
+ */
+static void atmel_disable_ms(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	uint32_t idr = 0;
+
+	/*
+	 * Interrupt should not be disabled twice
+	 */
+	if (!atmel_port->ms_irq_enabled)
+		return;
+
+	atmel_port->ms_irq_enabled = false;
+
+	if (atmel_port->gpio_irq[UART_GPIO_CTS] >= 0)
+		disable_irq(atmel_port->gpio_irq[UART_GPIO_CTS]);
+	else
+		idr |= ATMEL_US_CTSIC;
+
+	if (atmel_port->gpio_irq[UART_GPIO_DSR] >= 0)
+		disable_irq(atmel_port->gpio_irq[UART_GPIO_DSR]);
+	else
+		idr |= ATMEL_US_DSRIC;
+
+	if (atmel_port->gpio_irq[UART_GPIO_RI] >= 0)
+		disable_irq(atmel_port->gpio_irq[UART_GPIO_RI]);
+	else
+		idr |= ATMEL_US_RIIC;
+
+	if (atmel_port->gpio_irq[UART_GPIO_DCD] >= 0)
+		disable_irq(atmel_port->gpio_irq[UART_GPIO_DCD]);
+	else
+		idr |= ATMEL_US_DCDIC;
+
+	UART_PUT_IDR(port, idr);
+}
+
+/*
  * Control the transmission of a break signal
  */
 static void atmel_break_ctl(struct uart_port *port, int break_state)
@@ -1993,7 +2032,9 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 
 	/* CTS flow-control and modem-status interrupts */
 	if (UART_ENABLE_MS(port, termios->c_cflag))
-		port->ops->enable_ms(port);
+		atmel_enable_ms(port);
+	else
+		atmel_disable_ms(port);
 
 	spin_unlock_irqrestore(&port->lock, flags);
 }
-- 
2.0.0