1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index a183aceb6d15..a576a5bc2d15 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -1535,6 +1535,8 @@ static int pl011_startup(struct uart_port *port)
         /*
          * Provoke TX FIFO interrupt into asserting.
          */
+        spin_lock_irq(&uap->port.lock);
+
         cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE;
         writew(cr, uap->port.membase + UART011_CR);
         writew(0, uap->port.membase + UART011_FBRD);
@@ -1559,6 +1561,8 @@ static int pl011_startup(struct uart_port *port)
         cr |= UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
         writew(cr, uap->port.membase + UART011_CR);
 
+        spin_unlock_irq(&uap->port.lock);
+
         /*
          * initialise the old status of the modem signals
          */
@@ -1627,11 +1631,13 @@ static void pl011_shutdown(struct uart_port *port)
          * it during startup().
          */
         uap->autorts = false;
+        spin_lock_irq(&uap->port.lock);
         cr = readw(uap->port.membase + UART011_CR);
         uap->old_cr = cr;
         cr &= UART011_CR_RTS | UART011_CR_DTR;
         cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
         writew(cr, uap->port.membase + UART011_CR);
+        spin_unlock_irq(&uap->port.lock);
 
         /*
          * disable break condition and fifos