sc16is7xx: Don't spin if no data received

See: https://github.com/raspberrypi/linux/issues/2676

Signed-off-by: Phil Elwell <phil@raspberrypi.org>

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 55b178c..7789d35 100644 (file)
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -678,6 +678,8 @@ static bool sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
                        rxlen = sc16is7xx_port_read(port, SC16IS7XX_RXLVL_REG);
                        if (rxlen)
                                sc16is7xx_handle_rx(port, rxlen, iir);
+                       else
+                               return false;
                        break;
                case SC16IS7XX_IIR_THRI_SRC:
                        sc16is7xx_handle_tx(port);