serial: pl011: fix fall back from DMA to interrupt mode

When falling back from DMA to interrupt mode the receive interrupt has to
be re-enabled to catch new incoming data.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index ea6c2a3798ff..d58783d364e3 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -967,6 +967,8 @@ static void pl011_dma_rx_poll(unsigned long args)
 
                 spin_lock_irqsave(&uap->port.lock, flags);
                 pl011_dma_rx_stop(uap);
+                uap->im |= UART011_RXIM;
+                writew(uap->im, uap->port.membase + UART011_IMSC);
                 spin_unlock_irqrestore(&uap->port.lock, flags);
 
                 uap->dmarx.running = false;