serial: sh-sci: Don't call sci_dma_rx_push() if no data has arrived
On receive DMA time-out, avoid calling sci_dma_rx_push() if no data was
transferred by the timed out DMA request.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index ffcbf6e..d8b73e7 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -1467,10 +1467,11 @@
dev_dbg(port->dev, "Read %u bytes with cookie %d\n", read,
s->active_rx);
- count = sci_dma_rx_push(s, s->rx_buf[new], read);
-
- if (count)
- tty_flip_buffer_push(&port->state->port);
+ if (read) {
+ count = sci_dma_rx_push(s, s->rx_buf[new], read);
+ if (count)
+ tty_flip_buffer_push(&port->state->port);
+ }
spin_unlock_irqrestore(&port->lock, flags);