[PATCH v5 1/4] serial: sh-sci: Extract sci_dma_rx_chan_invalidate()

[Geert Uytterhoeven <geert+renesas@glider.be>]

The cookies and channel pointer for the DMA receive channel are
invalidated in two places, and one more is planned.
Extract this functionality in a common helper.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v5:
  - New.
---
 drivers/tty/serial/sh-sci.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 8df0fd8245203f8b..4c75468680cb547d 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -1243,12 +1243,22 @@ static int sci_dma_rx_find_active(struct sci_port *s)
 	return -1;
 }
 
+static void sci_dma_rx_chan_invalidate(struct sci_port *s)
+{
+	unsigned int i;
+
+	s->chan_rx = NULL;
+	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
+		s->cookie_rx[i] = -EINVAL;
+	s->active_rx = 0;
+}
+
 static void sci_rx_dma_release(struct sci_port *s)
 {
 	struct dma_chan *chan = s->chan_rx_saved;
 
-	s->chan_rx_saved = s->chan_rx = NULL;
-	s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
+	s->chan_rx_saved = NULL;
+	sci_dma_rx_chan_invalidate(s);
 	dmaengine_terminate_sync(chan);
 	dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
 			  sg_dma_address(&s->sg_rx[0]));
@@ -1367,10 +1377,7 @@ static int sci_submit_rx(struct sci_port *s, bool port_lock_held)
 		spin_lock_irqsave(&port->lock, flags);
 	if (i)
 		dmaengine_terminate_async(chan);
-	for (i = 0; i < 2; i++)
-		s->cookie_rx[i] = -EINVAL;
-	s->active_rx = 0;
-	s->chan_rx = NULL;
+	sci_dma_rx_chan_invalidate(s);
 	sci_start_rx(port);
 	if (!port_lock_held)
 		spin_unlock_irqrestore(&port->lock, flags);
-- 
2.17.1