[PATCH 2/3] media: Add lane checks for Cadence CSI2RX

[Jan Kotas]

This patch adds lane checks for CSI2RX, to prevent clock lane
being used as a data lane.

Signed-off-by: Jan Kotas <j...@cadence.com>
---
 drivers/media/platform/cadence/cdns-csi2rx.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c 
b/drivers/media/platform/cadence/cdns-csi2rx.c
index 31ace114e..97ec09e72 100644
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -2,7 +2,7 @@
 /*
  * Driver for Cadence MIPI-CSI2 RX Controller v1.3
  *
- * Copyright (C) 2017 Cadence Design Systems Inc.
+ * Copyright (C) 2017-2019 Cadence Design Systems Inc.
  */
 
 #include <linux/clk.h>
@@ -364,7 +364,7 @@ static int csi2rx_parse_dt(struct csi2rx_priv *csi2rx)
        struct v4l2_fwnode_endpoint v4l2_ep = { .bus_type = 0 };
        struct fwnode_handle *fwh;
        struct device_node *ep;
-       int ret;
+       int ret, i;
 
        ep = of_graph_get_endpoint_by_regs(csi2rx->dev->of_node, 0, 0);
        if (!ep)
@@ -395,6 +395,15 @@ static int csi2rx_parse_dt(struct csi2rx_priv *csi2rx)
                return -EINVAL;
        }
 
+       for (i = 0; i < csi2rx->num_lanes; i++) {
+               if (csi2rx->lanes[i] < 1) {
+                       dev_err(csi2rx->dev, "Invalid lane[%d] number: %u\n",
+                               i, csi2rx->lanes[i]);
+                       of_node_put(ep);
+                       return -EINVAL;
+               }
+       }
+
        csi2rx->asd.match.fwnode = fwnode_graph_get_remote_port_parent(fwh);
        csi2rx->asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
        of_node_put(ep);
-- 
2.15.0