[media] v4l: of: check for unique lanes in data-lanes and clock-lanes

All lanes in data-lanes and clock-lanes properties should be unique. Add
a check for this in v4l2_of_parse_csi_bus() and print a warning if
duplicated lanes are found.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/media/v4l2-core/v4l2-of.c b/drivers/media/v4l2-core/v4l2-of.c
index 93b33681776c..4f59f442dd0a 100644
--- a/drivers/media/v4l2-core/v4l2-of.c
+++ b/drivers/media/v4l2-core/v4l2-of.c
@@ -26,7 +26,7 @@ static int v4l2_of_parse_csi_bus(const struct device_node *node,
         struct v4l2_of_bus_mipi_csi2 *bus = &endpoint->bus.mipi_csi2;
         struct property *prop;
         bool have_clk_lane = false;
-        unsigned int flags = 0;
+        unsigned int flags = 0, lanes_used = 0;
         u32 v;
 
         prop = of_find_property(node, "data-lanes", NULL);
@@ -38,6 +38,12 @@ static int v4l2_of_parse_csi_bus(const struct device_node *node,
                         lane = of_prop_next_u32(prop, lane, &v);
                         if (!lane)
                                 break;
+
+                        if (lanes_used & BIT(v))
+                                pr_warn("%s: duplicated lane %u in data-lanes\n",
+                                        node->full_name, v);
+                        lanes_used |= BIT(v);
+
                         bus->data_lanes[i] = v;
                 }
                 bus->num_data_lanes = i;
@@ -63,6 +69,11 @@ static int v4l2_of_parse_csi_bus(const struct device_node *node,
         }
 
         if (!of_property_read_u32(node, "clock-lanes", &v)) {
+                if (lanes_used & BIT(v))
+                        pr_warn("%s: duplicated lane %u in clock-lanes\n",
+                                node->full_name, v);
+                lanes_used |= BIT(v);
+
                 bus->clock_lane = v;
                 have_clk_lane = true;
         }