[PATCH v20 6/6] media: qcom: camss: Use data-lanes starting at 1 for new CSIPHY mode

[Bryan O'Donoghue]

Introducing a dedicated CSIPHY driver community feedback was both to move
to data-lanes starting at index 1 on the PHY side and also to match that
indexing scheme in the CSI decoder - CSID.

CSID consumes the data-lanes property to determine which CSID lanes to
switch on. For indexes starting at 1 we need to amend the logic somewhere.
The PHY side code normalises the input data to register level meanings so,
replicate that logic on the CSID side.

Introduce a simple flag to differentiate between legacy indexing @ 0 and
new indexing @ 1.

Existing bindings are not affected.

Reviewed-by: Loic Poulain <loic.poulain@xxxxxxxxxxxxxxxx>
Tested-by: Oleg Keri <okerixx@xxxxxxxxx> # Lenovo Yoga Slim 7x Gen 11 (Glymur)
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>
---
 drivers/media/platform/qcom/camss/camss-csiphy.h |  1 +
 drivers/media/platform/qcom/camss/camss.c        | 15 ++++++++++++---
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/media/platform/qcom/camss/camss-csiphy.h b/drivers/media/platform/qcom/camss/camss-csiphy.h
index 7a357044b9fdb..8c3319f2ca1cf 100644
--- a/drivers/media/platform/qcom/camss/camss-csiphy.h
+++ b/drivers/media/platform/qcom/camss/camss-csiphy.h
@@ -21,6 +21,7 @@
 #define MSM_CSIPHY_PAD_SINK 0
 #define MSM_CSIPHY_PAD_SRC 1
 #define MSM_CSIPHY_PADS_NUM 2
+#define MSM_CSIPHY_MAX_DATA_LANE 4
 
 #define CSIPHY_GRP_ID 1
 
diff --git a/drivers/media/platform/qcom/camss/camss.c b/drivers/media/platform/qcom/camss/camss.c
index 84097d82d99c9..6f58e729eaceb 100644
--- a/drivers/media/platform/qcom/camss/camss.c
+++ b/drivers/media/platform/qcom/camss/camss.c
@@ -4742,7 +4742,8 @@ static const struct parent_dev_ops vfe_parent_dev_ops = {
  */
 static int camss_parse_endpoint_node(struct device *dev,
 				     struct fwnode_handle *ep,
-				     struct camss_async_subdev *csd)
+				     struct camss_async_subdev *csd,
+				     u8 lane_base)
 {
 	struct csiphy_lanes_cfg *lncfg = &csd->interface.csi2.lane_cfg;
 	struct v4l2_mbus_config_mipi_csi2 *mipi_csi2;
@@ -4777,7 +4778,14 @@ static int camss_parse_endpoint_node(struct device *dev,
 		return -ENOMEM;
 
 	for (i = 0; i < lncfg->num_data; i++) {
-		lncfg->data[i].pos = mipi_csi2->data_lanes[i];
+		u8 lane = mipi_csi2->data_lanes[i];
+
+		if (lane < lane_base || lane - lane_base >= MSM_CSIPHY_MAX_DATA_LANE) {
+			dev_err(dev, "invalid data-lane %u\n", lane);
+			return -EINVAL;
+		}
+
+		lncfg->data[i].pos = mipi_csi2->data_lanes[i] - lane_base;
 		lncfg->data[i].pol = mipi_csi2->lane_polarities[i + 1];
 	}
 
@@ -4794,6 +4802,7 @@ static int camss_parse_ports(struct camss *camss)
 {
 	struct device *dev = camss->dev;
 	struct fwnode_handle *fwnode = dev_fwnode(dev), *ep;
+	u8 lane_base = camss->legacy_phy ? 0 : 1;
 	int ret;
 
 	fwnode_graph_for_each_endpoint(fwnode, ep) {
@@ -4841,7 +4850,7 @@ static int camss_parse_ports(struct camss *camss)
 			goto err_cleanup;
 		}
 
-		ret = camss_parse_endpoint_node(dev, ep, csd);
+		ret = camss_parse_endpoint_node(dev, ep, csd, lane_base);
 		if (ret < 0)
 			goto err_cleanup;
 	}

-- 
2.55.0