[PATCH] media: qcom: camss: Read lane config from PHY endpoint for PHY API path

[Nihal Kumar Gupta]

In the new PHY API topology the CAMSS endpoint carries only port/ID
information. The bus-type and data-lane configuration are described on
the PHY node's sensor-side endpoint (port@0), not on the CAMSS endpoint.

Add a phy_in parameter to camss_parse_endpoint_node(). Extract csiphy_id
from the CAMSS endpoint port number and read bus-type and lane properties
from phy_in. Check fwnode_device_is_available() on the PHY node and skip
disabled PHYs. Fix missing fwnode_handle_put() on the disabled-PHY early
exit path. For legacy DTS phy_in is the CAMSS endpoint itself so existing
behaviour is preserved.

Signed-off-by: Nihal Kumar Gupta <nihal.gupta@xxxxxxxxxxxxxxxx>
---
 drivers/media/platform/qcom/camss/camss.c | 49 +++++++++++++++++------
 1 file changed, 36 insertions(+), 13 deletions(-)

diff --git a/drivers/media/platform/qcom/camss/camss.c b/drivers/media/platform/qcom/camss/camss.c
index 84097d82d99c..7254f2b28eb0 100644
--- a/drivers/media/platform/qcom/camss/camss.c
+++ b/drivers/media/platform/qcom/camss/camss.c
@@ -4742,11 +4742,13 @@ static const struct parent_dev_ops vfe_parent_dev_ops = {
  */
 static int camss_parse_endpoint_node(struct device *dev,
 				     struct fwnode_handle *ep,
+				     struct fwnode_handle *phy_in,
 				     struct camss_async_subdev *csd)
 {
 	struct csiphy_lanes_cfg *lncfg = &csd->interface.csi2.lane_cfg;
 	struct v4l2_mbus_config_mipi_csi2 *mipi_csi2;
 	struct v4l2_fwnode_endpoint vep = { { 0 } };
+	struct v4l2_fwnode_endpoint phy_vep = { { 0 } };
 	unsigned int i;
 	int ret;
 
@@ -4754,18 +4756,26 @@ static int camss_parse_endpoint_node(struct device *dev,
 	if (ret)
 		return ret;
 
+	csd->interface.csiphy_id = vep.base.port;
+
+	/* bus-type and lane config from csiphy endpoint (phy_in) */
+	ret = v4l2_fwnode_endpoint_parse(phy_in, &phy_vep);
+	if (ret) {
+		dev_err(dev, "parse_endpoint: failed to parse phy_in ep (%pfw): %d\n",
+			phy_in, ret);
+		return ret;
+	}
+
 	/*
 	 * Most SoCs support both D-PHY and C-PHY standards, but currently only
 	 * D-PHY is supported in the driver.
 	 */
-	if (vep.bus_type != V4L2_MBUS_CSI2_DPHY) {
-		dev_err(dev, "Unsupported bus type %d\n", vep.bus_type);
+	if (phy_vep.bus_type != V4L2_MBUS_CSI2_DPHY) {
+		dev_err(dev, "Unsupported bus type %d\n", phy_vep.bus_type);
 		return -EINVAL;
 	}
 
-	csd->interface.csiphy_id = vep.base.port;
-
-	mipi_csi2 = &vep.bus.mipi_csi2;
+	mipi_csi2 = &phy_vep.bus.mipi_csi2;
 	lncfg->clk.pos = mipi_csi2->clock_lane;
 	lncfg->clk.pol = mipi_csi2->lane_polarities[0];
 	lncfg->num_data = mipi_csi2->num_data_lanes;
@@ -4798,15 +4808,15 @@ static int camss_parse_ports(struct camss *camss)
 
 	fwnode_graph_for_each_endpoint(fwnode, ep) {
 		struct camss_async_subdev *csd;
-
-		if (!fwnode_device_is_available(ep))
-			continue;
+		struct fwnode_handle *phy_in;
 
 		if (camss->legacy_phy) {
 			csd = v4l2_async_nf_add_fwnode_remote(&camss->notifier, ep,
 							      typeof(*csd));
+			/* legacy DTS has bus-type/data-lanes on the camss endpoint */
+			phy_in = fwnode_handle_get(ep);
 		} else {
-			struct fwnode_handle *phy_out, *phy_node, *phy_in, *sensor_ep;
+			struct fwnode_handle *phy_out, *phy_node, *sensor_ep;
 
 			phy_out = fwnode_graph_get_remote_endpoint(ep);
 			if (!phy_out)
@@ -4817,31 +4827,44 @@ static int camss_parse_ports(struct camss *camss)
 			if (!phy_node)
 				continue;
 
+			if (!fwnode_device_is_available(phy_node)) {
+				dev_info(dev, "parse_ports: phy_node=%s disabled\n",
+				 of_node_full_name(to_of_node(phy_node)));
+				continue;
+			};
+
+			/* port@0 of the phy node is the sensor-side input port */
 			phy_in = fwnode_graph_get_endpoint_by_id(phy_node, 0, 0, 0);
 			fwnode_handle_put(phy_node);
-			if (!phy_in)
+			if (!phy_in) {
+				dev_info(dev, "parse_ports: csiphy port@0 has no endpoint, skip\n");
 				continue;
+			};
 
 			sensor_ep = fwnode_graph_get_remote_endpoint(phy_in);
-			fwnode_handle_put(phy_in);
-			if (!sensor_ep)
+			if (!sensor_ep) {
+				fwnode_handle_put(phy_in);
 				continue;
+			};
 
 			csd = v4l2_async_nf_add_fwnode(&camss->notifier, sensor_ep,
 						struct camss_async_subdev);
 			fwnode_handle_put(sensor_ep);
 			if (IS_ERR(csd)) {
+				fwnode_handle_put(phy_in);
 				ret = PTR_ERR(csd);
 				goto err_cleanup;
 			}
 		}
 
 		if (IS_ERR(csd)) {
+			fwnode_handle_put(phy_in);
 			ret = PTR_ERR(csd);
 			goto err_cleanup;
 		}
 
-		ret = camss_parse_endpoint_node(dev, ep, csd);
+		ret = camss_parse_endpoint_node(dev, ep, phy_in, csd);
+		fwnode_handle_put(phy_in);
 		if (ret < 0)
 			goto err_cleanup;
 	}
-- 
2.34.1