[PATCH v2 17/21] media: i2c: it6625: require a DT endpoint and simplify endpoint parsing

[Hermes Wu via B4 Relay <devnull+Hermes.wu.ite.com.tw@kernel.org>]

From: Hermes Wu <Hermes.wu@ite.com.tw>

it6625_init_data() preset csi_lanes/port_num/bus_type before DT
parsing ran, and it6625_parse_endpoint() fell back to those hardcoded
defaults whenever no CSI-2 endpoint node was found instead of failing.
The binding requires port@0, so a missing endpoint should surface as a
probe error, not silently apply a hardcoded D-PHY/4-lane
configuration.

Drop the presets from it6625_init_data() -- these values must come
only from DT -- and delete the no-endpoint fallback entirely rather
than reshaping it. This is safe: of_fwnode_handle(NULL) returns NULL,
and v4l2_fwnode_endpoint_alloc_parse() -> __v4l2_fwnode_endpoint_parse()
already returns -EPROBE_DEFER for a NULL fwnode before touching
anything else, which is a strictly better result for the no-endpoint
case than a driver-local -EINVAL.

While here, consolidate the three -EINVAL return sites in
it6625_parse_endpoint() through a single error-path label instead of
repeating v4l2_fwnode_endpoint_free() at each one.

Signed-off-by: Hermes Wu <Hermes.wu@ite.com.tw>
---
 drivers/media/i2c/it6625.c | 32 +++++++++++---------------------
 1 file changed, 11 insertions(+), 21 deletions(-)

diff --git a/drivers/media/i2c/it6625.c b/drivers/media/i2c/it6625.c
index 7637418c5a214d32f75d197a1e0ba1bffe7235f9..01200acb6bda5cdd759caf70642fcd910284a8b8 100644
--- a/drivers/media/i2c/it6625.c
+++ b/drivers/media/i2c/it6625.c
@@ -2074,9 +2074,6 @@ static void it6625_init_data(struct it6625 *it6625)
 	static struct v4l2_dv_timings default_timing =
 			V4L2_DV_BT_CEA_1920X1080P60;
 
-	it6625->csi_lanes = 4;
-	it6625->port_num = 1;
-	it6625->bus_type = V4L2_MBUS_CSI2_DPHY;
 	it6625->csi_format = it6625_formats[0].csi_format;
 	it6625->mbus_fmt_code = it6625_formats[0].mbus_fmt_code;
 	it6625->timings = default_timing;
@@ -2122,33 +2119,24 @@ static int it6625_parse_endpoint(struct it6625 *it6625)
 			of_node_put(port_ep);
 	}
 
-	if (!ep) {
-		it6625->port_num = 1;
-		dev_dbg(dev, "no CSI-2 endpoint node found, using default %u CSI lanes",
-			it6625->csi_lanes);
-		return 0;
-	}
-
 	ret = v4l2_fwnode_endpoint_alloc_parse(of_fwnode_handle(ep), &endpoint);
 	of_node_put(ep);
-	if (ret) {
-		dev_err(dev, "failed to parse endpoint: %d", ret);
-		return ret;
-	}
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to parse endpoint");
 
 	if (endpoint.bus_type != V4L2_MBUS_CSI2_DPHY &&
 	    endpoint.bus_type != V4L2_MBUS_CSI2_CPHY) {
 		dev_err(dev, "unsupported bus type %d, expected CSI-2 D-PHY or C-PHY",
 			endpoint.bus_type);
-		v4l2_fwnode_endpoint_free(&endpoint);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_free_endpoint;
 	}
 
 	if (endpoint.bus_type == V4L2_MBUS_CSI2_CPHY &&
 	    it6625->chip_type != IT6626_CHIP) {
 		dev_err(dev, "IT6625 does not support C-PHY, only IT6626 does");
-		v4l2_fwnode_endpoint_free(&endpoint);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_free_endpoint;
 	}
 
 	max_lanes = (endpoint.bus_type == V4L2_MBUS_CSI2_CPHY) ? 3 : 4;
@@ -2158,15 +2146,17 @@ static int it6625_parse_endpoint(struct it6625 *it6625)
 		dev_err(dev,
 			"invalid number of CSI data lanes: %u (max %u for this bus type)",
 			endpoint.bus.mipi_csi2.num_data_lanes, max_lanes);
-		v4l2_fwnode_endpoint_free(&endpoint);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto out_free_endpoint;
 	}
 
 	it6625->csi_lanes = endpoint.bus.mipi_csi2.num_data_lanes;
 	it6625->bus_type = endpoint.bus_type;
+
+out_free_endpoint:
 	v4l2_fwnode_endpoint_free(&endpoint);
 
-	return 0;
+	return ret;
 }
 
 static int it6625_parse_dt(struct it6625 *it6625)

-- 
2.34.1