[libcamera-devel] [RFC 6/6] libcamera: camera_sensor: Collect camera properties

[Jacopo Mondi]

Store the camera sensor location and rotation by parsing the
associated V4L2 controls.

Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 src/libcamera/camera_sensor.cpp       | 32 +++++++++++++++++++++++++++
 src/libcamera/include/camera_sensor.h |  3 +++
 2 files changed, 35 insertions(+)

diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp
index 86f0c772861b..857853f4fcf9 100644
--- a/src/libcamera/camera_sensor.cpp
+++ b/src/libcamera/camera_sensor.cpp
@@ -13,6 +13,8 @@
 #include <limits.h>
 #include <math.h>
 
+#include <libcamera/property_ids.h>
+
 #include "formats.h"
 #include "utils.h"
 #include "v4l2_subdevice.h"
@@ -89,6 +91,36 @@ int CameraSensor::init()
 	if (ret < 0)
 		return ret;
 
+	/* Retrieve and store the camera sensor properties. */
+	const ControlInfoMap &controls = subdev_->controls();
+	int32_t controlValue = V4L2_LOCATION_EXTERNAL;
+
+	const auto &locationControl = controls.find(V4L2_CID_CAMERA_SENSOR_LOCATION);
+	if (locationControl != controls.end())
+		controlValue = locationControl->second.defaultValue().get<int32_t>();
+
+	switch (controlValue) {
+	case V4L2_LOCATION_EXTERNAL:
+		location_ = CAMERA_LOCATION_EXTERNAL;
+		break;
+	case V4L2_LOCATION_FRONT:
+		location_ = CAMERA_LOCATION_FRONT;
+		break;
+	case V4L2_LOCATION_BACK:
+		location_ = CAMERA_LOCATION_BACK;
+		break;
+	default:
+		LOG(CameraSensor, Error)
+			<< "Unsupported camera location: " << controlValue;
+		return -EINVAL;
+	}
+
+	controlValue = 0;
+	const auto &rotationControl = controls.find(V4L2_CID_CAMERA_SENSOR_ROTATION);
+	if (rotationControl != controls.end())
+		controlValue = rotationControl->second.defaultValue().get<int32_t>();
+	rotation_ = controlValue;
+
 	/* Enumerate and cache media bus codes and sizes. */
 	const ImageFormats formats = subdev_->formats(0);
 	if (formats.isEmpty()) {
diff --git a/src/libcamera/include/camera_sensor.h b/src/libcamera/include/camera_sensor.h
index 1fb36a4f4951..ee26ca20ac20 100644
--- a/src/libcamera/include/camera_sensor.h
+++ b/src/libcamera/include/camera_sensor.h
@@ -56,6 +56,9 @@ private:
 
 	std::vector<unsigned int> mbusCodes_;
 	std::vector<Size> sizes_;
+
+	unsigned int location_;
+	unsigned int rotation_;
 };
 
 } /* namespace libcamera */
-- 
2.23.0