[libcamera-devel] [PATCH 3/3] libcamera: camera_sensor: Check control availability from idmap

[Laurent Pinchart]

The presence of mandatory and optional controls is checked in
CameraSensor::validateSensorDriver() by trying to retrieve them. This
cases an error message to be printed in the V4L2Device class if an
optional control isn't present, while this isn't an error.

To fix this, use the control idmap reported by the V4L2Device to check
for control availability. The function can now print the whole list of
missing controls, making debugging easier.

Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
 src/libcamera/camera_sensor.cpp | 31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp
index 10713d3a0c29..85813befbf58 100644
--- a/src/libcamera/camera_sensor.cpp
+++ b/src/libcamera/camera_sensor.cpp
@@ -250,14 +250,18 @@ int CameraSensor::validateSensorDriver()
 	 * Optional controls are used to register optional sensor properties. If
 	 * not present, some values will be defaulted.
 	 */
-	const std::vector<uint32_t> optionalControls{
+	static constexpr uint32_t optionalControls[] = {
 		V4L2_CID_CAMERA_ORIENTATION,
 		V4L2_CID_CAMERA_SENSOR_ROTATION,
 	};
 
-	ControlList ctrls = subdev_->getControls(optionalControls);
-	if (ctrls.empty())
-		LOG(CameraSensor, Debug) << "Optional V4L2 controls not supported";
+	const ControlIdMap &controls = subdev_->controls().idmap();
+	for (uint32_t ctrl : optionalControls) {
+		if (!controls.count(ctrl))
+			LOG(CameraSensor, Debug)
+				<< "Optional V4L2 control " << utils::hex(ctrl)
+				<< " not supported";
+	}
 
 	/*
 	 * Make sure the required selection targets are supported.
@@ -312,21 +316,28 @@ int CameraSensor::validateSensorDriver()
 	 * For raw sensors, make sure the sensor driver supports the controls
 	 * required by the CameraSensor class.
 	 */
-	const std::vector<uint32_t> mandatoryControls{
+	static constexpr uint32_t mandatoryControls[] = {
 		V4L2_CID_EXPOSURE,
 		V4L2_CID_HBLANK,
 		V4L2_CID_PIXEL_RATE,
 	};
 
-	ctrls = subdev_->getControls(mandatoryControls);
-	if (ctrls.empty()) {
-		LOG(CameraSensor, Error)
-			<< "Mandatory V4L2 controls not available";
+	err = 0;
+	for (uint32_t ctrl : mandatoryControls) {
+		if (!controls.count(ctrl)) {
+			LOG(CameraSensor, Error)
+				<< "Mandatory V4L2 control " << utils::hex(ctrl)
+				<< " not available";
+			err = -EINVAL;
+		}
+	}
+
+	if (err) {
 		LOG(CameraSensor, Error)
 			<< "The sensor kernel driver needs to be fixed";
 		LOG(CameraSensor, Error)
 			<< "See Documentation/sensor_driver_requirements.rst in the libcamera sources for more information";
-		return -EINVAL;
+		return err;
 	}
 
 	return 0;
-- 
Regards,

Laurent Pinchart