[libcamera-devel] [PATCH v3 4/6] libcamera: camera_sensor: Add V4L2 control operations

[Jacopo Mondi]

Add operations to get and set control and to retrieve the informations
on a V4L2 control. For simple camera sensors, the operations are
directly called on the underlying V4L2 subdevice.

Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 src/libcamera/camera_sensor.cpp       | 58 +++++++++++++++++++++++++++
 src/libcamera/include/camera_sensor.h |  6 +++
 2 files changed, 64 insertions(+)

diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp
index cb6649efac3f..73e870b6cc98 100644
--- a/src/libcamera/camera_sensor.cpp
+++ b/src/libcamera/camera_sensor.cpp
@@ -249,6 +249,64 @@ int CameraSensor::setFormat(V4L2SubdeviceFormat *format)
 	return subdev_->setFormat(0, format);
 }
 
+/**
+ * \brief Retrieve the V4L2 control info from the sensor's subdevice
+ * \param id The V4L2 control id
+ *
+ * Retrieve the V4L2ControlInfo from the V4L2 subdevice backing the
+ * camera sensor.
+ *
+ * More complex camera sensors, which expose multiple subdevices should
+ * override this method.
+ *
+ * \sa V4L2Device::getControlInfo()
+ *
+ * \return The V4L2ControlInfo associated to the V4L2 control with \a id or
+ * nullptr if the control is not supported.
+ */
+V4L2ControlInfo *CameraSensor::getControlInfo(unsigned int id)
+{
+	return subdev_->getControlInfo(id);
+}
+
+/**
+ * \brief Read a list of controls from the sensor's subdevice
+ * \param ctrls The list of controls to read
+ *
+ * Read V4L2 controls values on the V4L2 subdevice backing the
+ * camera sensor.
+ *
+ * More complex camera sensors, which expose multiple subdevices should
+ * override this method.
+ *
+ * \sa V4L2Device::getControls()
+ *
+ * \return 0 on success or a negative error code otherwise
+ */
+int CameraSensor::getControls(V4L2Controls *ctrls)
+{
+	return subdev_->getControls(ctrls);
+}
+
+/**
+ * \brief Write a list of controls from the sensor's subdevice
+ * \param ctrls The list of controls to write
+ *
+ * Write V4L2 controls values on the V4L2 subdevice backing the
+ * camera sensor.
+ *
+ * More complex camera sensors, which expose multiple subdevices should
+ * override this method.
+ *
+ * \sa V4L2Device::setControls()
+ *
+ * \return 0 on success or a negative error code otherwise
+ */
+int CameraSensor::setControls(V4L2Controls *ctrls)
+{
+	return subdev_->setControls(ctrls);
+}
+
 std::string CameraSensor::logPrefix() const
 {
 	return "'" + subdev_->entity()->name() + "'";
diff --git a/src/libcamera/include/camera_sensor.h b/src/libcamera/include/camera_sensor.h
index b823480241a7..ed6bb16f5686 100644
--- a/src/libcamera/include/camera_sensor.h
+++ b/src/libcamera/include/camera_sensor.h
@@ -17,6 +17,8 @@
 namespace libcamera {
 
 class MediaEntity;
+class V4L2ControlInfo;
+class V4L2Controls;
 class V4L2Subdevice;
 
 struct V4L2SubdeviceFormat;
@@ -41,6 +43,10 @@ public:
 				      const Size &size) const;
 	int setFormat(V4L2SubdeviceFormat *format);
 
+	V4L2ControlInfo *getControlInfo(unsigned int id);
+	int getControls(V4L2Controls *ctrls);
+	int setControls(V4L2Controls *ctrls);
+
 protected:
 	std::string logPrefix() const;
 
-- 
2.21.0