[libcamera-devel] [PATCH v3 16/23] libcamera: IPACameraSensorInfo: Add VBLANK

[Jacopo Mondi]

The IPA module needs the vertical blanking value to calculate the
total frame size.

In order to prepare removing usage of V4L2_CID_VBLANK in IPA modules,
add the vblank value to the IPACameraSensorInfo structure.

Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 include/libcamera/ipa/core.mojom              |  6 ++++++
 src/libcamera/camera_sensor/camera_sensor.cpp | 15 +++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/include/libcamera/ipa/core.mojom b/include/libcamera/ipa/core.mojom
index 74f3339e56f2..d122fb7add4d 100644
--- a/include/libcamera/ipa/core.mojom
+++ b/include/libcamera/ipa/core.mojom
@@ -178,6 +178,11 @@ module libcamera;
  * The total line length in pixel clock periods, including blanking.
  */
 
+/**
+ * \var IPACameraSensorInfo::vblank
+ * \brief The vertical blanking, expressed in number of lines
+ */
+
 /**
  * \var IPACameraSensorInfo::minFrameLength
  * \brief The minimum allowable frame length in units of lines
@@ -218,6 +223,7 @@ struct IPACameraSensorInfo {
 
 	uint64 pixelRate;
 	uint32 lineLength;
+	uint32 vblank;
 
 	uint32 minFrameLength;
 	uint32 maxFrameLength;
diff --git a/src/libcamera/camera_sensor/camera_sensor.cpp b/src/libcamera/camera_sensor/camera_sensor.cpp
index 02810c7c5ad0..08b96b9c3b40 100644
--- a/src/libcamera/camera_sensor/camera_sensor.cpp
+++ b/src/libcamera/camera_sensor/camera_sensor.cpp
@@ -1008,6 +1008,21 @@ int CameraSensor::sensorInfo(IPACameraSensorInfo *info) const
 	info->minFrameLength = info->outputSize.height + vblank.min().get<int32_t>();
 	info->maxFrameLength = info->outputSize.height + vblank.max().get<int32_t>();
 
+	/*
+	 * Retrieve the vertical blanking.
+	 *
+	 * We can't rely on the valued cached as vblank can be modified while
+	 * streaming to adjust the frame rate.
+	 */
+	ControlList ctrls = subdev_->getControls({ V4L2_CID_VBLANK });
+	if (ctrls.empty()) {
+		LOG(CameraSensor, Error)
+			<< "Failed to retrieve camera info controls";
+		return -EINVAL;
+	}
+
+	info->vblank = ctrls.get(V4L2_CID_VBLANK).get<int32_t>();
+
 	return 0;
 }
 
-- 
2.36.1