libcamera: camera_sensor: Apply flips at setFormat()

Augment the CameraSensor::setFormat() function to configure horizontal
and vertical flips before applying the image format on the sensor.

Applying flips before format is crucial as they might change the Bayer
pattern ordering.

To allow users of the CameraSensor class to specify a Transform,
add to the V4L2SubdeviceFormat class a 'transform' member, by
default initialized to Transform::Identity.

Moving the handling of H/V flips to the CameraSensor class allows to
remove quite some boilerplate code from the IPU3 and RaspberryPi
pipeline handlers.

No functional changes intended.

Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Reviewed-by: David Plowman <david.plowman@raspberrypi.com>

1 files changed, 7 insertions, 20 deletions

diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
index c086a69a..d8232ff8 100644
--- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
+++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
@@ -691,24 +691,12 @@ int PipelineHandlerRPi::configure(Camera *camera, CameraConfiguration *config)
 		}
 	}
 
-	/*
-	 * Configure the H/V flip controls based on the combination of
-	 * the sensor and user transform.
-	 */
-	if (data->supportsFlips_) {
-		const RPiCameraConfiguration *rpiConfig =
-			static_cast<const RPiCameraConfiguration *>(config);
-		ControlList controls;
-
-		controls.set(V4L2_CID_HFLIP,
-			     static_cast<int32_t>(!!(rpiConfig->combinedTransform_ & Transform::HFlip)));
-		controls.set(V4L2_CID_VFLIP,
-			     static_cast<int32_t>(!!(rpiConfig->combinedTransform_ & Transform::VFlip)));
-		data->setSensorControls(controls);
-	}
-
 	/* First calculate the best sensor mode we can use based on the user request. */
 	V4L2SubdeviceFormat sensorFormat = findBestFormat(data->sensorFormats_, rawStream ? sensorSize : maxSize, bitDepth);
+	/* Apply any cached transform. */
+	const RPiCameraConfiguration *rpiConfig = static_cast<const RPiCameraConfiguration *>(config);
+	sensorFormat.transform = rpiConfig->combinedTransform_;
+	/* Finally apply the format on the sensor. */
 	ret = data->sensor_->setFormat(&sensorFormat);
 	if (ret)
 		return ret;
@@ -1293,10 +1281,9 @@ int PipelineHandlerRPi::registerCamera(MediaDevice *unicam, MediaDevice *isp, Me
 	 * We cache three things about the sensor in relation to transforms
 	 * (meaning horizontal and vertical flips).
 	 *
-	 * Firstly, does it support them?
-	 * Secondly, if you use them does it affect the Bayer ordering?
-	 * Thirdly, what is the "native" Bayer order, when no transforms are
-	 * applied?
+	 * If flips are supported verify if they affect the Bayer ordering
+	 * and what the "native" Bayer order is, when no transforms are
+	 * applied.
 	 *
 	 * We note that the sensor's cached list of supported formats is
 	 * already in the "native" order, with any flips having been undone.