[libcamera-devel] [PATCH v2 03/13] libcamera: ipu3: Always import buffers for ImgU sinks

[Niklas Söderlund]

When the IPU3 pipeline was first developed sinks of the ImgU that where
not active still needed to have buffers allocated to allow streaming to
start. This is no longer true, it's enough that the sinks have imported
buffers to allow streaming to start. As we already need to import
buffers for stream that are active we can align the two cases and always
import buffers.

With this there is no longer a reason to store the allocated
FrameBuffers to keep them alive and the vector tracking them can be
removed.

Signed-off-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo at jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
* Changes since v1
- Add comment
- Update commit message
---
 src/libcamera/pipeline/ipu3/ipu3.cpp | 26 +++++++-------------------
 1 file changed, 7 insertions(+), 19 deletions(-)

diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index 405550b1302fb370..f35672f4761659f4 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -49,7 +49,6 @@ public:
 		V4L2VideoDevice *dev;
 		unsigned int pad;
 		std::string name;
-		std::vector<std::unique_ptr<FrameBuffer>> buffers;
 	};
 
 	ImgUDevice()
@@ -1124,9 +1123,6 @@ int ImgUDevice::configureOutput(ImgUOutput *output,
  */
 int ImgUDevice::allocateBuffers(IPU3CameraData *data, unsigned int bufferCount)
 {
-	IPU3Stream *outStream = &data->outStream_;
-	IPU3Stream *vfStream = &data->vfStream_;
-
 	/* Share buffers between CIO2 output and ImgU input. */
 	int ret = input_->importBuffers(bufferCount);
 	if (ret) {
@@ -1148,27 +1144,19 @@ int ImgUDevice::allocateBuffers(IPU3CameraData *data, unsigned int bufferCount)
 	}
 
 	/*
-	 * Allocate buffers for both outputs. If an output is active, prepare
-	 * for buffer import, otherwise allocate internal buffers. Use the same
-	 * number of buffers in either case.
+	 * Import buffers for all outputs, regardless of whether the
+	 * corresponding stream is active or inactive, as the driver needs
+	 * buffers to be requested on the V4L2 devices in order to operate.
 	 */
-	if (outStream->active_)
-		ret = output_.dev->importBuffers(bufferCount);
-	else
-		ret = output_.dev->allocateBuffers(bufferCount,
-						   &output_.buffers);
+	ret = output_.dev->importBuffers(bufferCount);
 	if (ret < 0) {
-		LOG(IPU3, Error) << "Failed to allocate ImgU output buffers";
+		LOG(IPU3, Error) << "Failed to import ImgU output buffers";
 		goto error;
 	}
 
-	if (vfStream->active_)
-		ret = viewfinder_.dev->importBuffers(bufferCount);
-	else
-		ret = viewfinder_.dev->allocateBuffers(bufferCount,
-						       &viewfinder_.buffers);
+	ret = viewfinder_.dev->importBuffers(bufferCount);
 	if (ret < 0) {
-		LOG(IPU3, Error) << "Failed to allocate ImgU viewfinder buffers";
+		LOG(IPU3, Error) << "Failed to import ImgU viewfinder buffers";
 		goto error;
 	}
 
-- 
2.27.0