From c64f7eb5c038b00c875f77fef56d96f5d4e0866d Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Thu, 2 Sep 2021 04:09:18 +0300 Subject: libcamera: v4l2_videodevice: Split planes when dequeuing buffer When dequeueing a buffer from a V4L2VideoDevice, the number of planes in the FrameBuffer may not match the number of V4L2 buffer planes if the PixelFormat is multi-planar (has multiple colour planes) and the V4L2 format is single-planar (has a single buffer plane). In this case, we need to split the single V4L2 buffer plane into FrameBuffer planes. Do so, and add checks to reject invalid V4L2 buffers in case of a driver issue. Signed-off-by: Laurent Pinchart Reviewed-by: Kieran Bingham Reviewed-by: Hirokazu Honda --- src/libcamera/v4l2_videodevice.cpp | 53 ++++++++++++++++++++++++++++++++++---- 1 file changed, 48 insertions(+), 5 deletions(-) diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp index 6c1ca9bb..2e458fcc 100644 --- a/src/libcamera/v4l2_videodevice.cpp +++ b/src/libcamera/v4l2_videodevice.cpp @@ -7,6 +7,7 @@ #include "libcamera/internal/v4l2_videodevice.h" +#include #include #include #include @@ -1669,12 +1670,54 @@ FrameBuffer *V4L2VideoDevice::dequeueBuffer() buffer->metadata_.timestamp = buf.timestamp.tv_sec * 1000000000ULL + buf.timestamp.tv_usec * 1000ULL; - buffer->metadata_.planes.clear(); - if (multiPlanar) { - for (unsigned int nplane = 0; nplane < buf.length; nplane++) - buffer->metadata_.planes.push_back({ planes[nplane].bytesused }); + if (V4L2_TYPE_IS_OUTPUT(buf.type)) + return buffer; + + unsigned int numV4l2Planes = multiPlanar ? buf.length : 1; + FrameMetadata &metadata = buffer->metadata_; + metadata.planes.clear(); + + if (numV4l2Planes != buffer->planes().size()) { + /* + * If we have a multi-planar buffer with a V4L2 + * single-planar format, split the V4L2 buffer across + * the buffer planes. Only the last plane may have less + * bytes used than its length. + */ + if (numV4l2Planes != 1) { + LOG(V4L2, Error) + << "Invalid number of planes (" << numV4l2Planes + << " != " << buffer->planes().size() << ")"; + + metadata.status = FrameMetadata::FrameError; + return buffer; + } + + unsigned int bytesused = multiPlanar ? planes[0].bytesused + : buf.bytesused; + + for (auto [i, plane] : utils::enumerate(buffer->planes())) { + if (!bytesused) { + LOG(V4L2, Error) + << "Dequeued buffer is too small"; + + metadata.status = FrameMetadata::FrameError; + return buffer; + } + + metadata.planes.push_back({ std::min(plane.length, bytesused) }); + bytesused -= metadata.planes.back().bytesused; + } + } else if (multiPlanar) { + /* + * If we use the multi-planar API, fill in the planes. + * The number of planes in the frame buffer and in the + * V4L2 buffer is guaranteed to be equal at this point. + */ + for (unsigned int i = 0; i < numV4l2Planes; ++i) + metadata.planes.push_back({ planes[i].bytesused }); } else { - buffer->metadata_.planes.push_back({ buf.bytesused }); + metadata.planes.push_back({ buf.bytesused }); } return buffer; -- cgit v1.2.1