[libcamera-devel] [PATCH 04/15] v4l2: v4l2_camera_proxy: Implement VIDIOC_G/S_PRIORITY

[Paul Elder]

Implement VIDIOC_G_PRIORITY and VIDIOC_S_PRIORITY, according to what
v4l2-compliance wants.

Signed-off-by: Paul Elder <paul.elder at ideasonboard.com>
---
 src/v4l2/v4l2_camera_proxy.cpp | 48 +++++++++++++++++++++++++++++++++-
 src/v4l2/v4l2_camera_proxy.h   |  4 +++
 2 files changed, 51 insertions(+), 1 deletion(-)

diff --git a/src/v4l2/v4l2_camera_proxy.cpp b/src/v4l2/v4l2_camera_proxy.cpp
index d899853..f268f7a 100644
--- a/src/v4l2/v4l2_camera_proxy.cpp
+++ b/src/v4l2/v4l2_camera_proxy.cpp
@@ -34,7 +34,7 @@ V4L2CameraProxy::V4L2CameraProxy(unsigned int index,
 				 std::shared_ptr<Camera> camera)
 	: refcount_(0), index_(index), bufferCount_(0), currentBuf_(0),
 	  vcam_(std::make_unique<V4L2Camera>(camera)), efd_(-1),
-	  acquiredFd_(-1), initialized_(false)
+	  v4l2RecordPriorityFd_(-1), acquiredFd_(-1), initialized_(false)
 {
 	querycap(camera);
 }
@@ -44,6 +44,7 @@ int V4L2CameraProxy::open(int fd, bool nonBlocking)
 	LOG(V4L2Compat, Debug) << "Servicing open fd = " << fd;
 
 	nonBlockingFds_[fd] = nonBlocking;
+	priorities_[fd] = V4L2_PRIORITY_DEFAULT;
 
 	refcount_++;
 
@@ -77,6 +78,7 @@ int V4L2CameraProxy::open(int fd, bool nonBlocking)
 void V4L2CameraProxy::dup(int oldfd, int newfd)
 {
 	nonBlockingFds_[newfd] = nonBlockingFds_[oldfd];
+	priorities_[newfd] = V4L2_PRIORITY_DEFAULT;
 	refcount_++;
 }
 
@@ -85,6 +87,7 @@ void V4L2CameraProxy::close(int fd)
 	LOG(V4L2Compat, Debug) << "Servicing close fd = " << fd;
 
 	nonBlockingFds_.erase(fd);
+	priorities_.erase(fd);
 
 	if (acquiredFd_ == fd)
 		acquiredFd_ = -1;
@@ -357,6 +360,43 @@ int V4L2CameraProxy::vidioc_try_fmt(int fd, struct v4l2_format *arg)
 	return 0;
 }
 
+int V4L2CameraProxy::vidioc_g_priority(int fd, enum v4l2_priority *arg)
+{
+	LOG(V4L2Compat, Debug) << "Servicing vidioc_g_priority fd = " << fd;
+
+	if (arg == nullptr)
+		return -EFAULT;
+
+	if (v4l2RecordPriorityFd_ != -1)
+		*arg = V4L2_PRIORITY_RECORD;
+	else
+		*arg = priorities_[fd];
+
+	return 0;
+}
+
+int V4L2CameraProxy::vidioc_s_priority(int fd, enum v4l2_priority *arg)
+{
+	LOG(V4L2Compat, Debug)
+		<< "Servicing vidioc_s_priority fd = " << fd
+		<< " prio =  " << ((arg == nullptr) ? -1 : (int)*arg);
+
+	if (arg == nullptr)
+		return -EFAULT;
+
+	if (v4l2RecordPriorityFd_ != -1 && v4l2RecordPriorityFd_ != fd)
+		return -EBUSY;
+
+	if (*arg == V4L2_PRIORITY_RECORD)
+		v4l2RecordPriorityFd_ = fd;
+	else if (v4l2RecordPriorityFd_ == fd)
+		v4l2RecordPriorityFd_ = -1;
+
+	priorities_[fd] = *arg;
+
+	return 0;
+}
+
 int V4L2CameraProxy::freeBuffers()
 {
 	LOG(V4L2Compat, Debug) << "Freeing libcamera bufs";
@@ -603,6 +643,12 @@ int V4L2CameraProxy::ioctl(int fd, unsigned long request, void *arg)
 	case VIDIOC_TRY_FMT:
 		ret = vidioc_try_fmt(fd, static_cast<struct v4l2_format *>(arg));
 		break;
+	case VIDIOC_G_PRIORITY:
+		ret = vidioc_g_priority(fd, static_cast<enum v4l2_priority *>(arg));
+		break;
+	case VIDIOC_S_PRIORITY:
+		ret = vidioc_s_priority(fd, static_cast<enum v4l2_priority *>(arg));
+		break;
 	case VIDIOC_REQBUFS:
 		ret = vidioc_reqbufs(fd, static_cast<struct v4l2_requestbuffers *>(arg));
 		break;
diff --git a/src/v4l2/v4l2_camera_proxy.h b/src/v4l2/v4l2_camera_proxy.h
index 90e518c..a0c373d 100644
--- a/src/v4l2/v4l2_camera_proxy.h
+++ b/src/v4l2/v4l2_camera_proxy.h
@@ -49,6 +49,8 @@ private:
 	int vidioc_g_fmt(int fd, struct v4l2_format *arg);
 	int vidioc_s_fmt(int fd, struct v4l2_format *arg);
 	int vidioc_try_fmt(int fd, struct v4l2_format *arg);
+	int vidioc_g_priority(int fd, enum v4l2_priority *arg);
+	int vidioc_s_priority(int fd, enum v4l2_priority *arg);
 	int vidioc_reqbufs(int fd, struct v4l2_requestbuffers *arg);
 	int vidioc_querybuf(int fd, struct v4l2_buffer *arg);
 	int vidioc_qbuf(int fd, struct v4l2_buffer *arg);
@@ -84,6 +86,8 @@ private:
 	int efd_;
 
 	std::map<int, bool> nonBlockingFds_;
+	std::map<int, enum v4l2_priority> priorities_;
+	int v4l2RecordPriorityFd_;
 	/*
 	 * This is an exclusive lock on the camera. When this is not taken,
 	 * anybody can call any ioctl before reqbufs. reqbufs with count > 0
-- 
2.27.0