diff options
| -rw-r--r-- | src/libcamera/include/v4l2_videodevice.h | 8 | ||||
| -rw-r--r-- | src/libcamera/v4l2_videodevice.cpp | 75 |
2 files changed, 82 insertions, 1 deletions
diff --git a/src/libcamera/include/v4l2_videodevice.h b/src/libcamera/include/v4l2_videodevice.h index ee63d28d..a0409e59 100644 --- a/src/libcamera/include/v4l2_videodevice.h +++ b/src/libcamera/include/v4l2_videodevice.h @@ -224,6 +224,9 @@ public: int queueBuffer(FrameBuffer *buffer); Signal<FrameBuffer *> bufferReady; + int setFrameStartEnabled(bool enable); + Signal<uint32_t> frameStart; + int streamOn(); int streamOff(); @@ -262,6 +265,8 @@ private: void bufferAvailable(EventNotifier *notifier); FrameBuffer *dequeueBuffer(); + void eventAvailable(EventNotifier *notifier); + V4L2Capability caps_; enum v4l2_buf_type bufferType_; @@ -271,6 +276,9 @@ private: std::map<unsigned int, FrameBuffer *> queuedBuffers_; EventNotifier *fdBufferNotifier_; + EventNotifier *fdEventNotifier_; + + bool frameStartEnabled_; }; class V4L2M2MDevice diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp index fae4f078..8d642be0 100644 --- a/src/libcamera/v4l2_videodevice.cpp +++ b/src/libcamera/v4l2_videodevice.cpp @@ -544,7 +544,8 @@ const std::string V4L2DeviceFormat::toString() const * \param[in] deviceNode The file-system path to the video device node */ V4L2VideoDevice::V4L2VideoDevice(const std::string &deviceNode) - : V4L2Device(deviceNode), cache_(nullptr), fdBufferNotifier_(nullptr) + : V4L2Device(deviceNode), cache_(nullptr), fdBufferNotifier_(nullptr), + fdEventNotifier_(nullptr), frameStartEnabled_(false) { /* * We default to an MMAP based CAPTURE video device, however this will @@ -637,6 +638,10 @@ int V4L2VideoDevice::open() fdBufferNotifier_->activated.connect(this, &V4L2VideoDevice::bufferAvailable); fdBufferNotifier_->setEnabled(false); + fdEventNotifier_ = new EventNotifier(fd(), EventNotifier::Exception); + fdEventNotifier_->activated.connect(this, &V4L2VideoDevice::eventAvailable); + fdEventNotifier_->setEnabled(false); + LOG(V4L2, Debug) << "Opened device " << caps_.bus_info() << ": " << caps_.driver() << ": " << caps_.card(); @@ -726,6 +731,10 @@ int V4L2VideoDevice::open(int handle, enum v4l2_buf_type type) fdBufferNotifier_->activated.connect(this, &V4L2VideoDevice::bufferAvailable); fdBufferNotifier_->setEnabled(false); + fdEventNotifier_ = new EventNotifier(fd(), EventNotifier::Exception); + fdEventNotifier_->activated.connect(this, &V4L2VideoDevice::eventAvailable); + fdEventNotifier_->setEnabled(false); + LOG(V4L2, Debug) << "Opened device " << caps_.bus_info() << ": " << caps_.driver() << ": " << caps_.card(); @@ -743,6 +752,7 @@ void V4L2VideoDevice::close() releaseBuffers(); delete fdBufferNotifier_; + delete fdEventNotifier_; V4L2Device::close(); } @@ -1571,11 +1581,74 @@ FrameBuffer *V4L2VideoDevice::dequeueBuffer() } /** + * \brief Slot to handle V4L2 events from the V4L2 video device + * \param[in] notifier The event notifier + * + * When this slot is called, a V4L2 event is available to be dequeued from the + * device. + */ +void V4L2VideoDevice::eventAvailable(EventNotifier *notifier) +{ + struct v4l2_event event{}; + int ret = ioctl(VIDIOC_DQEVENT, &event); + if (ret < 0) { + LOG(V4L2, Error) + << "Failed to dequeue event, disabling event notifier"; + fdEventNotifier_->setEnabled(false); + return; + } + + if (event.type != V4L2_EVENT_FRAME_SYNC) { + LOG(V4L2, Error) + << "Spurious event (" << event.type + << "), disabling event notifier"; + fdEventNotifier_->setEnabled(false); + return; + } + + frameStart.emit(event.u.frame_sync.frame_sequence); +} + +/** * \var V4L2VideoDevice::bufferReady * \brief A Signal emitted when a framebuffer completes */ /** + * \brief Enable or disable frame start event notification + * \param[in] enable True to enable frame start events, false to disable them + * + * This function enables or disables generation of frame start events. Once + * enabled, the events are signalled through the frameStart signal. + * + * \return 0 on success, a negative error code otherwise + */ +int V4L2VideoDevice::setFrameStartEnabled(bool enable) +{ + if (frameStartEnabled_ == enable) + return 0; + + struct v4l2_event_subscription event{}; + event.type = V4L2_EVENT_FRAME_SYNC; + + unsigned long request = enable ? VIDIOC_SUBSCRIBE_EVENT + : VIDIOC_UNSUBSCRIBE_EVENT; + int ret = ioctl(request, &event); + if (enable && ret) + return ret; + + fdEventNotifier_->setEnabled(enable); + frameStartEnabled_ = enable; + + return ret; +} + +/** + * \var V4L2VideoDevice::frameStart + * \brief A Signal emitted when capture of a frame has started + */ + +/** * \brief Start the video stream * \return 0 on success or a negative error code otherwise */ |