diff --git a/src/libcamera/include/media_device.h b/src/libcamera/include/media_device.h index 3fcdb4b4d5f8..8d491a87867c 100644 --- a/src/libcamera/include/media_device.h +++ b/src/libcamera/include/media_device.h @@ -54,6 +54,8 @@ private: std::vector entities_; + struct media_v2_interface *findInterface(const struct media_v2_topology &topology, + unsigned int entityId); bool populateEntities(const struct media_v2_topology &topology); bool populatePads(const struct media_v2_topology &topology); bool populateLinks(const struct media_v2_topology &topology); diff --git a/src/libcamera/include/media_object.h b/src/libcamera/include/media_object.h index 65b55085a3b0..950a33286690 100644 --- a/src/libcamera/include/media_object.h +++ b/src/libcamera/include/media_object.h @@ -80,21 +80,28 @@ class MediaEntity : public MediaObject { public: const std::string &name() const { return name_; } + unsigned int major() const { return major_; } + unsigned int minor() const { return minor_; } const std::vector &pads() const { return pads_; } const MediaPad *getPadByIndex(unsigned int index) const; const MediaPad *getPadById(unsigned int id) const; + int setDeviceNode(const std::string &devnode); + private: friend class MediaDevice; - MediaEntity(const struct media_v2_entity *entity); + MediaEntity(const struct media_v2_entity *entity, + unsigned int major = 0, unsigned int minor = 0); MediaEntity(const MediaEntity &) = delete; ~MediaEntity(); std::string name_; std::string devnode_; + unsigned int major_; + unsigned int minor_; std::vector pads_; diff --git a/src/libcamera/media_device.cpp b/src/libcamera/media_device.cpp index 605e504be124..70b3fff3f492 100644 --- a/src/libcamera/media_device.cpp +++ b/src/libcamera/media_device.cpp @@ -208,6 +208,7 @@ int MediaDevice::populate() struct media_v2_entity *ents = nullptr; struct media_v2_link *links = nullptr; struct media_v2_pad *pads = nullptr; + struct media_v2_interface *interfaces = nullptr; __u64 version = -1; int ret; @@ -221,6 +222,7 @@ int MediaDevice::populate() topology.ptr_entities = reinterpret_cast<__u64>(ents); topology.ptr_links = reinterpret_cast<__u64>(links); topology.ptr_pads = reinterpret_cast<__u64>(pads); + topology.ptr_interfaces = reinterpret_cast<__u64>(interfaces); ret = ioctl(fd_, MEDIA_IOC_G_TOPOLOGY, &topology); if (ret < 0) { @@ -236,10 +238,12 @@ int MediaDevice::populate() delete[] links; delete[] ents; delete[] pads; + delete[] interfaces; ents = new media_v2_entity[topology.num_entities]; links = new media_v2_link[topology.num_links]; pads = new media_v2_pad[topology.num_pads]; + interfaces = new media_v2_interface[topology.num_interfaces]; version = topology.topology_version; } @@ -253,6 +257,7 @@ int MediaDevice::populate() delete[] links; delete[] ents; delete[] pads; + delete[] interfaces; if (!valid_) { clear(); @@ -367,6 +372,45 @@ void MediaDevice::clear() * \brief Global list of media entities in the media graph */ +/** + * \brief Find the interface associated with an entity + * \param topology The media topology as returned by MEDIA_IOC_G_TOPOLOGY + * \param entityId The entity id + * \return A pointer to the interface if found, or nullptr otherwise + */ +struct media_v2_interface *MediaDevice::findInterface(const struct media_v2_topology &topology, + unsigned int entityId) +{ + struct media_v2_link *links = reinterpret_cast + (topology.ptr_links); + unsigned int ifaceId = -1; + + for (unsigned int i = 0; i < topology.num_links; ++i) { + /* Search for the interface to entity link. */ + if (links[i].sink_id != entityId) + continue; + + if ((links[i].flags & MEDIA_LNK_FL_LINK_TYPE) != + MEDIA_LNK_FL_INTERFACE_LINK) + continue; + + ifaceId = links[i].source_id; + } + + if (ifaceId == static_cast(-1)) + return nullptr; + + struct media_v2_interface *ifaces = reinterpret_cast + (topology.ptr_interfaces); + + for (unsigned int i = 0; i < topology.num_interfaces; ++i) { + if (ifaces[i].id == ifaceId) + return &ifaces[i]; + } + + return nullptr; +} + /* * For each entity in the media graph create a MediaEntity and store a * reference in the media device objects map and entities list. @@ -377,7 +421,26 @@ bool MediaDevice::populateEntities(const struct media_v2_topology &topology) (topology.ptr_entities); for (unsigned int i = 0; i < topology.num_entities; ++i) { - MediaEntity *entity = new MediaEntity(&mediaEntities[i]); + /* + * Find the interface linked to this entity to get the device + * node major and minor numbers. + */ + struct media_v2_interface *iface = + findInterface(topology, mediaEntities[i].id); + if (!iface) { + LOG(Error) << "Failed to find interface link for " + << "entity with id: " << mediaEntities[i].id; + return false; + } + + MediaEntity *entity; + if (iface) + entity = new MediaEntity(&mediaEntities[i], + iface->devnode.major, + iface->devnode.minor); + else + entity = new MediaEntity(&mediaEntities[i]); + if (!addObject(entity)) { delete entity; return false; diff --git a/src/libcamera/media_object.cpp b/src/libcamera/media_object.cpp index b64dcc3c8fb4..69e5cc74264d 100644 --- a/src/libcamera/media_object.cpp +++ b/src/libcamera/media_object.cpp @@ -6,9 +6,8 @@ */ #include -#include #include -#include +#include #include #include @@ -212,6 +211,20 @@ void MediaPad::addLink(MediaLink *link) * \return The entity name */ +/** + * \fn MediaEntity::major() + * \brief Retrieve the major number of the interface associated with the entity + * \return The interface major number, or 0 if the entity isn't associated with + * an interface + */ + +/** + * \fn MediaEntity::minor() + * \brief Retrieve the minor number of the interface associated with the entity + * \return The interface minor number, or 0 if the entity isn't associated with + * an interface + */ + /** * \fn MediaEntity::pads() * \brief Retrieve all pads of the entity @@ -238,6 +251,7 @@ const MediaPad *MediaEntity::getPadByIndex(unsigned int index) const * \param id The pad id * \return The pad identified by \a id, or nullptr if no such pad exist */ + const MediaPad *MediaEntity::getPadById(unsigned int id) const { for (MediaPad *p : pads_) { @@ -248,12 +262,36 @@ const MediaPad *MediaEntity::getPadById(unsigned int id) const return nullptr; } +/** + * \brief Set the path to the device node for the associated interface + * \param devnode The interface device node path associated with this entity + * \return 0 on success, or a negative error code if the device node can't be + * accessed + */ +int MediaEntity::setDeviceNode(const std::string &devnode) +{ + /* Make sure the device node can be accessed. */ + int ret = ::access(devnode.c_str(), R_OK | W_OK); + if (ret < 0) { + ret = -errno; + LOG(Error) << "Device node " << devnode << " can't be accessed: " + << strerror(-ret); + return ret; + } + + return 0; +} + /** * \brief Construct a MediaEntity * \param entity The media entity kernel data + * \param major The major number of the entity associated interface + * \param minor The minor number of the entity associated interface */ -MediaEntity::MediaEntity(const struct media_v2_entity *entity) - : MediaObject(entity->id), name_(entity->name) +MediaEntity::MediaEntity(const struct media_v2_entity *entity, + unsigned int major, unsigned int minor) + : MediaObject(entity->id), name_(entity->name), + major_(major), minor_(minor) { }