ioctl MEDIA_IOC_ENUM_ENTITIES &manvol; MEDIA_IOC_ENUM_ENTITIES Enumerate entities and their properties int ioctl int fd int request struct media_entity_desc *argp fd File descriptor returned by open(). request MEDIA_IOC_ENUM_ENTITIES argp To query the attributes of an entity, applications set the id field of a &media-entity-desc; structure and call the MEDIA_IOC_ENUM_ENTITIES ioctl with a pointer to this structure. The driver fills the rest of the structure or returns an &EINVAL; when the id is invalid. Entities can be enumerated by or'ing the id with the MEDIA_ENT_ID_FLAG_NEXT flag. The driver will return information about the entity with the smallest id strictly larger than the requested one ('next entity'), or the &EINVAL; if there is none. Entity IDs can be non-contiguous. Applications must not try to enumerate entities by calling MEDIA_IOC_ENUM_ENTITIES with increasing id's until they get an error. Two or more entities that share a common non-zero group_id value are considered as logically grouped. Groups are used to report ALSA, VBI and video nodes that carry the same media stream lens and flash controllers associated with a sensor __u32 id Entity id, set by the application. When the id is or'ed with MEDIA_ENT_ID_FLAG_NEXT, the driver clears the flag and returns the first entity with a larger id. char name[32] Entity name as an UTF-8 NULL-terminated string. __u32 type Entity type, see for details. __u32 revision Entity revision in a driver/hardware specific format. __u32 flags Entity flags, see for details. __u32 group_id Entity group ID __u16 pads Number of pads __u16 links Total number of outbound links. Inbound links are not counted in this field. union struct dev Valid for (sub-)devices that create a single device node. __u32 major Device node major number. __u32 minor Device node minor number. __u8 raw[184] MEDIA_ENT_T_DEVNODE Unknown device node MEDIA_ENT_T_DEVNODE_V4L V4L video, radio or vbi device node MEDIA_ENT_T_DEVNODE_FB Frame buffer device node MEDIA_ENT_T_DEVNODE_ALSA ALSA card MEDIA_ENT_T_DEVNODE_DVB_FE DVB frontend devnode MEDIA_ENT_T_DEVNODE_DVB_DEMUX DVB demux devnode MEDIA_ENT_T_DEVNODE_DVB_DVR DVB DVR devnode MEDIA_ENT_T_DEVNODE_DVB_CA DVB CAM devnode MEDIA_ENT_T_DEVNODE_DVB_NET DVB network devnode MEDIA_ENT_T_V4L2_SUBDEV Unknown V4L sub-device MEDIA_ENT_T_V4L2_SUBDEV_SENSOR Video sensor MEDIA_ENT_T_V4L2_SUBDEV_FLASH Flash controller MEDIA_ENT_T_V4L2_SUBDEV_LENS Lens controller MEDIA_ENT_T_V4L2_SUBDEV_DECODER Video decoder, the basic function of the video decoder is to accept analogue video from a wide variety of sources such as broadcast, DVD players, cameras and video cassette recorders, in either NTSC, PAL or HD format and still occasionally SECAM, separate it into its component parts, luminance and chrominance, and output it in some digital video standard, with appropriate embedded timing signals. MEDIA_ENT_T_V4L2_SUBDEV_TUNER TV and/or radio tuner MEDIA_ENT_FL_DEFAULT Default entity for its type. Used to discover the default audio, VBI and video devices, the default camera sensor, ... &return-value; EINVAL The &media-entity-desc; id references a non-existing entity.