From 677cb4bfc23e7fd8f49d2d10af64f171942fab84 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Sat, 12 Dec 2015 10:56:13 -0200 Subject: [media] DocBook: Document MEDIA_IOC_G_TOPOLOGY Add description for this new media controller ioctl. Signed-off-by: Mauro Carvalho Chehab --- .../DocBook/media/v4l/media-controller.xml | 1 + .../DocBook/media/v4l/media-ioc-g-topology.xml | 391 +++++++++++++++++++++ 2 files changed, 392 insertions(+) create mode 100644 Documentation/DocBook/media/v4l/media-ioc-g-topology.xml (limited to 'Documentation/DocBook/media') diff --git a/Documentation/DocBook/media/v4l/media-controller.xml b/Documentation/DocBook/media/v4l/media-controller.xml index 63d48decaa6f..5f2fc07a93d7 100644 --- a/Documentation/DocBook/media/v4l/media-controller.xml +++ b/Documentation/DocBook/media/v4l/media-controller.xml @@ -98,6 +98,7 @@ &sub-media-func-ioctl; &sub-media-ioc-device-info; + &sub-media-ioc-g-topology; &sub-media-ioc-enum-entities; &sub-media-ioc-enum-links; &sub-media-ioc-setup-link; diff --git a/Documentation/DocBook/media/v4l/media-ioc-g-topology.xml b/Documentation/DocBook/media/v4l/media-ioc-g-topology.xml new file mode 100644 index 000000000000..e0d49fa329f0 --- /dev/null +++ b/Documentation/DocBook/media/v4l/media-ioc-g-topology.xml @@ -0,0 +1,391 @@ + + + ioctl MEDIA_IOC_G_TOPOLOGY + &manvol; + + + + MEDIA_IOC_G_TOPOLOGY + Enumerate the graph topology and graph element properties + + + + + + int ioctl + int fd + int request + struct media_v2_topology *argp + + + + + + Arguments + + + + fd + + File descriptor returned by + open(). + + + + request + + MEDIA_IOC_G_TOPOLOGY + + + + argp + + + + + + + + + Description + The typical usage of this ioctl is to call it twice. + On the first call, the structure defined at &media-v2-topology; should + be zeroed. At return, if no errors happen, this ioctl will return the + topology_version and the total number of entities, + interfaces, pads and links. + Before the second call, the userspace should allocate arrays to + store the graph elements that are desired, putting the pointers to them + at the ptr_entities, ptr_interfaces, ptr_links and/or ptr_pads, keeping + the other values untouched. + If the topology_version remains the same, the + ioctl should fill the desired arrays with the media graph elements. + + + struct <structname>media_v2_topology</structname> + + + + + + + + + __u64 + topology_version + + + Version of the media graph topology. When the graph is + created, this field starts with zero. Every time a graph + element is added or removed, this field is + incremented. + + + __u64 + num_entities + + + Number of entities in the graph + + + __u64 + ptr_entities + + + A pointer to a memory area where the entities array + will be stored, converted to a 64-bits integer. + It can be zero. if zero, the ioctl won't store the + entities. It will just update + num_entities + + + __u64 + num_interfaces + + + Number of interfaces in the graph + + + __u64 + ptr_interfaces + + + A pointer to a memory area where the interfaces array + will be stored, converted to a 64-bits integer. + It can be zero. if zero, the ioctl won't store the + interfaces. It will just update + num_interfaces + + + __u64 + num_pads + + + Total number of pads in the graph + + + __u64 + ptr_pads + + + A pointer to a memory area where the pads array + will be stored, converted to a 64-bits integer. + It can be zero. if zero, the ioctl won't store the + pads. It will just update + num_pads + + + __u64 + num_links + + + Total number of data and interface links in the graph + + + __u64 + ptr_links + + + A pointer to a memory area where the links array + will be stored, converted to a 64-bits integer. + It can be zero. if zero, the ioctl won't store the + links. It will just update + num_links + + + +
+ + + struct <structname>media_v2_entity</structname> + + + + + + + + + __u32 + id + + + Unique ID for the entity. + + + char + name[64] + + + Entity name as an UTF-8 NULL-terminated string. + + + __u32 + function + + + Entity main function, see for details. + + + __u32 + reserved[12] + Reserved for future extensions. Drivers and applications must + set this array to zero. + + + +
+ + + struct <structname>media_v2_interface</structname> + + + + + + + + + __u32 + id + + + Unique ID for the interface. + + + __u32 + intf_type + + + Interface type, see for details. + + + __u32 + flags + + + Interface flags. Currently unused. + + + __u32 + reserved[9] + + + Reserved for future extensions. Drivers and applications must + set this array to zero. + + + struct media_v2_intf_devnode + devnode + + + Used only for device node interfaces. See for details.. + + + +
+ + + struct <structname>media_v2_interface</structname> + + + + + + + + + __u32 + major + + + Device node major number. + + + __u32 + minor + + + Device node minor number. + + + +
+ + + struct <structname>media_v2_pad</structname> + + + + + + + + + __u32 + id + + + Unique ID for the pad. + + + __u32 + entity_id + + + Unique ID for the entity where this pad belongs. + + + __u32 + flags + + + Pad flags, see for more details. + + + __u32 + reserved[9] + + + Reserved for future extensions. Drivers and applications must + set this array to zero. + + + +
+ + + struct <structname>media_v2_pad</structname> + + + + + + + + + __u32 + id + + + Unique ID for the pad. + + + __u32 + source_id + + + + On pad to pad links: unique ID for the source pad. + On interface to entity links: unique ID for the interface. + + + + __u32 + sink_id + + + + On pad to pad links: unique ID for the sink pad. + On interface to entity links: unique ID for the entity. + + + + __u32 + flags + + + Link flags, see for more details. + + + __u32 + reserved[5] + + + Reserved for future extensions. Drivers and applications must + set this array to zero. + + + + + + + + + &return-value; + + + + ENOSPC + + This is returned when either one or more of the num_entities, + num_interfaces, num_links or num_pads are non-zero and are smaller + than the actual number of elements inside the graph. This may happen + if the topology_version changed when compared + to the last time this ioctl was called. Userspace should usually + free the area for the pointers, zero the struct elements and call + this ioctl again. + + + + + -- cgit v1.2.3