Bluetooth: Coordinated Set Identification Profile
This document describes how to run the coordinated set identification functionality, both as a client and as a server. Note that in the examples below, some lines of debug have been removed to make this shorter and provide a better overview.
Set Coordinator (Client)
The client will typically be a resource-rich device, such as a smartphone or a laptop. The client is able to lock and release members of a coordinated set. While the coordinated set is locked, no other clients may lock the set.
To lock a set, the client must connect to each of the set members it wants to
lock. This implementation will always try to connect to all the members of
the set, and at the same time. Thus if the set size is 3, then
BT_MAX_CONN shall be at least 3.
If the locks on set members shall persists through disconnects, it is
necessary to bond with the set members. If you need to bond with multiple
set members, make sure that BT_MAX_PAIRED is correctly configured.
Using the Set Coordinator
When the Bluetooth stack has been initialized (bt init),
and a set member device has been connected, the call control client can be
initialized by calling csip_set_coordinator init, which will start a discovery
for the TBS uuids and store the handles, and optionally subscribe to all
notifications (default is to subscribe to all).
Once the client has connected and discovered the handles, then it can read the set information, which is needed to identify other set members. The client can then scan for and connect to the remaining set members, and once all the members has been connected to, it can lock and release the set.
It is necessary to enable
CONFIG_BT_CSIP_SET_COORDINATOR_LOG_LEVEL_DBG to properly use
the set coordinator.
csip_set_coordinator --help
csip_set_coordinator - Bluetooth CSIP_SET_COORDINATOR shell commands
Subcommands:
init :Initialize CSIP_SET_COORDINATOR
discover :Run discover for CSIS on peer device [member_index]
discover_members :Scan for set members <set_pointer>
lock_set :Lock set
release_set :Release set
lock :Lock specific member [member_index]
release :Release specific member [member_index]
lock_get :Get the lock value of the specific member and instance
[member_index [inst_idx]]
Example usage
Setup
uart:~$ init
uart:~$ bt connect xx:xx:xx:xx:xx:xx public
When connected
Discovering sets on a device:
uart:~$ csip_set_coordinator init
<dbg> bt_csip_set_coordinator.primary_discover_func: [ATTRIBUTE] handle 0x0048
<dbg> bt_csip_set_coordinator.primary_discover_func: Discover complete, found 1 instances
<dbg> bt_csip_set_coordinator.discover_func: Setup complete for 1 / 1
Found 1 sets on device
uart:~$ csip_set_coordinator discover_sets
<dbg> bt_csip_set_coordinator.SIRK
36 04 9a dc 66 3a a1 a1 |6...f:..
1d 9a 2f 41 01 73 3e 01 |../A.s>.
<dbg> bt_csip_set_coordinator.csip_set_coordinator_discover_sets_read_set_size_cb: 2
<dbg> bt_csip_set_coordinator.csip_set_coordinator_discover_sets_read_set_lock_cb: 1
<dbg> bt_csip_set_coordinator.csip_set_coordinator_discover_sets_read_rank_cb: 1
Set size 2 (pointer: 0x566fdfe8)
Discover set members, based on the set pointer above:
uart:~$ csip_set_coordinator discover_members 0x566fdfe8
<dbg> bt_csip_set_coordinator.csip_found: Found CSIS advertiser with address 34:02:86:03:86:c0 (public)
<dbg> bt_csip_set_coordinator.is_set_member: hash: 0x33ccb1, prand 0x5bfe6a
<dbg> bt_csip_set_coordinator.is_discovered: 34:02:86:03:86:c0 (public)
<dbg> bt_csip_set_coordinator.is_discovered: 34:13:e8:b3:7f:9e (public)
<dbg> bt_csip_set_coordinator.csip_found: Found member (2 / 2)
Discovered 2/2 set members
Lock set members:
uart:~$ csip_set_coordinator lock_set
<dbg> bt_csip_set_coordinator.bt_csip_set_coordinator_lock_set: Connecting to 34:02:86:03:86:c0 (public)
<dbg> bt_csip_set_coordinator.csip_set_coordinator_connected: Connected to 34:02:86:03:86:c0 (public)
<dbg> bt_csip_set_coordinator.discover_func: Setup complete for 1 / 1
<dbg> bt_csip_set_coordinator.csip_set_coordinator_lock_set_init_cb:
<dbg> bt_csip_set_coordinator.SIRK
36 04 9a dc 66 3a a1 a1 |6...f:..
1d 9a 2f 41 01 73 3e 01 |../A.s>.
<dbg> bt_csip_set_coordinator.csip_set_coordinator_discover_sets_read_set_size_cb: 2
<dbg> bt_csip_set_coordinator.csip_set_coordinator_discover_sets_read_set_lock_cb: 1
<dbg> bt_csip_set_coordinator.csip_set_coordinator_discover_sets_read_rank_cb: 2
<dbg> bt_csip_set_coordinator.csip_set_coordinator_write_lowest_rank: Locking member with rank 1
<dbg> bt_csip_set_coordinator.notify_func: Instance 0 lock was locked
<dbg> bt_csip_set_coordinator.csip_set_coordinator_write_lowest_rank: Locking member with rank 2
<dbg> bt_csip_set_coordinator.notify_func: Instance 0 lock was locked
Set locked
Release set members:
uart:~$ csip_set_coordinator release_set
<dbg> bt_csip_set_coordinator.csip_set_coordinator_release_highest_rank: Releasing member with rank 2
<dbg> bt_csip_set_coordinator.notify_func: Instance 0 lock was released
<dbg> bt_csip_set_coordinator.csip_set_coordinator_release_highest_rank: Releasing member with rank 1
<dbg> bt_csip_set_coordinator.notify_func: Instance 0 lock was released
Set released
Coordinated Set Member (Server)
The server on devices that are part of a set, consisting of at least two devices, e.g. a pair of earbuds.
Using the Set Member
csip_set_member --help
csip_set_member - Bluetooth CSIP set member shell commands
Subcommands:
register :Initialize the service and register callbacks [size <int>]
[rank <int>] [not-lockable] [sirk <data>]
lock :Lock the set
release :Release the set [force]
sirk :Set the currently used SIRK <sirk>
get_sirk :Get the currently used SIRK
sirk_rsp :Set the response used in SIRK requests <accept, accept_enc,
reject, oob>
Example Usage
Setup
uart:~$ bt init
uart:~$ csip_set_member register
Setting a new SIRK
This command can modify the currently used SIRK. To get the new RSI to advertise on air,
bt adv-data or bt advertise must be called again to set the new advertising data.
If CONFIG_BT_CSIP_SET_MEMBER_NOTIFIABLE is enabled, this will also notify connected
clients.
uart:~$ csip_set_member sirk 00112233445566778899aabbccddeeff
SIRK updated
Getting the current SIRK
This command can get the currently used SIRK.
uart:~$ csip_set_member get_sirk
SIRK
36 04 9a dc 66 3a a1 a1 |6...f:..
1d 9a 2f 41 01 73 3e 01 |../A.s>.