NAME
BLUETOOTH
- Bluetooth Device/Protocol API
SYNOPSIS
struct
hci_unit
*
hci_attach(
const struct hci_if *hci_if
, device_t dev
, uint16_t flags
)
void
hci_detach(
struct hci_unit *unit
)
void
hci_input_event(
struct hci_unit *unit
, struct mbuf *m
)
void
hci_input_acl(
struct hci_unit *unit
, struct mbuf *m
)
void
hci_input_sco(
struct hci_unit *unit
, struct mbuf *m
)
int
btproto_attach(
btproto_handle *
, const struct btproto *proto
, void *ref
)
int
btproto_bind(
btproto_handle
, struct sockaddr_bt *addr
)
int
btproto_sockaddr(
btproto_handle
, struct sockaddr_bt *addr
)
int
btproto_connect(
btproto_handle
, struct sockaddr_bt *addr
)
int
btproto_peeraddr(
btproto_handle
, struct sockaddr_bt *addr
)
int
btproto_disconnect(
btproto_handle
, int linger
)
int
btproto_detach(
btproto_handle *
)
int
btproto_listen(
btproto_handle
)
int
btproto_send(
btproto_handle
, struct mbuf *mbuf
)
int
btproto_rcvd(
btproto_handle
, size_t space
)
int
btproto_setopt(
btproto_handle
, int optarg
, void *arg
)
int
btproto_getopt(
btproto_handle
, int optarg
, void *arg
)
DESCRIPTION
The Bluetooth Protocol Stack provides socket based access to Bluetooth
Devices.
This document describes device driver access to the stack from
below, and also the general Bluetooth Protocol/Service API for layering
above existing Bluetooth Protocols.
DATA TYPES
Device drivers attaching to the Bluetooth Protocol Stack should pass a
pointer to a
struct
hci_if
defined in
containing the driver information as follows:
struct hci_if {
int (*enable)(device_t);
void (*disable)(device_t);
void (*output_cmd)(device_t, struct mbuf *);
void (*output_acl)(device_t, struct mbuf *);
void (*output_sco)(device_t, struct mbuf *);
void (*get_stats)(device_t, struct bt_stats *, int);
int ipl;
};
Statistics counters should be updated by the device after packets have
been transmitted or received, or when errors occur.
struct bt_stats {
uint32_t err_tx;
uint32_t err_rx;
uint32_t cmd_tx;
uint32_t evt_rx;
uint32_t acl_tx;
uint32_t acl_rx;
uint32_t sco_tx;
uint32_t sco_rx;
uint32_t byte_tx;
uint32_t byte_rx;
};
Bluetooth Protocol layers attaching above the Bluetooth Protocol Stack
will make use of the
struct
btproto
data type, which is defined in
and contains the following function callbacks which
should be initialized by the protocol layer before attaching to the
protocol which it uses:
struct btproto {
void (*connecting)(void *);
void (*connected)(void *);
void (*disconnected)(void *, int);
void *(*newconn)(void *, struct sockaddr_bt *, struct sockaddr_bt *);
void (*complete)(void *, int);
void (*linkmode)(void *, int);
void (*input)(void *, struct mbuf *);
};
FUNCTIONS
The following functions are related to the Bluetooth Device API.
- hci_attach(
hci_if
, dev
) -
Attach Bluetooth HCI device
dev
to the protocol stack in the manner described by
hci_if.
Driver quirks may be registered by passing the corresponding
BTF_xxxx
flag in the
flags
argument.
hci_attach(
)
will return a
struct
hci_unit
handle to be passed to the protocol stack in other calls.
- hci_detach(
unit
) -
Detach Bluetooth HCI
unit
from the device.
- hci_input_event(
unit
, mbuf
) -
This function should be called by the device when it has an event
packet to present to the protocol stack.
It may be called from an interrupt routine at the
ipl
value given in the
hci_if
descriptor.
- hci_input_acl(
unit
, mbuf
) -
This function should be called by the device when it has an ACL data
packet to present to the protocol stack.
It may be called from an interrupt routine at the
ipl
value given in the
hci_if
descriptor.
- hci_input_sco(
unit
, mbuf
) -
This function should be called by the device when it has an SCO data
packet to present to the protocol stack.
It may be called from an interrupt routine at the
ipl
value given in the
hci_if
descriptor.
- (*enable)(
dev
) -
This will be called when the protocol stack wishes to enable the device.
- (*disable)(
dev
) -
This will be called when the protocol stack wishes to disable the device.
- (*output_cmd)(
dev
, mbuf
) -
Will be called to output command packets on the device.
The device is responsible for arbitrating access to the output queue, and
output commands should be sent asynchronously.
The device owns the
mbuf
and should release it when sent.
- (*output_acl)(
dev
, mbuf
) -
Will be called to output ACL data packets on the device.
The device is responsible for arbitrating access to the output queue, and
ACL data packets should be sent asynchronously.
The device owns the
mbuf
and should release it when sent.
- (*output_sco)(
dev
, mbuf
) -
Will be called to output SCO data packets on the device.
The device is responsible for arbitrating access to the output queue, and
SCO data packets should be sent asynchronously.
When the SCO data packet has been placed on the device and the
mbuf
is no longer required, it should be returned to the Bluetooth protocol
stack via the
hci_complete_sco(
)
call.
- (*get_stats)(
dev
, dest
, flush
) -
Will be called when IO statistics are requested.
The
bt_stats
structure
dest
should be filled in, and if the
flush
argument is true, statistics should be reset.
The following function definitions are related to the Bluetooth Protocol API.
Note that the "btproto" prefix is representative only, the protocol being
used will have a more specific prefix with prototypes being declared in
the appropriate
file.
- btproto_attach(
handle_ptr
, proto
, ref
) -
Allocate and initialize a new protocol object at the
handle_ptr
address that should subsequently be passed into the other functions.
proto
is a pointer to the
btproto
structure as described above containing relevant callbacks, and
ref
is the argument that will be supplied to those calls.
- btproto_bind(
handle
, addr
) -
Set the local address of the protocol object described by
handle
to
addr.
- btproto_sockaddr(
handle
, addr
) -
Copy the local address of the protocol object described by
handle
into
addr
- btproto_connect(
handle
, addr
) -
Initiate a connection by the protocol object described by
handle
to the remote device described by
addr.
This will result in a call to either
proto->connected(
)
or
proto->disconnected(
),
and optionally
proto->connecting(
)
with the appropriate reference as given to
btproto_attach(
).
- btproto_peeraddr(
handle
, addr
) -
Copy the remote address of the protocol object described by
handle
into
addr.
- btproto_disconnect(
handle
, linger
) -
Schedule a disconnection by the protocol object described by
handle.
This will result in a call to
proto->disconnected(
)
with the appropriate reference when the connection is torn
down.
If linger is zero, the disconnection will be initiated
immediately and any outstanding data may be lost.
- btproto_detach(
handle_ptr
) -
Detach the protocol object described by the value in the location of
handle_ptr,
and free any related memory.
The pointer in the location is cleared.
- btproto_listen(
handle
) -
Use the protocol object described by
handle
as a listening post.
This will result in calls to the
proto->newconn(
)
function when incoming connections are detected.
- btproto_send(
handle
, mbuf
) -
Send data on the connection described by the protocol object.
- btproto_rcvd(
handle
, space
) -
Indicate to the protocol that
space
is now available in the input buffers so that flow control may be
deasserted.
This should also be called to indicate initial buffer space.
Note that
space
is an absolute value.
- btproto_setopt(
handle
, optarg
, arg
) -
Set options on the protocol object described by
handle.
- btproto_getopt(
handle
, optarg
, arg
) -
Get options for the protocol object described by
handle.
- (*connecting)(
ref
) -
This function will be called when the protocol receives information
that the connection described by
ref
is pending.
- (*connected)(
ref
) -
This function will be called when the connection described by
ref
is successful and indicates that data may now be sent.
- (*disconnected)(
ref
, error
) -
This function will be called when the connection described by
ref
is disconnected.
- *(*newconn)(
ref
, laddr
, raddr
) -
This function will be called when the protocol receives a new incoming
connection on the local device described by
laddr
from the remote device described by
raddr.
The protocol should decide if it wishes to accept the connection and
should attach and return a new instance of the relevant protocol handle
or NULL.
- (*complete)(
ref
, count
) -
This function will be called when the protocol has completed sending
data.
Complete will usually mean that the data has successfully left
the device though for guaranteed protocols it can mean that the data
has arrived at the other end and been acknowledged, and that
count
amount of data can be removed from the socket buffer.
The units of the
count
value will be dependent on the protocol being used (e.g. RFCOMM is bytes,
but L2CAP is packets)
- (*linkmode)(
ref
, mode
) -
This function will be called for established connections, when the link mode
of the baseband link has changed.
mode
is the new mode.
- (*input)(
ref
, mbuf
) -
This function is called to supply new data on the connection described by
ref.
CODE REFERENCES
This section describes places in the
NetBSD
source tree where actual code implementing or using the
Bluetooth Protocol Stack can be found.
All pathnames are relative to
/usr/src
.
The Bluetooth Protocol Stack is contained in the
sys/netbt
directory.
The Bluetooth Device API as described above is contained
in the
sys/netbt/hci_unit.c
file.
For examples of the Bluetooth Protocol API see the interaction between
the L2CAP upper layer in
sys/netbt/l2cap_upper.c
and either the L2CAP socket layer in
sys/netbt/l2cap_socket.c
or the
bthidev(4)
pseudo-device in
sys/dev/bluetooth/bthidev.c
.
Also, the RFCOMM upper layer in
sys/netbt/rfcomm_upper.c
and the RFCOMM socket layer in
sys/netbt/rfcomm_socket.c
.
SEE ALSO
bluetooth(4),
bt3c(4),
bthidev(4),
ubt(4)
HISTORY
This Bluetooth Protocol Stack was written for
NetBSD4.0
by
Iain Hibbert
,
under the sponsorship of Itronix, Inc.