fuchsia.bluetooth.hfp

PROTOCOLS

Call

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Controls the lifecycle of a call that has been routed through a headset.

RequestActive

Request that the Call be set to the ONGOING_ACTIVE CallState. This has the side effect of placing all other Calls that are routed to this peer in the ONGOING_HELD call state if it succeeds.

Request

<EMPTY>

RequestHold

Request that the Call be set to the ONGOING_HELD CallState

Request

<EMPTY>

RequestTerminate

Request that the Call be TERMINATED.

Request

<EMPTY>

RequestTransferAudio

Request that the Call's audio be transfered to the Audio Gateway and the call state set to TRANSFERRED_TO_AG.

Request

<EMPTY>

SendDtmfCode

Send a code that the call manager or remote audio gateway peer should transmit to its network connection. The request returns after the code has been transmitted to the network.

Can return an error if the call manager or peer failed to transmit the code to the network.

Request

Name	Type
code	DtmfCode

Response

Name	Type
payload	Call_SendDtmfCode_Result

WatchState

A hanging get method for call state. See the CallState documentation for information on possible states.

Request

<EMPTY>

Response

Name	Type
state	CallState

CallManager

Defined in fuchsia.bluetooth.hfp/hfp.fidl

PeerConnected

Signal that a peer that supports the HFP Hands-Free role is connected.

id is the unique identifier associated with the peer. handle is the channel that the call manager should use to manage a the peer. If the call manager does not intend to handle a given peer, it must close the handle with a ZX_ERR_UNAVAILABLE epitaph.

Multiple concurrent PeerConnected requests can be made by the client. The empty response is used as a flow control mechanism to allow the client to limit the number of pending PeerConnected requests.

Request

Name	Type
id	fuchsia.bluetooth/PeerId
handle	server_end:PeerHandler

Response

<EMPTY>

HandsFree

Defined in fuchsia.bluetooth.hfp/hfp.fidl

WatchPeerConnected

Hanging get that waits for a a peer that supports the HFP Audio Gateway role to connect.

id is the unique identifier associated with the peer.

handle is the channel that the client should use to manage the peer. If the call manager does not intend to handle a given peer. it must close the handle,

Request

<EMPTY>

Response

Name	Type
payload	HandsFree_WatchPeerConnected_Result

HeadsetGain

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Control Headset Speaker and Microphone gain and receive reports of current values as specified in HFP v1.8, Section 4.29. This protocol is served by the Hfp service.

Gain is represented as an absolute value on a scale from 0 to 15. 0 is the minimum gain and 15 is the maximum gain. It is related to a particular (implementation dependent) volume level controlled by the Headset.

Epitaphs:

This channel will be closed with a ZX_ERR_ALREADY_BOUND epitaph if there is already an active HeadsetGain channel.

This channel will be closed with a ZX_ERR_NOT_SUPPORTED epitaph if the Hfp service is not configured to support remote volume control or the peer headset does not support remote volume control. If the channel is closed with this error, the client should not attempt to reopen it using the PeerHandler::GainControl request on the same PeerHandler connection.

This channel will be closed with a ZX_ERR_INVALID_ARGUMENT epitaph if invalid arguments are passed to requests. See documentation on specific requests for more details.

SetMicrophoneGain

Make a request to the Headset to set the microphone gain to requested.

requested must be in the range [0-15] inclusive. Any values outside of this range will result in the channel closing with a ZX_ERR_INVALID_ARGUMENT epitaph.

Request

Name	Type
requested	uint8

SetSpeakerGain

Make a request to the headset to set the speaker gain to requested.

requested must be in the range [0-15] inclusive. Any values outside of this range will result in the channel closing with a ZX_ERR_INVALID_ARGUMENT epitaph.

Request

Name	Type
requested	uint8

WatchMicrophoneGain

Hanging get to watch for updates to the headset microphone gain. Responses represent the current gain value that is set.

The returned gain value will always be in the range [0-15] inclusive.

Request

<EMPTY>

Response

Name	Type
gain	uint8

WatchSpeakerGain

Hanging get to watch for updates to the headset speaker gain. Responses represent the current gain value that is set.

The returned gain value will always be in the range [0-15] inclusive.

Request

<EMPTY>

Response

Name	Type
gain	uint8

Hfp

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Register

Register as the call manager for this device.

There can only be one call manager registered at a time. If one is registered at the time a call to Register is made, the newer CallManager channel will be closed.

A call manager can be unregistered by closing either end of the channel.

Request

Name	Type
manager	client_end:CallManager

PeerHandler

Defined in fuchsia.bluetooth.hfp/hfp.fidl

The call manager or the hands-free server component will serve a call handler protocol for each connected headset that it chooses to manage calls through.

If the peer handler is closed by either channel endpoint, all protocols associated with this peer handler are closed. This includes any Call, and HeadsetGain protocols. Channels closed by a server end will include an epitaph ZX_ERR_HANDLE_CLOSED in this situation.

GainControl

Tear off protocol for Headset Gain.

Only one HeadsetGain protocol can be active for a PeerHandler protocol at any given time. Older HeadsetGain protocols are given preference. If a HeadsetGain protocol is active when a new GainControl request is made, the new HeadsetGain protocol will be closed immediately.

Request

Name	Type
control	client_end:HeadsetGain

QueryOperator

Request the name of the network operator for the call manager or audio gateway peer. A null value is returned if there is no operator name available.

Request

<EMPTY>

Response

Name	Type
operator	string:16?

ReportHeadsetBatteryLevel

Headset battery level from 0 ~ 100 See https://www.bluetooth.com/specifications/assigned-numbers/hands-free-profile/

Request

Name	Type
level	uint8

RequestOutgoingCall

Used to request an outgoing call be initiated by the call manager or audio gateway peer. RequestOutgoingCall shall complete after the outgoing call has been initiated and the corresponding Call protocol has been returned via a WatchNextCall result.

An error is returned if the call could not be placed as requested.

• ZX_ERR_NOT_SUPPORTED can be used if the system does not support the requested action.

• ZX_ERR_ALREADY_EXISTS can be used if there is alreadya call in progress and the system does not support additional calls.

Request

Name	Type
action	CallAction

Response

Name	Type
payload	PeerHandler_RequestOutgoingCall_Result

SetNrecMode

Request by the HF to enable or disable the Noise Reduction/Echo Cancellation functionality on the AG based on the enabled boolean. A ZX_ERR_NOT_SUPPORTED error is returned if Noice Reduction/Echo Cancellation is not supported by the device.

Request

Name	Type
enabled	bool

Response

Name	Type
payload	PeerHandler_SetNrecMode_Result

SubscriberNumberInformation

Request subscriber numbers from the call manager or audio gateway peer. There can be zero or more numbers returned. Sending more than 128 numbers is not supported at this time.

Request

<EMPTY>

Response

Name	Type
numbers	vector<Number>:128

WatchNetworkInformation

Hanging get to provide the Hfp service with an update on the NetworkInformation. Any fields in update that are not present will be treated as unmodified by the update.

The call manager or audio gateway peer should provide a fully populated update when it is called for the first time.

The most up-to-date NetworkInformation is used during the connection initialization process of the peer, and updates are propagated to the peer if it supports AG Indicators.

Request

<EMPTY>

Response

Name	Type
update	NetworkInformation

WatchNextCall

Hanging get which returns when a new call is initiated by the call manager or audio gateway peer, or an ongoing call is transferred to the headset. RequestOutgoingCall can be called before or after WatchNextCall.

Request

<EMPTY>

Response

Name	Type
call	NextCall

STRUCTS

Call_SendDtmfCode_Response

Defined in fuchsia.bluetooth.hfp/hfp.fidl

<EMPTY>

HandsFree_WatchPeerConnected_Response resource

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Field	Type	Description	Default
id	fuchsia.bluetooth/PeerId		No default
handle	client_end:PeerHandler		No default

PeerHandler_RequestOutgoingCall_Response

Defined in fuchsia.bluetooth.hfp/hfp.fidl

<EMPTY>

PeerHandler_SetNrecMode_Response

Defined in fuchsia.bluetooth.hfp/hfp.fidl

<EMPTY>

RedialLast

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Represents the action of redialing the last dialed number.

<EMPTY>

TransferActive

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Represents the action of transferring an active call to the Headset.

<EMPTY>

ENUMS

CallDirection strict

Type: uint32

Defined in fuchsia.bluetooth.hfp/hfp.fidl

The direction of call initiation.

Name	Value	Description
MOBILE_ORIGINATED	1	Call originated on this device. This is also known as an Outgoing call.
MOBILE_TERMINATED	2	Call is terminated on this device. This is also known as an Incoming call.

CallState flexible

Type: uint32

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Represents the valid states of a call.

Name	Value	Description
OUTGOING_DIALING	1	There is a callsetup procedure in progress for an outgoing call. This state should not be set by the Call protocol client. It is the initial state of an unanswered outgoing call.
OUTGOING_ALERTING	2	There is a callsetup procedure in progress for an outgoing call and the remote party has been alerted to the callsetup. This state is an optional transition from OUTGOING_DIALING.
INCOMING_RINGING	3	There is a callsetup procedure in progress for an incoming call.
INCOMING_WAITING	4	There is a callsetup procedure in progress for an incoming call.
ONGOING_HELD	5	A call is in progress but another call is active.
ONGOING_ACTIVE	6	A call is active.
TERMINATED	7	The call has been termianted.
TRANSFERRED_TO_AG	8	The call has been transferred to the AG, after which the HF is no longer tracking its state.

DtmfCode strict

Type: uint8

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Dual-tone multi-frequency signaling codes.

Name	Value	Description
ONE	49	Represented by ASCII "1" in AT commands.
TWO	50	Represented by ASCII "2" in AT commands.
THREE	51	Represented by ASCII "3" in AT commands.
FOUR	52	Represented by ASCII "4" in AT commands.
FIVE	53	Represented by ASCII "5" in AT commands.
SIX	54	Represented by ASCII "6" in AT commands.
SEVEN	55	Represented by ASCII "7" in AT commands.
EIGHT	56	Represented by ASCII "8" in AT commands.
NINE	57	Represented by ASCII "9" in AT commands.
NUMBER_SIGN	35	Represented by ASCII "#" in AT commands.
ZERO	48	Represented by ASCII "0" in AT commands.
ASTERISK	42	Represented by ASCII "*" in AT commands.
A	65	Represented by ASCII "A" in AT commands.
B	66	Represented by ASCII "B" in AT commands.
C	67	Represented by ASCII "C" in AT commands.
D	68	Represented by ASCII "D" in AT commands.

SignalStrength strict

Type: int8

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Represents the signal strength of a connection between the Audio Gateway and a network.

Name	Value	Description
NONE	1
VERY_LOW	2
LOW	3
MEDIUM	4
HIGH	5
VERY_HIGH	6

TABLES

NetworkInformation

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Network information for the Audio Gateway. Typically this represents information regarding the state of connectivity to a telephony network.

Ordinal	Field	Type	Description
1	service_available	bool	Report the status of registration with the network. See HFP v1.8, Section 4.4
2	signal_strength	SignalStrength	Report the signal strength of the connection to the network. See the HFP v1.8, Section 4.5.
3	roaming	bool	Report the roaming status of the connection to the network. See HFP v1.8, Section 4.6

NextCall resource

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Information for the next call reported by a Peer Handler.

Ordinal	Field	Type	Description
1	call	client_end:Call	Channel for this call. This field is required.
2	remote	Number	The Number of the remote party on the call. This field is required.
3	state	CallState	State of the call when it is reported by the Peer Handler. This field is required.
4	direction	CallDirection	Direction of the call's initiation. See CallDirection documentation for more information. This field is required.

UNIONS

CallAction strict

Defined in fuchsia.bluetooth.hfp/hfp.fidl

A command from the HF with a value representing what number to dial.

Ordinal	Variant	Type	Description
1	dial_from_number	Number	A complete number to be dialed by the call handler service. See HFP v1.8 Section 4.18.
2	dial_from_location	Memory	A phone book memory location from which a number to be dialed should be looked up. See HFP v1.8 Section 4.19.
3	redial_last	RedialLast	The call handler service should dial the last used number. See HFP v1.8 Section 4.20.
4	transfer_active	TransferActive	Request to transfer an active call to the headset rather than initiating a new outgoing call. A call must already be in progress on the Audio Gateway in order for a transfer of audio to the Hands-Free device to take place. See HFP v1.8 Section 4.16.

Call_SendDtmfCode_Result strict

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Ordinal	Variant	Type	Description
1	response	Call_SendDtmfCode_Response
2	err	zx/Status

HandsFree_WatchPeerConnected_Result strict resource

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Ordinal	Variant	Type	Description
1	response	HandsFree_WatchPeerConnected_Response
2	err	zx/Status

PeerHandler_RequestOutgoingCall_Result strict

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Ordinal	Variant	Type	Description
1	response	PeerHandler_RequestOutgoingCall_Response
2	err	zx/Status

PeerHandler_SetNrecMode_Result strict

Defined in fuchsia.bluetooth.hfp/hfp.fidl

Ordinal	Variant	Type	Description
1	response	PeerHandler_SetNrecMode_Response
2	err	zx/Status

CONSTANTS

Name	Value	Type	Description
MAX_PICONET_SIZE	8	uint64

ALIASES

Name	Value	Description
Memory	string[256]	Represents a specific phone book memory location.
Number	string[256]	Represents a text string of V.250 dialing digits. See TS 127.007v06.08.00, Section 6.2 for more information.