/*
* Copyright (C) 2014 BlueKitchen GmbH
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holders nor the names of
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
* 4. Any redistribution, use, or modification is done solely for
* personal benefit and not for any commercial purpose or for
* monetary gain.
*
* THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
* RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
* THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Please inquire about commercial licensing options at
* contact@bluekitchen-gmbh.com
*
*/
// *****************************************************************************
//
// Minimal setup for HSP Audio Gateway (!! UNDER DEVELOPMENT !!)
//
// *****************************************************************************
#include "btstack-config.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <btstack/hci_cmds.h>
#include <btstack/run_loop.h>
#include "hci.h"
#include "btstack_memory.h"
#include "hci_dump.h"
#include "l2cap.h"
#include "sdp_query_rfcomm.h"
#include "sdp.h"
#include "debug.h"
#include "hsp_ag.h"
#define RFCOMM_SERVER_CHANNEL 1
#define HSP_HS_BUTTON_PRESS "AT+CKPD=200\r\n"
#define HSP_HS_AT_CKPD "AT+CKPD\r\n"
#define HSP_AG_OK "\r\nOK\r\n"
#define HSP_AG_ERROR "\r\nERROR\r\n"
#define HSP_AG_RING "\r\nRING\r\n"
#define HSP_MICROPHONE_GAIN "+VGM"
#define HSP_SPEAKER_GAIN "+VGS"
#define HSP_HS_MICROPHONE_GAIN "AT+VGM="
#define HSP_HS_SPEAKER_GAIN "AT+VGS="
static const char default_hsp_ag_service_name[] = "Audio Gateway";
static bd_addr_t remote;
static uint8_t channel_nr = 0;
static uint16_t mtu;
static uint16_t rfcomm_cid = 0;
static uint16_t sco_handle = 0;
static uint16_t rfcomm_handle = 0;
static timer_source_t hs_timeout;
// static uint8_t connection_state = 0;
static int ag_microphone_gain = -1;
static int ag_speaker_gain = -1;
static uint8_t ag_ring = 0;
static uint8_t ag_send_ok = 0;
static uint8_t ag_send_error = 0;
static uint8_t ag_num_button_press_received = 0;
static uint8_t ag_support_custom_commands = 0;
typedef enum {
HSP_IDLE,
HSP_SDP_QUERY_RFCOMM_CHANNEL,
HSP_W4_SDP_QUERY_COMPLETE,
HSP_W4_RFCOMM_CONNECTED,
HSP_W4_RING_ANSWER,
HSP_W4_USER_ACTION,
HSP_W2_CONNECT_SCO,
HSP_W4_SCO_CONNECTED,
HSP_ACTIVE,
HSP_W2_DISCONNECT_SCO,
HSP_W4_SCO_DISCONNECTED,
HSP_W2_DISCONNECT_RFCOMM,
HSP_W4_RFCOMM_DISCONNECTED,
HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN
} hsp_state_t;
static hsp_state_t hsp_state = HSP_IDLE;
static hsp_ag_callback_t hsp_ag_callback;
static void hsp_run();
static void packet_handler (void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
static void handle_query_rfcomm_event(sdp_query_event_t * event, void * context);
static void dummy_notify(uint8_t * event, uint16_t size){}
void hsp_ag_register_packet_handler(hsp_ag_callback_t callback){
if (callback == NULL){
callback = &dummy_notify;
}
hsp_ag_callback = callback;
}
static void emit_event(uint8_t event_subtype, uint8_t value){
if (!hsp_ag_callback) return;
uint8_t event[4];
event[0] = HCI_EVENT_HSP_META;
event[1] = sizeof(event) - 2;
event[2] = event_subtype;
event[3] = value; // status 0 == OK
(*hsp_ag_callback)(event, sizeof(event));
}
void hsp_ag_create_service(uint8_t * service, int rfcomm_channel_nr, const char * name){
uint8_t* attribute;
de_create_sequence(service);
// 0x0000 "Service Record Handle"
de_add_number(service, DE_UINT, DE_SIZE_16, SDP_ServiceRecordHandle);
de_add_number(service, DE_UINT, DE_SIZE_32, 0x10001);
// 0x0001 "Service Class ID List"
de_add_number(service, DE_UINT, DE_SIZE_16, SDP_ServiceClassIDList);
attribute = de_push_sequence(service);
{
// "UUID for PAN Service"
de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_Headset_AG);
de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_GenericAudio);
}
de_pop_sequence(service, attribute);
// 0x0004 "Protocol Descriptor List"
de_add_number(service, DE_UINT, DE_SIZE_16, SDP_ProtocolDescriptorList);
attribute = de_push_sequence(service);
{
uint8_t* l2cpProtocol = de_push_sequence(attribute);
{
de_add_number(l2cpProtocol, DE_UUID, DE_SIZE_16, SDP_L2CAPProtocol);
}
de_pop_sequence(attribute, l2cpProtocol);
uint8_t* rfcomm = de_push_sequence(attribute);
{
de_add_number(rfcomm, DE_UUID, DE_SIZE_16, SDP_RFCOMMProtocol); // rfcomm_service
de_add_number(rfcomm, DE_UINT, DE_SIZE_8, rfcomm_channel_nr); // rfcomm channel
}
de_pop_sequence(attribute, rfcomm);
}
de_pop_sequence(service, attribute);
// 0x0005 "Public Browse Group"
de_add_number(service, DE_UINT, DE_SIZE_16, SDP_BrowseGroupList); // public browse group
attribute = de_push_sequence(service);
{
de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_PublicBrowseGroup);
}
de_pop_sequence(service, attribute);
// 0x0009 "Bluetooth Profile Descriptor List"
de_add_number(service, DE_UINT, DE_SIZE_16, SDP_BluetoothProfileDescriptorList);
attribute = de_push_sequence(service);
{
uint8_t *sppProfile = de_push_sequence(attribute);
{
de_add_number(sppProfile, DE_UUID, DE_SIZE_16, SDP_HSP);
de_add_number(sppProfile, DE_UINT, DE_SIZE_16, 0x0102); // Verision 1.2
}
de_pop_sequence(attribute, sppProfile);
}
de_pop_sequence(service, attribute);
// 0x0100 "Service Name"
de_add_number(service, DE_UINT, DE_SIZE_16, 0x0100);
if (name){
de_add_data(service, DE_STRING, strlen(name), (uint8_t *) name);
} else {
de_add_data(service, DE_STRING, strlen(default_hsp_ag_service_name), (uint8_t *) default_hsp_ag_service_name);
}
}
static int send_str_over_rfcomm(uint16_t cid, char * command){
if (!rfcomm_can_send_packet_now(rfcomm_cid)) return 1;
int err = rfcomm_send_internal(cid, (uint8_t*) command, strlen(command));
if (err){
printf("rfcomm_send_internal -> error 0X%02x", err);
return err;
}
printf("Send string: \"%s\"\n", command);
return err;
}
void hsp_ag_support_custom_commands(int enable){
ag_support_custom_commands = enable;
}
int hsp_ag_send_result(char * result){
if (!ag_support_custom_commands) return 1;
return send_str_over_rfcomm(rfcomm_cid, result);
}
static void hsp_ag_reset_state(){
hsp_state = HSP_IDLE;
rfcomm_cid = 0;
rfcomm_handle = 0;
sco_handle = 0;
ag_send_ok = 0;
ag_send_error = 0;
ag_ring = 0;
ag_num_button_press_received = 0;
ag_support_custom_commands = 0;
ag_microphone_gain = -1;
ag_speaker_gain = -1;
}
void hsp_ag_init(uint8_t rfcomm_channel_nr){
// init L2CAP
l2cap_init();
l2cap_register_packet_handler(packet_handler);
rfcomm_init();
rfcomm_register_packet_handler(packet_handler);
rfcomm_register_service_internal(NULL, rfcomm_channel_nr, 0xffff); // reserved channel, mtu limited by l2cap
sdp_query_rfcomm_register_callback(handle_query_rfcomm_event, NULL);
hsp_ag_reset_state();
}
void hsp_ag_connect(bd_addr_t bd_addr){
if (hsp_state != HSP_IDLE) return;
hsp_state = HSP_SDP_QUERY_RFCOMM_CHANNEL;
memcpy(remote, bd_addr, 6);
hsp_run();
}
void hsp_ag_disconnect(){
switch (hsp_state){
case HSP_ACTIVE:
hsp_state = HSP_W2_DISCONNECT_SCO;
break;
case HSP_W2_CONNECT_SCO:
hsp_state = HSP_W2_DISCONNECT_RFCOMM;
break;
case HSP_W4_RFCOMM_CONNECTED:
case HSP_W4_SCO_CONNECTED:
hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
break;
default:
return;
}
hsp_run();
}
void hsp_ag_set_microphone_gain(uint8_t gain){
if (gain < 0 || gain >15) {
printf("Gain must be in interval [0..15], it is given %d\n", gain);
return;
}
ag_microphone_gain = gain;
hsp_run();
}
// AG +VGS=5 [0..15] ; HS AT+VGM=6 | AG OK
void hsp_ag_set_speaker_gain(uint8_t gain){
if (gain < 0 || gain >15) {
printf("Gain must be in interval [0..15], it is given %d\n", gain);
return;
}
ag_speaker_gain = gain;
hsp_run();
}
static void hsp_timeout_handler(timer_source_t * timer){
ag_ring = 1;
}
static void hsp_timeout_start(){
run_loop_remove_timer(&hs_timeout);
run_loop_set_timer_handler(&hs_timeout, hsp_timeout_handler);
run_loop_set_timer(&hs_timeout, 2000); // 2 seconds timeout
run_loop_add_timer(&hs_timeout);
}
static void hsp_timeout_stop(){
run_loop_remove_timer(&hs_timeout);
}
void hsp_ag_start_ringing(){
if (hsp_state != HSP_W2_CONNECT_SCO) return;
ag_ring = 1;
hsp_state = HSP_W4_RING_ANSWER;
hsp_timeout_start();
}
void hsp_ag_stop_ringing(){
ag_ring = 0;
ag_num_button_press_received = 0;
hsp_state = HSP_W2_CONNECT_SCO;
hsp_timeout_stop();
}
static void hsp_run(){
int err;
if (ag_send_ok){
err = send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
if (!err){
ag_send_ok = 0;
}
return;
}
if (ag_send_error){
err = send_str_over_rfcomm(rfcomm_cid, HSP_AG_ERROR);
if (!err) ag_send_error = 0;
return;
}
switch (hsp_state){
case HSP_SDP_QUERY_RFCOMM_CHANNEL:
hsp_state = HSP_W4_SDP_QUERY_COMPLETE;
printf("Start SDP query %s, 0x%02x\n", bd_addr_to_str(remote), SDP_HSP);
sdp_query_rfcomm_channel_and_name_for_uuid(remote, SDP_HSP);
break;
case HSP_W4_RING_ANSWER:
if (ag_ring){
err = send_str_over_rfcomm(rfcomm_cid, HSP_AG_RING);
if (!err) ag_ring = 0;
break;
}
if (!ag_num_button_press_received) break;
err = send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
if (!err) {
hsp_state = HSP_W2_CONNECT_SCO;
ag_send_ok = 0;
ag_num_button_press_received = 0;
}
break;
case HSP_W2_CONNECT_SCO:
if (!hci_can_send_command_packet_now()) break;
hsp_state = HSP_W4_SCO_CONNECTED;
hci_send_cmd(&hci_setup_synchronous_connection_command, rfcomm_handle, 8000, 8000, 0xFFFF, 0x0060, 0xFF, 0x003F);
break;
case HSP_W2_DISCONNECT_SCO:
ag_num_button_press_received = 0;
hsp_state = HSP_W4_SCO_DISCONNECTED;
gap_disconnect(sco_handle);
break;
case HSP_W2_DISCONNECT_RFCOMM:
hsp_state = HSP_W4_RFCOMM_DISCONNECTED;
rfcomm_disconnect_internal(rfcomm_cid);
break;
case HSP_ACTIVE:
if (ag_microphone_gain >= 0){
char buffer[10];
sprintf(buffer, "%s=%d\r\n", HSP_MICROPHONE_GAIN, ag_microphone_gain);
err = send_str_over_rfcomm(rfcomm_cid, buffer);
if (!err) ag_microphone_gain = -1;
break;
}
if (ag_speaker_gain >= 0){
char buffer[10];
sprintf(buffer, "%s=%d\r\n", HSP_SPEAKER_GAIN, ag_speaker_gain);
err = send_str_over_rfcomm(rfcomm_cid, buffer);
if (!err) ag_speaker_gain = -1;
break;
}
break;
default:
break;
}
}
static void packet_handler (void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
// printf("packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
if (packet_type == RFCOMM_DATA_PACKET){
while (size > 0 && (packet[0] == '\n' || packet[0] == '\r')){
size--;
packet++;
}
if (strncmp((char *)packet, HSP_HS_BUTTON_PRESS, strlen(HSP_HS_BUTTON_PRESS)) == 0){
printf("Received button press %s\n", HSP_HS_BUTTON_PRESS);
ag_num_button_press_received++;
ag_send_ok = 1;
if (hsp_state == HSP_ACTIVE && ag_num_button_press_received >=2){
ag_num_button_press_received = 0;
hsp_state = HSP_W2_DISCONNECT_SCO;
}
} else if (strncmp((char *)packet, HSP_HS_MICROPHONE_GAIN, strlen(HSP_HS_MICROPHONE_GAIN)) == 0){
uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_HS_MICROPHONE_GAIN)]);
ag_send_ok = 1;
emit_event(HSP_SUBEVENT_MICROPHONE_GAIN_CHANGED, gain);
} else if (strncmp((char *)packet, HSP_HS_SPEAKER_GAIN, strlen(HSP_HS_SPEAKER_GAIN)) == 0){
uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_HS_SPEAKER_GAIN)]);
ag_send_ok = 1;
emit_event(HSP_SUBEVENT_SPEAKER_GAIN_CHANGED, gain);
} else if (strncmp((char *)packet, "AT+", 3) == 0){
ag_send_error = 1;
if (!hsp_ag_callback) return;
// re-use incoming buffer to avoid reserving large buffers - ugly but efficient
uint8_t * event = packet - 3;
event[0] = HCI_EVENT_HSP_META;
event[1] = size + 1;
event[2] = HSP_SUBEVENT_HS_COMMAND;
(*hsp_ag_callback)(event, size+3);
}
hsp_run();
return;
}
if (packet_type != HCI_EVENT_PACKET) return;
uint8_t event = packet[0];
bd_addr_t event_addr;
uint16_t handle;
switch (event) {
case BTSTACK_EVENT_STATE:
// BTstack activated, get started
if (packet[2] == HCI_STATE_WORKING){
printf("BTstack activated, get started .\n");
}
break;
case HCI_EVENT_PIN_CODE_REQUEST:
// inform about pin code request
printf("Pin code request - using '0000'\n\r");
bt_flip_addr(event_addr, &packet[2]);
hci_send_cmd(&hci_pin_code_request_reply, &event_addr, 4, "0000");
break;
case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
int index = 2;
uint8_t status = packet[index++];
sco_handle = READ_BT_16(packet, index);
index+=2;
bd_addr_t address;
memcpy(address, &packet[index], 6);
index+=6;
uint8_t link_type = packet[index++];
uint8_t transmission_interval = packet[index++]; // measured in slots
uint8_t retransmission_interval = packet[index++];// measured in slots
uint16_t rx_packet_length = READ_BT_16(packet, index); // measured in bytes
index+=2;
uint16_t tx_packet_length = READ_BT_16(packet, index); // measured in bytes
index+=2;
uint8_t air_mode = packet[index];
if (status != 0){
log_error("(e)SCO Connection is not established, status %u", status);
exit(0);
break;
}
switch (link_type){
case 0x00:
printf("SCO Connection established. \n");
if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
break;
case 0x02:
printf("eSCO Connection established. \n");
break;
default:
log_error("(e)SCO reserved link_type 0x%2x", link_type);
break;
}
log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
" rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)", sco_handle,
bd_addr_to_str(address), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length, air_mode);
if (hsp_state == HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN){
hsp_state = HSP_W2_DISCONNECT_SCO;
break;
}
hsp_state = HSP_ACTIVE;
emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, 0);
break;
}
case RFCOMM_EVENT_INCOMING_CONNECTION:
// data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
if (hsp_state != HSP_IDLE) return;
bt_flip_addr(event_addr, &packet[2]);
rfcomm_cid = READ_BT_16(packet, 9);
printf("RFCOMM channel %u requested for %s\n", packet[8], bd_addr_to_str(event_addr));
rfcomm_accept_connection_internal(rfcomm_cid);
hsp_state = HSP_W4_RFCOMM_CONNECTED;
break;
case RFCOMM_EVENT_OPEN_CHANNEL_COMPLETE:
printf("RFCOMM_EVENT_OPEN_CHANNEL_COMPLETE packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
// data: event(8), len(8), status (8), address (48), handle(16), server channel(8), rfcomm_cid(16), max frame size(16)
if (packet[2]) {
printf("RFCOMM channel open failed, status %u\n", packet[2]);
hsp_ag_reset_state();
emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, packet[2]);
} else {
// data: event(8) , len(8), status (8), address (48), handle (16), server channel(8), rfcomm_cid(16), max frame size(16)
rfcomm_handle = READ_BT_16(packet, 9);
rfcomm_cid = READ_BT_16(packet, 12);
mtu = READ_BT_16(packet, 14);
printf("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u, state %d\n", rfcomm_cid, mtu, hsp_state);
switch (hsp_state){
case HSP_W4_RFCOMM_CONNECTED:
ag_num_button_press_received = 0;
hsp_state = HSP_W2_CONNECT_SCO;
break;
case HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN:
hsp_state = HSP_W2_DISCONNECT_RFCOMM;
break;
default:
printf("no valid state\n");
break;
}
}
break;
case DAEMON_EVENT_HCI_PACKET_SENT:
case RFCOMM_EVENT_CREDITS:
break;
case HCI_EVENT_DISCONNECTION_COMPLETE:
if (hsp_state != HSP_W4_SCO_DISCONNECTED){
log_info("received gap disconnect in wrong hsp state");
}
handle = READ_BT_16(packet,3);
if (handle == sco_handle){
printf("SCO disconnected, w2 disconnect RFCOMM\n");
sco_handle = 0;
hsp_state = HSP_W2_DISCONNECT_RFCOMM;
break;
}
break;
case RFCOMM_EVENT_CHANNEL_CLOSED:
if (hsp_state != HSP_W4_RFCOMM_DISCONNECTED){
log_info("received RFCOMM disconnect in wrong hsp state");
}
printf("RFCOMM channel closed\n");
hsp_ag_reset_state();
emit_event(HSP_SUBEVENT_AUDIO_DISCONNECTION_COMPLETE,0);
break;
default:
break;
}
hsp_run();
}
static void handle_query_rfcomm_event(sdp_query_event_t * event, void * context){
sdp_query_rfcomm_service_event_t * ve;
sdp_query_complete_event_t * ce;
switch (event->type){
case SDP_QUERY_RFCOMM_SERVICE:
ve = (sdp_query_rfcomm_service_event_t*) event;
channel_nr = ve->channel_nr;
printf("** Service name: '%s', RFCOMM port %u\n", ve->service_name, channel_nr);
break;
case SDP_QUERY_COMPLETE:
ce = (sdp_query_complete_event_t*) event;
if (channel_nr > 0){
hsp_state = HSP_W4_RFCOMM_CONNECTED;
printf("RFCOMM create channel. state %d\n", HSP_W4_RFCOMM_CONNECTED);
rfcomm_create_channel_internal(NULL, remote, channel_nr);
break;
}
hsp_ag_reset_state();
printf("Service not found, status %u.\n", ce->status);
if (ce->status){
emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, ce->status);
} else {
emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, SDP_SERVICE_NOT_FOUND);
}
break;
default:
break;
}
}