1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS 24 * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define __BTSTACK_FILE__ "spp_flowcontrol.c" 39 40 // ***************************************************************************** 41 /* EXAMPLE_START(spp_flowcontrol): SPP Server - Flow Control 42 * 43 * @text This example adds explicit flow control for incoming RFCOMM data to the 44 * SPP heartbeat counter example. We will highlight the changes compared to the 45 * SPP counter example. 46 */ 47 // ***************************************************************************** 48 49 #include <stdint.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <string.h> 53 54 #include "btstack.h" 55 56 #define HEARTBEAT_PERIOD_MS 500 57 58 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 59 60 static uint8_t rfcomm_channel_nr = 1; 61 static uint16_t rfcomm_channel_id; 62 static uint8_t rfcomm_send_credit = 0; 63 static uint8_t spp_service_buffer[150]; 64 static btstack_packet_callback_registration_t hci_event_callback_registration; 65 66 /* @section SPP Service Setup 67 * 68 * @text Listing explicitFlowControl shows how to 69 * provide one initial credit during RFCOMM service initialization. Please note 70 * that providing a single credit effectively reduces the credit-based (sliding 71 * window) flow control to a stop-and-wait flow control that limits the data 72 * throughput substantially. 73 */ 74 75 /* LISTING_START(explicitFlowControl): Providing one initial credit during RFCOMM service initialization */ 76 static void spp_service_setup(void){ 77 78 // register for HCI events 79 hci_event_callback_registration.callback = &packet_handler; 80 hci_add_event_handler(&hci_event_callback_registration); 81 82 // init L2CAP 83 l2cap_init(); 84 85 // init RFCOMM 86 rfcomm_init(); 87 // reserved channel, mtu limited by l2cap, 1 credit 88 rfcomm_register_service_with_initial_credits(&packet_handler, rfcomm_channel_nr, 0xffff, 1); 89 90 // init SDP, create record for SPP and register with SDP 91 sdp_init(); 92 memset(spp_service_buffer, 0, sizeof(spp_service_buffer)); 93 spp_create_sdp_record(spp_service_buffer, 0x10001, 1, "SPP Counter"); 94 sdp_register_service(spp_service_buffer); 95 printf("SDP service buffer size: %u\n\r", (uint16_t) de_get_len(spp_service_buffer)); 96 } 97 /* LISTING_END */ 98 99 /* @section Periodic Timer Setup 100 * 101 * @text Explicit credit management is 102 * recommended when received RFCOMM data cannot be processed immediately. In this 103 * example, delayed processing of received data is simulated with the help of a 104 * periodic timer as follows. When the packet handler receives a data packet, it 105 * does not provide a new credit, it sets a flag instead, see Listing phManual. 106 * If the flag is set, a new 107 * credit will be granted by the heartbeat handler, introducing a delay of up to 1 108 * second. The heartbeat handler code is shown in Listing hbhManual. 109 */ 110 111 static btstack_timer_source_t heartbeat; 112 113 /* LISTING_START(hbhManual): Heartbeat handler with manual credit management */ 114 static void heartbeat_handler(struct btstack_timer_source *ts){ 115 if (rfcomm_send_credit){ 116 rfcomm_grant_credits(rfcomm_channel_id, 1); 117 rfcomm_send_credit = 0; 118 } 119 btstack_run_loop_set_timer(ts, HEARTBEAT_PERIOD_MS); 120 btstack_run_loop_add_timer(ts); 121 } 122 /* LISTING_END */ 123 124 static void one_shot_timer_setup(void){ 125 heartbeat.process = &heartbeat_handler; 126 btstack_run_loop_set_timer(&heartbeat, HEARTBEAT_PERIOD_MS); 127 btstack_run_loop_add_timer(&heartbeat); 128 } 129 130 /* LISTING_START(phManual): Packet handler with manual credit management */ 131 // Bluetooth logic 132 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 133 /* LISTING_PAUSE */ 134 bd_addr_t event_addr; 135 uint8_t rfcomm_channel_nr; 136 uint16_t mtu; 137 int i; 138 139 switch (packet_type) { 140 case HCI_EVENT_PACKET: 141 switch (hci_event_packet_get_type(packet)) { 142 143 case HCI_EVENT_COMMAND_COMPLETE: 144 if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)){ 145 reverse_bd_addr(&packet[6], event_addr); 146 printf("BD-ADDR: %s\n\r", bd_addr_to_str(event_addr)); 147 break; 148 } 149 break; 150 151 case HCI_EVENT_PIN_CODE_REQUEST: 152 // inform about pin code request 153 printf("Pin code request - using '0000'\n"); 154 hci_event_pin_code_request_get_bd_addr(packet, event_addr); 155 gap_pin_code_response(event_addr, "0000"); 156 break; 157 158 case RFCOMM_EVENT_INCOMING_CONNECTION: 159 // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16) 160 rfcomm_event_incoming_connection_get_bd_addr(packet, event_addr); 161 rfcomm_channel_nr = rfcomm_event_incoming_connection_get_server_channel(packet); 162 rfcomm_channel_id = rfcomm_event_incoming_connection_get_rfcomm_cid(packet); 163 printf("RFCOMM channel %u requested for %s\n", rfcomm_channel_nr, bd_addr_to_str(event_addr)); 164 rfcomm_accept_connection(rfcomm_channel_id); 165 break; 166 167 case RFCOMM_EVENT_CHANNEL_OPENED: 168 // data: event(8), len(8), status (8), address (48), server channel(8), rfcomm_cid(16), max frame size(16) 169 if (rfcomm_event_channel_opened_get_status(packet)) { 170 printf("RFCOMM channel open failed, status %u\n", rfcomm_event_channel_opened_get_status(packet)); 171 } else { 172 rfcomm_channel_id = rfcomm_event_channel_opened_get_rfcomm_cid(packet); 173 mtu = rfcomm_event_channel_opened_get_max_frame_size(packet); 174 printf("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u\n", rfcomm_channel_id, mtu); 175 } 176 break; 177 178 case RFCOMM_EVENT_CHANNEL_CLOSED: 179 rfcomm_channel_id = 0; 180 break; 181 182 default: 183 break; 184 } 185 break; 186 /* LISTING_RESUME */ 187 case RFCOMM_DATA_PACKET: 188 for (i=0;i<size;i++){ 189 putchar(packet[i]); 190 }; 191 putchar('\n'); 192 rfcomm_send_credit = 1; 193 break; 194 /* LISTING_PAUSE */ 195 default: 196 break; 197 } 198 /* LISTING_RESUME */ 199 } 200 /* LISTING_END */ 201 202 203 204 int btstack_main(int argc, const char * argv[]); 205 int btstack_main(int argc, const char * argv[]){ 206 207 spp_service_setup(); 208 one_shot_timer_setup(); 209 210 puts("SPP FlowControl Demo: simulates processing on received data...\n\r"); 211 gap_set_local_name("SPP Flowcontrol 00:00:00:00:00:00"); 212 gap_discoverable_control(1); 213 214 // turn on! 215 hci_power_control(HCI_POWER_ON); 216 217 return 0; 218 } 219 /* EXAMPLE_END */ 220 221 222