bluetooth.c revision df782f29a530d805c13f32bb43883306c05a4504 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "bluedroid"
18
19#include <errno.h>
20#include <fcntl.h>
21#include <sys/ioctl.h>
22#include <sys/socket.h>
23#include <sys/types.h>
24#include <sys/stat.h>
25
26#include <cutils/log.h>
27#include <cutils/properties.h>
28
29#include <bluetooth/bluetooth.h>
30#include <bluetooth/hci.h>
31#include <bluetooth/hci_lib.h>
32
33#include <bluedroid/bluetooth.h>
34
35#ifndef HCI_DEV_ID
36#define HCI_DEV_ID 0
37#endif
38
39#define HCID_START_DELAY_SEC   3
40#define HCID_STOP_DELAY_USEC 500000
41
42#define MIN(x,y) (((x)<(y))?(x):(y))
43
44
45static int rfkill_id = -1;
46static char *rfkill_state_path = NULL;
47
48
49static int init_rfkill() {
50    char path[64];
51    char buf[16];
52    int fd;
53    int sz;
54    int id;
55    for (id = 0; ; id++) {
56        snprintf(path, sizeof(path), "/sys/class/rfkill/rfkill%d/type", id);
57        fd = open(path, O_RDONLY);
58        if (fd < 0) {
59            LOGW("open(%s) failed: %s (%d)\n", path, strerror(errno), errno);
60            return -1;
61        }
62        sz = read(fd, &buf, sizeof(buf));
63        close(fd);
64        if (sz >= 9 && memcmp(buf, "bluetooth", 9) == 0) {
65            rfkill_id = id;
66            break;
67        }
68    }
69
70    asprintf(&rfkill_state_path, "/sys/class/rfkill/rfkill%d/state", rfkill_id);
71    return 0;
72}
73
74static int check_bluetooth_power() {
75    int sz;
76    int fd = -1;
77    int ret = -1;
78    char buffer;
79
80    if (rfkill_id == -1) {
81        if (init_rfkill()) goto out;
82    }
83
84    fd = open(rfkill_state_path, O_RDONLY);
85    if (fd < 0) {
86        LOGE("open(%s) failed: %s (%d)", rfkill_state_path, strerror(errno),
87             errno);
88        goto out;
89    }
90    sz = read(fd, &buffer, 1);
91    if (sz != 1) {
92        LOGE("read(%s) failed: %s (%d)", rfkill_state_path, strerror(errno),
93             errno);
94        goto out;
95    }
96
97    switch (buffer) {
98    case '1':
99        ret = 1;
100        break;
101    case '0':
102        ret = 0;
103        break;
104    }
105
106out:
107    if (fd >= 0) close(fd);
108    return ret;
109}
110
111static int set_bluetooth_power(int on) {
112    int sz;
113    int fd = -1;
114    int ret = -1;
115    const char buffer = (on ? '1' : '0');
116
117    if (rfkill_id == -1) {
118        if (init_rfkill()) goto out;
119    }
120
121    fd = open(rfkill_state_path, O_WRONLY);
122    if (fd < 0) {
123        LOGE("open(%s) for write failed: %s (%d)", rfkill_state_path,
124             strerror(errno), errno);
125        goto out;
126    }
127    sz = write(fd, &buffer, 1);
128    if (sz < 0) {
129        LOGE("write(%s) failed: %s (%d)", rfkill_state_path, strerror(errno),
130             errno);
131        goto out;
132    }
133    ret = 0;
134
135out:
136    if (fd >= 0) close(fd);
137    return ret;
138}
139
140static inline int create_hci_sock() {
141    int sk = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
142    if (sk < 0) {
143        LOGE("Failed to create bluetooth hci socket: %s (%d)",
144             strerror(errno), errno);
145    }
146    return sk;
147}
148
149int bt_enable() {
150    LOGV(__FUNCTION__);
151
152    int ret = -1;
153    int hci_sock = -1;
154    int attempt;
155
156    if (set_bluetooth_power(1) < 0) goto out;
157
158    LOGI("Starting hciattach daemon");
159    if (property_set("ctl.start", "hciattach") < 0) {
160        LOGE("Failed to start hciattach");
161        goto out;
162    }
163
164    // Try for 10 seconds, this can only succeed once hciattach has sent the
165    // firmware and then turned on hci device via HCIUARTSETPROTO ioctl
166    for (attempt = 1000; attempt > 0;  attempt--) {
167        hci_sock = create_hci_sock();
168        if (hci_sock < 0) goto out;
169
170        if (!ioctl(hci_sock, HCIDEVUP, HCI_DEV_ID)) {
171            break;
172        }
173        close(hci_sock);
174        usleep(10000);  // 10 ms retry delay
175    }
176    if (attempt == 0) {
177        LOGE("%s: Timeout waiting for HCI device to come up", __FUNCTION__);
178        goto out;
179    }
180
181    LOGI("Starting hcid deamon");
182    if (property_set("ctl.start", "hcid") < 0) {
183        LOGE("Failed to start hcid");
184        goto out;
185    }
186    sleep(HCID_START_DELAY_SEC);
187
188    ret = 0;
189
190out:
191    if (hci_sock >= 0) close(hci_sock);
192    return ret;
193}
194
195int bt_disable() {
196    LOGV(__FUNCTION__);
197
198    int ret = -1;
199    int hci_sock = -1;
200
201    LOGI("Stopping hcid deamon");
202    if (property_set("ctl.stop", "hcid") < 0) {
203        LOGE("Error stopping hcid");
204        goto out;
205    }
206    usleep(HCID_STOP_DELAY_USEC);
207
208    hci_sock = create_hci_sock();
209    if (hci_sock < 0) goto out;
210    ioctl(hci_sock, HCIDEVDOWN, HCI_DEV_ID);
211
212    LOGI("Stopping hciattach deamon");
213    if (property_set("ctl.stop", "hciattach") < 0) {
214        LOGE("Error stopping hciattach");
215        goto out;
216    }
217
218    if (set_bluetooth_power(0) < 0) {
219        goto out;
220    }
221    ret = 0;
222
223out:
224    if (hci_sock >= 0) close(hci_sock);
225    return ret;
226}
227
228int bt_is_enabled() {
229    LOGV(__FUNCTION__);
230
231    int hci_sock = -1;
232    int ret = -1;
233    struct hci_dev_info dev_info;
234
235
236    // Check power first
237    ret = check_bluetooth_power();
238    if (ret == -1 || ret == 0) goto out;
239
240    ret = -1;
241
242    // Power is on, now check if the HCI interface is up
243    hci_sock = create_hci_sock();
244    if (hci_sock < 0) goto out;
245
246    dev_info.dev_id = HCI_DEV_ID;
247    if (ioctl(hci_sock, HCIGETDEVINFO, (void *)&dev_info) < 0) {
248        ret = 0;
249        goto out;
250    }
251
252    ret = hci_test_bit(HCI_UP, &dev_info.flags);
253
254out:
255    if (hci_sock >= 0) close(hci_sock);
256    return ret;
257}
258