1 /*
2 * Copyright (C) 2007 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 #include <stdio.h>
18 #include <stdlib.h>
19 #include <unistd.h>
20 #include <string.h>
21
22 #include <sys/ioctl.h>
23 #include <sys/types.h>
24 #include <dirent.h>
25 #include <errno.h>
26
27 #include "sysdeps.h"
28
29 #define TRACE_TAG TRACE_USB
30 #include "adb.h"
31
32
33 struct usb_handle
34 {
35 int fd;
36 adb_cond_t notify;
37 adb_mutex_t lock;
38 };
39
usb_cleanup()40 void usb_cleanup()
41 {
42 // nothing to do here
43 }
44
usb_open_thread(void * x)45 static void *usb_open_thread(void *x)
46 {
47 struct usb_handle *usb = (struct usb_handle *)x;
48 int fd;
49
50 while (1) {
51 // wait until the USB device needs opening
52 adb_mutex_lock(&usb->lock);
53 while (usb->fd != -1)
54 adb_cond_wait(&usb->notify, &usb->lock);
55 adb_mutex_unlock(&usb->lock);
56
57 D("[ usb_thread - opening device ]\n");
58 do {
59 /* XXX use inotify? */
60 fd = unix_open("/dev/android_adb", O_RDWR);
61 if (fd < 0) {
62 // to support older kernels
63 fd = unix_open("/dev/android", O_RDWR);
64 }
65 if (fd < 0) {
66 adb_sleep_ms(1000);
67 }
68 } while (fd < 0);
69 D("[ opening device succeeded ]\n");
70
71 close_on_exec(fd);
72 usb->fd = fd;
73
74 D("[ usb_thread - registering device ]\n");
75 register_usb_transport(usb, 0, 1);
76 }
77
78 // never gets here
79 return 0;
80 }
81
usb_write(usb_handle * h,const void * data,int len)82 int usb_write(usb_handle *h, const void *data, int len)
83 {
84 int n;
85
86 D("[ write %d ]\n", len);
87 n = adb_write(h->fd, data, len);
88 if(n != len) {
89 D("ERROR: n = %d, errno = %d (%s)\n",
90 n, errno, strerror(errno));
91 return -1;
92 }
93 D("[ done ]\n");
94 return 0;
95 }
96
usb_read(usb_handle * h,void * data,int len)97 int usb_read(usb_handle *h, void *data, int len)
98 {
99 int n;
100
101 D("[ read %d ]\n", len);
102 n = adb_read(h->fd, data, len);
103 if(n != len) {
104 D("ERROR: n = %d, errno = %d (%s)\n",
105 n, errno, strerror(errno));
106 return -1;
107 }
108 return 0;
109 }
110
usb_init()111 void usb_init()
112 {
113 usb_handle *h;
114 adb_thread_t tid;
115 int fd;
116
117 h = calloc(1, sizeof(usb_handle));
118 h->fd = -1;
119 adb_cond_init(&h->notify, 0);
120 adb_mutex_init(&h->lock, 0);
121
122 // Open the file /dev/android_adb_enable to trigger
123 // the enabling of the adb USB function in the kernel.
124 // We never touch this file again - just leave it open
125 // indefinitely so the kernel will know when we are running
126 // and when we are not.
127 fd = unix_open("/dev/android_adb_enable", O_RDWR);
128 if (fd < 0) {
129 D("failed to open /dev/android_adb_enable\n");
130 } else {
131 close_on_exec(fd);
132 }
133
134 D("[ usb_init - starting thread ]\n");
135 if(adb_thread_create(&tid, usb_open_thread, h)){
136 fatal_errno("cannot create usb thread");
137 }
138 }
139
usb_kick(usb_handle * h)140 void usb_kick(usb_handle *h)
141 {
142 D("usb_kick\n");
143 adb_mutex_lock(&h->lock);
144 adb_close(h->fd);
145 h->fd = -1;
146
147 // notify usb_open_thread that we are disconnected
148 adb_cond_signal(&h->notify);
149 adb_mutex_unlock(&h->lock);
150 }
151
usb_close(usb_handle * h)152 int usb_close(usb_handle *h)
153 {
154 // nothing to do here
155 return 0;
156 }
157