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("about to write (fd=%d, len=%d)\n", h->fd, len);
87 n = adb_write(h->fd, data, len);
88 if(n != len) {
89 D("ERROR: fd = %d, n = %d, errno = %d (%s)\n",
90 h->fd, n, errno, strerror(errno));
91 return -1;
92 }
93 D("[ done fd=%d ]\n", h->fd);
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("about to read (fd=%d, len=%d)\n", h->fd, len);
102 n = adb_read(h->fd, data, len);
103 if(n != len) {
104 D("ERROR: fd = %d, n = %d, errno = %d (%s)\n",
105 h->fd, n, errno, strerror(errno));
106 return -1;
107 }
108 D("[ done fd=%d ]\n", h->fd);
109 return 0;
110 }
111
usb_init()112 void usb_init()
113 {
114 usb_handle *h;
115 adb_thread_t tid;
116 int fd;
117
118 h = calloc(1, sizeof(usb_handle));
119 h->fd = -1;
120 adb_cond_init(&h->notify, 0);
121 adb_mutex_init(&h->lock, 0);
122
123 // Open the file /dev/android_adb_enable to trigger
124 // the enabling of the adb USB function in the kernel.
125 // We never touch this file again - just leave it open
126 // indefinitely so the kernel will know when we are running
127 // and when we are not.
128 fd = unix_open("/dev/android_adb_enable", O_RDWR);
129 if (fd < 0) {
130 D("failed to open /dev/android_adb_enable\n");
131 } else {
132 close_on_exec(fd);
133 }
134
135 D("[ usb_init - starting thread ]\n");
136 if(adb_thread_create(&tid, usb_open_thread, h)){
137 fatal_errno("cannot create usb thread");
138 }
139 }
140
usb_kick(usb_handle * h)141 void usb_kick(usb_handle *h)
142 {
143 D("usb_kick\n");
144 adb_mutex_lock(&h->lock);
145 adb_close(h->fd);
146 h->fd = -1;
147
148 // notify usb_open_thread that we are disconnected
149 adb_cond_signal(&h->notify);
150 adb_mutex_unlock(&h->lock);
151 }
152
usb_close(usb_handle * h)153 int usb_close(usb_handle *h)
154 {
155 // nothing to do here
156 return 0;
157 }
158