1 /*
2  * Copyright (C) 2012 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 <stdint.h>
20 #include <signal.h>
21 #include <pthread.h>
22 #include <errno.h>
23 #include <string.h>
24 
25 #include <usbhost/usbhost.h>
26 #include "f_accessory.h"
27 
28 #include "accessory.h"
29 
30 static struct usb_device *current_device = NULL;
31 static uint8_t read_ep;
32 static uint8_t write_ep;
33 
34 static pthread_mutex_t device_mutex = PTHREAD_MUTEX_INITIALIZER;
35 static pthread_cond_t device_cond = PTHREAD_COND_INITIALIZER;
36 
milli_sleep(int millis)37 static void milli_sleep(int millis) {
38     struct timespec tm;
39 
40     tm.tv_sec = 0;
41     tm.tv_nsec = millis * 1000000;
42     nanosleep(&tm, NULL);
43 }
44 
read_thread(void * arg)45 static void* read_thread(void* arg) {
46     int ret = 0;
47 
48     while (current_device && ret >= 0) {
49         char    buffer[16384];
50 
51         ret = usb_device_bulk_transfer(current_device, read_ep, buffer, sizeof(buffer), 1000);
52         if (ret < 0 && errno == ETIMEDOUT)
53             ret = 0;
54         if (ret > 0) {
55             fwrite(buffer, 1, ret, stdout);
56             fprintf(stderr, "\n");
57             fflush(stdout);
58         }
59     }
60 
61     return NULL;
62 }
63 
write_thread(void * arg)64 static void* write_thread(void* arg) {
65     int ret = 0;
66 
67     while (ret >= 0) {
68         char    buffer[16384];
69         char *line = fgets(buffer, sizeof(buffer), stdin);
70         if (!line || !current_device)
71             break;
72         ret = usb_device_bulk_transfer(current_device, write_ep, line, strlen(line), 1000);
73     }
74 
75     return NULL;
76 }
77 
send_string(struct usb_device * device,int index,const char * string)78 static void send_string(struct usb_device *device, int index, const char* string) {
79     usb_device_control_transfer(device, USB_DIR_OUT | USB_TYPE_VENDOR,
80             ACCESSORY_SEND_STRING, 0, index, (void *)string, strlen(string) + 1, 0);
81 
82     // some devices can't handle back-to-back requests, so delay a bit
83     milli_sleep(10);
84 }
85 
usb_device_added(const char * devname,void * client_data)86 static int usb_device_added(const char *devname, void* client_data) {
87     uint16_t vendorId, productId;
88     int ret;
89     int enable_accessory = (int)client_data;
90 
91     struct usb_device *device = usb_device_open(devname);
92     if (!device) {
93         fprintf(stderr, "usb_device_open failed\n");
94         return 0;
95     }
96 
97     vendorId = usb_device_get_vendor_id(device);
98     productId = usb_device_get_product_id(device);
99 
100     if (!current_device && vendorId == 0x18D1 && productId >= 0x2D00 && productId <= 0x2D05) {
101 
102         pthread_mutex_lock(&device_mutex);
103         fprintf(stderr, "Found android device in accessory mode\n");
104         current_device = device;
105         pthread_cond_broadcast(&device_cond);
106         pthread_mutex_unlock(&device_mutex);
107 
108         if (enable_accessory) {
109             struct usb_descriptor_header* desc;
110             struct usb_descriptor_iter iter;
111             struct usb_interface_descriptor *intf = NULL;
112             struct usb_endpoint_descriptor *ep1 = NULL;
113             struct usb_endpoint_descriptor *ep2 = NULL;
114             pthread_t th;
115 
116             usb_descriptor_iter_init(device, &iter);
117             while ((desc = usb_descriptor_iter_next(&iter)) != NULL && (!intf || !ep1 || !ep2)) {
118                 if (desc->bDescriptorType == USB_DT_INTERFACE) {
119                     intf = (struct usb_interface_descriptor *)desc;
120                 } else if (desc->bDescriptorType == USB_DT_ENDPOINT) {
121                     if (ep1)
122                         ep2 = (struct usb_endpoint_descriptor *)desc;
123                     else
124                         ep1 = (struct usb_endpoint_descriptor *)desc;
125                 }
126             }
127 
128             if (!intf) {
129                 fprintf(stderr, "interface not found\n");
130                 exit(1);
131             }
132             if (!ep1 || !ep2) {
133                 fprintf(stderr, "endpoints not found\n");
134                 exit(1);
135             }
136 
137             if (usb_device_claim_interface(device, intf->bInterfaceNumber)) {
138                 fprintf(stderr, "usb_device_claim_interface failed errno: %d\n", errno);
139                 exit(1);
140             }
141 
142             if ((ep1->bEndpointAddress & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN) {
143                 read_ep = ep1->bEndpointAddress;
144                 write_ep = ep2->bEndpointAddress;
145             } else {
146                 read_ep = ep2->bEndpointAddress;
147                 write_ep = ep1->bEndpointAddress;
148             }
149 
150             pthread_create(&th, NULL, read_thread, NULL);
151             pthread_create(&th, NULL, write_thread, NULL);
152         }
153     } else {
154 //        fprintf(stderr, "Found new device - attempting to switch to accessory mode\n");
155 
156         uint16_t protocol = -1;
157         ret = usb_device_control_transfer(device, USB_DIR_IN | USB_TYPE_VENDOR,
158                 ACCESSORY_GET_PROTOCOL, 0, 0, &protocol, sizeof(protocol), 1000);
159         if (ret < 0) {
160  //           fprintf(stderr, "ACCESSORY_GET_PROTOCOL returned %d errno: %d\n", ret, errno);
161         } else {
162             fprintf(stderr, "device supports protocol version %d\n", protocol);
163             if (protocol >= 2) {
164                 if (enable_accessory) {
165                     send_string(device, ACCESSORY_STRING_MANUFACTURER, "Google, Inc.");
166                     send_string(device, ACCESSORY_STRING_MODEL, "AccessoryChat");
167                     send_string(device, ACCESSORY_STRING_DESCRIPTION, "Accessory Chat");
168                     send_string(device, ACCESSORY_STRING_VERSION, "1.0");
169                     send_string(device, ACCESSORY_STRING_URI, "http://www.android.com");
170                     send_string(device, ACCESSORY_STRING_SERIAL, "1234567890");
171                 }
172 
173                 fprintf(stderr, "sending ACCESSORY_SET_AUDIO_MODE\n");
174                 ret = usb_device_control_transfer(device, USB_DIR_OUT | USB_TYPE_VENDOR,
175                         ACCESSORY_SET_AUDIO_MODE, 1, 0, NULL, 0, 1000);
176                 if (ret < 0)
177                     fprintf(stderr, "ACCESSORY_SET_AUDIO_MODE returned %d errno: %d\n", ret, errno);
178 
179                 fprintf(stderr, "sending ACCESSORY_START\n");
180                 ret = usb_device_control_transfer(device, USB_DIR_OUT | USB_TYPE_VENDOR,
181                         ACCESSORY_START, 0, 0, NULL, 0, 1000);
182                 fprintf(stderr, "did ACCESSORY_START\n");
183                 if (ret < 0)
184                     fprintf(stderr, "ACCESSORY_START returned %d errno: %d\n", ret, errno);
185             }
186         }
187 
188         return 0;
189     }
190 
191     if (device != current_device)
192         usb_device_close(device);
193 
194     return 0;
195 }
196 
usb_device_removed(const char * devname,void * client_data)197 static int usb_device_removed(const char *devname, void* client_data) {
198     pthread_mutex_lock(&device_mutex);
199 
200     if (current_device && !strcmp(usb_device_get_name(current_device), devname)) {
201         fprintf(stderr, "current device disconnected\n");
202         usb_device_close(current_device);
203         current_device = NULL;
204     }
205 
206     pthread_mutex_unlock(&device_mutex);
207     return 0;
208 }
209 
usb_wait_for_device()210 struct usb_device* usb_wait_for_device() {
211     struct usb_device* device = NULL;
212 
213     pthread_mutex_lock(&device_mutex);
214     while (!current_device)
215          pthread_cond_wait(&device_cond, &device_mutex);
216     device = current_device;
217     pthread_mutex_unlock(&device_mutex);
218 
219     return device;
220 }
221 
usb_run(int enable_accessory)222 void usb_run(int enable_accessory) {
223     struct usb_host_context* context = usb_host_init();
224 
225     usb_host_run(context, usb_device_added, usb_device_removed, NULL, (void *)enable_accessory);
226 }
227 
228