• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * QEMU USB emulation
3  *
4  * Copyright (c) 2005 Fabrice Bellard
5  *
6  * 2008 Generic packet handler rewrite by Max Krasnyansky
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a copy
9  * of this software and associated documentation files (the "Software"), to deal
10  * in the Software without restriction, including without limitation the rights
11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12  * copies of the Software, and to permit persons to whom the Software is
13  * furnished to do so, subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be included in
16  * all copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24  * THE SOFTWARE.
25  */
26 #include "qemu-common.h"
27 #include "usb.h"
28 
usb_attach(USBPort * port,USBDevice * dev)29 void usb_attach(USBPort *port, USBDevice *dev)
30 {
31     port->attach(port, dev);
32 }
33 
34 /**********************/
35 
36 /* generic USB device helpers (you are not forced to use them when
37    writing your USB device driver, but they help handling the
38    protocol)
39 */
40 
41 #define SETUP_STATE_IDLE 0
42 #define SETUP_STATE_DATA 1
43 #define SETUP_STATE_ACK  2
44 
do_token_setup(USBDevice * s,USBPacket * p)45 static int do_token_setup(USBDevice *s, USBPacket *p)
46 {
47     int request, value, index;
48     int ret = 0;
49 
50     if (p->len != 8)
51         return USB_RET_STALL;
52 
53     memcpy(s->setup_buf, p->data, 8);
54     s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];
55     s->setup_index = 0;
56 
57     request = (s->setup_buf[0] << 8) | s->setup_buf[1];
58     value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
59     index   = (s->setup_buf[5] << 8) | s->setup_buf[4];
60 
61     if (s->setup_buf[0] & USB_DIR_IN) {
62         ret = s->handle_control(s, request, value, index,
63                                 s->setup_len, s->data_buf);
64         if (ret < 0)
65             return ret;
66 
67         if (ret < s->setup_len)
68             s->setup_len = ret;
69         s->setup_state = SETUP_STATE_DATA;
70     } else {
71         if (s->setup_len == 0)
72             s->setup_state = SETUP_STATE_ACK;
73         else
74             s->setup_state = SETUP_STATE_DATA;
75     }
76 
77     return ret;
78 }
79 
do_token_in(USBDevice * s,USBPacket * p)80 static int do_token_in(USBDevice *s, USBPacket *p)
81 {
82     int request, value, index;
83     int ret = 0;
84 
85     if (p->devep != 0)
86         return s->handle_data(s, p);
87 
88     request = (s->setup_buf[0] << 8) | s->setup_buf[1];
89     value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
90     index   = (s->setup_buf[5] << 8) | s->setup_buf[4];
91 
92     switch(s->setup_state) {
93     case SETUP_STATE_ACK:
94         if (!(s->setup_buf[0] & USB_DIR_IN)) {
95             s->setup_state = SETUP_STATE_IDLE;
96             ret = s->handle_control(s, request, value, index,
97                                     s->setup_len, s->data_buf);
98             if (ret > 0)
99                 return 0;
100             return ret;
101         }
102 
103         /* return 0 byte */
104         return 0;
105 
106     case SETUP_STATE_DATA:
107         if (s->setup_buf[0] & USB_DIR_IN) {
108             int len = s->setup_len - s->setup_index;
109             if (len > p->len)
110                 len = p->len;
111             memcpy(p->data, s->data_buf + s->setup_index, len);
112             s->setup_index += len;
113             if (s->setup_index >= s->setup_len)
114                 s->setup_state = SETUP_STATE_ACK;
115             return len;
116         }
117 
118         s->setup_state = SETUP_STATE_IDLE;
119         return USB_RET_STALL;
120 
121     default:
122         return USB_RET_STALL;
123     }
124 }
125 
do_token_out(USBDevice * s,USBPacket * p)126 static int do_token_out(USBDevice *s, USBPacket *p)
127 {
128     if (p->devep != 0)
129         return s->handle_data(s, p);
130 
131     switch(s->setup_state) {
132     case SETUP_STATE_ACK:
133         if (s->setup_buf[0] & USB_DIR_IN) {
134             s->setup_state = SETUP_STATE_IDLE;
135             /* transfer OK */
136         } else {
137             /* ignore additional output */
138         }
139         return 0;
140 
141     case SETUP_STATE_DATA:
142         if (!(s->setup_buf[0] & USB_DIR_IN)) {
143             int len = s->setup_len - s->setup_index;
144             if (len > p->len)
145                 len = p->len;
146             memcpy(s->data_buf + s->setup_index, p->data, len);
147             s->setup_index += len;
148             if (s->setup_index >= s->setup_len)
149                 s->setup_state = SETUP_STATE_ACK;
150             return len;
151         }
152 
153         s->setup_state = SETUP_STATE_IDLE;
154         return USB_RET_STALL;
155 
156     default:
157         return USB_RET_STALL;
158     }
159 }
160 
161 /*
162  * Generic packet handler.
163  * Called by the HC (host controller).
164  *
165  * Returns length of the transaction or one of the USB_RET_XXX codes.
166  */
usb_generic_handle_packet(USBDevice * s,USBPacket * p)167 int usb_generic_handle_packet(USBDevice *s, USBPacket *p)
168 {
169     switch(p->pid) {
170     case USB_MSG_ATTACH:
171         s->state = USB_STATE_ATTACHED;
172         return 0;
173 
174     case USB_MSG_DETACH:
175         s->state = USB_STATE_NOTATTACHED;
176         return 0;
177 
178     case USB_MSG_RESET:
179         s->remote_wakeup = 0;
180         s->addr = 0;
181         s->state = USB_STATE_DEFAULT;
182         s->handle_reset(s);
183         return 0;
184     }
185 
186     /* Rest of the PIDs must match our address */
187     if (s->state < USB_STATE_DEFAULT || p->devaddr != s->addr)
188         return USB_RET_NODEV;
189 
190     switch (p->pid) {
191     case USB_TOKEN_SETUP:
192         return do_token_setup(s, p);
193 
194     case USB_TOKEN_IN:
195         return do_token_in(s, p);
196 
197     case USB_TOKEN_OUT:
198         return do_token_out(s, p);
199 
200     default:
201         return USB_RET_STALL;
202     }
203 }
204 
205 /* XXX: fix overflow */
set_usb_string(uint8_t * buf,const char * str)206 int set_usb_string(uint8_t *buf, const char *str)
207 {
208     int len, i;
209     uint8_t *q;
210 
211     q = buf;
212     len = strlen(str);
213     *q++ = 2 * len + 2;
214     *q++ = 3;
215     for(i = 0; i < len; i++) {
216         *q++ = str[i];
217         *q++ = 0;
218     }
219     return q - buf;
220 }
221 
222 /* Send an internal message to a USB device.  */
usb_send_msg(USBDevice * dev,int msg)223 void usb_send_msg(USBDevice *dev, int msg)
224 {
225     USBPacket p;
226     memset(&p, 0, sizeof(p));
227     p.pid = msg;
228     dev->handle_packet(dev, &p);
229 
230     /* This _must_ be synchronous */
231 }
232