aboutsummaryrefslogtreecommitdiff
path: root/hw/usb.c
blob: 4a39cbcc7d2e609b2844b64eeefb69dab400c11c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
/*
 * QEMU USB emulation
 *
 * Copyright (c) 2005 Fabrice Bellard
 *
 * 2008 Generic packet handler rewrite by Max Krasnyansky
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "qemu-common.h"
#include "usb.h"

void usb_attach(USBPort *port, USBDevice *dev)
{
    if (dev != NULL) {
        /* attach */
        if (port->dev) {
            usb_attach(port, NULL);
        }
        dev->port = port;
        port->dev = dev;
        port->ops->attach(port);
        usb_send_msg(dev, USB_MSG_ATTACH);
    } else {
        /* detach */
        dev = port->dev;
        port->ops->detach(port);
        if (dev) {
            usb_send_msg(dev, USB_MSG_DETACH);
            dev->port = NULL;
            port->dev = NULL;
        }
    }
}

void usb_wakeup(USBDevice *dev)
{
    if (dev->remote_wakeup && dev->port && dev->port->ops->wakeup) {
        dev->port->ops->wakeup(dev);
    }
}

/**********************/

/* generic USB device helpers (you are not forced to use them when
   writing your USB device driver, but they help handling the
   protocol)
*/

#define SETUP_STATE_IDLE  0
#define SETUP_STATE_SETUP 1
#define SETUP_STATE_DATA  2
#define SETUP_STATE_ACK   3

static int do_token_setup(USBDevice *s, USBPacket *p)
{
    int request, value, index;
    int ret = 0;

    if (p->len != 8)
        return USB_RET_STALL;
 
    memcpy(s->setup_buf, p->data, 8);
    s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];
    s->setup_index = 0;

    request = (s->setup_buf[0] << 8) | s->setup_buf[1];
    value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
    index   = (s->setup_buf[5] << 8) | s->setup_buf[4];

    if (s->setup_buf[0] & USB_DIR_IN) {
        ret = s->info->handle_control(s, p, request, value, index,
                                      s->setup_len, s->data_buf);
        if (ret == USB_RET_ASYNC) {
             s->setup_state = SETUP_STATE_SETUP;
             return USB_RET_ASYNC;
        }
        if (ret < 0)
            return ret;

        if (ret < s->setup_len)
            s->setup_len = ret;
        s->setup_state = SETUP_STATE_DATA;
    } else {
        if (s->setup_len > sizeof(s->data_buf)) {
            fprintf(stderr,
                "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",
                s->setup_len, sizeof(s->data_buf));
            return USB_RET_STALL;
        }
        if (s->setup_len == 0)
            s->setup_state = SETUP_STATE_ACK;
        else
            s->setup_state = SETUP_STATE_DATA;
    }

    return ret;
}

static int do_token_in(USBDevice *s, USBPacket *p)
{
    int request, value, index;
    int ret = 0;

    if (p->devep != 0)
        return s->info->handle_data(s, p);

    request = (s->setup_buf[0] << 8) | s->setup_buf[1];
    value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
    index   = (s->setup_buf[5] << 8) | s->setup_buf[4];
 
    switch(s->setup_state) {
    case SETUP_STATE_ACK:
        if (!(s->setup_buf[0] & USB_DIR_IN)) {
            ret = s->info->handle_control(s, p, request, value, index,
                                          s->setup_len, s->data_buf);
            if (ret == USB_RET_ASYNC) {
                return USB_RET_ASYNC;
            }
            s->setup_state = SETUP_STATE_IDLE;
            if (ret > 0)
                return 0;
            return ret;
        }

        /* return 0 byte */
        return 0;

    case SETUP_STATE_DATA:
        if (s->setup_buf[0] & USB_DIR_IN) {
            int len = s->setup_len - s->setup_index;
            if (len > p->len)
                len = p->len;
            memcpy(p->data, s->data_buf + s->setup_index, len);
            s->setup_index += len;
            if (s->setup_index >= s->setup_len)
                s->setup_state = SETUP_STATE_ACK;
            return len;
        }

        s->setup_state = SETUP_STATE_IDLE;
        return USB_RET_STALL;

    default:
        return USB_RET_STALL;
    }
}

static int do_token_out(USBDevice *s, USBPacket *p)
{
    if (p->devep != 0)
        return s->info->handle_data(s, p);

    switch(s->setup_state) {
    case SETUP_STATE_ACK:
        if (s->setup_buf[0] & USB_DIR_IN) {
            s->setup_state = SETUP_STATE_IDLE;
            /* transfer OK */
        } else {
            /* ignore additional output */
        }
        return 0;

    case SETUP_STATE_DATA:
        if (!(s->setup_buf[0] & USB_DIR_IN)) {
            int len = s->setup_len - s->setup_index;
            if (len > p->len)
                len = p->len;
            memcpy(s->data_buf + s->setup_index, p->data, len);
            s->setup_index += len;
            if (s->setup_index >= s->setup_len)
                s->setup_state = SETUP_STATE_ACK;
            return len;
        }

        s->setup_state = SETUP_STATE_IDLE;
        return USB_RET_STALL;

    default:
        return USB_RET_STALL;
    }
}

/*
 * Generic packet handler.
 * Called by the HC (host controller).
 *
 * Returns length of the transaction or one of the USB_RET_XXX codes.
 */
int usb_generic_handle_packet(USBDevice *s, USBPacket *p)
{
    switch(p->pid) {
    case USB_MSG_ATTACH:
        s->state = USB_STATE_ATTACHED;
        if (s->info->handle_attach) {
            s->info->handle_attach(s);
        }
        return 0;

    case USB_MSG_DETACH:
        s->state = USB_STATE_NOTATTACHED;
        return 0;

    case USB_MSG_RESET:
        s->remote_wakeup = 0;
        s->addr = 0;
        s->state = USB_STATE_DEFAULT;
        if (s->info->handle_reset) {
            s->info->handle_reset(s);
        }
        return 0;
    }

    /* Rest of the PIDs must match our address */
    if (s->state < USB_STATE_DEFAULT || p->devaddr != s->addr)
        return USB_RET_NODEV;

    switch (p->pid) {
    case USB_TOKEN_SETUP:
        return do_token_setup(s, p);

    case USB_TOKEN_IN:
        return do_token_in(s, p);

    case USB_TOKEN_OUT:
        return do_token_out(s, p);
 
    default:
        return USB_RET_STALL;
    }
}

/* ctrl complete function for devices which use usb_generic_handle_packet and
   may return USB_RET_ASYNC from their handle_control callback. Device code
   which does this *must* call this function instead of the normal
   usb_packet_complete to complete their async control packets. */
void usb_generic_async_ctrl_complete(USBDevice *s, USBPacket *p)
{
    if (p->len < 0) {
        s->setup_state = SETUP_STATE_IDLE;
    }

    switch (s->setup_state) {
    case SETUP_STATE_SETUP:
        if (p->len < s->setup_len) {
            s->setup_len = p->len;
        }
        s->setup_state = SETUP_STATE_DATA;
        p->len = 8;
        break;

    case SETUP_STATE_ACK:
        s->setup_state = SETUP_STATE_IDLE;
        p->len = 0;
        break;

    default:
        break;
    }
    usb_packet_complete(s, p);
}

/* XXX: fix overflow */
int set_usb_string(uint8_t *buf, const char *str)
{
    int len, i;
    uint8_t *q;

    q = buf;
    len = strlen(str);
    *q++ = 2 * len + 2;
    *q++ = 3;
    for(i = 0; i < len; i++) {
        *q++ = str[i];
        *q++ = 0;
    }
    return q - buf;
}

/* Send an internal message to a USB device.  */
void usb_send_msg(USBDevice *dev, int msg)
{
    USBPacket p;
    int ret;

    memset(&p, 0, sizeof(p));
    p.pid = msg;
    ret = usb_handle_packet(dev, &p);
    /* This _must_ be synchronous */
    assert(ret != USB_RET_ASYNC);
}

/* Hand over a packet to a device for processing.  Return value
   USB_RET_ASYNC indicates the processing isn't finished yet, the
   driver will call usb_packet_complete() when done processing it. */
int usb_handle_packet(USBDevice *dev, USBPacket *p)
{
    int ret;

    assert(p->owner == NULL);
    ret = dev->info->handle_packet(dev, p);
    if (ret == USB_RET_ASYNC) {
        if (p->owner == NULL) {
            p->owner = dev;
        } else {
            /* We'll end up here when usb_handle_packet is called
             * recursively due to a hub being in the chain.  Nothing
             * to do.  Leave p->owner pointing to the device, not the
             * hub. */;
        }
    }
    return ret;
}

/* Notify the controller that an async packet is complete.  This should only
   be called for packets previously deferred by returning USB_RET_ASYNC from
   handle_packet. */
void usb_packet_complete(USBDevice *dev, USBPacket *p)
{
    /* Note: p->owner != dev is possible in case dev is a hub */
    assert(p->owner != NULL);
    dev->port->ops->complete(dev, p);
    p->owner = NULL;
}

/* Cancel an active packet.  The packed must have been deferred by
   returning USB_RET_ASYNC from handle_packet, and not yet
   completed.  */
void usb_cancel_packet(USBPacket * p)
{
    assert(p->owner != NULL);
    p->owner->info->cancel_packet(p->owner, p);
    p->owner = NULL;
}