hw/usb.c

   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
  29 void usb_attach(USBPort *port, USBDevice *dev)
  30 {
  31     if (dev != NULL) {
  32         /* attach */
  33         if (port->dev) {
  34             usb_attach(port, NULL);
  35         }
  36         dev->port = port;
  37         port->dev = dev;
  38         port->ops->attach(port);
  39         usb_send_msg(dev, USB_MSG_ATTACH);
  40     } else {
  41         /* detach */
  42         dev = port->dev;
  43         port->ops->detach(port);
  44         if (dev) {
  45             usb_send_msg(dev, USB_MSG_DETACH);
  46             dev->port = NULL;
  47             port->dev = NULL;
  48         }
  49     }
  50 }
  51
  52 void usb_wakeup(USBDevice *dev)
  53 {
  54     if (dev->remote_wakeup && dev->port && dev->port->ops->wakeup) {
  55         dev->port->ops->wakeup(dev);
  56     }
  57 }
  58
  59 /**********************/
  60
  61 /* generic USB device helpers (you are not forced to use them when
  62    writing your USB device driver, but they help handling the
  63    protocol)
  64 */
  65
  66 #define SETUP_STATE_IDLE  0
  67 #define SETUP_STATE_SETUP 1
  68 #define SETUP_STATE_DATA  2
  69 #define SETUP_STATE_ACK   3
  70
  71 static int do_token_setup(USBDevice *s, USBPacket *p)
  72 {
  73     int request, value, index;
  74     int ret = 0;
  75
  76     if (p->len != 8)
  77         return USB_RET_STALL;
  78
  79     memcpy(s->setup_buf, p->data, 8);
  80     s->setup_len   = (s->setup_buf[7] << 8) | s->setup_buf[6];
  81     s->setup_index = 0;
  82
  83     request = (s->setup_buf[0] << 8) | s->setup_buf[1];
  84     value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
  85     index   = (s->setup_buf[5] << 8) | s->setup_buf[4];
  86
  87     if (s->setup_buf[0] & USB_DIR_IN) {
  88         ret = s->info->handle_control(s, p, request, value, index,
  89                                       s->setup_len, s->data_buf);
  90         if (ret == USB_RET_ASYNC) {
  91              s->setup_state = SETUP_STATE_SETUP;
  92              return USB_RET_ASYNC;
  93         }
  94         if (ret < 0)
  95             return ret;
  96
  97         if (ret < s->setup_len)
  98             s->setup_len = ret;
  99         s->setup_state = SETUP_STATE_DATA;
 100     } else {
 101         if (s->setup_len > sizeof(s->data_buf)) {
 102             fprintf(stderr,
 103                 "usb_generic_handle_packet: ctrl buffer too small (%d > %zu)\n",
 104                 s->setup_len, sizeof(s->data_buf));
 105             return USB_RET_STALL;
 106         }
 107         if (s->setup_len == 0)
 108             s->setup_state = SETUP_STATE_ACK;
 109         else
 110             s->setup_state = SETUP_STATE_DATA;
 111     }
 112
 113     return ret;
 114 }
 115
 116 static int do_token_in(USBDevice *s, USBPacket *p)
 117 {
 118     int request, value, index;
 119     int ret = 0;
 120
 121     if (p->devep != 0)
 122         return s->info->handle_data(s, p);
 123
 124     request = (s->setup_buf[0] << 8) | s->setup_buf[1];
 125     value   = (s->setup_buf[3] << 8) | s->setup_buf[2];
 126     index   = (s->setup_buf[5] << 8) | s->setup_buf[4];
 127
 128     switch(s->setup_state) {
 129     case SETUP_STATE_ACK:
 130         if (!(s->setup_buf[0] & USB_DIR_IN)) {
 131             ret = s->info->handle_control(s, p, request, value, index,
 132                                           s->setup_len, s->data_buf);
 133             if (ret == USB_RET_ASYNC) {
 134                 return USB_RET_ASYNC;
 135             }
 136             s->setup_state = SETUP_STATE_IDLE;
 137             if (ret > 0)
 138                 return 0;
 139             return ret;
 140         }
 141
 142         /* return 0 byte */
 143         return 0;
 144
 145     case SETUP_STATE_DATA:
 146         if (s->setup_buf[0] & USB_DIR_IN) {
 147             int len = s->setup_len - s->setup_index;
 148             if (len > p->len)
 149                 len = p->len;
 150             memcpy(p->data, s->data_buf + s->setup_index, len);
 151             s->setup_index += len;
 152             if (s->setup_index >= s->setup_len)
 153                 s->setup_state = SETUP_STATE_ACK;
 154             return len;
 155         }
 156
 157         s->setup_state = SETUP_STATE_IDLE;
 158         return USB_RET_STALL;
 159
 160     default:
 161         return USB_RET_STALL;
 162     }
 163 }
 164
 165 static int do_token_out(USBDevice *s, USBPacket *p)
 166 {
 167     if (p->devep != 0)
 168         return s->info->handle_data(s, p);
 169
 170     switch(s->setup_state) {
 171     case SETUP_STATE_ACK:
 172         if (s->setup_buf[0] & USB_DIR_IN) {
 173             s->setup_state = SETUP_STATE_IDLE;
 174             /* transfer OK */
 175         } else {
 176             /* ignore additional output */
 177         }
 178         return 0;
 179
 180     case SETUP_STATE_DATA:
 181         if (!(s->setup_buf[0] & USB_DIR_IN)) {
 182             int len = s->setup_len - s->setup_index;
 183             if (len > p->len)
 184                 len = p->len;
 185             memcpy(s->data_buf + s->setup_index, p->data, len);
 186             s->setup_index += len;
 187             if (s->setup_index >= s->setup_len)
 188                 s->setup_state = SETUP_STATE_ACK;
 189             return len;
 190         }
 191
 192         s->setup_state = SETUP_STATE_IDLE;
 193         return USB_RET_STALL;
 194
 195     default:
 196         return USB_RET_STALL;
 197     }
 198 }
 199
 200 /*
 201  * Generic packet handler.
 202  * Called by the HC (host controller).
 203  *
 204  * Returns length of the transaction or one of the USB_RET_XXX codes.
 205  */
 206 int usb_generic_handle_packet(USBDevice *s, USBPacket *p)
 207 {
 208     switch(p->pid) {
 209     case USB_MSG_ATTACH:
 210         s->state = USB_STATE_ATTACHED;
 211         if (s->info->handle_attach) {
 212             s->info->handle_attach(s);
 213         }
 214         return 0;
 215
 216     case USB_MSG_DETACH:
 217         s->state = USB_STATE_NOTATTACHED;
 218         return 0;
 219
 220     case USB_MSG_RESET:
 221         s->remote_wakeup = 0;
 222         s->addr = 0;
 223         s->state = USB_STATE_DEFAULT;
 224         if (s->info->handle_reset) {
 225             s->info->handle_reset(s);
 226         }
 227         return 0;
 228     }
 229
 230     /* Rest of the PIDs must match our address */
 231     if (s->state < USB_STATE_DEFAULT || p->devaddr != s->addr)
 232         return USB_RET_NODEV;
 233
 234     switch (p->pid) {
 235     case USB_TOKEN_SETUP:
 236         return do_token_setup(s, p);
 237
 238     case USB_TOKEN_IN:
 239         return do_token_in(s, p);
 240
 241     case USB_TOKEN_OUT:
 242         return do_token_out(s, p);
 243
 244     default:
 245         return USB_RET_STALL;
 246     }
 247 }
 248
 249 /* ctrl complete function for devices which use usb_generic_handle_packet and
 250    may return USB_RET_ASYNC from their handle_control callback. Device code
 251    which does this *must* call this function instead of the normal
 252    usb_packet_complete to complete their async control packets. */
 253 void usb_generic_async_ctrl_complete(USBDevice *s, USBPacket *p)
 254 {
 255     if (p->len < 0) {
 256         s->setup_state = SETUP_STATE_IDLE;
 257     }
 258
 259     switch (s->setup_state) {
 260     case SETUP_STATE_SETUP:
 261         if (p->len < s->setup_len) {
 262             s->setup_len = p->len;
 263         }
 264         s->setup_state = SETUP_STATE_DATA;
 265         p->len = 8;
 266         break;
 267
 268     case SETUP_STATE_ACK:
 269         s->setup_state = SETUP_STATE_IDLE;
 270         p->len = 0;
 271         break;
 272
 273     default:
 274         break;
 275     }
 276     usb_packet_complete(s, p);
 277 }
 278
 279 /* XXX: fix overflow */
 280 int set_usb_string(uint8_t *buf, const char *str)
 281 {
 282     int len, i;
 283     uint8_t *q;
 284
 285     q = buf;
 286     len = strlen(str);
 287     *q++ = 2 * len + 2;
 288     *q++ = 3;
 289     for(i = 0; i < len; i++) {
 290         *q++ = str[i];
 291         *q++ = 0;
 292     }
 293     return q - buf;
 294 }
 295
 296 /* Send an internal message to a USB device.  */
 297 void usb_send_msg(USBDevice *dev, int msg)
 298 {
 299     USBPacket p;
 300     int ret;
 301
 302     memset(&p, 0, sizeof(p));
 303     p.pid = msg;
 304     ret = usb_handle_packet(dev, &p);
 305     /* This _must_ be synchronous */
 306     assert(ret != USB_RET_ASYNC);
 307 }
 308
 309 /* Hand over a packet to a device for processing.  Return value
 310    USB_RET_ASYNC indicates the processing isn't finished yet, the
 311    driver will call usb_packet_complete() when done processing it. */
 312 int usb_handle_packet(USBDevice *dev, USBPacket *p)
 313 {
 314     int ret;
 315
 316     ret = dev->info->handle_packet(dev, p);
 317     return ret;
 318 }