sys/dev/usb/misc/udbp.c

   1 /*-
   2  * Copyright (c) 1996-2000 Whistle Communications, Inc.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of author nor the names of its
  14  *    contributors may be used to endorse or promote products derived
  15  *    from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY NICK HIBMA AND CONTRIBUTORS
  18  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  19  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
  21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  26  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  27  * POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  */
  30
  31 #include <sys/cdefs.h>
  32 __FBSDID("$FreeBSD$");
  33
  34 /* Driver for arbitrary double bulk pipe devices.
  35  * The driver assumes that there will be the same driver on the other side.
  36  *
  37  * XXX Some more information on what the framing of the IP packets looks like.
  38  *
  39  * To take full advantage of bulk transmission, packets should be chosen
  40  * between 1k and 5k in size (1k to make sure the sending side starts
  41  * streaming, and <5k to avoid overflowing the system with small TDs).
  42  */
  43
  44
  45 /* probe/attach/detach:
  46  *  Connect the driver to the hardware and netgraph
  47  *
  48  *  The reason we submit a bulk in transfer is that USB does not know about
  49  *  interrupts. The bulk transfer continuously polls the device for data.
  50  *  While the device has no data available, the device NAKs the TDs. As soon
  51  *  as there is data, the transfer happens and the data comes flowing in.
  52  *
  53  *  In case you were wondering, interrupt transfers happen exactly that way.
  54  *  It therefore doesn't make sense to use the interrupt pipe to signal
  55  *  'data ready' and then schedule a bulk transfer to fetch it. That would
  56  *  incur a 2ms delay at least, without reducing bandwidth requirements.
  57  *
  58  */
  59
  60 #include <sys/stdint.h>
  61 #include <sys/stddef.h>
  62 #include <sys/param.h>
  63 #include <sys/queue.h>
  64 #include <sys/types.h>
  65 #include <sys/systm.h>
  66 #include <sys/kernel.h>
  67 #include <sys/bus.h>
  68 #include <sys/module.h>
  69 #include <sys/lock.h>
  70 #include <sys/mutex.h>
  71 #include <sys/condvar.h>
  72 #include <sys/sysctl.h>
  73 #include <sys/sx.h>
  74 #include <sys/unistd.h>
  75 #include <sys/callout.h>
  76 #include <sys/malloc.h>
  77 #include <sys/priv.h>
  78
  79 #include <dev/usb/usb.h>
  80 #include <dev/usb/usbdi.h>
  81 #include <dev/usb/usbdi_util.h>
  82 #include "usbdevs.h"
  83
  84 #define USB_DEBUG_VAR udbp_debug
  85 #include <dev/usb/usb_debug.h>
  86
  87 #include <sys/mbuf.h>
  88
  89 #include <netgraph/ng_message.h>
  90 #include <netgraph/netgraph.h>
  91 #include <netgraph/ng_parse.h>
  92 #include <netgraph/bluetooth/include/ng_bluetooth.h>
  93
  94 #include <dev/usb/misc/udbp.h>
  95
  96 #ifdef USB_DEBUG
  97 static int udbp_debug = 0;
  98
  99 static SYSCTL_NODE(_hw_usb, OID_AUTO, udbp, CTLFLAG_RW, 0, "USB udbp");
 100 SYSCTL_INT(_hw_usb_udbp, OID_AUTO, debug, CTLFLAG_RW,
 101     &udbp_debug, 0, "udbp debug level");
 102 #endif
 103
 104 #define UDBP_TIMEOUT    2000            /* timeout on outbound transfers, in
 105                                          * msecs */
 106 #define UDBP_BUFFERSIZE MCLBYTES        /* maximum number of bytes in one
 107                                          * transfer */
 108 #define UDBP_T_WR       0
 109 #define UDBP_T_RD       1
 110 #define UDBP_T_WR_CS    2
 111 #define UDBP_T_RD_CS    3
 112 #define UDBP_T_MAX      4
 113 #define UDBP_Q_MAXLEN   50
 114
 115 struct udbp_softc {
 116
 117         struct mtx sc_mtx;
 118         struct ng_bt_mbufq sc_xmitq_hipri;      /* hi-priority transmit queue */
 119         struct ng_bt_mbufq sc_xmitq;    /* low-priority transmit queue */
 120
 121         struct usb_xfer *sc_xfer[UDBP_T_MAX];
 122         node_p  sc_node;                /* back pointer to node */
 123         hook_p  sc_hook;                /* pointer to the hook */
 124         struct mbuf *sc_bulk_in_buffer;
 125
 126         uint32_t sc_packets_in;         /* packets in from downstream */
 127         uint32_t sc_packets_out;        /* packets out towards downstream */
 128
 129         uint8_t sc_flags;
 130 #define UDBP_FLAG_READ_STALL    0x01    /* read transfer stalled */
 131 #define UDBP_FLAG_WRITE_STALL   0x02    /* write transfer stalled */
 132
 133         uint8_t sc_name[16];
 134 };
 135
 136 /* prototypes */
 137
 138 static int udbp_modload(module_t mod, int event, void *data);
 139
 140 static device_probe_t udbp_probe;
 141 static device_attach_t udbp_attach;
 142 static device_detach_t udbp_detach;
 143
 144 static usb_callback_t udbp_bulk_read_callback;
 145 static usb_callback_t udbp_bulk_read_clear_stall_callback;
 146 static usb_callback_t udbp_bulk_write_callback;
 147 static usb_callback_t udbp_bulk_write_clear_stall_callback;
 148
 149 static void     udbp_bulk_read_complete(node_p, hook_p, void *, int);
 150
 151 static ng_constructor_t ng_udbp_constructor;
 152 static ng_rcvmsg_t      ng_udbp_rcvmsg;
 153 static ng_shutdown_t    ng_udbp_rmnode;
 154 static ng_newhook_t     ng_udbp_newhook;
 155 static ng_connect_t     ng_udbp_connect;
 156 static ng_rcvdata_t     ng_udbp_rcvdata;
 157 static ng_disconnect_t  ng_udbp_disconnect;
 158
 159 /* Parse type for struct ngudbpstat */
 160 static const struct ng_parse_struct_field
 161         ng_udbp_stat_type_fields[] = NG_UDBP_STATS_TYPE_INFO;
 162
 163 static const struct ng_parse_type ng_udbp_stat_type = {
 164         &ng_parse_struct_type,
 165         &ng_udbp_stat_type_fields
 166 };
 167
 168 /* List of commands and how to convert arguments to/from ASCII */
 169 static const struct ng_cmdlist ng_udbp_cmdlist[] = {
 170         {
 171                 NGM_UDBP_COOKIE,
 172                 NGM_UDBP_GET_STATUS,
 173                 "getstatus",
 174                 NULL,
 175                 &ng_udbp_stat_type,
 176         },
 177         {
 178                 NGM_UDBP_COOKIE,
 179                 NGM_UDBP_SET_FLAG,
 180                 "setflag",
 181                 &ng_parse_int32_type,
 182                 NULL
 183         },
 184         {0}
 185 };
 186
 187 /* Netgraph node type descriptor */
 188 static struct ng_type ng_udbp_typestruct = {
 189         .version = NG_ABI_VERSION,
 190         .name = NG_UDBP_NODE_TYPE,
 191         .constructor = ng_udbp_constructor,
 192         .rcvmsg = ng_udbp_rcvmsg,
 193         .shutdown = ng_udbp_rmnode,
 194         .newhook = ng_udbp_newhook,
 195         .connect = ng_udbp_connect,
 196         .rcvdata = ng_udbp_rcvdata,
 197         .disconnect = ng_udbp_disconnect,
 198         .cmdlist = ng_udbp_cmdlist,
 199 };
 200
 201 /* USB config */
 202 static const struct usb_config udbp_config[UDBP_T_MAX] = {
 203
 204         [UDBP_T_WR] = {
 205                 .type = UE_BULK,
 206                 .endpoint = UE_ADDR_ANY,
 207                 .direction = UE_DIR_OUT,
 208                 .bufsize = UDBP_BUFFERSIZE,
 209                 .flags = {.pipe_bof = 1,.force_short_xfer = 1,},
 210                 .callback = &udbp_bulk_write_callback,
 211                 .timeout = UDBP_TIMEOUT,
 212         },
 213
 214         [UDBP_T_RD] = {
 215                 .type = UE_BULK,
 216                 .endpoint = UE_ADDR_ANY,
 217                 .direction = UE_DIR_IN,
 218                 .bufsize = UDBP_BUFFERSIZE,
 219                 .flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
 220                 .callback = &udbp_bulk_read_callback,
 221         },
 222
 223         [UDBP_T_WR_CS] = {
 224                 .type = UE_CONTROL,
 225                 .endpoint = 0x00,       /* Control pipe */
 226                 .direction = UE_DIR_ANY,
 227                 .bufsize = sizeof(struct usb_device_request),
 228                 .callback = &udbp_bulk_write_clear_stall_callback,
 229                 .timeout = 1000,        /* 1 second */
 230                 .interval = 50, /* 50ms */
 231         },
 232
 233         [UDBP_T_RD_CS] = {
 234                 .type = UE_CONTROL,
 235                 .endpoint = 0x00,       /* Control pipe */
 236                 .direction = UE_DIR_ANY,
 237                 .bufsize = sizeof(struct usb_device_request),
 238                 .callback = &udbp_bulk_read_clear_stall_callback,
 239                 .timeout = 1000,        /* 1 second */
 240                 .interval = 50, /* 50ms */
 241         },
 242 };
 243
 244 static devclass_t udbp_devclass;
 245
 246 static device_method_t udbp_methods[] = {
 247         /* Device interface */
 248         DEVMETHOD(device_probe, udbp_probe),
 249         DEVMETHOD(device_attach, udbp_attach),
 250         DEVMETHOD(device_detach, udbp_detach),
 251         {0, 0}
 252 };
 253
 254 static driver_t udbp_driver = {
 255         .name = "udbp",
 256         .methods = udbp_methods,
 257         .size = sizeof(struct udbp_softc),
 258 };
 259
 260 DRIVER_MODULE(udbp, uhub, udbp_driver, udbp_devclass, udbp_modload, 0);
 261 MODULE_DEPEND(udbp, netgraph, NG_ABI_VERSION, NG_ABI_VERSION, NG_ABI_VERSION);
 262 MODULE_DEPEND(udbp, usb, 1, 1, 1);
 263 MODULE_VERSION(udbp, 1);
 264
 265 static int
 266 udbp_modload(module_t mod, int event, void *data)
 267 {
 268         int error;
 269
 270         switch (event) {
 271         case MOD_LOAD:
 272                 error = ng_newtype(&ng_udbp_typestruct);
 273                 if (error != 0) {
 274                         printf("%s: Could not register "
 275                             "Netgraph node type, error=%d\n",
 276                             NG_UDBP_NODE_TYPE, error);
 277                 }
 278                 break;
 279
 280         case MOD_UNLOAD:
 281                 error = ng_rmtype(&ng_udbp_typestruct);
 282                 break;
 283
 284         default:
 285                 error = EOPNOTSUPP;
 286                 break;
 287         }
 288         return (error);
 289 }
 290
 291 static const STRUCT_USB_HOST_ID udbp_devs[] = {
 292         {USB_VPI(USB_VENDOR_NETCHIP, USB_PRODUCT_NETCHIP_TURBOCONNECT, 0)},
 293         {USB_VPI(USB_VENDOR_PROLIFIC, USB_PRODUCT_PROLIFIC_PL2301, 0)},
 294         {USB_VPI(USB_VENDOR_PROLIFIC, USB_PRODUCT_PROLIFIC_PL2302, 0)},
 295         {USB_VPI(USB_VENDOR_ANCHOR, USB_PRODUCT_ANCHOR_EZLINK, 0)},
 296         {USB_VPI(USB_VENDOR_GENESYS, USB_PRODUCT_GENESYS_GL620USB, 0)},
 297 };
 298
 299 static int
 300 udbp_probe(device_t dev)
 301 {
 302         struct usb_attach_arg *uaa = device_get_ivars(dev);
 303
 304         if (uaa->usb_mode != USB_MODE_HOST)
 305                 return (ENXIO);
 306         if (uaa->info.bConfigIndex != 0)
 307                 return (ENXIO);
 308         if (uaa->info.bIfaceIndex != 0)
 309                 return (ENXIO);
 310
 311         return (usbd_lookup_id_by_uaa(udbp_devs, sizeof(udbp_devs), uaa));
 312 }
 313
 314 static int
 315 udbp_attach(device_t dev)
 316 {
 317         struct usb_attach_arg *uaa = device_get_ivars(dev);
 318         struct udbp_softc *sc = device_get_softc(dev);
 319         int error;
 320
 321         device_set_usb_desc(dev);
 322
 323         snprintf(sc->sc_name, sizeof(sc->sc_name),
 324             "%s", device_get_nameunit(dev));
 325
 326         mtx_init(&sc->sc_mtx, "udbp lock", NULL, MTX_DEF | MTX_RECURSE);
 327
 328         error = usbd_transfer_setup(uaa->device, &uaa->info.bIfaceIndex,
 329             sc->sc_xfer, udbp_config, UDBP_T_MAX, sc, &sc->sc_mtx);
 330         if (error) {
 331                 DPRINTF("error=%s\n", usbd_errstr(error));
 332                 goto detach;
 333         }
 334         NG_BT_MBUFQ_INIT(&sc->sc_xmitq, UDBP_Q_MAXLEN);
 335
 336         NG_BT_MBUFQ_INIT(&sc->sc_xmitq_hipri, UDBP_Q_MAXLEN);
 337
 338         /* create Netgraph node */
 339
 340         if (ng_make_node_common(&ng_udbp_typestruct, &sc->sc_node) != 0) {
 341                 printf("%s: Could not create Netgraph node\n",
 342                     sc->sc_name);
 343                 sc->sc_node = NULL;
 344                 goto detach;
 345         }
 346         /* name node */
 347
 348         if (ng_name_node(sc->sc_node, sc->sc_name) != 0) {
 349                 printf("%s: Could not name node\n",
 350                     sc->sc_name);
 351                 NG_NODE_UNREF(sc->sc_node);
 352                 sc->sc_node = NULL;
 353                 goto detach;
 354         }
 355         NG_NODE_SET_PRIVATE(sc->sc_node, sc);
 356
 357         /* the device is now operational */
 358
 359         return (0);                     /* success */
 360
 361 detach:
 362         udbp_detach(dev);
 363         return (ENOMEM);                /* failure */
 364 }
 365
 366 static int
 367 udbp_detach(device_t dev)
 368 {
 369         struct udbp_softc *sc = device_get_softc(dev);
 370
 371         /* destroy Netgraph node */
 372
 373         if (sc->sc_node != NULL) {
 374                 NG_NODE_SET_PRIVATE(sc->sc_node, NULL);
 375                 ng_rmnode_self(sc->sc_node);
 376                 sc->sc_node = NULL;
 377         }
 378         /* free USB transfers, if any */
 379
 380         usbd_transfer_unsetup(sc->sc_xfer, UDBP_T_MAX);
 381
 382         mtx_destroy(&sc->sc_mtx);
 383
 384         /* destroy queues */
 385
 386         NG_BT_MBUFQ_DESTROY(&sc->sc_xmitq);
 387         NG_BT_MBUFQ_DESTROY(&sc->sc_xmitq_hipri);
 388
 389         /* extra check */
 390
 391         if (sc->sc_bulk_in_buffer) {
 392                 m_freem(sc->sc_bulk_in_buffer);
 393                 sc->sc_bulk_in_buffer = NULL;
 394         }
 395         return (0);                     /* success */
 396 }
 397
 398 static void
 399 udbp_bulk_read_callback(struct usb_xfer *xfer, usb_error_t error)
 400 {
 401         struct udbp_softc *sc = usbd_xfer_softc(xfer);
 402         struct usb_page_cache *pc;
 403         struct mbuf *m;
 404         int actlen;
 405
 406         usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);
 407
 408         switch (USB_GET_STATE(xfer)) {
 409         case USB_ST_TRANSFERRED:
 410
 411                 /* allocate new mbuf */
 412
 413                 MGETHDR(m, M_NOWAIT, MT_DATA);
 414
 415                 if (m == NULL) {
 416                         goto tr_setup;
 417                 }
 418                 MCLGET(m, M_NOWAIT);
 419
 420                 if (!(m->m_flags & M_EXT)) {
 421                         m_freem(m);
 422                         goto tr_setup;
 423                 }
 424                 m->m_pkthdr.len = m->m_len = actlen;
 425
 426                 pc = usbd_xfer_get_frame(xfer, 0);
 427                 usbd_copy_out(pc, 0, m->m_data, actlen);
 428
 429                 sc->sc_bulk_in_buffer = m;
 430
 431                 DPRINTF("received package %d bytes\n", actlen);
 432
 433         case USB_ST_SETUP:
 434 tr_setup:
 435                 if (sc->sc_bulk_in_buffer) {
 436                         ng_send_fn(sc->sc_node, NULL, &udbp_bulk_read_complete, NULL, 0);
 437                         return;
 438                 }
 439                 if (sc->sc_flags & UDBP_FLAG_READ_STALL) {
 440                         usbd_transfer_start(sc->sc_xfer[UDBP_T_RD_CS]);
 441                         return;
 442                 }
 443                 usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
 444                 usbd_transfer_submit(xfer);
 445                 return;
 446
 447         default:                        /* Error */
 448                 if (error != USB_ERR_CANCELLED) {
 449                         /* try to clear stall first */
 450                         sc->sc_flags |= UDBP_FLAG_READ_STALL;
 451                         usbd_transfer_start(sc->sc_xfer[UDBP_T_RD_CS]);
 452                 }
 453                 return;
 454
 455         }
 456 }
 457
 458 static void
 459 udbp_bulk_read_clear_stall_callback(struct usb_xfer *xfer, usb_error_t error)
 460 {
 461         struct udbp_softc *sc = usbd_xfer_softc(xfer);
 462         struct usb_xfer *xfer_other = sc->sc_xfer[UDBP_T_RD];
 463
 464         if (usbd_clear_stall_callback(xfer, xfer_other)) {
 465                 DPRINTF("stall cleared\n");
 466                 sc->sc_flags &= ~UDBP_FLAG_READ_STALL;
 467                 usbd_transfer_start(xfer_other);
 468         }
 469 }
 470
 471 static void
 472 udbp_bulk_read_complete(node_p node, hook_p hook, void *arg1, int arg2)
 473 {
 474         struct udbp_softc *sc = NG_NODE_PRIVATE(node);
 475         struct mbuf *m;
 476         int error;
 477
 478         if (sc == NULL) {
 479                 return;
 480         }
 481         mtx_lock(&sc->sc_mtx);
 482
 483         m = sc->sc_bulk_in_buffer;
 484
 485         if (m) {
 486
 487                 sc->sc_bulk_in_buffer = NULL;
 488
 489                 if ((sc->sc_hook == NULL) ||
 490                     NG_HOOK_NOT_VALID(sc->sc_hook)) {
 491                         DPRINTF("No upstream hook\n");
 492                         goto done;
 493                 }
 494                 sc->sc_packets_in++;
 495
 496                 NG_SEND_DATA_ONLY(error, sc->sc_hook, m);
 497
 498                 m = NULL;
 499         }
 500 done:
 501         if (m) {
 502                 m_freem(m);
 503         }
 504         /* start USB bulk-in transfer, if not already started */
 505
 506         usbd_transfer_start(sc->sc_xfer[UDBP_T_RD]);
 507
 508         mtx_unlock(&sc->sc_mtx);
 509 }
 510
 511 static void
 512 udbp_bulk_write_callback(struct usb_xfer *xfer, usb_error_t error)
 513 {
 514         struct udbp_softc *sc = usbd_xfer_softc(xfer);
 515         struct usb_page_cache *pc;
 516         struct mbuf *m;
 517
 518         switch (USB_GET_STATE(xfer)) {
 519         case USB_ST_TRANSFERRED:
 520
 521                 sc->sc_packets_out++;
 522
 523         case USB_ST_SETUP:
 524                 if (sc->sc_flags & UDBP_FLAG_WRITE_STALL) {
 525                         usbd_transfer_start(sc->sc_xfer[UDBP_T_WR_CS]);
 526                         return;
 527                 }
 528                 /* get next mbuf, if any */
 529
 530                 NG_BT_MBUFQ_DEQUEUE(&sc->sc_xmitq_hipri, m);
 531                 if (m == NULL) {
 532                         NG_BT_MBUFQ_DEQUEUE(&sc->sc_xmitq, m);
 533                         if (m == NULL) {
 534                                 DPRINTF("Data queue is empty\n");
 535                                 return;
 536                         }
 537                 }
 538                 if (m->m_pkthdr.len > MCLBYTES) {
 539                         DPRINTF("truncating large packet "
 540                             "from %d to %d bytes\n", m->m_pkthdr.len,
 541                             MCLBYTES);
 542                         m->m_pkthdr.len = MCLBYTES;
 543                 }
 544                 pc = usbd_xfer_get_frame(xfer, 0);
 545                 usbd_m_copy_in(pc, 0, m, 0, m->m_pkthdr.len);
 546
 547                 usbd_xfer_set_frame_len(xfer, 0, m->m_pkthdr.len);
 548
 549                 DPRINTF("packet out: %d bytes\n", m->m_pkthdr.len);
 550
 551                 m_freem(m);
 552
 553                 usbd_transfer_submit(xfer);
 554                 return;
 555
 556         default:                        /* Error */
 557                 if (error != USB_ERR_CANCELLED) {
 558                         /* try to clear stall first */
 559                         sc->sc_flags |= UDBP_FLAG_WRITE_STALL;
 560                         usbd_transfer_start(sc->sc_xfer[UDBP_T_WR_CS]);
 561                 }
 562                 return;
 563
 564         }
 565 }
 566
 567 static void
 568 udbp_bulk_write_clear_stall_callback(struct usb_xfer *xfer, usb_error_t error)
 569 {
 570         struct udbp_softc *sc = usbd_xfer_softc(xfer);
 571         struct usb_xfer *xfer_other = sc->sc_xfer[UDBP_T_WR];
 572
 573         if (usbd_clear_stall_callback(xfer, xfer_other)) {
 574                 DPRINTF("stall cleared\n");
 575                 sc->sc_flags &= ~UDBP_FLAG_WRITE_STALL;
 576                 usbd_transfer_start(xfer_other);
 577         }
 578 }
 579
 580 /***********************************************************************
 581  * Start of Netgraph methods
 582  **********************************************************************/
 583
 584 /*
 585  * If this is a device node so this work is done in the attach()
 586  * routine and the constructor will return EINVAL as you should not be able
 587  * to create nodes that depend on hardware (unless you can add the hardware :)
 588  */
 589 static int
 590 ng_udbp_constructor(node_p node)
 591 {
 592         return (EINVAL);
 593 }
 594
 595 /*
 596  * Give our ok for a hook to be added...
 597  * If we are not running this might kick a device into life.
 598  * Possibly decode information out of the hook name.
 599  * Add the hook's private info to the hook structure.
 600  * (if we had some). In this example, we assume that there is a
 601  * an array of structs, called 'channel' in the private info,
 602  * one for each active channel. The private
 603  * pointer of each hook points to the appropriate UDBP_hookinfo struct
 604  * so that the source of an input packet is easily identified.
 605  */
 606 static int
 607 ng_udbp_newhook(node_p node, hook_p hook, const char *name)
 608 {
 609         struct udbp_softc *sc = NG_NODE_PRIVATE(node);
 610         int32_t error = 0;
 611
 612         if (strcmp(name, NG_UDBP_HOOK_NAME)) {
 613                 return (EINVAL);
 614         }
 615         mtx_lock(&sc->sc_mtx);
 616
 617         if (sc->sc_hook != NULL) {
 618                 error = EISCONN;
 619         } else {
 620                 sc->sc_hook = hook;
 621                 NG_HOOK_SET_PRIVATE(hook, NULL);
 622         }
 623
 624         mtx_unlock(&sc->sc_mtx);
 625
 626         return (error);
 627 }
 628
 629 /*
 630  * Get a netgraph control message.
 631  * Check it is one we understand. If needed, send a response.
 632  * We could save the address for an async action later, but don't here.
 633  * Always free the message.
 634  * The response should be in a malloc'd region that the caller can 'free'.
 635  * A response is not required.
 636  * Theoretically you could respond defferently to old message types if
 637  * the cookie in the header didn't match what we consider to be current
 638  * (so that old userland programs could continue to work).
 639  */
 640 static int
 641 ng_udbp_rcvmsg(node_p node, item_p item, hook_p lasthook)
 642 {
 643         struct udbp_softc *sc = NG_NODE_PRIVATE(node);
 644         struct ng_mesg *resp = NULL;
 645         int error = 0;
 646         struct ng_mesg *msg;
 647
 648         NGI_GET_MSG(item, msg);
 649         /* Deal with message according to cookie and command */
 650         switch (msg->header.typecookie) {
 651         case NGM_UDBP_COOKIE:
 652                 switch (msg->header.cmd) {
 653                 case NGM_UDBP_GET_STATUS:
 654                         {
 655                                 struct ngudbpstat *stats;
 656
 657                                 NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
 658                                 if (!resp) {
 659                                         error = ENOMEM;
 660                                         break;
 661                                 }
 662                                 stats = (struct ngudbpstat *)resp->data;
 663                                 mtx_lock(&sc->sc_mtx);
 664                                 stats->packets_in = sc->sc_packets_in;
 665                                 stats->packets_out = sc->sc_packets_out;
 666                                 mtx_unlock(&sc->sc_mtx);
 667                                 break;
 668                         }
 669                 case NGM_UDBP_SET_FLAG:
 670                         if (msg->header.arglen != sizeof(uint32_t)) {
 671                                 error = EINVAL;
 672                                 break;
 673                         }
 674                         DPRINTF("flags = 0x%08x\n",
 675                             *((uint32_t *)msg->data));
 676                         break;
 677                 default:
 678                         error = EINVAL; /* unknown command */
 679                         break;
 680                 }
 681                 break;
 682         default:
 683                 error = EINVAL;         /* unknown cookie type */
 684                 break;
 685         }
 686
 687         /* Take care of synchronous response, if any */
 688         NG_RESPOND_MSG(error, node, item, resp);
 689         NG_FREE_MSG(msg);
 690         return (error);
 691 }
 692
 693 /*
 694  * Accept data from the hook and queue it for output.
 695  */
 696 static int
 697 ng_udbp_rcvdata(hook_p hook, item_p item)
 698 {
 699         struct udbp_softc *sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 700         struct ng_bt_mbufq *queue_ptr;
 701         struct mbuf *m;
 702         struct ng_tag_prio *ptag;
 703         int error;
 704
 705         if (sc == NULL) {
 706                 NG_FREE_ITEM(item);
 707                 return (EHOSTDOWN);
 708         }
 709         NGI_GET_M(item, m);
 710         NG_FREE_ITEM(item);
 711
 712         /*
 713          * Now queue the data for when it can be sent
 714          */
 715         ptag = (void *)m_tag_locate(m, NGM_GENERIC_COOKIE,
 716             NG_TAG_PRIO, NULL);
 717
 718         if (ptag && (ptag->priority > NG_PRIO_CUTOFF))
 719                 queue_ptr = &sc->sc_xmitq_hipri;
 720         else
 721                 queue_ptr = &sc->sc_xmitq;
 722
 723         mtx_lock(&sc->sc_mtx);
 724
 725         if (NG_BT_MBUFQ_FULL(queue_ptr)) {
 726                 NG_BT_MBUFQ_DROP(queue_ptr);
 727                 NG_FREE_M(m);
 728                 error = ENOBUFS;
 729         } else {
 730                 NG_BT_MBUFQ_ENQUEUE(queue_ptr, m);
 731                 /*
 732                  * start bulk-out transfer, if not already started:
 733                  */
 734                 usbd_transfer_start(sc->sc_xfer[UDBP_T_WR]);
 735                 error = 0;
 736         }
 737
 738         mtx_unlock(&sc->sc_mtx);
 739
 740         return (error);
 741 }
 742
 743 /*
 744  * Do local shutdown processing..
 745  * We are a persistant device, we refuse to go away, and
 746  * only remove our links and reset ourself.
 747  */
 748 static int
 749 ng_udbp_rmnode(node_p node)
 750 {
 751         struct udbp_softc *sc = NG_NODE_PRIVATE(node);
 752
 753         /* Let old node go */
 754         NG_NODE_SET_PRIVATE(node, NULL);
 755         NG_NODE_UNREF(node);            /* forget it ever existed */
 756
 757         if (sc == NULL) {
 758                 goto done;
 759         }
 760         /* Create Netgraph node */
 761         if (ng_make_node_common(&ng_udbp_typestruct, &sc->sc_node) != 0) {
 762                 printf("%s: Could not create Netgraph node\n",
 763                     sc->sc_name);
 764                 sc->sc_node = NULL;
 765                 goto done;
 766         }
 767         /* Name node */
 768         if (ng_name_node(sc->sc_node, sc->sc_name) != 0) {
 769                 printf("%s: Could not name Netgraph node\n",
 770                     sc->sc_name);
 771                 NG_NODE_UNREF(sc->sc_node);
 772                 sc->sc_node = NULL;
 773                 goto done;
 774         }
 775         NG_NODE_SET_PRIVATE(sc->sc_node, sc);
 776
 777 done:
 778         if (sc) {
 779                 mtx_unlock(&sc->sc_mtx);
 780         }
 781         return (0);
 782 }
 783
 784 /*
 785  * This is called once we've already connected a new hook to the other node.
 786  * It gives us a chance to balk at the last minute.
 787  */
 788 static int
 789 ng_udbp_connect(hook_p hook)
 790 {
 791         struct udbp_softc *sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 792
 793         /* probably not at splnet, force outward queueing */
 794         NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook));
 795
 796         mtx_lock(&sc->sc_mtx);
 797
 798         sc->sc_flags |= (UDBP_FLAG_READ_STALL |
 799             UDBP_FLAG_WRITE_STALL);
 800
 801         /* start bulk-in transfer */
 802         usbd_transfer_start(sc->sc_xfer[UDBP_T_RD]);
 803
 804         /* start bulk-out transfer */
 805         usbd_transfer_start(sc->sc_xfer[UDBP_T_WR]);
 806
 807         mtx_unlock(&sc->sc_mtx);
 808
 809         return (0);
 810 }
 811
 812 /*
 813  * Dook disconnection
 814  *
 815  * For this type, removal of the last link destroys the node
 816  */
 817 static int
 818 ng_udbp_disconnect(hook_p hook)
 819 {
 820         struct udbp_softc *sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 821         int error = 0;
 822
 823         if (sc != NULL) {
 824
 825                 mtx_lock(&sc->sc_mtx);
 826
 827                 if (hook != sc->sc_hook) {
 828                         error = EINVAL;
 829                 } else {
 830
 831                         /* stop bulk-in transfer */
 832                         usbd_transfer_stop(sc->sc_xfer[UDBP_T_RD_CS]);
 833                         usbd_transfer_stop(sc->sc_xfer[UDBP_T_RD]);
 834
 835                         /* stop bulk-out transfer */
 836                         usbd_transfer_stop(sc->sc_xfer[UDBP_T_WR_CS]);
 837                         usbd_transfer_stop(sc->sc_xfer[UDBP_T_WR]);
 838
 839                         /* cleanup queues */
 840                         NG_BT_MBUFQ_DRAIN(&sc->sc_xmitq);
 841                         NG_BT_MBUFQ_DRAIN(&sc->sc_xmitq_hipri);
 842
 843                         if (sc->sc_bulk_in_buffer) {
 844                                 m_freem(sc->sc_bulk_in_buffer);
 845                                 sc->sc_bulk_in_buffer = NULL;
 846                         }
 847                         sc->sc_hook = NULL;
 848                 }
 849
 850                 mtx_unlock(&sc->sc_mtx);
 851         }
 852         if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
 853             && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
 854                 ng_rmnode_self(NG_HOOK_NODE(hook));
 855
 856         return (error);
 857 }