drivers/staging/usbip/vhci_hcd.c

   1 /*
   2  * Copyright (C) 2003-2008 Takahiro Hirofuchi
   3  *
   4  * This is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  17  * USA.
  18  */
  19
  20 #include <linux/init.h>
  21 #include <linux/kernel.h>
  22 #include <linux/kthread.h>
  23 #include <linux/module.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/slab.h>
  26
  27 #include "usbip_common.h"
  28 #include "vhci.h"
  29
  30 #define DRIVER_AUTHOR "Takahiro Hirofuchi"
  31 #define DRIVER_DESC "USB/IP 'Virtual' Host Controller (VHCI) Driver"
  32
  33 /*
  34  * TODO
  35  *      - update root hub emulation
  36  *      - move the emulation code to userland ?
  37  *              porting to other operating systems
  38  *              minimize kernel code
  39  *      - add suspend/resume code
  40  *      - clean up everything
  41  */
  42
  43 /* See usb gadget dummy hcd */
  44
  45 static int vhci_hub_status(struct usb_hcd *hcd, char *buff);
  46 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
  47                             u16 wIndex, char *buff, u16 wLength);
  48 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
  49                             gfp_t mem_flags);
  50 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status);
  51 static int vhci_start(struct usb_hcd *vhci_hcd);
  52 static void vhci_stop(struct usb_hcd *hcd);
  53 static int vhci_get_frame_number(struct usb_hcd *hcd);
  54
  55 static const char driver_name[] = "vhci_hcd";
  56 static const char driver_desc[] = "USB/IP Virtual Host Controller";
  57
  58 struct vhci_hcd *the_controller;
  59
  60 static const char * const bit_desc[] = {
  61         "CONNECTION",           /*0*/
  62         "ENABLE",               /*1*/
  63         "SUSPEND",              /*2*/
  64         "OVER_CURRENT",         /*3*/
  65         "RESET",                /*4*/
  66         "R5",                   /*5*/
  67         "R6",                   /*6*/
  68         "R7",                   /*7*/
  69         "POWER",                /*8*/
  70         "LOWSPEED",             /*9*/
  71         "HIGHSPEED",            /*10*/
  72         "PORT_TEST",            /*11*/
  73         "INDICATOR",            /*12*/
  74         "R13",                  /*13*/
  75         "R14",                  /*14*/
  76         "R15",                  /*15*/
  77         "C_CONNECTION",         /*16*/
  78         "C_ENABLE",             /*17*/
  79         "C_SUSPEND",            /*18*/
  80         "C_OVER_CURRENT",       /*19*/
  81         "C_RESET",              /*20*/
  82         "R21",                  /*21*/
  83         "R22",                  /*22*/
  84         "R23",                  /*23*/
  85         "R24",                  /*24*/
  86         "R25",                  /*25*/
  87         "R26",                  /*26*/
  88         "R27",                  /*27*/
  89         "R28",                  /*28*/
  90         "R29",                  /*29*/
  91         "R30",                  /*30*/
  92         "R31",                  /*31*/
  93 };
  94
  95 static void dump_port_status(u32 status)
  96 {
  97         int i = 0;
  98
  99         pr_debug("status %08x:", status);
 100         for (i = 0; i < 32; i++) {
 101                 if (status & (1 << i))
 102                         pr_debug(" %s", bit_desc[i]);
 103         }
 104         pr_debug("\n");
 105 }
 106
 107 void rh_port_connect(int rhport, enum usb_device_speed speed)
 108 {
 109         unsigned long   flags;
 110
 111         usbip_dbg_vhci_rh("rh_port_connect %d\n", rhport);
 112
 113         spin_lock_irqsave(&the_controller->lock, flags);
 114
 115         the_controller->port_status[rhport] |= USB_PORT_STAT_CONNECTION
 116                 | (1 << USB_PORT_FEAT_C_CONNECTION);
 117
 118         switch (speed) {
 119         case USB_SPEED_HIGH:
 120                 the_controller->port_status[rhport] |= USB_PORT_STAT_HIGH_SPEED;
 121                 break;
 122         case USB_SPEED_LOW:
 123                 the_controller->port_status[rhport] |= USB_PORT_STAT_LOW_SPEED;
 124                 break;
 125         default:
 126                 break;
 127         }
 128
 129         /* spin_lock(&the_controller->vdev[rhport].ud.lock);
 130          * the_controller->vdev[rhport].ud.status = VDEV_CONNECT;
 131          * spin_unlock(&the_controller->vdev[rhport].ud.lock); */
 132
 133         spin_unlock_irqrestore(&the_controller->lock, flags);
 134
 135         usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 136 }
 137
 138 void rh_port_disconnect(int rhport)
 139 {
 140         unsigned long flags;
 141
 142         usbip_dbg_vhci_rh("rh_port_disconnect %d\n", rhport);
 143
 144         spin_lock_irqsave(&the_controller->lock, flags);
 145         /* stop_activity(dum, driver); */
 146         the_controller->port_status[rhport] &= ~USB_PORT_STAT_CONNECTION;
 147         the_controller->port_status[rhport] |=
 148                                         (1 << USB_PORT_FEAT_C_CONNECTION);
 149
 150         /* not yet complete the disconnection
 151          * spin_lock(&vdev->ud.lock);
 152          * vdev->ud.status = VHC_ST_DISCONNECT;
 153          * spin_unlock(&vdev->ud.lock); */
 154
 155         spin_unlock_irqrestore(&the_controller->lock, flags);
 156         usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 157 }
 158
 159 #define PORT_C_MASK                             \
 160         ((USB_PORT_STAT_C_CONNECTION            \
 161           | USB_PORT_STAT_C_ENABLE              \
 162           | USB_PORT_STAT_C_SUSPEND             \
 163           | USB_PORT_STAT_C_OVERCURRENT         \
 164           | USB_PORT_STAT_C_RESET) << 16)
 165
 166 /*
 167  * This function is almostly the same as dummy_hcd.c:dummy_hub_status() without
 168  * suspend/resume support. But, it is modified to provide multiple ports.
 169  *
 170  * @buf: a bitmap to show which port status has been changed.
 171  *  bit  0: reserved or used for another purpose?
 172  *  bit  1: the status of port 0 has been changed.
 173  *  bit  2: the status of port 1 has been changed.
 174  *  ...
 175  *  bit  7: the status of port 6 has been changed.
 176  *  bit  8: the status of port 7 has been changed.
 177  *  ...
 178  *  bit 15: the status of port 14 has been changed.
 179  *
 180  * So, the maximum number of ports is 31 ( port 0 to port 30) ?
 181  *
 182  * The return value is the actual transferred length in byte. If nothing has
 183  * been changed, return 0. In the case that the number of ports is less than or
 184  * equal to 6 (VHCI_NPORTS==7), return 1.
 185  *
 186  */
 187 static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
 188 {
 189         struct vhci_hcd *vhci;
 190         unsigned long   flags;
 191         int             retval = 0;
 192
 193         /* the enough buffer is allocated according to USB_MAXCHILDREN */
 194         unsigned long   *event_bits = (unsigned long *) buf;
 195         int             rhport;
 196         int             changed = 0;
 197
 198         *event_bits = 0;
 199
 200         vhci = hcd_to_vhci(hcd);
 201
 202         spin_lock_irqsave(&vhci->lock, flags);
 203         if (!HCD_HW_ACCESSIBLE(hcd)) {
 204                 usbip_dbg_vhci_rh("hw accessible flag in on?\n");
 205                 goto done;
 206         }
 207
 208         /* check pseudo status register for each port */
 209         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 210                 if ((vhci->port_status[rhport] & PORT_C_MASK)) {
 211                         /* The status of a port has been changed, */
 212                         usbip_dbg_vhci_rh("port %d is changed\n", rhport);
 213
 214                         *event_bits |= 1 << (rhport + 1);
 215                         changed = 1;
 216                 }
 217         }
 218
 219         pr_info("changed %d\n", changed);
 220
 221         if (hcd->state == HC_STATE_SUSPENDED)
 222                 usb_hcd_resume_root_hub(hcd);
 223
 224         if (changed)
 225                 retval = 1 + (VHCI_NPORTS / 8);
 226         else
 227                 retval = 0;
 228
 229 done:
 230         spin_unlock_irqrestore(&vhci->lock, flags);
 231         return retval;
 232 }
 233
 234 /* See hub_configure in hub.c */
 235 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
 236 {
 237         memset(desc, 0, sizeof(*desc));
 238         desc->bDescriptorType = 0x29;
 239         desc->bDescLength = 9;
 240         desc->wHubCharacteristics = (__force __u16)
 241                 (__constant_cpu_to_le16(0x0001));
 242         desc->bNbrPorts = VHCI_NPORTS;
 243         desc->u.hs.DeviceRemovable[0] = 0xff;
 244         desc->u.hs.DeviceRemovable[1] = 0xff;
 245 }
 246
 247 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 248                             u16 wIndex, char *buf, u16 wLength)
 249 {
 250         struct vhci_hcd *dum;
 251         int             retval = 0;
 252         unsigned long   flags;
 253         int             rhport;
 254
 255         u32 prev_port_status[VHCI_NPORTS];
 256
 257         if (!HCD_HW_ACCESSIBLE(hcd))
 258                 return -ETIMEDOUT;
 259
 260         /*
 261          * NOTE:
 262          * wIndex shows the port number and begins from 1.
 263          */
 264         usbip_dbg_vhci_rh("typeReq %x wValue %x wIndex %x\n", typeReq, wValue,
 265                           wIndex);
 266         if (wIndex > VHCI_NPORTS)
 267                 pr_err("invalid port number %d\n", wIndex);
 268         rhport = ((__u8)(wIndex & 0x00ff)) - 1;
 269
 270         dum = hcd_to_vhci(hcd);
 271
 272         spin_lock_irqsave(&dum->lock, flags);
 273
 274         /* store old status and compare now and old later */
 275         if (usbip_dbg_flag_vhci_rh) {
 276                 int i = 0;
 277                 for (i = 0; i < VHCI_NPORTS; i++)
 278                         prev_port_status[i] = dum->port_status[i];
 279         }
 280
 281         switch (typeReq) {
 282         case ClearHubFeature:
 283                 usbip_dbg_vhci_rh(" ClearHubFeature\n");
 284                 break;
 285         case ClearPortFeature:
 286                 switch (wValue) {
 287                 case USB_PORT_FEAT_SUSPEND:
 288                         if (dum->port_status[rhport] & USB_PORT_STAT_SUSPEND) {
 289                                 /* 20msec signaling */
 290                                 dum->resuming = 1;
 291                                 dum->re_timeout =
 292                                         jiffies + msecs_to_jiffies(20);
 293                         }
 294                         break;
 295                 case USB_PORT_FEAT_POWER:
 296                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 297                                           "USB_PORT_FEAT_POWER\n");
 298                         dum->port_status[rhport] = 0;
 299                         /* dum->address = 0; */
 300                         /* dum->hdev = 0; */
 301                         dum->resuming = 0;
 302                         break;
 303                 case USB_PORT_FEAT_C_RESET:
 304                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 305                                           "USB_PORT_FEAT_C_RESET\n");
 306                         switch (dum->vdev[rhport].speed) {
 307                         case USB_SPEED_HIGH:
 308                                 dum->port_status[rhport] |=
 309                                         USB_PORT_STAT_HIGH_SPEED;
 310                                 break;
 311                         case USB_SPEED_LOW:
 312                                 dum->port_status[rhport] |=
 313                                         USB_PORT_STAT_LOW_SPEED;
 314                                 break;
 315                         default:
 316                                 break;
 317                         }
 318                 default:
 319                         usbip_dbg_vhci_rh(" ClearPortFeature: default %x\n",
 320                                           wValue);
 321                         dum->port_status[rhport] &= ~(1 << wValue);
 322                         break;
 323                 }
 324                 break;
 325         case GetHubDescriptor:
 326                 usbip_dbg_vhci_rh(" GetHubDescriptor\n");
 327                 hub_descriptor((struct usb_hub_descriptor *) buf);
 328                 break;
 329         case GetHubStatus:
 330                 usbip_dbg_vhci_rh(" GetHubStatus\n");
 331                 *(__le32 *) buf = __constant_cpu_to_le32(0);
 332                 break;
 333         case GetPortStatus:
 334                 usbip_dbg_vhci_rh(" GetPortStatus port %x\n", wIndex);
 335                 if (wIndex > VHCI_NPORTS || wIndex < 1) {
 336                         pr_err("invalid port number %d\n", wIndex);
 337                         retval = -EPIPE;
 338                 }
 339
 340                 /* we do no care of resume. */
 341
 342                 /* whoever resets or resumes must GetPortStatus to
 343                  * complete it!!
 344                  *                                   */
 345                 if (dum->resuming && time_after(jiffies, dum->re_timeout)) {
 346                         dum->port_status[rhport] |=
 347                                         (1 << USB_PORT_FEAT_C_SUSPEND);
 348                         dum->port_status[rhport] &=
 349                                         ~(1 << USB_PORT_FEAT_SUSPEND);
 350                         dum->resuming = 0;
 351                         dum->re_timeout = 0;
 352                         /* if (dum->driver && dum->driver->resume) {
 353                          *      spin_unlock (&dum->lock);
 354                          *      dum->driver->resume (&dum->gadget);
 355                          *      spin_lock (&dum->lock);
 356                          * } */
 357                 }
 358
 359                 if ((dum->port_status[rhport] & (1 << USB_PORT_FEAT_RESET)) !=
 360                     0 && time_after(jiffies, dum->re_timeout)) {
 361                         dum->port_status[rhport] |=
 362                                 (1 << USB_PORT_FEAT_C_RESET);
 363                         dum->port_status[rhport] &=
 364                                 ~(1 << USB_PORT_FEAT_RESET);
 365                         dum->re_timeout = 0;
 366
 367                         if (dum->vdev[rhport].ud.status ==
 368                             VDEV_ST_NOTASSIGNED) {
 369                                 usbip_dbg_vhci_rh(" enable rhport %d "
 370                                                   "(status %u)\n",
 371                                                   rhport,
 372                                                   dum->vdev[rhport].ud.status);
 373                                 dum->port_status[rhport] |=
 374                                         USB_PORT_STAT_ENABLE;
 375                         }
 376 #if 0
 377                         if (dum->driver) {
 378                                 dum->port_status[rhport] |=
 379                                         USB_PORT_STAT_ENABLE;
 380                                 /* give it the best speed we agree on */
 381                                 dum->gadget.speed = dum->driver->speed;
 382                                 dum->gadget.ep0->maxpacket = 64;
 383                                 switch (dum->gadget.speed) {
 384                                 case USB_SPEED_HIGH:
 385                                         dum->port_status[rhport] |=
 386                                                 USB_PORT_STAT_HIGH_SPEED;
 387                                         break;
 388                                 case USB_SPEED_LOW:
 389                                         dum->gadget.ep0->maxpacket = 8;
 390                                         dum->port_status[rhport] |=
 391                                                 USB_PORT_STAT_LOW_SPEED;
 392                                         break;
 393                                 default:
 394                                         dum->gadget.speed = USB_SPEED_FULL;
 395                                         break;
 396                                 }
 397                         }
 398 #endif
 399                 }
 400                 ((u16 *) buf)[0] = cpu_to_le16(dum->port_status[rhport]);
 401                 ((u16 *) buf)[1] = cpu_to_le16(dum->port_status[rhport] >> 16);
 402
 403                 usbip_dbg_vhci_rh(" GetPortStatus bye %x %x\n", ((u16 *)buf)[0],
 404                                   ((u16 *)buf)[1]);
 405                 break;
 406         case SetHubFeature:
 407                 usbip_dbg_vhci_rh(" SetHubFeature\n");
 408                 retval = -EPIPE;
 409                 break;
 410         case SetPortFeature:
 411                 switch (wValue) {
 412                 case USB_PORT_FEAT_SUSPEND:
 413                         usbip_dbg_vhci_rh(" SetPortFeature: "
 414                                           "USB_PORT_FEAT_SUSPEND\n");
 415 #if 0
 416                         dum->port_status[rhport] |=
 417                                 (1 << USB_PORT_FEAT_SUSPEND);
 418                         if (dum->driver->suspend) {
 419                                 spin_unlock(&dum->lock);
 420                                 dum->driver->suspend(&dum->gadget);
 421                                 spin_lock(&dum->lock);
 422                         }
 423 #endif
 424                         break;
 425                 case USB_PORT_FEAT_RESET:
 426                         usbip_dbg_vhci_rh(" SetPortFeature: "
 427                                           "USB_PORT_FEAT_RESET\n");
 428                         /* if it's already running, disconnect first */
 429                         if (dum->port_status[rhport] & USB_PORT_STAT_ENABLE) {
 430                                 dum->port_status[rhport] &=
 431                                         ~(USB_PORT_STAT_ENABLE |
 432                                           USB_PORT_STAT_LOW_SPEED |
 433                                           USB_PORT_STAT_HIGH_SPEED);
 434 #if 0
 435                                 if (dum->driver) {
 436                                         dev_dbg(hardware, "disconnect\n");
 437                                         stop_activity(dum, dum->driver);
 438                                 }
 439 #endif
 440
 441                                 /* FIXME test that code path! */
 442                         }
 443                         /* 50msec reset signaling */
 444                         dum->re_timeout = jiffies + msecs_to_jiffies(50);
 445
 446                         /* FALLTHROUGH */
 447                 default:
 448                         usbip_dbg_vhci_rh(" SetPortFeature: default %d\n",
 449                                           wValue);
 450                         dum->port_status[rhport] |= (1 << wValue);
 451                         break;
 452                 }
 453                 break;
 454
 455         default:
 456                 pr_err("default: no such request\n");
 457                 /* dev_dbg (hardware,
 458                  *              "hub control req%04x v%04x i%04x l%d\n",
 459                  *              typeReq, wValue, wIndex, wLength); */
 460
 461                 /* "protocol stall" on error */
 462                 retval = -EPIPE;
 463         }
 464
 465         if (usbip_dbg_flag_vhci_rh) {
 466                 pr_debug("port %d\n", rhport);
 467                 dump_port_status(prev_port_status[rhport]);
 468                 dump_port_status(dum->port_status[rhport]);
 469         }
 470         usbip_dbg_vhci_rh(" bye\n");
 471
 472         spin_unlock_irqrestore(&dum->lock, flags);
 473
 474         return retval;
 475 }
 476
 477 static struct vhci_device *get_vdev(struct usb_device *udev)
 478 {
 479         int i;
 480
 481         if (!udev)
 482                 return NULL;
 483
 484         for (i = 0; i < VHCI_NPORTS; i++)
 485                 if (the_controller->vdev[i].udev == udev)
 486                         return port_to_vdev(i);
 487
 488         return NULL;
 489 }
 490
 491 static void vhci_tx_urb(struct urb *urb)
 492 {
 493         struct vhci_device *vdev = get_vdev(urb->dev);
 494         struct vhci_priv *priv;
 495         unsigned long flag;
 496
 497         if (!vdev) {
 498                 pr_err("could not get virtual device");
 499                 /* BUG(); */
 500                 return;
 501         }
 502
 503         priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
 504
 505         spin_lock_irqsave(&vdev->priv_lock, flag);
 506
 507         if (!priv) {
 508                 dev_err(&urb->dev->dev, "malloc vhci_priv\n");
 509                 spin_unlock_irqrestore(&vdev->priv_lock, flag);
 510                 usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 511                 return;
 512         }
 513
 514         priv->seqnum = atomic_inc_return(&the_controller->seqnum);
 515         if (priv->seqnum == 0xffff)
 516                 dev_info(&urb->dev->dev, "seqnum max\n");
 517
 518         priv->vdev = vdev;
 519         priv->urb = urb;
 520
 521         urb->hcpriv = (void *) priv;
 522
 523         list_add_tail(&priv->list, &vdev->priv_tx);
 524
 525         wake_up(&vdev->waitq_tx);
 526         spin_unlock_irqrestore(&vdev->priv_lock, flag);
 527 }
 528
 529 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 530                             gfp_t mem_flags)
 531 {
 532         struct device *dev = &urb->dev->dev;
 533         int ret = 0;
 534         unsigned long flags;
 535         struct vhci_device *vdev;
 536
 537         usbip_dbg_vhci_hc("enter, usb_hcd %p urb %p mem_flags %d\n",
 538                           hcd, urb, mem_flags);
 539
 540         /* patch to usb_sg_init() is in 2.5.60 */
 541         BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);
 542
 543         spin_lock_irqsave(&the_controller->lock, flags);
 544
 545         if (urb->status != -EINPROGRESS) {
 546                 dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
 547                 spin_unlock_irqrestore(&the_controller->lock, flags);
 548                 return urb->status;
 549         }
 550
 551         vdev = port_to_vdev(urb->dev->portnum-1);
 552
 553         /* refuse enqueue for dead connection */
 554         spin_lock(&vdev->ud.lock);
 555         if (vdev->ud.status == VDEV_ST_NULL ||
 556             vdev->ud.status == VDEV_ST_ERROR) {
 557                 dev_err(dev, "enqueue for inactive port %d\n", vdev->rhport);
 558                 spin_unlock(&vdev->ud.lock);
 559                 spin_unlock_irqrestore(&the_controller->lock, flags);
 560                 return -ENODEV;
 561         }
 562         spin_unlock(&vdev->ud.lock);
 563
 564         ret = usb_hcd_link_urb_to_ep(hcd, urb);
 565         if (ret)
 566                 goto no_need_unlink;
 567
 568         /*
 569          * The enumeration process is as follows;
 570          *
 571          *  1. Get_Descriptor request to DevAddrs(0) EndPoint(0)
 572          *     to get max packet length of default pipe
 573          *
 574          *  2. Set_Address request to DevAddr(0) EndPoint(0)
 575          *
 576          */
 577         if (usb_pipedevice(urb->pipe) == 0) {
 578                 __u8 type = usb_pipetype(urb->pipe);
 579                 struct usb_ctrlrequest *ctrlreq =
 580                         (struct usb_ctrlrequest *) urb->setup_packet;
 581
 582                 if (type != PIPE_CONTROL || !ctrlreq) {
 583                         dev_err(dev, "invalid request to devnum 0\n");
 584                         ret = -EINVAL;
 585                         goto no_need_xmit;
 586                 }
 587
 588                 switch (ctrlreq->bRequest) {
 589                 case USB_REQ_SET_ADDRESS:
 590                         /* set_address may come when a device is reset */
 591                         dev_info(dev, "SetAddress Request (%d) to port %d\n",
 592                                  ctrlreq->wValue, vdev->rhport);
 593
 594                         if (vdev->udev)
 595                                 usb_put_dev(vdev->udev);
 596                         vdev->udev = usb_get_dev(urb->dev);
 597
 598                         spin_lock(&vdev->ud.lock);
 599                         vdev->ud.status = VDEV_ST_USED;
 600                         spin_unlock(&vdev->ud.lock);
 601
 602                         if (urb->status == -EINPROGRESS) {
 603                                 /* This request is successfully completed. */
 604                                 /* If not -EINPROGRESS, possibly unlinked. */
 605                                 urb->status = 0;
 606                         }
 607
 608                         goto no_need_xmit;
 609
 610                 case USB_REQ_GET_DESCRIPTOR:
 611                         if (ctrlreq->wValue == (USB_DT_DEVICE << 8))
 612                                 usbip_dbg_vhci_hc("Not yet?: "
 613                                                   "Get_Descriptor to device 0 "
 614                                                   "(get max pipe size)\n");
 615
 616                         if (vdev->udev)
 617                                 usb_put_dev(vdev->udev);
 618                         vdev->udev = usb_get_dev(urb->dev);
 619                         goto out;
 620
 621                 default:
 622                         /* NOT REACHED */
 623                         dev_err(dev, "invalid request to devnum 0 bRequest %u, "
 624                                 "wValue %u\n", ctrlreq->bRequest,
 625                                 ctrlreq->wValue);
 626                         ret =  -EINVAL;
 627                         goto no_need_xmit;
 628                 }
 629
 630         }
 631
 632 out:
 633         vhci_tx_urb(urb);
 634         spin_unlock_irqrestore(&the_controller->lock, flags);
 635
 636         return 0;
 637
 638 no_need_xmit:
 639         usb_hcd_unlink_urb_from_ep(hcd, urb);
 640 no_need_unlink:
 641         spin_unlock_irqrestore(&the_controller->lock, flags);
 642
 643         usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
 644
 645         return ret;
 646 }
 647
 648 /*
 649  * vhci_rx gives back the urb after receiving the reply of the urb.  If an
 650  * unlink pdu is sent or not, vhci_rx receives a normal return pdu and gives
 651  * back its urb. For the driver unlinking the urb, the content of the urb is
 652  * not important, but the calling to its completion handler is important; the
 653  * completion of unlinking is notified by the completion handler.
 654  *
 655  *
 656  * CLIENT SIDE
 657  *
 658  * - When vhci_hcd receives RET_SUBMIT,
 659  *
 660  *      - case 1a). the urb of the pdu is not unlinking.
 661  *              - normal case
 662  *              => just give back the urb
 663  *
 664  *      - case 1b). the urb of the pdu is unlinking.
 665  *              - usbip.ko will return a reply of the unlinking request.
 666  *              => give back the urb now and go to case 2b).
 667  *
 668  * - When vhci_hcd receives RET_UNLINK,
 669  *
 670  *      - case 2a). a submit request is still pending in vhci_hcd.
 671  *              - urb was really pending in usbip.ko and urb_unlink_urb() was
 672  *                completed there.
 673  *              => free a pending submit request
 674  *              => notify unlink completeness by giving back the urb
 675  *
 676  *      - case 2b). a submit request is *not* pending in vhci_hcd.
 677  *              - urb was already given back to the core driver.
 678  *              => do not give back the urb
 679  *
 680  *
 681  * SERVER SIDE
 682  *
 683  * - When usbip receives CMD_UNLINK,
 684  *
 685  *      - case 3a). the urb of the unlink request is now in submission.
 686  *              => do usb_unlink_urb().
 687  *              => after the unlink is completed, send RET_UNLINK.
 688  *
 689  *      - case 3b). the urb of the unlink request is not in submission.
 690  *              - may be already completed or never be received
 691  *              => send RET_UNLINK
 692  *
 693  */
 694 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 695 {
 696         unsigned long flags;
 697         struct vhci_priv *priv;
 698         struct vhci_device *vdev;
 699
 700         pr_info("dequeue a urb %p\n", urb);
 701
 702         spin_lock_irqsave(&the_controller->lock, flags);
 703
 704         priv = urb->hcpriv;
 705         if (!priv) {
 706                 /* URB was never linked! or will be soon given back by
 707                  * vhci_rx. */
 708                 spin_unlock_irqrestore(&the_controller->lock, flags);
 709                 return 0;
 710         }
 711
 712         {
 713                 int ret = 0;
 714                 ret = usb_hcd_check_unlink_urb(hcd, urb, status);
 715                 if (ret) {
 716                         spin_unlock_irqrestore(&the_controller->lock, flags);
 717                         return ret;
 718                 }
 719         }
 720
 721          /* send unlink request here? */
 722         vdev = priv->vdev;
 723
 724         if (!vdev->ud.tcp_socket) {
 725                 /* tcp connection is closed */
 726                 unsigned long flags2;
 727
 728                 spin_lock_irqsave(&vdev->priv_lock, flags2);
 729
 730                 pr_info("device %p seems to be disconnected\n", vdev);
 731                 list_del(&priv->list);
 732                 kfree(priv);
 733                 urb->hcpriv = NULL;
 734
 735                 spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 736
 737                 /*
 738                  * If tcp connection is alive, we have sent CMD_UNLINK.
 739                  * vhci_rx will receive RET_UNLINK and give back the URB.
 740                  * Otherwise, we give back it here.
 741                  */
 742                 pr_info("gives back urb %p\n", urb);
 743
 744                 usb_hcd_unlink_urb_from_ep(hcd, urb);
 745
 746                 spin_unlock_irqrestore(&the_controller->lock, flags);
 747                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 748                                      urb->status);
 749                 spin_lock_irqsave(&the_controller->lock, flags);
 750
 751         } else {
 752                 /* tcp connection is alive */
 753                 unsigned long flags2;
 754                 struct vhci_unlink *unlink;
 755
 756                 spin_lock_irqsave(&vdev->priv_lock, flags2);
 757
 758                 /* setup CMD_UNLINK pdu */
 759                 unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
 760                 if (!unlink) {
 761                         pr_err("malloc vhci_unlink\n");
 762                         spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 763                         spin_unlock_irqrestore(&the_controller->lock, flags);
 764                         usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 765                         return -ENOMEM;
 766                 }
 767
 768                 unlink->seqnum = atomic_inc_return(&the_controller->seqnum);
 769                 if (unlink->seqnum == 0xffff)
 770                         pr_info("seqnum max\n");
 771
 772                 unlink->unlink_seqnum = priv->seqnum;
 773
 774                 pr_info("device %p seems to be still connected\n", vdev);
 775
 776                 /* send cmd_unlink and try to cancel the pending URB in the
 777                  * peer */
 778                 list_add_tail(&unlink->list, &vdev->unlink_tx);
 779                 wake_up(&vdev->waitq_tx);
 780
 781                 spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 782         }
 783
 784         spin_unlock_irqrestore(&the_controller->lock, flags);
 785
 786         usbip_dbg_vhci_hc("leave\n");
 787         return 0;
 788 }
 789
 790 static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
 791 {
 792         struct vhci_unlink *unlink, *tmp;
 793
 794         spin_lock(&vdev->priv_lock);
 795
 796         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
 797                 pr_info("unlink cleanup tx %lu\n", unlink->unlink_seqnum);
 798                 list_del(&unlink->list);
 799                 kfree(unlink);
 800         }
 801
 802         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
 803                 struct urb *urb;
 804
 805                 /* give back URB of unanswered unlink request */
 806                 pr_info("unlink cleanup rx %lu\n", unlink->unlink_seqnum);
 807
 808                 urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
 809                 if (!urb) {
 810                         pr_info("the urb (seqnum %lu) was already given back\n",
 811                                 unlink->unlink_seqnum);
 812                         list_del(&unlink->list);
 813                         kfree(unlink);
 814                         continue;
 815                 }
 816
 817                 urb->status = -ENODEV;
 818
 819                 spin_lock(&the_controller->lock);
 820                 usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
 821                 spin_unlock(&the_controller->lock);
 822
 823                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 824                                      urb->status);
 825
 826                 list_del(&unlink->list);
 827                 kfree(unlink);
 828         }
 829
 830         spin_unlock(&vdev->priv_lock);
 831 }
 832
 833 /*
 834  * The important thing is that only one context begins cleanup.
 835  * This is why error handling and cleanup become simple.
 836  * We do not want to consider race condition as possible.
 837  */
 838 static void vhci_shutdown_connection(struct usbip_device *ud)
 839 {
 840         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 841
 842         /* need this? see stub_dev.c */
 843         if (ud->tcp_socket) {
 844                 pr_debug("shutdown tcp_socket %p\n", ud->tcp_socket);
 845                 kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
 846         }
 847
 848         /* kill threads related to this sdev, if v.c. exists */
 849         kthread_stop(vdev->ud.tcp_rx);
 850         kthread_stop(vdev->ud.tcp_tx);
 851
 852         pr_info("stop threads\n");
 853
 854         /* active connection is closed */
 855         if (vdev->ud.tcp_socket != NULL) {
 856                 sock_release(vdev->ud.tcp_socket);
 857                 vdev->ud.tcp_socket = NULL;
 858         }
 859         pr_info("release socket\n");
 860
 861         vhci_device_unlink_cleanup(vdev);
 862
 863         /*
 864          * rh_port_disconnect() is a trigger of ...
 865          *   usb_disable_device():
 866          *      disable all the endpoints for a USB device.
 867          *   usb_disable_endpoint():
 868          *      disable endpoints. pending urbs are unlinked(dequeued).
 869          *
 870          * NOTE: After calling rh_port_disconnect(), the USB device drivers of a
 871          * deteched device should release used urbs in a cleanup function(i.e.
 872          * xxx_disconnect()). Therefore, vhci_hcd does not need to release
 873          * pushed urbs and their private data in this function.
 874          *
 875          * NOTE: vhci_dequeue() must be considered carefully. When shutdowning
 876          * a connection, vhci_shutdown_connection() expects vhci_dequeue()
 877          * gives back pushed urbs and frees their private data by request of
 878          * the cleanup function of a USB driver. When unlinking a urb with an
 879          * active connection, vhci_dequeue() does not give back the urb which
 880          * is actually given back by vhci_rx after receiving its return pdu.
 881          *
 882          */
 883         rh_port_disconnect(vdev->rhport);
 884
 885         pr_info("disconnect device\n");
 886 }
 887
 888
 889 static void vhci_device_reset(struct usbip_device *ud)
 890 {
 891         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 892
 893         spin_lock(&ud->lock);
 894
 895         vdev->speed  = 0;
 896         vdev->devid  = 0;
 897
 898         if (vdev->udev)
 899                 usb_put_dev(vdev->udev);
 900         vdev->udev = NULL;
 901
 902         ud->tcp_socket = NULL;
 903         ud->status = VDEV_ST_NULL;
 904
 905         spin_unlock(&ud->lock);
 906 }
 907
 908 static void vhci_device_unusable(struct usbip_device *ud)
 909 {
 910         spin_lock(&ud->lock);
 911         ud->status = VDEV_ST_ERROR;
 912         spin_unlock(&ud->lock);
 913 }
 914
 915 static void vhci_device_init(struct vhci_device *vdev)
 916 {
 917         memset(vdev, 0, sizeof(*vdev));
 918
 919         vdev->ud.tcp_rx = kthread_create(vhci_rx_loop, &vdev->ud, "vhci_rx");
 920         vdev->ud.tcp_tx = kthread_create(vhci_tx_loop, &vdev->ud, "vhci_tx");
 921
 922         vdev->ud.side   = USBIP_VHCI;
 923         vdev->ud.status = VDEV_ST_NULL;
 924         /* vdev->ud.lock   = SPIN_LOCK_UNLOCKED; */
 925         spin_lock_init(&vdev->ud.lock);
 926
 927         INIT_LIST_HEAD(&vdev->priv_rx);
 928         INIT_LIST_HEAD(&vdev->priv_tx);
 929         INIT_LIST_HEAD(&vdev->unlink_tx);
 930         INIT_LIST_HEAD(&vdev->unlink_rx);
 931         /* vdev->priv_lock = SPIN_LOCK_UNLOCKED; */
 932         spin_lock_init(&vdev->priv_lock);
 933
 934         init_waitqueue_head(&vdev->waitq_tx);
 935
 936         vdev->ud.eh_ops.shutdown = vhci_shutdown_connection;
 937         vdev->ud.eh_ops.reset = vhci_device_reset;
 938         vdev->ud.eh_ops.unusable = vhci_device_unusable;
 939
 940         usbip_start_eh(&vdev->ud);
 941 }
 942
 943 static int vhci_start(struct usb_hcd *hcd)
 944 {
 945         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 946         int rhport;
 947         int err = 0;
 948
 949         usbip_dbg_vhci_hc("enter vhci_start\n");
 950
 951         /* initialize private data of usb_hcd */
 952
 953         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 954                 struct vhci_device *vdev = &vhci->vdev[rhport];
 955                 vhci_device_init(vdev);
 956                 vdev->rhport = rhport;
 957         }
 958
 959         atomic_set(&vhci->seqnum, 0);
 960         spin_lock_init(&vhci->lock);
 961
 962         hcd->power_budget = 0; /* no limit */
 963         hcd->state  = HC_STATE_RUNNING;
 964         hcd->uses_new_polling = 1;
 965
 966         /* vhci_hcd is now ready to be controlled through sysfs */
 967         err = sysfs_create_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 968         if (err) {
 969                 pr_err("create sysfs files\n");
 970                 return err;
 971         }
 972
 973         return 0;
 974 }
 975
 976 static void vhci_stop(struct usb_hcd *hcd)
 977 {
 978         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 979         int rhport = 0;
 980
 981         usbip_dbg_vhci_hc("stop VHCI controller\n");
 982
 983         /* 1. remove the userland interface of vhci_hcd */
 984         sysfs_remove_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 985
 986         /* 2. shutdown all the ports of vhci_hcd */
 987         for (rhport = 0 ; rhport < VHCI_NPORTS; rhport++) {
 988                 struct vhci_device *vdev = &vhci->vdev[rhport];
 989
 990                 usbip_event_add(&vdev->ud, VDEV_EVENT_REMOVED);
 991                 usbip_stop_eh(&vdev->ud);
 992         }
 993 }
 994
 995 static int vhci_get_frame_number(struct usb_hcd *hcd)
 996 {
 997         pr_err("Not yet implemented\n");
 998         return 0;
 999 }
1000
1001 #ifdef CONFIG_PM
1002
1003 /* FIXME: suspend/resume */
1004 static int vhci_bus_suspend(struct usb_hcd *hcd)
1005 {
1006         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
1007
1008         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1009
1010         spin_lock_irq(&vhci->lock);
1011         /* vhci->rh_state = DUMMY_RH_SUSPENDED;
1012          * set_link_state(vhci); */
1013         hcd->state = HC_STATE_SUSPENDED;
1014         spin_unlock_irq(&vhci->lock);
1015
1016         return 0;
1017 }
1018
1019 static int vhci_bus_resume(struct usb_hcd *hcd)
1020 {
1021         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
1022         int rc = 0;
1023
1024         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1025
1026         spin_lock_irq(&vhci->lock);
1027         if (!HCD_HW_ACCESSIBLE(hcd)) {
1028                 rc = -ESHUTDOWN;
1029         } else {
1030                 /* vhci->rh_state = DUMMY_RH_RUNNING;
1031                  * set_link_state(vhci);
1032                  * if (!list_empty(&vhci->urbp_list))
1033                  *      mod_timer(&vhci->timer, jiffies); */
1034                 hcd->state = HC_STATE_RUNNING;
1035         }
1036         spin_unlock_irq(&vhci->lock);
1037         return rc;
1038
1039         return 0;
1040 }
1041
1042 #else
1043
1044 #define vhci_bus_suspend      NULL
1045 #define vhci_bus_resume       NULL
1046 #endif
1047
1048 static struct hc_driver vhci_hc_driver = {
1049         .description    = driver_name,
1050         .product_desc   = driver_desc,
1051         .hcd_priv_size  = sizeof(struct vhci_hcd),
1052
1053         .flags          = HCD_USB2,
1054
1055         .start          = vhci_start,
1056         .stop           = vhci_stop,
1057
1058         .urb_enqueue    = vhci_urb_enqueue,
1059         .urb_dequeue    = vhci_urb_dequeue,
1060
1061         .get_frame_number = vhci_get_frame_number,
1062
1063         .hub_status_data = vhci_hub_status,
1064         .hub_control    = vhci_hub_control,
1065         .bus_suspend    = vhci_bus_suspend,
1066         .bus_resume     = vhci_bus_resume,
1067 };
1068
1069 static int vhci_hcd_probe(struct platform_device *pdev)
1070 {
1071         struct usb_hcd          *hcd;
1072         int                     ret;
1073
1074         usbip_dbg_vhci_hc("name %s id %d\n", pdev->name, pdev->id);
1075
1076         /* will be removed */
1077         if (pdev->dev.dma_mask) {
1078                 dev_info(&pdev->dev, "vhci_hcd DMA not supported\n");
1079                 return -EINVAL;
1080         }
1081
1082         /*
1083          * Allocate and initialize hcd.
1084          * Our private data is also allocated automatically.
1085          */
1086         hcd = usb_create_hcd(&vhci_hc_driver, &pdev->dev, dev_name(&pdev->dev));
1087         if (!hcd) {
1088                 pr_err("create hcd failed\n");
1089                 return -ENOMEM;
1090         }
1091
1092
1093         /* this is private data for vhci_hcd */
1094         the_controller = hcd_to_vhci(hcd);
1095
1096         /*
1097          * Finish generic HCD structure initialization and register.
1098          * Call the driver's reset() and start() routines.
1099          */
1100         ret = usb_add_hcd(hcd, 0, 0);
1101         if (ret != 0) {
1102                 pr_err("usb_add_hcd failed %d\n", ret);
1103                 usb_put_hcd(hcd);
1104                 the_controller = NULL;
1105                 return ret;
1106         }
1107
1108         usbip_dbg_vhci_hc("bye\n");
1109         return 0;
1110 }
1111
1112 static int vhci_hcd_remove(struct platform_device *pdev)
1113 {
1114         struct usb_hcd  *hcd;
1115
1116         hcd = platform_get_drvdata(pdev);
1117         if (!hcd)
1118                 return 0;
1119
1120         /*
1121          * Disconnects the root hub,
1122          * then reverses the effects of usb_add_hcd(),
1123          * invoking the HCD's stop() methods.
1124          */
1125         usb_remove_hcd(hcd);
1126         usb_put_hcd(hcd);
1127         the_controller = NULL;
1128
1129         return 0;
1130 }
1131
1132 #ifdef CONFIG_PM
1133
1134 /* what should happen for USB/IP under suspend/resume? */
1135 static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
1136 {
1137         struct usb_hcd *hcd;
1138         int rhport = 0;
1139         int connected = 0;
1140         int ret = 0;
1141
1142         hcd = platform_get_drvdata(pdev);
1143
1144         spin_lock(&the_controller->lock);
1145
1146         for (rhport = 0; rhport < VHCI_NPORTS; rhport++)
1147                 if (the_controller->port_status[rhport] &
1148                     USB_PORT_STAT_CONNECTION)
1149                         connected += 1;
1150
1151         spin_unlock(&the_controller->lock);
1152
1153         if (connected > 0) {
1154                 dev_info(&pdev->dev, "We have %d active connection%s. Do not "
1155                          "suspend.\n", connected, (connected == 1 ? "" : "s"));
1156                 ret =  -EBUSY;
1157         } else {
1158                 dev_info(&pdev->dev, "suspend vhci_hcd");
1159                 clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1160         }
1161
1162         return ret;
1163 }
1164
1165 static int vhci_hcd_resume(struct platform_device *pdev)
1166 {
1167         struct usb_hcd *hcd;
1168
1169         dev_dbg(&pdev->dev, "%s\n", __func__);
1170
1171         hcd = platform_get_drvdata(pdev);
1172         set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1173         usb_hcd_poll_rh_status(hcd);
1174
1175         return 0;
1176 }
1177
1178 #else
1179
1180 #define vhci_hcd_suspend        NULL
1181 #define vhci_hcd_resume         NULL
1182
1183 #endif
1184
1185 static struct platform_driver vhci_driver = {
1186         .probe  = vhci_hcd_probe,
1187         .remove = __devexit_p(vhci_hcd_remove),
1188         .suspend = vhci_hcd_suspend,
1189         .resume = vhci_hcd_resume,
1190         .driver = {
1191                 .name = (char *) driver_name,
1192                 .owner = THIS_MODULE,
1193         },
1194 };
1195
1196 /*
1197  * The VHCI 'device' is 'virtual'; not a real plug&play hardware.
1198  * We need to add this virtual device as a platform device arbitrarily:
1199  *      1. platform_device_register()
1200  */
1201 static void the_pdev_release(struct device *dev)
1202 {
1203         return;
1204 }
1205
1206 static struct platform_device the_pdev = {
1207         /* should be the same name as driver_name */
1208         .name = (char *) driver_name,
1209         .id = -1,
1210         .dev = {
1211                 /* .driver = &vhci_driver, */
1212                 .release = the_pdev_release,
1213         },
1214 };
1215
1216 static int __init vhci_init(void)
1217 {
1218         int ret;
1219
1220         if (usb_disabled())
1221                 return -ENODEV;
1222
1223         ret = platform_driver_register(&vhci_driver);
1224         if (ret < 0)
1225                 goto err_driver_register;
1226
1227         ret = platform_device_register(&the_pdev);
1228         if (ret < 0)
1229                 goto err_platform_device_register;
1230
1231         pr_info(DRIVER_DESC " v" USBIP_VERSION "\n");
1232         return ret;
1233
1234 err_platform_device_register:
1235         platform_driver_unregister(&vhci_driver);
1236 err_driver_register:
1237         return ret;
1238 }
1239
1240 static void __exit vhci_cleanup(void)
1241 {
1242         platform_device_unregister(&the_pdev);
1243         platform_driver_unregister(&vhci_driver);
1244 }
1245
1246 module_init(vhci_init);
1247 module_exit(vhci_cleanup);
1248
1249 MODULE_AUTHOR(DRIVER_AUTHOR);
1250 MODULE_DESCRIPTION(DRIVER_DESC);
1251 MODULE_LICENSE("GPL");
1252 MODULE_VERSION(USBIP_VERSION);