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_diff(u32 prev_status, u32 new_status)
  96 {
  97         int i = 0;
  98         u32 bit = 1;
  99
 100         pr_debug("status prev -> new: %08x -> %08x\n", prev_status, new_status);
 101         while (bit) {
 102                 u32 prev = prev_status & bit;
 103                 u32 new = new_status & bit;
 104                 char change;
 105
 106                 if (!prev && new)
 107                         change = '+';
 108                 else if (prev && !new)
 109                         change = '-';
 110                 else
 111                         change = ' ';
 112
 113                 if (prev || new)
 114                         pr_debug(" %c%s\n", change, bit_desc[i]);
 115                 bit <<= 1;
 116                 i++;
 117         }
 118         pr_debug("\n");
 119 }
 120
 121 void rh_port_connect(int rhport, enum usb_device_speed speed)
 122 {
 123         unsigned long   flags;
 124
 125         usbip_dbg_vhci_rh("rh_port_connect %d\n", rhport);
 126
 127         spin_lock_irqsave(&the_controller->lock, flags);
 128
 129         the_controller->port_status[rhport] |= USB_PORT_STAT_CONNECTION
 130                 | (1 << USB_PORT_FEAT_C_CONNECTION);
 131
 132         switch (speed) {
 133         case USB_SPEED_HIGH:
 134                 the_controller->port_status[rhport] |= USB_PORT_STAT_HIGH_SPEED;
 135                 break;
 136         case USB_SPEED_LOW:
 137                 the_controller->port_status[rhport] |= USB_PORT_STAT_LOW_SPEED;
 138                 break;
 139         default:
 140                 break;
 141         }
 142
 143         /* spin_lock(&the_controller->vdev[rhport].ud.lock);
 144          * the_controller->vdev[rhport].ud.status = VDEV_CONNECT;
 145          * spin_unlock(&the_controller->vdev[rhport].ud.lock); */
 146
 147         spin_unlock_irqrestore(&the_controller->lock, flags);
 148
 149         usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 150 }
 151
 152 void rh_port_disconnect(int rhport)
 153 {
 154         unsigned long flags;
 155
 156         usbip_dbg_vhci_rh("rh_port_disconnect %d\n", rhport);
 157
 158         spin_lock_irqsave(&the_controller->lock, flags);
 159         /* stop_activity(dum, driver); */
 160         the_controller->port_status[rhport] &= ~USB_PORT_STAT_CONNECTION;
 161         the_controller->port_status[rhport] |=
 162                                         (1 << USB_PORT_FEAT_C_CONNECTION);
 163
 164         /* not yet complete the disconnection
 165          * spin_lock(&vdev->ud.lock);
 166          * vdev->ud.status = VHC_ST_DISCONNECT;
 167          * spin_unlock(&vdev->ud.lock); */
 168
 169         spin_unlock_irqrestore(&the_controller->lock, flags);
 170         usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 171 }
 172
 173 #define PORT_C_MASK                             \
 174         ((USB_PORT_STAT_C_CONNECTION            \
 175           | USB_PORT_STAT_C_ENABLE              \
 176           | USB_PORT_STAT_C_SUSPEND             \
 177           | USB_PORT_STAT_C_OVERCURRENT         \
 178           | USB_PORT_STAT_C_RESET) << 16)
 179
 180 /*
 181  * This function is almostly the same as dummy_hcd.c:dummy_hub_status() without
 182  * suspend/resume support. But, it is modified to provide multiple ports.
 183  *
 184  * @buf: a bitmap to show which port status has been changed.
 185  *  bit  0: reserved or used for another purpose?
 186  *  bit  1: the status of port 0 has been changed.
 187  *  bit  2: the status of port 1 has been changed.
 188  *  ...
 189  *  bit  7: the status of port 6 has been changed.
 190  *  bit  8: the status of port 7 has been changed.
 191  *  ...
 192  *  bit 15: the status of port 14 has been changed.
 193  *
 194  * So, the maximum number of ports is 31 ( port 0 to port 30) ?
 195  *
 196  * The return value is the actual transferred length in byte. If nothing has
 197  * been changed, return 0. In the case that the number of ports is less than or
 198  * equal to 6 (VHCI_NPORTS==7), return 1.
 199  *
 200  */
 201 static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
 202 {
 203         struct vhci_hcd *vhci;
 204         unsigned long   flags;
 205         int             retval = 0;
 206
 207         /* the enough buffer is allocated according to USB_MAXCHILDREN */
 208         unsigned long   *event_bits = (unsigned long *) buf;
 209         int             rhport;
 210         int             changed = 0;
 211
 212         *event_bits = 0;
 213
 214         vhci = hcd_to_vhci(hcd);
 215
 216         spin_lock_irqsave(&vhci->lock, flags);
 217         if (!HCD_HW_ACCESSIBLE(hcd)) {
 218                 usbip_dbg_vhci_rh("hw accessible flag in on?\n");
 219                 goto done;
 220         }
 221
 222         /* check pseudo status register for each port */
 223         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 224                 if ((vhci->port_status[rhport] & PORT_C_MASK)) {
 225                         /* The status of a port has been changed, */
 226                         usbip_dbg_vhci_rh("port %d is changed\n", rhport);
 227
 228                         *event_bits |= 1 << (rhport + 1);
 229                         changed = 1;
 230                 }
 231         }
 232
 233         pr_info("changed %d\n", changed);
 234
 235         if (hcd->state == HC_STATE_SUSPENDED)
 236                 usb_hcd_resume_root_hub(hcd);
 237
 238         if (changed)
 239                 retval = 1 + (VHCI_NPORTS / 8);
 240         else
 241                 retval = 0;
 242
 243 done:
 244         spin_unlock_irqrestore(&vhci->lock, flags);
 245         return retval;
 246 }
 247
 248 /* See hub_configure in hub.c */
 249 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
 250 {
 251         memset(desc, 0, sizeof(*desc));
 252         desc->bDescriptorType = 0x29;
 253         desc->bDescLength = 9;
 254         desc->wHubCharacteristics = (__force __u16)
 255                 (__constant_cpu_to_le16(0x0001));
 256         desc->bNbrPorts = VHCI_NPORTS;
 257         desc->u.hs.DeviceRemovable[0] = 0xff;
 258         desc->u.hs.DeviceRemovable[1] = 0xff;
 259 }
 260
 261 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 262                             u16 wIndex, char *buf, u16 wLength)
 263 {
 264         struct vhci_hcd *dum;
 265         int             retval = 0;
 266         unsigned long   flags;
 267         int             rhport;
 268
 269         u32 prev_port_status[VHCI_NPORTS];
 270
 271         if (!HCD_HW_ACCESSIBLE(hcd))
 272                 return -ETIMEDOUT;
 273
 274         /*
 275          * NOTE:
 276          * wIndex shows the port number and begins from 1.
 277          */
 278         usbip_dbg_vhci_rh("typeReq %x wValue %x wIndex %x\n", typeReq, wValue,
 279                           wIndex);
 280         if (wIndex > VHCI_NPORTS)
 281                 pr_err("invalid port number %d\n", wIndex);
 282         rhport = ((__u8)(wIndex & 0x00ff)) - 1;
 283
 284         dum = hcd_to_vhci(hcd);
 285
 286         spin_lock_irqsave(&dum->lock, flags);
 287
 288         /* store old status and compare now and old later */
 289         if (usbip_dbg_flag_vhci_rh) {
 290                 memcpy(prev_port_status, dum->port_status,
 291                         sizeof(prev_port_status));
 292         }
 293
 294         switch (typeReq) {
 295         case ClearHubFeature:
 296                 usbip_dbg_vhci_rh(" ClearHubFeature\n");
 297                 break;
 298         case ClearPortFeature:
 299                 switch (wValue) {
 300                 case USB_PORT_FEAT_SUSPEND:
 301                         if (dum->port_status[rhport] & USB_PORT_STAT_SUSPEND) {
 302                                 /* 20msec signaling */
 303                                 dum->resuming = 1;
 304                                 dum->re_timeout =
 305                                         jiffies + msecs_to_jiffies(20);
 306                         }
 307                         break;
 308                 case USB_PORT_FEAT_POWER:
 309                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 310                                           "USB_PORT_FEAT_POWER\n");
 311                         dum->port_status[rhport] = 0;
 312                         /* dum->address = 0; */
 313                         /* dum->hdev = 0; */
 314                         dum->resuming = 0;
 315                         break;
 316                 case USB_PORT_FEAT_C_RESET:
 317                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 318                                           "USB_PORT_FEAT_C_RESET\n");
 319                         switch (dum->vdev[rhport].speed) {
 320                         case USB_SPEED_HIGH:
 321                                 dum->port_status[rhport] |=
 322                                         USB_PORT_STAT_HIGH_SPEED;
 323                                 break;
 324                         case USB_SPEED_LOW:
 325                                 dum->port_status[rhport] |=
 326                                         USB_PORT_STAT_LOW_SPEED;
 327                                 break;
 328                         default:
 329                                 break;
 330                         }
 331                 default:
 332                         usbip_dbg_vhci_rh(" ClearPortFeature: default %x\n",
 333                                           wValue);
 334                         dum->port_status[rhport] &= ~(1 << wValue);
 335                         break;
 336                 }
 337                 break;
 338         case GetHubDescriptor:
 339                 usbip_dbg_vhci_rh(" GetHubDescriptor\n");
 340                 hub_descriptor((struct usb_hub_descriptor *) buf);
 341                 break;
 342         case GetHubStatus:
 343                 usbip_dbg_vhci_rh(" GetHubStatus\n");
 344                 *(__le32 *) buf = __constant_cpu_to_le32(0);
 345                 break;
 346         case GetPortStatus:
 347                 usbip_dbg_vhci_rh(" GetPortStatus port %x\n", wIndex);
 348                 if (wIndex > VHCI_NPORTS || wIndex < 1) {
 349                         pr_err("invalid port number %d\n", wIndex);
 350                         retval = -EPIPE;
 351                 }
 352
 353                 /* we do no care of resume. */
 354
 355                 /* whoever resets or resumes must GetPortStatus to
 356                  * complete it!!
 357                  *                                   */
 358                 if (dum->resuming && time_after(jiffies, dum->re_timeout)) {
 359                         dum->port_status[rhport] |=
 360                                 (1 << USB_PORT_FEAT_C_SUSPEND);
 361                         dum->port_status[rhport] &=
 362                                 ~(1 << USB_PORT_FEAT_SUSPEND);
 363                         dum->resuming = 0;
 364                         dum->re_timeout = 0;
 365                         /* if (dum->driver && dum->driver->resume) {
 366                          *      spin_unlock (&dum->lock);
 367                          *      dum->driver->resume (&dum->gadget);
 368                          *      spin_lock (&dum->lock);
 369                          * } */
 370                 }
 371
 372                 if ((dum->port_status[rhport] & (1 << USB_PORT_FEAT_RESET)) !=
 373                     0 && time_after(jiffies, dum->re_timeout)) {
 374                         dum->port_status[rhport] |=
 375                                 (1 << USB_PORT_FEAT_C_RESET);
 376                         dum->port_status[rhport] &=
 377                                 ~(1 << USB_PORT_FEAT_RESET);
 378                         dum->re_timeout = 0;
 379
 380                         if (dum->vdev[rhport].ud.status ==
 381                             VDEV_ST_NOTASSIGNED) {
 382                                 usbip_dbg_vhci_rh(" enable rhport %d "
 383                                                   "(status %u)\n",
 384                                                   rhport,
 385                                                   dum->vdev[rhport].ud.status);
 386                                 dum->port_status[rhport] |=
 387                                         USB_PORT_STAT_ENABLE;
 388                         }
 389 #if 0
 390                         if (dum->driver) {
 391                                 dum->port_status[rhport] |=
 392                                         USB_PORT_STAT_ENABLE;
 393                                 /* give it the best speed we agree on */
 394                                 dum->gadget.speed = dum->driver->speed;
 395                                 dum->gadget.ep0->maxpacket = 64;
 396                                 switch (dum->gadget.speed) {
 397                                 case USB_SPEED_HIGH:
 398                                         dum->port_status[rhport] |=
 399                                                 USB_PORT_STAT_HIGH_SPEED;
 400                                         break;
 401                                 case USB_SPEED_LOW:
 402                                         dum->gadget.ep0->maxpacket = 8;
 403                                         dum->port_status[rhport] |=
 404                                                 USB_PORT_STAT_LOW_SPEED;
 405                                         break;
 406                                 default:
 407                                         dum->gadget.speed = USB_SPEED_FULL;
 408                                         break;
 409                                 }
 410                         }
 411 #endif
 412                 }
 413                 ((u16 *) buf)[0] = cpu_to_le16(dum->port_status[rhport]);
 414                 ((u16 *) buf)[1] = cpu_to_le16(dum->port_status[rhport] >> 16);
 415
 416                 usbip_dbg_vhci_rh(" GetPortStatus bye %x %x\n", ((u16 *)buf)[0],
 417                                   ((u16 *)buf)[1]);
 418                 break;
 419         case SetHubFeature:
 420                 usbip_dbg_vhci_rh(" SetHubFeature\n");
 421                 retval = -EPIPE;
 422                 break;
 423         case SetPortFeature:
 424                 switch (wValue) {
 425                 case USB_PORT_FEAT_SUSPEND:
 426                         usbip_dbg_vhci_rh(" SetPortFeature: "
 427                                           "USB_PORT_FEAT_SUSPEND\n");
 428 #if 0
 429                         dum->port_status[rhport] |=
 430                                 (1 << USB_PORT_FEAT_SUSPEND);
 431                         if (dum->driver->suspend) {
 432                                 spin_unlock(&dum->lock);
 433                                 dum->driver->suspend(&dum->gadget);
 434                                 spin_lock(&dum->lock);
 435                         }
 436 #endif
 437                         break;
 438                 case USB_PORT_FEAT_RESET:
 439                         usbip_dbg_vhci_rh(" SetPortFeature: "
 440                                           "USB_PORT_FEAT_RESET\n");
 441                         /* if it's already running, disconnect first */
 442                         if (dum->port_status[rhport] & USB_PORT_STAT_ENABLE) {
 443                                 dum->port_status[rhport] &=
 444                                         ~(USB_PORT_STAT_ENABLE |
 445                                           USB_PORT_STAT_LOW_SPEED |
 446                                           USB_PORT_STAT_HIGH_SPEED);
 447 #if 0
 448                                 if (dum->driver) {
 449                                         dev_dbg(hardware, "disconnect\n");
 450                                         stop_activity(dum, dum->driver);
 451                                 }
 452 #endif
 453
 454                                 /* FIXME test that code path! */
 455                         }
 456                         /* 50msec reset signaling */
 457                         dum->re_timeout = jiffies + msecs_to_jiffies(50);
 458
 459                         /* FALLTHROUGH */
 460                 default:
 461                         usbip_dbg_vhci_rh(" SetPortFeature: default %d\n",
 462                                           wValue);
 463                         dum->port_status[rhport] |= (1 << wValue);
 464                         break;
 465                 }
 466                 break;
 467
 468         default:
 469                 pr_err("default: no such request\n");
 470                 /* dev_dbg (hardware,
 471                  *              "hub control req%04x v%04x i%04x l%d\n",
 472                  *              typeReq, wValue, wIndex, wLength); */
 473
 474                 /* "protocol stall" on error */
 475                 retval = -EPIPE;
 476         }
 477
 478         if (usbip_dbg_flag_vhci_rh) {
 479                 pr_debug("port %d\n", rhport);
 480                 /* Only dump valid port status */
 481                 if (rhport >= 0) {
 482                         dump_port_status_diff(prev_port_status[rhport],
 483                                               dum->port_status[rhport]);
 484                 }
 485         }
 486         usbip_dbg_vhci_rh(" bye\n");
 487
 488         spin_unlock_irqrestore(&dum->lock, flags);
 489
 490         return retval;
 491 }
 492
 493 static struct vhci_device *get_vdev(struct usb_device *udev)
 494 {
 495         int i;
 496
 497         if (!udev)
 498                 return NULL;
 499
 500         for (i = 0; i < VHCI_NPORTS; i++)
 501                 if (the_controller->vdev[i].udev == udev)
 502                         return port_to_vdev(i);
 503
 504         return NULL;
 505 }
 506
 507 static void vhci_tx_urb(struct urb *urb)
 508 {
 509         struct vhci_device *vdev = get_vdev(urb->dev);
 510         struct vhci_priv *priv;
 511         unsigned long flag;
 512
 513         if (!vdev) {
 514                 pr_err("could not get virtual device");
 515                 /* BUG(); */
 516                 return;
 517         }
 518
 519         priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
 520
 521         spin_lock_irqsave(&vdev->priv_lock, flag);
 522
 523         if (!priv) {
 524                 dev_err(&urb->dev->dev, "malloc vhci_priv\n");
 525                 spin_unlock_irqrestore(&vdev->priv_lock, flag);
 526                 usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 527                 return;
 528         }
 529
 530         priv->seqnum = atomic_inc_return(&the_controller->seqnum);
 531         if (priv->seqnum == 0xffff)
 532                 dev_info(&urb->dev->dev, "seqnum max\n");
 533
 534         priv->vdev = vdev;
 535         priv->urb = urb;
 536
 537         urb->hcpriv = (void *) priv;
 538
 539         list_add_tail(&priv->list, &vdev->priv_tx);
 540
 541         wake_up(&vdev->waitq_tx);
 542         spin_unlock_irqrestore(&vdev->priv_lock, flag);
 543 }
 544
 545 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 546                             gfp_t mem_flags)
 547 {
 548         struct device *dev = &urb->dev->dev;
 549         int ret = 0;
 550         unsigned long flags;
 551         struct vhci_device *vdev;
 552
 553         usbip_dbg_vhci_hc("enter, usb_hcd %p urb %p mem_flags %d\n",
 554                           hcd, urb, mem_flags);
 555
 556         /* patch to usb_sg_init() is in 2.5.60 */
 557         BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);
 558
 559         spin_lock_irqsave(&the_controller->lock, flags);
 560
 561         if (urb->status != -EINPROGRESS) {
 562                 dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
 563                 spin_unlock_irqrestore(&the_controller->lock, flags);
 564                 return urb->status;
 565         }
 566
 567         vdev = port_to_vdev(urb->dev->portnum-1);
 568
 569         /* refuse enqueue for dead connection */
 570         spin_lock(&vdev->ud.lock);
 571         if (vdev->ud.status == VDEV_ST_NULL ||
 572             vdev->ud.status == VDEV_ST_ERROR) {
 573                 dev_err(dev, "enqueue for inactive port %d\n", vdev->rhport);
 574                 spin_unlock(&vdev->ud.lock);
 575                 spin_unlock_irqrestore(&the_controller->lock, flags);
 576                 return -ENODEV;
 577         }
 578         spin_unlock(&vdev->ud.lock);
 579
 580         ret = usb_hcd_link_urb_to_ep(hcd, urb);
 581         if (ret)
 582                 goto no_need_unlink;
 583
 584         /*
 585          * The enumeration process is as follows;
 586          *
 587          *  1. Get_Descriptor request to DevAddrs(0) EndPoint(0)
 588          *     to get max packet length of default pipe
 589          *
 590          *  2. Set_Address request to DevAddr(0) EndPoint(0)
 591          *
 592          */
 593         if (usb_pipedevice(urb->pipe) == 0) {
 594                 __u8 type = usb_pipetype(urb->pipe);
 595                 struct usb_ctrlrequest *ctrlreq =
 596                         (struct usb_ctrlrequest *) urb->setup_packet;
 597
 598                 if (type != PIPE_CONTROL || !ctrlreq) {
 599                         dev_err(dev, "invalid request to devnum 0\n");
 600                         ret = -EINVAL;
 601                         goto no_need_xmit;
 602                 }
 603
 604                 switch (ctrlreq->bRequest) {
 605                 case USB_REQ_SET_ADDRESS:
 606                         /* set_address may come when a device is reset */
 607                         dev_info(dev, "SetAddress Request (%d) to port %d\n",
 608                                  ctrlreq->wValue, vdev->rhport);
 609
 610                         if (vdev->udev)
 611                                 usb_put_dev(vdev->udev);
 612                         vdev->udev = usb_get_dev(urb->dev);
 613
 614                         spin_lock(&vdev->ud.lock);
 615                         vdev->ud.status = VDEV_ST_USED;
 616                         spin_unlock(&vdev->ud.lock);
 617
 618                         if (urb->status == -EINPROGRESS) {
 619                                 /* This request is successfully completed. */
 620                                 /* If not -EINPROGRESS, possibly unlinked. */
 621                                 urb->status = 0;
 622                         }
 623
 624                         goto no_need_xmit;
 625
 626                 case USB_REQ_GET_DESCRIPTOR:
 627                         if (ctrlreq->wValue == (USB_DT_DEVICE << 8))
 628                                 usbip_dbg_vhci_hc("Not yet?: "
 629                                                   "Get_Descriptor to device 0 "
 630                                                   "(get max pipe size)\n");
 631
 632                         if (vdev->udev)
 633                                 usb_put_dev(vdev->udev);
 634                         vdev->udev = usb_get_dev(urb->dev);
 635                         goto out;
 636
 637                 default:
 638                         /* NOT REACHED */
 639                         dev_err(dev, "invalid request to devnum 0 bRequest %u, "
 640                                 "wValue %u\n", ctrlreq->bRequest,
 641                                 ctrlreq->wValue);
 642                         ret =  -EINVAL;
 643                         goto no_need_xmit;
 644                 }
 645
 646         }
 647
 648 out:
 649         vhci_tx_urb(urb);
 650         spin_unlock_irqrestore(&the_controller->lock, flags);
 651
 652         return 0;
 653
 654 no_need_xmit:
 655         usb_hcd_unlink_urb_from_ep(hcd, urb);
 656 no_need_unlink:
 657         spin_unlock_irqrestore(&the_controller->lock, flags);
 658         usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
 659         return ret;
 660 }
 661
 662 /*
 663  * vhci_rx gives back the urb after receiving the reply of the urb.  If an
 664  * unlink pdu is sent or not, vhci_rx receives a normal return pdu and gives
 665  * back its urb. For the driver unlinking the urb, the content of the urb is
 666  * not important, but the calling to its completion handler is important; the
 667  * completion of unlinking is notified by the completion handler.
 668  *
 669  *
 670  * CLIENT SIDE
 671  *
 672  * - When vhci_hcd receives RET_SUBMIT,
 673  *
 674  *      - case 1a). the urb of the pdu is not unlinking.
 675  *              - normal case
 676  *              => just give back the urb
 677  *
 678  *      - case 1b). the urb of the pdu is unlinking.
 679  *              - usbip.ko will return a reply of the unlinking request.
 680  *              => give back the urb now and go to case 2b).
 681  *
 682  * - When vhci_hcd receives RET_UNLINK,
 683  *
 684  *      - case 2a). a submit request is still pending in vhci_hcd.
 685  *              - urb was really pending in usbip.ko and urb_unlink_urb() was
 686  *                completed there.
 687  *              => free a pending submit request
 688  *              => notify unlink completeness by giving back the urb
 689  *
 690  *      - case 2b). a submit request is *not* pending in vhci_hcd.
 691  *              - urb was already given back to the core driver.
 692  *              => do not give back the urb
 693  *
 694  *
 695  * SERVER SIDE
 696  *
 697  * - When usbip receives CMD_UNLINK,
 698  *
 699  *      - case 3a). the urb of the unlink request is now in submission.
 700  *              => do usb_unlink_urb().
 701  *              => after the unlink is completed, send RET_UNLINK.
 702  *
 703  *      - case 3b). the urb of the unlink request is not in submission.
 704  *              - may be already completed or never be received
 705  *              => send RET_UNLINK
 706  *
 707  */
 708 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 709 {
 710         unsigned long flags;
 711         struct vhci_priv *priv;
 712         struct vhci_device *vdev;
 713
 714         pr_info("dequeue a urb %p\n", urb);
 715
 716         spin_lock_irqsave(&the_controller->lock, flags);
 717
 718         priv = urb->hcpriv;
 719         if (!priv) {
 720                 /* URB was never linked! or will be soon given back by
 721                  * vhci_rx. */
 722                 spin_unlock_irqrestore(&the_controller->lock, flags);
 723                 return 0;
 724         }
 725
 726         {
 727                 int ret = 0;
 728                 ret = usb_hcd_check_unlink_urb(hcd, urb, status);
 729                 if (ret) {
 730                         spin_unlock_irqrestore(&the_controller->lock, flags);
 731                         return ret;
 732                 }
 733         }
 734
 735          /* send unlink request here? */
 736         vdev = priv->vdev;
 737
 738         if (!vdev->ud.tcp_socket) {
 739                 /* tcp connection is closed */
 740                 unsigned long flags2;
 741
 742                 spin_lock_irqsave(&vdev->priv_lock, flags2);
 743
 744                 pr_info("device %p seems to be disconnected\n", vdev);
 745                 list_del(&priv->list);
 746                 kfree(priv);
 747                 urb->hcpriv = NULL;
 748
 749                 spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 750
 751                 /*
 752                  * If tcp connection is alive, we have sent CMD_UNLINK.
 753                  * vhci_rx will receive RET_UNLINK and give back the URB.
 754                  * Otherwise, we give back it here.
 755                  */
 756                 pr_info("gives back urb %p\n", urb);
 757
 758                 usb_hcd_unlink_urb_from_ep(hcd, urb);
 759
 760                 spin_unlock_irqrestore(&the_controller->lock, flags);
 761                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 762                                      urb->status);
 763                 spin_lock_irqsave(&the_controller->lock, flags);
 764
 765         } else {
 766                 /* tcp connection is alive */
 767                 unsigned long flags2;
 768                 struct vhci_unlink *unlink;
 769
 770                 spin_lock_irqsave(&vdev->priv_lock, flags2);
 771
 772                 /* setup CMD_UNLINK pdu */
 773                 unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
 774                 if (!unlink) {
 775                         pr_err("malloc vhci_unlink\n");
 776                         spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 777                         spin_unlock_irqrestore(&the_controller->lock, flags);
 778                         usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 779                         return -ENOMEM;
 780                 }
 781
 782                 unlink->seqnum = atomic_inc_return(&the_controller->seqnum);
 783                 if (unlink->seqnum == 0xffff)
 784                         pr_info("seqnum max\n");
 785
 786                 unlink->unlink_seqnum = priv->seqnum;
 787
 788                 pr_info("device %p seems to be still connected\n", vdev);
 789
 790                 /* send cmd_unlink and try to cancel the pending URB in the
 791                  * peer */
 792                 list_add_tail(&unlink->list, &vdev->unlink_tx);
 793                 wake_up(&vdev->waitq_tx);
 794
 795                 spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 796         }
 797
 798         spin_unlock_irqrestore(&the_controller->lock, flags);
 799
 800         usbip_dbg_vhci_hc("leave\n");
 801         return 0;
 802 }
 803
 804 static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
 805 {
 806         struct vhci_unlink *unlink, *tmp;
 807
 808         spin_lock(&vdev->priv_lock);
 809
 810         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
 811                 pr_info("unlink cleanup tx %lu\n", unlink->unlink_seqnum);
 812                 list_del(&unlink->list);
 813                 kfree(unlink);
 814         }
 815
 816         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
 817                 struct urb *urb;
 818
 819                 /* give back URB of unanswered unlink request */
 820                 pr_info("unlink cleanup rx %lu\n", unlink->unlink_seqnum);
 821
 822                 urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
 823                 if (!urb) {
 824                         pr_info("the urb (seqnum %lu) was already given back\n",
 825                                 unlink->unlink_seqnum);
 826                         list_del(&unlink->list);
 827                         kfree(unlink);
 828                         continue;
 829                 }
 830
 831                 urb->status = -ENODEV;
 832
 833                 spin_lock(&the_controller->lock);
 834                 usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
 835                 spin_unlock(&the_controller->lock);
 836
 837                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 838                                      urb->status);
 839
 840                 list_del(&unlink->list);
 841                 kfree(unlink);
 842         }
 843
 844         spin_unlock(&vdev->priv_lock);
 845 }
 846
 847 /*
 848  * The important thing is that only one context begins cleanup.
 849  * This is why error handling and cleanup become simple.
 850  * We do not want to consider race condition as possible.
 851  */
 852 static void vhci_shutdown_connection(struct usbip_device *ud)
 853 {
 854         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 855
 856         /* need this? see stub_dev.c */
 857         if (ud->tcp_socket) {
 858                 pr_debug("shutdown tcp_socket %p\n", ud->tcp_socket);
 859                 kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
 860         }
 861
 862         /* kill threads related to this sdev, if v.c. exists */
 863         if (vdev->ud.tcp_rx && !task_is_dead(vdev->ud.tcp_rx))
 864                 kthread_stop(vdev->ud.tcp_rx);
 865         if (vdev->ud.tcp_tx && !task_is_dead(vdev->ud.tcp_tx))
 866                 kthread_stop(vdev->ud.tcp_tx);
 867
 868         pr_info("stop threads\n");
 869
 870         /* active connection is closed */
 871         if (vdev->ud.tcp_socket != NULL) {
 872                 sock_release(vdev->ud.tcp_socket);
 873                 vdev->ud.tcp_socket = NULL;
 874         }
 875         pr_info("release socket\n");
 876
 877         vhci_device_unlink_cleanup(vdev);
 878
 879         /*
 880          * rh_port_disconnect() is a trigger of ...
 881          *   usb_disable_device():
 882          *      disable all the endpoints for a USB device.
 883          *   usb_disable_endpoint():
 884          *      disable endpoints. pending urbs are unlinked(dequeued).
 885          *
 886          * NOTE: After calling rh_port_disconnect(), the USB device drivers of a
 887          * deteched device should release used urbs in a cleanup function(i.e.
 888          * xxx_disconnect()). Therefore, vhci_hcd does not need to release
 889          * pushed urbs and their private data in this function.
 890          *
 891          * NOTE: vhci_dequeue() must be considered carefully. When shutdowning
 892          * a connection, vhci_shutdown_connection() expects vhci_dequeue()
 893          * gives back pushed urbs and frees their private data by request of
 894          * the cleanup function of a USB driver. When unlinking a urb with an
 895          * active connection, vhci_dequeue() does not give back the urb which
 896          * is actually given back by vhci_rx after receiving its return pdu.
 897          *
 898          */
 899         rh_port_disconnect(vdev->rhport);
 900
 901         pr_info("disconnect device\n");
 902 }
 903
 904
 905 static void vhci_device_reset(struct usbip_device *ud)
 906 {
 907         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 908
 909         spin_lock(&ud->lock);
 910
 911         vdev->speed  = 0;
 912         vdev->devid  = 0;
 913
 914         if (vdev->udev)
 915                 usb_put_dev(vdev->udev);
 916         vdev->udev = NULL;
 917
 918         ud->tcp_socket = NULL;
 919         ud->status = VDEV_ST_NULL;
 920
 921         spin_unlock(&ud->lock);
 922 }
 923
 924 static void vhci_device_unusable(struct usbip_device *ud)
 925 {
 926         spin_lock(&ud->lock);
 927         ud->status = VDEV_ST_ERROR;
 928         spin_unlock(&ud->lock);
 929 }
 930
 931 static void vhci_device_init(struct vhci_device *vdev)
 932 {
 933         memset(vdev, 0, sizeof(*vdev));
 934
 935         vdev->ud.side   = USBIP_VHCI;
 936         vdev->ud.status = VDEV_ST_NULL;
 937         /* vdev->ud.lock   = SPIN_LOCK_UNLOCKED; */
 938         spin_lock_init(&vdev->ud.lock);
 939
 940         INIT_LIST_HEAD(&vdev->priv_rx);
 941         INIT_LIST_HEAD(&vdev->priv_tx);
 942         INIT_LIST_HEAD(&vdev->unlink_tx);
 943         INIT_LIST_HEAD(&vdev->unlink_rx);
 944         /* vdev->priv_lock = SPIN_LOCK_UNLOCKED; */
 945         spin_lock_init(&vdev->priv_lock);
 946
 947         init_waitqueue_head(&vdev->waitq_tx);
 948
 949         vdev->ud.eh_ops.shutdown = vhci_shutdown_connection;
 950         vdev->ud.eh_ops.reset = vhci_device_reset;
 951         vdev->ud.eh_ops.unusable = vhci_device_unusable;
 952
 953         usbip_start_eh(&vdev->ud);
 954 }
 955
 956 static int vhci_start(struct usb_hcd *hcd)
 957 {
 958         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 959         int rhport;
 960         int err = 0;
 961
 962         usbip_dbg_vhci_hc("enter vhci_start\n");
 963
 964         /* initialize private data of usb_hcd */
 965
 966         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 967                 struct vhci_device *vdev = &vhci->vdev[rhport];
 968                 vhci_device_init(vdev);
 969                 vdev->rhport = rhport;
 970         }
 971
 972         atomic_set(&vhci->seqnum, 0);
 973         spin_lock_init(&vhci->lock);
 974
 975         hcd->power_budget = 0; /* no limit */
 976         hcd->state  = HC_STATE_RUNNING;
 977         hcd->uses_new_polling = 1;
 978
 979         /* vhci_hcd is now ready to be controlled through sysfs */
 980         err = sysfs_create_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 981         if (err) {
 982                 pr_err("create sysfs files\n");
 983                 return err;
 984         }
 985
 986         return 0;
 987 }
 988
 989 static void vhci_stop(struct usb_hcd *hcd)
 990 {
 991         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 992         int rhport = 0;
 993
 994         usbip_dbg_vhci_hc("stop VHCI controller\n");
 995
 996         /* 1. remove the userland interface of vhci_hcd */
 997         sysfs_remove_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 998
 999         /* 2. shutdown all the ports of vhci_hcd */
1000         for (rhport = 0 ; rhport < VHCI_NPORTS; rhport++) {
1001                 struct vhci_device *vdev = &vhci->vdev[rhport];
1002
1003                 usbip_event_add(&vdev->ud, VDEV_EVENT_REMOVED);
1004                 usbip_stop_eh(&vdev->ud);
1005         }
1006 }
1007
1008 static int vhci_get_frame_number(struct usb_hcd *hcd)
1009 {
1010         pr_err("Not yet implemented\n");
1011         return 0;
1012 }
1013
1014 #ifdef CONFIG_PM
1015
1016 /* FIXME: suspend/resume */
1017 static int vhci_bus_suspend(struct usb_hcd *hcd)
1018 {
1019         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
1020
1021         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1022
1023         spin_lock_irq(&vhci->lock);
1024         /* vhci->rh_state = DUMMY_RH_SUSPENDED;
1025          * set_link_state(vhci); */
1026         hcd->state = HC_STATE_SUSPENDED;
1027         spin_unlock_irq(&vhci->lock);
1028
1029         return 0;
1030 }
1031
1032 static int vhci_bus_resume(struct usb_hcd *hcd)
1033 {
1034         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
1035         int rc = 0;
1036
1037         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1038
1039         spin_lock_irq(&vhci->lock);
1040         if (!HCD_HW_ACCESSIBLE(hcd)) {
1041                 rc = -ESHUTDOWN;
1042         } else {
1043                 /* vhci->rh_state = DUMMY_RH_RUNNING;
1044                  * set_link_state(vhci);
1045                  * if (!list_empty(&vhci->urbp_list))
1046                  *      mod_timer(&vhci->timer, jiffies); */
1047                 hcd->state = HC_STATE_RUNNING;
1048         }
1049         spin_unlock_irq(&vhci->lock);
1050
1051         return rc;
1052 }
1053
1054 #else
1055
1056 #define vhci_bus_suspend      NULL
1057 #define vhci_bus_resume       NULL
1058 #endif
1059
1060 static struct hc_driver vhci_hc_driver = {
1061         .description    = driver_name,
1062         .product_desc   = driver_desc,
1063         .hcd_priv_size  = sizeof(struct vhci_hcd),
1064
1065         .flags          = HCD_USB2,
1066
1067         .start          = vhci_start,
1068         .stop           = vhci_stop,
1069
1070         .urb_enqueue    = vhci_urb_enqueue,
1071         .urb_dequeue    = vhci_urb_dequeue,
1072
1073         .get_frame_number = vhci_get_frame_number,
1074
1075         .hub_status_data = vhci_hub_status,
1076         .hub_control    = vhci_hub_control,
1077         .bus_suspend    = vhci_bus_suspend,
1078         .bus_resume     = vhci_bus_resume,
1079 };
1080
1081 static int vhci_hcd_probe(struct platform_device *pdev)
1082 {
1083         struct usb_hcd          *hcd;
1084         int                     ret;
1085
1086         usbip_dbg_vhci_hc("name %s id %d\n", pdev->name, pdev->id);
1087
1088         /* will be removed */
1089         if (pdev->dev.dma_mask) {
1090                 dev_info(&pdev->dev, "vhci_hcd DMA not supported\n");
1091                 return -EINVAL;
1092         }
1093
1094         /*
1095          * Allocate and initialize hcd.
1096          * Our private data is also allocated automatically.
1097          */
1098         hcd = usb_create_hcd(&vhci_hc_driver, &pdev->dev, dev_name(&pdev->dev));
1099         if (!hcd) {
1100                 pr_err("create hcd failed\n");
1101                 return -ENOMEM;
1102         }
1103         hcd->has_tt = 1;
1104
1105         /* this is private data for vhci_hcd */
1106         the_controller = hcd_to_vhci(hcd);
1107
1108         /*
1109          * Finish generic HCD structure initialization and register.
1110          * Call the driver's reset() and start() routines.
1111          */
1112         ret = usb_add_hcd(hcd, 0, 0);
1113         if (ret != 0) {
1114                 pr_err("usb_add_hcd failed %d\n", ret);
1115                 usb_put_hcd(hcd);
1116                 the_controller = NULL;
1117                 return ret;
1118         }
1119
1120         usbip_dbg_vhci_hc("bye\n");
1121         return 0;
1122 }
1123
1124 static int vhci_hcd_remove(struct platform_device *pdev)
1125 {
1126         struct usb_hcd  *hcd;
1127
1128         hcd = platform_get_drvdata(pdev);
1129         if (!hcd)
1130                 return 0;
1131
1132         /*
1133          * Disconnects the root hub,
1134          * then reverses the effects of usb_add_hcd(),
1135          * invoking the HCD's stop() methods.
1136          */
1137         usb_remove_hcd(hcd);
1138         usb_put_hcd(hcd);
1139         the_controller = NULL;
1140
1141         return 0;
1142 }
1143
1144 #ifdef CONFIG_PM
1145
1146 /* what should happen for USB/IP under suspend/resume? */
1147 static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
1148 {
1149         struct usb_hcd *hcd;
1150         int rhport = 0;
1151         int connected = 0;
1152         int ret = 0;
1153
1154         hcd = platform_get_drvdata(pdev);
1155
1156         spin_lock(&the_controller->lock);
1157
1158         for (rhport = 0; rhport < VHCI_NPORTS; rhport++)
1159                 if (the_controller->port_status[rhport] &
1160                     USB_PORT_STAT_CONNECTION)
1161                         connected += 1;
1162
1163         spin_unlock(&the_controller->lock);
1164
1165         if (connected > 0) {
1166                 dev_info(&pdev->dev, "We have %d active connection%s. Do not "
1167                          "suspend.\n", connected, (connected == 1 ? "" : "s"));
1168                 ret =  -EBUSY;
1169         } else {
1170                 dev_info(&pdev->dev, "suspend vhci_hcd");
1171                 clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1172         }
1173
1174         return ret;
1175 }
1176
1177 static int vhci_hcd_resume(struct platform_device *pdev)
1178 {
1179         struct usb_hcd *hcd;
1180
1181         dev_dbg(&pdev->dev, "%s\n", __func__);
1182
1183         hcd = platform_get_drvdata(pdev);
1184         set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1185         usb_hcd_poll_rh_status(hcd);
1186
1187         return 0;
1188 }
1189
1190 #else
1191
1192 #define vhci_hcd_suspend        NULL
1193 #define vhci_hcd_resume         NULL
1194
1195 #endif
1196
1197 static struct platform_driver vhci_driver = {
1198         .probe  = vhci_hcd_probe,
1199         .remove = __devexit_p(vhci_hcd_remove),
1200         .suspend = vhci_hcd_suspend,
1201         .resume = vhci_hcd_resume,
1202         .driver = {
1203                 .name = (char *) driver_name,
1204                 .owner = THIS_MODULE,
1205         },
1206 };
1207
1208 /*
1209  * The VHCI 'device' is 'virtual'; not a real plug&play hardware.
1210  * We need to add this virtual device as a platform device arbitrarily:
1211  *      1. platform_device_register()
1212  */
1213 static void the_pdev_release(struct device *dev)
1214 {
1215         return;
1216 }
1217
1218 static struct platform_device the_pdev = {
1219         /* should be the same name as driver_name */
1220         .name = (char *) driver_name,
1221         .id = -1,
1222         .dev = {
1223                 /* .driver = &vhci_driver, */
1224                 .release = the_pdev_release,
1225         },
1226 };
1227
1228 static int __init vhci_hcd_init(void)
1229 {
1230         int ret;
1231
1232         if (usb_disabled())
1233                 return -ENODEV;
1234
1235         ret = platform_driver_register(&vhci_driver);
1236         if (ret < 0)
1237                 goto err_driver_register;
1238
1239         ret = platform_device_register(&the_pdev);
1240         if (ret < 0)
1241                 goto err_platform_device_register;
1242
1243         pr_info(DRIVER_DESC " v" USBIP_VERSION "\n");
1244         return ret;
1245
1246 err_platform_device_register:
1247         platform_driver_unregister(&vhci_driver);
1248 err_driver_register:
1249         return ret;
1250 }
1251
1252 static void __exit vhci_hcd_exit(void)
1253 {
1254         platform_device_unregister(&the_pdev);
1255         platform_driver_unregister(&vhci_driver);
1256 }
1257
1258 module_init(vhci_hcd_init);
1259 module_exit(vhci_hcd_exit);
1260
1261 MODULE_AUTHOR(DRIVER_AUTHOR);
1262 MODULE_DESCRIPTION(DRIVER_DESC);
1263 MODULE_LICENSE("GPL");
1264 MODULE_VERSION(USBIP_VERSION);