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/slab.h>
  21
  22 #include "usbip_common.h"
  23 #include "vhci.h"
  24
  25 #define DRIVER_VERSION "1.0"
  26 #define DRIVER_AUTHOR "Takahiro Hirofuchi"
  27 #define DRIVER_DESC "Virtual Host Controller Interface Driver for USB/IP"
  28 #define DRIVER_LICENCE "GPL"
  29 MODULE_AUTHOR(DRIVER_AUTHOR);
  30 MODULE_DESCRIPTION(DRIVER_DESC);
  31 MODULE_LICENSE(DRIVER_LICENCE);
  32
  33
  34
  35 /*
  36  * TODO
  37  *      - update root hub emulation
  38  *      - move the emulation code to userland ?
  39  *              porting to other operating systems
  40  *              minimize kernel code
  41  *      - add suspend/resume code
  42  *      - clean up everything
  43  */
  44
  45
  46 /* See usb gadget dummy hcd */
  47
  48
  49 static int vhci_hub_status(struct usb_hcd *hcd, char *buff);
  50 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
  51                 u16 wIndex, char *buff, u16 wLength);
  52 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
  53                                                         gfp_t mem_flags);
  54 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status);
  55 static int vhci_start(struct usb_hcd *vhci_hcd);
  56 static void vhci_stop(struct usb_hcd *hcd);
  57 static int vhci_get_frame_number(struct usb_hcd *hcd);
  58
  59 static const char driver_name[] = "vhci_hcd";
  60 static const char driver_desc[] = "USB/IP Virtual Host Controller";
  61
  62 struct vhci_hcd *the_controller;
  63
  64 static const char *bit_desc[] = {
  65         "CONNECTION",           /*0*/
  66         "ENABLE",               /*1*/
  67         "SUSPEND",              /*2*/
  68         "OVER_CURRENT",         /*3*/
  69         "RESET",                /*4*/
  70         "R5",           /*5*/
  71         "R6",           /*6*/
  72         "R7",           /*7*/
  73         "POWER",                /*8*/
  74         "LOWSPEED",             /*9*/
  75         "HIGHSPEED",            /*10*/
  76         "PORT_TEST",            /*11*/
  77         "INDICATOR",            /*12*/
  78         "R13",          /*13*/
  79         "R14",          /*14*/
  80         "R15",          /*15*/
  81         "C_CONNECTION",         /*16*/
  82         "C_ENABLE",             /*17*/
  83         "C_SUSPEND",            /*18*/
  84         "C_OVER_CURRENT",       /*19*/
  85         "C_RESET",              /*20*/
  86         "R21",          /*21*/
  87         "R22",          /*22*/
  88         "R23",          /*23*/
  89         "R24",          /*24*/
  90         "R25",          /*25*/
  91         "R26",          /*26*/
  92         "R27",          /*27*/
  93         "R28",          /*28*/
  94         "R29",          /*29*/
  95         "R30",          /*30*/
  96         "R31",          /*31*/
  97 };
  98
  99
 100 static void dump_port_status(u32 status)
 101 {
 102         int i = 0;
 103
 104         printk(KERN_DEBUG "status %08x:", status);
 105         for (i = 0; i < 32; i++) {
 106                 if (status & (1 << i))
 107                         printk(" %s", bit_desc[i]);
 108         }
 109
 110         printk("\n");
 111 }
 112
 113
 114
 115 void rh_port_connect(int rhport, enum usb_device_speed speed)
 116 {
 117         unsigned long   flags;
 118
 119         usbip_dbg_vhci_rh("rh_port_connect %d\n", rhport);
 120
 121         spin_lock_irqsave(&the_controller->lock, flags);
 122
 123         the_controller->port_status[rhport] |= USB_PORT_STAT_CONNECTION
 124                 | (1 << USB_PORT_FEAT_C_CONNECTION);
 125
 126         switch (speed) {
 127         case USB_SPEED_HIGH:
 128                 the_controller->port_status[rhport] |= USB_PORT_STAT_HIGH_SPEED;
 129                 break;
 130         case USB_SPEED_LOW:
 131                 the_controller->port_status[rhport] |= USB_PORT_STAT_LOW_SPEED;
 132                 break;
 133         default:
 134                 break;
 135         }
 136
 137         /* spin_lock(&the_controller->vdev[rhport].ud.lock);
 138          * the_controller->vdev[rhport].ud.status = VDEV_CONNECT;
 139          * spin_unlock(&the_controller->vdev[rhport].ud.lock); */
 140
 141         the_controller->pending_port = rhport;
 142
 143         spin_unlock_irqrestore(&the_controller->lock, flags);
 144
 145         usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 146 }
 147
 148 void rh_port_disconnect(int rhport)
 149 {
 150         unsigned long flags;
 151
 152         usbip_dbg_vhci_rh("rh_port_disconnect %d\n", rhport);
 153
 154         spin_lock_irqsave(&the_controller->lock, flags);
 155         /* stop_activity(dum, driver); */
 156         the_controller->port_status[rhport] &= ~USB_PORT_STAT_CONNECTION;
 157         the_controller->port_status[rhport] |=
 158                                         (1 << USB_PORT_FEAT_C_CONNECTION);
 159
 160
 161         /* not yet complete the disconnection
 162          * spin_lock(&vdev->ud.lock);
 163          * vdev->ud.status = VHC_ST_DISCONNECT;
 164          * spin_unlock(&vdev->ud.lock); */
 165
 166         spin_unlock_irqrestore(&the_controller->lock, flags);
 167
 168         usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
 169 }
 170
 171
 172
 173 /*----------------------------------------------------------------------*/
 174
 175 #define PORT_C_MASK \
 176         ((USB_PORT_STAT_C_CONNECTION \
 177           | USB_PORT_STAT_C_ENABLE \
 178           | USB_PORT_STAT_C_SUSPEND \
 179           | USB_PORT_STAT_C_OVERCURRENT \
 180           | USB_PORT_STAT_C_RESET) << 16)
 181
 182 /*
 183  * This function is almostly the same as dummy_hcd.c:dummy_hub_status() without
 184  * suspend/resume support. But, it is modified to provide multiple ports.
 185  *
 186  * @buf: a bitmap to show which port status has been changed.
 187  *  bit  0: reserved or used for another purpose?
 188  *  bit  1: the status of port 0 has been changed.
 189  *  bit  2: the status of port 1 has been changed.
 190  *  ...
 191  *  bit  7: the status of port 6 has been changed.
 192  *  bit  8: the status of port 7 has been changed.
 193  *  ...
 194  *  bit 15: the status of port 14 has been changed.
 195  *
 196  * So, the maximum number of ports is 31 ( port 0 to port 30) ?
 197  *
 198  * The return value is the actual transfered length in byte. If nothing has
 199  * been changed, return 0. In the case that the number of ports is less than or
 200  * equal to 6 (VHCI_NPORTS==7), return 1.
 201  *
 202  */
 203 static int vhci_hub_status(struct usb_hcd *hcd, char *buf)
 204 {
 205         struct vhci_hcd *vhci;
 206         unsigned long   flags;
 207         int             retval = 0;
 208
 209         /* the enough buffer is allocated according to USB_MAXCHILDREN */
 210         unsigned long   *event_bits = (unsigned long *) buf;
 211         int             rhport;
 212         int             changed = 0;
 213
 214
 215         *event_bits = 0;
 216
 217         vhci = hcd_to_vhci(hcd);
 218
 219         spin_lock_irqsave(&vhci->lock, flags);
 220         if (!HCD_HW_ACCESSIBLE(hcd)) {
 221                 usbip_dbg_vhci_rh("hw accessible flag in on?\n");
 222                 goto done;
 223         }
 224
 225         /* check pseudo status register for each port */
 226         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 227                 if ((vhci->port_status[rhport] & PORT_C_MASK)) {
 228                         /* The status of a port has been changed, */
 229                         usbip_dbg_vhci_rh("port %d is changed\n", rhport);
 230
 231                         *event_bits |= 1 << (rhport + 1);
 232                         changed = 1;
 233                 }
 234         }
 235
 236         usbip_uinfo("changed %d\n", changed);
 237
 238         if (hcd->state == HC_STATE_SUSPENDED)
 239                 usb_hcd_resume_root_hub(hcd);
 240
 241         if (changed)
 242                 retval = 1 + (VHCI_NPORTS / 8);
 243         else
 244                 retval = 0;
 245
 246 done:
 247         spin_unlock_irqrestore(&vhci->lock, flags);
 248         return retval;
 249 }
 250
 251 /* See hub_configure in hub.c */
 252 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
 253 {
 254         memset(desc, 0, sizeof(*desc));
 255         desc->bDescriptorType = 0x29;
 256         desc->bDescLength = 9;
 257         desc->wHubCharacteristics = (__force __u16)
 258                 (__constant_cpu_to_le16(0x0001));
 259         desc->bNbrPorts = VHCI_NPORTS;
 260         desc->bitmap[0] = 0xff;
 261         desc->bitmap[1] = 0xff;
 262 }
 263
 264 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 265                             u16 wIndex, char *buf, u16 wLength)
 266 {
 267         struct vhci_hcd *dum;
 268         int             retval = 0;
 269         unsigned long   flags;
 270         int             rhport;
 271
 272         u32 prev_port_status[VHCI_NPORTS];
 273
 274         if (!HCD_HW_ACCESSIBLE(hcd))
 275                 return -ETIMEDOUT;
 276
 277         /*
 278          * NOTE:
 279          * wIndex shows the port number and begins from 1.
 280          */
 281         usbip_dbg_vhci_rh("typeReq %x wValue %x wIndex %x\n", typeReq, wValue,
 282                                                                 wIndex);
 283         if (wIndex > VHCI_NPORTS)
 284                 printk(KERN_ERR "%s: invalid port number %d\n", __func__,
 285                                                                 wIndex);
 286         rhport = ((__u8)(wIndex & 0x00ff)) - 1;
 287
 288         dum = hcd_to_vhci(hcd);
 289
 290         spin_lock_irqsave(&dum->lock, flags);
 291
 292         /* store old status and compare now and old later */
 293         if (usbip_dbg_flag_vhci_rh) {
 294                 int i = 0;
 295                 for (i = 0; i < VHCI_NPORTS; i++)
 296                         prev_port_status[i] = dum->port_status[i];
 297         }
 298
 299         switch (typeReq) {
 300         case ClearHubFeature:
 301                 usbip_dbg_vhci_rh(" ClearHubFeature\n");
 302                 break;
 303         case ClearPortFeature:
 304                 switch (wValue) {
 305                 case USB_PORT_FEAT_SUSPEND:
 306                         if (dum->port_status[rhport] & USB_PORT_STAT_SUSPEND) {
 307                                 /* 20msec signaling */
 308                                 dum->resuming = 1;
 309                                 dum->re_timeout =
 310                                         jiffies + msecs_to_jiffies(20);
 311                         }
 312                         break;
 313                 case USB_PORT_FEAT_POWER:
 314                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 315                                                 "USB_PORT_FEAT_POWER\n");
 316                         dum->port_status[rhport] = 0;
 317                         /* dum->address = 0; */
 318                         /* dum->hdev = 0; */
 319                         dum->resuming = 0;
 320                         break;
 321                 case USB_PORT_FEAT_C_RESET:
 322                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 323                                                 "USB_PORT_FEAT_C_RESET\n");
 324                         switch (dum->vdev[rhport].speed) {
 325                         case USB_SPEED_HIGH:
 326                                 dum->port_status[rhport] |=
 327                                                 USB_PORT_STAT_HIGH_SPEED;
 328                                 break;
 329                         case USB_SPEED_LOW:
 330                                 dum->port_status[rhport] |=
 331                                                 USB_PORT_STAT_LOW_SPEED;
 332                                 break;
 333                         default:
 334                                 break;
 335                         }
 336                 default:
 337                         usbip_dbg_vhci_rh(" ClearPortFeature: default %x\n",
 338                                                                 wValue);
 339                         dum->port_status[rhport] &= ~(1 << wValue);
 340                 }
 341                 break;
 342         case GetHubDescriptor:
 343                 usbip_dbg_vhci_rh(" GetHubDescriptor\n");
 344                 hub_descriptor((struct usb_hub_descriptor *) buf);
 345                 break;
 346         case GetHubStatus:
 347                 usbip_dbg_vhci_rh(" GetHubStatus\n");
 348                 *(__le32 *) buf = __constant_cpu_to_le32(0);
 349                 break;
 350         case GetPortStatus:
 351                 usbip_dbg_vhci_rh(" GetPortStatus port %x\n", wIndex);
 352                 if (wIndex > VHCI_NPORTS || wIndex < 1) {
 353                         printk(KERN_ERR "%s: invalid port number %d\n",
 354                                __func__, wIndex);
 355                         retval = -EPIPE;
 356                 }
 357
 358                 /* we do no care of resume. */
 359
 360                 /* whoever resets or resumes must GetPortStatus to
 361                  * complete it!!
 362                  *                                   */
 363                 if (dum->resuming && time_after(jiffies, dum->re_timeout)) {
 364                         printk(KERN_ERR "%s: not yet\n", __func__);
 365                         dum->port_status[rhport] |=
 366                                         (1 << USB_PORT_FEAT_C_SUSPEND);
 367                         dum->port_status[rhport] &=
 368                                         ~(1 << USB_PORT_FEAT_SUSPEND);
 369                         dum->resuming = 0;
 370                         dum->re_timeout = 0;
 371                         /* if (dum->driver && dum->driver->resume) {
 372                          *      spin_unlock (&dum->lock);
 373                          *      dum->driver->resume (&dum->gadget);
 374                          *      spin_lock (&dum->lock);
 375                          * } */
 376                 }
 377
 378                 if ((dum->port_status[rhport] & (1 << USB_PORT_FEAT_RESET)) !=
 379                                 0 && time_after(jiffies, dum->re_timeout)) {
 380                         dum->port_status[rhport] |=
 381                                                 (1 << USB_PORT_FEAT_C_RESET);
 382                         dum->port_status[rhport] &=
 383                                                 ~(1 << USB_PORT_FEAT_RESET);
 384                         dum->re_timeout = 0;
 385
 386                         if (dum->vdev[rhport].ud.status ==
 387                                                         VDEV_ST_NOTASSIGNED) {
 388                                 usbip_dbg_vhci_rh(" enable rhport %d "
 389                                                 "(status %u)\n",
 390                                                 rhport,
 391                                                 dum->vdev[rhport].ud.status);
 392                                 dum->port_status[rhport] |=
 393                                                         USB_PORT_STAT_ENABLE;
 394                         }
 395 #if 0
 396                         if (dum->driver) {
 397
 398                                 dum->port_status[rhport] |=
 399                                                         USB_PORT_STAT_ENABLE;
 400                                 /* give it the best speed we agree on */
 401                                 dum->gadget.speed = dum->driver->speed;
 402                                 dum->gadget.ep0->maxpacket = 64;
 403                                 switch (dum->gadget.speed) {
 404                                 case USB_SPEED_HIGH:
 405                                         dum->port_status[rhport] |=
 406                                         USB_PORT_STAT_HIGH_SPEED;
 407                                         break;
 408                                 case USB_SPEED_LOW:
 409                                         dum->gadget.ep0->maxpacket = 8;
 410                                         dum->port_status[rhport] |=
 411                                         USB_PORT_STAT_LOW_SPEED;
 412                                         break;
 413                                 default:
 414                                         dum->gadget.speed = USB_SPEED_FULL;
 415                                         break;
 416                                 }
 417                         }
 418 #endif
 419
 420                 }
 421                 ((u16 *) buf)[0] = cpu_to_le16(dum->port_status[rhport]);
 422                 ((u16 *) buf)[1] =
 423                                 cpu_to_le16(dum->port_status[rhport] >> 16);
 424
 425                 usbip_dbg_vhci_rh(" GetPortStatus bye %x %x\n", ((u16 *)buf)[0],
 426                                                         ((u16 *)buf)[1]);
 427                 break;
 428         case SetHubFeature:
 429                 usbip_dbg_vhci_rh(" SetHubFeature\n");
 430                 retval = -EPIPE;
 431                 break;
 432         case SetPortFeature:
 433                 switch (wValue) {
 434                 case USB_PORT_FEAT_SUSPEND:
 435                         usbip_dbg_vhci_rh(" SetPortFeature: "
 436                                         "USB_PORT_FEAT_SUSPEND\n");
 437                         printk(KERN_ERR "%s: not yet\n", __func__);
 438 #if 0
 439                         dum->port_status[rhport] |=
 440                                                 (1 << USB_PORT_FEAT_SUSPEND);
 441                         if (dum->driver->suspend) {
 442                                 spin_unlock(&dum->lock);
 443                                 dum->driver->suspend(&dum->gadget);
 444                                 spin_lock(&dum->lock);
 445                         }
 446 #endif
 447                         break;
 448                 case USB_PORT_FEAT_RESET:
 449                         usbip_dbg_vhci_rh(" SetPortFeature: "
 450                                                 "USB_PORT_FEAT_RESET\n");
 451                         /* if it's already running, disconnect first */
 452                         if (dum->port_status[rhport] & USB_PORT_STAT_ENABLE) {
 453                                 dum->port_status[rhport] &=
 454                                                 ~(USB_PORT_STAT_ENABLE |
 455                                                   USB_PORT_STAT_LOW_SPEED |
 456                                                   USB_PORT_STAT_HIGH_SPEED);
 457 #if 0
 458                                 if (dum->driver) {
 459                                         dev_dbg(hardware, "disconnect\n");
 460                                         stop_activity(dum, dum->driver);
 461                                 }
 462 #endif
 463
 464                                 /* FIXME test that code path! */
 465                         }
 466                         /* 50msec reset signaling */
 467                         dum->re_timeout = jiffies + msecs_to_jiffies(50);
 468
 469                         /* FALLTHROUGH */
 470                 default:
 471                         usbip_dbg_vhci_rh(" SetPortFeature: default %d\n",
 472                                                                 wValue);
 473                         dum->port_status[rhport] |= (1 << wValue);
 474                 }
 475                 break;
 476
 477         default:
 478                 printk(KERN_ERR "%s: default: no such request\n", __func__);
 479                 /* dev_dbg (hardware,
 480                  *              "hub control req%04x v%04x i%04x l%d\n",
 481                  *              typeReq, wValue, wIndex, wLength); */
 482
 483                 /* "protocol stall" on error */
 484                 retval = -EPIPE;
 485         }
 486
 487         if (usbip_dbg_flag_vhci_rh) {
 488                 printk(KERN_DEBUG "port %d\n", rhport);
 489                 dump_port_status(prev_port_status[rhport]);
 490                 dump_port_status(dum->port_status[rhport]);
 491         }
 492         usbip_dbg_vhci_rh(" bye\n");
 493
 494         spin_unlock_irqrestore(&dum->lock, flags);
 495
 496         return retval;
 497 }
 498
 499
 500
 501 /*----------------------------------------------------------------------*/
 502
 503 static struct vhci_device *get_vdev(struct usb_device *udev)
 504 {
 505         int i;
 506
 507         if (!udev)
 508                 return NULL;
 509
 510         for (i = 0; i < VHCI_NPORTS; i++)
 511                 if (the_controller->vdev[i].udev == udev)
 512                         return port_to_vdev(i);
 513
 514         return NULL;
 515 }
 516
 517 static void vhci_tx_urb(struct urb *urb)
 518 {
 519         struct vhci_device *vdev = get_vdev(urb->dev);
 520         struct vhci_priv *priv;
 521         unsigned long flag;
 522
 523         if (!vdev) {
 524                 err("could not get virtual device");
 525                 /* BUG(); */
 526                 return;
 527         }
 528
 529         priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
 530
 531         spin_lock_irqsave(&vdev->priv_lock, flag);
 532
 533         if (!priv) {
 534                 dev_err(&urb->dev->dev, "malloc vhci_priv\n");
 535                 spin_unlock_irqrestore(&vdev->priv_lock, flag);
 536                 usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 537                 return;
 538         }
 539
 540         priv->seqnum = atomic_inc_return(&the_controller->seqnum);
 541         if (priv->seqnum == 0xffff)
 542                 usbip_uinfo("seqnum max\n");
 543
 544         priv->vdev = vdev;
 545         priv->urb = urb;
 546
 547         urb->hcpriv = (void *) priv;
 548
 549
 550         list_add_tail(&priv->list, &vdev->priv_tx);
 551
 552         wake_up(&vdev->waitq_tx);
 553         spin_unlock_irqrestore(&vdev->priv_lock, flag);
 554 }
 555
 556 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 557                             gfp_t mem_flags)
 558 {
 559         struct device *dev = &urb->dev->dev;
 560         int ret = 0;
 561         unsigned long flags;
 562
 563         usbip_dbg_vhci_hc("enter, usb_hcd %p urb %p mem_flags %d\n",
 564                     hcd, urb, mem_flags);
 565
 566         /* patch to usb_sg_init() is in 2.5.60 */
 567         BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);
 568
 569         spin_lock_irqsave(&the_controller->lock, flags);
 570
 571         if (urb->status != -EINPROGRESS) {
 572                 dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
 573                 spin_unlock_irqrestore(&the_controller->lock, flags);
 574                 return urb->status;
 575         }
 576
 577         ret = usb_hcd_link_urb_to_ep(hcd, urb);
 578         if (ret)
 579                 goto no_need_unlink;
 580
 581         /*
 582          * The enumeration process is as follows;
 583          *
 584          *  1. Get_Descriptor request to DevAddrs(0) EndPoint(0)
 585          *     to get max packet length of default pipe
 586          *
 587          *  2. Set_Address request to DevAddr(0) EndPoint(0)
 588          *
 589          */
 590
 591         if (usb_pipedevice(urb->pipe) == 0) {
 592                 __u8 type = usb_pipetype(urb->pipe);
 593                 struct usb_ctrlrequest *ctrlreq =
 594                                 (struct usb_ctrlrequest *) urb->setup_packet;
 595                 struct vhci_device *vdev =
 596                                 port_to_vdev(the_controller->pending_port);
 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
 651         spin_unlock_irqrestore(&the_controller->lock, flags);
 652
 653         return 0;
 654
 655 no_need_xmit:
 656         usb_hcd_unlink_urb_from_ep(hcd, urb);
 657 no_need_unlink:
 658         spin_unlock_irqrestore(&the_controller->lock, flags);
 659
 660         usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
 661
 662         return ret;
 663 }
 664
 665 /*
 666  * vhci_rx gives back the urb after receiving the reply of the urb.  If an
 667  * unlink pdu is sent or not, vhci_rx receives a normal return pdu and gives
 668  * back its urb. For the driver unlinking the urb, the content of the urb is
 669  * not important, but the calling to its completion handler is important; the
 670  * completion of unlinking is notified by the completion handler.
 671  *
 672  *
 673  * CLIENT SIDE
 674  *
 675  * - When vhci_hcd receives RET_SUBMIT,
 676  *
 677  *      - case 1a). the urb of the pdu is not unlinking.
 678  *              - normal case
 679  *              => just give back the urb
 680  *
 681  *      - case 1b). the urb of the pdu is unlinking.
 682  *              - usbip.ko will return a reply of the unlinking request.
 683  *              => give back the urb now and go to case 2b).
 684  *
 685  * - When vhci_hcd receives RET_UNLINK,
 686  *
 687  *      - case 2a). a submit request is still pending in vhci_hcd.
 688  *              - urb was really pending in usbip.ko and urb_unlink_urb() was
 689  *                completed there.
 690  *              => free a pending submit request
 691  *              => notify unlink completeness by giving back the urb
 692  *
 693  *      - case 2b). a submit request is *not* pending in vhci_hcd.
 694  *              - urb was already given back to the core driver.
 695  *              => do not give back the urb
 696  *
 697  *
 698  * SERVER SIDE
 699  *
 700  * - When usbip receives CMD_UNLINK,
 701  *
 702  *      - case 3a). the urb of the unlink request is now in submission.
 703  *              => do usb_unlink_urb().
 704  *              => after the unlink is completed, send RET_UNLINK.
 705  *
 706  *      - case 3b). the urb of the unlink request is not in submission.
 707  *              - may be already completed or never be received
 708  *              => send RET_UNLINK
 709  *
 710  */
 711 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 712 {
 713         unsigned long flags;
 714         struct vhci_priv *priv;
 715         struct vhci_device *vdev;
 716
 717         usbip_uinfo("vhci_hcd: dequeue a urb %p\n", urb);
 718
 719
 720         spin_lock_irqsave(&the_controller->lock, flags);
 721
 722         priv = urb->hcpriv;
 723         if (!priv) {
 724                 /* URB was never linked! or will be soon given back by
 725                  * vhci_rx. */
 726                 spin_unlock_irqrestore(&the_controller->lock, flags);
 727                 return 0;
 728         }
 729
 730         {
 731                 int ret = 0;
 732                 ret = usb_hcd_check_unlink_urb(hcd, urb, status);
 733                 if (ret) {
 734                         spin_unlock_irqrestore(&the_controller->lock, flags);
 735                         return ret;
 736                 }
 737         }
 738
 739          /* send unlink request here? */
 740         vdev = priv->vdev;
 741
 742         if (!vdev->ud.tcp_socket) {
 743                 /* tcp connection is closed */
 744                 unsigned long flags2;
 745
 746                 spin_lock_irqsave(&vdev->priv_lock, flags2);
 747
 748                 usbip_uinfo("vhci_hcd: device %p seems to be disconnected\n",
 749                                                                         vdev);
 750                 list_del(&priv->list);
 751                 kfree(priv);
 752                 urb->hcpriv = NULL;
 753
 754                 spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 755
 756                 /*
 757                  * If tcp connection is alive, we have sent CMD_UNLINK.
 758                  * vhci_rx will receive RET_UNLINK and give back the URB.
 759                  * Otherwise, we give back it here.
 760                  */
 761                 usbip_uinfo("vhci_hcd: vhci_urb_dequeue() gives back urb %p\n",
 762                                                                         urb);
 763
 764                 usb_hcd_unlink_urb_from_ep(hcd, urb);
 765
 766                 spin_unlock_irqrestore(&the_controller->lock, flags);
 767                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 768                                                                 urb->status);
 769                 spin_lock_irqsave(&the_controller->lock, flags);
 770
 771         } else {
 772                 /* tcp connection is alive */
 773                 unsigned long flags2;
 774                 struct vhci_unlink *unlink;
 775
 776                 spin_lock_irqsave(&vdev->priv_lock, flags2);
 777
 778                 /* setup CMD_UNLINK pdu */
 779                 unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
 780                 if (!unlink) {
 781                         usbip_uerr("malloc vhci_unlink\n");
 782                         spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 783                         spin_unlock_irqrestore(&the_controller->lock, flags);
 784                         usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 785                         return -ENOMEM;
 786                 }
 787
 788                 unlink->seqnum = atomic_inc_return(&the_controller->seqnum);
 789                 if (unlink->seqnum == 0xffff)
 790                         usbip_uinfo("seqnum max\n");
 791
 792                 unlink->unlink_seqnum = priv->seqnum;
 793
 794                 usbip_uinfo("vhci_hcd: device %p seems to be still connected\n",
 795                                                                         vdev);
 796
 797                 /* send cmd_unlink and try to cancel the pending URB in the
 798                  * peer */
 799                 list_add_tail(&unlink->list, &vdev->unlink_tx);
 800                 wake_up(&vdev->waitq_tx);
 801
 802                 spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 803         }
 804
 805         spin_unlock_irqrestore(&the_controller->lock, flags);
 806
 807         usbip_dbg_vhci_hc("leave\n");
 808         return 0;
 809 }
 810
 811
 812 static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
 813 {
 814         struct vhci_unlink *unlink, *tmp;
 815
 816         spin_lock(&vdev->priv_lock);
 817
 818         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
 819                 list_del(&unlink->list);
 820                 kfree(unlink);
 821         }
 822
 823         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
 824                 list_del(&unlink->list);
 825                 kfree(unlink);
 826         }
 827
 828         spin_unlock(&vdev->priv_lock);
 829 }
 830
 831 /*
 832  * The important thing is that only one context begins cleanup.
 833  * This is why error handling and cleanup become simple.
 834  * We do not want to consider race condition as possible.
 835  */
 836 static void vhci_shutdown_connection(struct usbip_device *ud)
 837 {
 838         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 839
 840         /* need this? see stub_dev.c */
 841         if (ud->tcp_socket) {
 842                 usbip_udbg("shutdown tcp_socket %p\n", ud->tcp_socket);
 843                 kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
 844         }
 845
 846         usbip_stop_threads(&vdev->ud);
 847         usbip_uinfo("stop threads\n");
 848
 849         /* active connection is closed */
 850         if (vdev->ud.tcp_socket != NULL) {
 851                 sock_release(vdev->ud.tcp_socket);
 852                 vdev->ud.tcp_socket = NULL;
 853         }
 854         usbip_uinfo("release socket\n");
 855
 856         vhci_device_unlink_cleanup(vdev);
 857
 858         /*
 859          * rh_port_disconnect() is a trigger of ...
 860          *   usb_disable_device():
 861          *      disable all the endpoints for a USB device.
 862          *   usb_disable_endpoint():
 863          *      disable endpoints. pending urbs are unlinked(dequeued).
 864          *
 865          * NOTE: After calling rh_port_disconnect(), the USB device drivers of a
 866          * deteched device should release used urbs in a cleanup function(i.e.
 867          * xxx_disconnect()). Therefore, vhci_hcd does not need to release
 868          * pushed urbs and their private data in this function.
 869          *
 870          * NOTE: vhci_dequeue() must be considered carefully. When shutdowning
 871          * a connection, vhci_shutdown_connection() expects vhci_dequeue()
 872          * gives back pushed urbs and frees their private data by request of
 873          * the cleanup function of a USB driver. When unlinking a urb with an
 874          * active connection, vhci_dequeue() does not give back the urb which
 875          * is actually given back by vhci_rx after receiving its return pdu.
 876          *
 877          */
 878         rh_port_disconnect(vdev->rhport);
 879
 880         usbip_uinfo("disconnect device\n");
 881 }
 882
 883
 884 static void vhci_device_reset(struct usbip_device *ud)
 885 {
 886         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 887
 888         spin_lock(&ud->lock);
 889
 890         vdev->speed  = 0;
 891         vdev->devid  = 0;
 892
 893         if (vdev->udev)
 894                 usb_put_dev(vdev->udev);
 895         vdev->udev = NULL;
 896
 897         ud->tcp_socket = NULL;
 898
 899         ud->status = VDEV_ST_NULL;
 900
 901         spin_unlock(&ud->lock);
 902 }
 903
 904 static void vhci_device_unusable(struct usbip_device *ud)
 905 {
 906         spin_lock(&ud->lock);
 907
 908         ud->status = VDEV_ST_ERROR;
 909
 910         spin_unlock(&ud->lock);
 911 }
 912
 913 static void vhci_device_init(struct vhci_device *vdev)
 914 {
 915         memset(vdev, 0, sizeof(*vdev));
 916
 917         usbip_task_init(&vdev->ud.tcp_rx, "vhci_rx", vhci_rx_loop);
 918         usbip_task_init(&vdev->ud.tcp_tx, "vhci_tx", vhci_tx_loop);
 919
 920         vdev->ud.side   = USBIP_VHCI;
 921         vdev->ud.status = VDEV_ST_NULL;
 922         /* vdev->ud.lock   = SPIN_LOCK_UNLOCKED; */
 923         spin_lock_init(&vdev->ud.lock);
 924
 925         INIT_LIST_HEAD(&vdev->priv_rx);
 926         INIT_LIST_HEAD(&vdev->priv_tx);
 927         INIT_LIST_HEAD(&vdev->unlink_tx);
 928         INIT_LIST_HEAD(&vdev->unlink_rx);
 929         /* vdev->priv_lock = SPIN_LOCK_UNLOCKED; */
 930         spin_lock_init(&vdev->priv_lock);
 931
 932         init_waitqueue_head(&vdev->waitq_tx);
 933
 934         vdev->ud.eh_ops.shutdown = vhci_shutdown_connection;
 935         vdev->ud.eh_ops.reset = vhci_device_reset;
 936         vdev->ud.eh_ops.unusable = vhci_device_unusable;
 937
 938         usbip_start_eh(&vdev->ud);
 939 }
 940
 941
 942 /*----------------------------------------------------------------------*/
 943
 944 static int vhci_start(struct usb_hcd *hcd)
 945 {
 946         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 947         int rhport;
 948         int err = 0;
 949
 950         usbip_dbg_vhci_hc("enter vhci_start\n");
 951
 952
 953         /* initialize private data of usb_hcd */
 954
 955         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 956                 struct vhci_device *vdev = &vhci->vdev[rhport];
 957                 vhci_device_init(vdev);
 958                 vdev->rhport = rhport;
 959         }
 960
 961         atomic_set(&vhci->seqnum, 0);
 962         spin_lock_init(&vhci->lock);
 963
 964
 965
 966         hcd->power_budget = 0; /* no limit */
 967         hcd->state  = HC_STATE_RUNNING;
 968         hcd->uses_new_polling = 1;
 969
 970
 971         /* vhci_hcd is now ready to be controlled through sysfs */
 972         err = sysfs_create_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 973         if (err) {
 974                 usbip_uerr("create sysfs files\n");
 975                 return err;
 976         }
 977
 978         return 0;
 979 }
 980
 981 static void vhci_stop(struct usb_hcd *hcd)
 982 {
 983         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 984         int rhport = 0;
 985
 986         usbip_dbg_vhci_hc("stop VHCI controller\n");
 987
 988
 989         /* 1. remove the userland interface of vhci_hcd */
 990         sysfs_remove_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 991
 992         /* 2. shutdown all the ports of vhci_hcd */
 993         for (rhport = 0 ; rhport < VHCI_NPORTS; rhport++) {
 994                 struct vhci_device *vdev = &vhci->vdev[rhport];
 995
 996                 usbip_event_add(&vdev->ud, VDEV_EVENT_REMOVED);
 997                 usbip_stop_eh(&vdev->ud);
 998         }
 999
1000
1001         usbip_uinfo("vhci_stop done\n");
1002 }
1003
1004 /*----------------------------------------------------------------------*/
1005
1006 static int vhci_get_frame_number(struct usb_hcd *hcd)
1007 {
1008         usbip_uerr("Not yet implemented\n");
1009         return 0;
1010 }
1011
1012
1013 #ifdef CONFIG_PM
1014
1015 /* FIXME: suspend/resume */
1016 static int vhci_bus_suspend(struct usb_hcd *hcd)
1017 {
1018         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
1019
1020         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1021
1022         spin_lock_irq(&vhci->lock);
1023         /* vhci->rh_state = DUMMY_RH_SUSPENDED;
1024          * set_link_state(vhci); */
1025         hcd->state = HC_STATE_SUSPENDED;
1026         spin_unlock_irq(&vhci->lock);
1027
1028         return 0;
1029 }
1030
1031 static int vhci_bus_resume(struct usb_hcd *hcd)
1032 {
1033         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
1034         int rc = 0;
1035
1036         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1037
1038         spin_lock_irq(&vhci->lock);
1039         if (!HCD_HW_ACCESSIBLE(hcd)) {
1040                 rc = -ESHUTDOWN;
1041         } else {
1042                 /* vhci->rh_state = DUMMY_RH_RUNNING;
1043                  * set_link_state(vhci);
1044                  * if (!list_empty(&vhci->urbp_list))
1045                  *      mod_timer(&vhci->timer, jiffies); */
1046                 hcd->state = HC_STATE_RUNNING;
1047         }
1048         spin_unlock_irq(&vhci->lock);
1049         return rc;
1050
1051         return 0;
1052 }
1053
1054 #else
1055
1056 #define vhci_bus_suspend      NULL
1057 #define vhci_bus_resume       NULL
1058 #endif
1059
1060
1061
1062 static struct hc_driver vhci_hc_driver = {
1063         .description    = driver_name,
1064         .product_desc   = driver_desc,
1065         .hcd_priv_size  = sizeof(struct vhci_hcd),
1066
1067         .flags          = HCD_USB2,
1068
1069         .start          = vhci_start,
1070         .stop           = vhci_stop,
1071
1072         .urb_enqueue    = vhci_urb_enqueue,
1073         .urb_dequeue    = vhci_urb_dequeue,
1074
1075         .get_frame_number = vhci_get_frame_number,
1076
1077         .hub_status_data = vhci_hub_status,
1078         .hub_control    = vhci_hub_control,
1079         .bus_suspend    = vhci_bus_suspend,
1080         .bus_resume     = vhci_bus_resume,
1081 };
1082
1083 static int vhci_hcd_probe(struct platform_device *pdev)
1084 {
1085         struct usb_hcd          *hcd;
1086         int                     ret;
1087
1088         usbip_uinfo("proving...\n");
1089
1090         usbip_dbg_vhci_hc("name %s id %d\n", pdev->name, pdev->id);
1091
1092         /* will be removed */
1093         if (pdev->dev.dma_mask) {
1094                 dev_info(&pdev->dev, "vhci_hcd DMA not supported\n");
1095                 return -EINVAL;
1096         }
1097
1098         /*
1099          * Allocate and initialize hcd.
1100          * Our private data is also allocated automatically.
1101          */
1102         hcd = usb_create_hcd(&vhci_hc_driver, &pdev->dev, dev_name(&pdev->dev));
1103         if (!hcd) {
1104                 usbip_uerr("create hcd failed\n");
1105                 return -ENOMEM;
1106         }
1107
1108
1109         /* this is private data for vhci_hcd */
1110         the_controller = hcd_to_vhci(hcd);
1111
1112         /*
1113          * Finish generic HCD structure initialization and register.
1114          * Call the driver's reset() and start() routines.
1115          */
1116         ret = usb_add_hcd(hcd, 0, 0);
1117         if (ret != 0) {
1118                 usbip_uerr("usb_add_hcd failed %d\n", ret);
1119                 usb_put_hcd(hcd);
1120                 the_controller = NULL;
1121                 return ret;
1122         }
1123
1124
1125         usbip_dbg_vhci_hc("bye\n");
1126         return 0;
1127 }
1128
1129
1130 static int vhci_hcd_remove(struct platform_device *pdev)
1131 {
1132         struct usb_hcd  *hcd;
1133
1134         hcd = platform_get_drvdata(pdev);
1135         if (!hcd)
1136                 return 0;
1137
1138         /*
1139          * Disconnects the root hub,
1140          * then reverses the effects of usb_add_hcd(),
1141          * invoking the HCD's stop() methods.
1142          */
1143         usb_remove_hcd(hcd);
1144         usb_put_hcd(hcd);
1145         the_controller = NULL;
1146
1147
1148         return 0;
1149 }
1150
1151
1152
1153 #ifdef CONFIG_PM
1154
1155 /* what should happen for USB/IP under suspend/resume? */
1156 static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
1157 {
1158         struct usb_hcd *hcd;
1159         int rhport = 0;
1160         int connected = 0;
1161         int ret = 0;
1162
1163         dev_dbg(&pdev->dev, "%s\n", __func__);
1164
1165         hcd = platform_get_drvdata(pdev);
1166
1167         spin_lock(&the_controller->lock);
1168
1169         for (rhport = 0; rhport < VHCI_NPORTS; rhport++)
1170                 if (the_controller->port_status[rhport] &
1171                                                 USB_PORT_STAT_CONNECTION)
1172                         connected += 1;
1173
1174         spin_unlock(&the_controller->lock);
1175
1176         if (connected > 0) {
1177                 usbip_uinfo("We have %d active connection%s. Do not suspend.\n",
1178                                 connected, (connected == 1 ? "" : "s"));
1179                 ret =  -EBUSY;
1180         } else {
1181                 usbip_uinfo("suspend vhci_hcd");
1182                 clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1183         }
1184
1185         return ret;
1186 }
1187
1188 static int vhci_hcd_resume(struct platform_device *pdev)
1189 {
1190         struct usb_hcd *hcd;
1191
1192         dev_dbg(&pdev->dev, "%s\n", __func__);
1193
1194         hcd = platform_get_drvdata(pdev);
1195         set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1196         usb_hcd_poll_rh_status(hcd);
1197
1198         return 0;
1199 }
1200
1201 #else
1202
1203 #define vhci_hcd_suspend        NULL
1204 #define vhci_hcd_resume         NULL
1205
1206 #endif
1207
1208
1209 static struct platform_driver vhci_driver = {
1210         .probe  = vhci_hcd_probe,
1211         .remove = __devexit_p(vhci_hcd_remove),
1212         .suspend = vhci_hcd_suspend,
1213         .resume = vhci_hcd_resume,
1214         .driver = {
1215                 .name = (char *) driver_name,
1216                 .owner = THIS_MODULE,
1217         },
1218 };
1219
1220 /*----------------------------------------------------------------------*/
1221
1222 /*
1223  * The VHCI 'device' is 'virtual'; not a real plug&play hardware.
1224  * We need to add this virtual device as a platform device arbitrarily:
1225  *      1. platform_device_register()
1226  */
1227 static void the_pdev_release(struct device *dev)
1228 {
1229         return;
1230 }
1231
1232 static struct platform_device the_pdev = {
1233         /* should be the same name as driver_name */
1234         .name = (char *) driver_name,
1235         .id = -1,
1236         .dev = {
1237                 /* .driver = &vhci_driver, */
1238                 .release = the_pdev_release,
1239         },
1240 };
1241
1242 static int __init vhci_init(void)
1243 {
1244         int ret;
1245
1246         usbip_dbg_vhci_hc("enter\n");
1247         if (usb_disabled())
1248                 return -ENODEV;
1249
1250         printk(KERN_INFO KBUILD_MODNAME ": %s, %s\n", driver_name,
1251                DRIVER_VERSION);
1252
1253         ret = platform_driver_register(&vhci_driver);
1254         if (ret < 0)
1255                 goto err_driver_register;
1256
1257         ret = platform_device_register(&the_pdev);
1258         if (ret < 0)
1259                 goto err_platform_device_register;
1260
1261         usbip_dbg_vhci_hc("bye\n");
1262         return ret;
1263
1264         /* error occurred */
1265 err_platform_device_register:
1266         platform_driver_unregister(&vhci_driver);
1267
1268 err_driver_register:
1269         usbip_dbg_vhci_hc("bye\n");
1270         return ret;
1271 }
1272 module_init(vhci_init);
1273
1274 static void __exit vhci_cleanup(void)
1275 {
1276         usbip_dbg_vhci_hc("enter\n");
1277
1278         platform_device_unregister(&the_pdev);
1279         platform_driver_unregister(&vhci_driver);
1280
1281         usbip_dbg_vhci_hc("bye\n");
1282 }
1283 module_exit(vhci_cleanup);