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
 169
 170
 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 transfered 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
 213         *event_bits = 0;
 214
 215         vhci = hcd_to_vhci(hcd);
 216
 217         spin_lock_irqsave(&vhci->lock, flags);
 218         if (!HCD_HW_ACCESSIBLE(hcd)) {
 219                 usbip_dbg_vhci_rh("hw accessible flag in on?\n");
 220                 goto done;
 221         }
 222
 223         /* check pseudo status register for each port */
 224         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 225                 if ((vhci->port_status[rhport] & PORT_C_MASK)) {
 226                         /* The status of a port has been changed, */
 227                         usbip_dbg_vhci_rh("port %d is changed\n", rhport);
 228
 229                         *event_bits |= 1 << (rhport + 1);
 230                         changed = 1;
 231                 }
 232         }
 233
 234         usbip_uinfo("changed %d\n", changed);
 235
 236         if (hcd->state == HC_STATE_SUSPENDED)
 237                 usb_hcd_resume_root_hub(hcd);
 238
 239         if (changed)
 240                 retval = 1 + (VHCI_NPORTS / 8);
 241         else
 242                 retval = 0;
 243
 244 done:
 245         spin_unlock_irqrestore(&vhci->lock, flags);
 246         return retval;
 247 }
 248
 249 /* See hub_configure in hub.c */
 250 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
 251 {
 252         memset(desc, 0, sizeof(*desc));
 253         desc->bDescriptorType = 0x29;
 254         desc->bDescLength = 9;
 255         desc->wHubCharacteristics = (__force __u16)
 256                 (__constant_cpu_to_le16(0x0001));
 257         desc->bNbrPorts = VHCI_NPORTS;
 258         desc->bitmap[0] = 0xff;
 259         desc->bitmap[1] = 0xff;
 260 }
 261
 262 static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 263                             u16 wIndex, char *buf, u16 wLength)
 264 {
 265         struct vhci_hcd *dum;
 266         int             retval = 0;
 267         unsigned long   flags;
 268         int             rhport;
 269
 270         u32 prev_port_status[VHCI_NPORTS];
 271
 272         if (!HCD_HW_ACCESSIBLE(hcd))
 273                 return -ETIMEDOUT;
 274
 275         /*
 276          * NOTE:
 277          * wIndex shows the port number and begins from 1.
 278          */
 279         usbip_dbg_vhci_rh("typeReq %x wValue %x wIndex %x\n", typeReq, wValue,
 280                                                                 wIndex);
 281         if (wIndex > VHCI_NPORTS)
 282                 printk(KERN_ERR "%s: invalid port number %d\n", __func__,
 283                                                                 wIndex);
 284         rhport = ((__u8)(wIndex & 0x00ff)) - 1;
 285
 286         dum = hcd_to_vhci(hcd);
 287
 288         spin_lock_irqsave(&dum->lock, flags);
 289
 290         /* store old status and compare now and old later */
 291         if (usbip_dbg_flag_vhci_rh) {
 292                 int i = 0;
 293                 for (i = 0; i < VHCI_NPORTS; i++)
 294                         prev_port_status[i] = dum->port_status[i];
 295         }
 296
 297         switch (typeReq) {
 298         case ClearHubFeature:
 299                 usbip_dbg_vhci_rh(" ClearHubFeature\n");
 300                 break;
 301         case ClearPortFeature:
 302                 switch (wValue) {
 303                 case USB_PORT_FEAT_SUSPEND:
 304                         if (dum->port_status[rhport] & USB_PORT_STAT_SUSPEND) {
 305                                 /* 20msec signaling */
 306                                 dum->resuming = 1;
 307                                 dum->re_timeout =
 308                                         jiffies + msecs_to_jiffies(20);
 309                         }
 310                         break;
 311                 case USB_PORT_FEAT_POWER:
 312                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 313                                                 "USB_PORT_FEAT_POWER\n");
 314                         dum->port_status[rhport] = 0;
 315                         /* dum->address = 0; */
 316                         /* dum->hdev = 0; */
 317                         dum->resuming = 0;
 318                         break;
 319                 case USB_PORT_FEAT_C_RESET:
 320                         usbip_dbg_vhci_rh(" ClearPortFeature: "
 321                                                 "USB_PORT_FEAT_C_RESET\n");
 322                         switch (dum->vdev[rhport].speed) {
 323                         case USB_SPEED_HIGH:
 324                                 dum->port_status[rhport] |=
 325                                                 USB_PORT_STAT_HIGH_SPEED;
 326                                 break;
 327                         case USB_SPEED_LOW:
 328                                 dum->port_status[rhport] |=
 329                                                 USB_PORT_STAT_LOW_SPEED;
 330                                 break;
 331                         default:
 332                                 break;
 333                         }
 334                 default:
 335                         usbip_dbg_vhci_rh(" ClearPortFeature: default %x\n",
 336                                                                 wValue);
 337                         dum->port_status[rhport] &= ~(1 << wValue);
 338                 }
 339                 break;
 340         case GetHubDescriptor:
 341                 usbip_dbg_vhci_rh(" GetHubDescriptor\n");
 342                 hub_descriptor((struct usb_hub_descriptor *) buf);
 343                 break;
 344         case GetHubStatus:
 345                 usbip_dbg_vhci_rh(" GetHubStatus\n");
 346                 *(__le32 *) buf = __constant_cpu_to_le32(0);
 347                 break;
 348         case GetPortStatus:
 349                 usbip_dbg_vhci_rh(" GetPortStatus port %x\n", wIndex);
 350                 if (wIndex > VHCI_NPORTS || wIndex < 1) {
 351                         printk(KERN_ERR "%s: invalid port number %d\n",
 352                                __func__, wIndex);
 353                         retval = -EPIPE;
 354                 }
 355
 356                 /* we do no care of resume. */
 357
 358                 /* whoever resets or resumes must GetPortStatus to
 359                  * complete it!!
 360                  *                                   */
 361                 if (dum->resuming && time_after(jiffies, dum->re_timeout)) {
 362                         printk(KERN_ERR "%s: not yet\n", __func__);
 363                         dum->port_status[rhport] |=
 364                                         (1 << USB_PORT_FEAT_C_SUSPEND);
 365                         dum->port_status[rhport] &=
 366                                         ~(1 << USB_PORT_FEAT_SUSPEND);
 367                         dum->resuming = 0;
 368                         dum->re_timeout = 0;
 369                         /* if (dum->driver && dum->driver->resume) {
 370                          *      spin_unlock (&dum->lock);
 371                          *      dum->driver->resume (&dum->gadget);
 372                          *      spin_lock (&dum->lock);
 373                          * } */
 374                 }
 375
 376                 if ((dum->port_status[rhport] & (1 << USB_PORT_FEAT_RESET)) !=
 377                                 0 && time_after(jiffies, dum->re_timeout)) {
 378                         dum->port_status[rhport] |=
 379                                                 (1 << USB_PORT_FEAT_C_RESET);
 380                         dum->port_status[rhport] &=
 381                                                 ~(1 << USB_PORT_FEAT_RESET);
 382                         dum->re_timeout = 0;
 383
 384                         if (dum->vdev[rhport].ud.status ==
 385                                                         VDEV_ST_NOTASSIGNED) {
 386                                 usbip_dbg_vhci_rh(" enable rhport %d "
 387                                                 "(status %u)\n",
 388                                                 rhport,
 389                                                 dum->vdev[rhport].ud.status);
 390                                 dum->port_status[rhport] |=
 391                                                         USB_PORT_STAT_ENABLE;
 392                         }
 393 #if 0
 394                         if (dum->driver) {
 395
 396                                 dum->port_status[rhport] |=
 397                                                         USB_PORT_STAT_ENABLE;
 398                                 /* give it the best speed we agree on */
 399                                 dum->gadget.speed = dum->driver->speed;
 400                                 dum->gadget.ep0->maxpacket = 64;
 401                                 switch (dum->gadget.speed) {
 402                                 case USB_SPEED_HIGH:
 403                                         dum->port_status[rhport] |=
 404                                         USB_PORT_STAT_HIGH_SPEED;
 405                                         break;
 406                                 case USB_SPEED_LOW:
 407                                         dum->gadget.ep0->maxpacket = 8;
 408                                         dum->port_status[rhport] |=
 409                                         USB_PORT_STAT_LOW_SPEED;
 410                                         break;
 411                                 default:
 412                                         dum->gadget.speed = USB_SPEED_FULL;
 413                                         break;
 414                                 }
 415                         }
 416 #endif
 417
 418                 }
 419                 ((u16 *) buf)[0] = cpu_to_le16(dum->port_status[rhport]);
 420                 ((u16 *) buf)[1] =
 421                                 cpu_to_le16(dum->port_status[rhport] >> 16);
 422
 423                 usbip_dbg_vhci_rh(" GetPortStatus bye %x %x\n", ((u16 *)buf)[0],
 424                                                         ((u16 *)buf)[1]);
 425                 break;
 426         case SetHubFeature:
 427                 usbip_dbg_vhci_rh(" SetHubFeature\n");
 428                 retval = -EPIPE;
 429                 break;
 430         case SetPortFeature:
 431                 switch (wValue) {
 432                 case USB_PORT_FEAT_SUSPEND:
 433                         usbip_dbg_vhci_rh(" SetPortFeature: "
 434                                         "USB_PORT_FEAT_SUSPEND\n");
 435                         printk(KERN_ERR "%s: not yet\n", __func__);
 436 #if 0
 437                         dum->port_status[rhport] |=
 438                                                 (1 << USB_PORT_FEAT_SUSPEND);
 439                         if (dum->driver->suspend) {
 440                                 spin_unlock(&dum->lock);
 441                                 dum->driver->suspend(&dum->gadget);
 442                                 spin_lock(&dum->lock);
 443                         }
 444 #endif
 445                         break;
 446                 case USB_PORT_FEAT_RESET:
 447                         usbip_dbg_vhci_rh(" SetPortFeature: "
 448                                                 "USB_PORT_FEAT_RESET\n");
 449                         /* if it's already running, disconnect first */
 450                         if (dum->port_status[rhport] & USB_PORT_STAT_ENABLE) {
 451                                 dum->port_status[rhport] &=
 452                                                 ~(USB_PORT_STAT_ENABLE |
 453                                                   USB_PORT_STAT_LOW_SPEED |
 454                                                   USB_PORT_STAT_HIGH_SPEED);
 455 #if 0
 456                                 if (dum->driver) {
 457                                         dev_dbg(hardware, "disconnect\n");
 458                                         stop_activity(dum, dum->driver);
 459                                 }
 460 #endif
 461
 462                                 /* FIXME test that code path! */
 463                         }
 464                         /* 50msec reset signaling */
 465                         dum->re_timeout = jiffies + msecs_to_jiffies(50);
 466
 467                         /* FALLTHROUGH */
 468                 default:
 469                         usbip_dbg_vhci_rh(" SetPortFeature: default %d\n",
 470                                                                 wValue);
 471                         dum->port_status[rhport] |= (1 << wValue);
 472                 }
 473                 break;
 474
 475         default:
 476                 printk(KERN_ERR "%s: default: no such request\n", __func__);
 477                 /* dev_dbg (hardware,
 478                  *              "hub control req%04x v%04x i%04x l%d\n",
 479                  *              typeReq, wValue, wIndex, wLength); */
 480
 481                 /* "protocol stall" on error */
 482                 retval = -EPIPE;
 483         }
 484
 485         if (usbip_dbg_flag_vhci_rh) {
 486                 printk(KERN_DEBUG "port %d\n", rhport);
 487                 dump_port_status(prev_port_status[rhport]);
 488                 dump_port_status(dum->port_status[rhport]);
 489         }
 490         usbip_dbg_vhci_rh(" bye\n");
 491
 492         spin_unlock_irqrestore(&dum->lock, flags);
 493
 494         return retval;
 495 }
 496
 497
 498
 499 /*----------------------------------------------------------------------*/
 500
 501 static struct vhci_device *get_vdev(struct usb_device *udev)
 502 {
 503         int i;
 504
 505         if (!udev)
 506                 return NULL;
 507
 508         for (i = 0; i < VHCI_NPORTS; i++)
 509                 if (the_controller->vdev[i].udev == udev)
 510                         return port_to_vdev(i);
 511
 512         return NULL;
 513 }
 514
 515 static void vhci_tx_urb(struct urb *urb)
 516 {
 517         struct vhci_device *vdev = get_vdev(urb->dev);
 518         struct vhci_priv *priv;
 519         unsigned long flag;
 520
 521         if (!vdev) {
 522                 err("could not get virtual device");
 523                 /* BUG(); */
 524                 return;
 525         }
 526
 527         priv = kzalloc(sizeof(struct vhci_priv), GFP_ATOMIC);
 528
 529         spin_lock_irqsave(&vdev->priv_lock, flag);
 530
 531         if (!priv) {
 532                 dev_err(&urb->dev->dev, "malloc vhci_priv\n");
 533                 spin_unlock_irqrestore(&vdev->priv_lock, flag);
 534                 usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 535                 return;
 536         }
 537
 538         priv->seqnum = atomic_inc_return(&the_controller->seqnum);
 539         if (priv->seqnum == 0xffff)
 540                 usbip_uinfo("seqnum max\n");
 541
 542         priv->vdev = vdev;
 543         priv->urb = urb;
 544
 545         urb->hcpriv = (void *) priv;
 546
 547
 548         list_add_tail(&priv->list, &vdev->priv_tx);
 549
 550         wake_up(&vdev->waitq_tx);
 551         spin_unlock_irqrestore(&vdev->priv_lock, flag);
 552 }
 553
 554 static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
 555                             gfp_t mem_flags)
 556 {
 557         struct device *dev = &urb->dev->dev;
 558         int ret = 0;
 559         unsigned long flags;
 560
 561         usbip_dbg_vhci_hc("enter, usb_hcd %p urb %p mem_flags %d\n",
 562                     hcd, urb, mem_flags);
 563
 564         /* patch to usb_sg_init() is in 2.5.60 */
 565         BUG_ON(!urb->transfer_buffer && urb->transfer_buffer_length);
 566
 567         spin_lock_irqsave(&the_controller->lock, flags);
 568
 569         if (urb->status != -EINPROGRESS) {
 570                 dev_err(dev, "URB already unlinked!, status %d\n", urb->status);
 571                 spin_unlock_irqrestore(&the_controller->lock, flags);
 572                 return urb->status;
 573         }
 574
 575         ret = usb_hcd_link_urb_to_ep(hcd, urb);
 576         if (ret)
 577                 goto no_need_unlink;
 578
 579         /*
 580          * The enumeration process is as follows;
 581          *
 582          *  1. Get_Descriptor request to DevAddrs(0) EndPoint(0)
 583          *     to get max packet length of default pipe
 584          *
 585          *  2. Set_Address request to DevAddr(0) EndPoint(0)
 586          *
 587          */
 588
 589         if (usb_pipedevice(urb->pipe) == 0) {
 590                 __u8 type = usb_pipetype(urb->pipe);
 591                 struct usb_ctrlrequest *ctrlreq =
 592                                 (struct usb_ctrlrequest *) urb->setup_packet;
 593                 struct vhci_device *vdev =
 594                                 port_to_vdev(the_controller->pending_port);
 595
 596                 if (type != PIPE_CONTROL || !ctrlreq) {
 597                         dev_err(dev, "invalid request to devnum 0\n");
 598                         ret = -EINVAL;
 599                         goto no_need_xmit;
 600                 }
 601
 602                 switch (ctrlreq->bRequest) {
 603                 case USB_REQ_SET_ADDRESS:
 604                         /* set_address may come when a device is reset */
 605                         dev_info(dev, "SetAddress Request (%d) to port %d\n",
 606                                  ctrlreq->wValue, vdev->rhport);
 607
 608                         vdev->udev = urb->dev;
 609
 610                         spin_lock(&vdev->ud.lock);
 611                         vdev->ud.status = VDEV_ST_USED;
 612                         spin_unlock(&vdev->ud.lock);
 613
 614                         if (urb->status == -EINPROGRESS) {
 615                                 /* This request is successfully completed. */
 616                                 /* If not -EINPROGRESS, possibly unlinked. */
 617                                 urb->status = 0;
 618                         }
 619
 620                         goto no_need_xmit;
 621
 622                 case USB_REQ_GET_DESCRIPTOR:
 623                         if (ctrlreq->wValue == (USB_DT_DEVICE << 8))
 624                                 usbip_dbg_vhci_hc("Not yet?: "
 625                                                 "Get_Descriptor to device 0 "
 626                                                 "(get max pipe size)\n");
 627
 628                         /* FIXME: reference count? (usb_get_dev()) */
 629                         vdev->udev = urb->dev;
 630                         goto out;
 631
 632                 default:
 633                         /* NOT REACHED */
 634                         dev_err(dev, "invalid request to devnum 0 bRequest %u, "
 635                                 "wValue %u\n", ctrlreq->bRequest,
 636                                 ctrlreq->wValue);
 637                         ret =  -EINVAL;
 638                         goto no_need_xmit;
 639                 }
 640
 641         }
 642
 643 out:
 644         vhci_tx_urb(urb);
 645
 646         spin_unlock_irqrestore(&the_controller->lock, flags);
 647
 648         return 0;
 649
 650 no_need_xmit:
 651         usb_hcd_unlink_urb_from_ep(hcd, urb);
 652 no_need_unlink:
 653         spin_unlock_irqrestore(&the_controller->lock, flags);
 654
 655         usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
 656
 657         return ret;
 658 }
 659
 660 /*
 661  * vhci_rx gives back the urb after receiving the reply of the urb.  If an
 662  * unlink pdu is sent or not, vhci_rx receives a normal return pdu and gives
 663  * back its urb. For the driver unlinking the urb, the content of the urb is
 664  * not important, but the calling to its completion handler is important; the
 665  * completion of unlinking is notified by the completion handler.
 666  *
 667  *
 668  * CLIENT SIDE
 669  *
 670  * - When vhci_hcd receives RET_SUBMIT,
 671  *
 672  *      - case 1a). the urb of the pdu is not unlinking.
 673  *              - normal case
 674  *              => just give back the urb
 675  *
 676  *      - case 1b). the urb of the pdu is unlinking.
 677  *              - usbip.ko will return a reply of the unlinking request.
 678  *              => give back the urb now and go to case 2b).
 679  *
 680  * - When vhci_hcd receives RET_UNLINK,
 681  *
 682  *      - case 2a). a submit request is still pending in vhci_hcd.
 683  *              - urb was really pending in usbip.ko and urb_unlink_urb() was
 684  *                completed there.
 685  *              => free a pending submit request
 686  *              => notify unlink completeness by giving back the urb
 687  *
 688  *      - case 2b). a submit request is *not* pending in vhci_hcd.
 689  *              - urb was already given back to the core driver.
 690  *              => do not give back the urb
 691  *
 692  *
 693  * SERVER SIDE
 694  *
 695  * - When usbip receives CMD_UNLINK,
 696  *
 697  *      - case 3a). the urb of the unlink request is now in submission.
 698  *              => do usb_unlink_urb().
 699  *              => after the unlink is completed, send RET_UNLINK.
 700  *
 701  *      - case 3b). the urb of the unlink request is not in submission.
 702  *              - may be already completed or never be received
 703  *              => send RET_UNLINK
 704  *
 705  */
 706 static int vhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 707 {
 708         unsigned long flags;
 709         struct vhci_priv *priv;
 710         struct vhci_device *vdev;
 711
 712         usbip_uinfo("vhci_hcd: dequeue a urb %p\n", urb);
 713
 714
 715         spin_lock_irqsave(&the_controller->lock, flags);
 716
 717         priv = urb->hcpriv;
 718         if (!priv) {
 719                 /* URB was never linked! or will be soon given back by
 720                  * vhci_rx. */
 721                 spin_unlock_irqrestore(&the_controller->lock, flags);
 722                 return 0;
 723         }
 724
 725         {
 726                 int ret = 0;
 727                 ret = usb_hcd_check_unlink_urb(hcd, urb, status);
 728                 if (ret) {
 729                         spin_unlock_irqrestore(&the_controller->lock, flags);
 730                         return ret;
 731                 }
 732         }
 733
 734          /* send unlink request here? */
 735         vdev = priv->vdev;
 736
 737         if (!vdev->ud.tcp_socket) {
 738                 /* tcp connection is closed */
 739                 unsigned long flags2;
 740
 741                 spin_lock_irqsave(&vdev->priv_lock, flags2);
 742
 743                 usbip_uinfo("vhci_hcd: device %p seems to be disconnected\n",
 744                                                                         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                 usbip_uinfo("vhci_hcd: vhci_urb_dequeue() gives back urb %p\n",
 757                                                                         urb);
 758
 759                 usb_hcd_unlink_urb_from_ep(hcd, urb);
 760
 761                 spin_unlock_irqrestore(&the_controller->lock, flags);
 762                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 763                                                                 urb->status);
 764                 spin_lock_irqsave(&the_controller->lock, flags);
 765
 766         } else {
 767                 /* tcp connection is alive */
 768                 unsigned long flags2;
 769                 struct vhci_unlink *unlink;
 770
 771                 spin_lock_irqsave(&vdev->priv_lock, flags2);
 772
 773                 /* setup CMD_UNLINK pdu */
 774                 unlink = kzalloc(sizeof(struct vhci_unlink), GFP_ATOMIC);
 775                 if (!unlink) {
 776                         usbip_uerr("malloc vhci_unlink\n");
 777                         spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 778                         spin_unlock_irqrestore(&the_controller->lock, flags);
 779                         usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_MALLOC);
 780                         return -ENOMEM;
 781                 }
 782
 783                 unlink->seqnum = atomic_inc_return(&the_controller->seqnum);
 784                 if (unlink->seqnum == 0xffff)
 785                         usbip_uinfo("seqnum max\n");
 786
 787                 unlink->unlink_seqnum = priv->seqnum;
 788
 789                 usbip_uinfo("vhci_hcd: device %p seems to be still connected\n",
 790                                                                         vdev);
 791
 792                 /* send cmd_unlink and try to cancel the pending URB in the
 793                  * peer */
 794                 list_add_tail(&unlink->list, &vdev->unlink_tx);
 795                 wake_up(&vdev->waitq_tx);
 796
 797                 spin_unlock_irqrestore(&vdev->priv_lock, flags2);
 798         }
 799
 800
 801         if (!vdev->ud.tcp_socket) {
 802                 /* tcp connection is closed */
 803                 usbip_uinfo("vhci_hcd: vhci_urb_dequeue() gives back urb %p\n",
 804                                                                         urb);
 805
 806                 usb_hcd_unlink_urb_from_ep(hcd, urb);
 807
 808                 spin_unlock_irqrestore(&the_controller->lock, flags);
 809                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 810                                                                 urb->status);
 811                 spin_lock_irqsave(&the_controller->lock, flags);
 812         }
 813
 814         spin_unlock_irqrestore(&the_controller->lock, flags);
 815
 816         usbip_dbg_vhci_hc("leave\n");
 817         return 0;
 818 }
 819
 820
 821 static void vhci_device_unlink_cleanup(struct vhci_device *vdev)
 822 {
 823         struct vhci_unlink *unlink, *tmp;
 824
 825         spin_lock(&vdev->priv_lock);
 826
 827         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
 828                 list_del(&unlink->list);
 829                 kfree(unlink);
 830         }
 831
 832         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
 833                 list_del(&unlink->list);
 834                 kfree(unlink);
 835         }
 836
 837         spin_unlock(&vdev->priv_lock);
 838 }
 839
 840 /*
 841  * The important thing is that only one context begins cleanup.
 842  * This is why error handling and cleanup become simple.
 843  * We do not want to consider race condition as possible.
 844  */
 845 static void vhci_shutdown_connection(struct usbip_device *ud)
 846 {
 847         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 848
 849         /* need this? see stub_dev.c */
 850         if (ud->tcp_socket) {
 851                 usbip_udbg("shutdown tcp_socket %p\n", ud->tcp_socket);
 852                 kernel_sock_shutdown(ud->tcp_socket, SHUT_RDWR);
 853         }
 854
 855         usbip_stop_threads(&vdev->ud);
 856         usbip_uinfo("stop threads\n");
 857
 858         /* active connection is closed */
 859         if (vdev->ud.tcp_socket != NULL) {
 860                 sock_release(vdev->ud.tcp_socket);
 861                 vdev->ud.tcp_socket = NULL;
 862         }
 863         usbip_uinfo("release socket\n");
 864
 865         vhci_device_unlink_cleanup(vdev);
 866
 867         /*
 868          * rh_port_disconnect() is a trigger of ...
 869          *   usb_disable_device():
 870          *      disable all the endpoints for a USB device.
 871          *   usb_disable_endpoint():
 872          *      disable endpoints. pending urbs are unlinked(dequeued).
 873          *
 874          * NOTE: After calling rh_port_disconnect(), the USB device drivers of a
 875          * deteched device should release used urbs in a cleanup function(i.e.
 876          * xxx_disconnect()). Therefore, vhci_hcd does not need to release
 877          * pushed urbs and their private data in this function.
 878          *
 879          * NOTE: vhci_dequeue() must be considered carefully. When shutdowning
 880          * a connection, vhci_shutdown_connection() expects vhci_dequeue()
 881          * gives back pushed urbs and frees their private data by request of
 882          * the cleanup function of a USB driver. When unlinking a urb with an
 883          * active connection, vhci_dequeue() does not give back the urb which
 884          * is actually given back by vhci_rx after receiving its return pdu.
 885          *
 886          */
 887         rh_port_disconnect(vdev->rhport);
 888
 889         usbip_uinfo("disconnect device\n");
 890 }
 891
 892
 893 static void vhci_device_reset(struct usbip_device *ud)
 894 {
 895         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 896
 897         spin_lock(&ud->lock);
 898
 899         vdev->speed  = 0;
 900         vdev->devid  = 0;
 901
 902         ud->tcp_socket = NULL;
 903
 904         ud->status = VDEV_ST_NULL;
 905
 906         spin_unlock(&ud->lock);
 907 }
 908
 909 static void vhci_device_unusable(struct usbip_device *ud)
 910 {
 911         spin_lock(&ud->lock);
 912
 913         ud->status = VDEV_ST_ERROR;
 914
 915         spin_unlock(&ud->lock);
 916 }
 917
 918 static void vhci_device_init(struct vhci_device *vdev)
 919 {
 920         memset(vdev, 0, sizeof(*vdev));
 921
 922         usbip_task_init(&vdev->ud.tcp_rx, "vhci_rx", vhci_rx_loop);
 923         usbip_task_init(&vdev->ud.tcp_tx, "vhci_tx", vhci_tx_loop);
 924
 925         vdev->ud.side   = USBIP_VHCI;
 926         vdev->ud.status = VDEV_ST_NULL;
 927         /* vdev->ud.lock   = SPIN_LOCK_UNLOCKED; */
 928         spin_lock_init(&vdev->ud.lock);
 929
 930         INIT_LIST_HEAD(&vdev->priv_rx);
 931         INIT_LIST_HEAD(&vdev->priv_tx);
 932         INIT_LIST_HEAD(&vdev->unlink_tx);
 933         INIT_LIST_HEAD(&vdev->unlink_rx);
 934         /* vdev->priv_lock = SPIN_LOCK_UNLOCKED; */
 935         spin_lock_init(&vdev->priv_lock);
 936
 937         init_waitqueue_head(&vdev->waitq_tx);
 938
 939         vdev->ud.eh_ops.shutdown = vhci_shutdown_connection;
 940         vdev->ud.eh_ops.reset = vhci_device_reset;
 941         vdev->ud.eh_ops.unusable = vhci_device_unusable;
 942
 943         usbip_start_eh(&vdev->ud);
 944 }
 945
 946
 947 /*----------------------------------------------------------------------*/
 948
 949 static int vhci_start(struct usb_hcd *hcd)
 950 {
 951         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 952         int rhport;
 953         int err = 0;
 954
 955         usbip_dbg_vhci_hc("enter vhci_start\n");
 956
 957
 958         /* initialize private data of usb_hcd */
 959
 960         for (rhport = 0; rhport < VHCI_NPORTS; rhport++) {
 961                 struct vhci_device *vdev = &vhci->vdev[rhport];
 962                 vhci_device_init(vdev);
 963                 vdev->rhport = rhport;
 964         }
 965
 966         atomic_set(&vhci->seqnum, 0);
 967         spin_lock_init(&vhci->lock);
 968
 969
 970
 971         hcd->power_budget = 0; /* no limit */
 972         hcd->state  = HC_STATE_RUNNING;
 973         hcd->uses_new_polling = 1;
 974
 975
 976         /* vhci_hcd is now ready to be controlled through sysfs */
 977         err = sysfs_create_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 978         if (err) {
 979                 usbip_uerr("create sysfs files\n");
 980                 return err;
 981         }
 982
 983         return 0;
 984 }
 985
 986 static void vhci_stop(struct usb_hcd *hcd)
 987 {
 988         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
 989         int rhport = 0;
 990
 991         usbip_dbg_vhci_hc("stop VHCI controller\n");
 992
 993
 994         /* 1. remove the userland interface of vhci_hcd */
 995         sysfs_remove_group(&vhci_dev(vhci)->kobj, &dev_attr_group);
 996
 997         /* 2. shutdown all the ports of vhci_hcd */
 998         for (rhport = 0 ; rhport < VHCI_NPORTS; rhport++) {
 999                 struct vhci_device *vdev = &vhci->vdev[rhport];
1000
1001                 usbip_event_add(&vdev->ud, VDEV_EVENT_REMOVED);
1002                 usbip_stop_eh(&vdev->ud);
1003         }
1004
1005
1006         usbip_uinfo("vhci_stop done\n");
1007 }
1008
1009 /*----------------------------------------------------------------------*/
1010
1011 static int vhci_get_frame_number(struct usb_hcd *hcd)
1012 {
1013         usbip_uerr("Not yet implemented\n");
1014         return 0;
1015 }
1016
1017
1018 #ifdef CONFIG_PM
1019
1020 /* FIXME: suspend/resume */
1021 static int vhci_bus_suspend(struct usb_hcd *hcd)
1022 {
1023         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
1024
1025         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1026
1027         spin_lock_irq(&vhci->lock);
1028         /* vhci->rh_state = DUMMY_RH_SUSPENDED;
1029          * set_link_state(vhci); */
1030         hcd->state = HC_STATE_SUSPENDED;
1031         spin_unlock_irq(&vhci->lock);
1032
1033         return 0;
1034 }
1035
1036 static int vhci_bus_resume(struct usb_hcd *hcd)
1037 {
1038         struct vhci_hcd *vhci = hcd_to_vhci(hcd);
1039         int rc = 0;
1040
1041         dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
1042
1043         spin_lock_irq(&vhci->lock);
1044         if (!HCD_HW_ACCESSIBLE(hcd)) {
1045                 rc = -ESHUTDOWN;
1046         } else {
1047                 /* vhci->rh_state = DUMMY_RH_RUNNING;
1048                  * set_link_state(vhci);
1049                  * if (!list_empty(&vhci->urbp_list))
1050                  *      mod_timer(&vhci->timer, jiffies); */
1051                 hcd->state = HC_STATE_RUNNING;
1052         }
1053         spin_unlock_irq(&vhci->lock);
1054         return rc;
1055
1056         return 0;
1057 }
1058
1059 #else
1060
1061 #define vhci_bus_suspend      NULL
1062 #define vhci_bus_resume       NULL
1063 #endif
1064
1065
1066
1067 static struct hc_driver vhci_hc_driver = {
1068         .description    = driver_name,
1069         .product_desc   = driver_desc,
1070         .hcd_priv_size  = sizeof(struct vhci_hcd),
1071
1072         .flags          = HCD_USB2,
1073
1074         .start          = vhci_start,
1075         .stop           = vhci_stop,
1076
1077         .urb_enqueue    = vhci_urb_enqueue,
1078         .urb_dequeue    = vhci_urb_dequeue,
1079
1080         .get_frame_number = vhci_get_frame_number,
1081
1082         .hub_status_data = vhci_hub_status,
1083         .hub_control    = vhci_hub_control,
1084         .bus_suspend    = vhci_bus_suspend,
1085         .bus_resume     = vhci_bus_resume,
1086 };
1087
1088 static int vhci_hcd_probe(struct platform_device *pdev)
1089 {
1090         struct usb_hcd          *hcd;
1091         int                     ret;
1092
1093         usbip_uinfo("proving...\n");
1094
1095         usbip_dbg_vhci_hc("name %s id %d\n", pdev->name, pdev->id);
1096
1097         /* will be removed */
1098         if (pdev->dev.dma_mask) {
1099                 dev_info(&pdev->dev, "vhci_hcd DMA not supported\n");
1100                 return -EINVAL;
1101         }
1102
1103         /*
1104          * Allocate and initialize hcd.
1105          * Our private data is also allocated automatically.
1106          */
1107         hcd = usb_create_hcd(&vhci_hc_driver, &pdev->dev, dev_name(&pdev->dev));
1108         if (!hcd) {
1109                 usbip_uerr("create hcd failed\n");
1110                 return -ENOMEM;
1111         }
1112
1113
1114         /* this is private data for vhci_hcd */
1115         the_controller = hcd_to_vhci(hcd);
1116
1117         /*
1118          * Finish generic HCD structure initialization and register.
1119          * Call the driver's reset() and start() routines.
1120          */
1121         ret = usb_add_hcd(hcd, 0, 0);
1122         if (ret != 0) {
1123                 usbip_uerr("usb_add_hcd failed %d\n", ret);
1124                 usb_put_hcd(hcd);
1125                 the_controller = NULL;
1126                 return ret;
1127         }
1128
1129
1130         usbip_dbg_vhci_hc("bye\n");
1131         return 0;
1132 }
1133
1134
1135 static int vhci_hcd_remove(struct platform_device *pdev)
1136 {
1137         struct usb_hcd  *hcd;
1138
1139         hcd = platform_get_drvdata(pdev);
1140         if (!hcd)
1141                 return 0;
1142
1143         /*
1144          * Disconnects the root hub,
1145          * then reverses the effects of usb_add_hcd(),
1146          * invoking the HCD's stop() methods.
1147          */
1148         usb_remove_hcd(hcd);
1149         usb_put_hcd(hcd);
1150         the_controller = NULL;
1151
1152
1153         return 0;
1154 }
1155
1156
1157
1158 #ifdef CONFIG_PM
1159
1160 /* what should happen for USB/IP under suspend/resume? */
1161 static int vhci_hcd_suspend(struct platform_device *pdev, pm_message_t state)
1162 {
1163         struct usb_hcd *hcd;
1164         int rhport = 0;
1165         int connected = 0;
1166         int ret = 0;
1167
1168         dev_dbg(&pdev->dev, "%s\n", __func__);
1169
1170         hcd = platform_get_drvdata(pdev);
1171
1172         spin_lock(&the_controller->lock);
1173
1174         for (rhport = 0; rhport < VHCI_NPORTS; rhport++)
1175                 if (the_controller->port_status[rhport] &
1176                                                 USB_PORT_STAT_CONNECTION)
1177                         connected += 1;
1178
1179         spin_unlock(&the_controller->lock);
1180
1181         if (connected > 0) {
1182                 usbip_uinfo("We have %d active connection%s. Do not suspend.\n",
1183                                 connected, (connected == 1 ? "" : "s"));
1184                 ret =  -EBUSY;
1185         } else {
1186                 usbip_uinfo("suspend vhci_hcd");
1187                 clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1188         }
1189
1190         return ret;
1191 }
1192
1193 static int vhci_hcd_resume(struct platform_device *pdev)
1194 {
1195         struct usb_hcd *hcd;
1196
1197         dev_dbg(&pdev->dev, "%s\n", __func__);
1198
1199         hcd = platform_get_drvdata(pdev);
1200         set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1201         usb_hcd_poll_rh_status(hcd);
1202
1203         return 0;
1204 }
1205
1206 #else
1207
1208 #define vhci_hcd_suspend        NULL
1209 #define vhci_hcd_resume         NULL
1210
1211 #endif
1212
1213
1214 static struct platform_driver vhci_driver = {
1215         .probe  = vhci_hcd_probe,
1216         .remove = __devexit_p(vhci_hcd_remove),
1217         .suspend = vhci_hcd_suspend,
1218         .resume = vhci_hcd_resume,
1219         .driver = {
1220                 .name = (char *) driver_name,
1221                 .owner = THIS_MODULE,
1222         },
1223 };
1224
1225 /*----------------------------------------------------------------------*/
1226
1227 /*
1228  * The VHCI 'device' is 'virtual'; not a real plug&play hardware.
1229  * We need to add this virtual device as a platform device arbitrarily:
1230  *      1. platform_device_register()
1231  */
1232 static void the_pdev_release(struct device *dev)
1233 {
1234         return;
1235 }
1236
1237 static struct platform_device the_pdev = {
1238         /* should be the same name as driver_name */
1239         .name = (char *) driver_name,
1240         .id = -1,
1241         .dev = {
1242                 /* .driver = &vhci_driver, */
1243                 .release = the_pdev_release,
1244         },
1245 };
1246
1247 static int __init vhci_init(void)
1248 {
1249         int ret;
1250
1251         usbip_dbg_vhci_hc("enter\n");
1252         if (usb_disabled())
1253                 return -ENODEV;
1254
1255         printk(KERN_INFO KBUILD_MODNAME ": %s, %s\n", driver_name,
1256                DRIVER_VERSION);
1257
1258         ret = platform_driver_register(&vhci_driver);
1259         if (ret < 0)
1260                 goto err_driver_register;
1261
1262         ret = platform_device_register(&the_pdev);
1263         if (ret < 0)
1264                 goto err_platform_device_register;
1265
1266         usbip_dbg_vhci_hc("bye\n");
1267         return ret;
1268
1269         /* error occurred */
1270 err_platform_device_register:
1271         platform_driver_unregister(&vhci_driver);
1272
1273 err_driver_register:
1274         usbip_dbg_vhci_hc("bye\n");
1275         return ret;
1276 }
1277 module_init(vhci_init);
1278
1279 static void __exit vhci_cleanup(void)
1280 {
1281         usbip_dbg_vhci_hc("enter\n");
1282
1283         platform_device_unregister(&the_pdev);
1284         platform_driver_unregister(&vhci_driver);
1285
1286         usbip_dbg_vhci_hc("bye\n");
1287 }
1288 module_exit(vhci_cleanup);