drivers/usb/core/hcd.c

   1 /*
   2  * (C) Copyright Linus Torvalds 1999
   3  * (C) Copyright Johannes Erdfelt 1999-2001
   4  * (C) Copyright Andreas Gal 1999
   5  * (C) Copyright Gregory P. Smith 1999
   6  * (C) Copyright Deti Fliegl 1999
   7  * (C) Copyright Randy Dunlap 2000
   8  * (C) Copyright David Brownell 2000-2002
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License as published by the
  12  * Free Software Foundation; either version 2 of the License, or (at your
  13  * option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  17  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  18  * for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software Foundation,
  22  * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  */
  24
  25 #include <linux/module.h>
  26 #include <linux/version.h>
  27 #include <linux/kernel.h>
  28 #include <linux/slab.h>
  29 #include <linux/completion.h>
  30 #include <linux/utsname.h>
  31 #include <linux/mm.h>
  32 #include <asm/io.h>
  33 #include <linux/device.h>
  34 #include <linux/dma-mapping.h>
  35 #include <linux/mutex.h>
  36 #include <asm/irq.h>
  37 #include <asm/byteorder.h>
  38 #include <asm/unaligned.h>
  39 #include <linux/platform_device.h>
  40 #include <linux/workqueue.h>
  41
  42 #include <linux/usb.h>
  43
  44 #include "usb.h"
  45 #include "hcd.h"
  46 #include "hub.h"
  47
  48
  49 /*-------------------------------------------------------------------------*/
  50
  51 /*
  52  * USB Host Controller Driver framework
  53  *
  54  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
  55  * HCD-specific behaviors/bugs.
  56  *
  57  * This does error checks, tracks devices and urbs, and delegates to a
  58  * "hc_driver" only for code (and data) that really needs to know about
  59  * hardware differences.  That includes root hub registers, i/o queues,
  60  * and so on ... but as little else as possible.
  61  *
  62  * Shared code includes most of the "root hub" code (these are emulated,
  63  * though each HC's hardware works differently) and PCI glue, plus request
  64  * tracking overhead.  The HCD code should only block on spinlocks or on
  65  * hardware handshaking; blocking on software events (such as other kernel
  66  * threads releasing resources, or completing actions) is all generic.
  67  *
  68  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
  69  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
  70  * only by the hub driver ... and that neither should be seen or used by
  71  * usb client device drivers.
  72  *
  73  * Contributors of ideas or unattributed patches include: David Brownell,
  74  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
  75  *
  76  * HISTORY:
  77  * 2002-02-21   Pull in most of the usb_bus support from usb.c; some
  78  *              associated cleanup.  "usb_hcd" still != "usb_bus".
  79  * 2001-12-12   Initial patch version for Linux 2.5.1 kernel.
  80  */
  81
  82 /*-------------------------------------------------------------------------*/
  83
  84 /* host controllers we manage */
  85 LIST_HEAD (usb_bus_list);
  86 EXPORT_SYMBOL_GPL (usb_bus_list);
  87
  88 /* used when allocating bus numbers */
  89 #define USB_MAXBUS              64
  90 struct usb_busmap {
  91         unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))];
  92 };
  93 static struct usb_busmap busmap;
  94
  95 /* used when updating list of hcds */
  96 DEFINE_MUTEX(usb_bus_list_lock);        /* exported only for usbfs */
  97 EXPORT_SYMBOL_GPL (usb_bus_list_lock);
  98
  99 /* used for controlling access to virtual root hubs */
 100 static DEFINE_SPINLOCK(hcd_root_hub_lock);
 101
 102 /* used when updating an endpoint's URB list */
 103 static DEFINE_SPINLOCK(hcd_urb_list_lock);
 104
 105 /* wait queue for synchronous unlinks */
 106 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
 107
 108 static inline int is_root_hub(struct usb_device *udev)
 109 {
 110         return (udev->parent == NULL);
 111 }
 112
 113 /*-------------------------------------------------------------------------*/
 114
 115 /*
 116  * Sharable chunks of root hub code.
 117  */
 118
 119 /*-------------------------------------------------------------------------*/
 120
 121 #define KERNEL_REL      ((LINUX_VERSION_CODE >> 16) & 0x0ff)
 122 #define KERNEL_VER      ((LINUX_VERSION_CODE >> 8) & 0x0ff)
 123
 124 /* usb 2.0 root hub device descriptor */
 125 static const u8 usb2_rh_dev_descriptor [18] = {
 126         0x12,       /*  __u8  bLength; */
 127         0x01,       /*  __u8  bDescriptorType; Device */
 128         0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
 129
 130         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 131         0x00,       /*  __u8  bDeviceSubClass; */
 132         0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 133         0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 134
 135         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation */
 136         0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 137         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 138
 139         0x03,       /*  __u8  iManufacturer; */
 140         0x02,       /*  __u8  iProduct; */
 141         0x01,       /*  __u8  iSerialNumber; */
 142         0x01        /*  __u8  bNumConfigurations; */
 143 };
 144
 145 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
 146
 147 /* usb 1.1 root hub device descriptor */
 148 static const u8 usb11_rh_dev_descriptor [18] = {
 149         0x12,       /*  __u8  bLength; */
 150         0x01,       /*  __u8  bDescriptorType; Device */
 151         0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
 152
 153         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 154         0x00,       /*  __u8  bDeviceSubClass; */
 155         0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
 156         0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 157
 158         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation */
 159         0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
 160         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 161
 162         0x03,       /*  __u8  iManufacturer; */
 163         0x02,       /*  __u8  iProduct; */
 164         0x01,       /*  __u8  iSerialNumber; */
 165         0x01        /*  __u8  bNumConfigurations; */
 166 };
 167
 168
 169 /*-------------------------------------------------------------------------*/
 170
 171 /* Configuration descriptors for our root hubs */
 172
 173 static const u8 fs_rh_config_descriptor [] = {
 174
 175         /* one configuration */
 176         0x09,       /*  __u8  bLength; */
 177         0x02,       /*  __u8  bDescriptorType; Configuration */
 178         0x19, 0x00, /*  __le16 wTotalLength; */
 179         0x01,       /*  __u8  bNumInterfaces; (1) */
 180         0x01,       /*  __u8  bConfigurationValue; */
 181         0x00,       /*  __u8  iConfiguration; */
 182         0xc0,       /*  __u8  bmAttributes;
 183                                  Bit 7: must be set,
 184                                      6: Self-powered,
 185                                      5: Remote wakeup,
 186                                      4..0: resvd */
 187         0x00,       /*  __u8  MaxPower; */
 188
 189         /* USB 1.1:
 190          * USB 2.0, single TT organization (mandatory):
 191          *      one interface, protocol 0
 192          *
 193          * USB 2.0, multiple TT organization (optional):
 194          *      two interfaces, protocols 1 (like single TT)
 195          *      and 2 (multiple TT mode) ... config is
 196          *      sometimes settable
 197          *      NOT IMPLEMENTED
 198          */
 199
 200         /* one interface */
 201         0x09,       /*  __u8  if_bLength; */
 202         0x04,       /*  __u8  if_bDescriptorType; Interface */
 203         0x00,       /*  __u8  if_bInterfaceNumber; */
 204         0x00,       /*  __u8  if_bAlternateSetting; */
 205         0x01,       /*  __u8  if_bNumEndpoints; */
 206         0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 207         0x00,       /*  __u8  if_bInterfaceSubClass; */
 208         0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 209         0x00,       /*  __u8  if_iInterface; */
 210
 211         /* one endpoint (status change endpoint) */
 212         0x07,       /*  __u8  ep_bLength; */
 213         0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
 214         0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 215         0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 216         0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
 217         0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
 218 };
 219
 220 static const u8 hs_rh_config_descriptor [] = {
 221
 222         /* one configuration */
 223         0x09,       /*  __u8  bLength; */
 224         0x02,       /*  __u8  bDescriptorType; Configuration */
 225         0x19, 0x00, /*  __le16 wTotalLength; */
 226         0x01,       /*  __u8  bNumInterfaces; (1) */
 227         0x01,       /*  __u8  bConfigurationValue; */
 228         0x00,       /*  __u8  iConfiguration; */
 229         0xc0,       /*  __u8  bmAttributes;
 230                                  Bit 7: must be set,
 231                                      6: Self-powered,
 232                                      5: Remote wakeup,
 233                                      4..0: resvd */
 234         0x00,       /*  __u8  MaxPower; */
 235
 236         /* USB 1.1:
 237          * USB 2.0, single TT organization (mandatory):
 238          *      one interface, protocol 0
 239          *
 240          * USB 2.0, multiple TT organization (optional):
 241          *      two interfaces, protocols 1 (like single TT)
 242          *      and 2 (multiple TT mode) ... config is
 243          *      sometimes settable
 244          *      NOT IMPLEMENTED
 245          */
 246
 247         /* one interface */
 248         0x09,       /*  __u8  if_bLength; */
 249         0x04,       /*  __u8  if_bDescriptorType; Interface */
 250         0x00,       /*  __u8  if_bInterfaceNumber; */
 251         0x00,       /*  __u8  if_bAlternateSetting; */
 252         0x01,       /*  __u8  if_bNumEndpoints; */
 253         0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 254         0x00,       /*  __u8  if_bInterfaceSubClass; */
 255         0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 256         0x00,       /*  __u8  if_iInterface; */
 257
 258         /* one endpoint (status change endpoint) */
 259         0x07,       /*  __u8  ep_bLength; */
 260         0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
 261         0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 262         0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 263                     /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 264                      * see hub.c:hub_configure() for details. */
 265         (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 266         0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 267 };
 268
 269 /*-------------------------------------------------------------------------*/
 270
 271 /*
 272  * helper routine for returning string descriptors in UTF-16LE
 273  * input can actually be ISO-8859-1; ASCII is its 7-bit subset
 274  */
 275 static int ascii2utf (char *s, u8 *utf, int utfmax)
 276 {
 277         int retval;
 278
 279         for (retval = 0; *s && utfmax > 1; utfmax -= 2, retval += 2) {
 280                 *utf++ = *s++;
 281                 *utf++ = 0;
 282         }
 283         if (utfmax > 0) {
 284                 *utf = *s;
 285                 ++retval;
 286         }
 287         return retval;
 288 }
 289
 290 /*
 291  * rh_string - provides manufacturer, product and serial strings for root hub
 292  * @id: the string ID number (1: serial number, 2: product, 3: vendor)
 293  * @hcd: the host controller for this root hub
 294  * @data: return packet in UTF-16 LE
 295  * @len: length of the return packet
 296  *
 297  * Produces either a manufacturer, product or serial number string for the
 298  * virtual root hub device.
 299  */
 300 static int rh_string (
 301         int             id,
 302         struct usb_hcd  *hcd,
 303         u8              *data,
 304         int             len
 305 ) {
 306         char buf [100];
 307
 308         // language ids
 309         if (id == 0) {
 310                 buf[0] = 4;    buf[1] = 3;      /* 4 bytes string data */
 311                 buf[2] = 0x09; buf[3] = 0x04;   /* MSFT-speak for "en-us" */
 312                 len = min (len, 4);
 313                 memcpy (data, buf, len);
 314                 return len;
 315
 316         // serial number
 317         } else if (id == 1) {
 318                 strlcpy (buf, hcd->self.bus_name, sizeof buf);
 319
 320         // product description
 321         } else if (id == 2) {
 322                 strlcpy (buf, hcd->product_desc, sizeof buf);
 323
 324         // id 3 == vendor description
 325         } else if (id == 3) {
 326                 snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
 327                         init_utsname()->release, hcd->driver->description);
 328
 329         // unsupported IDs --> "protocol stall"
 330         } else
 331                 return -EPIPE;
 332
 333         switch (len) {          /* All cases fall through */
 334         default:
 335                 len = 2 + ascii2utf (buf, data + 2, len - 2);
 336         case 2:
 337                 data [1] = 3;   /* type == string */
 338         case 1:
 339                 data [0] = 2 * (strlen (buf) + 1);
 340         case 0:
 341                 ;               /* Compiler wants a statement here */
 342         }
 343         return len;
 344 }
 345
 346
 347 /* Root hub control transfers execute synchronously */
 348 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
 349 {
 350         struct usb_ctrlrequest *cmd;
 351         u16             typeReq, wValue, wIndex, wLength;
 352         u8              *ubuf = urb->transfer_buffer;
 353         u8              tbuf [sizeof (struct usb_hub_descriptor)]
 354                 __attribute__((aligned(4)));
 355         const u8        *bufp = tbuf;
 356         int             len = 0;
 357         int             status;
 358         int             n;
 359         u8              patch_wakeup = 0;
 360         u8              patch_protocol = 0;
 361
 362         might_sleep();
 363
 364         spin_lock_irq(&hcd_root_hub_lock);
 365         status = usb_hcd_link_urb_to_ep(hcd, urb);
 366         spin_unlock_irq(&hcd_root_hub_lock);
 367         if (status)
 368                 return status;
 369         urb->hcpriv = hcd;      /* Indicate it's queued */
 370
 371         cmd = (struct usb_ctrlrequest *) urb->setup_packet;
 372         typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
 373         wValue   = le16_to_cpu (cmd->wValue);
 374         wIndex   = le16_to_cpu (cmd->wIndex);
 375         wLength  = le16_to_cpu (cmd->wLength);
 376
 377         if (wLength > urb->transfer_buffer_length)
 378                 goto error;
 379
 380         urb->actual_length = 0;
 381         switch (typeReq) {
 382
 383         /* DEVICE REQUESTS */
 384
 385         /* The root hub's remote wakeup enable bit is implemented using
 386          * driver model wakeup flags.  If this system supports wakeup
 387          * through USB, userspace may change the default "allow wakeup"
 388          * policy through sysfs or these calls.
 389          *
 390          * Most root hubs support wakeup from downstream devices, for
 391          * runtime power management (disabling USB clocks and reducing
 392          * VBUS power usage).  However, not all of them do so; silicon,
 393          * board, and BIOS bugs here are not uncommon, so these can't
 394          * be treated quite like external hubs.
 395          *
 396          * Likewise, not all root hubs will pass wakeup events upstream,
 397          * to wake up the whole system.  So don't assume root hub and
 398          * controller capabilities are identical.
 399          */
 400
 401         case DeviceRequest | USB_REQ_GET_STATUS:
 402                 tbuf [0] = (device_may_wakeup(&hcd->self.root_hub->dev)
 403                                         << USB_DEVICE_REMOTE_WAKEUP)
 404                                 | (1 << USB_DEVICE_SELF_POWERED);
 405                 tbuf [1] = 0;
 406                 len = 2;
 407                 break;
 408         case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
 409                 if (wValue == USB_DEVICE_REMOTE_WAKEUP)
 410                         device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
 411                 else
 412                         goto error;
 413                 break;
 414         case DeviceOutRequest | USB_REQ_SET_FEATURE:
 415                 if (device_can_wakeup(&hcd->self.root_hub->dev)
 416                                 && wValue == USB_DEVICE_REMOTE_WAKEUP)
 417                         device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
 418                 else
 419                         goto error;
 420                 break;
 421         case DeviceRequest | USB_REQ_GET_CONFIGURATION:
 422                 tbuf [0] = 1;
 423                 len = 1;
 424                         /* FALLTHROUGH */
 425         case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
 426                 break;
 427         case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 428                 switch (wValue & 0xff00) {
 429                 case USB_DT_DEVICE << 8:
 430                         if (hcd->driver->flags & HCD_USB2)
 431                                 bufp = usb2_rh_dev_descriptor;
 432                         else if (hcd->driver->flags & HCD_USB11)
 433                                 bufp = usb11_rh_dev_descriptor;
 434                         else
 435                                 goto error;
 436                         len = 18;
 437                         if (hcd->has_tt)
 438                                 patch_protocol = 1;
 439                         break;
 440                 case USB_DT_CONFIG << 8:
 441                         if (hcd->driver->flags & HCD_USB2) {
 442                                 bufp = hs_rh_config_descriptor;
 443                                 len = sizeof hs_rh_config_descriptor;
 444                         } else {
 445                                 bufp = fs_rh_config_descriptor;
 446                                 len = sizeof fs_rh_config_descriptor;
 447                         }
 448                         if (device_can_wakeup(&hcd->self.root_hub->dev))
 449                                 patch_wakeup = 1;
 450                         break;
 451                 case USB_DT_STRING << 8:
 452                         n = rh_string (wValue & 0xff, hcd, ubuf, wLength);
 453                         if (n < 0)
 454                                 goto error;
 455                         urb->actual_length = n;
 456                         break;
 457                 default:
 458                         goto error;
 459                 }
 460                 break;
 461         case DeviceRequest | USB_REQ_GET_INTERFACE:
 462                 tbuf [0] = 0;
 463                 len = 1;
 464                         /* FALLTHROUGH */
 465         case DeviceOutRequest | USB_REQ_SET_INTERFACE:
 466                 break;
 467         case DeviceOutRequest | USB_REQ_SET_ADDRESS:
 468                 // wValue == urb->dev->devaddr
 469                 dev_dbg (hcd->self.controller, "root hub device address %d\n",
 470                         wValue);
 471                 break;
 472
 473         /* INTERFACE REQUESTS (no defined feature/status flags) */
 474
 475         /* ENDPOINT REQUESTS */
 476
 477         case EndpointRequest | USB_REQ_GET_STATUS:
 478                 // ENDPOINT_HALT flag
 479                 tbuf [0] = 0;
 480                 tbuf [1] = 0;
 481                 len = 2;
 482                         /* FALLTHROUGH */
 483         case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
 484         case EndpointOutRequest | USB_REQ_SET_FEATURE:
 485                 dev_dbg (hcd->self.controller, "no endpoint features yet\n");
 486                 break;
 487
 488         /* CLASS REQUESTS (and errors) */
 489
 490         default:
 491                 /* non-generic request */
 492                 switch (typeReq) {
 493                 case GetHubStatus:
 494                 case GetPortStatus:
 495                         len = 4;
 496                         break;
 497                 case GetHubDescriptor:
 498                         len = sizeof (struct usb_hub_descriptor);
 499                         break;
 500                 }
 501                 status = hcd->driver->hub_control (hcd,
 502                         typeReq, wValue, wIndex,
 503                         tbuf, wLength);
 504                 break;
 505 error:
 506                 /* "protocol stall" on error */
 507                 status = -EPIPE;
 508         }
 509
 510         if (status) {
 511                 len = 0;
 512                 if (status != -EPIPE) {
 513                         dev_dbg (hcd->self.controller,
 514                                 "CTRL: TypeReq=0x%x val=0x%x "
 515                                 "idx=0x%x len=%d ==> %d\n",
 516                                 typeReq, wValue, wIndex,
 517                                 wLength, status);
 518                 }
 519         }
 520         if (len) {
 521                 if (urb->transfer_buffer_length < len)
 522                         len = urb->transfer_buffer_length;
 523                 urb->actual_length = len;
 524                 // always USB_DIR_IN, toward host
 525                 memcpy (ubuf, bufp, len);
 526
 527                 /* report whether RH hardware supports remote wakeup */
 528                 if (patch_wakeup &&
 529                                 len > offsetof (struct usb_config_descriptor,
 530                                                 bmAttributes))
 531                         ((struct usb_config_descriptor *)ubuf)->bmAttributes
 532                                 |= USB_CONFIG_ATT_WAKEUP;
 533
 534                 /* report whether RH hardware has an integrated TT */
 535                 if (patch_protocol &&
 536                                 len > offsetof(struct usb_device_descriptor,
 537                                                 bDeviceProtocol))
 538                         ((struct usb_device_descriptor *) ubuf)->
 539                                         bDeviceProtocol = 1;
 540         }
 541
 542         /* any errors get returned through the urb completion */
 543         spin_lock_irq(&hcd_root_hub_lock);
 544         usb_hcd_unlink_urb_from_ep(hcd, urb);
 545
 546         /* This peculiar use of spinlocks echoes what real HC drivers do.
 547          * Avoiding calls to local_irq_disable/enable makes the code
 548          * RT-friendly.
 549          */
 550         spin_unlock(&hcd_root_hub_lock);
 551         usb_hcd_giveback_urb(hcd, urb, status);
 552         spin_lock(&hcd_root_hub_lock);
 553
 554         spin_unlock_irq(&hcd_root_hub_lock);
 555         return 0;
 556 }
 557
 558 /*-------------------------------------------------------------------------*/
 559
 560 /*
 561  * Root Hub interrupt transfers are polled using a timer if the
 562  * driver requests it; otherwise the driver is responsible for
 563  * calling usb_hcd_poll_rh_status() when an event occurs.
 564  *
 565  * Completions are called in_interrupt(), but they may or may not
 566  * be in_irq().
 567  */
 568 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
 569 {
 570         struct urb      *urb;
 571         int             length;
 572         unsigned long   flags;
 573         char            buffer[4];      /* Any root hubs with > 31 ports? */
 574
 575         if (unlikely(!hcd->rh_registered))
 576                 return;
 577         if (!hcd->uses_new_polling && !hcd->status_urb)
 578                 return;
 579
 580         length = hcd->driver->hub_status_data(hcd, buffer);
 581         if (length > 0) {
 582
 583                 /* try to complete the status urb */
 584                 spin_lock_irqsave(&hcd_root_hub_lock, flags);
 585                 urb = hcd->status_urb;
 586                 if (urb) {
 587                         hcd->poll_pending = 0;
 588                         hcd->status_urb = NULL;
 589                         urb->actual_length = length;
 590                         memcpy(urb->transfer_buffer, buffer, length);
 591
 592                         usb_hcd_unlink_urb_from_ep(hcd, urb);
 593                         spin_unlock(&hcd_root_hub_lock);
 594                         usb_hcd_giveback_urb(hcd, urb, 0);
 595                         spin_lock(&hcd_root_hub_lock);
 596                 } else {
 597                         length = 0;
 598                         hcd->poll_pending = 1;
 599                 }
 600                 spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 601         }
 602
 603         /* The USB 2.0 spec says 256 ms.  This is close enough and won't
 604          * exceed that limit if HZ is 100. The math is more clunky than
 605          * maybe expected, this is to make sure that all timers for USB devices
 606          * fire at the same time to give the CPU a break inbetween */
 607         if (hcd->uses_new_polling ? hcd->poll_rh :
 608                         (length == 0 && hcd->status_urb != NULL))
 609                 mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 610 }
 611 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
 612
 613 /* timer callback */
 614 static void rh_timer_func (unsigned long _hcd)
 615 {
 616         usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
 617 }
 618
 619 /*-------------------------------------------------------------------------*/
 620
 621 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
 622 {
 623         int             retval;
 624         unsigned long   flags;
 625         int             len = 1 + (urb->dev->maxchild / 8);
 626
 627         spin_lock_irqsave (&hcd_root_hub_lock, flags);
 628         if (hcd->status_urb || urb->transfer_buffer_length < len) {
 629                 dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
 630                 retval = -EINVAL;
 631                 goto done;
 632         }
 633
 634         retval = usb_hcd_link_urb_to_ep(hcd, urb);
 635         if (retval)
 636                 goto done;
 637
 638         hcd->status_urb = urb;
 639         urb->hcpriv = hcd;      /* indicate it's queued */
 640         if (!hcd->uses_new_polling)
 641                 mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 642
 643         /* If a status change has already occurred, report it ASAP */
 644         else if (hcd->poll_pending)
 645                 mod_timer(&hcd->rh_timer, jiffies);
 646         retval = 0;
 647  done:
 648         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
 649         return retval;
 650 }
 651
 652 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
 653 {
 654         if (usb_endpoint_xfer_int(&urb->ep->desc))
 655                 return rh_queue_status (hcd, urb);
 656         if (usb_endpoint_xfer_control(&urb->ep->desc))
 657                 return rh_call_control (hcd, urb);
 658         return -EINVAL;
 659 }
 660
 661 /*-------------------------------------------------------------------------*/
 662
 663 /* Unlinks of root-hub control URBs are legal, but they don't do anything
 664  * since these URBs always execute synchronously.
 665  */
 666 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 667 {
 668         unsigned long   flags;
 669         int             rc;
 670
 671         spin_lock_irqsave(&hcd_root_hub_lock, flags);
 672         rc = usb_hcd_check_unlink_urb(hcd, urb, status);
 673         if (rc)
 674                 goto done;
 675
 676         if (usb_endpoint_num(&urb->ep->desc) == 0) {    /* Control URB */
 677                 ;       /* Do nothing */
 678
 679         } else {                                /* Status URB */
 680                 if (!hcd->uses_new_polling)
 681                         del_timer (&hcd->rh_timer);
 682                 if (urb == hcd->status_urb) {
 683                         hcd->status_urb = NULL;
 684                         usb_hcd_unlink_urb_from_ep(hcd, urb);
 685
 686                         spin_unlock(&hcd_root_hub_lock);
 687                         usb_hcd_giveback_urb(hcd, urb, status);
 688                         spin_lock(&hcd_root_hub_lock);
 689                 }
 690         }
 691  done:
 692         spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 693         return rc;
 694 }
 695
 696
 697
 698 /*
 699  * Show & store the current value of authorized_default
 700  */
 701 static ssize_t usb_host_authorized_default_show(struct device *dev,
 702                                                 struct device_attribute *attr,
 703                                                 char *buf)
 704 {
 705         struct usb_device *rh_usb_dev = to_usb_device(dev);
 706         struct usb_bus *usb_bus = rh_usb_dev->bus;
 707         struct usb_hcd *usb_hcd;
 708
 709         if (usb_bus == NULL)    /* FIXME: not sure if this case is possible */
 710                 return -ENODEV;
 711         usb_hcd = bus_to_hcd(usb_bus);
 712         return snprintf(buf, PAGE_SIZE, "%u\n", usb_hcd->authorized_default);
 713 }
 714
 715 static ssize_t usb_host_authorized_default_store(struct device *dev,
 716                                                  struct device_attribute *attr,
 717                                                  const char *buf, size_t size)
 718 {
 719         ssize_t result;
 720         unsigned val;
 721         struct usb_device *rh_usb_dev = to_usb_device(dev);
 722         struct usb_bus *usb_bus = rh_usb_dev->bus;
 723         struct usb_hcd *usb_hcd;
 724
 725         if (usb_bus == NULL)    /* FIXME: not sure if this case is possible */
 726                 return -ENODEV;
 727         usb_hcd = bus_to_hcd(usb_bus);
 728         result = sscanf(buf, "%u\n", &val);
 729         if (result == 1) {
 730                 usb_hcd->authorized_default = val? 1 : 0;
 731                 result = size;
 732         }
 733         else
 734                 result = -EINVAL;
 735         return result;
 736 }
 737
 738 static DEVICE_ATTR(authorized_default, 0644,
 739             usb_host_authorized_default_show,
 740             usb_host_authorized_default_store);
 741
 742
 743 /* Group all the USB bus attributes */
 744 static struct attribute *usb_bus_attrs[] = {
 745                 &dev_attr_authorized_default.attr,
 746                 NULL,
 747 };
 748
 749 static struct attribute_group usb_bus_attr_group = {
 750         .name = NULL,   /* we want them in the same directory */
 751         .attrs = usb_bus_attrs,
 752 };
 753
 754
 755
 756 /*-------------------------------------------------------------------------*/
 757
 758 static struct class *usb_host_class;
 759
 760 int usb_host_init(void)
 761 {
 762         int retval = 0;
 763
 764         usb_host_class = class_create(THIS_MODULE, "usb_host");
 765         if (IS_ERR(usb_host_class))
 766                 retval = PTR_ERR(usb_host_class);
 767         return retval;
 768 }
 769
 770 void usb_host_cleanup(void)
 771 {
 772         class_destroy(usb_host_class);
 773 }
 774
 775 /**
 776  * usb_bus_init - shared initialization code
 777  * @bus: the bus structure being initialized
 778  *
 779  * This code is used to initialize a usb_bus structure, memory for which is
 780  * separately managed.
 781  */
 782 static void usb_bus_init (struct usb_bus *bus)
 783 {
 784         memset (&bus->devmap, 0, sizeof(struct usb_devmap));
 785
 786         bus->devnum_next = 1;
 787
 788         bus->root_hub = NULL;
 789         bus->busnum = -1;
 790         bus->bandwidth_allocated = 0;
 791         bus->bandwidth_int_reqs  = 0;
 792         bus->bandwidth_isoc_reqs = 0;
 793
 794         INIT_LIST_HEAD (&bus->bus_list);
 795 }
 796
 797 /*-------------------------------------------------------------------------*/
 798
 799 /**
 800  * usb_register_bus - registers the USB host controller with the usb core
 801  * @bus: pointer to the bus to register
 802  * Context: !in_interrupt()
 803  *
 804  * Assigns a bus number, and links the controller into usbcore data
 805  * structures so that it can be seen by scanning the bus list.
 806  */
 807 static int usb_register_bus(struct usb_bus *bus)
 808 {
 809         int result = -E2BIG;
 810         int busnum;
 811
 812         mutex_lock(&usb_bus_list_lock);
 813         busnum = find_next_zero_bit (busmap.busmap, USB_MAXBUS, 1);
 814         if (busnum >= USB_MAXBUS) {
 815                 printk (KERN_ERR "%s: too many buses\n", usbcore_name);
 816                 goto error_find_busnum;
 817         }
 818         set_bit (busnum, busmap.busmap);
 819         bus->busnum = busnum;
 820
 821         bus->dev = device_create_drvdata(usb_host_class, bus->controller,
 822                                          MKDEV(0, 0), bus,
 823                                          "usb_host%d", busnum);
 824         result = PTR_ERR(bus->dev);
 825         if (IS_ERR(bus->dev))
 826                 goto error_create_class_dev;
 827
 828         /* Add it to the local list of buses */
 829         list_add (&bus->bus_list, &usb_bus_list);
 830         mutex_unlock(&usb_bus_list_lock);
 831
 832         usb_notify_add_bus(bus);
 833
 834         dev_info (bus->controller, "new USB bus registered, assigned bus "
 835                   "number %d\n", bus->busnum);
 836         return 0;
 837
 838 error_create_class_dev:
 839         clear_bit(busnum, busmap.busmap);
 840 error_find_busnum:
 841         mutex_unlock(&usb_bus_list_lock);
 842         return result;
 843 }
 844
 845 /**
 846  * usb_deregister_bus - deregisters the USB host controller
 847  * @bus: pointer to the bus to deregister
 848  * Context: !in_interrupt()
 849  *
 850  * Recycles the bus number, and unlinks the controller from usbcore data
 851  * structures so that it won't be seen by scanning the bus list.
 852  */
 853 static void usb_deregister_bus (struct usb_bus *bus)
 854 {
 855         dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
 856
 857         /*
 858          * NOTE: make sure that all the devices are removed by the
 859          * controller code, as well as having it call this when cleaning
 860          * itself up
 861          */
 862         mutex_lock(&usb_bus_list_lock);
 863         list_del (&bus->bus_list);
 864         mutex_unlock(&usb_bus_list_lock);
 865
 866         usb_notify_remove_bus(bus);
 867
 868         clear_bit (bus->busnum, busmap.busmap);
 869
 870         device_unregister(bus->dev);
 871 }
 872
 873 /**
 874  * register_root_hub - called by usb_add_hcd() to register a root hub
 875  * @hcd: host controller for this root hub
 876  *
 877  * This function registers the root hub with the USB subsystem.  It sets up
 878  * the device properly in the device tree and then calls usb_new_device()
 879  * to register the usb device.  It also assigns the root hub's USB address
 880  * (always 1).
 881  */
 882 static int register_root_hub(struct usb_hcd *hcd)
 883 {
 884         struct device *parent_dev = hcd->self.controller;
 885         struct usb_device *usb_dev = hcd->self.root_hub;
 886         const int devnum = 1;
 887         int retval;
 888
 889         usb_dev->devnum = devnum;
 890         usb_dev->bus->devnum_next = devnum + 1;
 891         memset (&usb_dev->bus->devmap.devicemap, 0,
 892                         sizeof usb_dev->bus->devmap.devicemap);
 893         set_bit (devnum, usb_dev->bus->devmap.devicemap);
 894         usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
 895
 896         mutex_lock(&usb_bus_list_lock);
 897
 898         usb_dev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
 899         retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
 900         if (retval != sizeof usb_dev->descriptor) {
 901                 mutex_unlock(&usb_bus_list_lock);
 902                 dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
 903                                 dev_name(&usb_dev->dev), retval);
 904                 return (retval < 0) ? retval : -EMSGSIZE;
 905         }
 906
 907         retval = usb_new_device (usb_dev);
 908         if (retval) {
 909                 dev_err (parent_dev, "can't register root hub for %s, %d\n",
 910                                 dev_name(&usb_dev->dev), retval);
 911         }
 912         mutex_unlock(&usb_bus_list_lock);
 913
 914         if (retval == 0) {
 915                 spin_lock_irq (&hcd_root_hub_lock);
 916                 hcd->rh_registered = 1;
 917                 spin_unlock_irq (&hcd_root_hub_lock);
 918
 919                 /* Did the HC die before the root hub was registered? */
 920                 if (hcd->state == HC_STATE_HALT)
 921                         usb_hc_died (hcd);      /* This time clean up */
 922         }
 923
 924         return retval;
 925 }
 926
 927
 928 /*-------------------------------------------------------------------------*/
 929
 930 /**
 931  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
 932  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
 933  * @is_input: true iff the transaction sends data to the host
 934  * @isoc: true for isochronous transactions, false for interrupt ones
 935  * @bytecount: how many bytes in the transaction.
 936  *
 937  * Returns approximate bus time in nanoseconds for a periodic transaction.
 938  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
 939  * scheduled in software, this function is only used for such scheduling.
 940  */
 941 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
 942 {
 943         unsigned long   tmp;
 944
 945         switch (speed) {
 946         case USB_SPEED_LOW:     /* INTR only */
 947                 if (is_input) {
 948                         tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
 949                         return (64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
 950                 } else {
 951                         tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
 952                         return (64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
 953                 }
 954         case USB_SPEED_FULL:    /* ISOC or INTR */
 955                 if (isoc) {
 956                         tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
 957                         return (((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp);
 958                 } else {
 959                         tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
 960                         return (9107L + BW_HOST_DELAY + tmp);
 961                 }
 962         case USB_SPEED_HIGH:    /* ISOC or INTR */
 963                 // FIXME adjust for input vs output
 964                 if (isoc)
 965                         tmp = HS_NSECS_ISO (bytecount);
 966                 else
 967                         tmp = HS_NSECS (bytecount);
 968                 return tmp;
 969         default:
 970                 pr_debug ("%s: bogus device speed!\n", usbcore_name);
 971                 return -1;
 972         }
 973 }
 974 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
 975
 976
 977 /*-------------------------------------------------------------------------*/
 978
 979 /*
 980  * Generic HC operations.
 981  */
 982
 983 /*-------------------------------------------------------------------------*/
 984
 985 /**
 986  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
 987  * @hcd: host controller to which @urb was submitted
 988  * @urb: URB being submitted
 989  *
 990  * Host controller drivers should call this routine in their enqueue()
 991  * method.  The HCD's private spinlock must be held and interrupts must
 992  * be disabled.  The actions carried out here are required for URB
 993  * submission, as well as for endpoint shutdown and for usb_kill_urb.
 994  *
 995  * Returns 0 for no error, otherwise a negative error code (in which case
 996  * the enqueue() method must fail).  If no error occurs but enqueue() fails
 997  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
 998  * the private spinlock and returning.
 999  */
1000 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1001 {
1002         int             rc = 0;
1003
1004         spin_lock(&hcd_urb_list_lock);
1005
1006         /* Check that the URB isn't being killed */
1007         if (unlikely(urb->reject)) {
1008                 rc = -EPERM;
1009                 goto done;
1010         }
1011
1012         if (unlikely(!urb->ep->enabled)) {
1013                 rc = -ENOENT;
1014                 goto done;
1015         }
1016
1017         if (unlikely(!urb->dev->can_submit)) {
1018                 rc = -EHOSTUNREACH;
1019                 goto done;
1020         }
1021
1022         /*
1023          * Check the host controller's state and add the URB to the
1024          * endpoint's queue.
1025          */
1026         switch (hcd->state) {
1027         case HC_STATE_RUNNING:
1028         case HC_STATE_RESUMING:
1029                 urb->unlinked = 0;
1030                 list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1031                 break;
1032         default:
1033                 rc = -ESHUTDOWN;
1034                 goto done;
1035         }
1036  done:
1037         spin_unlock(&hcd_urb_list_lock);
1038         return rc;
1039 }
1040 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1041
1042 /**
1043  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1044  * @hcd: host controller to which @urb was submitted
1045  * @urb: URB being checked for unlinkability
1046  * @status: error code to store in @urb if the unlink succeeds
1047  *
1048  * Host controller drivers should call this routine in their dequeue()
1049  * method.  The HCD's private spinlock must be held and interrupts must
1050  * be disabled.  The actions carried out here are required for making
1051  * sure than an unlink is valid.
1052  *
1053  * Returns 0 for no error, otherwise a negative error code (in which case
1054  * the dequeue() method must fail).  The possible error codes are:
1055  *
1056  *      -EIDRM: @urb was not submitted or has already completed.
1057  *              The completion function may not have been called yet.
1058  *
1059  *      -EBUSY: @urb has already been unlinked.
1060  */
1061 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1062                 int status)
1063 {
1064         struct list_head        *tmp;
1065
1066         /* insist the urb is still queued */
1067         list_for_each(tmp, &urb->ep->urb_list) {
1068                 if (tmp == &urb->urb_list)
1069                         break;
1070         }
1071         if (tmp != &urb->urb_list)
1072                 return -EIDRM;
1073
1074         /* Any status except -EINPROGRESS means something already started to
1075          * unlink this URB from the hardware.  So there's no more work to do.
1076          */
1077         if (urb->unlinked)
1078                 return -EBUSY;
1079         urb->unlinked = status;
1080
1081         /* IRQ setup can easily be broken so that USB controllers
1082          * never get completion IRQs ... maybe even the ones we need to
1083          * finish unlinking the initial failed usb_set_address()
1084          * or device descriptor fetch.
1085          */
1086         if (!test_bit(HCD_FLAG_SAW_IRQ, &hcd->flags) &&
1087                         !is_root_hub(urb->dev)) {
1088                 dev_warn(hcd->self.controller, "Unlink after no-IRQ?  "
1089                         "Controller is probably using the wrong IRQ.\n");
1090                 set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
1091         }
1092
1093         return 0;
1094 }
1095 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1096
1097 /**
1098  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1099  * @hcd: host controller to which @urb was submitted
1100  * @urb: URB being unlinked
1101  *
1102  * Host controller drivers should call this routine before calling
1103  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1104  * interrupts must be disabled.  The actions carried out here are required
1105  * for URB completion.
1106  */
1107 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1108 {
1109         /* clear all state linking urb to this dev (and hcd) */
1110         spin_lock(&hcd_urb_list_lock);
1111         list_del_init(&urb->urb_list);
1112         spin_unlock(&hcd_urb_list_lock);
1113 }
1114 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1115
1116 /*
1117  * Some usb host controllers can only perform dma using a small SRAM area.
1118  * The usb core itself is however optimized for host controllers that can dma
1119  * using regular system memory - like pci devices doing bus mastering.
1120  *
1121  * To support host controllers with limited dma capabilites we provide dma
1122  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1123  * For this to work properly the host controller code must first use the
1124  * function dma_declare_coherent_memory() to point out which memory area
1125  * that should be used for dma allocations.
1126  *
1127  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1128  * dma using dma_alloc_coherent() which in turn allocates from the memory
1129  * area pointed out with dma_declare_coherent_memory().
1130  *
1131  * So, to summarize...
1132  *
1133  * - We need "local" memory, canonical example being
1134  *   a small SRAM on a discrete controller being the
1135  *   only memory that the controller can read ...
1136  *   (a) "normal" kernel memory is no good, and
1137  *   (b) there's not enough to share
1138  *
1139  * - The only *portable* hook for such stuff in the
1140  *   DMA framework is dma_declare_coherent_memory()
1141  *
1142  * - So we use that, even though the primary requirement
1143  *   is that the memory be "local" (hence addressible
1144  *   by that device), not "coherent".
1145  *
1146  */
1147
1148 static int hcd_alloc_coherent(struct usb_bus *bus,
1149                               gfp_t mem_flags, dma_addr_t *dma_handle,
1150                               void **vaddr_handle, size_t size,
1151                               enum dma_data_direction dir)
1152 {
1153         unsigned char *vaddr;
1154
1155         vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1156                                  mem_flags, dma_handle);
1157         if (!vaddr)
1158                 return -ENOMEM;
1159
1160         /*
1161          * Store the virtual address of the buffer at the end
1162          * of the allocated dma buffer. The size of the buffer
1163          * may be uneven so use unaligned functions instead
1164          * of just rounding up. It makes sense to optimize for
1165          * memory footprint over access speed since the amount
1166          * of memory available for dma may be limited.
1167          */
1168         put_unaligned((unsigned long)*vaddr_handle,
1169                       (unsigned long *)(vaddr + size));
1170
1171         if (dir == DMA_TO_DEVICE)
1172                 memcpy(vaddr, *vaddr_handle, size);
1173
1174         *vaddr_handle = vaddr;
1175         return 0;
1176 }
1177
1178 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1179                               void **vaddr_handle, size_t size,
1180                               enum dma_data_direction dir)
1181 {
1182         unsigned char *vaddr = *vaddr_handle;
1183
1184         vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1185
1186         if (dir == DMA_FROM_DEVICE)
1187                 memcpy(vaddr, *vaddr_handle, size);
1188
1189         hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1190
1191         *vaddr_handle = vaddr;
1192         *dma_handle = 0;
1193 }
1194
1195 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1196                            gfp_t mem_flags)
1197 {
1198         enum dma_data_direction dir;
1199         int ret = 0;
1200
1201         /* Map the URB's buffers for DMA access.
1202          * Lower level HCD code should use *_dma exclusively,
1203          * unless it uses pio or talks to another transport.
1204          */
1205         if (is_root_hub(urb->dev))
1206                 return 0;
1207
1208         if (usb_endpoint_xfer_control(&urb->ep->desc)
1209             && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) {
1210                 if (hcd->self.uses_dma)
1211                         urb->setup_dma = dma_map_single(
1212                                         hcd->self.controller,
1213                                         urb->setup_packet,
1214                                         sizeof(struct usb_ctrlrequest),
1215                                         DMA_TO_DEVICE);
1216                 else if (hcd->driver->flags & HCD_LOCAL_MEM)
1217                         ret = hcd_alloc_coherent(
1218                                         urb->dev->bus, mem_flags,
1219                                         &urb->setup_dma,
1220                                         (void **)&urb->setup_packet,
1221                                         sizeof(struct usb_ctrlrequest),
1222                                         DMA_TO_DEVICE);
1223         }
1224
1225         dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1226         if (ret == 0 && urb->transfer_buffer_length != 0
1227             && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1228                 if (hcd->self.uses_dma)
1229                         urb->transfer_dma = dma_map_single (
1230                                         hcd->self.controller,
1231                                         urb->transfer_buffer,
1232                                         urb->transfer_buffer_length,
1233                                         dir);
1234                 else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1235                         ret = hcd_alloc_coherent(
1236                                         urb->dev->bus, mem_flags,
1237                                         &urb->transfer_dma,
1238                                         &urb->transfer_buffer,
1239                                         urb->transfer_buffer_length,
1240                                         dir);
1241
1242                         if (ret && usb_endpoint_xfer_control(&urb->ep->desc)
1243                             && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP))
1244                                 hcd_free_coherent(urb->dev->bus,
1245                                         &urb->setup_dma,
1246                                         (void **)&urb->setup_packet,
1247                                         sizeof(struct usb_ctrlrequest),
1248                                         DMA_TO_DEVICE);
1249                 }
1250         }
1251         return ret;
1252 }
1253
1254 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1255 {
1256         enum dma_data_direction dir;
1257
1258         if (is_root_hub(urb->dev))
1259                 return;
1260
1261         if (usb_endpoint_xfer_control(&urb->ep->desc)
1262             && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) {
1263                 if (hcd->self.uses_dma)
1264                         dma_unmap_single(hcd->self.controller, urb->setup_dma,
1265                                         sizeof(struct usb_ctrlrequest),
1266                                         DMA_TO_DEVICE);
1267                 else if (hcd->driver->flags & HCD_LOCAL_MEM)
1268                         hcd_free_coherent(urb->dev->bus, &urb->setup_dma,
1269                                         (void **)&urb->setup_packet,
1270                                         sizeof(struct usb_ctrlrequest),
1271                                         DMA_TO_DEVICE);
1272         }
1273
1274         dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1275         if (urb->transfer_buffer_length != 0
1276             && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1277                 if (hcd->self.uses_dma)
1278                         dma_unmap_single(hcd->self.controller,
1279                                         urb->transfer_dma,
1280                                         urb->transfer_buffer_length,
1281                                         dir);
1282                 else if (hcd->driver->flags & HCD_LOCAL_MEM)
1283                         hcd_free_coherent(urb->dev->bus, &urb->transfer_dma,
1284                                         &urb->transfer_buffer,
1285                                         urb->transfer_buffer_length,
1286                                         dir);
1287         }
1288 }
1289
1290 /*-------------------------------------------------------------------------*/
1291
1292 /* may be called in any context with a valid urb->dev usecount
1293  * caller surrenders "ownership" of urb
1294  * expects usb_submit_urb() to have sanity checked and conditioned all
1295  * inputs in the urb
1296  */
1297 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1298 {
1299         int                     status;
1300         struct usb_hcd          *hcd = bus_to_hcd(urb->dev->bus);
1301
1302         /* increment urb's reference count as part of giving it to the HCD
1303          * (which will control it).  HCD guarantees that it either returns
1304          * an error or calls giveback(), but not both.
1305          */
1306         usb_get_urb(urb);
1307         atomic_inc(&urb->use_count);
1308         atomic_inc(&urb->dev->urbnum);
1309         usbmon_urb_submit(&hcd->self, urb);
1310
1311         /* NOTE requirements on root-hub callers (usbfs and the hub
1312          * driver, for now):  URBs' urb->transfer_buffer must be
1313          * valid and usb_buffer_{sync,unmap}() not be needed, since
1314          * they could clobber root hub response data.  Also, control
1315          * URBs must be submitted in process context with interrupts
1316          * enabled.
1317          */
1318         status = map_urb_for_dma(hcd, urb, mem_flags);
1319         if (unlikely(status)) {
1320                 usbmon_urb_submit_error(&hcd->self, urb, status);
1321                 goto error;
1322         }
1323
1324         if (is_root_hub(urb->dev))
1325                 status = rh_urb_enqueue(hcd, urb);
1326         else
1327                 status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1328
1329         if (unlikely(status)) {
1330                 usbmon_urb_submit_error(&hcd->self, urb, status);
1331                 unmap_urb_for_dma(hcd, urb);
1332  error:
1333                 urb->hcpriv = NULL;
1334                 INIT_LIST_HEAD(&urb->urb_list);
1335                 atomic_dec(&urb->use_count);
1336                 atomic_dec(&urb->dev->urbnum);
1337                 if (urb->reject)
1338                         wake_up(&usb_kill_urb_queue);
1339                 usb_put_urb(urb);
1340         }
1341         return status;
1342 }
1343
1344 /*-------------------------------------------------------------------------*/
1345
1346 /* this makes the hcd giveback() the urb more quickly, by kicking it
1347  * off hardware queues (which may take a while) and returning it as
1348  * soon as practical.  we've already set up the urb's return status,
1349  * but we can't know if the callback completed already.
1350  */
1351 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1352 {
1353         int             value;
1354
1355         if (is_root_hub(urb->dev))
1356                 value = usb_rh_urb_dequeue(hcd, urb, status);
1357         else {
1358
1359                 /* The only reason an HCD might fail this call is if
1360                  * it has not yet fully queued the urb to begin with.
1361                  * Such failures should be harmless. */
1362                 value = hcd->driver->urb_dequeue(hcd, urb, status);
1363         }
1364         return value;
1365 }
1366
1367 /*
1368  * called in any context
1369  *
1370  * caller guarantees urb won't be recycled till both unlink()
1371  * and the urb's completion function return
1372  */
1373 int usb_hcd_unlink_urb (struct urb *urb, int status)
1374 {
1375         struct usb_hcd          *hcd;
1376         int                     retval;
1377
1378         hcd = bus_to_hcd(urb->dev->bus);
1379         retval = unlink1(hcd, urb, status);
1380
1381         if (retval == 0)
1382                 retval = -EINPROGRESS;
1383         else if (retval != -EIDRM && retval != -EBUSY)
1384                 dev_dbg(&urb->dev->dev, "hcd_unlink_urb %p fail %d\n",
1385                                 urb, retval);
1386         return retval;
1387 }
1388
1389 /*-------------------------------------------------------------------------*/
1390
1391 /**
1392  * usb_hcd_giveback_urb - return URB from HCD to device driver
1393  * @hcd: host controller returning the URB
1394  * @urb: urb being returned to the USB device driver.
1395  * @status: completion status code for the URB.
1396  * Context: in_interrupt()
1397  *
1398  * This hands the URB from HCD to its USB device driver, using its
1399  * completion function.  The HCD has freed all per-urb resources
1400  * (and is done using urb->hcpriv).  It also released all HCD locks;
1401  * the device driver won't cause problems if it frees, modifies,
1402  * or resubmits this URB.
1403  *
1404  * If @urb was unlinked, the value of @status will be overridden by
1405  * @urb->unlinked.  Erroneous short transfers are detected in case
1406  * the HCD hasn't checked for them.
1407  */
1408 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1409 {
1410         urb->hcpriv = NULL;
1411         if (unlikely(urb->unlinked))
1412                 status = urb->unlinked;
1413         else if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1414                         urb->actual_length < urb->transfer_buffer_length &&
1415                         !status))
1416                 status = -EREMOTEIO;
1417
1418         unmap_urb_for_dma(hcd, urb);
1419         usbmon_urb_complete(&hcd->self, urb, status);
1420         usb_unanchor_urb(urb);
1421
1422         /* pass ownership to the completion handler */
1423         urb->status = status;
1424         urb->complete (urb);
1425         atomic_dec (&urb->use_count);
1426         if (unlikely (urb->reject))
1427                 wake_up (&usb_kill_urb_queue);
1428         usb_put_urb (urb);
1429 }
1430 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1431
1432 /*-------------------------------------------------------------------------*/
1433
1434 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1435  * queue to drain completely.  The caller must first insure that no more
1436  * URBs can be submitted for this endpoint.
1437  */
1438 void usb_hcd_flush_endpoint(struct usb_device *udev,
1439                 struct usb_host_endpoint *ep)
1440 {
1441         struct usb_hcd          *hcd;
1442         struct urb              *urb;
1443
1444         if (!ep)
1445                 return;
1446         might_sleep();
1447         hcd = bus_to_hcd(udev->bus);
1448
1449         /* No more submits can occur */
1450         spin_lock_irq(&hcd_urb_list_lock);
1451 rescan:
1452         list_for_each_entry (urb, &ep->urb_list, urb_list) {
1453                 int     is_in;
1454
1455                 if (urb->unlinked)
1456                         continue;
1457                 usb_get_urb (urb);
1458                 is_in = usb_urb_dir_in(urb);
1459                 spin_unlock(&hcd_urb_list_lock);
1460
1461                 /* kick hcd */
1462                 unlink1(hcd, urb, -ESHUTDOWN);
1463                 dev_dbg (hcd->self.controller,
1464                         "shutdown urb %p ep%d%s%s\n",
1465                         urb, usb_endpoint_num(&ep->desc),
1466                         is_in ? "in" : "out",
1467                         ({      char *s;
1468
1469                                  switch (usb_endpoint_type(&ep->desc)) {
1470                                  case USB_ENDPOINT_XFER_CONTROL:
1471                                         s = ""; break;
1472                                  case USB_ENDPOINT_XFER_BULK:
1473                                         s = "-bulk"; break;
1474                                  case USB_ENDPOINT_XFER_INT:
1475                                         s = "-intr"; break;
1476                                  default:
1477                                         s = "-iso"; break;
1478                                 };
1479                                 s;
1480                         }));
1481                 usb_put_urb (urb);
1482
1483                 /* list contents may have changed */
1484                 spin_lock(&hcd_urb_list_lock);
1485                 goto rescan;
1486         }
1487         spin_unlock_irq(&hcd_urb_list_lock);
1488
1489         /* Wait until the endpoint queue is completely empty */
1490         while (!list_empty (&ep->urb_list)) {
1491                 spin_lock_irq(&hcd_urb_list_lock);
1492
1493                 /* The list may have changed while we acquired the spinlock */
1494                 urb = NULL;
1495                 if (!list_empty (&ep->urb_list)) {
1496                         urb = list_entry (ep->urb_list.prev, struct urb,
1497                                         urb_list);
1498                         usb_get_urb (urb);
1499                 }
1500                 spin_unlock_irq(&hcd_urb_list_lock);
1501
1502                 if (urb) {
1503                         usb_kill_urb (urb);
1504                         usb_put_urb (urb);
1505                 }
1506         }
1507 }
1508
1509 /* Disables the endpoint: synchronizes with the hcd to make sure all
1510  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1511  * have been called previously.  Use for set_configuration, set_interface,
1512  * driver removal, physical disconnect.
1513  *
1514  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1515  * type, maxpacket size, toggle, halt status, and scheduling.
1516  */
1517 void usb_hcd_disable_endpoint(struct usb_device *udev,
1518                 struct usb_host_endpoint *ep)
1519 {
1520         struct usb_hcd          *hcd;
1521
1522         might_sleep();
1523         hcd = bus_to_hcd(udev->bus);
1524         if (hcd->driver->endpoint_disable)
1525                 hcd->driver->endpoint_disable(hcd, ep);
1526 }
1527
1528 /*-------------------------------------------------------------------------*/
1529
1530 /* called in any context */
1531 int usb_hcd_get_frame_number (struct usb_device *udev)
1532 {
1533         struct usb_hcd  *hcd = bus_to_hcd(udev->bus);
1534
1535         if (!HC_IS_RUNNING (hcd->state))
1536                 return -ESHUTDOWN;
1537         return hcd->driver->get_frame_number (hcd);
1538 }
1539
1540 /*-------------------------------------------------------------------------*/
1541
1542 #ifdef  CONFIG_PM
1543
1544 int hcd_bus_suspend(struct usb_device *rhdev)
1545 {
1546         struct usb_hcd  *hcd = container_of(rhdev->bus, struct usb_hcd, self);
1547         int             status;
1548         int             old_state = hcd->state;
1549
1550         dev_dbg(&rhdev->dev, "bus %s%s\n",
1551                         rhdev->auto_pm ? "auto-" : "", "suspend");
1552         if (!hcd->driver->bus_suspend) {
1553                 status = -ENOENT;
1554         } else {
1555                 hcd->state = HC_STATE_QUIESCING;
1556                 status = hcd->driver->bus_suspend(hcd);
1557         }
1558         if (status == 0) {
1559                 usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
1560                 hcd->state = HC_STATE_SUSPENDED;
1561         } else {
1562                 hcd->state = old_state;
1563                 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
1564                                 "suspend", status);
1565         }
1566         return status;
1567 }
1568
1569 int hcd_bus_resume(struct usb_device *rhdev)
1570 {
1571         struct usb_hcd  *hcd = container_of(rhdev->bus, struct usb_hcd, self);
1572         int             status;
1573         int             old_state = hcd->state;
1574
1575         dev_dbg(&rhdev->dev, "usb %s%s\n",
1576                         rhdev->auto_pm ? "auto-" : "", "resume");
1577         if (!hcd->driver->bus_resume)
1578                 return -ENOENT;
1579         if (hcd->state == HC_STATE_RUNNING)
1580                 return 0;
1581
1582         hcd->state = HC_STATE_RESUMING;
1583         status = hcd->driver->bus_resume(hcd);
1584         if (status == 0) {
1585                 /* TRSMRCY = 10 msec */
1586                 msleep(10);
1587                 usb_set_device_state(rhdev, rhdev->actconfig
1588                                 ? USB_STATE_CONFIGURED
1589                                 : USB_STATE_ADDRESS);
1590                 hcd->state = HC_STATE_RUNNING;
1591         } else {
1592                 hcd->state = old_state;
1593                 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
1594                                 "resume", status);
1595                 if (status != -ESHUTDOWN)
1596                         usb_hc_died(hcd);
1597         }
1598         return status;
1599 }
1600
1601 /* Workqueue routine for root-hub remote wakeup */
1602 static void hcd_resume_work(struct work_struct *work)
1603 {
1604         struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
1605         struct usb_device *udev = hcd->self.root_hub;
1606
1607         usb_lock_device(udev);
1608         usb_mark_last_busy(udev);
1609         usb_external_resume_device(udev);
1610         usb_unlock_device(udev);
1611 }
1612
1613 /**
1614  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
1615  * @hcd: host controller for this root hub
1616  *
1617  * The USB host controller calls this function when its root hub is
1618  * suspended (with the remote wakeup feature enabled) and a remote
1619  * wakeup request is received.  The routine submits a workqueue request
1620  * to resume the root hub (that is, manage its downstream ports again).
1621  */
1622 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
1623 {
1624         unsigned long flags;
1625
1626         spin_lock_irqsave (&hcd_root_hub_lock, flags);
1627         if (hcd->rh_registered)
1628                 queue_work(ksuspend_usb_wq, &hcd->wakeup_work);
1629         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
1630 }
1631 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
1632
1633 #endif
1634
1635 /*-------------------------------------------------------------------------*/
1636
1637 #ifdef  CONFIG_USB_OTG
1638
1639 /**
1640  * usb_bus_start_enum - start immediate enumeration (for OTG)
1641  * @bus: the bus (must use hcd framework)
1642  * @port_num: 1-based number of port; usually bus->otg_port
1643  * Context: in_interrupt()
1644  *
1645  * Starts enumeration, with an immediate reset followed later by
1646  * khubd identifying and possibly configuring the device.
1647  * This is needed by OTG controller drivers, where it helps meet
1648  * HNP protocol timing requirements for starting a port reset.
1649  */
1650 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
1651 {
1652         struct usb_hcd          *hcd;
1653         int                     status = -EOPNOTSUPP;
1654
1655         /* NOTE: since HNP can't start by grabbing the bus's address0_sem,
1656          * boards with root hubs hooked up to internal devices (instead of
1657          * just the OTG port) may need more attention to resetting...
1658          */
1659         hcd = container_of (bus, struct usb_hcd, self);
1660         if (port_num && hcd->driver->start_port_reset)
1661                 status = hcd->driver->start_port_reset(hcd, port_num);
1662
1663         /* run khubd shortly after (first) root port reset finishes;
1664          * it may issue others, until at least 50 msecs have passed.
1665          */
1666         if (status == 0)
1667                 mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
1668         return status;
1669 }
1670 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
1671
1672 #endif
1673
1674 /*-------------------------------------------------------------------------*/
1675
1676 /**
1677  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
1678  * @irq: the IRQ being raised
1679  * @__hcd: pointer to the HCD whose IRQ is being signaled
1680  *
1681  * If the controller isn't HALTed, calls the driver's irq handler.
1682  * Checks whether the controller is now dead.
1683  */
1684 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
1685 {
1686         struct usb_hcd          *hcd = __hcd;
1687         unsigned long           flags;
1688         irqreturn_t             rc;
1689
1690         /* IRQF_DISABLED doesn't work correctly with shared IRQs
1691          * when the first handler doesn't use it.  So let's just
1692          * assume it's never used.
1693          */
1694         local_irq_save(flags);
1695
1696         if (unlikely(hcd->state == HC_STATE_HALT ||
1697                      !test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))) {
1698                 rc = IRQ_NONE;
1699         } else if (hcd->driver->irq(hcd) == IRQ_NONE) {
1700                 rc = IRQ_NONE;
1701         } else {
1702                 set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
1703
1704                 if (unlikely(hcd->state == HC_STATE_HALT))
1705                         usb_hc_died(hcd);
1706                 rc = IRQ_HANDLED;
1707         }
1708
1709         local_irq_restore(flags);
1710         return rc;
1711 }
1712
1713 /*-------------------------------------------------------------------------*/
1714
1715 /**
1716  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
1717  * @hcd: pointer to the HCD representing the controller
1718  *
1719  * This is called by bus glue to report a USB host controller that died
1720  * while operations may still have been pending.  It's called automatically
1721  * by the PCI glue, so only glue for non-PCI busses should need to call it.
1722  */
1723 void usb_hc_died (struct usb_hcd *hcd)
1724 {
1725         unsigned long flags;
1726
1727         dev_err (hcd->self.controller, "HC died; cleaning up\n");
1728
1729         spin_lock_irqsave (&hcd_root_hub_lock, flags);
1730         if (hcd->rh_registered) {
1731                 hcd->poll_rh = 0;
1732
1733                 /* make khubd clean up old urbs and devices */
1734                 usb_set_device_state (hcd->self.root_hub,
1735                                 USB_STATE_NOTATTACHED);
1736                 usb_kick_khubd (hcd->self.root_hub);
1737         }
1738         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
1739 }
1740 EXPORT_SYMBOL_GPL (usb_hc_died);
1741
1742 /*-------------------------------------------------------------------------*/
1743
1744 /**
1745  * usb_create_hcd - create and initialize an HCD structure
1746  * @driver: HC driver that will use this hcd
1747  * @dev: device for this HC, stored in hcd->self.controller
1748  * @bus_name: value to store in hcd->self.bus_name
1749  * Context: !in_interrupt()
1750  *
1751  * Allocate a struct usb_hcd, with extra space at the end for the
1752  * HC driver's private data.  Initialize the generic members of the
1753  * hcd structure.
1754  *
1755  * If memory is unavailable, returns NULL.
1756  */
1757 struct usb_hcd *usb_create_hcd (const struct hc_driver *driver,
1758                 struct device *dev, const char *bus_name)
1759 {
1760         struct usb_hcd *hcd;
1761
1762         hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
1763         if (!hcd) {
1764                 dev_dbg (dev, "hcd alloc failed\n");
1765                 return NULL;
1766         }
1767         dev_set_drvdata(dev, hcd);
1768         kref_init(&hcd->kref);
1769
1770         usb_bus_init(&hcd->self);
1771         hcd->self.controller = dev;
1772         hcd->self.bus_name = bus_name;
1773         hcd->self.uses_dma = (dev->dma_mask != NULL);
1774
1775         init_timer(&hcd->rh_timer);
1776         hcd->rh_timer.function = rh_timer_func;
1777         hcd->rh_timer.data = (unsigned long) hcd;
1778 #ifdef CONFIG_PM
1779         INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
1780 #endif
1781
1782         hcd->driver = driver;
1783         hcd->product_desc = (driver->product_desc) ? driver->product_desc :
1784                         "USB Host Controller";
1785         return hcd;
1786 }
1787 EXPORT_SYMBOL_GPL(usb_create_hcd);
1788
1789 static void hcd_release (struct kref *kref)
1790 {
1791         struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
1792
1793         kfree(hcd);
1794 }
1795
1796 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
1797 {
1798         if (hcd)
1799                 kref_get (&hcd->kref);
1800         return hcd;
1801 }
1802 EXPORT_SYMBOL_GPL(usb_get_hcd);
1803
1804 void usb_put_hcd (struct usb_hcd *hcd)
1805 {
1806         if (hcd)
1807                 kref_put (&hcd->kref, hcd_release);
1808 }
1809 EXPORT_SYMBOL_GPL(usb_put_hcd);
1810
1811 /**
1812  * usb_add_hcd - finish generic HCD structure initialization and register
1813  * @hcd: the usb_hcd structure to initialize
1814  * @irqnum: Interrupt line to allocate
1815  * @irqflags: Interrupt type flags
1816  *
1817  * Finish the remaining parts of generic HCD initialization: allocate the
1818  * buffers of consistent memory, register the bus, request the IRQ line,
1819  * and call the driver's reset() and start() routines.
1820  */
1821 int usb_add_hcd(struct usb_hcd *hcd,
1822                 unsigned int irqnum, unsigned long irqflags)
1823 {
1824         int retval;
1825         struct usb_device *rhdev;
1826
1827         dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
1828
1829         hcd->authorized_default = hcd->wireless? 0 : 1;
1830         set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
1831
1832         /* HC is in reset state, but accessible.  Now do the one-time init,
1833          * bottom up so that hcds can customize the root hubs before khubd
1834          * starts talking to them.  (Note, bus id is assigned early too.)
1835          */
1836         if ((retval = hcd_buffer_create(hcd)) != 0) {
1837                 dev_dbg(hcd->self.controller, "pool alloc failed\n");
1838                 return retval;
1839         }
1840
1841         if ((retval = usb_register_bus(&hcd->self)) < 0)
1842                 goto err_register_bus;
1843
1844         if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
1845                 dev_err(hcd->self.controller, "unable to allocate root hub\n");
1846                 retval = -ENOMEM;
1847                 goto err_allocate_root_hub;
1848         }
1849         rhdev->speed = (hcd->driver->flags & HCD_USB2) ? USB_SPEED_HIGH :
1850                         USB_SPEED_FULL;
1851         hcd->self.root_hub = rhdev;
1852
1853         /* wakeup flag init defaults to "everything works" for root hubs,
1854          * but drivers can override it in reset() if needed, along with
1855          * recording the overall controller's system wakeup capability.
1856          */
1857         device_init_wakeup(&rhdev->dev, 1);
1858
1859         /* "reset" is misnamed; its role is now one-time init. the controller
1860          * should already have been reset (and boot firmware kicked off etc).
1861          */
1862         if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
1863                 dev_err(hcd->self.controller, "can't setup\n");
1864                 goto err_hcd_driver_setup;
1865         }
1866
1867         /* NOTE: root hub and controller capabilities may not be the same */
1868         if (device_can_wakeup(hcd->self.controller)
1869                         && device_can_wakeup(&hcd->self.root_hub->dev))
1870                 dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
1871
1872         /* enable irqs just before we start the controller */
1873         if (hcd->driver->irq) {
1874
1875                 /* IRQF_DISABLED doesn't work as advertised when used together
1876                  * with IRQF_SHARED. As usb_hcd_irq() will always disable
1877                  * interrupts we can remove it here.
1878                  */
1879                 if (irqflags & IRQF_SHARED)
1880                         irqflags &= ~IRQF_DISABLED;
1881
1882                 snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
1883                                 hcd->driver->description, hcd->self.busnum);
1884                 if ((retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
1885                                 hcd->irq_descr, hcd)) != 0) {
1886                         dev_err(hcd->self.controller,
1887                                         "request interrupt %d failed\n", irqnum);
1888                         goto err_request_irq;
1889                 }
1890                 hcd->irq = irqnum;
1891                 dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
1892                                 (hcd->driver->flags & HCD_MEMORY) ?
1893                                         "io mem" : "io base",
1894                                         (unsigned long long)hcd->rsrc_start);
1895         } else {
1896                 hcd->irq = -1;
1897                 if (hcd->rsrc_start)
1898                         dev_info(hcd->self.controller, "%s 0x%08llx\n",
1899                                         (hcd->driver->flags & HCD_MEMORY) ?
1900                                         "io mem" : "io base",
1901                                         (unsigned long long)hcd->rsrc_start);
1902         }
1903
1904         if ((retval = hcd->driver->start(hcd)) < 0) {
1905                 dev_err(hcd->self.controller, "startup error %d\n", retval);
1906                 goto err_hcd_driver_start;
1907         }
1908
1909         /* starting here, usbcore will pay attention to this root hub */
1910         rhdev->bus_mA = min(500u, hcd->power_budget);
1911         if ((retval = register_root_hub(hcd)) != 0)
1912                 goto err_register_root_hub;
1913
1914         retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
1915         if (retval < 0) {
1916                 printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
1917                        retval);
1918                 goto error_create_attr_group;
1919         }
1920         if (hcd->uses_new_polling && hcd->poll_rh)
1921                 usb_hcd_poll_rh_status(hcd);
1922         return retval;
1923
1924 error_create_attr_group:
1925         mutex_lock(&usb_bus_list_lock);
1926         usb_disconnect(&hcd->self.root_hub);
1927         mutex_unlock(&usb_bus_list_lock);
1928 err_register_root_hub:
1929         hcd->driver->stop(hcd);
1930 err_hcd_driver_start:
1931         if (hcd->irq >= 0)
1932                 free_irq(irqnum, hcd);
1933 err_request_irq:
1934 err_hcd_driver_setup:
1935         hcd->self.root_hub = NULL;
1936         usb_put_dev(rhdev);
1937 err_allocate_root_hub:
1938         usb_deregister_bus(&hcd->self);
1939 err_register_bus:
1940         hcd_buffer_destroy(hcd);
1941         return retval;
1942 }
1943 EXPORT_SYMBOL_GPL(usb_add_hcd);
1944
1945 /**
1946  * usb_remove_hcd - shutdown processing for generic HCDs
1947  * @hcd: the usb_hcd structure to remove
1948  * Context: !in_interrupt()
1949  *
1950  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
1951  * invoking the HCD's stop() method.
1952  */
1953 void usb_remove_hcd(struct usb_hcd *hcd)
1954 {
1955         dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
1956
1957         if (HC_IS_RUNNING (hcd->state))
1958                 hcd->state = HC_STATE_QUIESCING;
1959
1960         dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
1961         spin_lock_irq (&hcd_root_hub_lock);
1962         hcd->rh_registered = 0;
1963         spin_unlock_irq (&hcd_root_hub_lock);
1964
1965 #ifdef CONFIG_PM
1966         cancel_work_sync(&hcd->wakeup_work);
1967 #endif
1968
1969         sysfs_remove_group(&hcd->self.root_hub->dev.kobj, &usb_bus_attr_group);
1970         mutex_lock(&usb_bus_list_lock);
1971         usb_disconnect(&hcd->self.root_hub);
1972         mutex_unlock(&usb_bus_list_lock);
1973
1974         hcd->driver->stop(hcd);
1975         hcd->state = HC_STATE_HALT;
1976
1977         hcd->poll_rh = 0;
1978         del_timer_sync(&hcd->rh_timer);
1979
1980         if (hcd->irq >= 0)
1981                 free_irq(hcd->irq, hcd);
1982         usb_deregister_bus(&hcd->self);
1983         hcd_buffer_destroy(hcd);
1984 }
1985 EXPORT_SYMBOL_GPL(usb_remove_hcd);
1986
1987 void
1988 usb_hcd_platform_shutdown(struct platform_device* dev)
1989 {
1990         struct usb_hcd *hcd = platform_get_drvdata(dev);
1991
1992         if (hcd->driver->shutdown)
1993                 hcd->driver->shutdown(hcd);
1994 }
1995 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
1996
1997 /*-------------------------------------------------------------------------*/
1998
1999 #if defined(CONFIG_USB_MON)
2000
2001 struct usb_mon_operations *mon_ops;
2002
2003 /*
2004  * The registration is unlocked.
2005  * We do it this way because we do not want to lock in hot paths.
2006  *
2007  * Notice that the code is minimally error-proof. Because usbmon needs
2008  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2009  */
2010
2011 int usb_mon_register (struct usb_mon_operations *ops)
2012 {
2013
2014         if (mon_ops)
2015                 return -EBUSY;
2016
2017         mon_ops = ops;
2018         mb();
2019         return 0;
2020 }
2021 EXPORT_SYMBOL_GPL (usb_mon_register);
2022
2023 void usb_mon_deregister (void)
2024 {
2025
2026         if (mon_ops == NULL) {
2027                 printk(KERN_ERR "USB: monitor was not registered\n");
2028                 return;
2029         }
2030         mon_ops = NULL;
2031         mb();
2032 }
2033 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2034
2035 #endif /* CONFIG_USB_MON */