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 #include <linux/pm_runtime.h>
  42
  43 #include <linux/usb.h>
  44 #include <linux/usb/hcd.h>
  45
  46 #include "usb.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 /* Keep track of which host controller drivers are loaded */
  85 unsigned long usb_hcds_loaded;
  86 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
  87
  88 /* host controllers we manage */
  89 LIST_HEAD (usb_bus_list);
  90 EXPORT_SYMBOL_GPL (usb_bus_list);
  91
  92 /* used when allocating bus numbers */
  93 #define USB_MAXBUS              64
  94 struct usb_busmap {
  95         unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))];
  96 };
  97 static struct usb_busmap busmap;
  98
  99 /* used when updating list of hcds */
 100 DEFINE_MUTEX(usb_bus_list_lock);        /* exported only for usbfs */
 101 EXPORT_SYMBOL_GPL (usb_bus_list_lock);
 102
 103 /* used for controlling access to virtual root hubs */
 104 static DEFINE_SPINLOCK(hcd_root_hub_lock);
 105
 106 /* used when updating an endpoint's URB list */
 107 static DEFINE_SPINLOCK(hcd_urb_list_lock);
 108
 109 /* used to protect against unlinking URBs after the device is gone */
 110 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
 111
 112 /* wait queue for synchronous unlinks */
 113 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
 114
 115 static inline int is_root_hub(struct usb_device *udev)
 116 {
 117         return (udev->parent == NULL);
 118 }
 119
 120 /*-------------------------------------------------------------------------*/
 121
 122 /*
 123  * Sharable chunks of root hub code.
 124  */
 125
 126 /*-------------------------------------------------------------------------*/
 127
 128 #define KERNEL_REL      ((LINUX_VERSION_CODE >> 16) & 0x0ff)
 129 #define KERNEL_VER      ((LINUX_VERSION_CODE >> 8) & 0x0ff)
 130
 131 /* usb 3.0 root hub device descriptor */
 132 static const u8 usb3_rh_dev_descriptor[18] = {
 133         0x12,       /*  __u8  bLength; */
 134         0x01,       /*  __u8  bDescriptorType; Device */
 135         0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
 136
 137         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 138         0x00,       /*  __u8  bDeviceSubClass; */
 139         0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
 140         0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
 141
 142         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation */
 143         0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
 144         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 145
 146         0x03,       /*  __u8  iManufacturer; */
 147         0x02,       /*  __u8  iProduct; */
 148         0x01,       /*  __u8  iSerialNumber; */
 149         0x01        /*  __u8  bNumConfigurations; */
 150 };
 151
 152 /* usb 2.0 root hub device descriptor */
 153 static const u8 usb2_rh_dev_descriptor [18] = {
 154         0x12,       /*  __u8  bLength; */
 155         0x01,       /*  __u8  bDescriptorType; Device */
 156         0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
 157
 158         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 159         0x00,       /*  __u8  bDeviceSubClass; */
 160         0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 161         0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 162
 163         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation */
 164         0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 165         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 166
 167         0x03,       /*  __u8  iManufacturer; */
 168         0x02,       /*  __u8  iProduct; */
 169         0x01,       /*  __u8  iSerialNumber; */
 170         0x01        /*  __u8  bNumConfigurations; */
 171 };
 172
 173 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
 174
 175 /* usb 1.1 root hub device descriptor */
 176 static const u8 usb11_rh_dev_descriptor [18] = {
 177         0x12,       /*  __u8  bLength; */
 178         0x01,       /*  __u8  bDescriptorType; Device */
 179         0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
 180
 181         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 182         0x00,       /*  __u8  bDeviceSubClass; */
 183         0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
 184         0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 185
 186         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation */
 187         0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
 188         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 189
 190         0x03,       /*  __u8  iManufacturer; */
 191         0x02,       /*  __u8  iProduct; */
 192         0x01,       /*  __u8  iSerialNumber; */
 193         0x01        /*  __u8  bNumConfigurations; */
 194 };
 195
 196
 197 /*-------------------------------------------------------------------------*/
 198
 199 /* Configuration descriptors for our root hubs */
 200
 201 static const u8 fs_rh_config_descriptor [] = {
 202
 203         /* one configuration */
 204         0x09,       /*  __u8  bLength; */
 205         0x02,       /*  __u8  bDescriptorType; Configuration */
 206         0x19, 0x00, /*  __le16 wTotalLength; */
 207         0x01,       /*  __u8  bNumInterfaces; (1) */
 208         0x01,       /*  __u8  bConfigurationValue; */
 209         0x00,       /*  __u8  iConfiguration; */
 210         0xc0,       /*  __u8  bmAttributes;
 211                                  Bit 7: must be set,
 212                                      6: Self-powered,
 213                                      5: Remote wakeup,
 214                                      4..0: resvd */
 215         0x00,       /*  __u8  MaxPower; */
 216
 217         /* USB 1.1:
 218          * USB 2.0, single TT organization (mandatory):
 219          *      one interface, protocol 0
 220          *
 221          * USB 2.0, multiple TT organization (optional):
 222          *      two interfaces, protocols 1 (like single TT)
 223          *      and 2 (multiple TT mode) ... config is
 224          *      sometimes settable
 225          *      NOT IMPLEMENTED
 226          */
 227
 228         /* one interface */
 229         0x09,       /*  __u8  if_bLength; */
 230         0x04,       /*  __u8  if_bDescriptorType; Interface */
 231         0x00,       /*  __u8  if_bInterfaceNumber; */
 232         0x00,       /*  __u8  if_bAlternateSetting; */
 233         0x01,       /*  __u8  if_bNumEndpoints; */
 234         0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 235         0x00,       /*  __u8  if_bInterfaceSubClass; */
 236         0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 237         0x00,       /*  __u8  if_iInterface; */
 238
 239         /* one endpoint (status change endpoint) */
 240         0x07,       /*  __u8  ep_bLength; */
 241         0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
 242         0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 243         0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 244         0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
 245         0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
 246 };
 247
 248 static const u8 hs_rh_config_descriptor [] = {
 249
 250         /* one configuration */
 251         0x09,       /*  __u8  bLength; */
 252         0x02,       /*  __u8  bDescriptorType; Configuration */
 253         0x19, 0x00, /*  __le16 wTotalLength; */
 254         0x01,       /*  __u8  bNumInterfaces; (1) */
 255         0x01,       /*  __u8  bConfigurationValue; */
 256         0x00,       /*  __u8  iConfiguration; */
 257         0xc0,       /*  __u8  bmAttributes;
 258                                  Bit 7: must be set,
 259                                      6: Self-powered,
 260                                      5: Remote wakeup,
 261                                      4..0: resvd */
 262         0x00,       /*  __u8  MaxPower; */
 263
 264         /* USB 1.1:
 265          * USB 2.0, single TT organization (mandatory):
 266          *      one interface, protocol 0
 267          *
 268          * USB 2.0, multiple TT organization (optional):
 269          *      two interfaces, protocols 1 (like single TT)
 270          *      and 2 (multiple TT mode) ... config is
 271          *      sometimes settable
 272          *      NOT IMPLEMENTED
 273          */
 274
 275         /* one interface */
 276         0x09,       /*  __u8  if_bLength; */
 277         0x04,       /*  __u8  if_bDescriptorType; Interface */
 278         0x00,       /*  __u8  if_bInterfaceNumber; */
 279         0x00,       /*  __u8  if_bAlternateSetting; */
 280         0x01,       /*  __u8  if_bNumEndpoints; */
 281         0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 282         0x00,       /*  __u8  if_bInterfaceSubClass; */
 283         0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 284         0x00,       /*  __u8  if_iInterface; */
 285
 286         /* one endpoint (status change endpoint) */
 287         0x07,       /*  __u8  ep_bLength; */
 288         0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
 289         0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 290         0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 291                     /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 292                      * see hub.c:hub_configure() for details. */
 293         (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 294         0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 295 };
 296
 297 static const u8 ss_rh_config_descriptor[] = {
 298         /* one configuration */
 299         0x09,       /*  __u8  bLength; */
 300         0x02,       /*  __u8  bDescriptorType; Configuration */
 301         0x19, 0x00, /*  __le16 wTotalLength; FIXME */
 302         0x01,       /*  __u8  bNumInterfaces; (1) */
 303         0x01,       /*  __u8  bConfigurationValue; */
 304         0x00,       /*  __u8  iConfiguration; */
 305         0xc0,       /*  __u8  bmAttributes;
 306                                  Bit 7: must be set,
 307                                      6: Self-powered,
 308                                      5: Remote wakeup,
 309                                      4..0: resvd */
 310         0x00,       /*  __u8  MaxPower; */
 311
 312         /* one interface */
 313         0x09,       /*  __u8  if_bLength; */
 314         0x04,       /*  __u8  if_bDescriptorType; Interface */
 315         0x00,       /*  __u8  if_bInterfaceNumber; */
 316         0x00,       /*  __u8  if_bAlternateSetting; */
 317         0x01,       /*  __u8  if_bNumEndpoints; */
 318         0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 319         0x00,       /*  __u8  if_bInterfaceSubClass; */
 320         0x00,       /*  __u8  if_bInterfaceProtocol; */
 321         0x00,       /*  __u8  if_iInterface; */
 322
 323         /* one endpoint (status change endpoint) */
 324         0x07,       /*  __u8  ep_bLength; */
 325         0x05,       /*  __u8  ep_bDescriptorType; Endpoint */
 326         0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 327         0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 328                     /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 329                      * see hub.c:hub_configure() for details. */
 330         (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 331         0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 332         /*
 333          * All 3.0 hubs should have an endpoint companion descriptor,
 334          * but we're ignoring that for now.  FIXME?
 335          */
 336 };
 337
 338 /*-------------------------------------------------------------------------*/
 339
 340 /**
 341  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
 342  * @s: Null-terminated ASCII (actually ISO-8859-1) string
 343  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
 344  * @len: Length (in bytes; may be odd) of descriptor buffer.
 345  *
 346  * The return value is the number of bytes filled in: 2 + 2*strlen(s) or
 347  * buflen, whichever is less.
 348  *
 349  * USB String descriptors can contain at most 126 characters; input
 350  * strings longer than that are truncated.
 351  */
 352 static unsigned
 353 ascii2desc(char const *s, u8 *buf, unsigned len)
 354 {
 355         unsigned n, t = 2 + 2*strlen(s);
 356
 357         if (t > 254)
 358                 t = 254;        /* Longest possible UTF string descriptor */
 359         if (len > t)
 360                 len = t;
 361
 362         t += USB_DT_STRING << 8;        /* Now t is first 16 bits to store */
 363
 364         n = len;
 365         while (n--) {
 366                 *buf++ = t;
 367                 if (!n--)
 368                         break;
 369                 *buf++ = t >> 8;
 370                 t = (unsigned char)*s++;
 371         }
 372         return len;
 373 }
 374
 375 /**
 376  * rh_string() - provides string descriptors for root hub
 377  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
 378  * @hcd: the host controller for this root hub
 379  * @data: buffer for output packet
 380  * @len: length of the provided buffer
 381  *
 382  * Produces either a manufacturer, product or serial number string for the
 383  * virtual root hub device.
 384  * Returns the number of bytes filled in: the length of the descriptor or
 385  * of the provided buffer, whichever is less.
 386  */
 387 static unsigned
 388 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
 389 {
 390         char buf[100];
 391         char const *s;
 392         static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
 393
 394         // language ids
 395         switch (id) {
 396         case 0:
 397                 /* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
 398                 /* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
 399                 if (len > 4)
 400                         len = 4;
 401                 memcpy(data, langids, len);
 402                 return len;
 403         case 1:
 404                 /* Serial number */
 405                 s = hcd->self.bus_name;
 406                 break;
 407         case 2:
 408                 /* Product name */
 409                 s = hcd->product_desc;
 410                 break;
 411         case 3:
 412                 /* Manufacturer */
 413                 snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
 414                         init_utsname()->release, hcd->driver->description);
 415                 s = buf;
 416                 break;
 417         default:
 418                 /* Can't happen; caller guarantees it */
 419                 return 0;
 420         }
 421
 422         return ascii2desc(s, data, len);
 423 }
 424
 425
 426 /* Root hub control transfers execute synchronously */
 427 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
 428 {
 429         struct usb_ctrlrequest *cmd;
 430         u16             typeReq, wValue, wIndex, wLength;
 431         u8              *ubuf = urb->transfer_buffer;
 432         u8              tbuf [sizeof (struct usb_hub_descriptor)]
 433                 __attribute__((aligned(4)));
 434         const u8        *bufp = tbuf;
 435         unsigned        len = 0;
 436         int             status;
 437         u8              patch_wakeup = 0;
 438         u8              patch_protocol = 0;
 439
 440         might_sleep();
 441
 442         spin_lock_irq(&hcd_root_hub_lock);
 443         status = usb_hcd_link_urb_to_ep(hcd, urb);
 444         spin_unlock_irq(&hcd_root_hub_lock);
 445         if (status)
 446                 return status;
 447         urb->hcpriv = hcd;      /* Indicate it's queued */
 448
 449         cmd = (struct usb_ctrlrequest *) urb->setup_packet;
 450         typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
 451         wValue   = le16_to_cpu (cmd->wValue);
 452         wIndex   = le16_to_cpu (cmd->wIndex);
 453         wLength  = le16_to_cpu (cmd->wLength);
 454
 455         if (wLength > urb->transfer_buffer_length)
 456                 goto error;
 457
 458         urb->actual_length = 0;
 459         switch (typeReq) {
 460
 461         /* DEVICE REQUESTS */
 462
 463         /* The root hub's remote wakeup enable bit is implemented using
 464          * driver model wakeup flags.  If this system supports wakeup
 465          * through USB, userspace may change the default "allow wakeup"
 466          * policy through sysfs or these calls.
 467          *
 468          * Most root hubs support wakeup from downstream devices, for
 469          * runtime power management (disabling USB clocks and reducing
 470          * VBUS power usage).  However, not all of them do so; silicon,
 471          * board, and BIOS bugs here are not uncommon, so these can't
 472          * be treated quite like external hubs.
 473          *
 474          * Likewise, not all root hubs will pass wakeup events upstream,
 475          * to wake up the whole system.  So don't assume root hub and
 476          * controller capabilities are identical.
 477          */
 478
 479         case DeviceRequest | USB_REQ_GET_STATUS:
 480                 tbuf [0] = (device_may_wakeup(&hcd->self.root_hub->dev)
 481                                         << USB_DEVICE_REMOTE_WAKEUP)
 482                                 | (1 << USB_DEVICE_SELF_POWERED);
 483                 tbuf [1] = 0;
 484                 len = 2;
 485                 break;
 486         case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
 487                 if (wValue == USB_DEVICE_REMOTE_WAKEUP)
 488                         device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
 489                 else
 490                         goto error;
 491                 break;
 492         case DeviceOutRequest | USB_REQ_SET_FEATURE:
 493                 if (device_can_wakeup(&hcd->self.root_hub->dev)
 494                                 && wValue == USB_DEVICE_REMOTE_WAKEUP)
 495                         device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
 496                 else
 497                         goto error;
 498                 break;
 499         case DeviceRequest | USB_REQ_GET_CONFIGURATION:
 500                 tbuf [0] = 1;
 501                 len = 1;
 502                         /* FALLTHROUGH */
 503         case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
 504                 break;
 505         case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 506                 switch (wValue & 0xff00) {
 507                 case USB_DT_DEVICE << 8:
 508                         switch (hcd->driver->flags & HCD_MASK) {
 509                         case HCD_USB3:
 510                                 bufp = usb3_rh_dev_descriptor;
 511                                 break;
 512                         case HCD_USB2:
 513                                 bufp = usb2_rh_dev_descriptor;
 514                                 break;
 515                         case HCD_USB11:
 516                                 bufp = usb11_rh_dev_descriptor;
 517                                 break;
 518                         default:
 519                                 goto error;
 520                         }
 521                         len = 18;
 522                         if (hcd->has_tt)
 523                                 patch_protocol = 1;
 524                         break;
 525                 case USB_DT_CONFIG << 8:
 526                         switch (hcd->driver->flags & HCD_MASK) {
 527                         case HCD_USB3:
 528                                 bufp = ss_rh_config_descriptor;
 529                                 len = sizeof ss_rh_config_descriptor;
 530                                 break;
 531                         case HCD_USB2:
 532                                 bufp = hs_rh_config_descriptor;
 533                                 len = sizeof hs_rh_config_descriptor;
 534                                 break;
 535                         case HCD_USB11:
 536                                 bufp = fs_rh_config_descriptor;
 537                                 len = sizeof fs_rh_config_descriptor;
 538                                 break;
 539                         default:
 540                                 goto error;
 541                         }
 542                         if (device_can_wakeup(&hcd->self.root_hub->dev))
 543                                 patch_wakeup = 1;
 544                         break;
 545                 case USB_DT_STRING << 8:
 546                         if ((wValue & 0xff) < 4)
 547                                 urb->actual_length = rh_string(wValue & 0xff,
 548                                                 hcd, ubuf, wLength);
 549                         else /* unsupported IDs --> "protocol stall" */
 550                                 goto error;
 551                         break;
 552                 default:
 553                         goto error;
 554                 }
 555                 break;
 556         case DeviceRequest | USB_REQ_GET_INTERFACE:
 557                 tbuf [0] = 0;
 558                 len = 1;
 559                         /* FALLTHROUGH */
 560         case DeviceOutRequest | USB_REQ_SET_INTERFACE:
 561                 break;
 562         case DeviceOutRequest | USB_REQ_SET_ADDRESS:
 563                 // wValue == urb->dev->devaddr
 564                 dev_dbg (hcd->self.controller, "root hub device address %d\n",
 565                         wValue);
 566                 break;
 567
 568         /* INTERFACE REQUESTS (no defined feature/status flags) */
 569
 570         /* ENDPOINT REQUESTS */
 571
 572         case EndpointRequest | USB_REQ_GET_STATUS:
 573                 // ENDPOINT_HALT flag
 574                 tbuf [0] = 0;
 575                 tbuf [1] = 0;
 576                 len = 2;
 577                         /* FALLTHROUGH */
 578         case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
 579         case EndpointOutRequest | USB_REQ_SET_FEATURE:
 580                 dev_dbg (hcd->self.controller, "no endpoint features yet\n");
 581                 break;
 582
 583         /* CLASS REQUESTS (and errors) */
 584
 585         default:
 586                 /* non-generic request */
 587                 switch (typeReq) {
 588                 case GetHubStatus:
 589                 case GetPortStatus:
 590                         len = 4;
 591                         break;
 592                 case GetHubDescriptor:
 593                         len = sizeof (struct usb_hub_descriptor);
 594                         break;
 595                 }
 596                 status = hcd->driver->hub_control (hcd,
 597                         typeReq, wValue, wIndex,
 598                         tbuf, wLength);
 599                 break;
 600 error:
 601                 /* "protocol stall" on error */
 602                 status = -EPIPE;
 603         }
 604
 605         if (status) {
 606                 len = 0;
 607                 if (status != -EPIPE) {
 608                         dev_dbg (hcd->self.controller,
 609                                 "CTRL: TypeReq=0x%x val=0x%x "
 610                                 "idx=0x%x len=%d ==> %d\n",
 611                                 typeReq, wValue, wIndex,
 612                                 wLength, status);
 613                 }
 614         }
 615         if (len) {
 616                 if (urb->transfer_buffer_length < len)
 617                         len = urb->transfer_buffer_length;
 618                 urb->actual_length = len;
 619                 // always USB_DIR_IN, toward host
 620                 memcpy (ubuf, bufp, len);
 621
 622                 /* report whether RH hardware supports remote wakeup */
 623                 if (patch_wakeup &&
 624                                 len > offsetof (struct usb_config_descriptor,
 625                                                 bmAttributes))
 626                         ((struct usb_config_descriptor *)ubuf)->bmAttributes
 627                                 |= USB_CONFIG_ATT_WAKEUP;
 628
 629                 /* report whether RH hardware has an integrated TT */
 630                 if (patch_protocol &&
 631                                 len > offsetof(struct usb_device_descriptor,
 632                                                 bDeviceProtocol))
 633                         ((struct usb_device_descriptor *) ubuf)->
 634                                         bDeviceProtocol = 1;
 635         }
 636
 637         /* any errors get returned through the urb completion */
 638         spin_lock_irq(&hcd_root_hub_lock);
 639         usb_hcd_unlink_urb_from_ep(hcd, urb);
 640
 641         /* This peculiar use of spinlocks echoes what real HC drivers do.
 642          * Avoiding calls to local_irq_disable/enable makes the code
 643          * RT-friendly.
 644          */
 645         spin_unlock(&hcd_root_hub_lock);
 646         usb_hcd_giveback_urb(hcd, urb, status);
 647         spin_lock(&hcd_root_hub_lock);
 648
 649         spin_unlock_irq(&hcd_root_hub_lock);
 650         return 0;
 651 }
 652
 653 /*-------------------------------------------------------------------------*/
 654
 655 /*
 656  * Root Hub interrupt transfers are polled using a timer if the
 657  * driver requests it; otherwise the driver is responsible for
 658  * calling usb_hcd_poll_rh_status() when an event occurs.
 659  *
 660  * Completions are called in_interrupt(), but they may or may not
 661  * be in_irq().
 662  */
 663 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
 664 {
 665         struct urb      *urb;
 666         int             length;
 667         unsigned long   flags;
 668         char            buffer[6];      /* Any root hubs with > 31 ports? */
 669
 670         if (unlikely(!hcd->rh_pollable))
 671                 return;
 672         if (!hcd->uses_new_polling && !hcd->status_urb)
 673                 return;
 674
 675         length = hcd->driver->hub_status_data(hcd, buffer);
 676         if (length > 0) {
 677
 678                 /* try to complete the status urb */
 679                 spin_lock_irqsave(&hcd_root_hub_lock, flags);
 680                 urb = hcd->status_urb;
 681                 if (urb) {
 682                         clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 683                         hcd->status_urb = NULL;
 684                         urb->actual_length = length;
 685                         memcpy(urb->transfer_buffer, buffer, length);
 686
 687                         usb_hcd_unlink_urb_from_ep(hcd, urb);
 688                         spin_unlock(&hcd_root_hub_lock);
 689                         usb_hcd_giveback_urb(hcd, urb, 0);
 690                         spin_lock(&hcd_root_hub_lock);
 691                 } else {
 692                         length = 0;
 693                         set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 694                 }
 695                 spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 696         }
 697
 698         /* The USB 2.0 spec says 256 ms.  This is close enough and won't
 699          * exceed that limit if HZ is 100. The math is more clunky than
 700          * maybe expected, this is to make sure that all timers for USB devices
 701          * fire at the same time to give the CPU a break inbetween */
 702         if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
 703                         (length == 0 && hcd->status_urb != NULL))
 704                 mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 705 }
 706 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
 707
 708 /* timer callback */
 709 static void rh_timer_func (unsigned long _hcd)
 710 {
 711         usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
 712 }
 713
 714 /*-------------------------------------------------------------------------*/
 715
 716 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
 717 {
 718         int             retval;
 719         unsigned long   flags;
 720         unsigned        len = 1 + (urb->dev->maxchild / 8);
 721
 722         spin_lock_irqsave (&hcd_root_hub_lock, flags);
 723         if (hcd->status_urb || urb->transfer_buffer_length < len) {
 724                 dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
 725                 retval = -EINVAL;
 726                 goto done;
 727         }
 728
 729         retval = usb_hcd_link_urb_to_ep(hcd, urb);
 730         if (retval)
 731                 goto done;
 732
 733         hcd->status_urb = urb;
 734         urb->hcpriv = hcd;      /* indicate it's queued */
 735         if (!hcd->uses_new_polling)
 736                 mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 737
 738         /* If a status change has already occurred, report it ASAP */
 739         else if (HCD_POLL_PENDING(hcd))
 740                 mod_timer(&hcd->rh_timer, jiffies);
 741         retval = 0;
 742  done:
 743         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
 744         return retval;
 745 }
 746
 747 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
 748 {
 749         if (usb_endpoint_xfer_int(&urb->ep->desc))
 750                 return rh_queue_status (hcd, urb);
 751         if (usb_endpoint_xfer_control(&urb->ep->desc))
 752                 return rh_call_control (hcd, urb);
 753         return -EINVAL;
 754 }
 755
 756 /*-------------------------------------------------------------------------*/
 757
 758 /* Unlinks of root-hub control URBs are legal, but they don't do anything
 759  * since these URBs always execute synchronously.
 760  */
 761 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 762 {
 763         unsigned long   flags;
 764         int             rc;
 765
 766         spin_lock_irqsave(&hcd_root_hub_lock, flags);
 767         rc = usb_hcd_check_unlink_urb(hcd, urb, status);
 768         if (rc)
 769                 goto done;
 770
 771         if (usb_endpoint_num(&urb->ep->desc) == 0) {    /* Control URB */
 772                 ;       /* Do nothing */
 773
 774         } else {                                /* Status URB */
 775                 if (!hcd->uses_new_polling)
 776                         del_timer (&hcd->rh_timer);
 777                 if (urb == hcd->status_urb) {
 778                         hcd->status_urb = NULL;
 779                         usb_hcd_unlink_urb_from_ep(hcd, urb);
 780
 781                         spin_unlock(&hcd_root_hub_lock);
 782                         usb_hcd_giveback_urb(hcd, urb, status);
 783                         spin_lock(&hcd_root_hub_lock);
 784                 }
 785         }
 786  done:
 787         spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 788         return rc;
 789 }
 790
 791
 792
 793 /*
 794  * Show & store the current value of authorized_default
 795  */
 796 static ssize_t usb_host_authorized_default_show(struct device *dev,
 797                                                 struct device_attribute *attr,
 798                                                 char *buf)
 799 {
 800         struct usb_device *rh_usb_dev = to_usb_device(dev);
 801         struct usb_bus *usb_bus = rh_usb_dev->bus;
 802         struct usb_hcd *usb_hcd;
 803
 804         if (usb_bus == NULL)    /* FIXME: not sure if this case is possible */
 805                 return -ENODEV;
 806         usb_hcd = bus_to_hcd(usb_bus);
 807         return snprintf(buf, PAGE_SIZE, "%u\n", usb_hcd->authorized_default);
 808 }
 809
 810 static ssize_t usb_host_authorized_default_store(struct device *dev,
 811                                                  struct device_attribute *attr,
 812                                                  const char *buf, size_t size)
 813 {
 814         ssize_t result;
 815         unsigned val;
 816         struct usb_device *rh_usb_dev = to_usb_device(dev);
 817         struct usb_bus *usb_bus = rh_usb_dev->bus;
 818         struct usb_hcd *usb_hcd;
 819
 820         if (usb_bus == NULL)    /* FIXME: not sure if this case is possible */
 821                 return -ENODEV;
 822         usb_hcd = bus_to_hcd(usb_bus);
 823         result = sscanf(buf, "%u\n", &val);
 824         if (result == 1) {
 825                 usb_hcd->authorized_default = val? 1 : 0;
 826                 result = size;
 827         }
 828         else
 829                 result = -EINVAL;
 830         return result;
 831 }
 832
 833 static DEVICE_ATTR(authorized_default, 0644,
 834             usb_host_authorized_default_show,
 835             usb_host_authorized_default_store);
 836
 837
 838 /* Group all the USB bus attributes */
 839 static struct attribute *usb_bus_attrs[] = {
 840                 &dev_attr_authorized_default.attr,
 841                 NULL,
 842 };
 843
 844 static struct attribute_group usb_bus_attr_group = {
 845         .name = NULL,   /* we want them in the same directory */
 846         .attrs = usb_bus_attrs,
 847 };
 848
 849
 850
 851 /*-------------------------------------------------------------------------*/
 852
 853 /**
 854  * usb_bus_init - shared initialization code
 855  * @bus: the bus structure being initialized
 856  *
 857  * This code is used to initialize a usb_bus structure, memory for which is
 858  * separately managed.
 859  */
 860 static void usb_bus_init (struct usb_bus *bus)
 861 {
 862         memset (&bus->devmap, 0, sizeof(struct usb_devmap));
 863
 864         bus->devnum_next = 1;
 865
 866         bus->root_hub = NULL;
 867         bus->busnum = -1;
 868         bus->bandwidth_allocated = 0;
 869         bus->bandwidth_int_reqs  = 0;
 870         bus->bandwidth_isoc_reqs = 0;
 871
 872         INIT_LIST_HEAD (&bus->bus_list);
 873 }
 874
 875 /*-------------------------------------------------------------------------*/
 876
 877 /**
 878  * usb_register_bus - registers the USB host controller with the usb core
 879  * @bus: pointer to the bus to register
 880  * Context: !in_interrupt()
 881  *
 882  * Assigns a bus number, and links the controller into usbcore data
 883  * structures so that it can be seen by scanning the bus list.
 884  */
 885 static int usb_register_bus(struct usb_bus *bus)
 886 {
 887         int result = -E2BIG;
 888         int busnum;
 889
 890         mutex_lock(&usb_bus_list_lock);
 891         busnum = find_next_zero_bit (busmap.busmap, USB_MAXBUS, 1);
 892         if (busnum >= USB_MAXBUS) {
 893                 printk (KERN_ERR "%s: too many buses\n", usbcore_name);
 894                 goto error_find_busnum;
 895         }
 896         set_bit (busnum, busmap.busmap);
 897         bus->busnum = busnum;
 898
 899         /* Add it to the local list of buses */
 900         list_add (&bus->bus_list, &usb_bus_list);
 901         mutex_unlock(&usb_bus_list_lock);
 902
 903         usb_notify_add_bus(bus);
 904
 905         dev_info (bus->controller, "new USB bus registered, assigned bus "
 906                   "number %d\n", bus->busnum);
 907         return 0;
 908
 909 error_find_busnum:
 910         mutex_unlock(&usb_bus_list_lock);
 911         return result;
 912 }
 913
 914 /**
 915  * usb_deregister_bus - deregisters the USB host controller
 916  * @bus: pointer to the bus to deregister
 917  * Context: !in_interrupt()
 918  *
 919  * Recycles the bus number, and unlinks the controller from usbcore data
 920  * structures so that it won't be seen by scanning the bus list.
 921  */
 922 static void usb_deregister_bus (struct usb_bus *bus)
 923 {
 924         dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
 925
 926         /*
 927          * NOTE: make sure that all the devices are removed by the
 928          * controller code, as well as having it call this when cleaning
 929          * itself up
 930          */
 931         mutex_lock(&usb_bus_list_lock);
 932         list_del (&bus->bus_list);
 933         mutex_unlock(&usb_bus_list_lock);
 934
 935         usb_notify_remove_bus(bus);
 936
 937         clear_bit (bus->busnum, busmap.busmap);
 938 }
 939
 940 /**
 941  * register_root_hub - called by usb_add_hcd() to register a root hub
 942  * @hcd: host controller for this root hub
 943  *
 944  * This function registers the root hub with the USB subsystem.  It sets up
 945  * the device properly in the device tree and then calls usb_new_device()
 946  * to register the usb device.  It also assigns the root hub's USB address
 947  * (always 1).
 948  */
 949 static int register_root_hub(struct usb_hcd *hcd)
 950 {
 951         struct device *parent_dev = hcd->self.controller;
 952         struct usb_device *usb_dev = hcd->self.root_hub;
 953         const int devnum = 1;
 954         int retval;
 955
 956         usb_dev->devnum = devnum;
 957         usb_dev->bus->devnum_next = devnum + 1;
 958         memset (&usb_dev->bus->devmap.devicemap, 0,
 959                         sizeof usb_dev->bus->devmap.devicemap);
 960         set_bit (devnum, usb_dev->bus->devmap.devicemap);
 961         usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
 962
 963         mutex_lock(&usb_bus_list_lock);
 964
 965         usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
 966         retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
 967         if (retval != sizeof usb_dev->descriptor) {
 968                 mutex_unlock(&usb_bus_list_lock);
 969                 dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
 970                                 dev_name(&usb_dev->dev), retval);
 971                 return (retval < 0) ? retval : -EMSGSIZE;
 972         }
 973
 974         retval = usb_new_device (usb_dev);
 975         if (retval) {
 976                 dev_err (parent_dev, "can't register root hub for %s, %d\n",
 977                                 dev_name(&usb_dev->dev), retval);
 978         }
 979         mutex_unlock(&usb_bus_list_lock);
 980
 981         if (retval == 0) {
 982                 spin_lock_irq (&hcd_root_hub_lock);
 983                 hcd->rh_registered = 1;
 984                 spin_unlock_irq (&hcd_root_hub_lock);
 985
 986                 /* Did the HC die before the root hub was registered? */
 987                 if (hcd->state == HC_STATE_HALT)
 988                         usb_hc_died (hcd);      /* This time clean up */
 989         }
 990
 991         return retval;
 992 }
 993
 994
 995 /*-------------------------------------------------------------------------*/
 996
 997 /**
 998  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
 999  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1000  * @is_input: true iff the transaction sends data to the host
1001  * @isoc: true for isochronous transactions, false for interrupt ones
1002  * @bytecount: how many bytes in the transaction.
1003  *
1004  * Returns approximate bus time in nanoseconds for a periodic transaction.
1005  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1006  * scheduled in software, this function is only used for such scheduling.
1007  */
1008 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1009 {
1010         unsigned long   tmp;
1011
1012         switch (speed) {
1013         case USB_SPEED_LOW:     /* INTR only */
1014                 if (is_input) {
1015                         tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1016                         return (64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
1017                 } else {
1018                         tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1019                         return (64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
1020                 }
1021         case USB_SPEED_FULL:    /* ISOC or INTR */
1022                 if (isoc) {
1023                         tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1024                         return (((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp);
1025                 } else {
1026                         tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1027                         return (9107L + BW_HOST_DELAY + tmp);
1028                 }
1029         case USB_SPEED_HIGH:    /* ISOC or INTR */
1030                 // FIXME adjust for input vs output
1031                 if (isoc)
1032                         tmp = HS_NSECS_ISO (bytecount);
1033                 else
1034                         tmp = HS_NSECS (bytecount);
1035                 return tmp;
1036         default:
1037                 pr_debug ("%s: bogus device speed!\n", usbcore_name);
1038                 return -1;
1039         }
1040 }
1041 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1042
1043
1044 /*-------------------------------------------------------------------------*/
1045
1046 /*
1047  * Generic HC operations.
1048  */
1049
1050 /*-------------------------------------------------------------------------*/
1051
1052 /**
1053  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1054  * @hcd: host controller to which @urb was submitted
1055  * @urb: URB being submitted
1056  *
1057  * Host controller drivers should call this routine in their enqueue()
1058  * method.  The HCD's private spinlock must be held and interrupts must
1059  * be disabled.  The actions carried out here are required for URB
1060  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1061  *
1062  * Returns 0 for no error, otherwise a negative error code (in which case
1063  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1064  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1065  * the private spinlock and returning.
1066  */
1067 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1068 {
1069         int             rc = 0;
1070
1071         spin_lock(&hcd_urb_list_lock);
1072
1073         /* Check that the URB isn't being killed */
1074         if (unlikely(atomic_read(&urb->reject))) {
1075                 rc = -EPERM;
1076                 goto done;
1077         }
1078
1079         if (unlikely(!urb->ep->enabled)) {
1080                 rc = -ENOENT;
1081                 goto done;
1082         }
1083
1084         if (unlikely(!urb->dev->can_submit)) {
1085                 rc = -EHOSTUNREACH;
1086                 goto done;
1087         }
1088
1089         /*
1090          * Check the host controller's state and add the URB to the
1091          * endpoint's queue.
1092          */
1093         switch (hcd->state) {
1094         case HC_STATE_RUNNING:
1095         case HC_STATE_RESUMING:
1096                 urb->unlinked = 0;
1097                 list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1098                 break;
1099         default:
1100                 rc = -ESHUTDOWN;
1101                 goto done;
1102         }
1103  done:
1104         spin_unlock(&hcd_urb_list_lock);
1105         return rc;
1106 }
1107 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1108
1109 /**
1110  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1111  * @hcd: host controller to which @urb was submitted
1112  * @urb: URB being checked for unlinkability
1113  * @status: error code to store in @urb if the unlink succeeds
1114  *
1115  * Host controller drivers should call this routine in their dequeue()
1116  * method.  The HCD's private spinlock must be held and interrupts must
1117  * be disabled.  The actions carried out here are required for making
1118  * sure than an unlink is valid.
1119  *
1120  * Returns 0 for no error, otherwise a negative error code (in which case
1121  * the dequeue() method must fail).  The possible error codes are:
1122  *
1123  *      -EIDRM: @urb was not submitted or has already completed.
1124  *              The completion function may not have been called yet.
1125  *
1126  *      -EBUSY: @urb has already been unlinked.
1127  */
1128 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1129                 int status)
1130 {
1131         struct list_head        *tmp;
1132
1133         /* insist the urb is still queued */
1134         list_for_each(tmp, &urb->ep->urb_list) {
1135                 if (tmp == &urb->urb_list)
1136                         break;
1137         }
1138         if (tmp != &urb->urb_list)
1139                 return -EIDRM;
1140
1141         /* Any status except -EINPROGRESS means something already started to
1142          * unlink this URB from the hardware.  So there's no more work to do.
1143          */
1144         if (urb->unlinked)
1145                 return -EBUSY;
1146         urb->unlinked = status;
1147
1148         /* IRQ setup can easily be broken so that USB controllers
1149          * never get completion IRQs ... maybe even the ones we need to
1150          * finish unlinking the initial failed usb_set_address()
1151          * or device descriptor fetch.
1152          */
1153         if (!HCD_SAW_IRQ(hcd) && !is_root_hub(urb->dev)) {
1154                 dev_warn(hcd->self.controller, "Unlink after no-IRQ?  "
1155                         "Controller is probably using the wrong IRQ.\n");
1156                 set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
1157         }
1158
1159         return 0;
1160 }
1161 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1162
1163 /**
1164  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1165  * @hcd: host controller to which @urb was submitted
1166  * @urb: URB being unlinked
1167  *
1168  * Host controller drivers should call this routine before calling
1169  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1170  * interrupts must be disabled.  The actions carried out here are required
1171  * for URB completion.
1172  */
1173 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1174 {
1175         /* clear all state linking urb to this dev (and hcd) */
1176         spin_lock(&hcd_urb_list_lock);
1177         list_del_init(&urb->urb_list);
1178         spin_unlock(&hcd_urb_list_lock);
1179 }
1180 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1181
1182 /*
1183  * Some usb host controllers can only perform dma using a small SRAM area.
1184  * The usb core itself is however optimized for host controllers that can dma
1185  * using regular system memory - like pci devices doing bus mastering.
1186  *
1187  * To support host controllers with limited dma capabilites we provide dma
1188  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1189  * For this to work properly the host controller code must first use the
1190  * function dma_declare_coherent_memory() to point out which memory area
1191  * that should be used for dma allocations.
1192  *
1193  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1194  * dma using dma_alloc_coherent() which in turn allocates from the memory
1195  * area pointed out with dma_declare_coherent_memory().
1196  *
1197  * So, to summarize...
1198  *
1199  * - We need "local" memory, canonical example being
1200  *   a small SRAM on a discrete controller being the
1201  *   only memory that the controller can read ...
1202  *   (a) "normal" kernel memory is no good, and
1203  *   (b) there's not enough to share
1204  *
1205  * - The only *portable* hook for such stuff in the
1206  *   DMA framework is dma_declare_coherent_memory()
1207  *
1208  * - So we use that, even though the primary requirement
1209  *   is that the memory be "local" (hence addressible
1210  *   by that device), not "coherent".
1211  *
1212  */
1213
1214 static int hcd_alloc_coherent(struct usb_bus *bus,
1215                               gfp_t mem_flags, dma_addr_t *dma_handle,
1216                               void **vaddr_handle, size_t size,
1217                               enum dma_data_direction dir)
1218 {
1219         unsigned char *vaddr;
1220
1221         if (*vaddr_handle == NULL) {
1222                 WARN_ON_ONCE(1);
1223                 return -EFAULT;
1224         }
1225
1226         vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1227                                  mem_flags, dma_handle);
1228         if (!vaddr)
1229                 return -ENOMEM;
1230
1231         /*
1232          * Store the virtual address of the buffer at the end
1233          * of the allocated dma buffer. The size of the buffer
1234          * may be uneven so use unaligned functions instead
1235          * of just rounding up. It makes sense to optimize for
1236          * memory footprint over access speed since the amount
1237          * of memory available for dma may be limited.
1238          */
1239         put_unaligned((unsigned long)*vaddr_handle,
1240                       (unsigned long *)(vaddr + size));
1241
1242         if (dir == DMA_TO_DEVICE)
1243                 memcpy(vaddr, *vaddr_handle, size);
1244
1245         *vaddr_handle = vaddr;
1246         return 0;
1247 }
1248
1249 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1250                               void **vaddr_handle, size_t size,
1251                               enum dma_data_direction dir)
1252 {
1253         unsigned char *vaddr = *vaddr_handle;
1254
1255         vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1256
1257         if (dir == DMA_FROM_DEVICE)
1258                 memcpy(vaddr, *vaddr_handle, size);
1259
1260         hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1261
1262         *vaddr_handle = vaddr;
1263         *dma_handle = 0;
1264 }
1265
1266 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1267 {
1268         if (hcd->driver->unmap_urb_for_dma)
1269                 hcd->driver->unmap_urb_for_dma(hcd, urb);
1270         else
1271                 usb_hcd_unmap_urb_for_dma(hcd, urb);
1272 }
1273
1274 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1275 {
1276         enum dma_data_direction dir;
1277
1278         if (urb->transfer_flags & URB_SETUP_MAP_SINGLE)
1279                 dma_unmap_single(hcd->self.controller,
1280                                 urb->setup_dma,
1281                                 sizeof(struct usb_ctrlrequest),
1282                                 DMA_TO_DEVICE);
1283         else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1284                 hcd_free_coherent(urb->dev->bus,
1285                                 &urb->setup_dma,
1286                                 (void **) &urb->setup_packet,
1287                                 sizeof(struct usb_ctrlrequest),
1288                                 DMA_TO_DEVICE);
1289
1290         dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1291         if (urb->transfer_flags & URB_DMA_MAP_SG)
1292                 dma_unmap_sg(hcd->self.controller,
1293                                 urb->sg,
1294                                 urb->num_sgs,
1295                                 dir);
1296         else if (urb->transfer_flags & URB_DMA_MAP_PAGE)
1297                 dma_unmap_page(hcd->self.controller,
1298                                 urb->transfer_dma,
1299                                 urb->transfer_buffer_length,
1300                                 dir);
1301         else if (urb->transfer_flags & URB_DMA_MAP_SINGLE)
1302                 dma_unmap_single(hcd->self.controller,
1303                                 urb->transfer_dma,
1304                                 urb->transfer_buffer_length,
1305                                 dir);
1306         else if (urb->transfer_flags & URB_MAP_LOCAL)
1307                 hcd_free_coherent(urb->dev->bus,
1308                                 &urb->transfer_dma,
1309                                 &urb->transfer_buffer,
1310                                 urb->transfer_buffer_length,
1311                                 dir);
1312
1313         /* Make it safe to call this routine more than once */
1314         urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL |
1315                         URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1316                         URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1317 }
1318 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1319
1320 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1321                            gfp_t mem_flags)
1322 {
1323         if (hcd->driver->map_urb_for_dma)
1324                 return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1325         else
1326                 return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1327 }
1328
1329 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1330                             gfp_t mem_flags)
1331 {
1332         enum dma_data_direction dir;
1333         int ret = 0;
1334
1335         /* Map the URB's buffers for DMA access.
1336          * Lower level HCD code should use *_dma exclusively,
1337          * unless it uses pio or talks to another transport,
1338          * or uses the provided scatter gather list for bulk.
1339          */
1340
1341         if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1342                 if (hcd->self.uses_dma) {
1343                         urb->setup_dma = dma_map_single(
1344                                         hcd->self.controller,
1345                                         urb->setup_packet,
1346                                         sizeof(struct usb_ctrlrequest),
1347                                         DMA_TO_DEVICE);
1348                         if (dma_mapping_error(hcd->self.controller,
1349                                                 urb->setup_dma))
1350                                 return -EAGAIN;
1351                         urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1352                 } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1353                         ret = hcd_alloc_coherent(
1354                                         urb->dev->bus, mem_flags,
1355                                         &urb->setup_dma,
1356                                         (void **)&urb->setup_packet,
1357                                         sizeof(struct usb_ctrlrequest),
1358                                         DMA_TO_DEVICE);
1359                         if (ret)
1360                                 return ret;
1361                         urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1362                 }
1363         }
1364
1365         dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1366         if (urb->transfer_buffer_length != 0
1367             && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1368                 if (hcd->self.uses_dma) {
1369                         if (urb->num_sgs) {
1370                                 int n = dma_map_sg(
1371                                                 hcd->self.controller,
1372                                                 urb->sg,
1373                                                 urb->num_sgs,
1374                                                 dir);
1375                                 if (n <= 0)
1376                                         ret = -EAGAIN;
1377                                 else
1378                                         urb->transfer_flags |= URB_DMA_MAP_SG;
1379                                 if (n != urb->num_sgs) {
1380                                         urb->num_sgs = n;
1381                                         urb->transfer_flags |=
1382                                                         URB_DMA_SG_COMBINED;
1383                                 }
1384                         } else if (urb->sg) {
1385                                 struct scatterlist *sg = urb->sg;
1386                                 urb->transfer_dma = dma_map_page(
1387                                                 hcd->self.controller,
1388                                                 sg_page(sg),
1389                                                 sg->offset,
1390                                                 urb->transfer_buffer_length,
1391                                                 dir);
1392                                 if (dma_mapping_error(hcd->self.controller,
1393                                                 urb->transfer_dma))
1394                                         ret = -EAGAIN;
1395                                 else
1396                                         urb->transfer_flags |= URB_DMA_MAP_PAGE;
1397                         } else {
1398                                 urb->transfer_dma = dma_map_single(
1399                                                 hcd->self.controller,
1400                                                 urb->transfer_buffer,
1401                                                 urb->transfer_buffer_length,
1402                                                 dir);
1403                                 if (dma_mapping_error(hcd->self.controller,
1404                                                 urb->transfer_dma))
1405                                         ret = -EAGAIN;
1406                                 else
1407                                         urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1408                         }
1409                 } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1410                         ret = hcd_alloc_coherent(
1411                                         urb->dev->bus, mem_flags,
1412                                         &urb->transfer_dma,
1413                                         &urb->transfer_buffer,
1414                                         urb->transfer_buffer_length,
1415                                         dir);
1416                         if (ret == 0)
1417                                 urb->transfer_flags |= URB_MAP_LOCAL;
1418                 }
1419                 if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1420                                 URB_SETUP_MAP_LOCAL)))
1421                         usb_hcd_unmap_urb_for_dma(hcd, urb);
1422         }
1423         return ret;
1424 }
1425 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1426
1427 /*-------------------------------------------------------------------------*/
1428
1429 /* may be called in any context with a valid urb->dev usecount
1430  * caller surrenders "ownership" of urb
1431  * expects usb_submit_urb() to have sanity checked and conditioned all
1432  * inputs in the urb
1433  */
1434 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1435 {
1436         int                     status;
1437         struct usb_hcd          *hcd = bus_to_hcd(urb->dev->bus);
1438
1439         /* increment urb's reference count as part of giving it to the HCD
1440          * (which will control it).  HCD guarantees that it either returns
1441          * an error or calls giveback(), but not both.
1442          */
1443         usb_get_urb(urb);
1444         atomic_inc(&urb->use_count);
1445         atomic_inc(&urb->dev->urbnum);
1446         usbmon_urb_submit(&hcd->self, urb);
1447
1448         /* NOTE requirements on root-hub callers (usbfs and the hub
1449          * driver, for now):  URBs' urb->transfer_buffer must be
1450          * valid and usb_buffer_{sync,unmap}() not be needed, since
1451          * they could clobber root hub response data.  Also, control
1452          * URBs must be submitted in process context with interrupts
1453          * enabled.
1454          */
1455
1456         if (is_root_hub(urb->dev)) {
1457                 status = rh_urb_enqueue(hcd, urb);
1458         } else {
1459                 status = map_urb_for_dma(hcd, urb, mem_flags);
1460                 if (likely(status == 0)) {
1461                         status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1462                         if (unlikely(status))
1463                                 unmap_urb_for_dma(hcd, urb);
1464                 }
1465         }
1466
1467         if (unlikely(status)) {
1468                 usbmon_urb_submit_error(&hcd->self, urb, status);
1469                 urb->hcpriv = NULL;
1470                 INIT_LIST_HEAD(&urb->urb_list);
1471                 atomic_dec(&urb->use_count);
1472                 atomic_dec(&urb->dev->urbnum);
1473                 if (atomic_read(&urb->reject))
1474                         wake_up(&usb_kill_urb_queue);
1475                 usb_put_urb(urb);
1476         }
1477         return status;
1478 }
1479
1480 /*-------------------------------------------------------------------------*/
1481
1482 /* this makes the hcd giveback() the urb more quickly, by kicking it
1483  * off hardware queues (which may take a while) and returning it as
1484  * soon as practical.  we've already set up the urb's return status,
1485  * but we can't know if the callback completed already.
1486  */
1487 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1488 {
1489         int             value;
1490
1491         if (is_root_hub(urb->dev))
1492                 value = usb_rh_urb_dequeue(hcd, urb, status);
1493         else {
1494
1495                 /* The only reason an HCD might fail this call is if
1496                  * it has not yet fully queued the urb to begin with.
1497                  * Such failures should be harmless. */
1498                 value = hcd->driver->urb_dequeue(hcd, urb, status);
1499         }
1500         return value;
1501 }
1502
1503 /*
1504  * called in any context
1505  *
1506  * caller guarantees urb won't be recycled till both unlink()
1507  * and the urb's completion function return
1508  */
1509 int usb_hcd_unlink_urb (struct urb *urb, int status)
1510 {
1511         struct usb_hcd          *hcd;
1512         int                     retval = -EIDRM;
1513         unsigned long           flags;
1514
1515         /* Prevent the device and bus from going away while
1516          * the unlink is carried out.  If they are already gone
1517          * then urb->use_count must be 0, since disconnected
1518          * devices can't have any active URBs.
1519          */
1520         spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1521         if (atomic_read(&urb->use_count) > 0) {
1522                 retval = 0;
1523                 usb_get_dev(urb->dev);
1524         }
1525         spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1526         if (retval == 0) {
1527                 hcd = bus_to_hcd(urb->dev->bus);
1528                 retval = unlink1(hcd, urb, status);
1529                 usb_put_dev(urb->dev);
1530         }
1531
1532         if (retval == 0)
1533                 retval = -EINPROGRESS;
1534         else if (retval != -EIDRM && retval != -EBUSY)
1535                 dev_dbg(&urb->dev->dev, "hcd_unlink_urb %p fail %d\n",
1536                                 urb, retval);
1537         return retval;
1538 }
1539
1540 /*-------------------------------------------------------------------------*/
1541
1542 /**
1543  * usb_hcd_giveback_urb - return URB from HCD to device driver
1544  * @hcd: host controller returning the URB
1545  * @urb: urb being returned to the USB device driver.
1546  * @status: completion status code for the URB.
1547  * Context: in_interrupt()
1548  *
1549  * This hands the URB from HCD to its USB device driver, using its
1550  * completion function.  The HCD has freed all per-urb resources
1551  * (and is done using urb->hcpriv).  It also released all HCD locks;
1552  * the device driver won't cause problems if it frees, modifies,
1553  * or resubmits this URB.
1554  *
1555  * If @urb was unlinked, the value of @status will be overridden by
1556  * @urb->unlinked.  Erroneous short transfers are detected in case
1557  * the HCD hasn't checked for them.
1558  */
1559 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1560 {
1561         urb->hcpriv = NULL;
1562         if (unlikely(urb->unlinked))
1563                 status = urb->unlinked;
1564         else if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1565                         urb->actual_length < urb->transfer_buffer_length &&
1566                         !status))
1567                 status = -EREMOTEIO;
1568
1569         unmap_urb_for_dma(hcd, urb);
1570         usbmon_urb_complete(&hcd->self, urb, status);
1571         usb_unanchor_urb(urb);
1572
1573         /* pass ownership to the completion handler */
1574         urb->status = status;
1575         urb->complete (urb);
1576         atomic_dec (&urb->use_count);
1577         if (unlikely(atomic_read(&urb->reject)))
1578                 wake_up (&usb_kill_urb_queue);
1579         usb_put_urb (urb);
1580 }
1581 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1582
1583 /*-------------------------------------------------------------------------*/
1584
1585 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1586  * queue to drain completely.  The caller must first insure that no more
1587  * URBs can be submitted for this endpoint.
1588  */
1589 void usb_hcd_flush_endpoint(struct usb_device *udev,
1590                 struct usb_host_endpoint *ep)
1591 {
1592         struct usb_hcd          *hcd;
1593         struct urb              *urb;
1594
1595         if (!ep)
1596                 return;
1597         might_sleep();
1598         hcd = bus_to_hcd(udev->bus);
1599
1600         /* No more submits can occur */
1601         spin_lock_irq(&hcd_urb_list_lock);
1602 rescan:
1603         list_for_each_entry (urb, &ep->urb_list, urb_list) {
1604                 int     is_in;
1605
1606                 if (urb->unlinked)
1607                         continue;
1608                 usb_get_urb (urb);
1609                 is_in = usb_urb_dir_in(urb);
1610                 spin_unlock(&hcd_urb_list_lock);
1611
1612                 /* kick hcd */
1613                 unlink1(hcd, urb, -ESHUTDOWN);
1614                 dev_dbg (hcd->self.controller,
1615                         "shutdown urb %p ep%d%s%s\n",
1616                         urb, usb_endpoint_num(&ep->desc),
1617                         is_in ? "in" : "out",
1618                         ({      char *s;
1619
1620                                  switch (usb_endpoint_type(&ep->desc)) {
1621                                  case USB_ENDPOINT_XFER_CONTROL:
1622                                         s = ""; break;
1623                                  case USB_ENDPOINT_XFER_BULK:
1624                                         s = "-bulk"; break;
1625                                  case USB_ENDPOINT_XFER_INT:
1626                                         s = "-intr"; break;
1627                                  default:
1628                                         s = "-iso"; break;
1629                                 };
1630                                 s;
1631                         }));
1632                 usb_put_urb (urb);
1633
1634                 /* list contents may have changed */
1635                 spin_lock(&hcd_urb_list_lock);
1636                 goto rescan;
1637         }
1638         spin_unlock_irq(&hcd_urb_list_lock);
1639
1640         /* Wait until the endpoint queue is completely empty */
1641         while (!list_empty (&ep->urb_list)) {
1642                 spin_lock_irq(&hcd_urb_list_lock);
1643
1644                 /* The list may have changed while we acquired the spinlock */
1645                 urb = NULL;
1646                 if (!list_empty (&ep->urb_list)) {
1647                         urb = list_entry (ep->urb_list.prev, struct urb,
1648                                         urb_list);
1649                         usb_get_urb (urb);
1650                 }
1651                 spin_unlock_irq(&hcd_urb_list_lock);
1652
1653                 if (urb) {
1654                         usb_kill_urb (urb);
1655                         usb_put_urb (urb);
1656                 }
1657         }
1658 }
1659
1660 /**
1661  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1662  *                              the bus bandwidth
1663  * @udev: target &usb_device
1664  * @new_config: new configuration to install
1665  * @cur_alt: the current alternate interface setting
1666  * @new_alt: alternate interface setting that is being installed
1667  *
1668  * To change configurations, pass in the new configuration in new_config,
1669  * and pass NULL for cur_alt and new_alt.
1670  *
1671  * To reset a device's configuration (put the device in the ADDRESSED state),
1672  * pass in NULL for new_config, cur_alt, and new_alt.
1673  *
1674  * To change alternate interface settings, pass in NULL for new_config,
1675  * pass in the current alternate interface setting in cur_alt,
1676  * and pass in the new alternate interface setting in new_alt.
1677  *
1678  * Returns an error if the requested bandwidth change exceeds the
1679  * bus bandwidth or host controller internal resources.
1680  */
1681 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1682                 struct usb_host_config *new_config,
1683                 struct usb_host_interface *cur_alt,
1684                 struct usb_host_interface *new_alt)
1685 {
1686         int num_intfs, i, j;
1687         struct usb_host_interface *alt = NULL;
1688         int ret = 0;
1689         struct usb_hcd *hcd;
1690         struct usb_host_endpoint *ep;
1691
1692         hcd = bus_to_hcd(udev->bus);
1693         if (!hcd->driver->check_bandwidth)
1694                 return 0;
1695
1696         /* Configuration is being removed - set configuration 0 */
1697         if (!new_config && !cur_alt) {
1698                 for (i = 1; i < 16; ++i) {
1699                         ep = udev->ep_out[i];
1700                         if (ep)
1701                                 hcd->driver->drop_endpoint(hcd, udev, ep);
1702                         ep = udev->ep_in[i];
1703                         if (ep)
1704                                 hcd->driver->drop_endpoint(hcd, udev, ep);
1705                 }
1706                 hcd->driver->check_bandwidth(hcd, udev);
1707                 return 0;
1708         }
1709         /* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1710          * each interface's alt setting 0 and ask the HCD to check the bandwidth
1711          * of the bus.  There will always be bandwidth for endpoint 0, so it's
1712          * ok to exclude it.
1713          */
1714         if (new_config) {
1715                 num_intfs = new_config->desc.bNumInterfaces;
1716                 /* Remove endpoints (except endpoint 0, which is always on the
1717                  * schedule) from the old config from the schedule
1718                  */
1719                 for (i = 1; i < 16; ++i) {
1720                         ep = udev->ep_out[i];
1721                         if (ep) {
1722                                 ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1723                                 if (ret < 0)
1724                                         goto reset;
1725                         }
1726                         ep = udev->ep_in[i];
1727                         if (ep) {
1728                                 ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1729                                 if (ret < 0)
1730                                         goto reset;
1731                         }
1732                 }
1733                 for (i = 0; i < num_intfs; ++i) {
1734                         struct usb_host_interface *first_alt;
1735                         int iface_num;
1736
1737                         first_alt = &new_config->intf_cache[i]->altsetting[0];
1738                         iface_num = first_alt->desc.bInterfaceNumber;
1739                         /* Set up endpoints for alternate interface setting 0 */
1740                         alt = usb_find_alt_setting(new_config, iface_num, 0);
1741                         if (!alt)
1742                                 /* No alt setting 0? Pick the first setting. */
1743                                 alt = first_alt;
1744
1745                         for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1746                                 ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1747                                 if (ret < 0)
1748                                         goto reset;
1749                         }
1750                 }
1751         }
1752         if (cur_alt && new_alt) {
1753                 struct usb_interface *iface = usb_ifnum_to_if(udev,
1754                                 cur_alt->desc.bInterfaceNumber);
1755
1756                 if (iface->resetting_device) {
1757                         /*
1758                          * The USB core just reset the device, so the xHCI host
1759                          * and the device will think alt setting 0 is installed.
1760                          * However, the USB core will pass in the alternate
1761                          * setting installed before the reset as cur_alt.  Dig
1762                          * out the alternate setting 0 structure, or the first
1763                          * alternate setting if a broken device doesn't have alt
1764                          * setting 0.
1765                          */
1766                         cur_alt = usb_altnum_to_altsetting(iface, 0);
1767                         if (!cur_alt)
1768                                 cur_alt = &iface->altsetting[0];
1769                 }
1770
1771                 /* Drop all the endpoints in the current alt setting */
1772                 for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1773                         ret = hcd->driver->drop_endpoint(hcd, udev,
1774                                         &cur_alt->endpoint[i]);
1775                         if (ret < 0)
1776                                 goto reset;
1777                 }
1778                 /* Add all the endpoints in the new alt setting */
1779                 for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1780                         ret = hcd->driver->add_endpoint(hcd, udev,
1781                                         &new_alt->endpoint[i]);
1782                         if (ret < 0)
1783                                 goto reset;
1784                 }
1785         }
1786         ret = hcd->driver->check_bandwidth(hcd, udev);
1787 reset:
1788         if (ret < 0)
1789                 hcd->driver->reset_bandwidth(hcd, udev);
1790         return ret;
1791 }
1792
1793 /* Disables the endpoint: synchronizes with the hcd to make sure all
1794  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1795  * have been called previously.  Use for set_configuration, set_interface,
1796  * driver removal, physical disconnect.
1797  *
1798  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1799  * type, maxpacket size, toggle, halt status, and scheduling.
1800  */
1801 void usb_hcd_disable_endpoint(struct usb_device *udev,
1802                 struct usb_host_endpoint *ep)
1803 {
1804         struct usb_hcd          *hcd;
1805
1806         might_sleep();
1807         hcd = bus_to_hcd(udev->bus);
1808         if (hcd->driver->endpoint_disable)
1809                 hcd->driver->endpoint_disable(hcd, ep);
1810 }
1811
1812 /**
1813  * usb_hcd_reset_endpoint - reset host endpoint state
1814  * @udev: USB device.
1815  * @ep:   the endpoint to reset.
1816  *
1817  * Resets any host endpoint state such as the toggle bit, sequence
1818  * number and current window.
1819  */
1820 void usb_hcd_reset_endpoint(struct usb_device *udev,
1821                             struct usb_host_endpoint *ep)
1822 {
1823         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1824
1825         if (hcd->driver->endpoint_reset)
1826                 hcd->driver->endpoint_reset(hcd, ep);
1827         else {
1828                 int epnum = usb_endpoint_num(&ep->desc);
1829                 int is_out = usb_endpoint_dir_out(&ep->desc);
1830                 int is_control = usb_endpoint_xfer_control(&ep->desc);
1831
1832                 usb_settoggle(udev, epnum, is_out, 0);
1833                 if (is_control)
1834                         usb_settoggle(udev, epnum, !is_out, 0);
1835         }
1836 }
1837
1838 /**
1839  * usb_alloc_streams - allocate bulk endpoint stream IDs.
1840  * @interface:          alternate setting that includes all endpoints.
1841  * @eps:                array of endpoints that need streams.
1842  * @num_eps:            number of endpoints in the array.
1843  * @num_streams:        number of streams to allocate.
1844  * @mem_flags:          flags hcd should use to allocate memory.
1845  *
1846  * Sets up a group of bulk endpoints to have num_streams stream IDs available.
1847  * Drivers may queue multiple transfers to different stream IDs, which may
1848  * complete in a different order than they were queued.
1849  */
1850 int usb_alloc_streams(struct usb_interface *interface,
1851                 struct usb_host_endpoint **eps, unsigned int num_eps,
1852                 unsigned int num_streams, gfp_t mem_flags)
1853 {
1854         struct usb_hcd *hcd;
1855         struct usb_device *dev;
1856         int i;
1857
1858         dev = interface_to_usbdev(interface);
1859         hcd = bus_to_hcd(dev->bus);
1860         if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
1861                 return -EINVAL;
1862         if (dev->speed != USB_SPEED_SUPER)
1863                 return -EINVAL;
1864
1865         /* Streams only apply to bulk endpoints. */
1866         for (i = 0; i < num_eps; i++)
1867                 if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
1868                         return -EINVAL;
1869
1870         return hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
1871                         num_streams, mem_flags);
1872 }
1873 EXPORT_SYMBOL_GPL(usb_alloc_streams);
1874
1875 /**
1876  * usb_free_streams - free bulk endpoint stream IDs.
1877  * @interface:  alternate setting that includes all endpoints.
1878  * @eps:        array of endpoints to remove streams from.
1879  * @num_eps:    number of endpoints in the array.
1880  * @mem_flags:  flags hcd should use to allocate memory.
1881  *
1882  * Reverts a group of bulk endpoints back to not using stream IDs.
1883  * Can fail if we are given bad arguments, or HCD is broken.
1884  */
1885 void usb_free_streams(struct usb_interface *interface,
1886                 struct usb_host_endpoint **eps, unsigned int num_eps,
1887                 gfp_t mem_flags)
1888 {
1889         struct usb_hcd *hcd;
1890         struct usb_device *dev;
1891         int i;
1892
1893         dev = interface_to_usbdev(interface);
1894         hcd = bus_to_hcd(dev->bus);
1895         if (dev->speed != USB_SPEED_SUPER)
1896                 return;
1897
1898         /* Streams only apply to bulk endpoints. */
1899         for (i = 0; i < num_eps; i++)
1900                 if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
1901                         return;
1902
1903         hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
1904 }
1905 EXPORT_SYMBOL_GPL(usb_free_streams);
1906
1907 /* Protect against drivers that try to unlink URBs after the device
1908  * is gone, by waiting until all unlinks for @udev are finished.
1909  * Since we don't currently track URBs by device, simply wait until
1910  * nothing is running in the locked region of usb_hcd_unlink_urb().
1911  */
1912 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
1913 {
1914         spin_lock_irq(&hcd_urb_unlink_lock);
1915         spin_unlock_irq(&hcd_urb_unlink_lock);
1916 }
1917
1918 /*-------------------------------------------------------------------------*/
1919
1920 /* called in any context */
1921 int usb_hcd_get_frame_number (struct usb_device *udev)
1922 {
1923         struct usb_hcd  *hcd = bus_to_hcd(udev->bus);
1924
1925         if (!HC_IS_RUNNING (hcd->state))
1926                 return -ESHUTDOWN;
1927         return hcd->driver->get_frame_number (hcd);
1928 }
1929
1930 /*-------------------------------------------------------------------------*/
1931
1932 #ifdef  CONFIG_PM
1933
1934 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
1935 {
1936         struct usb_hcd  *hcd = container_of(rhdev->bus, struct usb_hcd, self);
1937         int             status;
1938         int             old_state = hcd->state;
1939
1940         dev_dbg(&rhdev->dev, "bus %s%s\n",
1941                         (msg.event & PM_EVENT_AUTO ? "auto-" : ""), "suspend");
1942         if (!hcd->driver->bus_suspend) {
1943                 status = -ENOENT;
1944         } else {
1945                 hcd->state = HC_STATE_QUIESCING;
1946                 status = hcd->driver->bus_suspend(hcd);
1947         }
1948         if (status == 0) {
1949                 usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
1950                 hcd->state = HC_STATE_SUSPENDED;
1951         } else {
1952                 hcd->state = old_state;
1953                 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
1954                                 "suspend", status);
1955         }
1956         return status;
1957 }
1958
1959 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
1960 {
1961         struct usb_hcd  *hcd = container_of(rhdev->bus, struct usb_hcd, self);
1962         int             status;
1963         int             old_state = hcd->state;
1964
1965         dev_dbg(&rhdev->dev, "usb %s%s\n",
1966                         (msg.event & PM_EVENT_AUTO ? "auto-" : ""), "resume");
1967         clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
1968         if (!hcd->driver->bus_resume)
1969                 return -ENOENT;
1970         if (hcd->state == HC_STATE_RUNNING)
1971                 return 0;
1972
1973         hcd->state = HC_STATE_RESUMING;
1974         status = hcd->driver->bus_resume(hcd);
1975         if (status == 0) {
1976                 /* TRSMRCY = 10 msec */
1977                 msleep(10);
1978                 usb_set_device_state(rhdev, rhdev->actconfig
1979                                 ? USB_STATE_CONFIGURED
1980                                 : USB_STATE_ADDRESS);
1981                 hcd->state = HC_STATE_RUNNING;
1982         } else {
1983                 hcd->state = old_state;
1984                 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
1985                                 "resume", status);
1986                 if (status != -ESHUTDOWN)
1987                         usb_hc_died(hcd);
1988         }
1989         return status;
1990 }
1991
1992 #endif  /* CONFIG_PM */
1993
1994 #ifdef  CONFIG_USB_SUSPEND
1995
1996 /* Workqueue routine for root-hub remote wakeup */
1997 static void hcd_resume_work(struct work_struct *work)
1998 {
1999         struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2000         struct usb_device *udev = hcd->self.root_hub;
2001
2002         usb_lock_device(udev);
2003         usb_remote_wakeup(udev);
2004         usb_unlock_device(udev);
2005 }
2006
2007 /**
2008  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2009  * @hcd: host controller for this root hub
2010  *
2011  * The USB host controller calls this function when its root hub is
2012  * suspended (with the remote wakeup feature enabled) and a remote
2013  * wakeup request is received.  The routine submits a workqueue request
2014  * to resume the root hub (that is, manage its downstream ports again).
2015  */
2016 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2017 {
2018         unsigned long flags;
2019
2020         spin_lock_irqsave (&hcd_root_hub_lock, flags);
2021         if (hcd->rh_registered) {
2022                 set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2023                 queue_work(pm_wq, &hcd->wakeup_work);
2024         }
2025         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2026 }
2027 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2028
2029 #endif  /* CONFIG_USB_SUSPEND */
2030
2031 /*-------------------------------------------------------------------------*/
2032
2033 #ifdef  CONFIG_USB_OTG
2034
2035 /**
2036  * usb_bus_start_enum - start immediate enumeration (for OTG)
2037  * @bus: the bus (must use hcd framework)
2038  * @port_num: 1-based number of port; usually bus->otg_port
2039  * Context: in_interrupt()
2040  *
2041  * Starts enumeration, with an immediate reset followed later by
2042  * khubd identifying and possibly configuring the device.
2043  * This is needed by OTG controller drivers, where it helps meet
2044  * HNP protocol timing requirements for starting a port reset.
2045  */
2046 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2047 {
2048         struct usb_hcd          *hcd;
2049         int                     status = -EOPNOTSUPP;
2050
2051         /* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2052          * boards with root hubs hooked up to internal devices (instead of
2053          * just the OTG port) may need more attention to resetting...
2054          */
2055         hcd = container_of (bus, struct usb_hcd, self);
2056         if (port_num && hcd->driver->start_port_reset)
2057                 status = hcd->driver->start_port_reset(hcd, port_num);
2058
2059         /* run khubd shortly after (first) root port reset finishes;
2060          * it may issue others, until at least 50 msecs have passed.
2061          */
2062         if (status == 0)
2063                 mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2064         return status;
2065 }
2066 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2067
2068 #endif
2069
2070 /*-------------------------------------------------------------------------*/
2071
2072 /**
2073  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2074  * @irq: the IRQ being raised
2075  * @__hcd: pointer to the HCD whose IRQ is being signaled
2076  *
2077  * If the controller isn't HALTed, calls the driver's irq handler.
2078  * Checks whether the controller is now dead.
2079  */
2080 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2081 {
2082         struct usb_hcd          *hcd = __hcd;
2083         unsigned long           flags;
2084         irqreturn_t             rc;
2085
2086         /* IRQF_DISABLED doesn't work correctly with shared IRQs
2087          * when the first handler doesn't use it.  So let's just
2088          * assume it's never used.
2089          */
2090         local_irq_save(flags);
2091
2092         if (unlikely(hcd->state == HC_STATE_HALT || !HCD_HW_ACCESSIBLE(hcd))) {
2093                 rc = IRQ_NONE;
2094         } else if (hcd->driver->irq(hcd) == IRQ_NONE) {
2095                 rc = IRQ_NONE;
2096         } else {
2097                 set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
2098
2099                 if (unlikely(hcd->state == HC_STATE_HALT))
2100                         usb_hc_died(hcd);
2101                 rc = IRQ_HANDLED;
2102         }
2103
2104         local_irq_restore(flags);
2105         return rc;
2106 }
2107 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2108
2109 /*-------------------------------------------------------------------------*/
2110
2111 /**
2112  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2113  * @hcd: pointer to the HCD representing the controller
2114  *
2115  * This is called by bus glue to report a USB host controller that died
2116  * while operations may still have been pending.  It's called automatically
2117  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2118  */
2119 void usb_hc_died (struct usb_hcd *hcd)
2120 {
2121         unsigned long flags;
2122
2123         dev_err (hcd->self.controller, "HC died; cleaning up\n");
2124
2125         spin_lock_irqsave (&hcd_root_hub_lock, flags);
2126         if (hcd->rh_registered) {
2127                 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2128
2129                 /* make khubd clean up old urbs and devices */
2130                 usb_set_device_state (hcd->self.root_hub,
2131                                 USB_STATE_NOTATTACHED);
2132                 usb_kick_khubd (hcd->self.root_hub);
2133         }
2134         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2135 }
2136 EXPORT_SYMBOL_GPL (usb_hc_died);
2137
2138 /*-------------------------------------------------------------------------*/
2139
2140 /**
2141  * usb_create_hcd - create and initialize an HCD structure
2142  * @driver: HC driver that will use this hcd
2143  * @dev: device for this HC, stored in hcd->self.controller
2144  * @bus_name: value to store in hcd->self.bus_name
2145  * Context: !in_interrupt()
2146  *
2147  * Allocate a struct usb_hcd, with extra space at the end for the
2148  * HC driver's private data.  Initialize the generic members of the
2149  * hcd structure.
2150  *
2151  * If memory is unavailable, returns NULL.
2152  */
2153 struct usb_hcd *usb_create_hcd (const struct hc_driver *driver,
2154                 struct device *dev, const char *bus_name)
2155 {
2156         struct usb_hcd *hcd;
2157
2158         hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2159         if (!hcd) {
2160                 dev_dbg (dev, "hcd alloc failed\n");
2161                 return NULL;
2162         }
2163         dev_set_drvdata(dev, hcd);
2164         kref_init(&hcd->kref);
2165
2166         usb_bus_init(&hcd->self);
2167         hcd->self.controller = dev;
2168         hcd->self.bus_name = bus_name;
2169         hcd->self.uses_dma = (dev->dma_mask != NULL);
2170
2171         init_timer(&hcd->rh_timer);
2172         hcd->rh_timer.function = rh_timer_func;
2173         hcd->rh_timer.data = (unsigned long) hcd;
2174 #ifdef CONFIG_USB_SUSPEND
2175         INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2176 #endif
2177         mutex_init(&hcd->bandwidth_mutex);
2178
2179         hcd->driver = driver;
2180         hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2181                         "USB Host Controller";
2182         return hcd;
2183 }
2184 EXPORT_SYMBOL_GPL(usb_create_hcd);
2185
2186 static void hcd_release (struct kref *kref)
2187 {
2188         struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2189
2190         kfree(hcd);
2191 }
2192
2193 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2194 {
2195         if (hcd)
2196                 kref_get (&hcd->kref);
2197         return hcd;
2198 }
2199 EXPORT_SYMBOL_GPL(usb_get_hcd);
2200
2201 void usb_put_hcd (struct usb_hcd *hcd)
2202 {
2203         if (hcd)
2204                 kref_put (&hcd->kref, hcd_release);
2205 }
2206 EXPORT_SYMBOL_GPL(usb_put_hcd);
2207
2208 /**
2209  * usb_add_hcd - finish generic HCD structure initialization and register
2210  * @hcd: the usb_hcd structure to initialize
2211  * @irqnum: Interrupt line to allocate
2212  * @irqflags: Interrupt type flags
2213  *
2214  * Finish the remaining parts of generic HCD initialization: allocate the
2215  * buffers of consistent memory, register the bus, request the IRQ line,
2216  * and call the driver's reset() and start() routines.
2217  */
2218 int usb_add_hcd(struct usb_hcd *hcd,
2219                 unsigned int irqnum, unsigned long irqflags)
2220 {
2221         int retval;
2222         struct usb_device *rhdev;
2223
2224         dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2225
2226         hcd->authorized_default = hcd->wireless? 0 : 1;
2227         set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2228
2229         /* HC is in reset state, but accessible.  Now do the one-time init,
2230          * bottom up so that hcds can customize the root hubs before khubd
2231          * starts talking to them.  (Note, bus id is assigned early too.)
2232          */
2233         if ((retval = hcd_buffer_create(hcd)) != 0) {
2234                 dev_dbg(hcd->self.controller, "pool alloc failed\n");
2235                 return retval;
2236         }
2237
2238         if ((retval = usb_register_bus(&hcd->self)) < 0)
2239                 goto err_register_bus;
2240
2241         if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
2242                 dev_err(hcd->self.controller, "unable to allocate root hub\n");
2243                 retval = -ENOMEM;
2244                 goto err_allocate_root_hub;
2245         }
2246         hcd->self.root_hub = rhdev;
2247
2248         switch (hcd->driver->flags & HCD_MASK) {
2249         case HCD_USB11:
2250                 rhdev->speed = USB_SPEED_FULL;
2251                 break;
2252         case HCD_USB2:
2253                 rhdev->speed = USB_SPEED_HIGH;
2254                 break;
2255         case HCD_USB3:
2256                 rhdev->speed = USB_SPEED_SUPER;
2257                 break;
2258         default:
2259                 goto err_set_rh_speed;
2260         }
2261
2262         /* wakeup flag init defaults to "everything works" for root hubs,
2263          * but drivers can override it in reset() if needed, along with
2264          * recording the overall controller's system wakeup capability.
2265          */
2266         device_init_wakeup(&rhdev->dev, 1);
2267
2268         /* "reset" is misnamed; its role is now one-time init. the controller
2269          * should already have been reset (and boot firmware kicked off etc).
2270          */
2271         if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
2272                 dev_err(hcd->self.controller, "can't setup\n");
2273                 goto err_hcd_driver_setup;
2274         }
2275         hcd->rh_pollable = 1;
2276
2277         /* NOTE: root hub and controller capabilities may not be the same */
2278         if (device_can_wakeup(hcd->self.controller)
2279                         && device_can_wakeup(&hcd->self.root_hub->dev))
2280                 dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2281
2282         /* enable irqs just before we start the controller */
2283         if (hcd->driver->irq) {
2284
2285                 /* IRQF_DISABLED doesn't work as advertised when used together
2286                  * with IRQF_SHARED. As usb_hcd_irq() will always disable
2287                  * interrupts we can remove it here.
2288                  */
2289                 if (irqflags & IRQF_SHARED)
2290                         irqflags &= ~IRQF_DISABLED;
2291
2292                 snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2293                                 hcd->driver->description, hcd->self.busnum);
2294                 if ((retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2295                                 hcd->irq_descr, hcd)) != 0) {
2296                         dev_err(hcd->self.controller,
2297                                         "request interrupt %d failed\n", irqnum);
2298                         goto err_request_irq;
2299                 }
2300                 hcd->irq = irqnum;
2301                 dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2302                                 (hcd->driver->flags & HCD_MEMORY) ?
2303                                         "io mem" : "io base",
2304                                         (unsigned long long)hcd->rsrc_start);
2305         } else {
2306                 hcd->irq = -1;
2307                 if (hcd->rsrc_start)
2308                         dev_info(hcd->self.controller, "%s 0x%08llx\n",
2309                                         (hcd->driver->flags & HCD_MEMORY) ?
2310                                         "io mem" : "io base",
2311                                         (unsigned long long)hcd->rsrc_start);
2312         }
2313
2314         if ((retval = hcd->driver->start(hcd)) < 0) {
2315                 dev_err(hcd->self.controller, "startup error %d\n", retval);
2316                 goto err_hcd_driver_start;
2317         }
2318
2319         /* starting here, usbcore will pay attention to this root hub */
2320         rhdev->bus_mA = min(500u, hcd->power_budget);
2321         if ((retval = register_root_hub(hcd)) != 0)
2322                 goto err_register_root_hub;
2323
2324         retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2325         if (retval < 0) {
2326                 printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2327                        retval);
2328                 goto error_create_attr_group;
2329         }
2330         if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2331                 usb_hcd_poll_rh_status(hcd);
2332         return retval;
2333
2334 error_create_attr_group:
2335         if (HC_IS_RUNNING(hcd->state))
2336                 hcd->state = HC_STATE_QUIESCING;
2337         spin_lock_irq(&hcd_root_hub_lock);
2338         hcd->rh_registered = 0;
2339         spin_unlock_irq(&hcd_root_hub_lock);
2340
2341 #ifdef CONFIG_USB_SUSPEND
2342         cancel_work_sync(&hcd->wakeup_work);
2343 #endif
2344         mutex_lock(&usb_bus_list_lock);
2345         usb_disconnect(&rhdev);         /* Sets rhdev to NULL */
2346         mutex_unlock(&usb_bus_list_lock);
2347 err_register_root_hub:
2348         hcd->rh_pollable = 0;
2349         clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2350         del_timer_sync(&hcd->rh_timer);
2351         hcd->driver->stop(hcd);
2352         hcd->state = HC_STATE_HALT;
2353         clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2354         del_timer_sync(&hcd->rh_timer);
2355 err_hcd_driver_start:
2356         if (hcd->irq >= 0)
2357                 free_irq(irqnum, hcd);
2358 err_request_irq:
2359 err_hcd_driver_setup:
2360 err_set_rh_speed:
2361         usb_put_dev(hcd->self.root_hub);
2362 err_allocate_root_hub:
2363         usb_deregister_bus(&hcd->self);
2364 err_register_bus:
2365         hcd_buffer_destroy(hcd);
2366         return retval;
2367 }
2368 EXPORT_SYMBOL_GPL(usb_add_hcd);
2369
2370 /**
2371  * usb_remove_hcd - shutdown processing for generic HCDs
2372  * @hcd: the usb_hcd structure to remove
2373  * Context: !in_interrupt()
2374  *
2375  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2376  * invoking the HCD's stop() method.
2377  */
2378 void usb_remove_hcd(struct usb_hcd *hcd)
2379 {
2380         struct usb_device *rhdev = hcd->self.root_hub;
2381
2382         dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2383
2384         usb_get_dev(rhdev);
2385         sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2386
2387         if (HC_IS_RUNNING (hcd->state))
2388                 hcd->state = HC_STATE_QUIESCING;
2389
2390         dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2391         spin_lock_irq (&hcd_root_hub_lock);
2392         hcd->rh_registered = 0;
2393         spin_unlock_irq (&hcd_root_hub_lock);
2394
2395 #ifdef CONFIG_USB_SUSPEND
2396         cancel_work_sync(&hcd->wakeup_work);
2397 #endif
2398
2399         mutex_lock(&usb_bus_list_lock);
2400         usb_disconnect(&rhdev);         /* Sets rhdev to NULL */
2401         mutex_unlock(&usb_bus_list_lock);
2402
2403         /* Prevent any more root-hub status calls from the timer.
2404          * The HCD might still restart the timer (if a port status change
2405          * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2406          * the hub_status_data() callback.
2407          */
2408         hcd->rh_pollable = 0;
2409         clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2410         del_timer_sync(&hcd->rh_timer);
2411
2412         hcd->driver->stop(hcd);
2413         hcd->state = HC_STATE_HALT;
2414
2415         /* In case the HCD restarted the timer, stop it again. */
2416         clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2417         del_timer_sync(&hcd->rh_timer);
2418
2419         if (hcd->irq >= 0)
2420                 free_irq(hcd->irq, hcd);
2421
2422         usb_put_dev(hcd->self.root_hub);
2423         usb_deregister_bus(&hcd->self);
2424         hcd_buffer_destroy(hcd);
2425 }
2426 EXPORT_SYMBOL_GPL(usb_remove_hcd);
2427
2428 void
2429 usb_hcd_platform_shutdown(struct platform_device* dev)
2430 {
2431         struct usb_hcd *hcd = platform_get_drvdata(dev);
2432
2433         if (hcd->driver->shutdown)
2434                 hcd->driver->shutdown(hcd);
2435 }
2436 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2437
2438 /*-------------------------------------------------------------------------*/
2439
2440 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
2441
2442 struct usb_mon_operations *mon_ops;
2443
2444 /*
2445  * The registration is unlocked.
2446  * We do it this way because we do not want to lock in hot paths.
2447  *
2448  * Notice that the code is minimally error-proof. Because usbmon needs
2449  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2450  */
2451
2452 int usb_mon_register (struct usb_mon_operations *ops)
2453 {
2454
2455         if (mon_ops)
2456                 return -EBUSY;
2457
2458         mon_ops = ops;
2459         mb();
2460         return 0;
2461 }
2462 EXPORT_SYMBOL_GPL (usb_mon_register);
2463
2464 void usb_mon_deregister (void)
2465 {
2466
2467         if (mon_ops == NULL) {
2468                 printk(KERN_ERR "USB: monitor was not registered\n");
2469                 return;
2470         }
2471         mon_ops = NULL;
2472         mb();
2473 }
2474 EXPORT_SYMBOL_GPL (usb_mon_deregister);
2475
2476 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */