linux/drivers/usb/core/hcd.c
<<
>>
Prefs
   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/bcd.h>
  26#include <linux/module.h>
  27#include <linux/version.h>
  28#include <linux/kernel.h>
  29#include <linux/sched/task_stack.h>
  30#include <linux/slab.h>
  31#include <linux/completion.h>
  32#include <linux/utsname.h>
  33#include <linux/mm.h>
  34#include <asm/io.h>
  35#include <linux/device.h>
  36#include <linux/dma-mapping.h>
  37#include <linux/mutex.h>
  38#include <asm/irq.h>
  39#include <asm/byteorder.h>
  40#include <asm/unaligned.h>
  41#include <linux/platform_device.h>
  42#include <linux/workqueue.h>
  43#include <linux/pm_runtime.h>
  44#include <linux/types.h>
  45
  46#include <linux/phy/phy.h>
  47#include <linux/usb.h>
  48#include <linux/usb/hcd.h>
  49#include <linux/usb/phy.h>
  50#include <linux/usb/otg.h>
  51
  52#include "usb.h"
  53
  54
  55/*-------------------------------------------------------------------------*/
  56
  57/*
  58 * USB Host Controller Driver framework
  59 *
  60 * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
  61 * HCD-specific behaviors/bugs.
  62 *
  63 * This does error checks, tracks devices and urbs, and delegates to a
  64 * "hc_driver" only for code (and data) that really needs to know about
  65 * hardware differences.  That includes root hub registers, i/o queues,
  66 * and so on ... but as little else as possible.
  67 *
  68 * Shared code includes most of the "root hub" code (these are emulated,
  69 * though each HC's hardware works differently) and PCI glue, plus request
  70 * tracking overhead.  The HCD code should only block on spinlocks or on
  71 * hardware handshaking; blocking on software events (such as other kernel
  72 * threads releasing resources, or completing actions) is all generic.
  73 *
  74 * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
  75 * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
  76 * only by the hub driver ... and that neither should be seen or used by
  77 * usb client device drivers.
  78 *
  79 * Contributors of ideas or unattributed patches include: David Brownell,
  80 * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
  81 *
  82 * HISTORY:
  83 * 2002-02-21   Pull in most of the usb_bus support from usb.c; some
  84 *              associated cleanup.  "usb_hcd" still != "usb_bus".
  85 * 2001-12-12   Initial patch version for Linux 2.5.1 kernel.
  86 */
  87
  88/*-------------------------------------------------------------------------*/
  89
  90/* Keep track of which host controller drivers are loaded */
  91unsigned long usb_hcds_loaded;
  92EXPORT_SYMBOL_GPL(usb_hcds_loaded);
  93
  94/* host controllers we manage */
  95DEFINE_IDR (usb_bus_idr);
  96EXPORT_SYMBOL_GPL (usb_bus_idr);
  97
  98/* used when allocating bus numbers */
  99#define USB_MAXBUS              64
 100
 101/* used when updating list of hcds */
 102DEFINE_MUTEX(usb_bus_idr_lock); /* exported only for usbfs */
 103EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
 104
 105/* used for controlling access to virtual root hubs */
 106static DEFINE_SPINLOCK(hcd_root_hub_lock);
 107
 108/* used when updating an endpoint's URB list */
 109static DEFINE_SPINLOCK(hcd_urb_list_lock);
 110
 111/* used to protect against unlinking URBs after the device is gone */
 112static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
 113
 114/* wait queue for synchronous unlinks */
 115DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
 116
 117static inline int is_root_hub(struct usb_device *udev)
 118{
 119        return (udev->parent == NULL);
 120}
 121
 122/*-------------------------------------------------------------------------*/
 123
 124/*
 125 * Sharable chunks of root hub code.
 126 */
 127
 128/*-------------------------------------------------------------------------*/
 129#define KERNEL_REL      bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
 130#define KERNEL_VER      bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
 131
 132/* usb 3.1 root hub device descriptor */
 133static const u8 usb31_rh_dev_descriptor[18] = {
 134        0x12,       /*  __u8  bLength; */
 135        USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 136        0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
 137
 138        0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 139        0x00,       /*  __u8  bDeviceSubClass; */
 140        0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
 141        0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
 142
 143        0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 144        0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
 145        KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 146
 147        0x03,       /*  __u8  iManufacturer; */
 148        0x02,       /*  __u8  iProduct; */
 149        0x01,       /*  __u8  iSerialNumber; */
 150        0x01        /*  __u8  bNumConfigurations; */
 151};
 152
 153/* usb 3.0 root hub device descriptor */
 154static const u8 usb3_rh_dev_descriptor[18] = {
 155        0x12,       /*  __u8  bLength; */
 156        USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 157        0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
 158
 159        0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 160        0x00,       /*  __u8  bDeviceSubClass; */
 161        0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
 162        0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
 163
 164        0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 165        0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
 166        KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 167
 168        0x03,       /*  __u8  iManufacturer; */
 169        0x02,       /*  __u8  iProduct; */
 170        0x01,       /*  __u8  iSerialNumber; */
 171        0x01        /*  __u8  bNumConfigurations; */
 172};
 173
 174/* usb 2.5 (wireless USB 1.0) root hub device descriptor */
 175static const u8 usb25_rh_dev_descriptor[18] = {
 176        0x12,       /*  __u8  bLength; */
 177        USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 178        0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
 179
 180        0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 181        0x00,       /*  __u8  bDeviceSubClass; */
 182        0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 183        0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
 184
 185        0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 186        0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 187        KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 188
 189        0x03,       /*  __u8  iManufacturer; */
 190        0x02,       /*  __u8  iProduct; */
 191        0x01,       /*  __u8  iSerialNumber; */
 192        0x01        /*  __u8  bNumConfigurations; */
 193};
 194
 195/* usb 2.0 root hub device descriptor */
 196static const u8 usb2_rh_dev_descriptor[18] = {
 197        0x12,       /*  __u8  bLength; */
 198        USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 199        0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
 200
 201        0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 202        0x00,       /*  __u8  bDeviceSubClass; */
 203        0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 204        0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 205
 206        0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 207        0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 208        KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 209
 210        0x03,       /*  __u8  iManufacturer; */
 211        0x02,       /*  __u8  iProduct; */
 212        0x01,       /*  __u8  iSerialNumber; */
 213        0x01        /*  __u8  bNumConfigurations; */
 214};
 215
 216/* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
 217
 218/* usb 1.1 root hub device descriptor */
 219static const u8 usb11_rh_dev_descriptor[18] = {
 220        0x12,       /*  __u8  bLength; */
 221        USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 222        0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
 223
 224        0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 225        0x00,       /*  __u8  bDeviceSubClass; */
 226        0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
 227        0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 228
 229        0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 230        0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
 231        KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 232
 233        0x03,       /*  __u8  iManufacturer; */
 234        0x02,       /*  __u8  iProduct; */
 235        0x01,       /*  __u8  iSerialNumber; */
 236        0x01        /*  __u8  bNumConfigurations; */
 237};
 238
 239
 240/*-------------------------------------------------------------------------*/
 241
 242/* Configuration descriptors for our root hubs */
 243
 244static const u8 fs_rh_config_descriptor[] = {
 245
 246        /* one configuration */
 247        0x09,       /*  __u8  bLength; */
 248        USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 249        0x19, 0x00, /*  __le16 wTotalLength; */
 250        0x01,       /*  __u8  bNumInterfaces; (1) */
 251        0x01,       /*  __u8  bConfigurationValue; */
 252        0x00,       /*  __u8  iConfiguration; */
 253        0xc0,       /*  __u8  bmAttributes;
 254                                 Bit 7: must be set,
 255                                     6: Self-powered,
 256                                     5: Remote wakeup,
 257                                     4..0: resvd */
 258        0x00,       /*  __u8  MaxPower; */
 259
 260        /* USB 1.1:
 261         * USB 2.0, single TT organization (mandatory):
 262         *      one interface, protocol 0
 263         *
 264         * USB 2.0, multiple TT organization (optional):
 265         *      two interfaces, protocols 1 (like single TT)
 266         *      and 2 (multiple TT mode) ... config is
 267         *      sometimes settable
 268         *      NOT IMPLEMENTED
 269         */
 270
 271        /* one interface */
 272        0x09,       /*  __u8  if_bLength; */
 273        USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
 274        0x00,       /*  __u8  if_bInterfaceNumber; */
 275        0x00,       /*  __u8  if_bAlternateSetting; */
 276        0x01,       /*  __u8  if_bNumEndpoints; */
 277        0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 278        0x00,       /*  __u8  if_bInterfaceSubClass; */
 279        0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 280        0x00,       /*  __u8  if_iInterface; */
 281
 282        /* one endpoint (status change endpoint) */
 283        0x07,       /*  __u8  ep_bLength; */
 284        USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 285        0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 286        0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 287        0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
 288        0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
 289};
 290
 291static const u8 hs_rh_config_descriptor[] = {
 292
 293        /* one configuration */
 294        0x09,       /*  __u8  bLength; */
 295        USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 296        0x19, 0x00, /*  __le16 wTotalLength; */
 297        0x01,       /*  __u8  bNumInterfaces; (1) */
 298        0x01,       /*  __u8  bConfigurationValue; */
 299        0x00,       /*  __u8  iConfiguration; */
 300        0xc0,       /*  __u8  bmAttributes;
 301                                 Bit 7: must be set,
 302                                     6: Self-powered,
 303                                     5: Remote wakeup,
 304                                     4..0: resvd */
 305        0x00,       /*  __u8  MaxPower; */
 306
 307        /* USB 1.1:
 308         * USB 2.0, single TT organization (mandatory):
 309         *      one interface, protocol 0
 310         *
 311         * USB 2.0, multiple TT organization (optional):
 312         *      two interfaces, protocols 1 (like single TT)
 313         *      and 2 (multiple TT mode) ... config is
 314         *      sometimes settable
 315         *      NOT IMPLEMENTED
 316         */
 317
 318        /* one interface */
 319        0x09,       /*  __u8  if_bLength; */
 320        USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
 321        0x00,       /*  __u8  if_bInterfaceNumber; */
 322        0x00,       /*  __u8  if_bAlternateSetting; */
 323        0x01,       /*  __u8  if_bNumEndpoints; */
 324        0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 325        0x00,       /*  __u8  if_bInterfaceSubClass; */
 326        0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 327        0x00,       /*  __u8  if_iInterface; */
 328
 329        /* one endpoint (status change endpoint) */
 330        0x07,       /*  __u8  ep_bLength; */
 331        USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 332        0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 333        0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 334                    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 335                     * see hub.c:hub_configure() for details. */
 336        (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 337        0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 338};
 339
 340static const u8 ss_rh_config_descriptor[] = {
 341        /* one configuration */
 342        0x09,       /*  __u8  bLength; */
 343        USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 344        0x1f, 0x00, /*  __le16 wTotalLength; */
 345        0x01,       /*  __u8  bNumInterfaces; (1) */
 346        0x01,       /*  __u8  bConfigurationValue; */
 347        0x00,       /*  __u8  iConfiguration; */
 348        0xc0,       /*  __u8  bmAttributes;
 349                                 Bit 7: must be set,
 350                                     6: Self-powered,
 351                                     5: Remote wakeup,
 352                                     4..0: resvd */
 353        0x00,       /*  __u8  MaxPower; */
 354
 355        /* one interface */
 356        0x09,       /*  __u8  if_bLength; */
 357        USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
 358        0x00,       /*  __u8  if_bInterfaceNumber; */
 359        0x00,       /*  __u8  if_bAlternateSetting; */
 360        0x01,       /*  __u8  if_bNumEndpoints; */
 361        0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 362        0x00,       /*  __u8  if_bInterfaceSubClass; */
 363        0x00,       /*  __u8  if_bInterfaceProtocol; */
 364        0x00,       /*  __u8  if_iInterface; */
 365
 366        /* one endpoint (status change endpoint) */
 367        0x07,       /*  __u8  ep_bLength; */
 368        USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 369        0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 370        0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 371                    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 372                     * see hub.c:hub_configure() for details. */
 373        (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 374        0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 375
 376        /* one SuperSpeed endpoint companion descriptor */
 377        0x06,        /* __u8 ss_bLength */
 378        USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
 379                     /* Companion */
 380        0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
 381        0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
 382        0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
 383};
 384
 385/* authorized_default behaviour:
 386 * -1 is authorized for all devices except wireless (old behaviour)
 387 * 0 is unauthorized for all devices
 388 * 1 is authorized for all devices
 389 */
 390static int authorized_default = -1;
 391module_param(authorized_default, int, S_IRUGO|S_IWUSR);
 392MODULE_PARM_DESC(authorized_default,
 393                "Default USB device authorization: 0 is not authorized, 1 is "
 394                "authorized, -1 is authorized except for wireless USB (default, "
 395                "old behaviour");
 396/*-------------------------------------------------------------------------*/
 397
 398/**
 399 * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
 400 * @s: Null-terminated ASCII (actually ISO-8859-1) string
 401 * @buf: Buffer for USB string descriptor (header + UTF-16LE)
 402 * @len: Length (in bytes; may be odd) of descriptor buffer.
 403 *
 404 * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
 405 * whichever is less.
 406 *
 407 * Note:
 408 * USB String descriptors can contain at most 126 characters; input
 409 * strings longer than that are truncated.
 410 */
 411static unsigned
 412ascii2desc(char const *s, u8 *buf, unsigned len)
 413{
 414        unsigned n, t = 2 + 2*strlen(s);
 415
 416        if (t > 254)
 417                t = 254;        /* Longest possible UTF string descriptor */
 418        if (len > t)
 419                len = t;
 420
 421        t += USB_DT_STRING << 8;        /* Now t is first 16 bits to store */
 422
 423        n = len;
 424        while (n--) {
 425                *buf++ = t;
 426                if (!n--)
 427                        break;
 428                *buf++ = t >> 8;
 429                t = (unsigned char)*s++;
 430        }
 431        return len;
 432}
 433
 434/**
 435 * rh_string() - provides string descriptors for root hub
 436 * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
 437 * @hcd: the host controller for this root hub
 438 * @data: buffer for output packet
 439 * @len: length of the provided buffer
 440 *
 441 * Produces either a manufacturer, product or serial number string for the
 442 * virtual root hub device.
 443 *
 444 * Return: The number of bytes filled in: the length of the descriptor or
 445 * of the provided buffer, whichever is less.
 446 */
 447static unsigned
 448rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
 449{
 450        char buf[100];
 451        char const *s;
 452        static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
 453
 454        /* language ids */
 455        switch (id) {
 456        case 0:
 457                /* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
 458                /* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
 459                if (len > 4)
 460                        len = 4;
 461                memcpy(data, langids, len);
 462                return len;
 463        case 1:
 464                /* Serial number */
 465                s = hcd->self.bus_name;
 466                break;
 467        case 2:
 468                /* Product name */
 469                s = hcd->product_desc;
 470                break;
 471        case 3:
 472                /* Manufacturer */
 473                snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
 474                        init_utsname()->release, hcd->driver->description);
 475                s = buf;
 476                break;
 477        default:
 478                /* Can't happen; caller guarantees it */
 479                return 0;
 480        }
 481
 482        return ascii2desc(s, data, len);
 483}
 484
 485
 486/* Root hub control transfers execute synchronously */
 487static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
 488{
 489        struct usb_ctrlrequest *cmd;
 490        u16             typeReq, wValue, wIndex, wLength;
 491        u8              *ubuf = urb->transfer_buffer;
 492        unsigned        len = 0;
 493        int             status;
 494        u8              patch_wakeup = 0;
 495        u8              patch_protocol = 0;
 496        u16             tbuf_size;
 497        u8              *tbuf = NULL;
 498        const u8        *bufp;
 499
 500        might_sleep();
 501
 502        spin_lock_irq(&hcd_root_hub_lock);
 503        status = usb_hcd_link_urb_to_ep(hcd, urb);
 504        spin_unlock_irq(&hcd_root_hub_lock);
 505        if (status)
 506                return status;
 507        urb->hcpriv = hcd;      /* Indicate it's queued */
 508
 509        cmd = (struct usb_ctrlrequest *) urb->setup_packet;
 510        typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
 511        wValue   = le16_to_cpu (cmd->wValue);
 512        wIndex   = le16_to_cpu (cmd->wIndex);
 513        wLength  = le16_to_cpu (cmd->wLength);
 514
 515        if (wLength > urb->transfer_buffer_length)
 516                goto error;
 517
 518        /*
 519         * tbuf should be at least as big as the
 520         * USB hub descriptor.
 521         */
 522        tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
 523        tbuf = kzalloc(tbuf_size, GFP_KERNEL);
 524        if (!tbuf) {
 525                status = -ENOMEM;
 526                goto err_alloc;
 527        }
 528
 529        bufp = tbuf;
 530
 531
 532        urb->actual_length = 0;
 533        switch (typeReq) {
 534
 535        /* DEVICE REQUESTS */
 536
 537        /* The root hub's remote wakeup enable bit is implemented using
 538         * driver model wakeup flags.  If this system supports wakeup
 539         * through USB, userspace may change the default "allow wakeup"
 540         * policy through sysfs or these calls.
 541         *
 542         * Most root hubs support wakeup from downstream devices, for
 543         * runtime power management (disabling USB clocks and reducing
 544         * VBUS power usage).  However, not all of them do so; silicon,
 545         * board, and BIOS bugs here are not uncommon, so these can't
 546         * be treated quite like external hubs.
 547         *
 548         * Likewise, not all root hubs will pass wakeup events upstream,
 549         * to wake up the whole system.  So don't assume root hub and
 550         * controller capabilities are identical.
 551         */
 552
 553        case DeviceRequest | USB_REQ_GET_STATUS:
 554                tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
 555                                        << USB_DEVICE_REMOTE_WAKEUP)
 556                                | (1 << USB_DEVICE_SELF_POWERED);
 557                tbuf[1] = 0;
 558                len = 2;
 559                break;
 560        case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
 561                if (wValue == USB_DEVICE_REMOTE_WAKEUP)
 562                        device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
 563                else
 564                        goto error;
 565                break;
 566        case DeviceOutRequest | USB_REQ_SET_FEATURE:
 567                if (device_can_wakeup(&hcd->self.root_hub->dev)
 568                                && wValue == USB_DEVICE_REMOTE_WAKEUP)
 569                        device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
 570                else
 571                        goto error;
 572                break;
 573        case DeviceRequest | USB_REQ_GET_CONFIGURATION:
 574                tbuf[0] = 1;
 575                len = 1;
 576                        /* FALLTHROUGH */
 577        case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
 578                break;
 579        case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 580                switch (wValue & 0xff00) {
 581                case USB_DT_DEVICE << 8:
 582                        switch (hcd->speed) {
 583                        case HCD_USB31:
 584                                bufp = usb31_rh_dev_descriptor;
 585                                break;
 586                        case HCD_USB3:
 587                                bufp = usb3_rh_dev_descriptor;
 588                                break;
 589                        case HCD_USB25:
 590                                bufp = usb25_rh_dev_descriptor;
 591                                break;
 592                        case HCD_USB2:
 593                                bufp = usb2_rh_dev_descriptor;
 594                                break;
 595                        case HCD_USB11:
 596                                bufp = usb11_rh_dev_descriptor;
 597                                break;
 598                        default:
 599                                goto error;
 600                        }
 601                        len = 18;
 602                        if (hcd->has_tt)
 603                                patch_protocol = 1;
 604                        break;
 605                case USB_DT_CONFIG << 8:
 606                        switch (hcd->speed) {
 607                        case HCD_USB31:
 608                        case HCD_USB3:
 609                                bufp = ss_rh_config_descriptor;
 610                                len = sizeof ss_rh_config_descriptor;
 611                                break;
 612                        case HCD_USB25:
 613                        case HCD_USB2:
 614                                bufp = hs_rh_config_descriptor;
 615                                len = sizeof hs_rh_config_descriptor;
 616                                break;
 617                        case HCD_USB11:
 618                                bufp = fs_rh_config_descriptor;
 619                                len = sizeof fs_rh_config_descriptor;
 620                                break;
 621                        default:
 622                                goto error;
 623                        }
 624                        if (device_can_wakeup(&hcd->self.root_hub->dev))
 625                                patch_wakeup = 1;
 626                        break;
 627                case USB_DT_STRING << 8:
 628                        if ((wValue & 0xff) < 4)
 629                                urb->actual_length = rh_string(wValue & 0xff,
 630                                                hcd, ubuf, wLength);
 631                        else /* unsupported IDs --> "protocol stall" */
 632                                goto error;
 633                        break;
 634                case USB_DT_BOS << 8:
 635                        goto nongeneric;
 636                default:
 637                        goto error;
 638                }
 639                break;
 640        case DeviceRequest | USB_REQ_GET_INTERFACE:
 641                tbuf[0] = 0;
 642                len = 1;
 643                        /* FALLTHROUGH */
 644        case DeviceOutRequest | USB_REQ_SET_INTERFACE:
 645                break;
 646        case DeviceOutRequest | USB_REQ_SET_ADDRESS:
 647                /* wValue == urb->dev->devaddr */
 648                dev_dbg (hcd->self.controller, "root hub device address %d\n",
 649                        wValue);
 650                break;
 651
 652        /* INTERFACE REQUESTS (no defined feature/status flags) */
 653
 654        /* ENDPOINT REQUESTS */
 655
 656        case EndpointRequest | USB_REQ_GET_STATUS:
 657                /* ENDPOINT_HALT flag */
 658                tbuf[0] = 0;
 659                tbuf[1] = 0;
 660                len = 2;
 661                        /* FALLTHROUGH */
 662        case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
 663        case EndpointOutRequest | USB_REQ_SET_FEATURE:
 664                dev_dbg (hcd->self.controller, "no endpoint features yet\n");
 665                break;
 666
 667        /* CLASS REQUESTS (and errors) */
 668
 669        default:
 670nongeneric:
 671                /* non-generic request */
 672                switch (typeReq) {
 673                case GetHubStatus:
 674                        len = 4;
 675                        break;
 676                case GetPortStatus:
 677                        if (wValue == HUB_PORT_STATUS)
 678                                len = 4;
 679                        else
 680                                /* other port status types return 8 bytes */
 681                                len = 8;
 682                        break;
 683                case GetHubDescriptor:
 684                        len = sizeof (struct usb_hub_descriptor);
 685                        break;
 686                case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 687                        /* len is returned by hub_control */
 688                        break;
 689                }
 690                status = hcd->driver->hub_control (hcd,
 691                        typeReq, wValue, wIndex,
 692                        tbuf, wLength);
 693
 694                if (typeReq == GetHubDescriptor)
 695                        usb_hub_adjust_deviceremovable(hcd->self.root_hub,
 696                                (struct usb_hub_descriptor *)tbuf);
 697                break;
 698error:
 699                /* "protocol stall" on error */
 700                status = -EPIPE;
 701        }
 702
 703        if (status < 0) {
 704                len = 0;
 705                if (status != -EPIPE) {
 706                        dev_dbg (hcd->self.controller,
 707                                "CTRL: TypeReq=0x%x val=0x%x "
 708                                "idx=0x%x len=%d ==> %d\n",
 709                                typeReq, wValue, wIndex,
 710                                wLength, status);
 711                }
 712        } else if (status > 0) {
 713                /* hub_control may return the length of data copied. */
 714                len = status;
 715                status = 0;
 716        }
 717        if (len) {
 718                if (urb->transfer_buffer_length < len)
 719                        len = urb->transfer_buffer_length;
 720                urb->actual_length = len;
 721                /* always USB_DIR_IN, toward host */
 722                memcpy (ubuf, bufp, len);
 723
 724                /* report whether RH hardware supports remote wakeup */
 725                if (patch_wakeup &&
 726                                len > offsetof (struct usb_config_descriptor,
 727                                                bmAttributes))
 728                        ((struct usb_config_descriptor *)ubuf)->bmAttributes
 729                                |= USB_CONFIG_ATT_WAKEUP;
 730
 731                /* report whether RH hardware has an integrated TT */
 732                if (patch_protocol &&
 733                                len > offsetof(struct usb_device_descriptor,
 734                                                bDeviceProtocol))
 735                        ((struct usb_device_descriptor *) ubuf)->
 736                                bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
 737        }
 738
 739        kfree(tbuf);
 740 err_alloc:
 741
 742        /* any errors get returned through the urb completion */
 743        spin_lock_irq(&hcd_root_hub_lock);
 744        usb_hcd_unlink_urb_from_ep(hcd, urb);
 745        usb_hcd_giveback_urb(hcd, urb, status);
 746        spin_unlock_irq(&hcd_root_hub_lock);
 747        return 0;
 748}
 749
 750/*-------------------------------------------------------------------------*/
 751
 752/*
 753 * Root Hub interrupt transfers are polled using a timer if the
 754 * driver requests it; otherwise the driver is responsible for
 755 * calling usb_hcd_poll_rh_status() when an event occurs.
 756 *
 757 * Completions are called in_interrupt(), but they may or may not
 758 * be in_irq().
 759 */
 760void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
 761{
 762        struct urb      *urb;
 763        int             length;
 764        unsigned long   flags;
 765        char            buffer[6];      /* Any root hubs with > 31 ports? */
 766
 767        if (unlikely(!hcd->rh_pollable))
 768                return;
 769        if (!hcd->uses_new_polling && !hcd->status_urb)
 770                return;
 771
 772        length = hcd->driver->hub_status_data(hcd, buffer);
 773        if (length > 0) {
 774
 775                /* try to complete the status urb */
 776                spin_lock_irqsave(&hcd_root_hub_lock, flags);
 777                urb = hcd->status_urb;
 778                if (urb) {
 779                        clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 780                        hcd->status_urb = NULL;
 781                        urb->actual_length = length;
 782                        memcpy(urb->transfer_buffer, buffer, length);
 783
 784                        usb_hcd_unlink_urb_from_ep(hcd, urb);
 785                        usb_hcd_giveback_urb(hcd, urb, 0);
 786                } else {
 787                        length = 0;
 788                        set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 789                }
 790                spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 791        }
 792
 793        /* The USB 2.0 spec says 256 ms.  This is close enough and won't
 794         * exceed that limit if HZ is 100. The math is more clunky than
 795         * maybe expected, this is to make sure that all timers for USB devices
 796         * fire at the same time to give the CPU a break in between */
 797        if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
 798                        (length == 0 && hcd->status_urb != NULL))
 799                mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 800}
 801EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
 802
 803/* timer callback */
 804static void rh_timer_func (unsigned long _hcd)
 805{
 806        usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
 807}
 808
 809/*-------------------------------------------------------------------------*/
 810
 811static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
 812{
 813        int             retval;
 814        unsigned long   flags;
 815        unsigned        len = 1 + (urb->dev->maxchild / 8);
 816
 817        spin_lock_irqsave (&hcd_root_hub_lock, flags);
 818        if (hcd->status_urb || urb->transfer_buffer_length < len) {
 819                dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
 820                retval = -EINVAL;
 821                goto done;
 822        }
 823
 824        retval = usb_hcd_link_urb_to_ep(hcd, urb);
 825        if (retval)
 826                goto done;
 827
 828        hcd->status_urb = urb;
 829        urb->hcpriv = hcd;      /* indicate it's queued */
 830        if (!hcd->uses_new_polling)
 831                mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 832
 833        /* If a status change has already occurred, report it ASAP */
 834        else if (HCD_POLL_PENDING(hcd))
 835                mod_timer(&hcd->rh_timer, jiffies);
 836        retval = 0;
 837 done:
 838        spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
 839        return retval;
 840}
 841
 842static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
 843{
 844        if (usb_endpoint_xfer_int(&urb->ep->desc))
 845                return rh_queue_status (hcd, urb);
 846        if (usb_endpoint_xfer_control(&urb->ep->desc))
 847                return rh_call_control (hcd, urb);
 848        return -EINVAL;
 849}
 850
 851/*-------------------------------------------------------------------------*/
 852
 853/* Unlinks of root-hub control URBs are legal, but they don't do anything
 854 * since these URBs always execute synchronously.
 855 */
 856static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 857{
 858        unsigned long   flags;
 859        int             rc;
 860
 861        spin_lock_irqsave(&hcd_root_hub_lock, flags);
 862        rc = usb_hcd_check_unlink_urb(hcd, urb, status);
 863        if (rc)
 864                goto done;
 865
 866        if (usb_endpoint_num(&urb->ep->desc) == 0) {    /* Control URB */
 867                ;       /* Do nothing */
 868
 869        } else {                                /* Status URB */
 870                if (!hcd->uses_new_polling)
 871                        del_timer (&hcd->rh_timer);
 872                if (urb == hcd->status_urb) {
 873                        hcd->status_urb = NULL;
 874                        usb_hcd_unlink_urb_from_ep(hcd, urb);
 875                        usb_hcd_giveback_urb(hcd, urb, status);
 876                }
 877        }
 878 done:
 879        spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 880        return rc;
 881}
 882
 883
 884
 885/*
 886 * Show & store the current value of authorized_default
 887 */
 888static ssize_t authorized_default_show(struct device *dev,
 889                                       struct device_attribute *attr, char *buf)
 890{
 891        struct usb_device *rh_usb_dev = to_usb_device(dev);
 892        struct usb_bus *usb_bus = rh_usb_dev->bus;
 893        struct usb_hcd *hcd;
 894
 895        hcd = bus_to_hcd(usb_bus);
 896        return snprintf(buf, PAGE_SIZE, "%u\n", !!HCD_DEV_AUTHORIZED(hcd));
 897}
 898
 899static ssize_t authorized_default_store(struct device *dev,
 900                                        struct device_attribute *attr,
 901                                        const char *buf, size_t size)
 902{
 903        ssize_t result;
 904        unsigned val;
 905        struct usb_device *rh_usb_dev = to_usb_device(dev);
 906        struct usb_bus *usb_bus = rh_usb_dev->bus;
 907        struct usb_hcd *hcd;
 908
 909        hcd = bus_to_hcd(usb_bus);
 910        result = sscanf(buf, "%u\n", &val);
 911        if (result == 1) {
 912                if (val)
 913                        set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
 914                else
 915                        clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
 916
 917                result = size;
 918        } else {
 919                result = -EINVAL;
 920        }
 921        return result;
 922}
 923static DEVICE_ATTR_RW(authorized_default);
 924
 925/*
 926 * interface_authorized_default_show - show default authorization status
 927 * for USB interfaces
 928 *
 929 * note: interface_authorized_default is the default value
 930 *       for initializing the authorized attribute of interfaces
 931 */
 932static ssize_t interface_authorized_default_show(struct device *dev,
 933                struct device_attribute *attr, char *buf)
 934{
 935        struct usb_device *usb_dev = to_usb_device(dev);
 936        struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
 937
 938        return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
 939}
 940
 941/*
 942 * interface_authorized_default_store - store default authorization status
 943 * for USB interfaces
 944 *
 945 * note: interface_authorized_default is the default value
 946 *       for initializing the authorized attribute of interfaces
 947 */
 948static ssize_t interface_authorized_default_store(struct device *dev,
 949                struct device_attribute *attr, const char *buf, size_t count)
 950{
 951        struct usb_device *usb_dev = to_usb_device(dev);
 952        struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
 953        int rc = count;
 954        bool val;
 955
 956        if (strtobool(buf, &val) != 0)
 957                return -EINVAL;
 958
 959        if (val)
 960                set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
 961        else
 962                clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
 963
 964        return rc;
 965}
 966static DEVICE_ATTR_RW(interface_authorized_default);
 967
 968/* Group all the USB bus attributes */
 969static struct attribute *usb_bus_attrs[] = {
 970                &dev_attr_authorized_default.attr,
 971                &dev_attr_interface_authorized_default.attr,
 972                NULL,
 973};
 974
 975static struct attribute_group usb_bus_attr_group = {
 976        .name = NULL,   /* we want them in the same directory */
 977        .attrs = usb_bus_attrs,
 978};
 979
 980
 981
 982/*-------------------------------------------------------------------------*/
 983
 984/**
 985 * usb_bus_init - shared initialization code
 986 * @bus: the bus structure being initialized
 987 *
 988 * This code is used to initialize a usb_bus structure, memory for which is
 989 * separately managed.
 990 */
 991static void usb_bus_init (struct usb_bus *bus)
 992{
 993        memset (&bus->devmap, 0, sizeof(struct usb_devmap));
 994
 995        bus->devnum_next = 1;
 996
 997        bus->root_hub = NULL;
 998        bus->busnum = -1;
 999        bus->bandwidth_allocated = 0;
1000        bus->bandwidth_int_reqs  = 0;
1001        bus->bandwidth_isoc_reqs = 0;
1002        mutex_init(&bus->devnum_next_mutex);
1003}
1004
1005/*-------------------------------------------------------------------------*/
1006
1007/**
1008 * usb_register_bus - registers the USB host controller with the usb core
1009 * @bus: pointer to the bus to register
1010 * Context: !in_interrupt()
1011 *
1012 * Assigns a bus number, and links the controller into usbcore data
1013 * structures so that it can be seen by scanning the bus list.
1014 *
1015 * Return: 0 if successful. A negative error code otherwise.
1016 */
1017static int usb_register_bus(struct usb_bus *bus)
1018{
1019        int result = -E2BIG;
1020        int busnum;
1021
1022        mutex_lock(&usb_bus_idr_lock);
1023        busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
1024        if (busnum < 0) {
1025                pr_err("%s: failed to get bus number\n", usbcore_name);
1026                goto error_find_busnum;
1027        }
1028        bus->busnum = busnum;
1029        mutex_unlock(&usb_bus_idr_lock);
1030
1031        usb_notify_add_bus(bus);
1032
1033        dev_info (bus->controller, "new USB bus registered, assigned bus "
1034                  "number %d\n", bus->busnum);
1035        return 0;
1036
1037error_find_busnum:
1038        mutex_unlock(&usb_bus_idr_lock);
1039        return result;
1040}
1041
1042/**
1043 * usb_deregister_bus - deregisters the USB host controller
1044 * @bus: pointer to the bus to deregister
1045 * Context: !in_interrupt()
1046 *
1047 * Recycles the bus number, and unlinks the controller from usbcore data
1048 * structures so that it won't be seen by scanning the bus list.
1049 */
1050static void usb_deregister_bus (struct usb_bus *bus)
1051{
1052        dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
1053
1054        /*
1055         * NOTE: make sure that all the devices are removed by the
1056         * controller code, as well as having it call this when cleaning
1057         * itself up
1058         */
1059        mutex_lock(&usb_bus_idr_lock);
1060        idr_remove(&usb_bus_idr, bus->busnum);
1061        mutex_unlock(&usb_bus_idr_lock);
1062
1063        usb_notify_remove_bus(bus);
1064}
1065
1066/**
1067 * register_root_hub - called by usb_add_hcd() to register a root hub
1068 * @hcd: host controller for this root hub
1069 *
1070 * This function registers the root hub with the USB subsystem.  It sets up
1071 * the device properly in the device tree and then calls usb_new_device()
1072 * to register the usb device.  It also assigns the root hub's USB address
1073 * (always 1).
1074 *
1075 * Return: 0 if successful. A negative error code otherwise.
1076 */
1077static int register_root_hub(struct usb_hcd *hcd)
1078{
1079        struct device *parent_dev = hcd->self.controller;
1080        struct usb_device *usb_dev = hcd->self.root_hub;
1081        const int devnum = 1;
1082        int retval;
1083
1084        usb_dev->devnum = devnum;
1085        usb_dev->bus->devnum_next = devnum + 1;
1086        memset (&usb_dev->bus->devmap.devicemap, 0,
1087                        sizeof usb_dev->bus->devmap.devicemap);
1088        set_bit (devnum, usb_dev->bus->devmap.devicemap);
1089        usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1090
1091        mutex_lock(&usb_bus_idr_lock);
1092
1093        usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1094        retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1095        if (retval != sizeof usb_dev->descriptor) {
1096                mutex_unlock(&usb_bus_idr_lock);
1097                dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1098                                dev_name(&usb_dev->dev), retval);
1099                return (retval < 0) ? retval : -EMSGSIZE;
1100        }
1101
1102        if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
1103                retval = usb_get_bos_descriptor(usb_dev);
1104                if (!retval) {
1105                        usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1106                } else if (usb_dev->speed >= USB_SPEED_SUPER) {
1107                        mutex_unlock(&usb_bus_idr_lock);
1108                        dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1109                                        dev_name(&usb_dev->dev), retval);
1110                        return retval;
1111                }
1112        }
1113
1114        retval = usb_new_device (usb_dev);
1115        if (retval) {
1116                dev_err (parent_dev, "can't register root hub for %s, %d\n",
1117                                dev_name(&usb_dev->dev), retval);
1118        } else {
1119                spin_lock_irq (&hcd_root_hub_lock);
1120                hcd->rh_registered = 1;
1121                spin_unlock_irq (&hcd_root_hub_lock);
1122
1123                /* Did the HC die before the root hub was registered? */
1124                if (HCD_DEAD(hcd))
1125                        usb_hc_died (hcd);      /* This time clean up */
1126        }
1127        mutex_unlock(&usb_bus_idr_lock);
1128
1129        return retval;
1130}
1131
1132/*
1133 * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1134 * @bus: the bus which the root hub belongs to
1135 * @portnum: the port which is being resumed
1136 *
1137 * HCDs should call this function when they know that a resume signal is
1138 * being sent to a root-hub port.  The root hub will be prevented from
1139 * going into autosuspend until usb_hcd_end_port_resume() is called.
1140 *
1141 * The bus's private lock must be held by the caller.
1142 */
1143void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1144{
1145        unsigned bit = 1 << portnum;
1146
1147        if (!(bus->resuming_ports & bit)) {
1148                bus->resuming_ports |= bit;
1149                pm_runtime_get_noresume(&bus->root_hub->dev);
1150        }
1151}
1152EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1153
1154/*
1155 * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1156 * @bus: the bus which the root hub belongs to
1157 * @portnum: the port which is being resumed
1158 *
1159 * HCDs should call this function when they know that a resume signal has
1160 * stopped being sent to a root-hub port.  The root hub will be allowed to
1161 * autosuspend again.
1162 *
1163 * The bus's private lock must be held by the caller.
1164 */
1165void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1166{
1167        unsigned bit = 1 << portnum;
1168
1169        if (bus->resuming_ports & bit) {
1170                bus->resuming_ports &= ~bit;
1171                pm_runtime_put_noidle(&bus->root_hub->dev);
1172        }
1173}
1174EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1175
1176/*-------------------------------------------------------------------------*/
1177
1178/**
1179 * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1180 * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1181 * @is_input: true iff the transaction sends data to the host
1182 * @isoc: true for isochronous transactions, false for interrupt ones
1183 * @bytecount: how many bytes in the transaction.
1184 *
1185 * Return: Approximate bus time in nanoseconds for a periodic transaction.
1186 *
1187 * Note:
1188 * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1189 * scheduled in software, this function is only used for such scheduling.
1190 */
1191long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1192{
1193        unsigned long   tmp;
1194
1195        switch (speed) {
1196        case USB_SPEED_LOW:     /* INTR only */
1197                if (is_input) {
1198                        tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1199                        return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1200                } else {
1201                        tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1202                        return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1203                }
1204        case USB_SPEED_FULL:    /* ISOC or INTR */
1205                if (isoc) {
1206                        tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1207                        return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1208                } else {
1209                        tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1210                        return 9107L + BW_HOST_DELAY + tmp;
1211                }
1212        case USB_SPEED_HIGH:    /* ISOC or INTR */
1213                /* FIXME adjust for input vs output */
1214                if (isoc)
1215                        tmp = HS_NSECS_ISO (bytecount);
1216                else
1217                        tmp = HS_NSECS (bytecount);
1218                return tmp;
1219        default:
1220                pr_debug ("%s: bogus device speed!\n", usbcore_name);
1221                return -1;
1222        }
1223}
1224EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1225
1226
1227/*-------------------------------------------------------------------------*/
1228
1229/*
1230 * Generic HC operations.
1231 */
1232
1233/*-------------------------------------------------------------------------*/
1234
1235/**
1236 * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1237 * @hcd: host controller to which @urb was submitted
1238 * @urb: URB being submitted
1239 *
1240 * Host controller drivers should call this routine in their enqueue()
1241 * method.  The HCD's private spinlock must be held and interrupts must
1242 * be disabled.  The actions carried out here are required for URB
1243 * submission, as well as for endpoint shutdown and for usb_kill_urb.
1244 *
1245 * Return: 0 for no error, otherwise a negative error code (in which case
1246 * the enqueue() method must fail).  If no error occurs but enqueue() fails
1247 * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1248 * the private spinlock and returning.
1249 */
1250int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1251{
1252        int             rc = 0;
1253
1254        spin_lock(&hcd_urb_list_lock);
1255
1256        /* Check that the URB isn't being killed */
1257        if (unlikely(atomic_read(&urb->reject))) {
1258                rc = -EPERM;
1259                goto done;
1260        }
1261
1262        if (unlikely(!urb->ep->enabled)) {
1263                rc = -ENOENT;
1264                goto done;
1265        }
1266
1267        if (unlikely(!urb->dev->can_submit)) {
1268                rc = -EHOSTUNREACH;
1269                goto done;
1270        }
1271
1272        /*
1273         * Check the host controller's state and add the URB to the
1274         * endpoint's queue.
1275         */
1276        if (HCD_RH_RUNNING(hcd)) {
1277                urb->unlinked = 0;
1278                list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1279        } else {
1280                rc = -ESHUTDOWN;
1281                goto done;
1282        }
1283 done:
1284        spin_unlock(&hcd_urb_list_lock);
1285        return rc;
1286}
1287EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1288
1289/**
1290 * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1291 * @hcd: host controller to which @urb was submitted
1292 * @urb: URB being checked for unlinkability
1293 * @status: error code to store in @urb if the unlink succeeds
1294 *
1295 * Host controller drivers should call this routine in their dequeue()
1296 * method.  The HCD's private spinlock must be held and interrupts must
1297 * be disabled.  The actions carried out here are required for making
1298 * sure than an unlink is valid.
1299 *
1300 * Return: 0 for no error, otherwise a negative error code (in which case
1301 * the dequeue() method must fail).  The possible error codes are:
1302 *
1303 *      -EIDRM: @urb was not submitted or has already completed.
1304 *              The completion function may not have been called yet.
1305 *
1306 *      -EBUSY: @urb has already been unlinked.
1307 */
1308int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1309                int status)
1310{
1311        struct list_head        *tmp;
1312
1313        /* insist the urb is still queued */
1314        list_for_each(tmp, &urb->ep->urb_list) {
1315                if (tmp == &urb->urb_list)
1316                        break;
1317        }
1318        if (tmp != &urb->urb_list)
1319                return -EIDRM;
1320
1321        /* Any status except -EINPROGRESS means something already started to
1322         * unlink this URB from the hardware.  So there's no more work to do.
1323         */
1324        if (urb->unlinked)
1325                return -EBUSY;
1326        urb->unlinked = status;
1327        return 0;
1328}
1329EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1330
1331/**
1332 * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1333 * @hcd: host controller to which @urb was submitted
1334 * @urb: URB being unlinked
1335 *
1336 * Host controller drivers should call this routine before calling
1337 * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1338 * interrupts must be disabled.  The actions carried out here are required
1339 * for URB completion.
1340 */
1341void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1342{
1343        /* clear all state linking urb to this dev (and hcd) */
1344        spin_lock(&hcd_urb_list_lock);
1345        list_del_init(&urb->urb_list);
1346        spin_unlock(&hcd_urb_list_lock);
1347}
1348EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1349
1350/*
1351 * Some usb host controllers can only perform dma using a small SRAM area.
1352 * The usb core itself is however optimized for host controllers that can dma
1353 * using regular system memory - like pci devices doing bus mastering.
1354 *
1355 * To support host controllers with limited dma capabilities we provide dma
1356 * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1357 * For this to work properly the host controller code must first use the
1358 * function dma_declare_coherent_memory() to point out which memory area
1359 * that should be used for dma allocations.
1360 *
1361 * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1362 * dma using dma_alloc_coherent() which in turn allocates from the memory
1363 * area pointed out with dma_declare_coherent_memory().
1364 *
1365 * So, to summarize...
1366 *
1367 * - We need "local" memory, canonical example being
1368 *   a small SRAM on a discrete controller being the
1369 *   only memory that the controller can read ...
1370 *   (a) "normal" kernel memory is no good, and
1371 *   (b) there's not enough to share
1372 *
1373 * - The only *portable* hook for such stuff in the
1374 *   DMA framework is dma_declare_coherent_memory()
1375 *
1376 * - So we use that, even though the primary requirement
1377 *   is that the memory be "local" (hence addressable
1378 *   by that device), not "coherent".
1379 *
1380 */
1381
1382static int hcd_alloc_coherent(struct usb_bus *bus,
1383                              gfp_t mem_flags, dma_addr_t *dma_handle,
1384                              void **vaddr_handle, size_t size,
1385                              enum dma_data_direction dir)
1386{
1387        unsigned char *vaddr;
1388
1389        if (*vaddr_handle == NULL) {
1390                WARN_ON_ONCE(1);
1391                return -EFAULT;
1392        }
1393
1394        vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1395                                 mem_flags, dma_handle);
1396        if (!vaddr)
1397                return -ENOMEM;
1398
1399        /*
1400         * Store the virtual address of the buffer at the end
1401         * of the allocated dma buffer. The size of the buffer
1402         * may be uneven so use unaligned functions instead
1403         * of just rounding up. It makes sense to optimize for
1404         * memory footprint over access speed since the amount
1405         * of memory available for dma may be limited.
1406         */
1407        put_unaligned((unsigned long)*vaddr_handle,
1408                      (unsigned long *)(vaddr + size));
1409
1410        if (dir == DMA_TO_DEVICE)
1411                memcpy(vaddr, *vaddr_handle, size);
1412
1413        *vaddr_handle = vaddr;
1414        return 0;
1415}
1416
1417static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1418                              void **vaddr_handle, size_t size,
1419                              enum dma_data_direction dir)
1420{
1421        unsigned char *vaddr = *vaddr_handle;
1422
1423        vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1424
1425        if (dir == DMA_FROM_DEVICE)
1426                memcpy(vaddr, *vaddr_handle, size);
1427
1428        hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1429
1430        *vaddr_handle = vaddr;
1431        *dma_handle = 0;
1432}
1433
1434void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1435{
1436        if (IS_ENABLED(CONFIG_HAS_DMA) &&
1437            (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1438                dma_unmap_single(hcd->self.sysdev,
1439                                urb->setup_dma,
1440                                sizeof(struct usb_ctrlrequest),
1441                                DMA_TO_DEVICE);
1442        else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1443                hcd_free_coherent(urb->dev->bus,
1444                                &urb->setup_dma,
1445                                (void **) &urb->setup_packet,
1446                                sizeof(struct usb_ctrlrequest),
1447                                DMA_TO_DEVICE);
1448
1449        /* Make it safe to call this routine more than once */
1450        urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1451}
1452EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1453
1454static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1455{
1456        if (hcd->driver->unmap_urb_for_dma)
1457                hcd->driver->unmap_urb_for_dma(hcd, urb);
1458        else
1459                usb_hcd_unmap_urb_for_dma(hcd, urb);
1460}
1461
1462void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1463{
1464        enum dma_data_direction dir;
1465
1466        usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1467
1468        dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1469        if (IS_ENABLED(CONFIG_HAS_DMA) &&
1470            (urb->transfer_flags & URB_DMA_MAP_SG))
1471                dma_unmap_sg(hcd->self.sysdev,
1472                                urb->sg,
1473                                urb->num_sgs,
1474                                dir);
1475        else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1476                 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1477                dma_unmap_page(hcd->self.sysdev,
1478                                urb->transfer_dma,
1479                                urb->transfer_buffer_length,
1480                                dir);
1481        else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1482                 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1483                dma_unmap_single(hcd->self.sysdev,
1484                                urb->transfer_dma,
1485                                urb->transfer_buffer_length,
1486                                dir);
1487        else if (urb->transfer_flags & URB_MAP_LOCAL)
1488                hcd_free_coherent(urb->dev->bus,
1489                                &urb->transfer_dma,
1490                                &urb->transfer_buffer,
1491                                urb->transfer_buffer_length,
1492                                dir);
1493
1494        /* Make it safe to call this routine more than once */
1495        urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1496                        URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1497}
1498EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1499
1500static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1501                           gfp_t mem_flags)
1502{
1503        if (hcd->driver->map_urb_for_dma)
1504                return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1505        else
1506                return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1507}
1508
1509int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1510                            gfp_t mem_flags)
1511{
1512        enum dma_data_direction dir;
1513        int ret = 0;
1514
1515        /* Map the URB's buffers for DMA access.
1516         * Lower level HCD code should use *_dma exclusively,
1517         * unless it uses pio or talks to another transport,
1518         * or uses the provided scatter gather list for bulk.
1519         */
1520
1521        if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1522                if (hcd->self.uses_pio_for_control)
1523                        return ret;
1524                if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1525                        if (is_vmalloc_addr(urb->setup_packet)) {
1526                                WARN_ONCE(1, "setup packet is not dma capable\n");
1527                                return -EAGAIN;
1528                        } else if (object_is_on_stack(urb->setup_packet)) {
1529                                WARN_ONCE(1, "setup packet is on stack\n");
1530                                return -EAGAIN;
1531                        }
1532
1533                        urb->setup_dma = dma_map_single(
1534                                        hcd->self.sysdev,
1535                                        urb->setup_packet,
1536                                        sizeof(struct usb_ctrlrequest),
1537                                        DMA_TO_DEVICE);
1538                        if (dma_mapping_error(hcd->self.sysdev,
1539                                                urb->setup_dma))
1540                                return -EAGAIN;
1541                        urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1542                } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1543                        ret = hcd_alloc_coherent(
1544                                        urb->dev->bus, mem_flags,
1545                                        &urb->setup_dma,
1546                                        (void **)&urb->setup_packet,
1547                                        sizeof(struct usb_ctrlrequest),
1548                                        DMA_TO_DEVICE);
1549                        if (ret)
1550                                return ret;
1551                        urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1552                }
1553        }
1554
1555        dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1556        if (urb->transfer_buffer_length != 0
1557            && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1558                if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1559                        if (urb->num_sgs) {
1560                                int n;
1561
1562                                /* We don't support sg for isoc transfers ! */
1563                                if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1564                                        WARN_ON(1);
1565                                        return -EINVAL;
1566                                }
1567
1568                                n = dma_map_sg(
1569                                                hcd->self.sysdev,
1570                                                urb->sg,
1571                                                urb->num_sgs,
1572                                                dir);
1573                                if (n <= 0)
1574                                        ret = -EAGAIN;
1575                                else
1576                                        urb->transfer_flags |= URB_DMA_MAP_SG;
1577                                urb->num_mapped_sgs = n;
1578                                if (n != urb->num_sgs)
1579                                        urb->transfer_flags |=
1580                                                        URB_DMA_SG_COMBINED;
1581                        } else if (urb->sg) {
1582                                struct scatterlist *sg = urb->sg;
1583                                urb->transfer_dma = dma_map_page(
1584                                                hcd->self.sysdev,
1585                                                sg_page(sg),
1586                                                sg->offset,
1587                                                urb->transfer_buffer_length,
1588                                                dir);
1589                                if (dma_mapping_error(hcd->self.sysdev,
1590                                                urb->transfer_dma))
1591                                        ret = -EAGAIN;
1592                                else
1593                                        urb->transfer_flags |= URB_DMA_MAP_PAGE;
1594                        } else if (is_vmalloc_addr(urb->transfer_buffer)) {
1595                                WARN_ONCE(1, "transfer buffer not dma capable\n");
1596                                ret = -EAGAIN;
1597                        } else if (object_is_on_stack(urb->transfer_buffer)) {
1598                                WARN_ONCE(1, "transfer buffer is on stack\n");
1599                                ret = -EAGAIN;
1600                        } else {
1601                                urb->transfer_dma = dma_map_single(
1602                                                hcd->self.sysdev,
1603                                                urb->transfer_buffer,
1604                                                urb->transfer_buffer_length,
1605                                                dir);
1606                                if (dma_mapping_error(hcd->self.sysdev,
1607                                                urb->transfer_dma))
1608                                        ret = -EAGAIN;
1609                                else
1610                                        urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1611                        }
1612                } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1613                        ret = hcd_alloc_coherent(
1614                                        urb->dev->bus, mem_flags,
1615                                        &urb->transfer_dma,
1616                                        &urb->transfer_buffer,
1617                                        urb->transfer_buffer_length,
1618                                        dir);
1619                        if (ret == 0)
1620                                urb->transfer_flags |= URB_MAP_LOCAL;
1621                }
1622                if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1623                                URB_SETUP_MAP_LOCAL)))
1624                        usb_hcd_unmap_urb_for_dma(hcd, urb);
1625        }
1626        return ret;
1627}
1628EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1629
1630/*-------------------------------------------------------------------------*/
1631
1632/* may be called in any context with a valid urb->dev usecount
1633 * caller surrenders "ownership" of urb
1634 * expects usb_submit_urb() to have sanity checked and conditioned all
1635 * inputs in the urb
1636 */
1637int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1638{
1639        int                     status;
1640        struct usb_hcd          *hcd = bus_to_hcd(urb->dev->bus);
1641
1642        /* increment urb's reference count as part of giving it to the HCD
1643         * (which will control it).  HCD guarantees that it either returns
1644         * an error or calls giveback(), but not both.
1645         */
1646        usb_get_urb(urb);
1647        atomic_inc(&urb->use_count);
1648        atomic_inc(&urb->dev->urbnum);
1649        usbmon_urb_submit(&hcd->self, urb);
1650
1651        /* NOTE requirements on root-hub callers (usbfs and the hub
1652         * driver, for now):  URBs' urb->transfer_buffer must be
1653         * valid and usb_buffer_{sync,unmap}() not be needed, since
1654         * they could clobber root hub response data.  Also, control
1655         * URBs must be submitted in process context with interrupts
1656         * enabled.
1657         */
1658
1659        if (is_root_hub(urb->dev)) {
1660                status = rh_urb_enqueue(hcd, urb);
1661        } else {
1662                status = map_urb_for_dma(hcd, urb, mem_flags);
1663                if (likely(status == 0)) {
1664                        status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1665                        if (unlikely(status))
1666                                unmap_urb_for_dma(hcd, urb);
1667                }
1668        }
1669
1670        if (unlikely(status)) {
1671                usbmon_urb_submit_error(&hcd->self, urb, status);
1672                urb->hcpriv = NULL;
1673                INIT_LIST_HEAD(&urb->urb_list);
1674                atomic_dec(&urb->use_count);
1675                atomic_dec(&urb->dev->urbnum);
1676                if (atomic_read(&urb->reject))
1677                        wake_up(&usb_kill_urb_queue);
1678                usb_put_urb(urb);
1679        }
1680        return status;
1681}
1682
1683/*-------------------------------------------------------------------------*/
1684
1685/* this makes the hcd giveback() the urb more quickly, by kicking it
1686 * off hardware queues (which may take a while) and returning it as
1687 * soon as practical.  we've already set up the urb's return status,
1688 * but we can't know if the callback completed already.
1689 */
1690static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1691{
1692        int             value;
1693
1694        if (is_root_hub(urb->dev))
1695                value = usb_rh_urb_dequeue(hcd, urb, status);
1696        else {
1697
1698                /* The only reason an HCD might fail this call is if
1699                 * it has not yet fully queued the urb to begin with.
1700                 * Such failures should be harmless. */
1701                value = hcd->driver->urb_dequeue(hcd, urb, status);
1702        }
1703        return value;
1704}
1705
1706/*
1707 * called in any context
1708 *
1709 * caller guarantees urb won't be recycled till both unlink()
1710 * and the urb's completion function return
1711 */
1712int usb_hcd_unlink_urb (struct urb *urb, int status)
1713{
1714        struct usb_hcd          *hcd;
1715        struct usb_device       *udev = urb->dev;
1716        int                     retval = -EIDRM;
1717        unsigned long           flags;
1718
1719        /* Prevent the device and bus from going away while
1720         * the unlink is carried out.  If they are already gone
1721         * then urb->use_count must be 0, since disconnected
1722         * devices can't have any active URBs.
1723         */
1724        spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1725        if (atomic_read(&urb->use_count) > 0) {
1726                retval = 0;
1727                usb_get_dev(udev);
1728        }
1729        spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1730        if (retval == 0) {
1731                hcd = bus_to_hcd(urb->dev->bus);
1732                retval = unlink1(hcd, urb, status);
1733                if (retval == 0)
1734                        retval = -EINPROGRESS;
1735                else if (retval != -EIDRM && retval != -EBUSY)
1736                        dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1737                                        urb, retval);
1738                usb_put_dev(udev);
1739        }
1740        return retval;
1741}
1742
1743/*-------------------------------------------------------------------------*/
1744
1745static void __usb_hcd_giveback_urb(struct urb *urb)
1746{
1747        struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1748        struct usb_anchor *anchor = urb->anchor;
1749        int status = urb->unlinked;
1750        unsigned long flags;
1751
1752        urb->hcpriv = NULL;
1753        if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1754            urb->actual_length < urb->transfer_buffer_length &&
1755            !status))
1756                status = -EREMOTEIO;
1757
1758        unmap_urb_for_dma(hcd, urb);
1759        usbmon_urb_complete(&hcd->self, urb, status);
1760        usb_anchor_suspend_wakeups(anchor);
1761        usb_unanchor_urb(urb);
1762        if (likely(status == 0))
1763                usb_led_activity(USB_LED_EVENT_HOST);
1764
1765        /* pass ownership to the completion handler */
1766        urb->status = status;
1767
1768        /*
1769         * We disable local IRQs here avoid possible deadlock because
1770         * drivers may call spin_lock() to hold lock which might be
1771         * acquired in one hard interrupt handler.
1772         *
1773         * The local_irq_save()/local_irq_restore() around complete()
1774         * will be removed if current USB drivers have been cleaned up
1775         * and no one may trigger the above deadlock situation when
1776         * running complete() in tasklet.
1777         */
1778        local_irq_save(flags);
1779        urb->complete(urb);
1780        local_irq_restore(flags);
1781
1782        usb_anchor_resume_wakeups(anchor);
1783        atomic_dec(&urb->use_count);
1784        if (unlikely(atomic_read(&urb->reject)))
1785                wake_up(&usb_kill_urb_queue);
1786        usb_put_urb(urb);
1787}
1788
1789static void usb_giveback_urb_bh(unsigned long param)
1790{
1791        struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1792        struct list_head local_list;
1793
1794        spin_lock_irq(&bh->lock);
1795        bh->running = true;
1796 restart:
1797        list_replace_init(&bh->head, &local_list);
1798        spin_unlock_irq(&bh->lock);
1799
1800        while (!list_empty(&local_list)) {
1801                struct urb *urb;
1802
1803                urb = list_entry(local_list.next, struct urb, urb_list);
1804                list_del_init(&urb->urb_list);
1805                bh->completing_ep = urb->ep;
1806                __usb_hcd_giveback_urb(urb);
1807                bh->completing_ep = NULL;
1808        }
1809
1810        /* check if there are new URBs to giveback */
1811        spin_lock_irq(&bh->lock);
1812        if (!list_empty(&bh->head))
1813                goto restart;
1814        bh->running = false;
1815        spin_unlock_irq(&bh->lock);
1816}
1817
1818/**
1819 * usb_hcd_giveback_urb - return URB from HCD to device driver
1820 * @hcd: host controller returning the URB
1821 * @urb: urb being returned to the USB device driver.
1822 * @status: completion status code for the URB.
1823 * Context: in_interrupt()
1824 *
1825 * This hands the URB from HCD to its USB device driver, using its
1826 * completion function.  The HCD has freed all per-urb resources
1827 * (and is done using urb->hcpriv).  It also released all HCD locks;
1828 * the device driver won't cause problems if it frees, modifies,
1829 * or resubmits this URB.
1830 *
1831 * If @urb was unlinked, the value of @status will be overridden by
1832 * @urb->unlinked.  Erroneous short transfers are detected in case
1833 * the HCD hasn't checked for them.
1834 */
1835void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1836{
1837        struct giveback_urb_bh *bh;
1838        bool running, high_prio_bh;
1839
1840        /* pass status to tasklet via unlinked */
1841        if (likely(!urb->unlinked))
1842                urb->unlinked = status;
1843
1844        if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1845                __usb_hcd_giveback_urb(urb);
1846                return;
1847        }
1848
1849        if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1850                bh = &hcd->high_prio_bh;
1851                high_prio_bh = true;
1852        } else {
1853                bh = &hcd->low_prio_bh;
1854                high_prio_bh = false;
1855        }
1856
1857        spin_lock(&bh->lock);
1858        list_add_tail(&urb->urb_list, &bh->head);
1859        running = bh->running;
1860        spin_unlock(&bh->lock);
1861
1862        if (running)
1863                ;
1864        else if (high_prio_bh)
1865                tasklet_hi_schedule(&bh->bh);
1866        else
1867                tasklet_schedule(&bh->bh);
1868}
1869EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1870
1871/*-------------------------------------------------------------------------*/
1872
1873/* Cancel all URBs pending on this endpoint and wait for the endpoint's
1874 * queue to drain completely.  The caller must first insure that no more
1875 * URBs can be submitted for this endpoint.
1876 */
1877void usb_hcd_flush_endpoint(struct usb_device *udev,
1878                struct usb_host_endpoint *ep)
1879{
1880        struct usb_hcd          *hcd;
1881        struct urb              *urb;
1882
1883        if (!ep)
1884                return;
1885        might_sleep();
1886        hcd = bus_to_hcd(udev->bus);
1887
1888        /* No more submits can occur */
1889        spin_lock_irq(&hcd_urb_list_lock);
1890rescan:
1891        list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1892                int     is_in;
1893
1894                if (urb->unlinked)
1895                        continue;
1896                usb_get_urb (urb);
1897                is_in = usb_urb_dir_in(urb);
1898                spin_unlock(&hcd_urb_list_lock);
1899
1900                /* kick hcd */
1901                unlink1(hcd, urb, -ESHUTDOWN);
1902                dev_dbg (hcd->self.controller,
1903                        "shutdown urb %pK ep%d%s%s\n",
1904                        urb, usb_endpoint_num(&ep->desc),
1905                        is_in ? "in" : "out",
1906                        ({      char *s;
1907
1908                                 switch (usb_endpoint_type(&ep->desc)) {
1909                                 case USB_ENDPOINT_XFER_CONTROL:
1910                                        s = ""; break;
1911                                 case USB_ENDPOINT_XFER_BULK:
1912                                        s = "-bulk"; break;
1913                                 case USB_ENDPOINT_XFER_INT:
1914                                        s = "-intr"; break;
1915                                 default:
1916                                        s = "-iso"; break;
1917                                };
1918                                s;
1919                        }));
1920                usb_put_urb (urb);
1921
1922                /* list contents may have changed */
1923                spin_lock(&hcd_urb_list_lock);
1924                goto rescan;
1925        }
1926        spin_unlock_irq(&hcd_urb_list_lock);
1927
1928        /* Wait until the endpoint queue is completely empty */
1929        while (!list_empty (&ep->urb_list)) {
1930                spin_lock_irq(&hcd_urb_list_lock);
1931
1932                /* The list may have changed while we acquired the spinlock */
1933                urb = NULL;
1934                if (!list_empty (&ep->urb_list)) {
1935                        urb = list_entry (ep->urb_list.prev, struct urb,
1936                                        urb_list);
1937                        usb_get_urb (urb);
1938                }
1939                spin_unlock_irq(&hcd_urb_list_lock);
1940
1941                if (urb) {
1942                        usb_kill_urb (urb);
1943                        usb_put_urb (urb);
1944                }
1945        }
1946}
1947
1948/**
1949 * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1950 *                              the bus bandwidth
1951 * @udev: target &usb_device
1952 * @new_config: new configuration to install
1953 * @cur_alt: the current alternate interface setting
1954 * @new_alt: alternate interface setting that is being installed
1955 *
1956 * To change configurations, pass in the new configuration in new_config,
1957 * and pass NULL for cur_alt and new_alt.
1958 *
1959 * To reset a device's configuration (put the device in the ADDRESSED state),
1960 * pass in NULL for new_config, cur_alt, and new_alt.
1961 *
1962 * To change alternate interface settings, pass in NULL for new_config,
1963 * pass in the current alternate interface setting in cur_alt,
1964 * and pass in the new alternate interface setting in new_alt.
1965 *
1966 * Return: An error if the requested bandwidth change exceeds the
1967 * bus bandwidth or host controller internal resources.
1968 */
1969int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1970                struct usb_host_config *new_config,
1971                struct usb_host_interface *cur_alt,
1972                struct usb_host_interface *new_alt)
1973{
1974        int num_intfs, i, j;
1975        struct usb_host_interface *alt = NULL;
1976        int ret = 0;
1977        struct usb_hcd *hcd;
1978        struct usb_host_endpoint *ep;
1979
1980        hcd = bus_to_hcd(udev->bus);
1981        if (!hcd->driver->check_bandwidth)
1982                return 0;
1983
1984        /* Configuration is being removed - set configuration 0 */
1985        if (!new_config && !cur_alt) {
1986                for (i = 1; i < 16; ++i) {
1987                        ep = udev->ep_out[i];
1988                        if (ep)
1989                                hcd->driver->drop_endpoint(hcd, udev, ep);
1990                        ep = udev->ep_in[i];
1991                        if (ep)
1992                                hcd->driver->drop_endpoint(hcd, udev, ep);
1993                }
1994                hcd->driver->check_bandwidth(hcd, udev);
1995                return 0;
1996        }
1997        /* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1998         * each interface's alt setting 0 and ask the HCD to check the bandwidth
1999         * of the bus.  There will always be bandwidth for endpoint 0, so it's
2000         * ok to exclude it.
2001         */
2002        if (new_config) {
2003                num_intfs = new_config->desc.bNumInterfaces;
2004                /* Remove endpoints (except endpoint 0, which is always on the
2005                 * schedule) from the old config from the schedule
2006                 */
2007                for (i = 1; i < 16; ++i) {
2008                        ep = udev->ep_out[i];
2009                        if (ep) {
2010                                ret = hcd->driver->drop_endpoint(hcd, udev, ep);
2011                                if (ret < 0)
2012                                        goto reset;
2013                        }
2014                        ep = udev->ep_in[i];
2015                        if (ep) {
2016                                ret = hcd->driver->drop_endpoint(hcd, udev, ep);
2017                                if (ret < 0)
2018                                        goto reset;
2019                        }
2020                }
2021                for (i = 0; i < num_intfs; ++i) {
2022                        struct usb_host_interface *first_alt;
2023                        int iface_num;
2024
2025                        first_alt = &new_config->intf_cache[i]->altsetting[0];
2026                        iface_num = first_alt->desc.bInterfaceNumber;
2027                        /* Set up endpoints for alternate interface setting 0 */
2028                        alt = usb_find_alt_setting(new_config, iface_num, 0);
2029                        if (!alt)
2030                                /* No alt setting 0? Pick the first setting. */
2031                                alt = first_alt;
2032
2033                        for (j = 0; j < alt->desc.bNumEndpoints; j++) {
2034                                ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
2035                                if (ret < 0)
2036                                        goto reset;
2037                        }
2038                }
2039        }
2040        if (cur_alt && new_alt) {
2041                struct usb_interface *iface = usb_ifnum_to_if(udev,
2042                                cur_alt->desc.bInterfaceNumber);
2043
2044                if (!iface)
2045                        return -EINVAL;
2046                if (iface->resetting_device) {
2047                        /*
2048                         * The USB core just reset the device, so the xHCI host
2049                         * and the device will think alt setting 0 is installed.
2050                         * However, the USB core will pass in the alternate
2051                         * setting installed before the reset as cur_alt.  Dig
2052                         * out the alternate setting 0 structure, or the first
2053                         * alternate setting if a broken device doesn't have alt
2054                         * setting 0.
2055                         */
2056                        cur_alt = usb_altnum_to_altsetting(iface, 0);
2057                        if (!cur_alt)
2058                                cur_alt = &iface->altsetting[0];
2059                }
2060
2061                /* Drop all the endpoints in the current alt setting */
2062                for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
2063                        ret = hcd->driver->drop_endpoint(hcd, udev,
2064                                        &cur_alt->endpoint[i]);
2065                        if (ret < 0)
2066                                goto reset;
2067                }
2068                /* Add all the endpoints in the new alt setting */
2069                for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
2070                        ret = hcd->driver->add_endpoint(hcd, udev,
2071                                        &new_alt->endpoint[i]);
2072                        if (ret < 0)
2073                                goto reset;
2074                }
2075        }
2076        ret = hcd->driver->check_bandwidth(hcd, udev);
2077reset:
2078        if (ret < 0)
2079                hcd->driver->reset_bandwidth(hcd, udev);
2080        return ret;
2081}
2082
2083/* Disables the endpoint: synchronizes with the hcd to make sure all
2084 * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
2085 * have been called previously.  Use for set_configuration, set_interface,
2086 * driver removal, physical disconnect.
2087 *
2088 * example:  a qh stored in ep->hcpriv, holding state related to endpoint
2089 * type, maxpacket size, toggle, halt status, and scheduling.
2090 */
2091void usb_hcd_disable_endpoint(struct usb_device *udev,
2092                struct usb_host_endpoint *ep)
2093{
2094        struct usb_hcd          *hcd;
2095
2096        might_sleep();
2097        hcd = bus_to_hcd(udev->bus);
2098        if (hcd->driver->endpoint_disable)
2099                hcd->driver->endpoint_disable(hcd, ep);
2100}
2101
2102/**
2103 * usb_hcd_reset_endpoint - reset host endpoint state
2104 * @udev: USB device.
2105 * @ep:   the endpoint to reset.
2106 *
2107 * Resets any host endpoint state such as the toggle bit, sequence
2108 * number and current window.
2109 */
2110void usb_hcd_reset_endpoint(struct usb_device *udev,
2111                            struct usb_host_endpoint *ep)
2112{
2113        struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2114
2115        if (hcd->driver->endpoint_reset)
2116                hcd->driver->endpoint_reset(hcd, ep);
2117        else {
2118                int epnum = usb_endpoint_num(&ep->desc);
2119                int is_out = usb_endpoint_dir_out(&ep->desc);
2120                int is_control = usb_endpoint_xfer_control(&ep->desc);
2121
2122                usb_settoggle(udev, epnum, is_out, 0);
2123                if (is_control)
2124                        usb_settoggle(udev, epnum, !is_out, 0);
2125        }
2126}
2127
2128/**
2129 * usb_alloc_streams - allocate bulk endpoint stream IDs.
2130 * @interface:          alternate setting that includes all endpoints.
2131 * @eps:                array of endpoints that need streams.
2132 * @num_eps:            number of endpoints in the array.
2133 * @num_streams:        number of streams to allocate.
2134 * @mem_flags:          flags hcd should use to allocate memory.
2135 *
2136 * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2137 * Drivers may queue multiple transfers to different stream IDs, which may
2138 * complete in a different order than they were queued.
2139 *
2140 * Return: On success, the number of allocated streams. On failure, a negative
2141 * error code.
2142 */
2143int usb_alloc_streams(struct usb_interface *interface,
2144                struct usb_host_endpoint **eps, unsigned int num_eps,
2145                unsigned int num_streams, gfp_t mem_flags)
2146{
2147        struct usb_hcd *hcd;
2148        struct usb_device *dev;
2149        int i, ret;
2150
2151        dev = interface_to_usbdev(interface);
2152        hcd = bus_to_hcd(dev->bus);
2153        if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2154                return -EINVAL;
2155        if (dev->speed < USB_SPEED_SUPER)
2156                return -EINVAL;
2157        if (dev->state < USB_STATE_CONFIGURED)
2158                return -ENODEV;
2159
2160        for (i = 0; i < num_eps; i++) {
2161                /* Streams only apply to bulk endpoints. */
2162                if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2163                        return -EINVAL;
2164                /* Re-alloc is not allowed */
2165                if (eps[i]->streams)
2166                        return -EINVAL;
2167        }
2168
2169        ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2170                        num_streams, mem_flags);
2171        if (ret < 0)
2172                return ret;
2173
2174        for (i = 0; i < num_eps; i++)
2175                eps[i]->streams = ret;
2176
2177        return ret;
2178}
2179EXPORT_SYMBOL_GPL(usb_alloc_streams);
2180
2181/**
2182 * usb_free_streams - free bulk endpoint stream IDs.
2183 * @interface:  alternate setting that includes all endpoints.
2184 * @eps:        array of endpoints to remove streams from.
2185 * @num_eps:    number of endpoints in the array.
2186 * @mem_flags:  flags hcd should use to allocate memory.
2187 *
2188 * Reverts a group of bulk endpoints back to not using stream IDs.
2189 * Can fail if we are given bad arguments, or HCD is broken.
2190 *
2191 * Return: 0 on success. On failure, a negative error code.
2192 */
2193int usb_free_streams(struct usb_interface *interface,
2194                struct usb_host_endpoint **eps, unsigned int num_eps,
2195                gfp_t mem_flags)
2196{
2197        struct usb_hcd *hcd;
2198        struct usb_device *dev;
2199        int i, ret;
2200
2201        dev = interface_to_usbdev(interface);
2202        hcd = bus_to_hcd(dev->bus);
2203        if (dev->speed < USB_SPEED_SUPER)
2204                return -EINVAL;
2205
2206        /* Double-free is not allowed */
2207        for (i = 0; i < num_eps; i++)
2208                if (!eps[i] || !eps[i]->streams)
2209                        return -EINVAL;
2210
2211        ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2212        if (ret < 0)
2213                return ret;
2214
2215        for (i = 0; i < num_eps; i++)
2216                eps[i]->streams = 0;
2217
2218        return ret;
2219}
2220EXPORT_SYMBOL_GPL(usb_free_streams);
2221
2222/* Protect against drivers that try to unlink URBs after the device
2223 * is gone, by waiting until all unlinks for @udev are finished.
2224 * Since we don't currently track URBs by device, simply wait until
2225 * nothing is running in the locked region of usb_hcd_unlink_urb().
2226 */
2227void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2228{
2229        spin_lock_irq(&hcd_urb_unlink_lock);
2230        spin_unlock_irq(&hcd_urb_unlink_lock);
2231}
2232
2233/*-------------------------------------------------------------------------*/
2234
2235/* called in any context */
2236int usb_hcd_get_frame_number (struct usb_device *udev)
2237{
2238        struct usb_hcd  *hcd = bus_to_hcd(udev->bus);
2239
2240        if (!HCD_RH_RUNNING(hcd))
2241                return -ESHUTDOWN;
2242        return hcd->driver->get_frame_number (hcd);
2243}
2244
2245/*-------------------------------------------------------------------------*/
2246
2247#ifdef  CONFIG_PM
2248
2249int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2250{
2251        struct usb_hcd  *hcd = bus_to_hcd(rhdev->bus);
2252        int             status;
2253        int             old_state = hcd->state;
2254
2255        dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2256                        (PMSG_IS_AUTO(msg) ? "auto-" : ""),
2257                        rhdev->do_remote_wakeup);
2258        if (HCD_DEAD(hcd)) {
2259                dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2260                return 0;
2261        }
2262
2263        if (!hcd->driver->bus_suspend) {
2264                status = -ENOENT;
2265        } else {
2266                clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2267                hcd->state = HC_STATE_QUIESCING;
2268                status = hcd->driver->bus_suspend(hcd);
2269        }
2270        if (status == 0) {
2271                usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2272                hcd->state = HC_STATE_SUSPENDED;
2273
2274                /* Did we race with a root-hub wakeup event? */
2275                if (rhdev->do_remote_wakeup) {
2276                        char    buffer[6];
2277
2278                        status = hcd->driver->hub_status_data(hcd, buffer);
2279                        if (status != 0) {
2280                                dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2281                                hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2282                                status = -EBUSY;
2283                        }
2284                }
2285        } else {
2286                spin_lock_irq(&hcd_root_hub_lock);
2287                if (!HCD_DEAD(hcd)) {
2288                        set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2289                        hcd->state = old_state;
2290                }
2291                spin_unlock_irq(&hcd_root_hub_lock);
2292                dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2293                                "suspend", status);
2294        }
2295        return status;
2296}
2297
2298int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2299{
2300        struct usb_hcd  *hcd = bus_to_hcd(rhdev->bus);
2301        int             status;
2302        int             old_state = hcd->state;
2303
2304        dev_dbg(&rhdev->dev, "usb %sresume\n",
2305                        (PMSG_IS_AUTO(msg) ? "auto-" : ""));
2306        if (HCD_DEAD(hcd)) {
2307                dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2308                return 0;
2309        }
2310        if (!hcd->driver->bus_resume)
2311                return -ENOENT;
2312        if (HCD_RH_RUNNING(hcd))
2313                return 0;
2314
2315        hcd->state = HC_STATE_RESUMING;
2316        status = hcd->driver->bus_resume(hcd);
2317        clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2318        if (status == 0) {
2319                struct usb_device *udev;
2320                int port1;
2321
2322                spin_lock_irq(&hcd_root_hub_lock);
2323                if (!HCD_DEAD(hcd)) {
2324                        usb_set_device_state(rhdev, rhdev->actconfig
2325                                        ? USB_STATE_CONFIGURED
2326                                        : USB_STATE_ADDRESS);
2327                        set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2328                        hcd->state = HC_STATE_RUNNING;
2329                }
2330                spin_unlock_irq(&hcd_root_hub_lock);
2331
2332                /*
2333                 * Check whether any of the enabled ports on the root hub are
2334                 * unsuspended.  If they are then a TRSMRCY delay is needed
2335                 * (this is what the USB-2 spec calls a "global resume").
2336                 * Otherwise we can skip the delay.
2337                 */
2338                usb_hub_for_each_child(rhdev, port1, udev) {
2339                        if (udev->state != USB_STATE_NOTATTACHED &&
2340                                        !udev->port_is_suspended) {
2341                                usleep_range(10000, 11000);     /* TRSMRCY */
2342                                break;
2343                        }
2344                }
2345        } else {
2346                hcd->state = old_state;
2347                dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2348                                "resume", status);
2349                if (status != -ESHUTDOWN)
2350                        usb_hc_died(hcd);
2351        }
2352        return status;
2353}
2354
2355/* Workqueue routine for root-hub remote wakeup */
2356static void hcd_resume_work(struct work_struct *work)
2357{
2358        struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2359        struct usb_device *udev = hcd->self.root_hub;
2360
2361        usb_remote_wakeup(udev);
2362}
2363
2364/**
2365 * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2366 * @hcd: host controller for this root hub
2367 *
2368 * The USB host controller calls this function when its root hub is
2369 * suspended (with the remote wakeup feature enabled) and a remote
2370 * wakeup request is received.  The routine submits a workqueue request
2371 * to resume the root hub (that is, manage its downstream ports again).
2372 */
2373void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2374{
2375        unsigned long flags;
2376
2377        spin_lock_irqsave (&hcd_root_hub_lock, flags);
2378        if (hcd->rh_registered) {
2379                set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2380                queue_work(pm_wq, &hcd->wakeup_work);
2381        }
2382        spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2383}
2384EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2385
2386#endif  /* CONFIG_PM */
2387
2388/*-------------------------------------------------------------------------*/
2389
2390#ifdef  CONFIG_USB_OTG
2391
2392/**
2393 * usb_bus_start_enum - start immediate enumeration (for OTG)
2394 * @bus: the bus (must use hcd framework)
2395 * @port_num: 1-based number of port; usually bus->otg_port
2396 * Context: in_interrupt()
2397 *
2398 * Starts enumeration, with an immediate reset followed later by
2399 * hub_wq identifying and possibly configuring the device.
2400 * This is needed by OTG controller drivers, where it helps meet
2401 * HNP protocol timing requirements for starting a port reset.
2402 *
2403 * Return: 0 if successful.
2404 */
2405int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2406{
2407        struct usb_hcd          *hcd;
2408        int                     status = -EOPNOTSUPP;
2409
2410        /* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2411         * boards with root hubs hooked up to internal devices (instead of
2412         * just the OTG port) may need more attention to resetting...
2413         */
2414        hcd = bus_to_hcd(bus);
2415        if (port_num && hcd->driver->start_port_reset)
2416                status = hcd->driver->start_port_reset(hcd, port_num);
2417
2418        /* allocate hub_wq shortly after (first) root port reset finishes;
2419         * it may issue others, until at least 50 msecs have passed.
2420         */
2421        if (status == 0)
2422                mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2423        return status;
2424}
2425EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2426
2427#endif
2428
2429/*-------------------------------------------------------------------------*/
2430
2431/**
2432 * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2433 * @irq: the IRQ being raised
2434 * @__hcd: pointer to the HCD whose IRQ is being signaled
2435 *
2436 * If the controller isn't HALTed, calls the driver's irq handler.
2437 * Checks whether the controller is now dead.
2438 *
2439 * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2440 */
2441irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2442{
2443        struct usb_hcd          *hcd = __hcd;
2444        irqreturn_t             rc;
2445
2446        if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2447                rc = IRQ_NONE;
2448        else if (hcd->driver->irq(hcd) == IRQ_NONE)
2449                rc = IRQ_NONE;
2450        else
2451                rc = IRQ_HANDLED;
2452
2453        return rc;
2454}
2455EXPORT_SYMBOL_GPL(usb_hcd_irq);
2456
2457/*-------------------------------------------------------------------------*/
2458
2459/**
2460 * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2461 * @hcd: pointer to the HCD representing the controller
2462 *
2463 * This is called by bus glue to report a USB host controller that died
2464 * while operations may still have been pending.  It's called automatically
2465 * by the PCI glue, so only glue for non-PCI busses should need to call it.
2466 *
2467 * Only call this function with the primary HCD.
2468 */
2469void usb_hc_died (struct usb_hcd *hcd)
2470{
2471        unsigned long flags;
2472
2473        dev_err (hcd->self.controller, "HC died; cleaning up\n");
2474
2475        spin_lock_irqsave (&hcd_root_hub_lock, flags);
2476        clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2477        set_bit(HCD_FLAG_DEAD, &hcd->flags);
2478        if (hcd->rh_registered) {
2479                clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2480
2481                /* make hub_wq clean up old urbs and devices */
2482                usb_set_device_state (hcd->self.root_hub,
2483                                USB_STATE_NOTATTACHED);
2484                usb_kick_hub_wq(hcd->self.root_hub);
2485        }
2486        if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2487                hcd = hcd->shared_hcd;
2488                clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2489                set_bit(HCD_FLAG_DEAD, &hcd->flags);
2490                if (hcd->rh_registered) {
2491                        clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2492
2493                        /* make hub_wq clean up old urbs and devices */
2494                        usb_set_device_state(hcd->self.root_hub,
2495                                        USB_STATE_NOTATTACHED);
2496                        usb_kick_hub_wq(hcd->self.root_hub);
2497                }
2498        }
2499        spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2500        /* Make sure that the other roothub is also deallocated. */
2501}
2502EXPORT_SYMBOL_GPL (usb_hc_died);
2503
2504/*-------------------------------------------------------------------------*/
2505
2506static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2507{
2508
2509        spin_lock_init(&bh->lock);
2510        INIT_LIST_HEAD(&bh->head);
2511        tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2512}
2513
2514struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2515                struct device *sysdev, struct device *dev, const char *bus_name,
2516                struct usb_hcd *primary_hcd)
2517{
2518        struct usb_hcd *hcd;
2519
2520        hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2521        if (!hcd)
2522                return NULL;
2523        if (primary_hcd == NULL) {
2524                hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2525                                GFP_KERNEL);
2526                if (!hcd->address0_mutex) {
2527                        kfree(hcd);
2528                        dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2529                        return NULL;
2530                }
2531                mutex_init(hcd->address0_mutex);
2532                hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2533                                GFP_KERNEL);
2534                if (!hcd->bandwidth_mutex) {
2535                        kfree(hcd->address0_mutex);
2536                        kfree(hcd);
2537                        dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2538                        return NULL;
2539                }
2540                mutex_init(hcd->bandwidth_mutex);
2541                dev_set_drvdata(dev, hcd);
2542        } else {
2543                mutex_lock(&usb_port_peer_mutex);
2544                hcd->address0_mutex = primary_hcd->address0_mutex;
2545                hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2546                hcd->primary_hcd = primary_hcd;
2547                primary_hcd->primary_hcd = primary_hcd;
2548                hcd->shared_hcd = primary_hcd;
2549                primary_hcd->shared_hcd = hcd;
2550                mutex_unlock(&usb_port_peer_mutex);
2551        }
2552
2553        kref_init(&hcd->kref);
2554
2555        usb_bus_init(&hcd->self);
2556        hcd->self.controller = dev;
2557        hcd->self.sysdev = sysdev;
2558        hcd->self.bus_name = bus_name;
2559        hcd->self.uses_dma = (sysdev->dma_mask != NULL);
2560
2561        init_timer(&hcd->rh_timer);
2562        hcd->rh_timer.function = rh_timer_func;
2563        hcd->rh_timer.data = (unsigned long) hcd;
2564#ifdef CONFIG_PM
2565        INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2566#endif
2567
2568        hcd->driver = driver;
2569        hcd->speed = driver->flags & HCD_MASK;
2570        hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2571                        "USB Host Controller";
2572        return hcd;
2573}
2574EXPORT_SYMBOL_GPL(__usb_create_hcd);
2575
2576/**
2577 * usb_create_shared_hcd - create and initialize an HCD structure
2578 * @driver: HC driver that will use this hcd
2579 * @dev: device for this HC, stored in hcd->self.controller
2580 * @bus_name: value to store in hcd->self.bus_name
2581 * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2582 *              PCI device.  Only allocate certain resources for the primary HCD
2583 * Context: !in_interrupt()
2584 *
2585 * Allocate a struct usb_hcd, with extra space at the end for the
2586 * HC driver's private data.  Initialize the generic members of the
2587 * hcd structure.
2588 *
2589 * Return: On success, a pointer to the created and initialized HCD structure.
2590 * On failure (e.g. if memory is unavailable), %NULL.
2591 */
2592struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2593                struct device *dev, const char *bus_name,
2594                struct usb_hcd *primary_hcd)
2595{
2596        return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2597}
2598EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2599
2600/**
2601 * usb_create_hcd - create and initialize an HCD structure
2602 * @driver: HC driver that will use this hcd
2603 * @dev: device for this HC, stored in hcd->self.controller
2604 * @bus_name: value to store in hcd->self.bus_name
2605 * Context: !in_interrupt()
2606 *
2607 * Allocate a struct usb_hcd, with extra space at the end for the
2608 * HC driver's private data.  Initialize the generic members of the
2609 * hcd structure.
2610 *
2611 * Return: On success, a pointer to the created and initialized HCD
2612 * structure. On failure (e.g. if memory is unavailable), %NULL.
2613 */
2614struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2615                struct device *dev, const char *bus_name)
2616{
2617        return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2618}
2619EXPORT_SYMBOL_GPL(usb_create_hcd);
2620
2621/*
2622 * Roothubs that share one PCI device must also share the bandwidth mutex.
2623 * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2624 * deallocated.
2625 *
2626 * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2627 * freed.  When hcd_release() is called for either hcd in a peer set,
2628 * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2629 */
2630static void hcd_release(struct kref *kref)
2631{
2632        struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2633
2634        mutex_lock(&usb_port_peer_mutex);
2635        if (hcd->shared_hcd) {
2636                struct usb_hcd *peer = hcd->shared_hcd;
2637
2638                peer->shared_hcd = NULL;
2639                peer->primary_hcd = NULL;
2640        } else {
2641                kfree(hcd->address0_mutex);
2642                kfree(hcd->bandwidth_mutex);
2643        }
2644        mutex_unlock(&usb_port_peer_mutex);
2645        kfree(hcd);
2646}
2647
2648struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2649{
2650        if (hcd)
2651                kref_get (&hcd->kref);
2652        return hcd;
2653}
2654EXPORT_SYMBOL_GPL(usb_get_hcd);
2655
2656void usb_put_hcd (struct usb_hcd *hcd)
2657{
2658        if (hcd)
2659                kref_put (&hcd->kref, hcd_release);
2660}
2661EXPORT_SYMBOL_GPL(usb_put_hcd);
2662
2663int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2664{
2665        if (!hcd->primary_hcd)
2666                return 1;
2667        return hcd == hcd->primary_hcd;
2668}
2669EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2670
2671int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2672{
2673        if (!hcd->driver->find_raw_port_number)
2674                return port1;
2675
2676        return hcd->driver->find_raw_port_number(hcd, port1);
2677}
2678
2679static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2680                unsigned int irqnum, unsigned long irqflags)
2681{
2682        int retval;
2683
2684        if (hcd->driver->irq) {
2685
2686                snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2687                                hcd->driver->description, hcd->self.busnum);
2688                retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2689                                hcd->irq_descr, hcd);
2690                if (retval != 0) {
2691                        dev_err(hcd->self.controller,
2692                                        "request interrupt %d failed\n",
2693                                        irqnum);
2694                        return retval;
2695                }
2696                hcd->irq = irqnum;
2697                dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2698                                (hcd->driver->flags & HCD_MEMORY) ?
2699                                        "io mem" : "io base",
2700                                        (unsigned long long)hcd->rsrc_start);
2701        } else {
2702                hcd->irq = 0;
2703                if (hcd->rsrc_start)
2704                        dev_info(hcd->self.controller, "%s 0x%08llx\n",
2705                                        (hcd->driver->flags & HCD_MEMORY) ?
2706                                        "io mem" : "io base",
2707                                        (unsigned long long)hcd->rsrc_start);
2708        }
2709        return 0;
2710}
2711
2712/*
2713 * Before we free this root hub, flush in-flight peering attempts
2714 * and disable peer lookups
2715 */
2716static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2717{
2718        struct usb_device *rhdev;
2719
2720        mutex_lock(&usb_port_peer_mutex);
2721        rhdev = hcd->self.root_hub;
2722        hcd->self.root_hub = NULL;
2723        mutex_unlock(&usb_port_peer_mutex);
2724        usb_put_dev(rhdev);
2725}
2726
2727/**
2728 * usb_add_hcd - finish generic HCD structure initialization and register
2729 * @hcd: the usb_hcd structure to initialize
2730 * @irqnum: Interrupt line to allocate
2731 * @irqflags: Interrupt type flags
2732 *
2733 * Finish the remaining parts of generic HCD initialization: allocate the
2734 * buffers of consistent memory, register the bus, request the IRQ line,
2735 * and call the driver's reset() and start() routines.
2736 */
2737int usb_add_hcd(struct usb_hcd *hcd,
2738                unsigned int irqnum, unsigned long irqflags)
2739{
2740        int retval;
2741        struct usb_device *rhdev;
2742
2743        if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->usb_phy) {
2744                struct usb_phy *phy = usb_get_phy_dev(hcd->self.sysdev, 0);
2745
2746                if (IS_ERR(phy)) {
2747                        retval = PTR_ERR(phy);
2748                        if (retval == -EPROBE_DEFER)
2749                                return retval;
2750                } else {
2751                        retval = usb_phy_init(phy);
2752                        if (retval) {
2753                                usb_put_phy(phy);
2754                                return retval;
2755                        }
2756                        hcd->usb_phy = phy;
2757                        hcd->remove_phy = 1;
2758                }
2759        }
2760
2761        if (IS_ENABLED(CONFIG_GENERIC_PHY) && !hcd->phy) {
2762                struct phy *phy = phy_get(hcd->self.sysdev, "usb");
2763
2764                if (IS_ERR(phy)) {
2765                        retval = PTR_ERR(phy);
2766                        if (retval == -EPROBE_DEFER)
2767                                goto err_phy;
2768                } else {
2769                        retval = phy_init(phy);
2770                        if (retval) {
2771                                phy_put(phy);
2772                                goto err_phy;
2773                        }
2774                        retval = phy_power_on(phy);
2775                        if (retval) {
2776                                phy_exit(phy);
2777                                phy_put(phy);
2778                                goto err_phy;
2779                        }
2780                        hcd->phy = phy;
2781                        hcd->remove_phy = 1;
2782                }
2783        }
2784
2785        dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2786
2787        /* Keep old behaviour if authorized_default is not in [0, 1]. */
2788        if (authorized_default < 0 || authorized_default > 1) {
2789                if (hcd->wireless)
2790                        clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2791                else
2792                        set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2793        } else {
2794                if (authorized_default)
2795                        set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2796                else
2797                        clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2798        }
2799        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2800
2801        /* per default all interfaces are authorized */
2802        set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2803
2804        /* HC is in reset state, but accessible.  Now do the one-time init,
2805         * bottom up so that hcds can customize the root hubs before hub_wq
2806         * starts talking to them.  (Note, bus id is assigned early too.)
2807         */
2808        retval = hcd_buffer_create(hcd);
2809        if (retval != 0) {
2810                dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2811                goto err_create_buf;
2812        }
2813
2814        retval = usb_register_bus(&hcd->self);
2815        if (retval < 0)
2816                goto err_register_bus;
2817
2818        rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2819        if (rhdev == NULL) {
2820                dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2821                retval = -ENOMEM;
2822                goto err_allocate_root_hub;
2823        }
2824        mutex_lock(&usb_port_peer_mutex);
2825        hcd->self.root_hub = rhdev;
2826        mutex_unlock(&usb_port_peer_mutex);
2827
2828        switch (hcd->speed) {
2829        case HCD_USB11:
2830                rhdev->speed = USB_SPEED_FULL;
2831                break;
2832        case HCD_USB2:
2833                rhdev->speed = USB_SPEED_HIGH;
2834                break;
2835        case HCD_USB25:
2836                rhdev->speed = USB_SPEED_WIRELESS;
2837                break;
2838        case HCD_USB3:
2839                rhdev->speed = USB_SPEED_SUPER;
2840                break;
2841        case HCD_USB31:
2842                rhdev->speed = USB_SPEED_SUPER_PLUS;
2843                break;
2844        default:
2845                retval = -EINVAL;
2846                goto err_set_rh_speed;
2847        }
2848
2849        /* wakeup flag init defaults to "everything works" for root hubs,
2850         * but drivers can override it in reset() if needed, along with
2851         * recording the overall controller's system wakeup capability.
2852         */
2853        device_set_wakeup_capable(&rhdev->dev, 1);
2854
2855        /* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2856         * registered.  But since the controller can die at any time,
2857         * let's initialize the flag before touching the hardware.
2858         */
2859        set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2860
2861        /* "reset" is misnamed; its role is now one-time init. the controller
2862         * should already have been reset (and boot firmware kicked off etc).
2863         */
2864        if (hcd->driver->reset) {
2865                retval = hcd->driver->reset(hcd);
2866                if (retval < 0) {
2867                        dev_err(hcd->self.controller, "can't setup: %d\n",
2868                                        retval);
2869                        goto err_hcd_driver_setup;
2870                }
2871        }
2872        hcd->rh_pollable = 1;
2873
2874        /* NOTE: root hub and controller capabilities may not be the same */
2875        if (device_can_wakeup(hcd->self.controller)
2876                        && device_can_wakeup(&hcd->self.root_hub->dev))
2877                dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2878
2879        /* initialize tasklets */
2880        init_giveback_urb_bh(&hcd->high_prio_bh);
2881        init_giveback_urb_bh(&hcd->low_prio_bh);
2882
2883        /* enable irqs just before we start the controller,
2884         * if the BIOS provides legacy PCI irqs.
2885         */
2886        if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2887                retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2888                if (retval)
2889                        goto err_request_irq;
2890        }
2891
2892        hcd->state = HC_STATE_RUNNING;
2893        retval = hcd->driver->start(hcd);
2894        if (retval < 0) {
2895                dev_err(hcd->self.controller, "startup error %d\n", retval);
2896                goto err_hcd_driver_start;
2897        }
2898
2899        /* starting here, usbcore will pay attention to this root hub */
2900        retval = register_root_hub(hcd);
2901        if (retval != 0)
2902                goto err_register_root_hub;
2903
2904        retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2905        if (retval < 0) {
2906                printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2907                       retval);
2908                goto error_create_attr_group;
2909        }
2910        if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2911                usb_hcd_poll_rh_status(hcd);
2912
2913        return retval;
2914
2915error_create_attr_group:
2916        clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2917        if (HC_IS_RUNNING(hcd->state))
2918                hcd->state = HC_STATE_QUIESCING;
2919        spin_lock_irq(&hcd_root_hub_lock);
2920        hcd->rh_registered = 0;
2921        spin_unlock_irq(&hcd_root_hub_lock);
2922
2923#ifdef CONFIG_PM
2924        cancel_work_sync(&hcd->wakeup_work);
2925#endif
2926        mutex_lock(&usb_bus_idr_lock);
2927        usb_disconnect(&rhdev);         /* Sets rhdev to NULL */
2928        mutex_unlock(&usb_bus_idr_lock);
2929err_register_root_hub:
2930        hcd->rh_pollable = 0;
2931        clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2932        del_timer_sync(&hcd->rh_timer);
2933        hcd->driver->stop(hcd);
2934        hcd->state = HC_STATE_HALT;
2935        clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2936        del_timer_sync(&hcd->rh_timer);
2937err_hcd_driver_start:
2938        if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2939                free_irq(irqnum, hcd);
2940err_request_irq:
2941err_hcd_driver_setup:
2942err_set_rh_speed:
2943        usb_put_invalidate_rhdev(hcd);
2944err_allocate_root_hub:
2945        usb_deregister_bus(&hcd->self);
2946err_register_bus:
2947        hcd_buffer_destroy(hcd);
2948err_create_buf:
2949        if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) {
2950                phy_power_off(hcd->phy);
2951                phy_exit(hcd->phy);
2952                phy_put(hcd->phy);
2953                hcd->phy = NULL;
2954        }
2955err_phy:
2956        if (hcd->remove_phy && hcd->usb_phy) {
2957                usb_phy_shutdown(hcd->usb_phy);
2958                usb_put_phy(hcd->usb_phy);
2959                hcd->usb_phy = NULL;
2960        }
2961        return retval;
2962}
2963EXPORT_SYMBOL_GPL(usb_add_hcd);
2964
2965/**
2966 * usb_remove_hcd - shutdown processing for generic HCDs
2967 * @hcd: the usb_hcd structure to remove
2968 * Context: !in_interrupt()
2969 *
2970 * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2971 * invoking the HCD's stop() method.
2972 */
2973void usb_remove_hcd(struct usb_hcd *hcd)
2974{
2975        struct usb_device *rhdev = hcd->self.root_hub;
2976
2977        dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2978
2979        usb_get_dev(rhdev);
2980        sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2981
2982        clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2983        if (HC_IS_RUNNING (hcd->state))
2984                hcd->state = HC_STATE_QUIESCING;
2985
2986        dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2987        spin_lock_irq (&hcd_root_hub_lock);
2988        hcd->rh_registered = 0;
2989        spin_unlock_irq (&hcd_root_hub_lock);
2990
2991#ifdef CONFIG_PM
2992        cancel_work_sync(&hcd->wakeup_work);
2993#endif
2994
2995        mutex_lock(&usb_bus_idr_lock);
2996        usb_disconnect(&rhdev);         /* Sets rhdev to NULL */
2997        mutex_unlock(&usb_bus_idr_lock);
2998
2999        /*
3000         * tasklet_kill() isn't needed here because:
3001         * - driver's disconnect() called from usb_disconnect() should
3002         *   make sure its URBs are completed during the disconnect()
3003         *   callback
3004         *
3005         * - it is too late to run complete() here since driver may have
3006         *   been removed already now
3007         */
3008
3009        /* Prevent any more root-hub status calls from the timer.
3010         * The HCD might still restart the timer (if a port status change
3011         * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
3012         * the hub_status_data() callback.
3013         */
3014        hcd->rh_pollable = 0;
3015        clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3016        del_timer_sync(&hcd->rh_timer);
3017
3018        hcd->driver->stop(hcd);
3019        hcd->state = HC_STATE_HALT;
3020
3021        /* In case the HCD restarted the timer, stop it again. */
3022        clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3023        del_timer_sync(&hcd->rh_timer);
3024
3025        if (usb_hcd_is_primary_hcd(hcd)) {
3026                if (hcd->irq > 0)
3027                        free_irq(hcd->irq, hcd);
3028        }
3029
3030        usb_deregister_bus(&hcd->self);
3031        hcd_buffer_destroy(hcd);
3032
3033        if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) {
3034                phy_power_off(hcd->phy);
3035                phy_exit(hcd->phy);
3036                phy_put(hcd->phy);
3037                hcd->phy = NULL;
3038        }
3039        if (hcd->remove_phy && hcd->usb_phy) {
3040                usb_phy_shutdown(hcd->usb_phy);
3041                usb_put_phy(hcd->usb_phy);
3042                hcd->usb_phy = NULL;
3043        }
3044
3045        usb_put_invalidate_rhdev(hcd);
3046        hcd->flags = 0;
3047}
3048EXPORT_SYMBOL_GPL(usb_remove_hcd);
3049
3050void
3051usb_hcd_platform_shutdown(struct platform_device *dev)
3052{
3053        struct usb_hcd *hcd = platform_get_drvdata(dev);
3054
3055        if (hcd->driver->shutdown)
3056                hcd->driver->shutdown(hcd);
3057}
3058EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3059
3060/*-------------------------------------------------------------------------*/
3061
3062#if IS_ENABLED(CONFIG_USB_MON)
3063
3064const struct usb_mon_operations *mon_ops;
3065
3066/*
3067 * The registration is unlocked.
3068 * We do it this way because we do not want to lock in hot paths.
3069 *
3070 * Notice that the code is minimally error-proof. Because usbmon needs
3071 * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3072 */
3073
3074int usb_mon_register(const struct usb_mon_operations *ops)
3075{
3076
3077        if (mon_ops)
3078                return -EBUSY;
3079
3080        mon_ops = ops;
3081        mb();
3082        return 0;
3083}
3084EXPORT_SYMBOL_GPL (usb_mon_register);
3085
3086void usb_mon_deregister (void)
3087{
3088
3089        if (mon_ops == NULL) {
3090                printk(KERN_ERR "USB: monitor was not registered\n");
3091                return;
3092        }
3093        mon_ops = NULL;
3094        mb();
3095}
3096EXPORT_SYMBOL_GPL (usb_mon_deregister);
3097
3098#endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
3099