drivers/usb/core/hcd.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * (C) Copyright Linus Torvalds 1999
   4  * (C) Copyright Johannes Erdfelt 1999-2001
   5  * (C) Copyright Andreas Gal 1999
   6  * (C) Copyright Gregory P. Smith 1999
   7  * (C) Copyright Deti Fliegl 1999
   8  * (C) Copyright Randy Dunlap 2000
   9  * (C) Copyright David Brownell 2000-2002
  10  */
  11
  12 #include <linux/bcd.h>
  13 #include <linux/module.h>
  14 #include <linux/version.h>
  15 #include <linux/kernel.h>
  16 #include <linux/sched/task_stack.h>
  17 #include <linux/slab.h>
  18 #include <linux/completion.h>
  19 #include <linux/utsname.h>
  20 #include <linux/mm.h>
  21 #include <asm/io.h>
  22 #include <linux/device.h>
  23 #include <linux/dma-mapping.h>
  24 #include <linux/mutex.h>
  25 #include <asm/irq.h>
  26 #include <asm/byteorder.h>
  27 #include <asm/unaligned.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/workqueue.h>
  30 #include <linux/pm_runtime.h>
  31 #include <linux/types.h>
  32
  33 #include <linux/phy/phy.h>
  34 #include <linux/usb.h>
  35 #include <linux/usb/hcd.h>
  36 #include <linux/usb/otg.h>
  37
  38 #include "usb.h"
  39 #include "phy.h"
  40
  41
  42 /*-------------------------------------------------------------------------*/
  43
  44 /*
  45  * USB Host Controller Driver framework
  46  *
  47  * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
  48  * HCD-specific behaviors/bugs.
  49  *
  50  * This does error checks, tracks devices and urbs, and delegates to a
  51  * "hc_driver" only for code (and data) that really needs to know about
  52  * hardware differences.  That includes root hub registers, i/o queues,
  53  * and so on ... but as little else as possible.
  54  *
  55  * Shared code includes most of the "root hub" code (these are emulated,
  56  * though each HC's hardware works differently) and PCI glue, plus request
  57  * tracking overhead.  The HCD code should only block on spinlocks or on
  58  * hardware handshaking; blocking on software events (such as other kernel
  59  * threads releasing resources, or completing actions) is all generic.
  60  *
  61  * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
  62  * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
  63  * only by the hub driver ... and that neither should be seen or used by
  64  * usb client device drivers.
  65  *
  66  * Contributors of ideas or unattributed patches include: David Brownell,
  67  * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
  68  *
  69  * HISTORY:
  70  * 2002-02-21   Pull in most of the usb_bus support from usb.c; some
  71  *              associated cleanup.  "usb_hcd" still != "usb_bus".
  72  * 2001-12-12   Initial patch version for Linux 2.5.1 kernel.
  73  */
  74
  75 /*-------------------------------------------------------------------------*/
  76
  77 /* Keep track of which host controller drivers are loaded */
  78 unsigned long usb_hcds_loaded;
  79 EXPORT_SYMBOL_GPL(usb_hcds_loaded);
  80
  81 /* host controllers we manage */
  82 DEFINE_IDR (usb_bus_idr);
  83 EXPORT_SYMBOL_GPL (usb_bus_idr);
  84
  85 /* used when allocating bus numbers */
  86 #define USB_MAXBUS              64
  87
  88 /* used when updating list of hcds */
  89 DEFINE_MUTEX(usb_bus_idr_lock); /* exported only for usbfs */
  90 EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
  91
  92 /* used for controlling access to virtual root hubs */
  93 static DEFINE_SPINLOCK(hcd_root_hub_lock);
  94
  95 /* used when updating an endpoint's URB list */
  96 static DEFINE_SPINLOCK(hcd_urb_list_lock);
  97
  98 /* used to protect against unlinking URBs after the device is gone */
  99 static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
 100
 101 /* wait queue for synchronous unlinks */
 102 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
 103
 104 static inline int is_root_hub(struct usb_device *udev)
 105 {
 106         return (udev->parent == NULL);
 107 }
 108
 109 /*-------------------------------------------------------------------------*/
 110
 111 /*
 112  * Sharable chunks of root hub code.
 113  */
 114
 115 /*-------------------------------------------------------------------------*/
 116 #define KERNEL_REL      bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
 117 #define KERNEL_VER      bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
 118
 119 /* usb 3.1 root hub device descriptor */
 120 static const u8 usb31_rh_dev_descriptor[18] = {
 121         0x12,       /*  __u8  bLength; */
 122         USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 123         0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
 124
 125         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 126         0x00,       /*  __u8  bDeviceSubClass; */
 127         0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
 128         0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
 129
 130         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 131         0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
 132         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 133
 134         0x03,       /*  __u8  iManufacturer; */
 135         0x02,       /*  __u8  iProduct; */
 136         0x01,       /*  __u8  iSerialNumber; */
 137         0x01        /*  __u8  bNumConfigurations; */
 138 };
 139
 140 /* usb 3.0 root hub device descriptor */
 141 static const u8 usb3_rh_dev_descriptor[18] = {
 142         0x12,       /*  __u8  bLength; */
 143         USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 144         0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
 145
 146         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 147         0x00,       /*  __u8  bDeviceSubClass; */
 148         0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
 149         0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
 150
 151         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 152         0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
 153         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 154
 155         0x03,       /*  __u8  iManufacturer; */
 156         0x02,       /*  __u8  iProduct; */
 157         0x01,       /*  __u8  iSerialNumber; */
 158         0x01        /*  __u8  bNumConfigurations; */
 159 };
 160
 161 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */
 162 static const u8 usb25_rh_dev_descriptor[18] = {
 163         0x12,       /*  __u8  bLength; */
 164         USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 165         0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
 166
 167         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 168         0x00,       /*  __u8  bDeviceSubClass; */
 169         0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 170         0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
 171
 172         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 173         0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 174         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 175
 176         0x03,       /*  __u8  iManufacturer; */
 177         0x02,       /*  __u8  iProduct; */
 178         0x01,       /*  __u8  iSerialNumber; */
 179         0x01        /*  __u8  bNumConfigurations; */
 180 };
 181
 182 /* usb 2.0 root hub device descriptor */
 183 static const u8 usb2_rh_dev_descriptor[18] = {
 184         0x12,       /*  __u8  bLength; */
 185         USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 186         0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
 187
 188         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 189         0x00,       /*  __u8  bDeviceSubClass; */
 190         0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 191         0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 192
 193         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 194         0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 195         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 196
 197         0x03,       /*  __u8  iManufacturer; */
 198         0x02,       /*  __u8  iProduct; */
 199         0x01,       /*  __u8  iSerialNumber; */
 200         0x01        /*  __u8  bNumConfigurations; */
 201 };
 202
 203 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
 204
 205 /* usb 1.1 root hub device descriptor */
 206 static const u8 usb11_rh_dev_descriptor[18] = {
 207         0x12,       /*  __u8  bLength; */
 208         USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 209         0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
 210
 211         0x09,       /*  __u8  bDeviceClass; HUB_CLASSCODE */
 212         0x00,       /*  __u8  bDeviceSubClass; */
 213         0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
 214         0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 215
 216         0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 217         0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
 218         KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 219
 220         0x03,       /*  __u8  iManufacturer; */
 221         0x02,       /*  __u8  iProduct; */
 222         0x01,       /*  __u8  iSerialNumber; */
 223         0x01        /*  __u8  bNumConfigurations; */
 224 };
 225
 226
 227 /*-------------------------------------------------------------------------*/
 228
 229 /* Configuration descriptors for our root hubs */
 230
 231 static const u8 fs_rh_config_descriptor[] = {
 232
 233         /* one configuration */
 234         0x09,       /*  __u8  bLength; */
 235         USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 236         0x19, 0x00, /*  __le16 wTotalLength; */
 237         0x01,       /*  __u8  bNumInterfaces; (1) */
 238         0x01,       /*  __u8  bConfigurationValue; */
 239         0x00,       /*  __u8  iConfiguration; */
 240         0xc0,       /*  __u8  bmAttributes;
 241                                  Bit 7: must be set,
 242                                      6: Self-powered,
 243                                      5: Remote wakeup,
 244                                      4..0: resvd */
 245         0x00,       /*  __u8  MaxPower; */
 246
 247         /* USB 1.1:
 248          * USB 2.0, single TT organization (mandatory):
 249          *      one interface, protocol 0
 250          *
 251          * USB 2.0, multiple TT organization (optional):
 252          *      two interfaces, protocols 1 (like single TT)
 253          *      and 2 (multiple TT mode) ... config is
 254          *      sometimes settable
 255          *      NOT IMPLEMENTED
 256          */
 257
 258         /* one interface */
 259         0x09,       /*  __u8  if_bLength; */
 260         USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
 261         0x00,       /*  __u8  if_bInterfaceNumber; */
 262         0x00,       /*  __u8  if_bAlternateSetting; */
 263         0x01,       /*  __u8  if_bNumEndpoints; */
 264         0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 265         0x00,       /*  __u8  if_bInterfaceSubClass; */
 266         0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 267         0x00,       /*  __u8  if_iInterface; */
 268
 269         /* one endpoint (status change endpoint) */
 270         0x07,       /*  __u8  ep_bLength; */
 271         USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 272         0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 273         0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 274         0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
 275         0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
 276 };
 277
 278 static const u8 hs_rh_config_descriptor[] = {
 279
 280         /* one configuration */
 281         0x09,       /*  __u8  bLength; */
 282         USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 283         0x19, 0x00, /*  __le16 wTotalLength; */
 284         0x01,       /*  __u8  bNumInterfaces; (1) */
 285         0x01,       /*  __u8  bConfigurationValue; */
 286         0x00,       /*  __u8  iConfiguration; */
 287         0xc0,       /*  __u8  bmAttributes;
 288                                  Bit 7: must be set,
 289                                      6: Self-powered,
 290                                      5: Remote wakeup,
 291                                      4..0: resvd */
 292         0x00,       /*  __u8  MaxPower; */
 293
 294         /* USB 1.1:
 295          * USB 2.0, single TT organization (mandatory):
 296          *      one interface, protocol 0
 297          *
 298          * USB 2.0, multiple TT organization (optional):
 299          *      two interfaces, protocols 1 (like single TT)
 300          *      and 2 (multiple TT mode) ... config is
 301          *      sometimes settable
 302          *      NOT IMPLEMENTED
 303          */
 304
 305         /* one interface */
 306         0x09,       /*  __u8  if_bLength; */
 307         USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
 308         0x00,       /*  __u8  if_bInterfaceNumber; */
 309         0x00,       /*  __u8  if_bAlternateSetting; */
 310         0x01,       /*  __u8  if_bNumEndpoints; */
 311         0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 312         0x00,       /*  __u8  if_bInterfaceSubClass; */
 313         0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 314         0x00,       /*  __u8  if_iInterface; */
 315
 316         /* one endpoint (status change endpoint) */
 317         0x07,       /*  __u8  ep_bLength; */
 318         USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 319         0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 320         0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 321                     /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 322                      * see hub.c:hub_configure() for details. */
 323         (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 324         0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 325 };
 326
 327 static const u8 ss_rh_config_descriptor[] = {
 328         /* one configuration */
 329         0x09,       /*  __u8  bLength; */
 330         USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 331         0x1f, 0x00, /*  __le16 wTotalLength; */
 332         0x01,       /*  __u8  bNumInterfaces; (1) */
 333         0x01,       /*  __u8  bConfigurationValue; */
 334         0x00,       /*  __u8  iConfiguration; */
 335         0xc0,       /*  __u8  bmAttributes;
 336                                  Bit 7: must be set,
 337                                      6: Self-powered,
 338                                      5: Remote wakeup,
 339                                      4..0: resvd */
 340         0x00,       /*  __u8  MaxPower; */
 341
 342         /* one interface */
 343         0x09,       /*  __u8  if_bLength; */
 344         USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
 345         0x00,       /*  __u8  if_bInterfaceNumber; */
 346         0x00,       /*  __u8  if_bAlternateSetting; */
 347         0x01,       /*  __u8  if_bNumEndpoints; */
 348         0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 349         0x00,       /*  __u8  if_bInterfaceSubClass; */
 350         0x00,       /*  __u8  if_bInterfaceProtocol; */
 351         0x00,       /*  __u8  if_iInterface; */
 352
 353         /* one endpoint (status change endpoint) */
 354         0x07,       /*  __u8  ep_bLength; */
 355         USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 356         0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 357         0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 358                     /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 359                      * see hub.c:hub_configure() for details. */
 360         (USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 361         0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 362
 363         /* one SuperSpeed endpoint companion descriptor */
 364         0x06,        /* __u8 ss_bLength */
 365         USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
 366                      /* Companion */
 367         0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
 368         0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
 369         0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
 370 };
 371
 372 /* authorized_default behaviour:
 373  * -1 is authorized for all devices except wireless (old behaviour)
 374  * 0 is unauthorized for all devices
 375  * 1 is authorized for all devices
 376  */
 377 static int authorized_default = -1;
 378 module_param(authorized_default, int, S_IRUGO|S_IWUSR);
 379 MODULE_PARM_DESC(authorized_default,
 380                 "Default USB device authorization: 0 is not authorized, 1 is "
 381                 "authorized, -1 is authorized except for wireless USB (default, "
 382                 "old behaviour");
 383 /*-------------------------------------------------------------------------*/
 384
 385 /**
 386  * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
 387  * @s: Null-terminated ASCII (actually ISO-8859-1) string
 388  * @buf: Buffer for USB string descriptor (header + UTF-16LE)
 389  * @len: Length (in bytes; may be odd) of descriptor buffer.
 390  *
 391  * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
 392  * whichever is less.
 393  *
 394  * Note:
 395  * USB String descriptors can contain at most 126 characters; input
 396  * strings longer than that are truncated.
 397  */
 398 static unsigned
 399 ascii2desc(char const *s, u8 *buf, unsigned len)
 400 {
 401         unsigned n, t = 2 + 2*strlen(s);
 402
 403         if (t > 254)
 404                 t = 254;        /* Longest possible UTF string descriptor */
 405         if (len > t)
 406                 len = t;
 407
 408         t += USB_DT_STRING << 8;        /* Now t is first 16 bits to store */
 409
 410         n = len;
 411         while (n--) {
 412                 *buf++ = t;
 413                 if (!n--)
 414                         break;
 415                 *buf++ = t >> 8;
 416                 t = (unsigned char)*s++;
 417         }
 418         return len;
 419 }
 420
 421 /**
 422  * rh_string() - provides string descriptors for root hub
 423  * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
 424  * @hcd: the host controller for this root hub
 425  * @data: buffer for output packet
 426  * @len: length of the provided buffer
 427  *
 428  * Produces either a manufacturer, product or serial number string for the
 429  * virtual root hub device.
 430  *
 431  * Return: The number of bytes filled in: the length of the descriptor or
 432  * of the provided buffer, whichever is less.
 433  */
 434 static unsigned
 435 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
 436 {
 437         char buf[100];
 438         char const *s;
 439         static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
 440
 441         /* language ids */
 442         switch (id) {
 443         case 0:
 444                 /* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
 445                 /* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
 446                 if (len > 4)
 447                         len = 4;
 448                 memcpy(data, langids, len);
 449                 return len;
 450         case 1:
 451                 /* Serial number */
 452                 s = hcd->self.bus_name;
 453                 break;
 454         case 2:
 455                 /* Product name */
 456                 s = hcd->product_desc;
 457                 break;
 458         case 3:
 459                 /* Manufacturer */
 460                 snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
 461                         init_utsname()->release, hcd->driver->description);
 462                 s = buf;
 463                 break;
 464         default:
 465                 /* Can't happen; caller guarantees it */
 466                 return 0;
 467         }
 468
 469         return ascii2desc(s, data, len);
 470 }
 471
 472
 473 /* Root hub control transfers execute synchronously */
 474 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
 475 {
 476         struct usb_ctrlrequest *cmd;
 477         u16             typeReq, wValue, wIndex, wLength;
 478         u8              *ubuf = urb->transfer_buffer;
 479         unsigned        len = 0;
 480         int             status;
 481         u8              patch_wakeup = 0;
 482         u8              patch_protocol = 0;
 483         u16             tbuf_size;
 484         u8              *tbuf = NULL;
 485         const u8        *bufp;
 486
 487         might_sleep();
 488
 489         spin_lock_irq(&hcd_root_hub_lock);
 490         status = usb_hcd_link_urb_to_ep(hcd, urb);
 491         spin_unlock_irq(&hcd_root_hub_lock);
 492         if (status)
 493                 return status;
 494         urb->hcpriv = hcd;      /* Indicate it's queued */
 495
 496         cmd = (struct usb_ctrlrequest *) urb->setup_packet;
 497         typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
 498         wValue   = le16_to_cpu (cmd->wValue);
 499         wIndex   = le16_to_cpu (cmd->wIndex);
 500         wLength  = le16_to_cpu (cmd->wLength);
 501
 502         if (wLength > urb->transfer_buffer_length)
 503                 goto error;
 504
 505         /*
 506          * tbuf should be at least as big as the
 507          * USB hub descriptor.
 508          */
 509         tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
 510         tbuf = kzalloc(tbuf_size, GFP_KERNEL);
 511         if (!tbuf) {
 512                 status = -ENOMEM;
 513                 goto err_alloc;
 514         }
 515
 516         bufp = tbuf;
 517
 518
 519         urb->actual_length = 0;
 520         switch (typeReq) {
 521
 522         /* DEVICE REQUESTS */
 523
 524         /* The root hub's remote wakeup enable bit is implemented using
 525          * driver model wakeup flags.  If this system supports wakeup
 526          * through USB, userspace may change the default "allow wakeup"
 527          * policy through sysfs or these calls.
 528          *
 529          * Most root hubs support wakeup from downstream devices, for
 530          * runtime power management (disabling USB clocks and reducing
 531          * VBUS power usage).  However, not all of them do so; silicon,
 532          * board, and BIOS bugs here are not uncommon, so these can't
 533          * be treated quite like external hubs.
 534          *
 535          * Likewise, not all root hubs will pass wakeup events upstream,
 536          * to wake up the whole system.  So don't assume root hub and
 537          * controller capabilities are identical.
 538          */
 539
 540         case DeviceRequest | USB_REQ_GET_STATUS:
 541                 tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
 542                                         << USB_DEVICE_REMOTE_WAKEUP)
 543                                 | (1 << USB_DEVICE_SELF_POWERED);
 544                 tbuf[1] = 0;
 545                 len = 2;
 546                 break;
 547         case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
 548                 if (wValue == USB_DEVICE_REMOTE_WAKEUP)
 549                         device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
 550                 else
 551                         goto error;
 552                 break;
 553         case DeviceOutRequest | USB_REQ_SET_FEATURE:
 554                 if (device_can_wakeup(&hcd->self.root_hub->dev)
 555                                 && wValue == USB_DEVICE_REMOTE_WAKEUP)
 556                         device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
 557                 else
 558                         goto error;
 559                 break;
 560         case DeviceRequest | USB_REQ_GET_CONFIGURATION:
 561                 tbuf[0] = 1;
 562                 len = 1;
 563                         /* FALLTHROUGH */
 564         case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
 565                 break;
 566         case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 567                 switch (wValue & 0xff00) {
 568                 case USB_DT_DEVICE << 8:
 569                         switch (hcd->speed) {
 570                         case HCD_USB32:
 571                         case HCD_USB31:
 572                                 bufp = usb31_rh_dev_descriptor;
 573                                 break;
 574                         case HCD_USB3:
 575                                 bufp = usb3_rh_dev_descriptor;
 576                                 break;
 577                         case HCD_USB25:
 578                                 bufp = usb25_rh_dev_descriptor;
 579                                 break;
 580                         case HCD_USB2:
 581                                 bufp = usb2_rh_dev_descriptor;
 582                                 break;
 583                         case HCD_USB11:
 584                                 bufp = usb11_rh_dev_descriptor;
 585                                 break;
 586                         default:
 587                                 goto error;
 588                         }
 589                         len = 18;
 590                         if (hcd->has_tt)
 591                                 patch_protocol = 1;
 592                         break;
 593                 case USB_DT_CONFIG << 8:
 594                         switch (hcd->speed) {
 595                         case HCD_USB32:
 596                         case HCD_USB31:
 597                         case HCD_USB3:
 598                                 bufp = ss_rh_config_descriptor;
 599                                 len = sizeof ss_rh_config_descriptor;
 600                                 break;
 601                         case HCD_USB25:
 602                         case HCD_USB2:
 603                                 bufp = hs_rh_config_descriptor;
 604                                 len = sizeof hs_rh_config_descriptor;
 605                                 break;
 606                         case HCD_USB11:
 607                                 bufp = fs_rh_config_descriptor;
 608                                 len = sizeof fs_rh_config_descriptor;
 609                                 break;
 610                         default:
 611                                 goto error;
 612                         }
 613                         if (device_can_wakeup(&hcd->self.root_hub->dev))
 614                                 patch_wakeup = 1;
 615                         break;
 616                 case USB_DT_STRING << 8:
 617                         if ((wValue & 0xff) < 4)
 618                                 urb->actual_length = rh_string(wValue & 0xff,
 619                                                 hcd, ubuf, wLength);
 620                         else /* unsupported IDs --> "protocol stall" */
 621                                 goto error;
 622                         break;
 623                 case USB_DT_BOS << 8:
 624                         goto nongeneric;
 625                 default:
 626                         goto error;
 627                 }
 628                 break;
 629         case DeviceRequest | USB_REQ_GET_INTERFACE:
 630                 tbuf[0] = 0;
 631                 len = 1;
 632                         /* FALLTHROUGH */
 633         case DeviceOutRequest | USB_REQ_SET_INTERFACE:
 634                 break;
 635         case DeviceOutRequest | USB_REQ_SET_ADDRESS:
 636                 /* wValue == urb->dev->devaddr */
 637                 dev_dbg (hcd->self.controller, "root hub device address %d\n",
 638                         wValue);
 639                 break;
 640
 641         /* INTERFACE REQUESTS (no defined feature/status flags) */
 642
 643         /* ENDPOINT REQUESTS */
 644
 645         case EndpointRequest | USB_REQ_GET_STATUS:
 646                 /* ENDPOINT_HALT flag */
 647                 tbuf[0] = 0;
 648                 tbuf[1] = 0;
 649                 len = 2;
 650                         /* FALLTHROUGH */
 651         case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
 652         case EndpointOutRequest | USB_REQ_SET_FEATURE:
 653                 dev_dbg (hcd->self.controller, "no endpoint features yet\n");
 654                 break;
 655
 656         /* CLASS REQUESTS (and errors) */
 657
 658         default:
 659 nongeneric:
 660                 /* non-generic request */
 661                 switch (typeReq) {
 662                 case GetHubStatus:
 663                         len = 4;
 664                         break;
 665                 case GetPortStatus:
 666                         if (wValue == HUB_PORT_STATUS)
 667                                 len = 4;
 668                         else
 669                                 /* other port status types return 8 bytes */
 670                                 len = 8;
 671                         break;
 672                 case GetHubDescriptor:
 673                         len = sizeof (struct usb_hub_descriptor);
 674                         break;
 675                 case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 676                         /* len is returned by hub_control */
 677                         break;
 678                 }
 679                 status = hcd->driver->hub_control (hcd,
 680                         typeReq, wValue, wIndex,
 681                         tbuf, wLength);
 682
 683                 if (typeReq == GetHubDescriptor)
 684                         usb_hub_adjust_deviceremovable(hcd->self.root_hub,
 685                                 (struct usb_hub_descriptor *)tbuf);
 686                 break;
 687 error:
 688                 /* "protocol stall" on error */
 689                 status = -EPIPE;
 690         }
 691
 692         if (status < 0) {
 693                 len = 0;
 694                 if (status != -EPIPE) {
 695                         dev_dbg (hcd->self.controller,
 696                                 "CTRL: TypeReq=0x%x val=0x%x "
 697                                 "idx=0x%x len=%d ==> %d\n",
 698                                 typeReq, wValue, wIndex,
 699                                 wLength, status);
 700                 }
 701         } else if (status > 0) {
 702                 /* hub_control may return the length of data copied. */
 703                 len = status;
 704                 status = 0;
 705         }
 706         if (len) {
 707                 if (urb->transfer_buffer_length < len)
 708                         len = urb->transfer_buffer_length;
 709                 urb->actual_length = len;
 710                 /* always USB_DIR_IN, toward host */
 711                 memcpy (ubuf, bufp, len);
 712
 713                 /* report whether RH hardware supports remote wakeup */
 714                 if (patch_wakeup &&
 715                                 len > offsetof (struct usb_config_descriptor,
 716                                                 bmAttributes))
 717                         ((struct usb_config_descriptor *)ubuf)->bmAttributes
 718                                 |= USB_CONFIG_ATT_WAKEUP;
 719
 720                 /* report whether RH hardware has an integrated TT */
 721                 if (patch_protocol &&
 722                                 len > offsetof(struct usb_device_descriptor,
 723                                                 bDeviceProtocol))
 724                         ((struct usb_device_descriptor *) ubuf)->
 725                                 bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
 726         }
 727
 728         kfree(tbuf);
 729  err_alloc:
 730
 731         /* any errors get returned through the urb completion */
 732         spin_lock_irq(&hcd_root_hub_lock);
 733         usb_hcd_unlink_urb_from_ep(hcd, urb);
 734         usb_hcd_giveback_urb(hcd, urb, status);
 735         spin_unlock_irq(&hcd_root_hub_lock);
 736         return 0;
 737 }
 738
 739 /*-------------------------------------------------------------------------*/
 740
 741 /*
 742  * Root Hub interrupt transfers are polled using a timer if the
 743  * driver requests it; otherwise the driver is responsible for
 744  * calling usb_hcd_poll_rh_status() when an event occurs.
 745  *
 746  * Completions are called in_interrupt(), but they may or may not
 747  * be in_irq().
 748  */
 749 void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
 750 {
 751         struct urb      *urb;
 752         int             length;
 753         int             status;
 754         unsigned long   flags;
 755         char            buffer[6];      /* Any root hubs with > 31 ports? */
 756
 757         if (unlikely(!hcd->rh_pollable))
 758                 return;
 759         if (!hcd->uses_new_polling && !hcd->status_urb)
 760                 return;
 761
 762         length = hcd->driver->hub_status_data(hcd, buffer);
 763         if (length > 0) {
 764
 765                 /* try to complete the status urb */
 766                 spin_lock_irqsave(&hcd_root_hub_lock, flags);
 767                 urb = hcd->status_urb;
 768                 if (urb) {
 769                         clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 770                         hcd->status_urb = NULL;
 771                         if (urb->transfer_buffer_length >= length) {
 772                                 status = 0;
 773                         } else {
 774                                 status = -EOVERFLOW;
 775                                 length = urb->transfer_buffer_length;
 776                         }
 777                         urb->actual_length = length;
 778                         memcpy(urb->transfer_buffer, buffer, length);
 779
 780                         usb_hcd_unlink_urb_from_ep(hcd, urb);
 781                         usb_hcd_giveback_urb(hcd, urb, status);
 782                 } else {
 783                         length = 0;
 784                         set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 785                 }
 786                 spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 787         }
 788
 789         /* The USB 2.0 spec says 256 ms.  This is close enough and won't
 790          * exceed that limit if HZ is 100. The math is more clunky than
 791          * maybe expected, this is to make sure that all timers for USB devices
 792          * fire at the same time to give the CPU a break in between */
 793         if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
 794                         (length == 0 && hcd->status_urb != NULL))
 795                 mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 796 }
 797 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
 798
 799 /* timer callback */
 800 static void rh_timer_func (struct timer_list *t)
 801 {
 802         struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
 803
 804         usb_hcd_poll_rh_status(_hcd);
 805 }
 806
 807 /*-------------------------------------------------------------------------*/
 808
 809 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
 810 {
 811         int             retval;
 812         unsigned long   flags;
 813         unsigned        len = 1 + (urb->dev->maxchild / 8);
 814
 815         spin_lock_irqsave (&hcd_root_hub_lock, flags);
 816         if (hcd->status_urb || urb->transfer_buffer_length < len) {
 817                 dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
 818                 retval = -EINVAL;
 819                 goto done;
 820         }
 821
 822         retval = usb_hcd_link_urb_to_ep(hcd, urb);
 823         if (retval)
 824                 goto done;
 825
 826         hcd->status_urb = urb;
 827         urb->hcpriv = hcd;      /* indicate it's queued */
 828         if (!hcd->uses_new_polling)
 829                 mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 830
 831         /* If a status change has already occurred, report it ASAP */
 832         else if (HCD_POLL_PENDING(hcd))
 833                 mod_timer(&hcd->rh_timer, jiffies);
 834         retval = 0;
 835  done:
 836         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
 837         return retval;
 838 }
 839
 840 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
 841 {
 842         if (usb_endpoint_xfer_int(&urb->ep->desc))
 843                 return rh_queue_status (hcd, urb);
 844         if (usb_endpoint_xfer_control(&urb->ep->desc))
 845                 return rh_call_control (hcd, urb);
 846         return -EINVAL;
 847 }
 848
 849 /*-------------------------------------------------------------------------*/
 850
 851 /* Unlinks of root-hub control URBs are legal, but they don't do anything
 852  * since these URBs always execute synchronously.
 853  */
 854 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 855 {
 856         unsigned long   flags;
 857         int             rc;
 858
 859         spin_lock_irqsave(&hcd_root_hub_lock, flags);
 860         rc = usb_hcd_check_unlink_urb(hcd, urb, status);
 861         if (rc)
 862                 goto done;
 863
 864         if (usb_endpoint_num(&urb->ep->desc) == 0) {    /* Control URB */
 865                 ;       /* Do nothing */
 866
 867         } else {                                /* Status URB */
 868                 if (!hcd->uses_new_polling)
 869                         del_timer (&hcd->rh_timer);
 870                 if (urb == hcd->status_urb) {
 871                         hcd->status_urb = NULL;
 872                         usb_hcd_unlink_urb_from_ep(hcd, urb);
 873                         usb_hcd_giveback_urb(hcd, urb, status);
 874                 }
 875         }
 876  done:
 877         spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 878         return rc;
 879 }
 880
 881
 882
 883 /*
 884  * Show & store the current value of authorized_default
 885  */
 886 static ssize_t authorized_default_show(struct device *dev,
 887                                        struct device_attribute *attr, char *buf)
 888 {
 889         struct usb_device *rh_usb_dev = to_usb_device(dev);
 890         struct usb_bus *usb_bus = rh_usb_dev->bus;
 891         struct usb_hcd *hcd;
 892
 893         hcd = bus_to_hcd(usb_bus);
 894         return snprintf(buf, PAGE_SIZE, "%u\n", !!HCD_DEV_AUTHORIZED(hcd));
 895 }
 896
 897 static ssize_t authorized_default_store(struct device *dev,
 898                                         struct device_attribute *attr,
 899                                         const char *buf, size_t size)
 900 {
 901         ssize_t result;
 902         unsigned val;
 903         struct usb_device *rh_usb_dev = to_usb_device(dev);
 904         struct usb_bus *usb_bus = rh_usb_dev->bus;
 905         struct usb_hcd *hcd;
 906
 907         hcd = bus_to_hcd(usb_bus);
 908         result = sscanf(buf, "%u\n", &val);
 909         if (result == 1) {
 910                 if (val)
 911                         set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
 912                 else
 913                         clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
 914
 915                 result = size;
 916         } else {
 917                 result = -EINVAL;
 918         }
 919         return result;
 920 }
 921 static DEVICE_ATTR_RW(authorized_default);
 922
 923 /*
 924  * interface_authorized_default_show - show default authorization status
 925  * for USB interfaces
 926  *
 927  * note: interface_authorized_default is the default value
 928  *       for initializing the authorized attribute of interfaces
 929  */
 930 static ssize_t interface_authorized_default_show(struct device *dev,
 931                 struct device_attribute *attr, char *buf)
 932 {
 933         struct usb_device *usb_dev = to_usb_device(dev);
 934         struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
 935
 936         return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
 937 }
 938
 939 /*
 940  * interface_authorized_default_store - store default authorization status
 941  * for USB interfaces
 942  *
 943  * note: interface_authorized_default is the default value
 944  *       for initializing the authorized attribute of interfaces
 945  */
 946 static ssize_t interface_authorized_default_store(struct device *dev,
 947                 struct device_attribute *attr, const char *buf, size_t count)
 948 {
 949         struct usb_device *usb_dev = to_usb_device(dev);
 950         struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
 951         int rc = count;
 952         bool val;
 953
 954         if (strtobool(buf, &val) != 0)
 955                 return -EINVAL;
 956
 957         if (val)
 958                 set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
 959         else
 960                 clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
 961
 962         return rc;
 963 }
 964 static DEVICE_ATTR_RW(interface_authorized_default);
 965
 966 /* Group all the USB bus attributes */
 967 static struct attribute *usb_bus_attrs[] = {
 968                 &dev_attr_authorized_default.attr,
 969                 &dev_attr_interface_authorized_default.attr,
 970                 NULL,
 971 };
 972
 973 static const struct attribute_group usb_bus_attr_group = {
 974         .name = NULL,   /* we want them in the same directory */
 975         .attrs = usb_bus_attrs,
 976 };
 977
 978
 979
 980 /*-------------------------------------------------------------------------*/
 981
 982 /**
 983  * usb_bus_init - shared initialization code
 984  * @bus: the bus structure being initialized
 985  *
 986  * This code is used to initialize a usb_bus structure, memory for which is
 987  * separately managed.
 988  */
 989 static void usb_bus_init (struct usb_bus *bus)
 990 {
 991         memset (&bus->devmap, 0, sizeof(struct usb_devmap));
 992
 993         bus->devnum_next = 1;
 994
 995         bus->root_hub = NULL;
 996         bus->busnum = -1;
 997         bus->bandwidth_allocated = 0;
 998         bus->bandwidth_int_reqs  = 0;
 999         bus->bandwidth_isoc_reqs = 0;
1000         mutex_init(&bus->devnum_next_mutex);
1001 }
1002
1003 /*-------------------------------------------------------------------------*/
1004
1005 /**
1006  * usb_register_bus - registers the USB host controller with the usb core
1007  * @bus: pointer to the bus to register
1008  * Context: !in_interrupt()
1009  *
1010  * Assigns a bus number, and links the controller into usbcore data
1011  * structures so that it can be seen by scanning the bus list.
1012  *
1013  * Return: 0 if successful. A negative error code otherwise.
1014  */
1015 static int usb_register_bus(struct usb_bus *bus)
1016 {
1017         int result = -E2BIG;
1018         int busnum;
1019
1020         mutex_lock(&usb_bus_idr_lock);
1021         busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
1022         if (busnum < 0) {
1023                 pr_err("%s: failed to get bus number\n", usbcore_name);
1024                 goto error_find_busnum;
1025         }
1026         bus->busnum = busnum;
1027         mutex_unlock(&usb_bus_idr_lock);
1028
1029         usb_notify_add_bus(bus);
1030
1031         dev_info (bus->controller, "new USB bus registered, assigned bus "
1032                   "number %d\n", bus->busnum);
1033         return 0;
1034
1035 error_find_busnum:
1036         mutex_unlock(&usb_bus_idr_lock);
1037         return result;
1038 }
1039
1040 /**
1041  * usb_deregister_bus - deregisters the USB host controller
1042  * @bus: pointer to the bus to deregister
1043  * Context: !in_interrupt()
1044  *
1045  * Recycles the bus number, and unlinks the controller from usbcore data
1046  * structures so that it won't be seen by scanning the bus list.
1047  */
1048 static void usb_deregister_bus (struct usb_bus *bus)
1049 {
1050         dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
1051
1052         /*
1053          * NOTE: make sure that all the devices are removed by the
1054          * controller code, as well as having it call this when cleaning
1055          * itself up
1056          */
1057         mutex_lock(&usb_bus_idr_lock);
1058         idr_remove(&usb_bus_idr, bus->busnum);
1059         mutex_unlock(&usb_bus_idr_lock);
1060
1061         usb_notify_remove_bus(bus);
1062 }
1063
1064 /**
1065  * register_root_hub - called by usb_add_hcd() to register a root hub
1066  * @hcd: host controller for this root hub
1067  *
1068  * This function registers the root hub with the USB subsystem.  It sets up
1069  * the device properly in the device tree and then calls usb_new_device()
1070  * to register the usb device.  It also assigns the root hub's USB address
1071  * (always 1).
1072  *
1073  * Return: 0 if successful. A negative error code otherwise.
1074  */
1075 static int register_root_hub(struct usb_hcd *hcd)
1076 {
1077         struct device *parent_dev = hcd->self.controller;
1078         struct usb_device *usb_dev = hcd->self.root_hub;
1079         const int devnum = 1;
1080         int retval;
1081
1082         usb_dev->devnum = devnum;
1083         usb_dev->bus->devnum_next = devnum + 1;
1084         memset (&usb_dev->bus->devmap.devicemap, 0,
1085                         sizeof usb_dev->bus->devmap.devicemap);
1086         set_bit (devnum, usb_dev->bus->devmap.devicemap);
1087         usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
1088
1089         mutex_lock(&usb_bus_idr_lock);
1090
1091         usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
1092         retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
1093         if (retval != sizeof usb_dev->descriptor) {
1094                 mutex_unlock(&usb_bus_idr_lock);
1095                 dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
1096                                 dev_name(&usb_dev->dev), retval);
1097                 return (retval < 0) ? retval : -EMSGSIZE;
1098         }
1099
1100         if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
1101                 retval = usb_get_bos_descriptor(usb_dev);
1102                 if (!retval) {
1103                         usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1104                 } else if (usb_dev->speed >= USB_SPEED_SUPER) {
1105                         mutex_unlock(&usb_bus_idr_lock);
1106                         dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1107                                         dev_name(&usb_dev->dev), retval);
1108                         return retval;
1109                 }
1110         }
1111
1112         retval = usb_new_device (usb_dev);
1113         if (retval) {
1114                 dev_err (parent_dev, "can't register root hub for %s, %d\n",
1115                                 dev_name(&usb_dev->dev), retval);
1116         } else {
1117                 spin_lock_irq (&hcd_root_hub_lock);
1118                 hcd->rh_registered = 1;
1119                 spin_unlock_irq (&hcd_root_hub_lock);
1120
1121                 /* Did the HC die before the root hub was registered? */
1122                 if (HCD_DEAD(hcd))
1123                         usb_hc_died (hcd);      /* This time clean up */
1124         }
1125         mutex_unlock(&usb_bus_idr_lock);
1126
1127         return retval;
1128 }
1129
1130 /*
1131  * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1132  * @bus: the bus which the root hub belongs to
1133  * @portnum: the port which is being resumed
1134  *
1135  * HCDs should call this function when they know that a resume signal is
1136  * being sent to a root-hub port.  The root hub will be prevented from
1137  * going into autosuspend until usb_hcd_end_port_resume() is called.
1138  *
1139  * The bus's private lock must be held by the caller.
1140  */
1141 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1142 {
1143         unsigned bit = 1 << portnum;
1144
1145         if (!(bus->resuming_ports & bit)) {
1146                 bus->resuming_ports |= bit;
1147                 pm_runtime_get_noresume(&bus->root_hub->dev);
1148         }
1149 }
1150 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1151
1152 /*
1153  * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1154  * @bus: the bus which the root hub belongs to
1155  * @portnum: the port which is being resumed
1156  *
1157  * HCDs should call this function when they know that a resume signal has
1158  * stopped being sent to a root-hub port.  The root hub will be allowed to
1159  * autosuspend again.
1160  *
1161  * The bus's private lock must be held by the caller.
1162  */
1163 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1164 {
1165         unsigned bit = 1 << portnum;
1166
1167         if (bus->resuming_ports & bit) {
1168                 bus->resuming_ports &= ~bit;
1169                 pm_runtime_put_noidle(&bus->root_hub->dev);
1170         }
1171 }
1172 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1173
1174 /*-------------------------------------------------------------------------*/
1175
1176 /**
1177  * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1178  * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1179  * @is_input: true iff the transaction sends data to the host
1180  * @isoc: true for isochronous transactions, false for interrupt ones
1181  * @bytecount: how many bytes in the transaction.
1182  *
1183  * Return: Approximate bus time in nanoseconds for a periodic transaction.
1184  *
1185  * Note:
1186  * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1187  * scheduled in software, this function is only used for such scheduling.
1188  */
1189 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1190 {
1191         unsigned long   tmp;
1192
1193         switch (speed) {
1194         case USB_SPEED_LOW:     /* INTR only */
1195                 if (is_input) {
1196                         tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1197                         return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1198                 } else {
1199                         tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1200                         return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1201                 }
1202         case USB_SPEED_FULL:    /* ISOC or INTR */
1203                 if (isoc) {
1204                         tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1205                         return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1206                 } else {
1207                         tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1208                         return 9107L + BW_HOST_DELAY + tmp;
1209                 }
1210         case USB_SPEED_HIGH:    /* ISOC or INTR */
1211                 /* FIXME adjust for input vs output */
1212                 if (isoc)
1213                         tmp = HS_NSECS_ISO (bytecount);
1214                 else
1215                         tmp = HS_NSECS (bytecount);
1216                 return tmp;
1217         default:
1218                 pr_debug ("%s: bogus device speed!\n", usbcore_name);
1219                 return -1;
1220         }
1221 }
1222 EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1223
1224
1225 /*-------------------------------------------------------------------------*/
1226
1227 /*
1228  * Generic HC operations.
1229  */
1230
1231 /*-------------------------------------------------------------------------*/
1232
1233 /**
1234  * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1235  * @hcd: host controller to which @urb was submitted
1236  * @urb: URB being submitted
1237  *
1238  * Host controller drivers should call this routine in their enqueue()
1239  * method.  The HCD's private spinlock must be held and interrupts must
1240  * be disabled.  The actions carried out here are required for URB
1241  * submission, as well as for endpoint shutdown and for usb_kill_urb.
1242  *
1243  * Return: 0 for no error, otherwise a negative error code (in which case
1244  * the enqueue() method must fail).  If no error occurs but enqueue() fails
1245  * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1246  * the private spinlock and returning.
1247  */
1248 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1249 {
1250         int             rc = 0;
1251
1252         spin_lock(&hcd_urb_list_lock);
1253
1254         /* Check that the URB isn't being killed */
1255         if (unlikely(atomic_read(&urb->reject))) {
1256                 rc = -EPERM;
1257                 goto done;
1258         }
1259
1260         if (unlikely(!urb->ep->enabled)) {
1261                 rc = -ENOENT;
1262                 goto done;
1263         }
1264
1265         if (unlikely(!urb->dev->can_submit)) {
1266                 rc = -EHOSTUNREACH;
1267                 goto done;
1268         }
1269
1270         /*
1271          * Check the host controller's state and add the URB to the
1272          * endpoint's queue.
1273          */
1274         if (HCD_RH_RUNNING(hcd)) {
1275                 urb->unlinked = 0;
1276                 list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1277         } else {
1278                 rc = -ESHUTDOWN;
1279                 goto done;
1280         }
1281  done:
1282         spin_unlock(&hcd_urb_list_lock);
1283         return rc;
1284 }
1285 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1286
1287 /**
1288  * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1289  * @hcd: host controller to which @urb was submitted
1290  * @urb: URB being checked for unlinkability
1291  * @status: error code to store in @urb if the unlink succeeds
1292  *
1293  * Host controller drivers should call this routine in their dequeue()
1294  * method.  The HCD's private spinlock must be held and interrupts must
1295  * be disabled.  The actions carried out here are required for making
1296  * sure than an unlink is valid.
1297  *
1298  * Return: 0 for no error, otherwise a negative error code (in which case
1299  * the dequeue() method must fail).  The possible error codes are:
1300  *
1301  *      -EIDRM: @urb was not submitted or has already completed.
1302  *              The completion function may not have been called yet.
1303  *
1304  *      -EBUSY: @urb has already been unlinked.
1305  */
1306 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1307                 int status)
1308 {
1309         struct list_head        *tmp;
1310
1311         /* insist the urb is still queued */
1312         list_for_each(tmp, &urb->ep->urb_list) {
1313                 if (tmp == &urb->urb_list)
1314                         break;
1315         }
1316         if (tmp != &urb->urb_list)
1317                 return -EIDRM;
1318
1319         /* Any status except -EINPROGRESS means something already started to
1320          * unlink this URB from the hardware.  So there's no more work to do.
1321          */
1322         if (urb->unlinked)
1323                 return -EBUSY;
1324         urb->unlinked = status;
1325         return 0;
1326 }
1327 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1328
1329 /**
1330  * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1331  * @hcd: host controller to which @urb was submitted
1332  * @urb: URB being unlinked
1333  *
1334  * Host controller drivers should call this routine before calling
1335  * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1336  * interrupts must be disabled.  The actions carried out here are required
1337  * for URB completion.
1338  */
1339 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1340 {
1341         /* clear all state linking urb to this dev (and hcd) */
1342         spin_lock(&hcd_urb_list_lock);
1343         list_del_init(&urb->urb_list);
1344         spin_unlock(&hcd_urb_list_lock);
1345 }
1346 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1347
1348 /*
1349  * Some usb host controllers can only perform dma using a small SRAM area.
1350  * The usb core itself is however optimized for host controllers that can dma
1351  * using regular system memory - like pci devices doing bus mastering.
1352  *
1353  * To support host controllers with limited dma capabilities we provide dma
1354  * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
1355  * For this to work properly the host controller code must first use the
1356  * function dma_declare_coherent_memory() to point out which memory area
1357  * that should be used for dma allocations.
1358  *
1359  * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
1360  * dma using dma_alloc_coherent() which in turn allocates from the memory
1361  * area pointed out with dma_declare_coherent_memory().
1362  *
1363  * So, to summarize...
1364  *
1365  * - We need "local" memory, canonical example being
1366  *   a small SRAM on a discrete controller being the
1367  *   only memory that the controller can read ...
1368  *   (a) "normal" kernel memory is no good, and
1369  *   (b) there's not enough to share
1370  *
1371  * - The only *portable* hook for such stuff in the
1372  *   DMA framework is dma_declare_coherent_memory()
1373  *
1374  * - So we use that, even though the primary requirement
1375  *   is that the memory be "local" (hence addressable
1376  *   by that device), not "coherent".
1377  *
1378  */
1379
1380 static int hcd_alloc_coherent(struct usb_bus *bus,
1381                               gfp_t mem_flags, dma_addr_t *dma_handle,
1382                               void **vaddr_handle, size_t size,
1383                               enum dma_data_direction dir)
1384 {
1385         unsigned char *vaddr;
1386
1387         if (*vaddr_handle == NULL) {
1388                 WARN_ON_ONCE(1);
1389                 return -EFAULT;
1390         }
1391
1392         vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1393                                  mem_flags, dma_handle);
1394         if (!vaddr)
1395                 return -ENOMEM;
1396
1397         /*
1398          * Store the virtual address of the buffer at the end
1399          * of the allocated dma buffer. The size of the buffer
1400          * may be uneven so use unaligned functions instead
1401          * of just rounding up. It makes sense to optimize for
1402          * memory footprint over access speed since the amount
1403          * of memory available for dma may be limited.
1404          */
1405         put_unaligned((unsigned long)*vaddr_handle,
1406                       (unsigned long *)(vaddr + size));
1407
1408         if (dir == DMA_TO_DEVICE)
1409                 memcpy(vaddr, *vaddr_handle, size);
1410
1411         *vaddr_handle = vaddr;
1412         return 0;
1413 }
1414
1415 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1416                               void **vaddr_handle, size_t size,
1417                               enum dma_data_direction dir)
1418 {
1419         unsigned char *vaddr = *vaddr_handle;
1420
1421         vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1422
1423         if (dir == DMA_FROM_DEVICE)
1424                 memcpy(vaddr, *vaddr_handle, size);
1425
1426         hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1427
1428         *vaddr_handle = vaddr;
1429         *dma_handle = 0;
1430 }
1431
1432 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1433 {
1434         if (IS_ENABLED(CONFIG_HAS_DMA) &&
1435             (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1436                 dma_unmap_single(hcd->self.sysdev,
1437                                 urb->setup_dma,
1438                                 sizeof(struct usb_ctrlrequest),
1439                                 DMA_TO_DEVICE);
1440         else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1441                 hcd_free_coherent(urb->dev->bus,
1442                                 &urb->setup_dma,
1443                                 (void **) &urb->setup_packet,
1444                                 sizeof(struct usb_ctrlrequest),
1445                                 DMA_TO_DEVICE);
1446
1447         /* Make it safe to call this routine more than once */
1448         urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1449 }
1450 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1451
1452 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1453 {
1454         if (hcd->driver->unmap_urb_for_dma)
1455                 hcd->driver->unmap_urb_for_dma(hcd, urb);
1456         else
1457                 usb_hcd_unmap_urb_for_dma(hcd, urb);
1458 }
1459
1460 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1461 {
1462         enum dma_data_direction dir;
1463
1464         usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1465
1466         dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1467         if (IS_ENABLED(CONFIG_HAS_DMA) &&
1468             (urb->transfer_flags & URB_DMA_MAP_SG))
1469                 dma_unmap_sg(hcd->self.sysdev,
1470                                 urb->sg,
1471                                 urb->num_sgs,
1472                                 dir);
1473         else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1474                  (urb->transfer_flags & URB_DMA_MAP_PAGE))
1475                 dma_unmap_page(hcd->self.sysdev,
1476                                 urb->transfer_dma,
1477                                 urb->transfer_buffer_length,
1478                                 dir);
1479         else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1480                  (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1481                 dma_unmap_single(hcd->self.sysdev,
1482                                 urb->transfer_dma,
1483                                 urb->transfer_buffer_length,
1484                                 dir);
1485         else if (urb->transfer_flags & URB_MAP_LOCAL)
1486                 hcd_free_coherent(urb->dev->bus,
1487                                 &urb->transfer_dma,
1488                                 &urb->transfer_buffer,
1489                                 urb->transfer_buffer_length,
1490                                 dir);
1491
1492         /* Make it safe to call this routine more than once */
1493         urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1494                         URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1495 }
1496 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1497
1498 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1499                            gfp_t mem_flags)
1500 {
1501         if (hcd->driver->map_urb_for_dma)
1502                 return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1503         else
1504                 return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1505 }
1506
1507 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1508                             gfp_t mem_flags)
1509 {
1510         enum dma_data_direction dir;
1511         int ret = 0;
1512
1513         /* Map the URB's buffers for DMA access.
1514          * Lower level HCD code should use *_dma exclusively,
1515          * unless it uses pio or talks to another transport,
1516          * or uses the provided scatter gather list for bulk.
1517          */
1518
1519         if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1520                 if (hcd->self.uses_pio_for_control)
1521                         return ret;
1522                 if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1523                         if (is_vmalloc_addr(urb->setup_packet)) {
1524                                 WARN_ONCE(1, "setup packet is not dma capable\n");
1525                                 return -EAGAIN;
1526                         } else if (object_is_on_stack(urb->setup_packet)) {
1527                                 WARN_ONCE(1, "setup packet is on stack\n");
1528                                 return -EAGAIN;
1529                         }
1530
1531                         urb->setup_dma = dma_map_single(
1532                                         hcd->self.sysdev,
1533                                         urb->setup_packet,
1534                                         sizeof(struct usb_ctrlrequest),
1535                                         DMA_TO_DEVICE);
1536                         if (dma_mapping_error(hcd->self.sysdev,
1537                                                 urb->setup_dma))
1538                                 return -EAGAIN;
1539                         urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1540                 } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1541                         ret = hcd_alloc_coherent(
1542                                         urb->dev->bus, mem_flags,
1543                                         &urb->setup_dma,
1544                                         (void **)&urb->setup_packet,
1545                                         sizeof(struct usb_ctrlrequest),
1546                                         DMA_TO_DEVICE);
1547                         if (ret)
1548                                 return ret;
1549                         urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1550                 }
1551         }
1552
1553         dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1554         if (urb->transfer_buffer_length != 0
1555             && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1556                 if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
1557                         if (urb->num_sgs) {
1558                                 int n;
1559
1560                                 /* We don't support sg for isoc transfers ! */
1561                                 if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1562                                         WARN_ON(1);
1563                                         return -EINVAL;
1564                                 }
1565
1566                                 n = dma_map_sg(
1567                                                 hcd->self.sysdev,
1568                                                 urb->sg,
1569                                                 urb->num_sgs,
1570                                                 dir);
1571                                 if (n <= 0)
1572                                         ret = -EAGAIN;
1573                                 else
1574                                         urb->transfer_flags |= URB_DMA_MAP_SG;
1575                                 urb->num_mapped_sgs = n;
1576                                 if (n != urb->num_sgs)
1577                                         urb->transfer_flags |=
1578                                                         URB_DMA_SG_COMBINED;
1579                         } else if (urb->sg) {
1580                                 struct scatterlist *sg = urb->sg;
1581                                 urb->transfer_dma = dma_map_page(
1582                                                 hcd->self.sysdev,
1583                                                 sg_page(sg),
1584                                                 sg->offset,
1585                                                 urb->transfer_buffer_length,
1586                                                 dir);
1587                                 if (dma_mapping_error(hcd->self.sysdev,
1588                                                 urb->transfer_dma))
1589                                         ret = -EAGAIN;
1590                                 else
1591                                         urb->transfer_flags |= URB_DMA_MAP_PAGE;
1592                         } else if (is_vmalloc_addr(urb->transfer_buffer)) {
1593                                 WARN_ONCE(1, "transfer buffer not dma capable\n");
1594                                 ret = -EAGAIN;
1595                         } else if (object_is_on_stack(urb->transfer_buffer)) {
1596                                 WARN_ONCE(1, "transfer buffer is on stack\n");
1597                                 ret = -EAGAIN;
1598                         } else {
1599                                 urb->transfer_dma = dma_map_single(
1600                                                 hcd->self.sysdev,
1601                                                 urb->transfer_buffer,
1602                                                 urb->transfer_buffer_length,
1603                                                 dir);
1604                                 if (dma_mapping_error(hcd->self.sysdev,
1605                                                 urb->transfer_dma))
1606                                         ret = -EAGAIN;
1607                                 else
1608                                         urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1609                         }
1610                 } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
1611                         ret = hcd_alloc_coherent(
1612                                         urb->dev->bus, mem_flags,
1613                                         &urb->transfer_dma,
1614                                         &urb->transfer_buffer,
1615                                         urb->transfer_buffer_length,
1616                                         dir);
1617                         if (ret == 0)
1618                                 urb->transfer_flags |= URB_MAP_LOCAL;
1619                 }
1620                 if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1621                                 URB_SETUP_MAP_LOCAL)))
1622                         usb_hcd_unmap_urb_for_dma(hcd, urb);
1623         }
1624         return ret;
1625 }
1626 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1627
1628 /*-------------------------------------------------------------------------*/
1629
1630 /* may be called in any context with a valid urb->dev usecount
1631  * caller surrenders "ownership" of urb
1632  * expects usb_submit_urb() to have sanity checked and conditioned all
1633  * inputs in the urb
1634  */
1635 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1636 {
1637         int                     status;
1638         struct usb_hcd          *hcd = bus_to_hcd(urb->dev->bus);
1639
1640         /* increment urb's reference count as part of giving it to the HCD
1641          * (which will control it).  HCD guarantees that it either returns
1642          * an error or calls giveback(), but not both.
1643          */
1644         usb_get_urb(urb);
1645         atomic_inc(&urb->use_count);
1646         atomic_inc(&urb->dev->urbnum);
1647         usbmon_urb_submit(&hcd->self, urb);
1648
1649         /* NOTE requirements on root-hub callers (usbfs and the hub
1650          * driver, for now):  URBs' urb->transfer_buffer must be
1651          * valid and usb_buffer_{sync,unmap}() not be needed, since
1652          * they could clobber root hub response data.  Also, control
1653          * URBs must be submitted in process context with interrupts
1654          * enabled.
1655          */
1656
1657         if (is_root_hub(urb->dev)) {
1658                 status = rh_urb_enqueue(hcd, urb);
1659         } else {
1660                 status = map_urb_for_dma(hcd, urb, mem_flags);
1661                 if (likely(status == 0)) {
1662                         status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1663                         if (unlikely(status))
1664                                 unmap_urb_for_dma(hcd, urb);
1665                 }
1666         }
1667
1668         if (unlikely(status)) {
1669                 usbmon_urb_submit_error(&hcd->self, urb, status);
1670                 urb->hcpriv = NULL;
1671                 INIT_LIST_HEAD(&urb->urb_list);
1672                 atomic_dec(&urb->use_count);
1673                 /*
1674                  * Order the write of urb->use_count above before the read
1675                  * of urb->reject below.  Pairs with the memory barriers in
1676                  * usb_kill_urb() and usb_poison_urb().
1677                  */
1678                 smp_mb__after_atomic();
1679
1680                 atomic_dec(&urb->dev->urbnum);
1681                 if (atomic_read(&urb->reject))
1682                         wake_up(&usb_kill_urb_queue);
1683                 usb_put_urb(urb);
1684         }
1685         return status;
1686 }
1687
1688 /*-------------------------------------------------------------------------*/
1689
1690 /* this makes the hcd giveback() the urb more quickly, by kicking it
1691  * off hardware queues (which may take a while) and returning it as
1692  * soon as practical.  we've already set up the urb's return status,
1693  * but we can't know if the callback completed already.
1694  */
1695 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1696 {
1697         int             value;
1698
1699         if (is_root_hub(urb->dev))
1700                 value = usb_rh_urb_dequeue(hcd, urb, status);
1701         else {
1702
1703                 /* The only reason an HCD might fail this call is if
1704                  * it has not yet fully queued the urb to begin with.
1705                  * Such failures should be harmless. */
1706                 value = hcd->driver->urb_dequeue(hcd, urb, status);
1707         }
1708         return value;
1709 }
1710
1711 /*
1712  * called in any context
1713  *
1714  * caller guarantees urb won't be recycled till both unlink()
1715  * and the urb's completion function return
1716  */
1717 int usb_hcd_unlink_urb (struct urb *urb, int status)
1718 {
1719         struct usb_hcd          *hcd;
1720         struct usb_device       *udev = urb->dev;
1721         int                     retval = -EIDRM;
1722         unsigned long           flags;
1723
1724         /* Prevent the device and bus from going away while
1725          * the unlink is carried out.  If they are already gone
1726          * then urb->use_count must be 0, since disconnected
1727          * devices can't have any active URBs.
1728          */
1729         spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1730         if (atomic_read(&urb->use_count) > 0) {
1731                 retval = 0;
1732                 usb_get_dev(udev);
1733         }
1734         spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1735         if (retval == 0) {
1736                 hcd = bus_to_hcd(urb->dev->bus);
1737                 retval = unlink1(hcd, urb, status);
1738                 if (retval == 0)
1739                         retval = -EINPROGRESS;
1740                 else if (retval != -EIDRM && retval != -EBUSY)
1741                         dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1742                                         urb, retval);
1743                 usb_put_dev(udev);
1744         }
1745         return retval;
1746 }
1747
1748 /*-------------------------------------------------------------------------*/
1749
1750 static void __usb_hcd_giveback_urb(struct urb *urb)
1751 {
1752         struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1753         struct usb_anchor *anchor = urb->anchor;
1754         int status = urb->unlinked;
1755         unsigned long flags;
1756
1757         urb->hcpriv = NULL;
1758         if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1759             urb->actual_length < urb->transfer_buffer_length &&
1760             !status))
1761                 status = -EREMOTEIO;
1762
1763         unmap_urb_for_dma(hcd, urb);
1764         usbmon_urb_complete(&hcd->self, urb, status);
1765         usb_anchor_suspend_wakeups(anchor);
1766         usb_unanchor_urb(urb);
1767         if (likely(status == 0))
1768                 usb_led_activity(USB_LED_EVENT_HOST);
1769
1770         /* pass ownership to the completion handler */
1771         urb->status = status;
1772
1773         /*
1774          * We disable local IRQs here avoid possible deadlock because
1775          * drivers may call spin_lock() to hold lock which might be
1776          * acquired in one hard interrupt handler.
1777          *
1778          * The local_irq_save()/local_irq_restore() around complete()
1779          * will be removed if current USB drivers have been cleaned up
1780          * and no one may trigger the above deadlock situation when
1781          * running complete() in tasklet.
1782          */
1783         local_irq_save(flags);
1784         urb->complete(urb);
1785         local_irq_restore(flags);
1786
1787         usb_anchor_resume_wakeups(anchor);
1788         atomic_dec(&urb->use_count);
1789         /*
1790          * Order the write of urb->use_count above before the read
1791          * of urb->reject below.  Pairs with the memory barriers in
1792          * usb_kill_urb() and usb_poison_urb().
1793          */
1794         smp_mb__after_atomic();
1795
1796         if (unlikely(atomic_read(&urb->reject)))
1797                 wake_up(&usb_kill_urb_queue);
1798         usb_put_urb(urb);
1799 }
1800
1801 static void usb_giveback_urb_bh(unsigned long param)
1802 {
1803         struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1804         struct list_head local_list;
1805
1806         spin_lock_irq(&bh->lock);
1807         bh->running = true;
1808         list_replace_init(&bh->head, &local_list);
1809         spin_unlock_irq(&bh->lock);
1810
1811         while (!list_empty(&local_list)) {
1812                 struct urb *urb;
1813
1814                 urb = list_entry(local_list.next, struct urb, urb_list);
1815                 list_del_init(&urb->urb_list);
1816                 bh->completing_ep = urb->ep;
1817                 __usb_hcd_giveback_urb(urb);
1818                 bh->completing_ep = NULL;
1819         }
1820
1821         /*
1822          * giveback new URBs next time to prevent this function
1823          * from not exiting for a long time.
1824          */
1825         spin_lock_irq(&bh->lock);
1826         if (!list_empty(&bh->head)) {
1827                 if (bh->high_prio)
1828                         tasklet_hi_schedule(&bh->bh);
1829                 else
1830                         tasklet_schedule(&bh->bh);
1831         }
1832         bh->running = false;
1833         spin_unlock_irq(&bh->lock);
1834 }
1835
1836 /**
1837  * usb_hcd_giveback_urb - return URB from HCD to device driver
1838  * @hcd: host controller returning the URB
1839  * @urb: urb being returned to the USB device driver.
1840  * @status: completion status code for the URB.
1841  * Context: in_interrupt()
1842  *
1843  * This hands the URB from HCD to its USB device driver, using its
1844  * completion function.  The HCD has freed all per-urb resources
1845  * (and is done using urb->hcpriv).  It also released all HCD locks;
1846  * the device driver won't cause problems if it frees, modifies,
1847  * or resubmits this URB.
1848  *
1849  * If @urb was unlinked, the value of @status will be overridden by
1850  * @urb->unlinked.  Erroneous short transfers are detected in case
1851  * the HCD hasn't checked for them.
1852  */
1853 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1854 {
1855         struct giveback_urb_bh *bh;
1856         bool running;
1857
1858         /* pass status to tasklet via unlinked */
1859         if (likely(!urb->unlinked))
1860                 urb->unlinked = status;
1861
1862         if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1863                 __usb_hcd_giveback_urb(urb);
1864                 return;
1865         }
1866
1867         if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe))
1868                 bh = &hcd->high_prio_bh;
1869         else
1870                 bh = &hcd->low_prio_bh;
1871
1872         spin_lock(&bh->lock);
1873         list_add_tail(&urb->urb_list, &bh->head);
1874         running = bh->running;
1875         spin_unlock(&bh->lock);
1876
1877         if (running)
1878                 ;
1879         else if (bh->high_prio)
1880                 tasklet_hi_schedule(&bh->bh);
1881         else
1882                 tasklet_schedule(&bh->bh);
1883 }
1884 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1885
1886 /*-------------------------------------------------------------------------*/
1887
1888 /* Cancel all URBs pending on this endpoint and wait for the endpoint's
1889  * queue to drain completely.  The caller must first insure that no more
1890  * URBs can be submitted for this endpoint.
1891  */
1892 void usb_hcd_flush_endpoint(struct usb_device *udev,
1893                 struct usb_host_endpoint *ep)
1894 {
1895         struct usb_hcd          *hcd;
1896         struct urb              *urb;
1897
1898         if (!ep)
1899                 return;
1900         might_sleep();
1901         hcd = bus_to_hcd(udev->bus);
1902
1903         /* No more submits can occur */
1904         spin_lock_irq(&hcd_urb_list_lock);
1905 rescan:
1906         list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1907                 int     is_in;
1908
1909                 if (urb->unlinked)
1910                         continue;
1911                 usb_get_urb (urb);
1912                 is_in = usb_urb_dir_in(urb);
1913                 spin_unlock(&hcd_urb_list_lock);
1914
1915                 /* kick hcd */
1916                 unlink1(hcd, urb, -ESHUTDOWN);
1917                 dev_dbg (hcd->self.controller,
1918                         "shutdown urb %pK ep%d%s%s\n",
1919                         urb, usb_endpoint_num(&ep->desc),
1920                         is_in ? "in" : "out",
1921                         ({      char *s;
1922
1923                                  switch (usb_endpoint_type(&ep->desc)) {
1924                                  case USB_ENDPOINT_XFER_CONTROL:
1925                                         s = ""; break;
1926                                  case USB_ENDPOINT_XFER_BULK:
1927                                         s = "-bulk"; break;
1928                                  case USB_ENDPOINT_XFER_INT:
1929                                         s = "-intr"; break;
1930                                  default:
1931                                         s = "-iso"; break;
1932                                 };
1933                                 s;
1934                         }));
1935                 usb_put_urb (urb);
1936
1937                 /* list contents may have changed */
1938                 spin_lock(&hcd_urb_list_lock);
1939                 goto rescan;
1940         }
1941         spin_unlock_irq(&hcd_urb_list_lock);
1942
1943         /* Wait until the endpoint queue is completely empty */
1944         while (!list_empty (&ep->urb_list)) {
1945                 spin_lock_irq(&hcd_urb_list_lock);
1946
1947                 /* The list may have changed while we acquired the spinlock */
1948                 urb = NULL;
1949                 if (!list_empty (&ep->urb_list)) {
1950                         urb = list_entry (ep->urb_list.prev, struct urb,
1951                                         urb_list);
1952                         usb_get_urb (urb);
1953                 }
1954                 spin_unlock_irq(&hcd_urb_list_lock);
1955
1956                 if (urb) {
1957                         usb_kill_urb (urb);
1958                         usb_put_urb (urb);
1959                 }
1960         }
1961 }
1962
1963 /**
1964  * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1965  *                              the bus bandwidth
1966  * @udev: target &usb_device
1967  * @new_config: new configuration to install
1968  * @cur_alt: the current alternate interface setting
1969  * @new_alt: alternate interface setting that is being installed
1970  *
1971  * To change configurations, pass in the new configuration in new_config,
1972  * and pass NULL for cur_alt and new_alt.
1973  *
1974  * To reset a device's configuration (put the device in the ADDRESSED state),
1975  * pass in NULL for new_config, cur_alt, and new_alt.
1976  *
1977  * To change alternate interface settings, pass in NULL for new_config,
1978  * pass in the current alternate interface setting in cur_alt,
1979  * and pass in the new alternate interface setting in new_alt.
1980  *
1981  * Return: An error if the requested bandwidth change exceeds the
1982  * bus bandwidth or host controller internal resources.
1983  */
1984 int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1985                 struct usb_host_config *new_config,
1986                 struct usb_host_interface *cur_alt,
1987                 struct usb_host_interface *new_alt)
1988 {
1989         int num_intfs, i, j;
1990         struct usb_host_interface *alt = NULL;
1991         int ret = 0;
1992         struct usb_hcd *hcd;
1993         struct usb_host_endpoint *ep;
1994
1995         hcd = bus_to_hcd(udev->bus);
1996         if (!hcd->driver->check_bandwidth)
1997                 return 0;
1998
1999         /* Configuration is being removed - set configuration 0 */
2000         if (!new_config && !cur_alt) {
2001                 for (i = 1; i < 16; ++i) {
2002                         ep = udev->ep_out[i];
2003                         if (ep)
2004                                 hcd->driver->drop_endpoint(hcd, udev, ep);
2005                         ep = udev->ep_in[i];
2006                         if (ep)
2007                                 hcd->driver->drop_endpoint(hcd, udev, ep);
2008                 }
2009                 hcd->driver->check_bandwidth(hcd, udev);
2010                 return 0;
2011         }
2012         /* Check if the HCD says there's enough bandwidth.  Enable all endpoints
2013          * each interface's alt setting 0 and ask the HCD to check the bandwidth
2014          * of the bus.  There will always be bandwidth for endpoint 0, so it's
2015          * ok to exclude it.
2016          */
2017         if (new_config) {
2018                 num_intfs = new_config->desc.bNumInterfaces;
2019                 /* Remove endpoints (except endpoint 0, which is always on the
2020                  * schedule) from the old config from the schedule
2021                  */
2022                 for (i = 1; i < 16; ++i) {
2023                         ep = udev->ep_out[i];
2024                         if (ep) {
2025                                 ret = hcd->driver->drop_endpoint(hcd, udev, ep);
2026                                 if (ret < 0)
2027                                         goto reset;
2028                         }
2029                         ep = udev->ep_in[i];
2030                         if (ep) {
2031                                 ret = hcd->driver->drop_endpoint(hcd, udev, ep);
2032                                 if (ret < 0)
2033                                         goto reset;
2034                         }
2035                 }
2036                 for (i = 0; i < num_intfs; ++i) {
2037                         struct usb_host_interface *first_alt;
2038                         int iface_num;
2039
2040                         first_alt = &new_config->intf_cache[i]->altsetting[0];
2041                         iface_num = first_alt->desc.bInterfaceNumber;
2042                         /* Set up endpoints for alternate interface setting 0 */
2043                         alt = usb_find_alt_setting(new_config, iface_num, 0);
2044                         if (!alt)
2045                                 /* No alt setting 0? Pick the first setting. */
2046                                 alt = first_alt;
2047
2048                         for (j = 0; j < alt->desc.bNumEndpoints; j++) {
2049                                 ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
2050                                 if (ret < 0)
2051                                         goto reset;
2052                         }
2053                 }
2054         }
2055         if (cur_alt && new_alt) {
2056                 struct usb_interface *iface = usb_ifnum_to_if(udev,
2057                                 cur_alt->desc.bInterfaceNumber);
2058
2059                 if (!iface)
2060                         return -EINVAL;
2061                 if (iface->resetting_device) {
2062                         /*
2063                          * The USB core just reset the device, so the xHCI host
2064                          * and the device will think alt setting 0 is installed.
2065                          * However, the USB core will pass in the alternate
2066                          * setting installed before the reset as cur_alt.  Dig
2067                          * out the alternate setting 0 structure, or the first
2068                          * alternate setting if a broken device doesn't have alt
2069                          * setting 0.
2070                          */
2071                         cur_alt = usb_altnum_to_altsetting(iface, 0);
2072                         if (!cur_alt)
2073                                 cur_alt = &iface->altsetting[0];
2074                 }
2075
2076                 /* Drop all the endpoints in the current alt setting */
2077                 for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
2078                         ret = hcd->driver->drop_endpoint(hcd, udev,
2079                                         &cur_alt->endpoint[i]);
2080                         if (ret < 0)
2081                                 goto reset;
2082                 }
2083                 /* Add all the endpoints in the new alt setting */
2084                 for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
2085                         ret = hcd->driver->add_endpoint(hcd, udev,
2086                                         &new_alt->endpoint[i]);
2087                         if (ret < 0)
2088                                 goto reset;
2089                 }
2090         }
2091         ret = hcd->driver->check_bandwidth(hcd, udev);
2092 reset:
2093         if (ret < 0)
2094                 hcd->driver->reset_bandwidth(hcd, udev);
2095         return ret;
2096 }
2097
2098 /* Disables the endpoint: synchronizes with the hcd to make sure all
2099  * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
2100  * have been called previously.  Use for set_configuration, set_interface,
2101  * driver removal, physical disconnect.
2102  *
2103  * example:  a qh stored in ep->hcpriv, holding state related to endpoint
2104  * type, maxpacket size, toggle, halt status, and scheduling.
2105  */
2106 void usb_hcd_disable_endpoint(struct usb_device *udev,
2107                 struct usb_host_endpoint *ep)
2108 {
2109         struct usb_hcd          *hcd;
2110
2111         might_sleep();
2112         hcd = bus_to_hcd(udev->bus);
2113         if (hcd->driver->endpoint_disable)
2114                 hcd->driver->endpoint_disable(hcd, ep);
2115 }
2116
2117 /**
2118  * usb_hcd_reset_endpoint - reset host endpoint state
2119  * @udev: USB device.
2120  * @ep:   the endpoint to reset.
2121  *
2122  * Resets any host endpoint state such as the toggle bit, sequence
2123  * number and current window.
2124  */
2125 void usb_hcd_reset_endpoint(struct usb_device *udev,
2126                             struct usb_host_endpoint *ep)
2127 {
2128         struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2129
2130         if (hcd->driver->endpoint_reset)
2131                 hcd->driver->endpoint_reset(hcd, ep);
2132         else {
2133                 int epnum = usb_endpoint_num(&ep->desc);
2134                 int is_out = usb_endpoint_dir_out(&ep->desc);
2135                 int is_control = usb_endpoint_xfer_control(&ep->desc);
2136
2137                 usb_settoggle(udev, epnum, is_out, 0);
2138                 if (is_control)
2139                         usb_settoggle(udev, epnum, !is_out, 0);
2140         }
2141 }
2142
2143 /**
2144  * usb_alloc_streams - allocate bulk endpoint stream IDs.
2145  * @interface:          alternate setting that includes all endpoints.
2146  * @eps:                array of endpoints that need streams.
2147  * @num_eps:            number of endpoints in the array.
2148  * @num_streams:        number of streams to allocate.
2149  * @mem_flags:          flags hcd should use to allocate memory.
2150  *
2151  * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
2152  * Drivers may queue multiple transfers to different stream IDs, which may
2153  * complete in a different order than they were queued.
2154  *
2155  * Return: On success, the number of allocated streams. On failure, a negative
2156  * error code.
2157  */
2158 int usb_alloc_streams(struct usb_interface *interface,
2159                 struct usb_host_endpoint **eps, unsigned int num_eps,
2160                 unsigned int num_streams, gfp_t mem_flags)
2161 {
2162         struct usb_hcd *hcd;
2163         struct usb_device *dev;
2164         int i, ret;
2165
2166         dev = interface_to_usbdev(interface);
2167         hcd = bus_to_hcd(dev->bus);
2168         if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2169                 return -EINVAL;
2170         if (dev->speed < USB_SPEED_SUPER)
2171                 return -EINVAL;
2172         if (dev->state < USB_STATE_CONFIGURED)
2173                 return -ENODEV;
2174
2175         for (i = 0; i < num_eps; i++) {
2176                 /* Streams only apply to bulk endpoints. */
2177                 if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2178                         return -EINVAL;
2179                 /* Re-alloc is not allowed */
2180                 if (eps[i]->streams)
2181                         return -EINVAL;
2182         }
2183
2184         ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2185                         num_streams, mem_flags);
2186         if (ret < 0)
2187                 return ret;
2188
2189         for (i = 0; i < num_eps; i++)
2190                 eps[i]->streams = ret;
2191
2192         return ret;
2193 }
2194 EXPORT_SYMBOL_GPL(usb_alloc_streams);
2195
2196 /**
2197  * usb_free_streams - free bulk endpoint stream IDs.
2198  * @interface:  alternate setting that includes all endpoints.
2199  * @eps:        array of endpoints to remove streams from.
2200  * @num_eps:    number of endpoints in the array.
2201  * @mem_flags:  flags hcd should use to allocate memory.
2202  *
2203  * Reverts a group of bulk endpoints back to not using stream IDs.
2204  * Can fail if we are given bad arguments, or HCD is broken.
2205  *
2206  * Return: 0 on success. On failure, a negative error code.
2207  */
2208 int usb_free_streams(struct usb_interface *interface,
2209                 struct usb_host_endpoint **eps, unsigned int num_eps,
2210                 gfp_t mem_flags)
2211 {
2212         struct usb_hcd *hcd;
2213         struct usb_device *dev;
2214         int i, ret;
2215
2216         dev = interface_to_usbdev(interface);
2217         hcd = bus_to_hcd(dev->bus);
2218         if (dev->speed < USB_SPEED_SUPER)
2219                 return -EINVAL;
2220
2221         /* Double-free is not allowed */
2222         for (i = 0; i < num_eps; i++)
2223                 if (!eps[i] || !eps[i]->streams)
2224                         return -EINVAL;
2225
2226         ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2227         if (ret < 0)
2228                 return ret;
2229
2230         for (i = 0; i < num_eps; i++)
2231                 eps[i]->streams = 0;
2232
2233         return ret;
2234 }
2235 EXPORT_SYMBOL_GPL(usb_free_streams);
2236
2237 /* Protect against drivers that try to unlink URBs after the device
2238  * is gone, by waiting until all unlinks for @udev are finished.
2239  * Since we don't currently track URBs by device, simply wait until
2240  * nothing is running in the locked region of usb_hcd_unlink_urb().
2241  */
2242 void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2243 {
2244         spin_lock_irq(&hcd_urb_unlink_lock);
2245         spin_unlock_irq(&hcd_urb_unlink_lock);
2246 }
2247
2248 /*-------------------------------------------------------------------------*/
2249
2250 /* called in any context */
2251 int usb_hcd_get_frame_number (struct usb_device *udev)
2252 {
2253         struct usb_hcd  *hcd = bus_to_hcd(udev->bus);
2254
2255         if (!HCD_RH_RUNNING(hcd))
2256                 return -ESHUTDOWN;
2257         return hcd->driver->get_frame_number (hcd);
2258 }
2259
2260 /*-------------------------------------------------------------------------*/
2261
2262 #ifdef  CONFIG_PM
2263
2264 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2265 {
2266         struct usb_hcd  *hcd = bus_to_hcd(rhdev->bus);
2267         int             status;
2268         int             old_state = hcd->state;
2269
2270         dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2271                         (PMSG_IS_AUTO(msg) ? "auto-" : ""),
2272                         rhdev->do_remote_wakeup);
2273         if (HCD_DEAD(hcd)) {
2274                 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2275                 return 0;
2276         }
2277
2278         if (!hcd->driver->bus_suspend) {
2279                 status = -ENOENT;
2280         } else {
2281                 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2282                 hcd->state = HC_STATE_QUIESCING;
2283                 status = hcd->driver->bus_suspend(hcd);
2284         }
2285         if (status == 0) {
2286                 usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2287                 hcd->state = HC_STATE_SUSPENDED;
2288
2289                 if (!PMSG_IS_AUTO(msg))
2290                         usb_phy_roothub_suspend(hcd->self.sysdev,
2291                                                 hcd->phy_roothub);
2292
2293                 /* Did we race with a root-hub wakeup event? */
2294                 if (rhdev->do_remote_wakeup) {
2295                         char    buffer[6];
2296
2297                         status = hcd->driver->hub_status_data(hcd, buffer);
2298                         if (status != 0) {
2299                                 dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2300                                 hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2301                                 status = -EBUSY;
2302                         }
2303                 }
2304         } else {
2305                 spin_lock_irq(&hcd_root_hub_lock);
2306                 if (!HCD_DEAD(hcd)) {
2307                         set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2308                         hcd->state = old_state;
2309                 }
2310                 spin_unlock_irq(&hcd_root_hub_lock);
2311                 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2312                                 "suspend", status);
2313         }
2314         return status;
2315 }
2316
2317 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2318 {
2319         struct usb_hcd  *hcd = bus_to_hcd(rhdev->bus);
2320         int             status;
2321         int             old_state = hcd->state;
2322
2323         dev_dbg(&rhdev->dev, "usb %sresume\n",
2324                         (PMSG_IS_AUTO(msg) ? "auto-" : ""));
2325         if (HCD_DEAD(hcd)) {
2326                 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2327                 return 0;
2328         }
2329
2330         if (!PMSG_IS_AUTO(msg)) {
2331                 status = usb_phy_roothub_resume(hcd->self.sysdev,
2332                                                 hcd->phy_roothub);
2333                 if (status)
2334                         return status;
2335         }
2336
2337         if (!hcd->driver->bus_resume)
2338                 return -ENOENT;
2339         if (HCD_RH_RUNNING(hcd))
2340                 return 0;
2341
2342         hcd->state = HC_STATE_RESUMING;
2343         status = hcd->driver->bus_resume(hcd);
2344         clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2345         if (status == 0) {
2346                 struct usb_device *udev;
2347                 int port1;
2348
2349                 spin_lock_irq(&hcd_root_hub_lock);
2350                 if (!HCD_DEAD(hcd)) {
2351                         usb_set_device_state(rhdev, rhdev->actconfig
2352                                         ? USB_STATE_CONFIGURED
2353                                         : USB_STATE_ADDRESS);
2354                         set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2355                         hcd->state = HC_STATE_RUNNING;
2356                 }
2357                 spin_unlock_irq(&hcd_root_hub_lock);
2358
2359                 /*
2360                  * Check whether any of the enabled ports on the root hub are
2361                  * unsuspended.  If they are then a TRSMRCY delay is needed
2362                  * (this is what the USB-2 spec calls a "global resume").
2363                  * Otherwise we can skip the delay.
2364                  */
2365                 usb_hub_for_each_child(rhdev, port1, udev) {
2366                         if (udev->state != USB_STATE_NOTATTACHED &&
2367                                         !udev->port_is_suspended) {
2368                                 usleep_range(10000, 11000);     /* TRSMRCY */
2369                                 break;
2370                         }
2371                 }
2372         } else {
2373                 hcd->state = old_state;
2374                 usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2375                 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2376                                 "resume", status);
2377                 if (status != -ESHUTDOWN)
2378                         usb_hc_died(hcd);
2379         }
2380         return status;
2381 }
2382
2383 /* Workqueue routine for root-hub remote wakeup */
2384 static void hcd_resume_work(struct work_struct *work)
2385 {
2386         struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2387         struct usb_device *udev = hcd->self.root_hub;
2388
2389         usb_remote_wakeup(udev);
2390 }
2391
2392 /**
2393  * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2394  * @hcd: host controller for this root hub
2395  *
2396  * The USB host controller calls this function when its root hub is
2397  * suspended (with the remote wakeup feature enabled) and a remote
2398  * wakeup request is received.  The routine submits a workqueue request
2399  * to resume the root hub (that is, manage its downstream ports again).
2400  */
2401 void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2402 {
2403         unsigned long flags;
2404
2405         spin_lock_irqsave (&hcd_root_hub_lock, flags);
2406         if (hcd->rh_registered) {
2407                 pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2408                 set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2409                 queue_work(pm_wq, &hcd->wakeup_work);
2410         }
2411         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2412 }
2413 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2414
2415 #endif  /* CONFIG_PM */
2416
2417 /*-------------------------------------------------------------------------*/
2418
2419 #ifdef  CONFIG_USB_OTG
2420
2421 /**
2422  * usb_bus_start_enum - start immediate enumeration (for OTG)
2423  * @bus: the bus (must use hcd framework)
2424  * @port_num: 1-based number of port; usually bus->otg_port
2425  * Context: in_interrupt()
2426  *
2427  * Starts enumeration, with an immediate reset followed later by
2428  * hub_wq identifying and possibly configuring the device.
2429  * This is needed by OTG controller drivers, where it helps meet
2430  * HNP protocol timing requirements for starting a port reset.
2431  *
2432  * Return: 0 if successful.
2433  */
2434 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2435 {
2436         struct usb_hcd          *hcd;
2437         int                     status = -EOPNOTSUPP;
2438
2439         /* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2440          * boards with root hubs hooked up to internal devices (instead of
2441          * just the OTG port) may need more attention to resetting...
2442          */
2443         hcd = bus_to_hcd(bus);
2444         if (port_num && hcd->driver->start_port_reset)
2445                 status = hcd->driver->start_port_reset(hcd, port_num);
2446
2447         /* allocate hub_wq shortly after (first) root port reset finishes;
2448          * it may issue others, until at least 50 msecs have passed.
2449          */
2450         if (status == 0)
2451                 mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2452         return status;
2453 }
2454 EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2455
2456 #endif
2457
2458 /*-------------------------------------------------------------------------*/
2459
2460 /**
2461  * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2462  * @irq: the IRQ being raised
2463  * @__hcd: pointer to the HCD whose IRQ is being signaled
2464  *
2465  * If the controller isn't HALTed, calls the driver's irq handler.
2466  * Checks whether the controller is now dead.
2467  *
2468  * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2469  */
2470 irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2471 {
2472         struct usb_hcd          *hcd = __hcd;
2473         irqreturn_t             rc;
2474
2475         if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2476                 rc = IRQ_NONE;
2477         else if (hcd->driver->irq(hcd) == IRQ_NONE)
2478                 rc = IRQ_NONE;
2479         else
2480                 rc = IRQ_HANDLED;
2481
2482         return rc;
2483 }
2484 EXPORT_SYMBOL_GPL(usb_hcd_irq);
2485
2486 /*-------------------------------------------------------------------------*/
2487
2488 /**
2489  * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2490  * @hcd: pointer to the HCD representing the controller
2491  *
2492  * This is called by bus glue to report a USB host controller that died
2493  * while operations may still have been pending.  It's called automatically
2494  * by the PCI glue, so only glue for non-PCI busses should need to call it.
2495  *
2496  * Only call this function with the primary HCD.
2497  */
2498 void usb_hc_died (struct usb_hcd *hcd)
2499 {
2500         unsigned long flags;
2501
2502         dev_err (hcd->self.controller, "HC died; cleaning up\n");
2503
2504         spin_lock_irqsave (&hcd_root_hub_lock, flags);
2505         clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2506         set_bit(HCD_FLAG_DEAD, &hcd->flags);
2507         if (hcd->rh_registered) {
2508                 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2509
2510                 /* make hub_wq clean up old urbs and devices */
2511                 usb_set_device_state (hcd->self.root_hub,
2512                                 USB_STATE_NOTATTACHED);
2513                 usb_kick_hub_wq(hcd->self.root_hub);
2514         }
2515         if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2516                 hcd = hcd->shared_hcd;
2517                 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2518                 set_bit(HCD_FLAG_DEAD, &hcd->flags);
2519                 if (hcd->rh_registered) {
2520                         clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2521
2522                         /* make hub_wq clean up old urbs and devices */
2523                         usb_set_device_state(hcd->self.root_hub,
2524                                         USB_STATE_NOTATTACHED);
2525                         usb_kick_hub_wq(hcd->self.root_hub);
2526                 }
2527         }
2528         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2529         /* Make sure that the other roothub is also deallocated. */
2530 }
2531 EXPORT_SYMBOL_GPL (usb_hc_died);
2532
2533 /*-------------------------------------------------------------------------*/
2534
2535 static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2536 {
2537
2538         spin_lock_init(&bh->lock);
2539         INIT_LIST_HEAD(&bh->head);
2540         tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2541 }
2542
2543 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2544                 struct device *sysdev, struct device *dev, const char *bus_name,
2545                 struct usb_hcd *primary_hcd)
2546 {
2547         struct usb_hcd *hcd;
2548
2549         hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2550         if (!hcd)
2551                 return NULL;
2552         if (primary_hcd == NULL) {
2553                 hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2554                                 GFP_KERNEL);
2555                 if (!hcd->address0_mutex) {
2556                         kfree(hcd);
2557                         dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2558                         return NULL;
2559                 }
2560                 mutex_init(hcd->address0_mutex);
2561                 hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2562                                 GFP_KERNEL);
2563                 if (!hcd->bandwidth_mutex) {
2564                         kfree(hcd->address0_mutex);
2565                         kfree(hcd);
2566                         dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2567                         return NULL;
2568                 }
2569                 mutex_init(hcd->bandwidth_mutex);
2570                 dev_set_drvdata(dev, hcd);
2571         } else {
2572                 mutex_lock(&usb_port_peer_mutex);
2573                 hcd->address0_mutex = primary_hcd->address0_mutex;
2574                 hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2575                 hcd->primary_hcd = primary_hcd;
2576                 primary_hcd->primary_hcd = primary_hcd;
2577                 hcd->shared_hcd = primary_hcd;
2578                 primary_hcd->shared_hcd = hcd;
2579                 mutex_unlock(&usb_port_peer_mutex);
2580         }
2581
2582         kref_init(&hcd->kref);
2583
2584         usb_bus_init(&hcd->self);
2585         hcd->self.controller = dev;
2586         hcd->self.sysdev = sysdev;
2587         hcd->self.bus_name = bus_name;
2588         hcd->self.uses_dma = (sysdev->dma_mask != NULL);
2589
2590         timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2591 #ifdef CONFIG_PM
2592         INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2593 #endif
2594
2595         hcd->driver = driver;
2596         hcd->speed = driver->flags & HCD_MASK;
2597         hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2598                         "USB Host Controller";
2599         return hcd;
2600 }
2601 EXPORT_SYMBOL_GPL(__usb_create_hcd);
2602
2603 /**
2604  * usb_create_shared_hcd - create and initialize an HCD structure
2605  * @driver: HC driver that will use this hcd
2606  * @dev: device for this HC, stored in hcd->self.controller
2607  * @bus_name: value to store in hcd->self.bus_name
2608  * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2609  *              PCI device.  Only allocate certain resources for the primary HCD
2610  * Context: !in_interrupt()
2611  *
2612  * Allocate a struct usb_hcd, with extra space at the end for the
2613  * HC driver's private data.  Initialize the generic members of the
2614  * hcd structure.
2615  *
2616  * Return: On success, a pointer to the created and initialized HCD structure.
2617  * On failure (e.g. if memory is unavailable), %NULL.
2618  */
2619 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2620                 struct device *dev, const char *bus_name,
2621                 struct usb_hcd *primary_hcd)
2622 {
2623         return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2624 }
2625 EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2626
2627 /**
2628  * usb_create_hcd - create and initialize an HCD structure
2629  * @driver: HC driver that will use this hcd
2630  * @dev: device for this HC, stored in hcd->self.controller
2631  * @bus_name: value to store in hcd->self.bus_name
2632  * Context: !in_interrupt()
2633  *
2634  * Allocate a struct usb_hcd, with extra space at the end for the
2635  * HC driver's private data.  Initialize the generic members of the
2636  * hcd structure.
2637  *
2638  * Return: On success, a pointer to the created and initialized HCD
2639  * structure. On failure (e.g. if memory is unavailable), %NULL.
2640  */
2641 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2642                 struct device *dev, const char *bus_name)
2643 {
2644         return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2645 }
2646 EXPORT_SYMBOL_GPL(usb_create_hcd);
2647
2648 /*
2649  * Roothubs that share one PCI device must also share the bandwidth mutex.
2650  * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2651  * deallocated.
2652  *
2653  * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2654  * freed.  When hcd_release() is called for either hcd in a peer set,
2655  * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2656  */
2657 static void hcd_release(struct kref *kref)
2658 {
2659         struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2660
2661         mutex_lock(&usb_port_peer_mutex);
2662         if (hcd->shared_hcd) {
2663                 struct usb_hcd *peer = hcd->shared_hcd;
2664
2665                 peer->shared_hcd = NULL;
2666                 peer->primary_hcd = NULL;
2667         } else {
2668                 kfree(hcd->address0_mutex);
2669                 kfree(hcd->bandwidth_mutex);
2670         }
2671         mutex_unlock(&usb_port_peer_mutex);
2672         kfree(hcd);
2673 }
2674
2675 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2676 {
2677         if (hcd)
2678                 kref_get (&hcd->kref);
2679         return hcd;
2680 }
2681 EXPORT_SYMBOL_GPL(usb_get_hcd);
2682
2683 void usb_put_hcd (struct usb_hcd *hcd)
2684 {
2685         if (hcd)
2686                 kref_put (&hcd->kref, hcd_release);
2687 }
2688 EXPORT_SYMBOL_GPL(usb_put_hcd);
2689
2690 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2691 {
2692         if (!hcd->primary_hcd)
2693                 return 1;
2694         return hcd == hcd->primary_hcd;
2695 }
2696 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2697
2698 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2699 {
2700         if (!hcd->driver->find_raw_port_number)
2701                 return port1;
2702
2703         return hcd->driver->find_raw_port_number(hcd, port1);
2704 }
2705
2706 static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2707                 unsigned int irqnum, unsigned long irqflags)
2708 {
2709         int retval;
2710
2711         if (hcd->driver->irq) {
2712
2713                 snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2714                                 hcd->driver->description, hcd->self.busnum);
2715                 retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2716                                 hcd->irq_descr, hcd);
2717                 if (retval != 0) {
2718                         dev_err(hcd->self.controller,
2719                                         "request interrupt %d failed\n",
2720                                         irqnum);
2721                         return retval;
2722                 }
2723                 hcd->irq = irqnum;
2724                 dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2725                                 (hcd->driver->flags & HCD_MEMORY) ?
2726                                         "io mem" : "io base",
2727                                         (unsigned long long)hcd->rsrc_start);
2728         } else {
2729                 hcd->irq = 0;
2730                 if (hcd->rsrc_start)
2731                         dev_info(hcd->self.controller, "%s 0x%08llx\n",
2732                                         (hcd->driver->flags & HCD_MEMORY) ?
2733                                         "io mem" : "io base",
2734                                         (unsigned long long)hcd->rsrc_start);
2735         }
2736         return 0;
2737 }
2738
2739 /*
2740  * Before we free this root hub, flush in-flight peering attempts
2741  * and disable peer lookups
2742  */
2743 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2744 {
2745         struct usb_device *rhdev;
2746
2747         mutex_lock(&usb_port_peer_mutex);
2748         rhdev = hcd->self.root_hub;
2749         hcd->self.root_hub = NULL;
2750         mutex_unlock(&usb_port_peer_mutex);
2751         usb_put_dev(rhdev);
2752 }
2753
2754 /**
2755  * usb_add_hcd - finish generic HCD structure initialization and register
2756  * @hcd: the usb_hcd structure to initialize
2757  * @irqnum: Interrupt line to allocate
2758  * @irqflags: Interrupt type flags
2759  *
2760  * Finish the remaining parts of generic HCD initialization: allocate the
2761  * buffers of consistent memory, register the bus, request the IRQ line,
2762  * and call the driver's reset() and start() routines.
2763  */
2764 int usb_add_hcd(struct usb_hcd *hcd,
2765                 unsigned int irqnum, unsigned long irqflags)
2766 {
2767         int retval;
2768         struct usb_device *rhdev;
2769
2770         if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2771                 hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2772                 if (IS_ERR(hcd->phy_roothub))
2773                         return PTR_ERR(hcd->phy_roothub);
2774
2775                 retval = usb_phy_roothub_init(hcd->phy_roothub);
2776                 if (retval)
2777                         return retval;
2778
2779                 retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2780                 if (retval)
2781                         goto err_usb_phy_roothub_power_on;
2782         }
2783
2784         dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2785
2786         /* Keep old behaviour if authorized_default is not in [0, 1]. */
2787         if (authorized_default < 0 || authorized_default > 1) {
2788                 if (hcd->wireless)
2789                         clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2790                 else
2791                         set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2792         } else {
2793                 if (authorized_default)
2794                         set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2795                 else
2796                         clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
2797         }
2798         set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2799
2800         /* per default all interfaces are authorized */
2801         set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2802
2803         /* HC is in reset state, but accessible.  Now do the one-time init,
2804          * bottom up so that hcds can customize the root hubs before hub_wq
2805          * starts talking to them.  (Note, bus id is assigned early too.)
2806          */
2807         retval = hcd_buffer_create(hcd);
2808         if (retval != 0) {
2809                 dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2810                 goto err_create_buf;
2811         }
2812
2813         retval = usb_register_bus(&hcd->self);
2814         if (retval < 0)
2815                 goto err_register_bus;
2816
2817         rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2818         if (rhdev == NULL) {
2819                 dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2820                 retval = -ENOMEM;
2821                 goto err_allocate_root_hub;
2822         }
2823         mutex_lock(&usb_port_peer_mutex);
2824         hcd->self.root_hub = rhdev;
2825         mutex_unlock(&usb_port_peer_mutex);
2826
2827         rhdev->rx_lanes = 1;
2828         rhdev->tx_lanes = 1;
2829
2830         switch (hcd->speed) {
2831         case HCD_USB11:
2832                 rhdev->speed = USB_SPEED_FULL;
2833                 break;
2834         case HCD_USB2:
2835                 rhdev->speed = USB_SPEED_HIGH;
2836                 break;
2837         case HCD_USB25:
2838                 rhdev->speed = USB_SPEED_WIRELESS;
2839                 break;
2840         case HCD_USB3:
2841                 rhdev->speed = USB_SPEED_SUPER;
2842                 break;
2843         case HCD_USB32:
2844                 rhdev->rx_lanes = 2;
2845                 rhdev->tx_lanes = 2;
2846                 /* fall through */
2847         case HCD_USB31:
2848                 rhdev->speed = USB_SPEED_SUPER_PLUS;
2849                 break;
2850         default:
2851                 retval = -EINVAL;
2852                 goto err_set_rh_speed;
2853         }
2854
2855         /* wakeup flag init defaults to "everything works" for root hubs,
2856          * but drivers can override it in reset() if needed, along with
2857          * recording the overall controller's system wakeup capability.
2858          */
2859         device_set_wakeup_capable(&rhdev->dev, 1);
2860
2861         /* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2862          * registered.  But since the controller can die at any time,
2863          * let's initialize the flag before touching the hardware.
2864          */
2865         set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2866
2867         /* "reset" is misnamed; its role is now one-time init. the controller
2868          * should already have been reset (and boot firmware kicked off etc).
2869          */
2870         if (hcd->driver->reset) {
2871                 retval = hcd->driver->reset(hcd);
2872                 if (retval < 0) {
2873                         dev_err(hcd->self.controller, "can't setup: %d\n",
2874                                         retval);
2875                         goto err_hcd_driver_setup;
2876                 }
2877         }
2878         hcd->rh_pollable = 1;
2879
2880         /* NOTE: root hub and controller capabilities may not be the same */
2881         if (device_can_wakeup(hcd->self.controller)
2882                         && device_can_wakeup(&hcd->self.root_hub->dev))
2883                 dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2884
2885         /* initialize tasklets */
2886         init_giveback_urb_bh(&hcd->high_prio_bh);
2887         hcd->high_prio_bh.high_prio = true;
2888         init_giveback_urb_bh(&hcd->low_prio_bh);
2889
2890         /* enable irqs just before we start the controller,
2891          * if the BIOS provides legacy PCI irqs.
2892          */
2893         if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2894                 retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2895                 if (retval)
2896                         goto err_request_irq;
2897         }
2898
2899         hcd->state = HC_STATE_RUNNING;
2900         retval = hcd->driver->start(hcd);
2901         if (retval < 0) {
2902                 dev_err(hcd->self.controller, "startup error %d\n", retval);
2903                 goto err_hcd_driver_start;
2904         }
2905
2906         /* starting here, usbcore will pay attention to this root hub */
2907         retval = register_root_hub(hcd);
2908         if (retval != 0)
2909                 goto err_register_root_hub;
2910
2911         retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2912         if (retval < 0) {
2913                 printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
2914                        retval);
2915                 goto error_create_attr_group;
2916         }
2917         if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2918                 usb_hcd_poll_rh_status(hcd);
2919
2920         return retval;
2921
2922 error_create_attr_group:
2923         clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2924         if (HC_IS_RUNNING(hcd->state))
2925                 hcd->state = HC_STATE_QUIESCING;
2926         spin_lock_irq(&hcd_root_hub_lock);
2927         hcd->rh_registered = 0;
2928         spin_unlock_irq(&hcd_root_hub_lock);
2929
2930 #ifdef CONFIG_PM
2931         cancel_work_sync(&hcd->wakeup_work);
2932 #endif
2933         mutex_lock(&usb_bus_idr_lock);
2934         usb_disconnect(&rhdev);         /* Sets rhdev to NULL */
2935         mutex_unlock(&usb_bus_idr_lock);
2936 err_register_root_hub:
2937         hcd->rh_pollable = 0;
2938         clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2939         del_timer_sync(&hcd->rh_timer);
2940         hcd->driver->stop(hcd);
2941         hcd->state = HC_STATE_HALT;
2942         clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2943         del_timer_sync(&hcd->rh_timer);
2944 err_hcd_driver_start:
2945         if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2946                 free_irq(irqnum, hcd);
2947 err_request_irq:
2948 err_hcd_driver_setup:
2949 err_set_rh_speed:
2950         usb_put_invalidate_rhdev(hcd);
2951 err_allocate_root_hub:
2952         usb_deregister_bus(&hcd->self);
2953 err_register_bus:
2954         hcd_buffer_destroy(hcd);
2955 err_create_buf:
2956         usb_phy_roothub_power_off(hcd->phy_roothub);
2957 err_usb_phy_roothub_power_on:
2958         usb_phy_roothub_exit(hcd->phy_roothub);
2959
2960         return retval;
2961 }
2962 EXPORT_SYMBOL_GPL(usb_add_hcd);
2963
2964 /**
2965  * usb_remove_hcd - shutdown processing for generic HCDs
2966  * @hcd: the usb_hcd structure to remove
2967  * Context: !in_interrupt()
2968  *
2969  * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2970  * invoking the HCD's stop() method.
2971  */
2972 void usb_remove_hcd(struct usb_hcd *hcd)
2973 {
2974         struct usb_device *rhdev = hcd->self.root_hub;
2975
2976         dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2977
2978         usb_get_dev(rhdev);
2979         sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
2980
2981         clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2982         if (HC_IS_RUNNING (hcd->state))
2983                 hcd->state = HC_STATE_QUIESCING;
2984
2985         dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2986         spin_lock_irq (&hcd_root_hub_lock);
2987         hcd->rh_registered = 0;
2988         spin_unlock_irq (&hcd_root_hub_lock);
2989
2990 #ifdef CONFIG_PM
2991         cancel_work_sync(&hcd->wakeup_work);
2992 #endif
2993
2994         mutex_lock(&usb_bus_idr_lock);
2995         usb_disconnect(&rhdev);         /* Sets rhdev to NULL */
2996         mutex_unlock(&usb_bus_idr_lock);
2997
2998         /*
2999          * tasklet_kill() isn't needed here because:
3000          * - driver's disconnect() called from usb_disconnect() should
3001          *   make sure its URBs are completed during the disconnect()
3002          *   callback
3003          *
3004          * - it is too late to run complete() here since driver may have
3005          *   been removed already now
3006          */
3007
3008         /* Prevent any more root-hub status calls from the timer.
3009          * The HCD might still restart the timer (if a port status change
3010          * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
3011          * the hub_status_data() callback.
3012          */
3013         hcd->rh_pollable = 0;
3014         clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3015         del_timer_sync(&hcd->rh_timer);
3016
3017         hcd->driver->stop(hcd);
3018         hcd->state = HC_STATE_HALT;
3019
3020         /* In case the HCD restarted the timer, stop it again. */
3021         clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
3022         del_timer_sync(&hcd->rh_timer);
3023
3024         if (usb_hcd_is_primary_hcd(hcd)) {
3025                 if (hcd->irq > 0)
3026                         free_irq(hcd->irq, hcd);
3027         }
3028
3029         usb_deregister_bus(&hcd->self);
3030         hcd_buffer_destroy(hcd);
3031
3032         usb_phy_roothub_power_off(hcd->phy_roothub);
3033         usb_phy_roothub_exit(hcd->phy_roothub);
3034
3035         usb_put_invalidate_rhdev(hcd);
3036         hcd->flags = 0;
3037 }
3038 EXPORT_SYMBOL_GPL(usb_remove_hcd);
3039
3040 void
3041 usb_hcd_platform_shutdown(struct platform_device *dev)
3042 {
3043         struct usb_hcd *hcd = platform_get_drvdata(dev);
3044
3045         /* No need for pm_runtime_put(), we're shutting down */
3046         pm_runtime_get_sync(&dev->dev);
3047
3048         if (hcd->driver->shutdown)
3049                 hcd->driver->shutdown(hcd);
3050 }
3051 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
3052
3053 /*-------------------------------------------------------------------------*/
3054
3055 #if IS_ENABLED(CONFIG_USB_MON)
3056
3057 const struct usb_mon_operations *mon_ops;
3058
3059 /*
3060  * The registration is unlocked.
3061  * We do it this way because we do not want to lock in hot paths.
3062  *
3063  * Notice that the code is minimally error-proof. Because usbmon needs
3064  * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
3065  */
3066
3067 int usb_mon_register(const struct usb_mon_operations *ops)
3068 {
3069
3070         if (mon_ops)
3071                 return -EBUSY;
3072
3073         mon_ops = ops;
3074         mb();
3075         return 0;
3076 }
3077 EXPORT_SYMBOL_GPL (usb_mon_register);
3078
3079 void usb_mon_deregister (void)
3080 {
3081
3082         if (mon_ops == NULL) {
3083                 printk(KERN_ERR "USB: monitor was not registered\n");
3084                 return;
3085         }
3086         mon_ops = NULL;
3087         mb();
3088 }
3089 EXPORT_SYMBOL_GPL (usb_mon_deregister);
3090
3091 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */