1/*
   2 * drivers/usb/driver.c - most of the driver model stuff for usb
   3 *
   4 * (C) Copyright 2005 Greg Kroah-Hartman <gregkh@suse.de>
   5 *
   6 * based on drivers/usb/usb.c which had the following copyrights:
   7 *	(C) Copyright Linus Torvalds 1999
   8 *	(C) Copyright Johannes Erdfelt 1999-2001
   9 *	(C) Copyright Andreas Gal 1999
  10 *	(C) Copyright Gregory P. Smith 1999
  11 *	(C) Copyright Deti Fliegl 1999 (new USB architecture)
  12 *	(C) Copyright Randy Dunlap 2000
  13 *	(C) Copyright David Brownell 2000-2004
  14 *	(C) Copyright Yggdrasil Computing, Inc. 2000
  15 *		(usb_device_id matching changes by Adam J. Richter)
  16 *	(C) Copyright Greg Kroah-Hartman 2002-2003
  17 *
  18 * Released under the GPLv2 only.
  19 * SPDX-License-Identifier: GPL-2.0
  20 *
  21 * NOTE! This is not actually a driver at all, rather this is
  22 * just a collection of helper routines that implement the
  23 * matching, probing, releasing, suspending and resuming for
  24 * real drivers.
  25 *
  26 */
  27
  28#include <linux/device.h>
  29#include <linux/slab.h>
  30#include <linux/export.h>
  31#include <linux/usb.h>
  32#include <linux/usb/quirks.h>
  33#include <linux/usb/hcd.h>
  34
  35#include "usb.h"
  36
  37
  38/*
  39 * Adds a new dynamic USBdevice ID to this driver,
  40 * and cause the driver to probe for all devices again.
  41 */
  42ssize_t usb_store_new_id(struct usb_dynids *dynids,
  43			 const struct usb_device_id *id_table,
  44			 struct device_driver *driver,
  45			 const char *buf, size_t count)
  46{
  47	struct usb_dynid *dynid;
  48	u32 idVendor = 0;
  49	u32 idProduct = 0;
  50	unsigned int bInterfaceClass = 0;
  51	u32 refVendor, refProduct;
  52	int fields = 0;
  53	int retval = 0;
  54
  55	fields = sscanf(buf, "%x %x %x %x %x", &idVendor, &idProduct,
  56			&bInterfaceClass, &refVendor, &refProduct);
  57	if (fields < 2)
  58		return -EINVAL;
  59
  60	dynid = kzalloc(sizeof(*dynid), GFP_KERNEL);
  61	if (!dynid)
  62		return -ENOMEM;
  63
  64	INIT_LIST_HEAD(&dynid->node);
  65	dynid->id.idVendor = idVendor;
  66	dynid->id.idProduct = idProduct;
  67	dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE;
  68	if (fields > 2 && bInterfaceClass) {
  69		if (bInterfaceClass > 255) {
  70			retval = -EINVAL;
  71			goto fail;
  72		}
  73
  74		dynid->id.bInterfaceClass = (u8)bInterfaceClass;
  75		dynid->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
  76	}
  77
  78	if (fields > 4) {
  79		const struct usb_device_id *id = id_table;
  80
  81		if (!id) {
  82			retval = -ENODEV;
  83			goto fail;
  84		}
  85
  86		for (; id->match_flags; id++)
  87			if (id->idVendor == refVendor && id->idProduct == refProduct)
  88				break;
  89
  90		if (id->match_flags) {
  91			dynid->id.driver_info = id->driver_info;
  92		} else {
  93			retval = -ENODEV;
  94			goto fail;
  95		}
  96	}
  97
  98	spin_lock(&dynids->lock);
  99	list_add_tail(&dynid->node, &dynids->list);
 100	spin_unlock(&dynids->lock);
 101
 102	retval = driver_attach(driver);
 103
 104	if (retval)
 105		return retval;
 106	return count;
 107
 108fail:
 109	kfree(dynid);
 110	return retval;
 111}
 112EXPORT_SYMBOL_GPL(usb_store_new_id);
 113
 114ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf)
 115{
 116	struct usb_dynid *dynid;
 117	size_t count = 0;
 118
 119	list_for_each_entry(dynid, &dynids->list, node)
 120		if (dynid->id.bInterfaceClass != 0)
 121			count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x %02x\n",
 122					   dynid->id.idVendor, dynid->id.idProduct,
 123					   dynid->id.bInterfaceClass);
 124		else
 125			count += scnprintf(&buf[count], PAGE_SIZE - count, "%04x %04x\n",
 126					   dynid->id.idVendor, dynid->id.idProduct);
 127	return count;
 128}
 129EXPORT_SYMBOL_GPL(usb_show_dynids);
 130
 131static ssize_t new_id_show(struct device_driver *driver, char *buf)
 132{
 133	struct usb_driver *usb_drv = to_usb_driver(driver);
 134
 135	return usb_show_dynids(&usb_drv->dynids, buf);
 136}
 137
 138static ssize_t new_id_store(struct device_driver *driver,
 139			    const char *buf, size_t count)
 140{
 141	struct usb_driver *usb_drv = to_usb_driver(driver);
 142
 143	return usb_store_new_id(&usb_drv->dynids, usb_drv->id_table, driver, buf, count);
 144}
 145static DRIVER_ATTR_RW(new_id);
 146
 147/*
 148 * Remove a USB device ID from this driver
 149 */
 150static ssize_t remove_id_store(struct device_driver *driver, const char *buf,
 151			       size_t count)
 152{
 153	struct usb_dynid *dynid, *n;
 154	struct usb_driver *usb_driver = to_usb_driver(driver);
 155	u32 idVendor;
 156	u32 idProduct;
 157	int fields;
 158
 159	fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
 160	if (fields < 2)
 161		return -EINVAL;
 162
 163	spin_lock(&usb_driver->dynids.lock);
 164	list_for_each_entry_safe(dynid, n, &usb_driver->dynids.list, node) {
 165		struct usb_device_id *id = &dynid->id;
 166
 167		if ((id->idVendor == idVendor) &&
 168		    (id->idProduct == idProduct)) {
 169			list_del(&dynid->node);
 170			kfree(dynid);
 171			break;
 172		}
 173	}
 174	spin_unlock(&usb_driver->dynids.lock);
 175	return count;
 176}
 177
 178static ssize_t remove_id_show(struct device_driver *driver, char *buf)
 179{
 180	return new_id_show(driver, buf);
 181}
 182static DRIVER_ATTR_RW(remove_id);
 183
 184static int usb_create_newid_files(struct usb_driver *usb_drv)
 185{
 186	int error = 0;
 187
 188	if (usb_drv->no_dynamic_id)
 189		goto exit;
 190
 191	if (usb_drv->probe != NULL) {
 192		error = driver_create_file(&usb_drv->drvwrap.driver,
 193					   &driver_attr_new_id);
 194		if (error == 0) {
 195			error = driver_create_file(&usb_drv->drvwrap.driver,
 196					&driver_attr_remove_id);
 197			if (error)
 198				driver_remove_file(&usb_drv->drvwrap.driver,
 199						&driver_attr_new_id);
 200		}
 201	}
 202exit:
 203	return error;
 204}
 205
 206static void usb_remove_newid_files(struct usb_driver *usb_drv)
 207{
 208	if (usb_drv->no_dynamic_id)
 209		return;
 210
 211	if (usb_drv->probe != NULL) {
 212		driver_remove_file(&usb_drv->drvwrap.driver,
 213				&driver_attr_remove_id);
 214		driver_remove_file(&usb_drv->drvwrap.driver,
 215				   &driver_attr_new_id);
 216	}
 217}
 218
 219static void usb_free_dynids(struct usb_driver *usb_drv)
 220{
 221	struct usb_dynid *dynid, *n;
 222
 223	spin_lock(&usb_drv->dynids.lock);
 224	list_for_each_entry_safe(dynid, n, &usb_drv->dynids.list, node) {
 225		list_del(&dynid->node);
 226		kfree(dynid);
 227	}
 228	spin_unlock(&usb_drv->dynids.lock);
 229}
 230
 231static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *intf,
 232							struct usb_driver *drv)
 233{
 234	struct usb_dynid *dynid;
 235
 236	spin_lock(&drv->dynids.lock);
 237	list_for_each_entry(dynid, &drv->dynids.list, node) {
 238		if (usb_match_one_id(intf, &dynid->id)) {
 239			spin_unlock(&drv->dynids.lock);
 240			return &dynid->id;
 241		}
 242	}
 243	spin_unlock(&drv->dynids.lock);
 244	return NULL;
 245}
 246
 247
 248/* called from driver core with dev locked */
 249static int usb_probe_device(struct device *dev)
 250{
 251	struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
 252	struct usb_device *udev = to_usb_device(dev);
 253	int error = 0;
 254
 255	dev_dbg(dev, "%s\n", __func__);
 256
 257	/* TODO: Add real matching code */
 258
 259	/* The device should always appear to be in use
 260	 * unless the driver supports autosuspend.
 261	 */
 262	if (!udriver->supports_autosuspend)
 263		error = usb_autoresume_device(udev);
 264
 265	if (!error)
 266		error = udriver->probe(udev);
 267	return error;
 268}
 269
 270/* called from driver core with dev locked */
 271static int usb_unbind_device(struct device *dev)
 272{
 273	struct usb_device *udev = to_usb_device(dev);
 274	struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
 275
 276	udriver->disconnect(udev);
 277	if (!udriver->supports_autosuspend)
 278		usb_autosuspend_device(udev);
 279	return 0;
 280}
 281
 282/* called from driver core with dev locked */
 283static int usb_probe_interface(struct device *dev)
 284{
 285	struct usb_driver *driver = to_usb_driver(dev->driver);
 286	struct usb_interface *intf = to_usb_interface(dev);
 287	struct usb_device *udev = interface_to_usbdev(intf);
 288	const struct usb_device_id *id;
 289	int error = -ENODEV;
 290	int lpm_disable_error = -ENODEV;
 291
 292	dev_dbg(dev, "%s\n", __func__);
 293
 294	intf->needs_binding = 0;
 295
 296	if (usb_device_is_owned(udev))
 297		return error;
 298
 299	if (udev->authorized == 0) {
 300		dev_err(&intf->dev, "Device is not authorized for usage\n");
 301		return error;
 302	} else if (intf->authorized == 0) {
 303		dev_err(&intf->dev, "Interface %d is not authorized for usage\n",
 304				intf->altsetting->desc.bInterfaceNumber);
 305		return error;
 306	}
 307
 308	id = usb_match_dynamic_id(intf, driver);
 309	if (!id)
 310		id = usb_match_id(intf, driver->id_table);
 311	if (!id)
 312		return error;
 313
 314	dev_dbg(dev, "%s - got id\n", __func__);
 315
 316	error = usb_autoresume_device(udev);
 317	if (error)
 318		return error;
 319
 320	intf->condition = USB_INTERFACE_BINDING;
 321
 322	/* Probed interfaces are initially active.  They are
 323	 * runtime-PM-enabled only if the driver has autosuspend support.
 324	 * They are sensitive to their children's power states.
 325	 */
 326	pm_runtime_set_active(dev);
 327	pm_suspend_ignore_children(dev, false);
 328	if (driver->supports_autosuspend)
 329		pm_runtime_enable(dev);
 330
 331	/* If the new driver doesn't allow hub-initiated LPM, and we can't
 332	 * disable hub-initiated LPM, then fail the probe.
 333	 *
 334	 * Otherwise, leaving LPM enabled should be harmless, because the
 335	 * endpoint intervals should remain the same, and the U1/U2 timeouts
 336	 * should remain the same.
 337	 *
 338	 * If we need to install alt setting 0 before probe, or another alt
 339	 * setting during probe, that should also be fine.  usb_set_interface()
 340	 * will attempt to disable LPM, and fail if it can't disable it.
 341	 */
 342	if (driver->disable_hub_initiated_lpm) {
 343		lpm_disable_error = usb_unlocked_disable_lpm(udev);
 344		if (lpm_disable_error) {
 345			dev_err(&intf->dev, "%s Failed to disable LPM for driver %s\n.",
 346					__func__, driver->name);
 347			error = lpm_disable_error;
 348			goto err;
 349		}
 350	}
 351
 352	/* Carry out a deferred switch to altsetting 0 */
 353	if (intf->needs_altsetting0) {
 354		error = usb_set_interface(udev, intf->altsetting[0].
 355				desc.bInterfaceNumber, 0);
 356		if (error < 0)
 357			goto err;
 358		intf->needs_altsetting0 = 0;
 359	}
 360
 361	error = driver->probe(intf, id);
 362	if (error)
 363		goto err;
 364
 365	intf->condition = USB_INTERFACE_BOUND;
 366
 367	/* If the LPM disable succeeded, balance the ref counts. */
 368	if (!lpm_disable_error)
 369		usb_unlocked_enable_lpm(udev);
 370
 371	usb_autosuspend_device(udev);
 372	return error;
 373
 374 err:
 375	usb_set_intfdata(intf, NULL);
 376	intf->needs_remote_wakeup = 0;
 377	intf->condition = USB_INTERFACE_UNBOUND;
 378
 379	/* If the LPM disable succeeded, balance the ref counts. */
 380	if (!lpm_disable_error)
 381		usb_unlocked_enable_lpm(udev);
 382
 383	/* Unbound interfaces are always runtime-PM-disabled and -suspended */
 384	if (driver->supports_autosuspend)
 385		pm_runtime_disable(dev);
 386	pm_runtime_set_suspended(dev);
 387
 388	usb_autosuspend_device(udev);
 389	return error;
 390}
 391
 392/* called from driver core with dev locked */
 393static int usb_unbind_interface(struct device *dev)
 394{
 395	struct usb_driver *driver = to_usb_driver(dev->driver);
 396	struct usb_interface *intf = to_usb_interface(dev);
 397	struct usb_host_endpoint *ep, **eps = NULL;
 398	struct usb_device *udev;
 399	int i, j, error, r;
 400	int lpm_disable_error = -ENODEV;
 401
 402	intf->condition = USB_INTERFACE_UNBINDING;
 403
 404	/* Autoresume for set_interface call below */
 405	udev = interface_to_usbdev(intf);
 406	error = usb_autoresume_device(udev);
 407
 408	/* If hub-initiated LPM policy may change, attempt to disable LPM until
 409	 * the driver is unbound.  If LPM isn't disabled, that's fine because it
 410	 * wouldn't be enabled unless all the bound interfaces supported
 411	 * hub-initiated LPM.
 412	 */
 413	if (driver->disable_hub_initiated_lpm)
 414		lpm_disable_error = usb_unlocked_disable_lpm(udev);
 415
 416	/*
 417	 * Terminate all URBs for this interface unless the driver
 418	 * supports "soft" unbinding and the device is still present.
 419	 */
 420	if (!driver->soft_unbind || udev->state == USB_STATE_NOTATTACHED)
 421		usb_disable_interface(udev, intf, false);
 422
 423	driver->disconnect(intf);
 424
 425	/* Free streams */
 426	for (i = 0, j = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) {
 427		ep = &intf->cur_altsetting->endpoint[i];
 428		if (ep->streams == 0)
 429			continue;
 430		if (j == 0) {
 431			eps = kmalloc_array(USB_MAXENDPOINTS, sizeof(void *),
 432				      GFP_KERNEL);
 433			if (!eps)
 434				break;
 435		}
 436		eps[j++] = ep;
 437	}
 438	if (j) {
 439		usb_free_streams(intf, eps, j, GFP_KERNEL);
 440		kfree(eps);
 441	}
 442
 443	/* Reset other interface state.
 444	 * We cannot do a Set-Interface if the device is suspended or
 445	 * if it is prepared for a system sleep (since installing a new
 446	 * altsetting means creating new endpoint device entries).
 447	 * When either of these happens, defer the Set-Interface.
 448	 */
 449	if (intf->cur_altsetting->desc.bAlternateSetting == 0) {
 450		/* Already in altsetting 0 so skip Set-Interface.
 451		 * Just re-enable it without affecting the endpoint toggles.
 452		 */
 453		usb_enable_interface(udev, intf, false);
 454	} else if (!error && !intf->dev.power.is_prepared) {
 455		r = usb_set_interface(udev, intf->altsetting[0].
 456				desc.bInterfaceNumber, 0);
 457		if (r < 0)
 458			intf->needs_altsetting0 = 1;
 459	} else {
 460		intf->needs_altsetting0 = 1;
 461	}
 462	usb_set_intfdata(intf, NULL);
 463
 464	intf->condition = USB_INTERFACE_UNBOUND;
 465	intf->needs_remote_wakeup = 0;
 466
 467	/* Attempt to re-enable USB3 LPM, if the disable succeeded. */
 468	if (!lpm_disable_error)
 469		usb_unlocked_enable_lpm(udev);
 470
 471	/* Unbound interfaces are always runtime-PM-disabled and -suspended */
 472	if (driver->supports_autosuspend)
 473		pm_runtime_disable(dev);
 474	pm_runtime_set_suspended(dev);
 475
 476	/* Undo any residual pm_autopm_get_interface_* calls */
 477	for (r = atomic_read(&intf->pm_usage_cnt); r > 0; --r)
 478		usb_autopm_put_interface_no_suspend(intf);
 479	atomic_set(&intf->pm_usage_cnt, 0);
 480
 481	if (!error)
 482		usb_autosuspend_device(udev);
 483
 484	return 0;
 485}
 486
 487/**
 488 * usb_driver_claim_interface - bind a driver to an interface
 489 * @driver: the driver to be bound
 490 * @iface: the interface to which it will be bound; must be in the
 491 *	usb device's active configuration
 492 * @priv: driver data associated with that interface
 493 *
 494 * This is used by usb device drivers that need to claim more than one
 495 * interface on a device when probing (audio and acm are current examples).
 496 * No device driver should directly modify internal usb_interface or
 497 * usb_device structure members.
 498 *
 499 * Few drivers should need to use this routine, since the most natural
 500 * way to bind to an interface is to return the private data from
 501 * the driver's probe() method.
 502 *
 503 * Callers must own the device lock, so driver probe() entries don't need
 504 * extra locking, but other call contexts may need to explicitly claim that
 505 * lock.
 506 *
 507 * Return: 0 on success.
 508 */
 509int usb_driver_claim_interface(struct usb_driver *driver,
 510				struct usb_interface *iface, void *priv)
 511{
 512	struct device *dev;
 513	struct usb_device *udev;
 514	int retval = 0;
 515	int lpm_disable_error = -ENODEV;
 516
 517	if (!iface)
 518		return -ENODEV;
 519
 520	dev = &iface->dev;
 521	if (dev->driver)
 522		return -EBUSY;
 523
 524	/* reject claim if interface is not authorized */
 525	if (!iface->authorized)
 526		return -ENODEV;
 527
 528	udev = interface_to_usbdev(iface);
 529
 530	dev->driver = &driver->drvwrap.driver;
 531	usb_set_intfdata(iface, priv);
 532	iface->needs_binding = 0;
 533
 534	iface->condition = USB_INTERFACE_BOUND;
 535
 536	/* See the comment about disabling LPM in usb_probe_interface(). */
 537	if (driver->disable_hub_initiated_lpm) {
 538		lpm_disable_error = usb_unlocked_disable_lpm(udev);
 539		if (lpm_disable_error) {
 540			dev_err(&iface->dev, "%s Failed to disable LPM for driver %s\n.",
 541					__func__, driver->name);
 542			return -ENOMEM;
 543		}
 544	}
 545
 546	/* Claimed interfaces are initially inactive (suspended) and
 547	 * runtime-PM-enabled, but only if the driver has autosuspend
 548	 * support.  Otherwise they are marked active, to prevent the
 549	 * device from being autosuspended, but left disabled.  In either
 550	 * case they are sensitive to their children's power states.
 551	 */
 552	pm_suspend_ignore_children(dev, false);
 553	if (driver->supports_autosuspend)
 554		pm_runtime_enable(dev);
 555	else
 556		pm_runtime_set_active(dev);
 557
 558	/* if interface was already added, bind now; else let
 559	 * the future device_add() bind it, bypassing probe()
 560	 */
 561	if (device_is_registered(dev))
 562		retval = device_bind_driver(dev);
 563
 564	/* Attempt to re-enable USB3 LPM, if the disable was successful. */
 565	if (!lpm_disable_error)
 566		usb_unlocked_enable_lpm(udev);
 567
 568	return retval;
 569}
 570EXPORT_SYMBOL_GPL(usb_driver_claim_interface);
 571
 572/**
 573 * usb_driver_release_interface - unbind a driver from an interface
 574 * @driver: the driver to be unbound
 575 * @iface: the interface from which it will be unbound
 576 *
 577 * This can be used by drivers to release an interface without waiting
 578 * for their disconnect() methods to be called.  In typical cases this
 579 * also causes the driver disconnect() method to be called.
 580 *
 581 * This call is synchronous, and may not be used in an interrupt context.
 582 * Callers must own the device lock, so driver disconnect() entries don't
 583 * need extra locking, but other call contexts may need to explicitly claim
 584 * that lock.
 585 */
 586void usb_driver_release_interface(struct usb_driver *driver,
 587					struct usb_interface *iface)
 588{
 589	struct device *dev = &iface->dev;
 590
 591	/* this should never happen, don't release something that's not ours */
 592	if (!dev->driver || dev->driver != &driver->drvwrap.driver)
 593		return;
 594
 595	/* don't release from within disconnect() */
 596	if (iface->condition != USB_INTERFACE_BOUND)
 597		return;
 598	iface->condition = USB_INTERFACE_UNBINDING;
 599
 600	/* Release via the driver core only if the interface
 601	 * has already been registered
 602	 */
 603	if (device_is_registered(dev)) {
 604		device_release_driver(dev);
 605	} else {
 606		device_lock(dev);
 607		usb_unbind_interface(dev);
 608		dev->driver = NULL;
 609		device_unlock(dev);
 610	}
 611}
 612EXPORT_SYMBOL_GPL(usb_driver_release_interface);
 613
 614/* returns 0 if no match, 1 if match */
 615int usb_match_device(struct usb_device *dev, const struct usb_device_id *id)
 616{
 617	if ((id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 618	    id->idVendor != le16_to_cpu(dev->descriptor.idVendor))
 619		return 0;
 620
 621	if ((id->match_flags & USB_DEVICE_ID_MATCH_PRODUCT) &&
 622	    id->idProduct != le16_to_cpu(dev->descriptor.idProduct))
 623		return 0;
 624
 625	/* No need to test id->bcdDevice_lo != 0, since 0 is never
 626	   greater than any unsigned number. */
 627	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_LO) &&
 628	    (id->bcdDevice_lo > le16_to_cpu(dev->descriptor.bcdDevice)))
 629		return 0;
 630
 631	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_HI) &&
 632	    (id->bcdDevice_hi < le16_to_cpu(dev->descriptor.bcdDevice)))
 633		return 0;
 634
 635	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_CLASS) &&
 636	    (id->bDeviceClass != dev->descriptor.bDeviceClass))
 637		return 0;
 638
 639	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_SUBCLASS) &&
 640	    (id->bDeviceSubClass != dev->descriptor.bDeviceSubClass))
 641		return 0;
 642
 643	if ((id->match_flags & USB_DEVICE_ID_MATCH_DEV_PROTOCOL) &&
 644	    (id->bDeviceProtocol != dev->descriptor.bDeviceProtocol))
 645		return 0;
 646
 647	return 1;
 648}
 649
 650/* returns 0 if no match, 1 if match */
 651int usb_match_one_id_intf(struct usb_device *dev,
 652			  struct usb_host_interface *intf,
 653			  const struct usb_device_id *id)
 654{
 655	/* The interface class, subclass, protocol and number should never be
 656	 * checked for a match if the device class is Vendor Specific,
 657	 * unless the match record specifies the Vendor ID. */
 658	if (dev->descriptor.bDeviceClass == USB_CLASS_VENDOR_SPEC &&
 659			!(id->match_flags & USB_DEVICE_ID_MATCH_VENDOR) &&
 660			(id->match_flags & (USB_DEVICE_ID_MATCH_INT_CLASS |
 661				USB_DEVICE_ID_MATCH_INT_SUBCLASS |
 662				USB_DEVICE_ID_MATCH_INT_PROTOCOL |
 663				USB_DEVICE_ID_MATCH_INT_NUMBER)))
 664		return 0;
 665
 666	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_CLASS) &&
 667	    (id->bInterfaceClass != intf->desc.bInterfaceClass))
 668		return 0;
 669
 670	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_SUBCLASS) &&
 671	    (id->bInterfaceSubClass != intf->desc.bInterfaceSubClass))
 672		return 0;
 673
 674	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_PROTOCOL) &&
 675	    (id->bInterfaceProtocol != intf->desc.bInterfaceProtocol))
 676		return 0;
 677
 678	if ((id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER) &&
 679	    (id->bInterfaceNumber != intf->desc.bInterfaceNumber))
 680		return 0;
 681
 682	return 1;
 683}
 684
 685/* returns 0 if no match, 1 if match */
 686int usb_match_one_id(struct usb_interface *interface,
 687		     const struct usb_device_id *id)
 688{
 689	struct usb_host_interface *intf;
 690	struct usb_device *dev;
 691
 692	/* proc_connectinfo in devio.c may call us with id == NULL. */
 693	if (id == NULL)
 694		return 0;
 695
 696	intf = interface->cur_altsetting;
 697	dev = interface_to_usbdev(interface);
 698
 699	if (!usb_match_device(dev, id))
 700		return 0;
 701
 702	return usb_match_one_id_intf(dev, intf, id);
 703}
 704EXPORT_SYMBOL_GPL(usb_match_one_id);
 705
 706/**
 707 * usb_match_id - find first usb_device_id matching device or interface
 708 * @interface: the interface of interest
 709 * @id: array of usb_device_id structures, terminated by zero entry
 710 *
 711 * usb_match_id searches an array of usb_device_id's and returns
 712 * the first one matching the device or interface, or null.
 713 * This is used when binding (or rebinding) a driver to an interface.
 714 * Most USB device drivers will use this indirectly, through the usb core,
 715 * but some layered driver frameworks use it directly.
 716 * These device tables are exported with MODULE_DEVICE_TABLE, through
 717 * modutils, to support the driver loading functionality of USB hotplugging.
 718 *
 719 * Return: The first matching usb_device_id, or %NULL.
 720 *
 721 * What Matches:
 722 *
 723 * The "match_flags" element in a usb_device_id controls which
 724 * members are used.  If the corresponding bit is set, the
 725 * value in the device_id must match its corresponding member
 726 * in the device or interface descriptor, or else the device_id
 727 * does not match.
 728 *
 729 * "driver_info" is normally used only by device drivers,
 730 * but you can create a wildcard "matches anything" usb_device_id
 731 * as a driver's "modules.usbmap" entry if you provide an id with
 732 * only a nonzero "driver_info" field.  If you do this, the USB device
 733 * driver's probe() routine should use additional intelligence to
 734 * decide whether to bind to the specified interface.
 735 *
 736 * What Makes Good usb_device_id Tables:
 737 *
 738 * The match algorithm is very simple, so that intelligence in
 739 * driver selection must come from smart driver id records.
 740 * Unless you have good reasons to use another selection policy,
 741 * provide match elements only in related groups, and order match
 742 * specifiers from specific to general.  Use the macros provided
 743 * for that purpose if you can.
 744 *
 745 * The most specific match specifiers use device descriptor
 746 * data.  These are commonly used with product-specific matches;
 747 * the USB_DEVICE macro lets you provide vendor and product IDs,
 748 * and you can also match against ranges of product revisions.
 749 * These are widely used for devices with application or vendor
 750 * specific bDeviceClass values.
 751 *
 752 * Matches based on device class/subclass/protocol specifications
 753 * are slightly more general; use the USB_DEVICE_INFO macro, or
 754 * its siblings.  These are used with single-function devices
 755 * where bDeviceClass doesn't specify that each interface has
 756 * its own class.
 757 *
 758 * Matches based on interface class/subclass/protocol are the
 759 * most general; they let drivers bind to any interface on a
 760 * multiple-function device.  Use the USB_INTERFACE_INFO
 761 * macro, or its siblings, to match class-per-interface style
 762 * devices (as recorded in bInterfaceClass).
 763 *
 764 * Note that an entry created by USB_INTERFACE_INFO won't match
 765 * any interface if the device class is set to Vendor-Specific.
 766 * This is deliberate; according to the USB spec the meanings of
 767 * the interface class/subclass/protocol for these devices are also
 768 * vendor-specific, and hence matching against a standard product
 769 * class wouldn't work anyway.  If you really want to use an
 770 * interface-based match for such a device, create a match record
 771 * that also specifies the vendor ID.  (Unforunately there isn't a
 772 * standard macro for creating records like this.)
 773 *
 774 * Within those groups, remember that not all combinations are
 775 * meaningful.  For example, don't give a product version range
 776 * without vendor and product IDs; or specify a protocol without
 777 * its associated class and subclass.
 778 */
 779const struct usb_device_id *usb_match_id(struct usb_interface *interface,
 780					 const struct usb_device_id *id)
 781{
 782	/* proc_connectinfo in devio.c may call us with id == NULL. */
 783	if (id == NULL)
 784		return NULL;
 785
 786	/* It is important to check that id->driver_info is nonzero,
 787	   since an entry that is all zeroes except for a nonzero
 788	   id->driver_info is the way to create an entry that
 789	   indicates that the driver want to examine every
 790	   device and interface. */
 791	for (; id->idVendor || id->idProduct || id->bDeviceClass ||
 792	       id->bInterfaceClass || id->driver_info; id++) {
 793		if (usb_match_one_id(interface, id))
 794			return id;
 795	}
 796
 797	return NULL;
 798}
 799EXPORT_SYMBOL_GPL(usb_match_id);
 800
 801static int usb_device_match(struct device *dev, struct device_driver *drv)
 802{
 803	/* devices and interfaces are handled separately */
 804	if (is_usb_device(dev)) {
 805
 806		/* interface drivers never match devices */
 807		if (!is_usb_device_driver(drv))
 808			return 0;
 809
 810		/* TODO: Add real matching code */
 811		return 1;
 812
 813	} else if (is_usb_interface(dev)) {
 814		struct usb_interface *intf;
 815		struct usb_driver *usb_drv;
 816		const struct usb_device_id *id;
 817
 818		/* device drivers never match interfaces */
 819		if (is_usb_device_driver(drv))
 820			return 0;
 821
 822		intf = to_usb_interface(dev);
 823		usb_drv = to_usb_driver(drv);
 824
 825		id = usb_match_id(intf, usb_drv->id_table);
 826		if (id)
 827			return 1;
 828
 829		id = usb_match_dynamic_id(intf, usb_drv);
 830		if (id)
 831			return 1;
 832	}
 833
 834	return 0;
 835}
 836
 837static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
 838{
 839	struct usb_device *usb_dev;
 840
 841	if (is_usb_device(dev)) {
 842		usb_dev = to_usb_device(dev);
 843	} else if (is_usb_interface(dev)) {
 844		struct usb_interface *intf = to_usb_interface(dev);
 845
 846		usb_dev = interface_to_usbdev(intf);
 847	} else {
 848		return 0;
 849	}
 850
 851	if (usb_dev->devnum < 0) {
 852		/* driver is often null here; dev_dbg() would oops */
 853		pr_debug("usb %s: already deleted?\n", dev_name(dev));
 854		return -ENODEV;
 855	}
 856	if (!usb_dev->bus) {
 857		pr_debug("usb %s: bus removed?\n", dev_name(dev));
 858		return -ENODEV;
 859	}
 860
 861	/* per-device configurations are common */
 862	if (add_uevent_var(env, "PRODUCT=%x/%x/%x",
 863			   le16_to_cpu(usb_dev->descriptor.idVendor),
 864			   le16_to_cpu(usb_dev->descriptor.idProduct),
 865			   le16_to_cpu(usb_dev->descriptor.bcdDevice)))
 866		return -ENOMEM;
 867
 868	/* class-based driver binding models */
 869	if (add_uevent_var(env, "TYPE=%d/%d/%d",
 870			   usb_dev->descriptor.bDeviceClass,
 871			   usb_dev->descriptor.bDeviceSubClass,
 872			   usb_dev->descriptor.bDeviceProtocol))
 873		return -ENOMEM;
 874
 875	return 0;
 876}
 877
 878/**
 879 * usb_register_device_driver - register a USB device (not interface) driver
 880 * @new_udriver: USB operations for the device driver
 881 * @owner: module owner of this driver.
 882 *
 883 * Registers a USB device driver with the USB core.  The list of
 884 * unattached devices will be rescanned whenever a new driver is
 885 * added, allowing the new driver to attach to any recognized devices.
 886 *
 887 * Return: A negative error code on failure and 0 on success.
 888 */
 889int usb_register_device_driver(struct usb_device_driver *new_udriver,
 890		struct module *owner)
 891{
 892	int retval = 0;
 893
 894	if (usb_disabled())
 895		return -ENODEV;
 896
 897	new_udriver->drvwrap.for_devices = 1;
 898	new_udriver->drvwrap.driver.name = new_udriver->name;
 899	new_udriver->drvwrap.driver.bus = &usb_bus_type;
 900	new_udriver->drvwrap.driver.probe = usb_probe_device;
 901	new_udriver->drvwrap.driver.remove = usb_unbind_device;
 902	new_udriver->drvwrap.driver.owner = owner;
 903
 904	retval = driver_register(&new_udriver->drvwrap.driver);
 905
 906	if (!retval)
 907		pr_info("%s: registered new device driver %s\n",
 908			usbcore_name, new_udriver->name);
 909	else
 910		printk(KERN_ERR "%s: error %d registering device "
 911			"	driver %s\n",
 912			usbcore_name, retval, new_udriver->name);
 913
 914	return retval;
 915}
 916EXPORT_SYMBOL_GPL(usb_register_device_driver);
 917
 918/**
 919 * usb_deregister_device_driver - unregister a USB device (not interface) driver
 920 * @udriver: USB operations of the device driver to unregister
 921 * Context: must be able to sleep
 922 *
 923 * Unlinks the specified driver from the internal USB driver list.
 924 */
 925void usb_deregister_device_driver(struct usb_device_driver *udriver)
 926{
 927	pr_info("%s: deregistering device driver %s\n",
 928			usbcore_name, udriver->name);
 929
 930	driver_unregister(&udriver->drvwrap.driver);
 931}
 932EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
 933
 934/**
 935 * usb_register_driver - register a USB interface driver
 936 * @new_driver: USB operations for the interface driver
 937 * @owner: module owner of this driver.
 938 * @mod_name: module name string
 939 *
 940 * Registers a USB interface driver with the USB core.  The list of
 941 * unattached interfaces will be rescanned whenever a new driver is
 942 * added, allowing the new driver to attach to any recognized interfaces.
 943 *
 944 * Return: A negative error code on failure and 0 on success.
 945 *
 946 * NOTE: if you want your driver to use the USB major number, you must call
 947 * usb_register_dev() to enable that functionality.  This function no longer
 948 * takes care of that.
 949 */
 950int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
 951			const char *mod_name)
 952{
 953	int retval = 0;
 954
 955	if (usb_disabled())
 956		return -ENODEV;
 957
 958	new_driver->drvwrap.for_devices = 0;
 959	new_driver->drvwrap.driver.name = new_driver->name;
 960	new_driver->drvwrap.driver.bus = &usb_bus_type;
 961	new_driver->drvwrap.driver.probe = usb_probe_interface;
 962	new_driver->drvwrap.driver.remove = usb_unbind_interface;
 963	new_driver->drvwrap.driver.owner = owner;
 964	new_driver->drvwrap.driver.mod_name = mod_name;
 965	spin_lock_init(&new_driver->dynids.lock);
 966	INIT_LIST_HEAD(&new_driver->dynids.list);
 967
 968	retval = driver_register(&new_driver->drvwrap.driver);
 969	if (retval)
 970		goto out;
 971
 972	retval = usb_create_newid_files(new_driver);
 973	if (retval)
 974		goto out_newid;
 975
 976	pr_info("%s: registered new interface driver %s\n",
 977			usbcore_name, new_driver->name);
 978
 979out:
 980	return retval;
 981
 982out_newid:
 983	driver_unregister(&new_driver->drvwrap.driver);
 984
 985	printk(KERN_ERR "%s: error %d registering interface "
 986			"	driver %s\n",
 987			usbcore_name, retval, new_driver->name);
 988	goto out;
 989}
 990EXPORT_SYMBOL_GPL(usb_register_driver);
 991
 992/**
 993 * usb_deregister - unregister a USB interface driver
 994 * @driver: USB operations of the interface driver to unregister
 995 * Context: must be able to sleep
 996 *
 997 * Unlinks the specified driver from the internal USB driver list.
 998 *
 999 * NOTE: If you called usb_register_dev(), you still need to call
1000 * usb_deregister_dev() to clean up your driver's allocated minor numbers,
1001 * this * call will no longer do it for you.
1002 */
1003void usb_deregister(struct usb_driver *driver)
1004{
1005	pr_info("%s: deregistering interface driver %s\n",
1006			usbcore_name, driver->name);
1007
1008	usb_remove_newid_files(driver);
1009	driver_unregister(&driver->drvwrap.driver);
1010	usb_free_dynids(driver);
1011}
1012EXPORT_SYMBOL_GPL(usb_deregister);
1013
1014/* Forced unbinding of a USB interface driver, either because
1015 * it doesn't support pre_reset/post_reset/reset_resume or
1016 * because it doesn't support suspend/resume.
1017 *
1018 * The caller must hold @intf's device's lock, but not @intf's lock.
1019 */
1020void usb_forced_unbind_intf(struct usb_interface *intf)
1021{
1022	struct usb_driver *driver = to_usb_driver(intf->dev.driver);
1023
1024	dev_dbg(&intf->dev, "forced unbind\n");
1025	usb_driver_release_interface(driver, intf);
1026
1027	/* Mark the interface for later rebinding */
1028	intf->needs_binding = 1;
1029}
1030
1031/*
1032 * Unbind drivers for @udev's marked interfaces.  These interfaces have
1033 * the needs_binding flag set, for example by usb_resume_interface().
1034 *
1035 * The caller must hold @udev's device lock.
1036 */
1037static void unbind_marked_interfaces(struct usb_device *udev)
1038{
1039	struct usb_host_config	*config;
1040	int			i;
1041	struct usb_interface	*intf;
1042
1043	config = udev->actconfig;
1044	if (config) {
1045		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1046			intf = config->interface[i];
1047			if (intf->dev.driver && intf->needs_binding)
1048				usb_forced_unbind_intf(intf);
1049		}
1050	}
1051}
1052
1053/* Delayed forced unbinding of a USB interface driver and scan
1054 * for rebinding.
1055 *
1056 * The caller must hold @intf's device's lock, but not @intf's lock.
1057 *
1058 * Note: Rebinds will be skipped if a system sleep transition is in
1059 * progress and the PM "complete" callback hasn't occurred yet.
1060 */
1061static void usb_rebind_intf(struct usb_interface *intf)
1062{
1063	int rc;
1064
1065	/* Delayed unbind of an existing driver */
1066	if (intf->dev.driver)
1067		usb_forced_unbind_intf(intf);
1068
1069	/* Try to rebind the interface */
1070	if (!intf->dev.power.is_prepared) {
1071		intf->needs_binding = 0;
1072		rc = device_attach(&intf->dev);
1073		if (rc < 0)
1074			dev_warn(&intf->dev, "rebind failed: %d\n", rc);
1075	}
1076}
1077
1078/*
1079 * Rebind drivers to @udev's marked interfaces.  These interfaces have
1080 * the needs_binding flag set.
1081 *
1082 * The caller must hold @udev's device lock.
1083 */
1084static void rebind_marked_interfaces(struct usb_device *udev)
1085{
1086	struct usb_host_config	*config;
1087	int			i;
1088	struct usb_interface	*intf;
1089
1090	config = udev->actconfig;
1091	if (config) {
1092		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1093			intf = config->interface[i];
1094			if (intf->needs_binding)
1095				usb_rebind_intf(intf);
1096		}
1097	}
1098}
1099
1100/*
1101 * Unbind all of @udev's marked interfaces and then rebind all of them.
1102 * This ordering is necessary because some drivers claim several interfaces
1103 * when they are first probed.
1104 *
1105 * The caller must hold @udev's device lock.
1106 */
1107void usb_unbind_and_rebind_marked_interfaces(struct usb_device *udev)
1108{
1109	unbind_marked_interfaces(udev);
1110	rebind_marked_interfaces(udev);
1111}
1112
1113#ifdef CONFIG_PM
1114
1115/* Unbind drivers for @udev's interfaces that don't support suspend/resume
1116 * There is no check for reset_resume here because it can be determined
1117 * only during resume whether reset_resume is needed.
1118 *
1119 * The caller must hold @udev's device lock.
1120 */
1121static void unbind_no_pm_drivers_interfaces(struct usb_device *udev)
1122{
1123	struct usb_host_config	*config;
1124	int			i;
1125	struct usb_interface	*intf;
1126	struct usb_driver	*drv;
1127
1128	config = udev->actconfig;
1129	if (config) {
1130		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
1131			intf = config->interface[i];
1132
1133			if (intf->dev.driver) {
1134				drv = to_usb_driver(intf->dev.driver);
1135				if (!drv->suspend || !drv->resume)
1136					usb_forced_unbind_intf(intf);
1137			}
1138		}
1139	}
1140}
1141
1142static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
1143{
1144	struct usb_device_driver	*udriver;
1145	int				status = 0;
1146
1147	if (udev->state == USB_STATE_NOTATTACHED ||
1148			udev->state == USB_STATE_SUSPENDED)
1149		goto done;
1150
1151	/* For devices that don't have a driver, we do a generic suspend. */
1152	if (udev->dev.driver)
1153		udriver = to_usb_device_driver(udev->dev.driver);
1154	else {
1155		udev->do_remote_wakeup = 0;
1156		udriver = &usb_generic_driver;
1157	}
1158	status = udriver->suspend(udev, msg);
1159
1160 done:
1161	dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1162	return status;
1163}
1164
1165static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
1166{
1167	struct usb_device_driver	*udriver;
1168	int				status = 0;
1169
1170	if (udev->state == USB_STATE_NOTATTACHED)
1171		goto done;
1172
1173	/* Can't resume it if it doesn't have a driver. */
1174	if (udev->dev.driver == NULL) {
1175		status = -ENOTCONN;
1176		goto done;
1177	}
1178
1179	/* Non-root devices on a full/low-speed bus must wait for their
1180	 * companion high-speed root hub, in case a handoff is needed.
1181	 */
1182	if (!PMSG_IS_AUTO(msg) && udev->parent && udev->bus->hs_companion)
1183		device_pm_wait_for_dev(&udev->dev,
1184				&udev->bus->hs_companion->root_hub->dev);
1185
1186	if (udev->quirks & USB_QUIRK_RESET_RESUME)
1187		udev->reset_resume = 1;
1188
1189	udriver = to_usb_device_driver(udev->dev.driver);
1190	status = udriver->resume(udev, msg);
1191
1192 done:
1193	dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1194	return status;
1195}
1196
1197static int usb_suspend_interface(struct usb_device *udev,
1198		struct usb_interface *intf, pm_message_t msg)
1199{
1200	struct usb_driver	*driver;
1201	int			status = 0;
1202
1203	if (udev->state == USB_STATE_NOTATTACHED ||
1204			intf->condition == USB_INTERFACE_UNBOUND)
1205		goto done;
1206	driver = to_usb_driver(intf->dev.driver);
1207
1208	/* at this time we know the driver supports suspend */
1209	status = driver->suspend(intf, msg);
1210	if (status && !PMSG_IS_AUTO(msg))
1211		dev_err(&intf->dev, "suspend error %d\n", status);
1212
1213 done:
1214	dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1215	return status;
1216}
1217
1218static int usb_resume_interface(struct usb_device *udev,
1219		struct usb_interface *intf, pm_message_t msg, int reset_resume)
1220{
1221	struct usb_driver	*driver;
1222	int			status = 0;
1223
1224	if (udev->state == USB_STATE_NOTATTACHED)
1225		goto done;
1226
1227	/* Don't let autoresume interfere with unbinding */
1228	if (intf->condition == USB_INTERFACE_UNBINDING)
1229		goto done;
1230
1231	/* Can't resume it if it doesn't have a driver. */
1232	if (intf->condition == USB_INTERFACE_UNBOUND) {
1233
1234		/* Carry out a deferred switch to altsetting 0 */
1235		if (intf->needs_altsetting0 && !intf->dev.power.is_prepared) {
1236			usb_set_interface(udev, intf->altsetting[0].
1237					desc.bInterfaceNumber, 0);
1238			intf->needs_altsetting0 = 0;
1239		}
1240		goto done;
1241	}
1242
1243	/* Don't resume if the interface is marked for rebinding */
1244	if (intf->needs_binding)
1245		goto done;
1246	driver = to_usb_driver(intf->dev.driver);
1247
1248	if (reset_resume) {
1249		if (driver->reset_resume) {
1250			status = driver->reset_resume(intf);
1251			if (status)
1252				dev_err(&intf->dev, "%s error %d\n",
1253						"reset_resume", status);
1254		} else {
1255			intf->needs_binding = 1;
1256			dev_dbg(&intf->dev, "no reset_resume for driver %s?\n",
1257					driver->name);
1258		}
1259	} else {
1260		status = driver->resume(intf);
1261		if (status)
1262			dev_err(&intf->dev, "resume error %d\n", status);
1263	}
1264
1265done:
1266	dev_vdbg(&intf->dev, "%s: status %d\n", __func__, status);
1267
1268	/* Later we will unbind the driver and/or reprobe, if necessary */
1269	return status;
1270}
1271
1272/**
1273 * usb_suspend_both - suspend a USB device and its interfaces
1274 * @udev: the usb_device to suspend
1275 * @msg: Power Management message describing this state transition
1276 *
1277 * This is the central routine for suspending USB devices.  It calls the
1278 * suspend methods for all the interface drivers in @udev and then calls
1279 * the suspend method for @udev itself.  When the routine is called in
1280 * autosuspend, if an error occurs at any stage, all the interfaces
1281 * which were suspended are resumed so that they remain in the same
1282 * state as the device, but when called from system sleep, all error
1283 * from suspend methods of interfaces and the non-root-hub device itself
1284 * are simply ignored, so all suspended interfaces are only resumed
1285 * to the device's state when @udev is root-hub and its suspend method
1286 * returns failure.
1287 *
1288 * Autosuspend requests originating from a child device or an interface
1289 * driver may be made without the protection of @udev's device lock, but
1290 * all other suspend calls will hold the lock.  Usbcore will insure that
1291 * method calls do not arrive during bind, unbind, or reset operations.
1292 * However drivers must be prepared to handle suspend calls arriving at
1293 * unpredictable times.
1294 *
1295 * This routine can run only in process context.
1296 *
1297 * Return: 0 if the suspend succeeded.
1298 */
1299static int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
1300{
1301	int			status = 0;
1302	int			i = 0, n = 0;
1303	struct usb_interface	*intf;
1304
1305	if (udev->state == USB_STATE_NOTATTACHED ||
1306			udev->state == USB_STATE_SUSPENDED)
1307		goto done;
1308
1309	/* Suspend all the interfaces and then udev itself */
1310	if (udev->actconfig) {
1311		n = udev->actconfig->desc.bNumInterfaces;
1312		for (i = n - 1; i >= 0; --i) {
1313			intf = udev->actconfig->interface[i];
1314			status = usb_suspend_interface(udev, intf, msg);
1315
1316			/* Ignore errors during system sleep transitions */
1317			if (!PMSG_IS_AUTO(msg))
1318				status = 0;
1319			if (status != 0)
1320				break;
1321		}
1322	}
1323	if (status == 0) {
1324		status = usb_suspend_device(udev, msg);
1325
1326		/*
1327		 * Ignore errors from non-root-hub devices during
1328		 * system sleep transitions.  For the most part,
1329		 * these devices should go to low power anyway when
1330		 * the entire bus is suspended.
1331		 */
1332		if (udev->parent && !PMSG_IS_AUTO(msg))
1333			status = 0;
1334	}
1335
1336	/* If the suspend failed, resume interfaces that did get suspended */
1337	if (status != 0) {
1338		if (udev->actconfig) {
1339			msg.event ^= (PM_EVENT_SUSPEND | PM_EVENT_RESUME);
1340			while (++i < n) {
1341				intf = udev->actconfig->interface[i];
1342				usb_resume_interface(udev, intf, msg, 0);
1343			}
1344		}
1345
1346	/* If the suspend succeeded then prevent any more URB submissions
1347	 * and flush any outstanding URBs.
1348	 */
1349	} else {
1350		udev->can_submit = 0;
1351		for (i = 0; i < 16; ++i) {
1352			usb_hcd_flush_endpoint(udev, udev->ep_out[i]);
1353			usb_hcd_flush_endpoint(udev, udev->ep_in[i]);
1354		}
1355	}
1356
1357 done:
1358	dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1359	return status;
1360}
1361
1362/**
1363 * usb_resume_both - resume a USB device and its interfaces
1364 * @udev: the usb_device to resume
1365 * @msg: Power Management message describing this state transition
1366 *
1367 * This is the central routine for resuming USB devices.  It calls the
1368 * the resume method for @udev and then calls the resume methods for all
1369 * the interface drivers in @udev.
1370 *
1371 * Autoresume requests originating from a child device or an interface
1372 * driver may be made without the protection of @udev's device lock, but
1373 * all other resume calls will hold the lock.  Usbcore will insure that
1374 * method calls do not arrive during bind, unbind, or reset operations.
1375 * However drivers must be prepared to handle resume calls arriving at
1376 * unpredictable times.
1377 *
1378 * This routine can run only in process context.
1379 *
1380 * Return: 0 on success.
1381 */
1382static int usb_resume_both(struct usb_device *udev, pm_message_t msg)
1383{
1384	int			status = 0;
1385	int			i;
1386	struct usb_interface	*intf;
1387
1388	if (udev->state == USB_STATE_NOTATTACHED) {
1389		status = -ENODEV;
1390		goto done;
1391	}
1392	udev->can_submit = 1;
1393
1394	/* Resume the device */
1395	if (udev->state == USB_STATE_SUSPENDED || udev->reset_resume)
1396		status = usb_resume_device(udev, msg);
1397
1398	/* Resume the interfaces */
1399	if (status == 0 && udev->actconfig) {
1400		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1401			intf = udev->actconfig->interface[i];
1402			usb_resume_interface(udev, intf, msg,
1403					udev->reset_resume);
1404		}
1405	}
1406	usb_mark_last_busy(udev);
1407
1408 done:
1409	dev_vdbg(&udev->dev, "%s: status %d\n", __func__, status);
1410	if (!status)
1411		udev->reset_resume = 0;
1412	return status;
1413}
1414
1415static void choose_wakeup(struct usb_device *udev, pm_message_t msg)
1416{
1417	int	w;
1418
1419	/* Remote wakeup is needed only when we actually go to sleep.
1420	 * For things like FREEZE and QUIESCE, if the device is already
1421	 * autosuspended then its current wakeup setting is okay.
1422	 */
1423	if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) {
1424		if (udev->state != USB_STATE_SUSPENDED)
1425			udev->do_remote_wakeup = 0;
1426		return;
1427	}
1428
1429	/* Enable remote wakeup if it is allowed, even if no interface drivers
1430	 * actually want it.
1431	 */
1432	w = device_may_wakeup(&udev->dev);
1433
1434	/* If the device is autosuspended with the wrong wakeup setting,
1435	 * autoresume now so the setting can be changed.
1436	 */
1437	if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup)
1438		pm_runtime_resume(&udev->dev);
1439	udev->do_remote_wakeup = w;
1440}
1441
1442/* The device lock is held by the PM core */
1443int usb_suspend(struct device *dev, pm_message_t msg)
1444{
1445	struct usb_device	*udev = to_usb_device(dev);
1446
1447	unbind_no_pm_drivers_interfaces(udev);
1448
1449	/* From now on we are sure all drivers support suspend/resume
1450	 * but not necessarily reset_resume()
1451	 * so we may still need to unbind and rebind upon resume
1452	 */
1453	choose_wakeup(udev, msg);
1454	return usb_suspend_both(udev, msg);
1455}
1456
1457/* The device lock is held by the PM core */
1458int usb_resume_complete(struct device *dev)
1459{
1460	struct usb_device *udev = to_usb_device(dev);
1461
1462	/* For PM complete calls, all we do is rebind interfaces
1463	 * whose needs_binding flag is set
1464	 */
1465	if (udev->state != USB_STATE_NOTATTACHED)
1466		rebind_marked_interfaces(udev);
1467	return 0;
1468}
1469
1470/* The device lock is held by the PM core */
1471int usb_resume(struct device *dev, pm_message_t msg)
1472{
1473	struct usb_device	*udev = to_usb_device(dev);
1474	int			status;
1475
1476	/* For all calls, take the device back to full power and
1477	 * tell the PM core in case it was autosuspended previously.
1478	 * Unbind the interfaces that will need rebinding later,
1479	 * because they fail to support reset_resume.
1480	 * (This can't be done in usb_resume_interface()
1481	 * above because it doesn't own the right set of locks.)
1482	 */
1483	status = usb_resume_both(udev, msg);
1484	if (status == 0) {
1485		pm_runtime_disable(dev);
1486		pm_runtime_set_active(dev);
1487		pm_runtime_enable(dev);
1488		unbind_marked_interfaces(udev);
1489	}
1490
1491	/* Avoid PM error messages for devices disconnected while suspended
1492	 * as we'll display regular disconnect messages just a bit later.
1493	 */
1494	if (status == -ENODEV || status == -ESHUTDOWN)
1495		status = 0;
1496	return status;
1497}
1498
1499/**
1500 * usb_enable_autosuspend - allow a USB device to be autosuspended
1501 * @udev: the USB device which may be autosuspended
1502 *
1503 * This routine allows @udev to be autosuspended.  An autosuspend won't
1504 * take place until the autosuspend_delay has elapsed and all the other
1505 * necessary conditions are satisfied.
1506 *
1507 * The caller must hold @udev's device lock.
1508 */
1509void usb_enable_autosuspend(struct usb_device *udev)
1510{
1511	pm_runtime_allow(&udev->dev);
1512}
1513EXPORT_SYMBOL_GPL(usb_enable_autosuspend);
1514
1515/**
1516 * usb_disable_autosuspend - prevent a USB device from being autosuspended
1517 * @udev: the USB device which may not be autosuspended
1518 *
1519 * This routine prevents @udev from being autosuspended and wakes it up
1520 * if it is already autosuspended.
1521 *
1522 * The caller must hold @udev's device lock.
1523 */
1524void usb_disable_autosuspend(struct usb_device *udev)
1525{
1526	pm_runtime_forbid(&udev->dev);
1527}
1528EXPORT_SYMBOL_GPL(usb_disable_autosuspend);
1529
1530/**
1531 * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
1532 * @udev: the usb_device to autosuspend
1533 *
1534 * This routine should be called when a core subsystem is finished using
1535 * @udev and wants to allow it to autosuspend.  Examples would be when
1536 * @udev's device file in usbfs is closed or after a configuration change.
1537 *
1538 * @udev's usage counter is decremented; if it drops to 0 and all the
1539 * interfaces are inactive then a delayed autosuspend will be attempted.
1540 * The attempt may fail (see autosuspend_check()).
1541 *
1542 * The caller must hold @udev's device lock.
1543 *
1544 * This routine can run only in process context.
1545 */
1546void usb_autosuspend_device(struct usb_device *udev)
1547{
1548	int	status;
1549
1550	usb_mark_last_busy(udev);
1551	status = pm_runtime_put_sync_autosuspend(&udev->dev);
1552	dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1553			__func__, atomic_read(&udev->dev.power.usage_count),
1554			status);
1555}
1556
1557/**
1558 * usb_autoresume_device - immediately autoresume a USB device and its interfaces
1559 * @udev: the usb_device to autoresume
1560 *
1561 * This routine should be called when a core subsystem wants to use @udev
1562 * and needs to guarantee that it is not suspended.  No autosuspend will
1563 * occur until usb_autosuspend_device() is called.  (Note that this will
1564 * not prevent suspend events originating in the PM core.)  Examples would
1565 * be when @udev's device file in usbfs is opened or when a remote-wakeup
1566 * request is received.
1567 *
1568 * @udev's usage counter is incremented to prevent subsequent autosuspends.
1569 * However if the autoresume fails then the usage counter is re-decremented.
1570 *
1571 * The caller must hold @udev's device lock.
1572 *
1573 * This routine can run only in process context.
1574 *
1575 * Return: 0 on success. A negative error code otherwise.
1576 */
1577int usb_autoresume_device(struct usb_device *udev)
1578{
1579	int	status;
1580
1581	status = pm_runtime_get_sync(&udev->dev);
1582	if (status < 0)
1583		pm_runtime_put_sync(&udev->dev);
1584	dev_vdbg(&udev->dev, "%s: cnt %d -> %d\n",
1585			__func__, atomic_read(&udev->dev.power.usage_count),
1586			status);
1587	if (status > 0)
1588		status = 0;
1589	return status;
1590}
1591
1592/**
1593 * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
1594 * @intf: the usb_interface whose counter should be decremented
1595 *
1596 * This routine should be called by an interface driver when it is
1597 * finished using @intf and wants to allow it to autosuspend.  A typical
1598 * example would be a character-device driver when its device file is
1599 * closed.
1600 *
1601 * The routine decrements @intf's usage counter.  When the counter reaches
1602 * 0, a delayed autosuspend request for @intf's device is attempted.  The
1603 * attempt may fail (see autosuspend_check()).
1604 *
1605 * This routine can run only in process context.
1606 */
1607void usb_autopm_put_interface(struct usb_interface *intf)
1608{
1609	struct usb_device	*udev = interface_to_usbdev(intf);
1610	int			status;
1611
1612	usb_mark_last_busy(udev);
1613	atomic_dec(&intf->pm_usage_cnt);
1614	status = pm_runtime_put_sync(&intf->dev);
1615	dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1616			__func__, atomic_read(&intf->dev.power.usage_count),
1617			status);
1618}
1619EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
1620
1621/**
1622 * usb_autopm_put_interface_async - decrement a USB interface's PM-usage counter
1623 * @intf: the usb_interface whose counter should be decremented
1624 *
1625 * This routine does much the same thing as usb_autopm_put_interface():
1626 * It decrements @intf's usage counter and schedules a delayed
1627 * autosuspend request if the counter is <= 0.  The difference is that it
1628 * does not perform any synchronization; callers should hold a private
1629 * lock and handle all synchronization issues themselves.
1630 *
1631 * Typically a driver would call this routine during an URB's completion
1632 * handler, if no more URBs were pending.
1633 *
1634 * This routine can run in atomic context.
1635 */
1636void usb_autopm_put_interface_async(struct usb_interface *intf)
1637{
1638	struct usb_device	*udev = interface_to_usbdev(intf);
1639	int			status;
1640
1641	usb_mark_last_busy(udev);
1642	atomic_dec(&intf->pm_usage_cnt);
1643	status = pm_runtime_put(&intf->dev);
1644	dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1645			__func__, atomic_read(&intf->dev.power.usage_count),
1646			status);
1647}
1648EXPORT_SYMBOL_GPL(usb_autopm_put_interface_async);
1649
1650/**
1651 * usb_autopm_put_interface_no_suspend - decrement a USB interface's PM-usage counter
1652 * @intf: the usb_interface whose counter should be decremented
1653 *
1654 * This routine decrements @intf's usage counter but does not carry out an
1655 * autosuspend.
1656 *
1657 * This routine can run in atomic context.
1658 */
1659void usb_autopm_put_interface_no_suspend(struct usb_interface *intf)
1660{
1661	struct usb_device	*udev = interface_to_usbdev(intf);
1662
1663	usb_mark_last_busy(udev);
1664	atomic_dec(&intf->pm_usage_cnt);
1665	pm_runtime_put_noidle(&intf->dev);
1666}
1667EXPORT_SYMBOL_GPL(usb_autopm_put_interface_no_suspend);
1668
1669/**
1670 * usb_autopm_get_interface - increment a USB interface's PM-usage counter
1671 * @intf: the usb_interface whose counter should be incremented
1672 *
1673 * This routine should be called by an interface driver when it wants to
1674 * use @intf and needs to guarantee that it is not suspended.  In addition,
1675 * the routine prevents @intf from being autosuspended subsequently.  (Note
1676 * that this will not prevent suspend events originating in the PM core.)
1677 * This prevention will persist until usb_autopm_put_interface() is called
1678 * or @intf is unbound.  A typical example would be a character-device
1679 * driver when its device file is opened.
1680 *
1681 * @intf's usage counter is incremented to prevent subsequent autosuspends.
1682 * However if the autoresume fails then the counter is re-decremented.
1683 *
1684 * This routine can run only in process context.
1685 *
1686 * Return: 0 on success.
1687 */
1688int usb_autopm_get_interface(struct usb_interface *intf)
1689{
1690	int	status;
1691
1692	status = pm_runtime_get_sync(&intf->dev);
1693	if (status < 0)
1694		pm_runtime_put_sync(&intf->dev);
1695	else
1696		atomic_inc(&intf->pm_usage_cnt);
1697	dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1698			__func__, atomic_read(&intf->dev.power.usage_count),
1699			status);
1700	if (status > 0)
1701		status = 0;
1702	return status;
1703}
1704EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
1705
1706/**
1707 * usb_autopm_get_interface_async - increment a USB interface's PM-usage counter
1708 * @intf: the usb_interface whose counter should be incremented
1709 *
1710 * This routine does much the same thing as
1711 * usb_autopm_get_interface(): It increments @intf's usage counter and
1712 * queues an autoresume request if the device is suspended.  The
1713 * differences are that it does not perform any synchronization (callers
1714 * should hold a private lock and handle all synchronization issues
1715 * themselves), and it does not autoresume the device directly (it only
1716 * queues a request).  After a successful call, the device may not yet be
1717 * resumed.
1718 *
1719 * This routine can run in atomic context.
1720 *
1721 * Return: 0 on success. A negative error code otherwise.
1722 */
1723int usb_autopm_get_interface_async(struct usb_interface *intf)
1724{
1725	int	status;
1726
1727	status = pm_runtime_get(&intf->dev);
1728	if (status < 0 && status != -EINPROGRESS)
1729		pm_runtime_put_noidle(&intf->dev);
1730	else
1731		atomic_inc(&intf->pm_usage_cnt);
1732	dev_vdbg(&intf->dev, "%s: cnt %d -> %d\n",
1733			__func__, atomic_read(&intf->dev.power.usage_count),
1734			status);
1735	if (status > 0 || status == -EINPROGRESS)
1736		status = 0;
1737	return status;
1738}
1739EXPORT_SYMBOL_GPL(usb_autopm_get_interface_async);
1740
1741/**
1742 * usb_autopm_get_interface_no_resume - increment a USB interface's PM-usage counter
1743 * @intf: the usb_interface whose counter should be incremented
1744 *
1745 * This routine increments @intf's usage counter but does not carry out an
1746 * autoresume.
1747 *
1748 * This routine can run in atomic context.
1749 */
1750void usb_autopm_get_interface_no_resume(struct usb_interface *intf)
1751{
1752	struct usb_device	*udev = interface_to_usbdev(intf);
1753
1754	usb_mark_last_busy(udev);
1755	atomic_inc(&intf->pm_usage_cnt);
1756	pm_runtime_get_noresume(&intf->dev);
1757}
1758EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume);
1759
1760/* Internal routine to check whether we may autosuspend a device. */
1761static int autosuspend_check(struct usb_device *udev)
1762{
1763	int			w, i;
1764	struct usb_interface	*intf;
1765
1766	/* Fail if autosuspend is disabled, or any interfaces are in use, or
1767	 * any interface drivers require remote wakeup but it isn't available.
1768	 */
1769	w = 0;
1770	if (udev->actconfig) {
1771		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1772			intf = udev->actconfig->interface[i];
1773
1774			/* We don't need to check interfaces that are
1775			 * disabled for runtime PM.  Either they are unbound
1776			 * or else their drivers don't support autosuspend
1777			 * and so they are permanently active.
1778			 */
1779			if (intf->dev.power.disable_depth)
1780				continue;
1781			if (atomic_read(&intf->dev.power.usage_count) > 0)
1782				return -EBUSY;
1783			w |= intf->needs_remote_wakeup;
1784
1785			/* Don't allow autosuspend if the device will need
1786			 * a reset-resume and any of its interface drivers
1787			 * doesn't include support or needs remote wakeup.
1788			 */
1789			if (udev->quirks & USB_QUIRK_RESET_RESUME) {
1790				struct usb_driver *driver;
1791
1792				driver = to_usb_driver(intf->dev.driver);
1793				if (!driver->reset_resume ||
1794						intf->needs_remote_wakeup)
1795					return -EOPNOTSUPP;
1796			}
1797		}
1798	}
1799	if (w && !device_can_wakeup(&udev->dev)) {
1800		dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n");
1801		return -EOPNOTSUPP;
1802	}
1803
1804	/*
1805	 * If the device is a direct child of the root hub and the HCD
1806	 * doesn't handle wakeup requests, don't allow autosuspend when
1807	 * wakeup is needed.
1808	 */
1809	if (w && udev->parent == udev->bus->root_hub &&
1810			bus_to_hcd(udev->bus)->cant_recv_wakeups) {
1811		dev_dbg(&udev->dev, "HCD doesn't handle wakeup requests\n");
1812		return -EOPNOTSUPP;
1813	}
1814
1815	udev->do_remote_wakeup = w;
1816	return 0;
1817}
1818
1819int usb_runtime_suspend(struct device *dev)
1820{
1821	struct usb_device	*udev = to_usb_device(dev);
1822	int			status;
1823
1824	/* A USB device can be suspended if it passes the various autosuspend
1825	 * checks.  Runtime suspend for a USB device means suspending all the
1826	 * interfaces and then the device itself.
1827	 */
1828	if (autosuspend_check(udev) != 0)
1829		return -EAGAIN;
1830
1831	status = usb_suspend_both(udev, PMSG_AUTO_SUSPEND);
1832
1833	/* Allow a retry if autosuspend failed temporarily */
1834	if (status == -EAGAIN || status == -EBUSY)
1835		usb_mark_last_busy(udev);
1836
1837	/*
1838	 * The PM core reacts badly unless the return code is 0,
1839	 * -EAGAIN, or -EBUSY, so always return -EBUSY on an error
1840	 * (except for root hubs, because they don't suspend through
1841	 * an upstream port like other USB devices).
1842	 */
1843	if (status != 0 && udev->parent)
1844		return -EBUSY;
1845	return status;
1846}
1847
1848int usb_runtime_resume(struct device *dev)
1849{
1850	struct usb_device	*udev = to_usb_device(dev);
1851	int			status;
1852
1853	/* Runtime resume for a USB device means resuming both the device
1854	 * and all its interfaces.
1855	 */
1856	status = usb_resume_both(udev, PMSG_AUTO_RESUME);
1857	return status;
1858}
1859
1860int usb_runtime_idle(struct device *dev)
1861{
1862	struct usb_device	*udev = to_usb_device(dev);
1863
1864	/* An idle USB device can be suspended if it passes the various
1865	 * autosuspend checks.
1866	 */
1867	if (autosuspend_check(udev) == 0)
1868		pm_runtime_autosuspend(dev);
1869	/* Tell the core not to suspend it, though. */
1870	return -EBUSY;
1871}
1872
1873int usb_set_usb2_hardware_lpm(struct usb_device *udev, int enable)
1874{
1875	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1876	int ret = -EPERM;
1877
1878	if (enable && !udev->usb2_hw_lpm_allowed)
1879		return 0;
1880
1881	if (hcd->driver->set_usb2_hw_lpm) {
1882		ret = hcd->driver->set_usb2_hw_lpm(hcd, udev, enable);
1883		if (!ret)
1884			udev->usb2_hw_lpm_enabled = enable;
1885	}
1886
1887	return ret;
1888}
1889
1890#endif /* CONFIG_PM */
1891
1892struct bus_type usb_bus_type = {
1893	.name =		"usb",
1894	.match =	usb_device_match,
1895	.uevent =	usb_uevent,
1896};