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