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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Uwe Zeisbergerf30c2262006-10-03 23:01:26 +02002 * drivers/usb/core/usb.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * (C) Copyright Linus Torvalds 1999
5 * (C) Copyright Johannes Erdfelt 1999-2001
6 * (C) Copyright Andreas Gal 1999
7 * (C) Copyright Gregory P. Smith 1999
8 * (C) Copyright Deti Fliegl 1999 (new USB architecture)
9 * (C) Copyright Randy Dunlap 2000
10 * (C) Copyright David Brownell 2000-2004
11 * (C) Copyright Yggdrasil Computing, Inc. 2000
12 * (usb_device_id matching changes by Adam J. Richter)
13 * (C) Copyright Greg Kroah-Hartman 2002-2003
14 *
15 * NOTE! This is not actually a driver at all, rather this is
16 * just a collection of helper routines that implement the
17 * generic USB things that the real drivers can use..
18 *
19 * Think of this as a "USB library" rather than anything else.
20 * It should be considered a slave, with no callbacks. Callbacks
21 * are evil.
22 */
23
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/module.h>
Alan Sternb5e795f2007-02-20 15:00:53 -050025#include <linux/moduleparam.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/string.h>
27#include <linux/bitops.h>
28#include <linux/slab.h>
29#include <linux/interrupt.h> /* for in_interrupt() */
30#include <linux/kmod.h>
31#include <linux/init.h>
32#include <linux/spinlock.h>
33#include <linux/errno.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/usb.h>
Arjan van de Ven4186ecf2006-01-11 15:55:29 +010035#include <linux/mutex.h>
Alan Sternbd859282006-09-19 10:14:07 -040036#include <linux/workqueue.h>
Greg Kroah-Hartman00048b82009-04-24 14:56:26 -070037#include <linux/debugfs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39#include <asm/io.h>
Adrian Bunk87ae9af2007-10-30 10:35:04 +010040#include <linux/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041#include <linux/mm.h>
42#include <linux/dma-mapping.h>
43
44#include "hcd.h"
45#include "usb.h"
46
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
48const char *usbcore_name = "usbcore";
49
50static int nousb; /* Disable USB when built into kernel image */
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
Alan Stern6b157c92007-03-13 16:37:30 -040052/* Workqueue for autosuspend and for remote wakeup of root hubs */
53struct workqueue_struct *ksuspend_usb_wq;
Alan Sternbd859282006-09-19 10:14:07 -040054
Alan Sternb5e795f2007-02-20 15:00:53 -050055#ifdef CONFIG_USB_SUSPEND
56static int usb_autosuspend_delay = 2; /* Default delay value,
57 * in seconds */
Alan Sterneaafbc32007-03-13 16:39:15 -040058module_param_named(autosuspend, usb_autosuspend_delay, int, 0644);
Alan Sternb5e795f2007-02-20 15:00:53 -050059MODULE_PARM_DESC(autosuspend, "default autosuspend delay");
60
61#else
62#define usb_autosuspend_delay 0
63#endif
64
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
Linus Torvalds1da177e2005-04-16 15:20:36 -070066/**
67 * usb_ifnum_to_if - get the interface object with a given interface number
68 * @dev: the device whose current configuration is considered
69 * @ifnum: the desired interface
70 *
71 * This walks the device descriptor for the currently active configuration
72 * and returns a pointer to the interface with that particular interface
73 * number, or null.
74 *
75 * Note that configuration descriptors are not required to assign interface
76 * numbers sequentially, so that it would be incorrect to assume that
77 * the first interface in that descriptor corresponds to interface zero.
78 * This routine helps device drivers avoid such mistakes.
79 * However, you should make sure that you do the right thing with any
80 * alternate settings available for this interfaces.
81 *
82 * Don't call this function unless you are bound to one of the interfaces
83 * on this device or you have locked the device!
84 */
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -030085struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
86 unsigned ifnum)
Linus Torvalds1da177e2005-04-16 15:20:36 -070087{
88 struct usb_host_config *config = dev->actconfig;
89 int i;
90
91 if (!config)
92 return NULL;
93 for (i = 0; i < config->desc.bNumInterfaces; i++)
94 if (config->interface[i]->altsetting[0]
95 .desc.bInterfaceNumber == ifnum)
96 return config->interface[i];
97
98 return NULL;
99}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600100EXPORT_SYMBOL_GPL(usb_ifnum_to_if);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101
102/**
Randy Dunlapd0bcabc2008-02-29 22:03:07 -0800103 * usb_altnum_to_altsetting - get the altsetting structure with a given alternate setting number.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104 * @intf: the interface containing the altsetting in question
105 * @altnum: the desired alternate setting number
106 *
107 * This searches the altsetting array of the specified interface for
108 * an entry with the correct bAlternateSetting value and returns a pointer
109 * to that entry, or null.
110 *
111 * Note that altsettings need not be stored sequentially by number, so
112 * it would be incorrect to assume that the first altsetting entry in
113 * the array corresponds to altsetting zero. This routine helps device
114 * drivers avoid such mistakes.
115 *
116 * Don't call this function unless you are bound to the intf interface
117 * or you have locked the device!
118 */
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800119struct usb_host_interface *usb_altnum_to_altsetting(
120 const struct usb_interface *intf,
121 unsigned int altnum)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122{
123 int i;
124
125 for (i = 0; i < intf->num_altsetting; i++) {
126 if (intf->altsetting[i].desc.bAlternateSetting == altnum)
127 return &intf->altsetting[i];
128 }
129 return NULL;
130}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600131EXPORT_SYMBOL_GPL(usb_altnum_to_altsetting);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800133static int __find_interface(struct device *dev, void *data)
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800134{
Russ Dilla2582bd2009-11-18 11:02:13 -0700135 int *minor = data;
Pete Zaitcevf5691d72005-12-21 17:24:54 -0800136 struct usb_interface *intf;
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800137
Kay Sievers55129662009-05-04 19:48:32 +0200138 if (!is_usb_interface(dev))
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800139 return 0;
140
141 intf = to_usb_interface(dev);
Russ Dilla2582bd2009-11-18 11:02:13 -0700142 if (intf->minor != -1 && intf->minor == *minor)
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800143 return 1;
mochel@digitalimplant.org6034a082005-03-21 11:09:40 -0800144 return 0;
145}
146
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147/**
148 * usb_find_interface - find usb_interface pointer for driver and device
149 * @drv: the driver whose current configuration is considered
150 * @minor: the minor number of the desired device
151 *
Russ Dilla2582bd2009-11-18 11:02:13 -0700152 * This walks the bus device list and returns a pointer to the interface
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 * with the matching minor. Note, this only works for devices that share the
154 * USB major number.
155 */
156struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor)
157{
Russ Dilla2582bd2009-11-18 11:02:13 -0700158 struct device *dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159
Russ Dilla2582bd2009-11-18 11:02:13 -0700160 dev = bus_find_device(&usb_bus_type, NULL, &minor, __find_interface);
161
162 /* Drop reference count from bus_find_device */
163 put_device(dev);
164
165 return dev ? to_usb_interface(dev) : NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600167EXPORT_SYMBOL_GPL(usb_find_interface);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169/**
170 * usb_release_dev - free a usb device structure when all users of it are finished.
171 * @dev: device that's been disconnected
172 *
173 * Will be called only by the device core when all users of this usb device are
174 * done.
175 */
176static void usb_release_dev(struct device *dev)
177{
178 struct usb_device *udev;
Sarah Sharpc6515272009-04-27 19:57:26 -0700179 struct usb_hcd *hcd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180
181 udev = to_usb_device(dev);
Sarah Sharpc6515272009-04-27 19:57:26 -0700182 hcd = bus_to_hcd(udev->bus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183
184 usb_destroy_configuration(udev);
Sarah Sharpc6515272009-04-27 19:57:26 -0700185 /* Root hubs aren't real devices, so don't free HCD resources */
186 if (hcd->driver->free_dev && udev->parent)
187 hcd->driver->free_dev(hcd, udev);
188 usb_put_hcd(hcd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 kfree(udev->product);
190 kfree(udev->manufacturer);
191 kfree(udev->serial);
192 kfree(udev);
193}
194
Alan Stern4a9bee82007-11-06 15:01:52 -0500195#ifdef CONFIG_HOTPLUG
196static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
197{
198 struct usb_device *usb_dev;
199
200 usb_dev = to_usb_device(dev);
201
202 if (add_uevent_var(env, "BUSNUM=%03d", usb_dev->bus->busnum))
203 return -ENOMEM;
204
205 if (add_uevent_var(env, "DEVNUM=%03d", usb_dev->devnum))
206 return -ENOMEM;
207
208 return 0;
209}
210
211#else
212
213static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
214{
215 return -ENODEV;
216}
217#endif /* CONFIG_HOTPLUG */
218
Alan Stern645daaa2006-08-30 15:47:02 -0400219#ifdef CONFIG_PM
220
Alan Sternbd859282006-09-19 10:14:07 -0400221static int ksuspend_usb_init(void)
222{
Alan Stern7ed92f12007-05-22 09:38:39 -0400223 /* This workqueue is supposed to be both freezable and
224 * singlethreaded. Its job doesn't justify running on more
225 * than one CPU.
226 */
Rafael J. Wysocki7a8d37a2008-02-25 00:35:04 +0100227 ksuspend_usb_wq = create_freezeable_workqueue("ksuspend_usbd");
Alan Sternbd859282006-09-19 10:14:07 -0400228 if (!ksuspend_usb_wq)
229 return -ENOMEM;
230 return 0;
231}
232
233static void ksuspend_usb_cleanup(void)
234{
235 destroy_workqueue(ksuspend_usb_wq);
236}
237
Alan Sternf2189c42008-08-12 14:34:10 -0400238/* USB device Power-Management thunks.
239 * There's no need to distinguish here between quiescing a USB device
240 * and powering it down; the generic_suspend() routine takes care of
241 * it by skipping the usb_port_suspend() call for a quiesce. And for
242 * USB interfaces there's no difference at all.
243 */
244
245static int usb_dev_prepare(struct device *dev)
246{
247 return 0; /* Implement eventually? */
248}
249
250static void usb_dev_complete(struct device *dev)
251{
252 /* Currently used only for rebinding interfaces */
Alan Stern65bfd292008-11-25 16:39:18 -0500253 usb_resume(dev, PMSG_RESUME); /* Message event is meaningless */
Alan Sternf2189c42008-08-12 14:34:10 -0400254}
255
256static int usb_dev_suspend(struct device *dev)
257{
258 return usb_suspend(dev, PMSG_SUSPEND);
259}
260
261static int usb_dev_resume(struct device *dev)
262{
Alan Stern65bfd292008-11-25 16:39:18 -0500263 return usb_resume(dev, PMSG_RESUME);
Alan Sternf2189c42008-08-12 14:34:10 -0400264}
265
266static int usb_dev_freeze(struct device *dev)
267{
268 return usb_suspend(dev, PMSG_FREEZE);
269}
270
271static int usb_dev_thaw(struct device *dev)
272{
Alan Stern65bfd292008-11-25 16:39:18 -0500273 return usb_resume(dev, PMSG_THAW);
Alan Sternf2189c42008-08-12 14:34:10 -0400274}
275
276static int usb_dev_poweroff(struct device *dev)
277{
278 return usb_suspend(dev, PMSG_HIBERNATE);
279}
280
281static int usb_dev_restore(struct device *dev)
282{
Alan Stern65bfd292008-11-25 16:39:18 -0500283 return usb_resume(dev, PMSG_RESTORE);
Alan Sternf2189c42008-08-12 14:34:10 -0400284}
285
Rafael J. Wysockiadf09492008-10-06 22:46:05 +0200286static struct dev_pm_ops usb_device_pm_ops = {
Alan Sternf2189c42008-08-12 14:34:10 -0400287 .prepare = usb_dev_prepare,
288 .complete = usb_dev_complete,
289 .suspend = usb_dev_suspend,
290 .resume = usb_dev_resume,
291 .freeze = usb_dev_freeze,
292 .thaw = usb_dev_thaw,
293 .poweroff = usb_dev_poweroff,
294 .restore = usb_dev_restore,
295};
296
Alan Sterndb063502006-11-13 15:02:04 -0500297#else
298
299#define ksuspend_usb_init() 0
300#define ksuspend_usb_cleanup() do {} while (0)
Rafael J. Wysockiadf09492008-10-06 22:46:05 +0200301#define usb_device_pm_ops (*(struct dev_pm_ops *)0)
Alan Sterndb063502006-11-13 15:02:04 -0500302
303#endif /* CONFIG_PM */
Alan Stern645daaa2006-08-30 15:47:02 -0400304
Kay Sieversf7a386c2009-04-30 15:23:42 +0200305
Kay Sieverse454cea2009-09-18 23:01:12 +0200306static char *usb_devnode(struct device *dev, mode_t *mode)
Kay Sieversf7a386c2009-04-30 15:23:42 +0200307{
308 struct usb_device *usb_dev;
309
310 usb_dev = to_usb_device(dev);
311 return kasprintf(GFP_KERNEL, "bus/usb/%03d/%03d",
312 usb_dev->bus->busnum, usb_dev->devnum);
313}
314
Alan Sternf2189c42008-08-12 14:34:10 -0400315struct device_type usb_device_type = {
316 .name = "usb_device",
317 .release = usb_release_dev,
318 .uevent = usb_dev_uevent,
Kay Sieverse454cea2009-09-18 23:01:12 +0200319 .devnode = usb_devnode,
Alan Sternf2189c42008-08-12 14:34:10 -0400320 .pm = &usb_device_pm_ops,
321};
322
Inaky Perez-Gonzalezd7d07252007-07-31 20:34:00 -0700323
324/* Returns 1 if @usb_bus is WUSB, 0 otherwise */
325static unsigned usb_bus_is_wusb(struct usb_bus *bus)
326{
327 struct usb_hcd *hcd = container_of(bus, struct usb_hcd, self);
328 return hcd->wireless;
329}
330
331
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332/**
333 * usb_alloc_dev - usb device constructor (usbcore-internal)
334 * @parent: hub to which device is connected; null to allocate a root hub
335 * @bus: bus used to access the device
336 * @port1: one-based index of port; ignored for root hubs
Oliver Neukum92516442007-01-23 15:55:28 -0500337 * Context: !in_interrupt()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 *
339 * Only hub drivers (including virtual root hub drivers for host
340 * controllers) should ever call this.
341 *
342 * This call may not be used in a non-sleeping context.
343 */
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800344struct usb_device *usb_alloc_dev(struct usb_device *parent,
345 struct usb_bus *bus, unsigned port1)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346{
347 struct usb_device *dev;
Inaky Perez-Gonzalezd7d07252007-07-31 20:34:00 -0700348 struct usb_hcd *usb_hcd = container_of(bus, struct usb_hcd, self);
349 unsigned root_hub = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350
Alan Stern0a1ef3b2005-10-24 15:38:24 -0400351 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 if (!dev)
353 return NULL;
354
Alan Stern17200582006-08-30 11:32:52 -0400355 if (!usb_get_hcd(bus_to_hcd(bus))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 kfree(dev);
357 return NULL;
358 }
Sarah Sharpc6515272009-04-27 19:57:26 -0700359 /* Root hubs aren't true devices, so don't allocate HCD resources */
360 if (usb_hcd->driver->alloc_dev && parent &&
361 !usb_hcd->driver->alloc_dev(usb_hcd, dev)) {
362 usb_put_hcd(bus_to_hcd(bus));
363 kfree(dev);
364 return NULL;
365 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366
367 device_initialize(&dev->dev);
368 dev->dev.bus = &usb_bus_type;
Kay Sievers9f8b17e2007-03-13 15:59:31 +0100369 dev->dev.type = &usb_device_type;
Alan Stern2e5f10e2008-04-30 15:37:19 -0400370 dev->dev.groups = usb_device_groups;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 dev->dev.dma_mask = bus->controller->dma_mask;
Yinghai Lu70f458f2007-07-09 12:03:09 -0700372 set_dev_node(&dev->dev, dev_to_node(bus->controller));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373 dev->state = USB_STATE_ATTACHED;
Sarah Sharp4d59d8a2007-10-03 14:56:03 -0700374 atomic_set(&dev->urbnum, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375
376 INIT_LIST_HEAD(&dev->ep0.urb_list);
377 dev->ep0.desc.bLength = USB_DT_ENDPOINT_SIZE;
378 dev->ep0.desc.bDescriptorType = USB_DT_ENDPOINT;
379 /* ep0 maxpacket comes later, from device descriptor */
David Vrabel3444b262009-04-08 17:36:28 +0000380 usb_enable_endpoint(dev, &dev->ep0, false);
Alan Stern6840d252007-09-10 11:34:26 -0400381 dev->can_submit = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382
383 /* Save readable and stable topology id, distinguishing devices
384 * by location for diagnostics, tools, driver model, etc. The
385 * string is a path along hub ports, from the root. Each device's
386 * dev->devpath will be stable until USB is re-cabled, and hubs
Kay Sievers7071a3c2008-05-02 06:02:41 +0200387 * are often labeled with these port numbers. The name isn't
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 * as stable: bus->busnum changes easily from modprobe order,
389 * cardbus or pci hotplugging, and so on.
390 */
Oliver Neukum92516442007-01-23 15:55:28 -0500391 if (unlikely(!parent)) {
392 dev->devpath[0] = '0';
Sarah Sharp7206b002009-04-27 19:54:49 -0700393 dev->route = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394
395 dev->dev.parent = bus->controller;
Kay Sievers0031a062008-05-02 06:02:41 +0200396 dev_set_name(&dev->dev, "usb%d", bus->busnum);
Inaky Perez-Gonzalezd7d07252007-07-31 20:34:00 -0700397 root_hub = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 } else {
399 /* match any labeling on the hubs; it's one-based */
Sarah Sharp7206b002009-04-27 19:54:49 -0700400 if (parent->devpath[0] == '0') {
Oliver Neukum92516442007-01-23 15:55:28 -0500401 snprintf(dev->devpath, sizeof dev->devpath,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402 "%d", port1);
Sarah Sharp7206b002009-04-27 19:54:49 -0700403 /* Root ports are not counted in route string */
404 dev->route = 0;
405 } else {
Oliver Neukum92516442007-01-23 15:55:28 -0500406 snprintf(dev->devpath, sizeof dev->devpath,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 "%s.%d", parent->devpath, port1);
Sarah Sharp4a0cd962009-09-04 10:53:17 -0700408 /* Route string assumes hubs have less than 16 ports */
409 if (port1 < 15)
410 dev->route = parent->route +
411 (port1 << ((parent->level - 1)*4));
412 else
413 dev->route = parent->route +
414 (15 << ((parent->level - 1)*4));
Sarah Sharp7206b002009-04-27 19:54:49 -0700415 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416
417 dev->dev.parent = &parent->dev;
Kay Sievers0031a062008-05-02 06:02:41 +0200418 dev_set_name(&dev->dev, "%d-%s", bus->busnum, dev->devpath);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419
420 /* hub driver sets up TT records */
421 }
422
Alan Stern12c3da32005-11-23 12:09:52 -0500423 dev->portnum = port1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 dev->bus = bus;
425 dev->parent = parent;
426 INIT_LIST_HEAD(&dev->filelist);
427
Alan Stern645daaa2006-08-30 15:47:02 -0400428#ifdef CONFIG_PM
429 mutex_init(&dev->pm_mutex);
David Howellsc4028952006-11-22 14:57:56 +0000430 INIT_DELAYED_WORK(&dev->autosuspend, usb_autosuspend_work);
Alan Stern9ac39f22008-11-12 16:19:49 -0500431 INIT_WORK(&dev->autoresume, usb_autoresume_work);
Alan Sternb5e795f2007-02-20 15:00:53 -0500432 dev->autosuspend_delay = usb_autosuspend_delay * HZ;
Sarah Sharp15123002007-12-21 16:54:15 -0800433 dev->connect_time = jiffies;
434 dev->active_duration = -jiffies;
Alan Stern645daaa2006-08-30 15:47:02 -0400435#endif
Inaky Perez-Gonzalezd7d07252007-07-31 20:34:00 -0700436 if (root_hub) /* Root hub always ok [and always wired] */
437 dev->authorized = 1;
438 else {
439 dev->authorized = usb_hcd->authorized_default;
440 dev->wusb = usb_bus_is_wusb(bus)? 1 : 0;
441 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 return dev;
443}
444
445/**
446 * usb_get_dev - increments the reference count of the usb device structure
447 * @dev: the device being referenced
448 *
449 * Each live reference to a device should be refcounted.
450 *
451 * Drivers for USB interfaces should normally record such references in
452 * their probe() methods, when they bind to an interface, and release
453 * them by calling usb_put_dev(), in their disconnect() methods.
454 *
455 * A pointer to the device with the incremented reference counter is returned.
456 */
457struct usb_device *usb_get_dev(struct usb_device *dev)
458{
459 if (dev)
460 get_device(&dev->dev);
461 return dev;
462}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600463EXPORT_SYMBOL_GPL(usb_get_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464
465/**
466 * usb_put_dev - release a use of the usb device structure
467 * @dev: device that's been disconnected
468 *
469 * Must be called when a user of a device is finished with it. When the last
470 * user of the device calls this function, the memory of the device is freed.
471 */
472void usb_put_dev(struct usb_device *dev)
473{
474 if (dev)
475 put_device(&dev->dev);
476}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600477EXPORT_SYMBOL_GPL(usb_put_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478
479/**
480 * usb_get_intf - increments the reference count of the usb interface structure
481 * @intf: the interface being referenced
482 *
483 * Each live reference to a interface must be refcounted.
484 *
485 * Drivers for USB interfaces should normally record such references in
486 * their probe() methods, when they bind to an interface, and release
487 * them by calling usb_put_intf(), in their disconnect() methods.
488 *
489 * A pointer to the interface with the incremented reference counter is
490 * returned.
491 */
492struct usb_interface *usb_get_intf(struct usb_interface *intf)
493{
494 if (intf)
495 get_device(&intf->dev);
496 return intf;
497}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600498EXPORT_SYMBOL_GPL(usb_get_intf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499
500/**
501 * usb_put_intf - release a use of the usb interface structure
502 * @intf: interface that's been decremented
503 *
504 * Must be called when a user of an interface is finished with it. When the
505 * last user of the interface calls this function, the memory of the interface
506 * is freed.
507 */
508void usb_put_intf(struct usb_interface *intf)
509{
510 if (intf)
511 put_device(&intf->dev);
512}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600513EXPORT_SYMBOL_GPL(usb_put_intf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514
515/* USB device locking
516 *
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500517 * USB devices and interfaces are locked using the semaphore in their
518 * embedded struct device. The hub driver guarantees that whenever a
519 * device is connected or disconnected, drivers are called with the
520 * USB device locked as well as their particular interface.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521 *
522 * Complications arise when several devices are to be locked at the same
523 * time. Only hub-aware drivers that are part of usbcore ever have to
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500524 * do this; nobody else needs to worry about it. The rule for locking
525 * is simple:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 *
527 * When locking both a device and its parent, always lock the
528 * the parent first.
529 */
530
531/**
Randy Dunlapd0bcabc2008-02-29 22:03:07 -0800532 * usb_lock_device_for_reset - cautiously acquire the lock for a usb device structure
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533 * @udev: device that's being locked
534 * @iface: interface bound to the driver making the request (optional)
535 *
536 * Attempts to acquire the device lock, but fails if the device is
537 * NOTATTACHED or SUSPENDED, or if iface is specified and the interface
538 * is neither BINDING nor BOUND. Rather than sleeping to wait for the
539 * lock, the routine polls repeatedly. This is to prevent deadlock with
540 * disconnect; in some drivers (such as usb-storage) the disconnect()
Alan Stern3ea15962005-08-11 10:15:39 -0400541 * or suspend() method will block waiting for a device reset to complete.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 *
Alan Stern011b15d2008-11-04 11:29:27 -0500543 * Returns a negative error code for failure, otherwise 0.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 */
545int usb_lock_device_for_reset(struct usb_device *udev,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300546 const struct usb_interface *iface)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547{
Alan Stern3ea15962005-08-11 10:15:39 -0400548 unsigned long jiffies_expire = jiffies + HZ;
549
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 if (udev->state == USB_STATE_NOTATTACHED)
551 return -ENODEV;
552 if (udev->state == USB_STATE_SUSPENDED)
553 return -EHOSTUNREACH;
Alan Stern011b15d2008-11-04 11:29:27 -0500554 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
555 iface->condition == USB_INTERFACE_UNBOUND))
556 return -EINTR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500558 while (usb_trylock_device(udev) != 0) {
Alan Stern3ea15962005-08-11 10:15:39 -0400559
560 /* If we can't acquire the lock after waiting one second,
561 * we're probably deadlocked */
562 if (time_after(jiffies, jiffies_expire))
563 return -EBUSY;
564
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 msleep(15);
566 if (udev->state == USB_STATE_NOTATTACHED)
567 return -ENODEV;
568 if (udev->state == USB_STATE_SUSPENDED)
569 return -EHOSTUNREACH;
Alan Stern011b15d2008-11-04 11:29:27 -0500570 if (iface && (iface->condition == USB_INTERFACE_UNBINDING ||
571 iface->condition == USB_INTERFACE_UNBOUND))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 return -EINTR;
573 }
Alan Stern011b15d2008-11-04 11:29:27 -0500574 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600576EXPORT_SYMBOL_GPL(usb_lock_device_for_reset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577
578static struct usb_device *match_device(struct usb_device *dev,
579 u16 vendor_id, u16 product_id)
580{
581 struct usb_device *ret_dev = NULL;
582 int child;
583
584 dev_dbg(&dev->dev, "check for vendor %04x, product %04x ...\n",
585 le16_to_cpu(dev->descriptor.idVendor),
586 le16_to_cpu(dev->descriptor.idProduct));
587
588 /* see if this device matches */
589 if ((vendor_id == le16_to_cpu(dev->descriptor.idVendor)) &&
590 (product_id == le16_to_cpu(dev->descriptor.idProduct))) {
Oliver Neukum92516442007-01-23 15:55:28 -0500591 dev_dbg(&dev->dev, "matched this device!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592 ret_dev = usb_get_dev(dev);
593 goto exit;
594 }
595
596 /* look through all of the children of this device */
597 for (child = 0; child < dev->maxchild; ++child) {
598 if (dev->children[child]) {
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500599 usb_lock_device(dev->children[child]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 ret_dev = match_device(dev->children[child],
601 vendor_id, product_id);
Alan Stern9ad3d6c2005-11-17 17:10:32 -0500602 usb_unlock_device(dev->children[child]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 if (ret_dev)
604 goto exit;
605 }
606 }
607exit:
608 return ret_dev;
609}
610
611/**
612 * usb_find_device - find a specific usb device in the system
613 * @vendor_id: the vendor id of the device to find
614 * @product_id: the product id of the device to find
615 *
616 * Returns a pointer to a struct usb_device if such a specified usb
617 * device is present in the system currently. The usage count of the
618 * device will be incremented if a device is found. Make sure to call
619 * usb_put_dev() when the caller is finished with the device.
620 *
621 * If a device with the specified vendor and product id is not found,
622 * NULL is returned.
623 */
624struct usb_device *usb_find_device(u16 vendor_id, u16 product_id)
625{
626 struct list_head *buslist;
627 struct usb_bus *bus;
628 struct usb_device *dev = NULL;
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800629
Arjan van de Ven4186ecf2006-01-11 15:55:29 +0100630 mutex_lock(&usb_bus_list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 for (buslist = usb_bus_list.next;
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800632 buslist != &usb_bus_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 buslist = buslist->next) {
634 bus = container_of(buslist, struct usb_bus, bus_list);
635 if (!bus->root_hub)
636 continue;
637 usb_lock_device(bus->root_hub);
638 dev = match_device(bus->root_hub, vendor_id, product_id);
639 usb_unlock_device(bus->root_hub);
640 if (dev)
641 goto exit;
642 }
643exit:
Arjan van de Ven4186ecf2006-01-11 15:55:29 +0100644 mutex_unlock(&usb_bus_list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645 return dev;
646}
647
648/**
649 * usb_get_current_frame_number - return current bus frame number
650 * @dev: the device whose bus is being queried
651 *
652 * Returns the current frame number for the USB host controller
653 * used with the given USB device. This can be used when scheduling
654 * isochronous requests.
655 *
656 * Note that different kinds of host controller have different
657 * "scheduling horizons". While one type might support scheduling only
658 * 32 frames into the future, others could support scheduling up to
659 * 1024 frames into the future.
660 */
661int usb_get_current_frame_number(struct usb_device *dev)
662{
Oliver Neukum92516442007-01-23 15:55:28 -0500663 return usb_hcd_get_frame_number(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600665EXPORT_SYMBOL_GPL(usb_get_current_frame_number);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666
667/*-------------------------------------------------------------------*/
668/*
669 * __usb_get_extra_descriptor() finds a descriptor of specific type in the
670 * extra field of the interface and endpoint descriptor structs.
671 */
672
673int __usb_get_extra_descriptor(char *buffer, unsigned size,
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800674 unsigned char type, void **ptr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675{
676 struct usb_descriptor_header *header;
677
678 while (size >= sizeof(struct usb_descriptor_header)) {
679 header = (struct usb_descriptor_header *)buffer;
680
681 if (header->bLength < 2) {
682 printk(KERN_ERR
683 "%s: bogus descriptor, type %d length %d\n",
684 usbcore_name,
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800685 header->bDescriptorType,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 header->bLength);
687 return -1;
688 }
689
690 if (header->bDescriptorType == type) {
691 *ptr = header;
692 return 0;
693 }
694
695 buffer += header->bLength;
696 size -= header->bLength;
697 }
698 return -1;
699}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600700EXPORT_SYMBOL_GPL(__usb_get_extra_descriptor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701
702/**
703 * usb_buffer_alloc - allocate dma-consistent buffer for URB_NO_xxx_DMA_MAP
704 * @dev: device the buffer will be used with
705 * @size: requested buffer size
706 * @mem_flags: affect whether allocation may block
707 * @dma: used to return DMA address of buffer
708 *
709 * Return value is either null (indicating no buffer could be allocated), or
710 * the cpu-space pointer to a buffer that may be used to perform DMA to the
711 * specified device. Such cpu-space buffers are returned along with the DMA
712 * address (through the pointer provided).
713 *
714 * These buffers are used with URB_NO_xxx_DMA_MAP set in urb->transfer_flags
David Brownellfbf54dd2007-07-01 23:33:12 -0700715 * to avoid behaviors like using "DMA bounce buffers", or thrashing IOMMU
716 * hardware during URB completion/resubmit. The implementation varies between
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717 * platforms, depending on details of how DMA will work to this device.
David Brownellfbf54dd2007-07-01 23:33:12 -0700718 * Using these buffers also eliminates cacheline sharing problems on
719 * architectures where CPU caches are not DMA-coherent. On systems without
720 * bus-snooping caches, these buffers are uncached.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721 *
722 * When the buffer is no longer used, free it with usb_buffer_free().
723 */
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800724void *usb_buffer_alloc(struct usb_device *dev, size_t size, gfp_t mem_flags,
725 dma_addr_t *dma)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726{
Alan Sterna6d2bb92006-08-30 11:27:36 -0400727 if (!dev || !dev->bus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 return NULL;
Oliver Neukum92516442007-01-23 15:55:28 -0500729 return hcd_buffer_alloc(dev->bus, size, mem_flags, dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600731EXPORT_SYMBOL_GPL(usb_buffer_alloc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732
733/**
734 * usb_buffer_free - free memory allocated with usb_buffer_alloc()
735 * @dev: device the buffer was used with
736 * @size: requested buffer size
737 * @addr: CPU address of buffer
738 * @dma: DMA address of buffer
739 *
740 * This reclaims an I/O buffer, letting it be reused. The memory must have
741 * been allocated using usb_buffer_alloc(), and the parameters must match
David Brownellfbf54dd2007-07-01 23:33:12 -0700742 * those provided in that allocation request.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 */
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800744void usb_buffer_free(struct usb_device *dev, size_t size, void *addr,
745 dma_addr_t dma)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746{
Alan Sterna6d2bb92006-08-30 11:27:36 -0400747 if (!dev || !dev->bus)
Dmitry Torokhovb94badb2006-08-01 22:33:34 -0400748 return;
749 if (!addr)
750 return;
Oliver Neukum92516442007-01-23 15:55:28 -0500751 hcd_buffer_free(dev->bus, size, addr, dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600753EXPORT_SYMBOL_GPL(usb_buffer_free);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754
755/**
756 * usb_buffer_map - create DMA mapping(s) for an urb
757 * @urb: urb whose transfer_buffer/setup_packet will be mapped
758 *
759 * Return value is either null (indicating no buffer could be mapped), or
760 * the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are
761 * added to urb->transfer_flags if the operation succeeds. If the device
762 * is connected to this system through a non-DMA controller, this operation
763 * always succeeds.
764 *
765 * This call would normally be used for an urb which is reused, perhaps
766 * as the target of a large periodic transfer, with usb_buffer_dmasync()
767 * calls to synchronize memory and dma state.
768 *
769 * Reverse the effect of this call with usb_buffer_unmap().
770 */
771#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500772struct urb *usb_buffer_map(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700773{
774 struct usb_bus *bus;
775 struct device *controller;
776
777 if (!urb
778 || !urb->dev
779 || !(bus = urb->dev->bus)
780 || !(controller = bus->controller))
781 return NULL;
782
783 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500784 urb->transfer_dma = dma_map_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 urb->transfer_buffer, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500786 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500788 if (usb_pipecontrol(urb->pipe))
789 urb->setup_dma = dma_map_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 urb->setup_packet,
Oliver Neukum92516442007-01-23 15:55:28 -0500791 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792 DMA_TO_DEVICE);
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800793 /* FIXME generic api broken like pci, can't report errors */
794 /* if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795 } else
796 urb->transfer_dma = ~0;
797 urb->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP
798 | URB_NO_SETUP_DMA_MAP);
799 return urb;
800}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600801EXPORT_SYMBOL_GPL(usb_buffer_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802#endif /* 0 */
803
804/* XXX DISABLED, no users currently. If you wish to re-enable this
805 * XXX please determine whether the sync is to transfer ownership of
806 * XXX the buffer from device to cpu or vice verse, and thusly use the
807 * XXX appropriate _for_{cpu,device}() method. -DaveM
808 */
809#if 0
810
811/**
812 * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
813 * @urb: urb whose transfer_buffer/setup_packet will be synchronized
814 */
Oliver Neukum92516442007-01-23 15:55:28 -0500815void usb_buffer_dmasync(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816{
817 struct usb_bus *bus;
818 struct device *controller;
819
820 if (!urb
821 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
822 || !urb->dev
823 || !(bus = urb->dev->bus)
824 || !(controller = bus->controller))
825 return;
826
827 if (controller->dma_mask) {
FUJITA Tomonori9b8e7ba2009-05-28 10:10:44 +0900828 dma_sync_single_for_cpu(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829 urb->transfer_dma, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500830 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500832 if (usb_pipecontrol(urb->pipe))
FUJITA Tomonori9b8e7ba2009-05-28 10:10:44 +0900833 dma_sync_single_for_cpu(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 urb->setup_dma,
Oliver Neukum92516442007-01-23 15:55:28 -0500835 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836 DMA_TO_DEVICE);
837 }
838}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600839EXPORT_SYMBOL_GPL(usb_buffer_dmasync);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840#endif
841
842/**
843 * usb_buffer_unmap - free DMA mapping(s) for an urb
844 * @urb: urb whose transfer_buffer will be unmapped
845 *
846 * Reverses the effect of usb_buffer_map().
847 */
848#if 0
Oliver Neukum92516442007-01-23 15:55:28 -0500849void usb_buffer_unmap(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850{
851 struct usb_bus *bus;
852 struct device *controller;
853
854 if (!urb
855 || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
856 || !urb->dev
857 || !(bus = urb->dev->bus)
858 || !(controller = bus->controller))
859 return;
860
861 if (controller->dma_mask) {
Oliver Neukum92516442007-01-23 15:55:28 -0500862 dma_unmap_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863 urb->transfer_dma, urb->transfer_buffer_length,
Oliver Neukum92516442007-01-23 15:55:28 -0500864 usb_pipein(urb->pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865 ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Oliver Neukum92516442007-01-23 15:55:28 -0500866 if (usb_pipecontrol(urb->pipe))
867 dma_unmap_single(controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 urb->setup_dma,
Oliver Neukum92516442007-01-23 15:55:28 -0500869 sizeof(struct usb_ctrlrequest),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 DMA_TO_DEVICE);
871 }
872 urb->transfer_flags &= ~(URB_NO_TRANSFER_DMA_MAP
873 | URB_NO_SETUP_DMA_MAP);
874}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600875EXPORT_SYMBOL_GPL(usb_buffer_unmap);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876#endif /* 0 */
877
878/**
879 * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
880 * @dev: device to which the scatterlist will be mapped
Alan Stern5e60a162007-07-30 17:07:21 -0400881 * @is_in: mapping transfer direction
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882 * @sg: the scatterlist to map
883 * @nents: the number of entries in the scatterlist
884 *
885 * Return value is either < 0 (indicating no buffers could be mapped), or
886 * the number of DMA mapping array entries in the scatterlist.
887 *
888 * The caller is responsible for placing the resulting DMA addresses from
889 * the scatterlist into URB transfer buffer pointers, and for setting the
890 * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
891 *
892 * Top I/O rates come from queuing URBs, instead of waiting for each one
893 * to complete before starting the next I/O. This is particularly easy
894 * to do with scatterlists. Just allocate and submit one URB for each DMA
895 * mapping entry returned, stopping on the first error or when all succeed.
896 * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
897 *
898 * This call would normally be used when translating scatterlist requests,
899 * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
900 * may be able to coalesce mappings for improved I/O efficiency.
901 *
902 * Reverse the effect of this call with usb_buffer_unmap_sg().
903 */
Alan Stern5e60a162007-07-30 17:07:21 -0400904int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300905 struct scatterlist *sg, int nents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906{
907 struct usb_bus *bus;
908 struct device *controller;
909
910 if (!dev
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911 || !(bus = dev->bus)
912 || !(controller = bus->controller)
913 || !controller->dma_mask)
Jiri Slaby29122822009-08-22 20:24:49 +0200914 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -0800916 /* FIXME generic api broken like pci, can't report errors */
Oliver Neukum92516442007-01-23 15:55:28 -0500917 return dma_map_sg(controller, sg, nents,
Jiri Slaby29122822009-08-22 20:24:49 +0200918 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE) ? : -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600920EXPORT_SYMBOL_GPL(usb_buffer_map_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921
922/* XXX DISABLED, no users currently. If you wish to re-enable this
923 * XXX please determine whether the sync is to transfer ownership of
924 * XXX the buffer from device to cpu or vice verse, and thusly use the
925 * XXX appropriate _for_{cpu,device}() method. -DaveM
926 */
927#if 0
928
929/**
930 * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
931 * @dev: device to which the scatterlist will be mapped
Alan Stern5e60a162007-07-30 17:07:21 -0400932 * @is_in: mapping transfer direction
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933 * @sg: the scatterlist to synchronize
934 * @n_hw_ents: the positive return value from usb_buffer_map_sg
935 *
936 * Use this when you are re-using a scatterlist's data buffers for
937 * another USB request.
938 */
Alan Stern5e60a162007-07-30 17:07:21 -0400939void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300940 struct scatterlist *sg, int n_hw_ents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700941{
942 struct usb_bus *bus;
943 struct device *controller;
944
945 if (!dev
946 || !(bus = dev->bus)
947 || !(controller = bus->controller)
948 || !controller->dma_mask)
949 return;
950
FUJITA Tomonori9b8e7ba2009-05-28 10:10:44 +0900951 dma_sync_sg_for_cpu(controller, sg, n_hw_ents,
952 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700953}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600954EXPORT_SYMBOL_GPL(usb_buffer_dmasync_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955#endif
956
957/**
958 * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
959 * @dev: device to which the scatterlist will be mapped
Alan Stern5e60a162007-07-30 17:07:21 -0400960 * @is_in: mapping transfer direction
Linus Torvalds1da177e2005-04-16 15:20:36 -0700961 * @sg: the scatterlist to unmap
962 * @n_hw_ents: the positive return value from usb_buffer_map_sg
963 *
964 * Reverses the effect of usb_buffer_map_sg().
965 */
Alan Stern5e60a162007-07-30 17:07:21 -0400966void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
Luiz Fernando N. Capitulino095bc332006-08-26 23:48:11 -0300967 struct scatterlist *sg, int n_hw_ents)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968{
969 struct usb_bus *bus;
970 struct device *controller;
971
972 if (!dev
973 || !(bus = dev->bus)
974 || !(controller = bus->controller)
975 || !controller->dma_mask)
976 return;
977
Oliver Neukum92516442007-01-23 15:55:28 -0500978 dma_unmap_sg(controller, sg, n_hw_ents,
Alan Stern5e60a162007-07-30 17:07:21 -0400979 is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600981EXPORT_SYMBOL_GPL(usb_buffer_unmap_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700982
Rusty Russell785895f2008-11-22 13:01:06 +1030983/* To disable USB, kernel command line is 'nousb' not 'usbcore.nousb' */
984#ifdef MODULE
985module_param(nousb, bool, 0444);
986#else
987core_param(nousb, nousb, bool, 0444);
988#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989
990/*
991 * for external read access to <nousb>
992 */
993int usb_disabled(void)
994{
995 return nousb;
996}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600997EXPORT_SYMBOL_GPL(usb_disabled);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998
999/*
Alan Stern3b23dd62008-12-05 14:10:34 -05001000 * Notifications of device and interface registration
1001 */
1002static int usb_bus_notify(struct notifier_block *nb, unsigned long action,
1003 void *data)
1004{
1005 struct device *dev = data;
1006
1007 switch (action) {
1008 case BUS_NOTIFY_ADD_DEVICE:
1009 if (dev->type == &usb_device_type)
1010 (void) usb_create_sysfs_dev_files(to_usb_device(dev));
1011 else if (dev->type == &usb_if_device_type)
1012 (void) usb_create_sysfs_intf_files(
1013 to_usb_interface(dev));
1014 break;
1015
1016 case BUS_NOTIFY_DEL_DEVICE:
1017 if (dev->type == &usb_device_type)
1018 usb_remove_sysfs_dev_files(to_usb_device(dev));
1019 else if (dev->type == &usb_if_device_type)
1020 usb_remove_sysfs_intf_files(to_usb_interface(dev));
1021 break;
1022 }
1023 return 0;
1024}
1025
1026static struct notifier_block usb_bus_nb = {
1027 .notifier_call = usb_bus_notify,
1028};
1029
Greg Kroah-Hartman00048b82009-04-24 14:56:26 -07001030struct dentry *usb_debug_root;
1031EXPORT_SYMBOL_GPL(usb_debug_root);
1032
Greg Kroah-Hartman97d7b7a2009-04-24 15:16:04 -07001033struct dentry *usb_debug_devices;
1034
Greg Kroah-Hartman00048b82009-04-24 14:56:26 -07001035static int usb_debugfs_init(void)
1036{
1037 usb_debug_root = debugfs_create_dir("usb", NULL);
1038 if (!usb_debug_root)
1039 return -ENOENT;
Greg Kroah-Hartman97d7b7a2009-04-24 15:16:04 -07001040
1041 usb_debug_devices = debugfs_create_file("devices", 0444,
1042 usb_debug_root, NULL,
1043 &usbfs_devices_fops);
1044 if (!usb_debug_devices) {
1045 debugfs_remove(usb_debug_root);
1046 usb_debug_root = NULL;
1047 return -ENOENT;
1048 }
1049
Greg Kroah-Hartman00048b82009-04-24 14:56:26 -07001050 return 0;
1051}
1052
1053static void usb_debugfs_cleanup(void)
1054{
Greg Kroah-Hartman97d7b7a2009-04-24 15:16:04 -07001055 debugfs_remove(usb_debug_devices);
Greg Kroah-Hartman00048b82009-04-24 14:56:26 -07001056 debugfs_remove(usb_debug_root);
1057}
1058
Alan Stern3b23dd62008-12-05 14:10:34 -05001059/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060 * Init
1061 */
1062static int __init usb_init(void)
1063{
1064 int retval;
1065 if (nousb) {
Oliver Neukum92516442007-01-23 15:55:28 -05001066 pr_info("%s: USB support disabled\n", usbcore_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067 return 0;
1068 }
1069
Greg Kroah-Hartman00048b82009-04-24 14:56:26 -07001070 retval = usb_debugfs_init();
1071 if (retval)
1072 goto out;
1073
Alan Sternbd859282006-09-19 10:14:07 -04001074 retval = ksuspend_usb_init();
1075 if (retval)
1076 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001077 retval = bus_register(&usb_bus_type);
Greg Kroah-Hartman2c044a42008-01-30 15:21:33 -08001078 if (retval)
Alan Sternbd859282006-09-19 10:14:07 -04001079 goto bus_register_failed;
Alan Stern3b23dd62008-12-05 14:10:34 -05001080 retval = bus_register_notifier(&usb_bus_type, &usb_bus_nb);
1081 if (retval)
1082 goto bus_notifier_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001083 retval = usb_major_init();
1084 if (retval)
1085 goto major_init_failed;
Kay Sieversfbf82fd2005-07-31 01:05:53 +02001086 retval = usb_register(&usbfs_driver);
1087 if (retval)
1088 goto driver_register_failed;
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001089 retval = usb_devio_init();
Kay Sieversfbf82fd2005-07-31 01:05:53 +02001090 if (retval)
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001091 goto usb_devio_init_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092 retval = usbfs_init();
1093 if (retval)
1094 goto fs_init_failed;
1095 retval = usb_hub_init();
1096 if (retval)
1097 goto hub_init_failed;
Alan Stern8bb54ab2006-07-01 22:08:49 -04001098 retval = usb_register_device_driver(&usb_generic_driver, THIS_MODULE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099 if (!retval)
1100 goto out;
1101
1102 usb_hub_cleanup();
1103hub_init_failed:
1104 usbfs_cleanup();
1105fs_init_failed:
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001106 usb_devio_cleanup();
1107usb_devio_init_failed:
Kay Sieversfbf82fd2005-07-31 01:05:53 +02001108 usb_deregister(&usbfs_driver);
1109driver_register_failed:
1110 usb_major_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001111major_init_failed:
Alan Stern3b23dd62008-12-05 14:10:34 -05001112 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
1113bus_notifier_failed:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001114 bus_unregister(&usb_bus_type);
Alan Sternbd859282006-09-19 10:14:07 -04001115bus_register_failed:
1116 ksuspend_usb_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117out:
1118 return retval;
1119}
1120
1121/*
1122 * Cleanup
1123 */
1124static void __exit usb_exit(void)
1125{
1126 /* This will matter if shutdown/reboot does exitcalls. */
1127 if (nousb)
1128 return;
1129
Alan Stern8bb54ab2006-07-01 22:08:49 -04001130 usb_deregister_device_driver(&usb_generic_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131 usb_major_cleanup();
1132 usbfs_cleanup();
Kay Sieversfbf82fd2005-07-31 01:05:53 +02001133 usb_deregister(&usbfs_driver);
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001134 usb_devio_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135 usb_hub_cleanup();
Alan Stern3b23dd62008-12-05 14:10:34 -05001136 bus_unregister_notifier(&usb_bus_type, &usb_bus_nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137 bus_unregister(&usb_bus_type);
Alan Sternbd859282006-09-19 10:14:07 -04001138 ksuspend_usb_cleanup();
Greg Kroah-Hartman00048b82009-04-24 14:56:26 -07001139 usb_debugfs_cleanup();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140}
1141
1142subsys_initcall(usb_init);
1143module_exit(usb_exit);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001144MODULE_LICENSE("GPL");