xref: /linux-6.15/include/linux/usb.h (revision 5d4a2e29)
1 #ifndef __LINUX_USB_H
2 #define __LINUX_USB_H
3 
4 #include <linux/mod_devicetable.h>
5 #include <linux/usb/ch9.h>
6 
7 #define USB_MAJOR			180
8 #define USB_DEVICE_MAJOR		189
9 
10 
11 #ifdef __KERNEL__
12 
13 #include <linux/errno.h>        /* for -ENODEV */
14 #include <linux/delay.h>	/* for mdelay() */
15 #include <linux/interrupt.h>	/* for in_interrupt() */
16 #include <linux/list.h>		/* for struct list_head */
17 #include <linux/kref.h>		/* for struct kref */
18 #include <linux/device.h>	/* for struct device */
19 #include <linux/fs.h>		/* for struct file_operations */
20 #include <linux/completion.h>	/* for struct completion */
21 #include <linux/sched.h>	/* for current && schedule_timeout */
22 #include <linux/mutex.h>	/* for struct mutex */
23 
24 struct usb_device;
25 struct usb_driver;
26 struct wusb_dev;
27 
28 /*-------------------------------------------------------------------------*/
29 
30 /*
31  * Host-side wrappers for standard USB descriptors ... these are parsed
32  * from the data provided by devices.  Parsing turns them from a flat
33  * sequence of descriptors into a hierarchy:
34  *
35  *  - devices have one (usually) or more configs;
36  *  - configs have one (often) or more interfaces;
37  *  - interfaces have one (usually) or more settings;
38  *  - each interface setting has zero or (usually) more endpoints.
39  *  - a SuperSpeed endpoint has a companion descriptor
40  *
41  * And there might be other descriptors mixed in with those.
42  *
43  * Devices may also have class-specific or vendor-specific descriptors.
44  */
45 
46 struct ep_device;
47 
48 /**
49  * struct usb_host_endpoint - host-side endpoint descriptor and queue
50  * @desc: descriptor for this endpoint, wMaxPacketSize in native byteorder
51  * @ss_ep_comp: SuperSpeed companion descriptor for this endpoint
52  * @urb_list: urbs queued to this endpoint; maintained by usbcore
53  * @hcpriv: for use by HCD; typically holds hardware dma queue head (QH)
54  *	with one or more transfer descriptors (TDs) per urb
55  * @ep_dev: ep_device for sysfs info
56  * @extra: descriptors following this endpoint in the configuration
57  * @extralen: how many bytes of "extra" are valid
58  * @enabled: URBs may be submitted to this endpoint
59  *
60  * USB requests are always queued to a given endpoint, identified by a
61  * descriptor within an active interface in a given USB configuration.
62  */
63 struct usb_host_endpoint {
64 	struct usb_endpoint_descriptor		desc;
65 	struct usb_ss_ep_comp_descriptor	ss_ep_comp;
66 	struct list_head		urb_list;
67 	void				*hcpriv;
68 	struct ep_device		*ep_dev;	/* For sysfs info */
69 
70 	unsigned char *extra;   /* Extra descriptors */
71 	int extralen;
72 	int enabled;
73 };
74 
75 /* host-side wrapper for one interface setting's parsed descriptors */
76 struct usb_host_interface {
77 	struct usb_interface_descriptor	desc;
78 
79 	/* array of desc.bNumEndpoint endpoints associated with this
80 	 * interface setting.  these will be in no particular order.
81 	 */
82 	struct usb_host_endpoint *endpoint;
83 
84 	char *string;		/* iInterface string, if present */
85 	unsigned char *extra;   /* Extra descriptors */
86 	int extralen;
87 };
88 
89 enum usb_interface_condition {
90 	USB_INTERFACE_UNBOUND = 0,
91 	USB_INTERFACE_BINDING,
92 	USB_INTERFACE_BOUND,
93 	USB_INTERFACE_UNBINDING,
94 };
95 
96 /**
97  * struct usb_interface - what usb device drivers talk to
98  * @altsetting: array of interface structures, one for each alternate
99  *	setting that may be selected.  Each one includes a set of
100  *	endpoint configurations.  They will be in no particular order.
101  * @cur_altsetting: the current altsetting.
102  * @num_altsetting: number of altsettings defined.
103  * @intf_assoc: interface association descriptor
104  * @minor: the minor number assigned to this interface, if this
105  *	interface is bound to a driver that uses the USB major number.
106  *	If this interface does not use the USB major, this field should
107  *	be unused.  The driver should set this value in the probe()
108  *	function of the driver, after it has been assigned a minor
109  *	number from the USB core by calling usb_register_dev().
110  * @condition: binding state of the interface: not bound, binding
111  *	(in probe()), bound to a driver, or unbinding (in disconnect())
112  * @sysfs_files_created: sysfs attributes exist
113  * @ep_devs_created: endpoint child pseudo-devices exist
114  * @unregistering: flag set when the interface is being unregistered
115  * @needs_remote_wakeup: flag set when the driver requires remote-wakeup
116  *	capability during autosuspend.
117  * @needs_altsetting0: flag set when a set-interface request for altsetting 0
118  *	has been deferred.
119  * @needs_binding: flag set when the driver should be re-probed or unbound
120  *	following a reset or suspend operation it doesn't support.
121  * @dev: driver model's view of this device
122  * @usb_dev: if an interface is bound to the USB major, this will point
123  *	to the sysfs representation for that device.
124  * @pm_usage_cnt: PM usage counter for this interface
125  * @reset_ws: Used for scheduling resets from atomic context.
126  * @reset_running: set to 1 if the interface is currently running a
127  *      queued reset so that usb_cancel_queued_reset() doesn't try to
128  *      remove from the workqueue when running inside the worker
129  *      thread. See __usb_queue_reset_device().
130  *
131  * USB device drivers attach to interfaces on a physical device.  Each
132  * interface encapsulates a single high level function, such as feeding
133  * an audio stream to a speaker or reporting a change in a volume control.
134  * Many USB devices only have one interface.  The protocol used to talk to
135  * an interface's endpoints can be defined in a usb "class" specification,
136  * or by a product's vendor.  The (default) control endpoint is part of
137  * every interface, but is never listed among the interface's descriptors.
138  *
139  * The driver that is bound to the interface can use standard driver model
140  * calls such as dev_get_drvdata() on the dev member of this structure.
141  *
142  * Each interface may have alternate settings.  The initial configuration
143  * of a device sets altsetting 0, but the device driver can change
144  * that setting using usb_set_interface().  Alternate settings are often
145  * used to control the use of periodic endpoints, such as by having
146  * different endpoints use different amounts of reserved USB bandwidth.
147  * All standards-conformant USB devices that use isochronous endpoints
148  * will use them in non-default settings.
149  *
150  * The USB specification says that alternate setting numbers must run from
151  * 0 to one less than the total number of alternate settings.  But some
152  * devices manage to mess this up, and the structures aren't necessarily
153  * stored in numerical order anyhow.  Use usb_altnum_to_altsetting() to
154  * look up an alternate setting in the altsetting array based on its number.
155  */
156 struct usb_interface {
157 	/* array of alternate settings for this interface,
158 	 * stored in no particular order */
159 	struct usb_host_interface *altsetting;
160 
161 	struct usb_host_interface *cur_altsetting;	/* the currently
162 					 * active alternate setting */
163 	unsigned num_altsetting;	/* number of alternate settings */
164 
165 	/* If there is an interface association descriptor then it will list
166 	 * the associated interfaces */
167 	struct usb_interface_assoc_descriptor *intf_assoc;
168 
169 	int minor;			/* minor number this interface is
170 					 * bound to */
171 	enum usb_interface_condition condition;		/* state of binding */
172 	unsigned sysfs_files_created:1;	/* the sysfs attributes exist */
173 	unsigned ep_devs_created:1;	/* endpoint "devices" exist */
174 	unsigned unregistering:1;	/* unregistration is in progress */
175 	unsigned needs_remote_wakeup:1;	/* driver requires remote wakeup */
176 	unsigned needs_altsetting0:1;	/* switch to altsetting 0 is pending */
177 	unsigned needs_binding:1;	/* needs delayed unbind/rebind */
178 	unsigned reset_running:1;
179 	unsigned resetting_device:1;	/* true: bandwidth alloc after reset */
180 
181 	struct device dev;		/* interface specific device info */
182 	struct device *usb_dev;
183 	atomic_t pm_usage_cnt;		/* usage counter for autosuspend */
184 	struct work_struct reset_ws;	/* for resets in atomic context */
185 };
186 #define	to_usb_interface(d) container_of(d, struct usb_interface, dev)
187 
188 static inline void *usb_get_intfdata(struct usb_interface *intf)
189 {
190 	return dev_get_drvdata(&intf->dev);
191 }
192 
193 static inline void usb_set_intfdata(struct usb_interface *intf, void *data)
194 {
195 	dev_set_drvdata(&intf->dev, data);
196 }
197 
198 struct usb_interface *usb_get_intf(struct usb_interface *intf);
199 void usb_put_intf(struct usb_interface *intf);
200 
201 /* this maximum is arbitrary */
202 #define USB_MAXINTERFACES	32
203 #define USB_MAXIADS		(USB_MAXINTERFACES/2)
204 
205 /**
206  * struct usb_interface_cache - long-term representation of a device interface
207  * @num_altsetting: number of altsettings defined.
208  * @ref: reference counter.
209  * @altsetting: variable-length array of interface structures, one for
210  *	each alternate setting that may be selected.  Each one includes a
211  *	set of endpoint configurations.  They will be in no particular order.
212  *
213  * These structures persist for the lifetime of a usb_device, unlike
214  * struct usb_interface (which persists only as long as its configuration
215  * is installed).  The altsetting arrays can be accessed through these
216  * structures at any time, permitting comparison of configurations and
217  * providing support for the /proc/bus/usb/devices pseudo-file.
218  */
219 struct usb_interface_cache {
220 	unsigned num_altsetting;	/* number of alternate settings */
221 	struct kref ref;		/* reference counter */
222 
223 	/* variable-length array of alternate settings for this interface,
224 	 * stored in no particular order */
225 	struct usb_host_interface altsetting[0];
226 };
227 #define	ref_to_usb_interface_cache(r) \
228 		container_of(r, struct usb_interface_cache, ref)
229 #define	altsetting_to_usb_interface_cache(a) \
230 		container_of(a, struct usb_interface_cache, altsetting[0])
231 
232 /**
233  * struct usb_host_config - representation of a device's configuration
234  * @desc: the device's configuration descriptor.
235  * @string: pointer to the cached version of the iConfiguration string, if
236  *	present for this configuration.
237  * @intf_assoc: list of any interface association descriptors in this config
238  * @interface: array of pointers to usb_interface structures, one for each
239  *	interface in the configuration.  The number of interfaces is stored
240  *	in desc.bNumInterfaces.  These pointers are valid only while the
241  *	the configuration is active.
242  * @intf_cache: array of pointers to usb_interface_cache structures, one
243  *	for each interface in the configuration.  These structures exist
244  *	for the entire life of the device.
245  * @extra: pointer to buffer containing all extra descriptors associated
246  *	with this configuration (those preceding the first interface
247  *	descriptor).
248  * @extralen: length of the extra descriptors buffer.
249  *
250  * USB devices may have multiple configurations, but only one can be active
251  * at any time.  Each encapsulates a different operational environment;
252  * for example, a dual-speed device would have separate configurations for
253  * full-speed and high-speed operation.  The number of configurations
254  * available is stored in the device descriptor as bNumConfigurations.
255  *
256  * A configuration can contain multiple interfaces.  Each corresponds to
257  * a different function of the USB device, and all are available whenever
258  * the configuration is active.  The USB standard says that interfaces
259  * are supposed to be numbered from 0 to desc.bNumInterfaces-1, but a lot
260  * of devices get this wrong.  In addition, the interface array is not
261  * guaranteed to be sorted in numerical order.  Use usb_ifnum_to_if() to
262  * look up an interface entry based on its number.
263  *
264  * Device drivers should not attempt to activate configurations.  The choice
265  * of which configuration to install is a policy decision based on such
266  * considerations as available power, functionality provided, and the user's
267  * desires (expressed through userspace tools).  However, drivers can call
268  * usb_reset_configuration() to reinitialize the current configuration and
269  * all its interfaces.
270  */
271 struct usb_host_config {
272 	struct usb_config_descriptor	desc;
273 
274 	char *string;		/* iConfiguration string, if present */
275 
276 	/* List of any Interface Association Descriptors in this
277 	 * configuration. */
278 	struct usb_interface_assoc_descriptor *intf_assoc[USB_MAXIADS];
279 
280 	/* the interfaces associated with this configuration,
281 	 * stored in no particular order */
282 	struct usb_interface *interface[USB_MAXINTERFACES];
283 
284 	/* Interface information available even when this is not the
285 	 * active configuration */
286 	struct usb_interface_cache *intf_cache[USB_MAXINTERFACES];
287 
288 	unsigned char *extra;   /* Extra descriptors */
289 	int extralen;
290 };
291 
292 int __usb_get_extra_descriptor(char *buffer, unsigned size,
293 	unsigned char type, void **ptr);
294 #define usb_get_extra_descriptor(ifpoint, type, ptr) \
295 				__usb_get_extra_descriptor((ifpoint)->extra, \
296 				(ifpoint)->extralen, \
297 				type, (void **)ptr)
298 
299 /* ----------------------------------------------------------------------- */
300 
301 /* USB device number allocation bitmap */
302 struct usb_devmap {
303 	unsigned long devicemap[128 / (8*sizeof(unsigned long))];
304 };
305 
306 /*
307  * Allocated per bus (tree of devices) we have:
308  */
309 struct usb_bus {
310 	struct device *controller;	/* host/master side hardware */
311 	int busnum;			/* Bus number (in order of reg) */
312 	const char *bus_name;		/* stable id (PCI slot_name etc) */
313 	u8 uses_dma;			/* Does the host controller use DMA? */
314 	u8 otg_port;			/* 0, or number of OTG/HNP port */
315 	unsigned is_b_host:1;		/* true during some HNP roleswitches */
316 	unsigned b_hnp_enable:1;	/* OTG: did A-Host enable HNP? */
317 	unsigned sg_tablesize;		/* 0 or largest number of sg list entries */
318 
319 	int devnum_next;		/* Next open device number in
320 					 * round-robin allocation */
321 
322 	struct usb_devmap devmap;	/* device address allocation map */
323 	struct usb_device *root_hub;	/* Root hub */
324 	struct usb_bus *hs_companion;	/* Companion EHCI bus, if any */
325 	struct list_head bus_list;	/* list of busses */
326 
327 	int bandwidth_allocated;	/* on this bus: how much of the time
328 					 * reserved for periodic (intr/iso)
329 					 * requests is used, on average?
330 					 * Units: microseconds/frame.
331 					 * Limits: Full/low speed reserve 90%,
332 					 * while high speed reserves 80%.
333 					 */
334 	int bandwidth_int_reqs;		/* number of Interrupt requests */
335 	int bandwidth_isoc_reqs;	/* number of Isoc. requests */
336 
337 #ifdef CONFIG_USB_DEVICEFS
338 	struct dentry *usbfs_dentry;	/* usbfs dentry entry for the bus */
339 #endif
340 
341 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
342 	struct mon_bus *mon_bus;	/* non-null when associated */
343 	int monitored;			/* non-zero when monitored */
344 #endif
345 };
346 
347 /* ----------------------------------------------------------------------- */
348 
349 /* This is arbitrary.
350  * From USB 2.0 spec Table 11-13, offset 7, a hub can
351  * have up to 255 ports. The most yet reported is 10.
352  *
353  * Current Wireless USB host hardware (Intel i1480 for example) allows
354  * up to 22 devices to connect. Upcoming hardware might raise that
355  * limit. Because the arrays need to add a bit for hub status data, we
356  * do 31, so plus one evens out to four bytes.
357  */
358 #define USB_MAXCHILDREN		(31)
359 
360 struct usb_tt;
361 
362 /**
363  * struct usb_device - kernel's representation of a USB device
364  * @devnum: device number; address on a USB bus
365  * @devpath: device ID string for use in messages (e.g., /port/...)
366  * @route: tree topology hex string for use with xHCI
367  * @state: device state: configured, not attached, etc.
368  * @speed: device speed: high/full/low (or error)
369  * @tt: Transaction Translator info; used with low/full speed dev, highspeed hub
370  * @ttport: device port on that tt hub
371  * @toggle: one bit for each endpoint, with ([0] = IN, [1] = OUT) endpoints
372  * @parent: our hub, unless we're the root
373  * @bus: bus we're part of
374  * @ep0: endpoint 0 data (default control pipe)
375  * @dev: generic device interface
376  * @descriptor: USB device descriptor
377  * @config: all of the device's configs
378  * @actconfig: the active configuration
379  * @ep_in: array of IN endpoints
380  * @ep_out: array of OUT endpoints
381  * @rawdescriptors: raw descriptors for each config
382  * @bus_mA: Current available from the bus
383  * @portnum: parent port number (origin 1)
384  * @level: number of USB hub ancestors
385  * @can_submit: URBs may be submitted
386  * @persist_enabled:  USB_PERSIST enabled for this device
387  * @have_langid: whether string_langid is valid
388  * @authorized: policy has said we can use it;
389  *	(user space) policy determines if we authorize this device to be
390  *	used or not. By default, wired USB devices are authorized.
391  *	WUSB devices are not, until we authorize them from user space.
392  *	FIXME -- complete doc
393  * @authenticated: Crypto authentication passed
394  * @wusb: device is Wireless USB
395  * @string_langid: language ID for strings
396  * @product: iProduct string, if present (static)
397  * @manufacturer: iManufacturer string, if present (static)
398  * @serial: iSerialNumber string, if present (static)
399  * @filelist: usbfs files that are open to this device
400  * @usb_classdev: USB class device that was created for usbfs device
401  *	access from userspace
402  * @usbfs_dentry: usbfs dentry entry for the device
403  * @maxchild: number of ports if hub
404  * @children: child devices - USB devices that are attached to this hub
405  * @quirks: quirks of the whole device
406  * @urbnum: number of URBs submitted for the whole device
407  * @active_duration: total time device is not suspended
408  * @last_busy: time of last use
409  * @autosuspend_delay: in jiffies
410  * @connect_time: time device was first connected
411  * @do_remote_wakeup:  remote wakeup should be enabled
412  * @reset_resume: needs reset instead of resume
413  * @wusb_dev: if this is a Wireless USB device, link to the WUSB
414  *	specific data for the device.
415  * @slot_id: Slot ID assigned by xHCI
416  *
417  * Notes:
418  * Usbcore drivers should not set usbdev->state directly.  Instead use
419  * usb_set_device_state().
420  */
421 struct usb_device {
422 	int		devnum;
423 	char		devpath[16];
424 	u32		route;
425 	enum usb_device_state	state;
426 	enum usb_device_speed	speed;
427 
428 	struct usb_tt	*tt;
429 	int		ttport;
430 
431 	unsigned int toggle[2];
432 
433 	struct usb_device *parent;
434 	struct usb_bus *bus;
435 	struct usb_host_endpoint ep0;
436 
437 	struct device dev;
438 
439 	struct usb_device_descriptor descriptor;
440 	struct usb_host_config *config;
441 
442 	struct usb_host_config *actconfig;
443 	struct usb_host_endpoint *ep_in[16];
444 	struct usb_host_endpoint *ep_out[16];
445 
446 	char **rawdescriptors;
447 
448 	unsigned short bus_mA;
449 	u8 portnum;
450 	u8 level;
451 
452 	unsigned can_submit:1;
453 	unsigned persist_enabled:1;
454 	unsigned have_langid:1;
455 	unsigned authorized:1;
456 	unsigned authenticated:1;
457 	unsigned wusb:1;
458 	int string_langid;
459 
460 	/* static strings from the device */
461 	char *product;
462 	char *manufacturer;
463 	char *serial;
464 
465 	struct list_head filelist;
466 #ifdef CONFIG_USB_DEVICE_CLASS
467 	struct device *usb_classdev;
468 #endif
469 #ifdef CONFIG_USB_DEVICEFS
470 	struct dentry *usbfs_dentry;
471 #endif
472 
473 	int maxchild;
474 	struct usb_device *children[USB_MAXCHILDREN];
475 
476 	u32 quirks;
477 	atomic_t urbnum;
478 
479 	unsigned long active_duration;
480 
481 #ifdef CONFIG_PM
482 	unsigned long last_busy;
483 	int autosuspend_delay;
484 	unsigned long connect_time;
485 
486 	unsigned do_remote_wakeup:1;
487 	unsigned reset_resume:1;
488 #endif
489 	struct wusb_dev *wusb_dev;
490 	int slot_id;
491 };
492 #define	to_usb_device(d) container_of(d, struct usb_device, dev)
493 
494 static inline struct usb_device *interface_to_usbdev(struct usb_interface *intf)
495 {
496 	return to_usb_device(intf->dev.parent);
497 }
498 
499 extern struct usb_device *usb_get_dev(struct usb_device *dev);
500 extern void usb_put_dev(struct usb_device *dev);
501 
502 /* USB device locking */
503 #define usb_lock_device(udev)		device_lock(&(udev)->dev)
504 #define usb_unlock_device(udev)		device_unlock(&(udev)->dev)
505 #define usb_trylock_device(udev)	device_trylock(&(udev)->dev)
506 extern int usb_lock_device_for_reset(struct usb_device *udev,
507 				     const struct usb_interface *iface);
508 
509 /* USB port reset for device reinitialization */
510 extern int usb_reset_device(struct usb_device *dev);
511 extern void usb_queue_reset_device(struct usb_interface *dev);
512 
513 
514 /* USB autosuspend and autoresume */
515 #ifdef CONFIG_USB_SUSPEND
516 extern void usb_enable_autosuspend(struct usb_device *udev);
517 extern void usb_disable_autosuspend(struct usb_device *udev);
518 
519 extern int usb_autopm_get_interface(struct usb_interface *intf);
520 extern void usb_autopm_put_interface(struct usb_interface *intf);
521 extern int usb_autopm_get_interface_async(struct usb_interface *intf);
522 extern void usb_autopm_put_interface_async(struct usb_interface *intf);
523 extern void usb_autopm_get_interface_no_resume(struct usb_interface *intf);
524 extern void usb_autopm_put_interface_no_suspend(struct usb_interface *intf);
525 
526 static inline void usb_mark_last_busy(struct usb_device *udev)
527 {
528 	udev->last_busy = jiffies;
529 }
530 
531 #else
532 
533 static inline int usb_enable_autosuspend(struct usb_device *udev)
534 { return 0; }
535 static inline int usb_disable_autosuspend(struct usb_device *udev)
536 { return 0; }
537 
538 static inline int usb_autopm_get_interface(struct usb_interface *intf)
539 { return 0; }
540 static inline int usb_autopm_get_interface_async(struct usb_interface *intf)
541 { return 0; }
542 
543 static inline void usb_autopm_put_interface(struct usb_interface *intf)
544 { }
545 static inline void usb_autopm_put_interface_async(struct usb_interface *intf)
546 { }
547 static inline void usb_autopm_get_interface_no_resume(
548 		struct usb_interface *intf)
549 { }
550 static inline void usb_autopm_put_interface_no_suspend(
551 		struct usb_interface *intf)
552 { }
553 static inline void usb_mark_last_busy(struct usb_device *udev)
554 { }
555 #endif
556 
557 /*-------------------------------------------------------------------------*/
558 
559 /* for drivers using iso endpoints */
560 extern int usb_get_current_frame_number(struct usb_device *usb_dev);
561 
562 /* Sets up a group of bulk endpoints to support multiple stream IDs. */
563 extern int usb_alloc_streams(struct usb_interface *interface,
564 		struct usb_host_endpoint **eps, unsigned int num_eps,
565 		unsigned int num_streams, gfp_t mem_flags);
566 
567 /* Reverts a group of bulk endpoints back to not using stream IDs. */
568 extern void usb_free_streams(struct usb_interface *interface,
569 		struct usb_host_endpoint **eps, unsigned int num_eps,
570 		gfp_t mem_flags);
571 
572 /* used these for multi-interface device registration */
573 extern int usb_driver_claim_interface(struct usb_driver *driver,
574 			struct usb_interface *iface, void *priv);
575 
576 /**
577  * usb_interface_claimed - returns true iff an interface is claimed
578  * @iface: the interface being checked
579  *
580  * Returns true (nonzero) iff the interface is claimed, else false (zero).
581  * Callers must own the driver model's usb bus readlock.  So driver
582  * probe() entries don't need extra locking, but other call contexts
583  * may need to explicitly claim that lock.
584  *
585  */
586 static inline int usb_interface_claimed(struct usb_interface *iface)
587 {
588 	return (iface->dev.driver != NULL);
589 }
590 
591 extern void usb_driver_release_interface(struct usb_driver *driver,
592 			struct usb_interface *iface);
593 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
594 					 const struct usb_device_id *id);
595 extern int usb_match_one_id(struct usb_interface *interface,
596 			    const struct usb_device_id *id);
597 
598 extern struct usb_interface *usb_find_interface(struct usb_driver *drv,
599 		int minor);
600 extern struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
601 		unsigned ifnum);
602 extern struct usb_host_interface *usb_altnum_to_altsetting(
603 		const struct usb_interface *intf, unsigned int altnum);
604 extern struct usb_host_interface *usb_find_alt_setting(
605 		struct usb_host_config *config,
606 		unsigned int iface_num,
607 		unsigned int alt_num);
608 
609 
610 /**
611  * usb_make_path - returns stable device path in the usb tree
612  * @dev: the device whose path is being constructed
613  * @buf: where to put the string
614  * @size: how big is "buf"?
615  *
616  * Returns length of the string (> 0) or negative if size was too small.
617  *
618  * This identifier is intended to be "stable", reflecting physical paths in
619  * hardware such as physical bus addresses for host controllers or ports on
620  * USB hubs.  That makes it stay the same until systems are physically
621  * reconfigured, by re-cabling a tree of USB devices or by moving USB host
622  * controllers.  Adding and removing devices, including virtual root hubs
623  * in host controller driver modules, does not change these path identifers;
624  * neither does rebooting or re-enumerating.  These are more useful identifiers
625  * than changeable ("unstable") ones like bus numbers or device addresses.
626  *
627  * With a partial exception for devices connected to USB 2.0 root hubs, these
628  * identifiers are also predictable.  So long as the device tree isn't changed,
629  * plugging any USB device into a given hub port always gives it the same path.
630  * Because of the use of "companion" controllers, devices connected to ports on
631  * USB 2.0 root hubs (EHCI host controllers) will get one path ID if they are
632  * high speed, and a different one if they are full or low speed.
633  */
634 static inline int usb_make_path(struct usb_device *dev, char *buf, size_t size)
635 {
636 	int actual;
637 	actual = snprintf(buf, size, "usb-%s-%s", dev->bus->bus_name,
638 			  dev->devpath);
639 	return (actual >= (int)size) ? -1 : actual;
640 }
641 
642 /*-------------------------------------------------------------------------*/
643 
644 #define USB_DEVICE_ID_MATCH_DEVICE \
645 		(USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT)
646 #define USB_DEVICE_ID_MATCH_DEV_RANGE \
647 		(USB_DEVICE_ID_MATCH_DEV_LO | USB_DEVICE_ID_MATCH_DEV_HI)
648 #define USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION \
649 		(USB_DEVICE_ID_MATCH_DEVICE | USB_DEVICE_ID_MATCH_DEV_RANGE)
650 #define USB_DEVICE_ID_MATCH_DEV_INFO \
651 		(USB_DEVICE_ID_MATCH_DEV_CLASS | \
652 		USB_DEVICE_ID_MATCH_DEV_SUBCLASS | \
653 		USB_DEVICE_ID_MATCH_DEV_PROTOCOL)
654 #define USB_DEVICE_ID_MATCH_INT_INFO \
655 		(USB_DEVICE_ID_MATCH_INT_CLASS | \
656 		USB_DEVICE_ID_MATCH_INT_SUBCLASS | \
657 		USB_DEVICE_ID_MATCH_INT_PROTOCOL)
658 
659 /**
660  * USB_DEVICE - macro used to describe a specific usb device
661  * @vend: the 16 bit USB Vendor ID
662  * @prod: the 16 bit USB Product ID
663  *
664  * This macro is used to create a struct usb_device_id that matches a
665  * specific device.
666  */
667 #define USB_DEVICE(vend, prod) \
668 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE, \
669 	.idVendor = (vend), \
670 	.idProduct = (prod)
671 /**
672  * USB_DEVICE_VER - describe a specific usb device with a version range
673  * @vend: the 16 bit USB Vendor ID
674  * @prod: the 16 bit USB Product ID
675  * @lo: the bcdDevice_lo value
676  * @hi: the bcdDevice_hi value
677  *
678  * This macro is used to create a struct usb_device_id that matches a
679  * specific device, with a version range.
680  */
681 #define USB_DEVICE_VER(vend, prod, lo, hi) \
682 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION, \
683 	.idVendor = (vend), \
684 	.idProduct = (prod), \
685 	.bcdDevice_lo = (lo), \
686 	.bcdDevice_hi = (hi)
687 
688 /**
689  * USB_DEVICE_INTERFACE_PROTOCOL - describe a usb device with a specific interface protocol
690  * @vend: the 16 bit USB Vendor ID
691  * @prod: the 16 bit USB Product ID
692  * @pr: bInterfaceProtocol value
693  *
694  * This macro is used to create a struct usb_device_id that matches a
695  * specific interface protocol of devices.
696  */
697 #define USB_DEVICE_INTERFACE_PROTOCOL(vend, prod, pr) \
698 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
699 		       USB_DEVICE_ID_MATCH_INT_PROTOCOL, \
700 	.idVendor = (vend), \
701 	.idProduct = (prod), \
702 	.bInterfaceProtocol = (pr)
703 
704 /**
705  * USB_DEVICE_INFO - macro used to describe a class of usb devices
706  * @cl: bDeviceClass value
707  * @sc: bDeviceSubClass value
708  * @pr: bDeviceProtocol value
709  *
710  * This macro is used to create a struct usb_device_id that matches a
711  * specific class of devices.
712  */
713 #define USB_DEVICE_INFO(cl, sc, pr) \
714 	.match_flags = USB_DEVICE_ID_MATCH_DEV_INFO, \
715 	.bDeviceClass = (cl), \
716 	.bDeviceSubClass = (sc), \
717 	.bDeviceProtocol = (pr)
718 
719 /**
720  * USB_INTERFACE_INFO - macro used to describe a class of usb interfaces
721  * @cl: bInterfaceClass value
722  * @sc: bInterfaceSubClass value
723  * @pr: bInterfaceProtocol value
724  *
725  * This macro is used to create a struct usb_device_id that matches a
726  * specific class of interfaces.
727  */
728 #define USB_INTERFACE_INFO(cl, sc, pr) \
729 	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO, \
730 	.bInterfaceClass = (cl), \
731 	.bInterfaceSubClass = (sc), \
732 	.bInterfaceProtocol = (pr)
733 
734 /**
735  * USB_DEVICE_AND_INTERFACE_INFO - describe a specific usb device with a class of usb interfaces
736  * @vend: the 16 bit USB Vendor ID
737  * @prod: the 16 bit USB Product ID
738  * @cl: bInterfaceClass value
739  * @sc: bInterfaceSubClass value
740  * @pr: bInterfaceProtocol value
741  *
742  * This macro is used to create a struct usb_device_id that matches a
743  * specific device with a specific class of interfaces.
744  *
745  * This is especially useful when explicitly matching devices that have
746  * vendor specific bDeviceClass values, but standards-compliant interfaces.
747  */
748 #define USB_DEVICE_AND_INTERFACE_INFO(vend, prod, cl, sc, pr) \
749 	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO \
750 		| USB_DEVICE_ID_MATCH_DEVICE, \
751 	.idVendor = (vend), \
752 	.idProduct = (prod), \
753 	.bInterfaceClass = (cl), \
754 	.bInterfaceSubClass = (sc), \
755 	.bInterfaceProtocol = (pr)
756 
757 /* ----------------------------------------------------------------------- */
758 
759 /* Stuff for dynamic usb ids */
760 struct usb_dynids {
761 	spinlock_t lock;
762 	struct list_head list;
763 };
764 
765 struct usb_dynid {
766 	struct list_head node;
767 	struct usb_device_id id;
768 };
769 
770 extern ssize_t usb_store_new_id(struct usb_dynids *dynids,
771 				struct device_driver *driver,
772 				const char *buf, size_t count);
773 
774 /**
775  * struct usbdrv_wrap - wrapper for driver-model structure
776  * @driver: The driver-model core driver structure.
777  * @for_devices: Non-zero for device drivers, 0 for interface drivers.
778  */
779 struct usbdrv_wrap {
780 	struct device_driver driver;
781 	int for_devices;
782 };
783 
784 /**
785  * struct usb_driver - identifies USB interface driver to usbcore
786  * @name: The driver name should be unique among USB drivers,
787  *	and should normally be the same as the module name.
788  * @probe: Called to see if the driver is willing to manage a particular
789  *	interface on a device.  If it is, probe returns zero and uses
790  *	usb_set_intfdata() to associate driver-specific data with the
791  *	interface.  It may also use usb_set_interface() to specify the
792  *	appropriate altsetting.  If unwilling to manage the interface,
793  *	return -ENODEV, if genuine IO errors occured, an appropriate
794  *	negative errno value.
795  * @disconnect: Called when the interface is no longer accessible, usually
796  *	because its device has been (or is being) disconnected or the
797  *	driver module is being unloaded.
798  * @ioctl: Used for drivers that want to talk to userspace through
799  *	the "usbfs" filesystem.  This lets devices provide ways to
800  *	expose information to user space regardless of where they
801  *	do (or don't) show up otherwise in the filesystem.
802  * @suspend: Called when the device is going to be suspended by the system.
803  * @resume: Called when the device is being resumed by the system.
804  * @reset_resume: Called when the suspended device has been reset instead
805  *	of being resumed.
806  * @pre_reset: Called by usb_reset_device() when the device
807  *	is about to be reset.
808  * @post_reset: Called by usb_reset_device() after the device
809  *	has been reset
810  * @id_table: USB drivers use ID table to support hotplugging.
811  *	Export this with MODULE_DEVICE_TABLE(usb,...).  This must be set
812  *	or your driver's probe function will never get called.
813  * @dynids: used internally to hold the list of dynamically added device
814  *	ids for this driver.
815  * @drvwrap: Driver-model core structure wrapper.
816  * @no_dynamic_id: if set to 1, the USB core will not allow dynamic ids to be
817  *	added to this driver by preventing the sysfs file from being created.
818  * @supports_autosuspend: if set to 0, the USB core will not allow autosuspend
819  *	for interfaces bound to this driver.
820  * @soft_unbind: if set to 1, the USB core will not kill URBs and disable
821  *	endpoints before calling the driver's disconnect method.
822  *
823  * USB interface drivers must provide a name, probe() and disconnect()
824  * methods, and an id_table.  Other driver fields are optional.
825  *
826  * The id_table is used in hotplugging.  It holds a set of descriptors,
827  * and specialized data may be associated with each entry.  That table
828  * is used by both user and kernel mode hotplugging support.
829  *
830  * The probe() and disconnect() methods are called in a context where
831  * they can sleep, but they should avoid abusing the privilege.  Most
832  * work to connect to a device should be done when the device is opened,
833  * and undone at the last close.  The disconnect code needs to address
834  * concurrency issues with respect to open() and close() methods, as
835  * well as forcing all pending I/O requests to complete (by unlinking
836  * them as necessary, and blocking until the unlinks complete).
837  */
838 struct usb_driver {
839 	const char *name;
840 
841 	int (*probe) (struct usb_interface *intf,
842 		      const struct usb_device_id *id);
843 
844 	void (*disconnect) (struct usb_interface *intf);
845 
846 	int (*ioctl) (struct usb_interface *intf, unsigned int code,
847 			void *buf);
848 
849 	int (*suspend) (struct usb_interface *intf, pm_message_t message);
850 	int (*resume) (struct usb_interface *intf);
851 	int (*reset_resume)(struct usb_interface *intf);
852 
853 	int (*pre_reset)(struct usb_interface *intf);
854 	int (*post_reset)(struct usb_interface *intf);
855 
856 	const struct usb_device_id *id_table;
857 
858 	struct usb_dynids dynids;
859 	struct usbdrv_wrap drvwrap;
860 	unsigned int no_dynamic_id:1;
861 	unsigned int supports_autosuspend:1;
862 	unsigned int soft_unbind:1;
863 };
864 #define	to_usb_driver(d) container_of(d, struct usb_driver, drvwrap.driver)
865 
866 /**
867  * struct usb_device_driver - identifies USB device driver to usbcore
868  * @name: The driver name should be unique among USB drivers,
869  *	and should normally be the same as the module name.
870  * @probe: Called to see if the driver is willing to manage a particular
871  *	device.  If it is, probe returns zero and uses dev_set_drvdata()
872  *	to associate driver-specific data with the device.  If unwilling
873  *	to manage the device, return a negative errno value.
874  * @disconnect: Called when the device is no longer accessible, usually
875  *	because it has been (or is being) disconnected or the driver's
876  *	module is being unloaded.
877  * @suspend: Called when the device is going to be suspended by the system.
878  * @resume: Called when the device is being resumed by the system.
879  * @drvwrap: Driver-model core structure wrapper.
880  * @supports_autosuspend: if set to 0, the USB core will not allow autosuspend
881  *	for devices bound to this driver.
882  *
883  * USB drivers must provide all the fields listed above except drvwrap.
884  */
885 struct usb_device_driver {
886 	const char *name;
887 
888 	int (*probe) (struct usb_device *udev);
889 	void (*disconnect) (struct usb_device *udev);
890 
891 	int (*suspend) (struct usb_device *udev, pm_message_t message);
892 	int (*resume) (struct usb_device *udev, pm_message_t message);
893 	struct usbdrv_wrap drvwrap;
894 	unsigned int supports_autosuspend:1;
895 };
896 #define	to_usb_device_driver(d) container_of(d, struct usb_device_driver, \
897 		drvwrap.driver)
898 
899 extern struct bus_type usb_bus_type;
900 
901 /**
902  * struct usb_class_driver - identifies a USB driver that wants to use the USB major number
903  * @name: the usb class device name for this driver.  Will show up in sysfs.
904  * @devnode: Callback to provide a naming hint for a possible
905  *	device node to create.
906  * @fops: pointer to the struct file_operations of this driver.
907  * @minor_base: the start of the minor range for this driver.
908  *
909  * This structure is used for the usb_register_dev() and
910  * usb_unregister_dev() functions, to consolidate a number of the
911  * parameters used for them.
912  */
913 struct usb_class_driver {
914 	char *name;
915 	char *(*devnode)(struct device *dev, mode_t *mode);
916 	const struct file_operations *fops;
917 	int minor_base;
918 };
919 
920 /*
921  * use these in module_init()/module_exit()
922  * and don't forget MODULE_DEVICE_TABLE(usb, ...)
923  */
924 extern int usb_register_driver(struct usb_driver *, struct module *,
925 			       const char *);
926 static inline int usb_register(struct usb_driver *driver)
927 {
928 	return usb_register_driver(driver, THIS_MODULE, KBUILD_MODNAME);
929 }
930 extern void usb_deregister(struct usb_driver *);
931 
932 extern int usb_register_device_driver(struct usb_device_driver *,
933 			struct module *);
934 extern void usb_deregister_device_driver(struct usb_device_driver *);
935 
936 extern int usb_register_dev(struct usb_interface *intf,
937 			    struct usb_class_driver *class_driver);
938 extern void usb_deregister_dev(struct usb_interface *intf,
939 			       struct usb_class_driver *class_driver);
940 
941 extern int usb_disabled(void);
942 
943 /* ----------------------------------------------------------------------- */
944 
945 /*
946  * URB support, for asynchronous request completions
947  */
948 
949 /*
950  * urb->transfer_flags:
951  *
952  * Note: URB_DIR_IN/OUT is automatically set in usb_submit_urb().
953  */
954 #define URB_SHORT_NOT_OK	0x0001	/* report short reads as errors */
955 #define URB_ISO_ASAP		0x0002	/* iso-only, urb->start_frame
956 					 * ignored */
957 #define URB_NO_TRANSFER_DMA_MAP	0x0004	/* urb->transfer_dma valid on submit */
958 #define URB_NO_FSBR		0x0020	/* UHCI-specific */
959 #define URB_ZERO_PACKET		0x0040	/* Finish bulk OUT with short packet */
960 #define URB_NO_INTERRUPT	0x0080	/* HINT: no non-error interrupt
961 					 * needed */
962 #define URB_FREE_BUFFER		0x0100	/* Free transfer buffer with the URB */
963 
964 /* The following flags are used internally by usbcore and HCDs */
965 #define URB_DIR_IN		0x0200	/* Transfer from device to host */
966 #define URB_DIR_OUT		0
967 #define URB_DIR_MASK		URB_DIR_IN
968 
969 #define URB_DMA_MAP_SINGLE	0x00010000	/* Non-scatter-gather mapping */
970 #define URB_DMA_MAP_PAGE	0x00020000	/* HCD-unsupported S-G */
971 #define URB_DMA_MAP_SG		0x00040000	/* HCD-supported S-G */
972 #define URB_MAP_LOCAL		0x00080000	/* HCD-local-memory mapping */
973 #define URB_SETUP_MAP_SINGLE	0x00100000	/* Setup packet DMA mapped */
974 #define URB_SETUP_MAP_LOCAL	0x00200000	/* HCD-local setup packet */
975 #define URB_DMA_SG_COMBINED	0x00400000	/* S-G entries were combined */
976 
977 struct usb_iso_packet_descriptor {
978 	unsigned int offset;
979 	unsigned int length;		/* expected length */
980 	unsigned int actual_length;
981 	int status;
982 };
983 
984 struct urb;
985 
986 struct usb_anchor {
987 	struct list_head urb_list;
988 	wait_queue_head_t wait;
989 	spinlock_t lock;
990 	unsigned int poisoned:1;
991 };
992 
993 static inline void init_usb_anchor(struct usb_anchor *anchor)
994 {
995 	INIT_LIST_HEAD(&anchor->urb_list);
996 	init_waitqueue_head(&anchor->wait);
997 	spin_lock_init(&anchor->lock);
998 }
999 
1000 typedef void (*usb_complete_t)(struct urb *);
1001 
1002 /**
1003  * struct urb - USB Request Block
1004  * @urb_list: For use by current owner of the URB.
1005  * @anchor_list: membership in the list of an anchor
1006  * @anchor: to anchor URBs to a common mooring
1007  * @ep: Points to the endpoint's data structure.  Will eventually
1008  *	replace @pipe.
1009  * @pipe: Holds endpoint number, direction, type, and more.
1010  *	Create these values with the eight macros available;
1011  *	usb_{snd,rcv}TYPEpipe(dev,endpoint), where the TYPE is "ctrl"
1012  *	(control), "bulk", "int" (interrupt), or "iso" (isochronous).
1013  *	For example usb_sndbulkpipe() or usb_rcvintpipe().  Endpoint
1014  *	numbers range from zero to fifteen.  Note that "in" endpoint two
1015  *	is a different endpoint (and pipe) from "out" endpoint two.
1016  *	The current configuration controls the existence, type, and
1017  *	maximum packet size of any given endpoint.
1018  * @dev: Identifies the USB device to perform the request.
1019  * @status: This is read in non-iso completion functions to get the
1020  *	status of the particular request.  ISO requests only use it
1021  *	to tell whether the URB was unlinked; detailed status for
1022  *	each frame is in the fields of the iso_frame-desc.
1023  * @transfer_flags: A variety of flags may be used to affect how URB
1024  *	submission, unlinking, or operation are handled.  Different
1025  *	kinds of URB can use different flags.
1026  * @transfer_buffer:  This identifies the buffer to (or from) which the I/O
1027  *	request will be performed unless URB_NO_TRANSFER_DMA_MAP is set
1028  *	(however, do not leave garbage in transfer_buffer even then).
1029  *	This buffer must be suitable for DMA; allocate it with
1030  *	kmalloc() or equivalent.  For transfers to "in" endpoints, contents
1031  *	of this buffer will be modified.  This buffer is used for the data
1032  *	stage of control transfers.
1033  * @transfer_dma: When transfer_flags includes URB_NO_TRANSFER_DMA_MAP,
1034  *	the device driver is saying that it provided this DMA address,
1035  *	which the host controller driver should use in preference to the
1036  *	transfer_buffer.
1037  * @sg: scatter gather buffer list
1038  * @num_sgs: number of entries in the sg list
1039  * @transfer_buffer_length: How big is transfer_buffer.  The transfer may
1040  *	be broken up into chunks according to the current maximum packet
1041  *	size for the endpoint, which is a function of the configuration
1042  *	and is encoded in the pipe.  When the length is zero, neither
1043  *	transfer_buffer nor transfer_dma is used.
1044  * @actual_length: This is read in non-iso completion functions, and
1045  *	it tells how many bytes (out of transfer_buffer_length) were
1046  *	transferred.  It will normally be the same as requested, unless
1047  *	either an error was reported or a short read was performed.
1048  *	The URB_SHORT_NOT_OK transfer flag may be used to make such
1049  *	short reads be reported as errors.
1050  * @setup_packet: Only used for control transfers, this points to eight bytes
1051  *	of setup data.  Control transfers always start by sending this data
1052  *	to the device.  Then transfer_buffer is read or written, if needed.
1053  * @setup_dma: DMA pointer for the setup packet.  The caller must not use
1054  *	this field; setup_packet must point to a valid buffer.
1055  * @start_frame: Returns the initial frame for isochronous transfers.
1056  * @number_of_packets: Lists the number of ISO transfer buffers.
1057  * @interval: Specifies the polling interval for interrupt or isochronous
1058  *	transfers.  The units are frames (milliseconds) for full and low
1059  *	speed devices, and microframes (1/8 millisecond) for highspeed
1060  *	and SuperSpeed devices.
1061  * @error_count: Returns the number of ISO transfers that reported errors.
1062  * @context: For use in completion functions.  This normally points to
1063  *	request-specific driver context.
1064  * @complete: Completion handler. This URB is passed as the parameter to the
1065  *	completion function.  The completion function may then do what
1066  *	it likes with the URB, including resubmitting or freeing it.
1067  * @iso_frame_desc: Used to provide arrays of ISO transfer buffers and to
1068  *	collect the transfer status for each buffer.
1069  *
1070  * This structure identifies USB transfer requests.  URBs must be allocated by
1071  * calling usb_alloc_urb() and freed with a call to usb_free_urb().
1072  * Initialization may be done using various usb_fill_*_urb() functions.  URBs
1073  * are submitted using usb_submit_urb(), and pending requests may be canceled
1074  * using usb_unlink_urb() or usb_kill_urb().
1075  *
1076  * Data Transfer Buffers:
1077  *
1078  * Normally drivers provide I/O buffers allocated with kmalloc() or otherwise
1079  * taken from the general page pool.  That is provided by transfer_buffer
1080  * (control requests also use setup_packet), and host controller drivers
1081  * perform a dma mapping (and unmapping) for each buffer transferred.  Those
1082  * mapping operations can be expensive on some platforms (perhaps using a dma
1083  * bounce buffer or talking to an IOMMU),
1084  * although they're cheap on commodity x86 and ppc hardware.
1085  *
1086  * Alternatively, drivers may pass the URB_NO_TRANSFER_DMA_MAP transfer flag,
1087  * which tells the host controller driver that no such mapping is needed for
1088  * the transfer_buffer since
1089  * the device driver is DMA-aware.  For example, a device driver might
1090  * allocate a DMA buffer with usb_alloc_coherent() or call usb_buffer_map().
1091  * When this transfer flag is provided, host controller drivers will
1092  * attempt to use the dma address found in the transfer_dma
1093  * field rather than determining a dma address themselves.
1094  *
1095  * Note that transfer_buffer must still be set if the controller
1096  * does not support DMA (as indicated by bus.uses_dma) and when talking
1097  * to root hub. If you have to trasfer between highmem zone and the device
1098  * on such controller, create a bounce buffer or bail out with an error.
1099  * If transfer_buffer cannot be set (is in highmem) and the controller is DMA
1100  * capable, assign NULL to it, so that usbmon knows not to use the value.
1101  * The setup_packet must always be set, so it cannot be located in highmem.
1102  *
1103  * Initialization:
1104  *
1105  * All URBs submitted must initialize the dev, pipe, transfer_flags (may be
1106  * zero), and complete fields.  All URBs must also initialize
1107  * transfer_buffer and transfer_buffer_length.  They may provide the
1108  * URB_SHORT_NOT_OK transfer flag, indicating that short reads are
1109  * to be treated as errors; that flag is invalid for write requests.
1110  *
1111  * Bulk URBs may
1112  * use the URB_ZERO_PACKET transfer flag, indicating that bulk OUT transfers
1113  * should always terminate with a short packet, even if it means adding an
1114  * extra zero length packet.
1115  *
1116  * Control URBs must provide a valid pointer in the setup_packet field.
1117  * Unlike the transfer_buffer, the setup_packet may not be mapped for DMA
1118  * beforehand.
1119  *
1120  * Interrupt URBs must provide an interval, saying how often (in milliseconds
1121  * or, for highspeed devices, 125 microsecond units)
1122  * to poll for transfers.  After the URB has been submitted, the interval
1123  * field reflects how the transfer was actually scheduled.
1124  * The polling interval may be more frequent than requested.
1125  * For example, some controllers have a maximum interval of 32 milliseconds,
1126  * while others support intervals of up to 1024 milliseconds.
1127  * Isochronous URBs also have transfer intervals.  (Note that for isochronous
1128  * endpoints, as well as high speed interrupt endpoints, the encoding of
1129  * the transfer interval in the endpoint descriptor is logarithmic.
1130  * Device drivers must convert that value to linear units themselves.)
1131  *
1132  * Isochronous URBs normally use the URB_ISO_ASAP transfer flag, telling
1133  * the host controller to schedule the transfer as soon as bandwidth
1134  * utilization allows, and then set start_frame to reflect the actual frame
1135  * selected during submission.  Otherwise drivers must specify the start_frame
1136  * and handle the case where the transfer can't begin then.  However, drivers
1137  * won't know how bandwidth is currently allocated, and while they can
1138  * find the current frame using usb_get_current_frame_number () they can't
1139  * know the range for that frame number.  (Ranges for frame counter values
1140  * are HC-specific, and can go from 256 to 65536 frames from "now".)
1141  *
1142  * Isochronous URBs have a different data transfer model, in part because
1143  * the quality of service is only "best effort".  Callers provide specially
1144  * allocated URBs, with number_of_packets worth of iso_frame_desc structures
1145  * at the end.  Each such packet is an individual ISO transfer.  Isochronous
1146  * URBs are normally queued, submitted by drivers to arrange that
1147  * transfers are at least double buffered, and then explicitly resubmitted
1148  * in completion handlers, so
1149  * that data (such as audio or video) streams at as constant a rate as the
1150  * host controller scheduler can support.
1151  *
1152  * Completion Callbacks:
1153  *
1154  * The completion callback is made in_interrupt(), and one of the first
1155  * things that a completion handler should do is check the status field.
1156  * The status field is provided for all URBs.  It is used to report
1157  * unlinked URBs, and status for all non-ISO transfers.  It should not
1158  * be examined before the URB is returned to the completion handler.
1159  *
1160  * The context field is normally used to link URBs back to the relevant
1161  * driver or request state.
1162  *
1163  * When the completion callback is invoked for non-isochronous URBs, the
1164  * actual_length field tells how many bytes were transferred.  This field
1165  * is updated even when the URB terminated with an error or was unlinked.
1166  *
1167  * ISO transfer status is reported in the status and actual_length fields
1168  * of the iso_frame_desc array, and the number of errors is reported in
1169  * error_count.  Completion callbacks for ISO transfers will normally
1170  * (re)submit URBs to ensure a constant transfer rate.
1171  *
1172  * Note that even fields marked "public" should not be touched by the driver
1173  * when the urb is owned by the hcd, that is, since the call to
1174  * usb_submit_urb() till the entry into the completion routine.
1175  */
1176 struct urb {
1177 	/* private: usb core and host controller only fields in the urb */
1178 	struct kref kref;		/* reference count of the URB */
1179 	void *hcpriv;			/* private data for host controller */
1180 	atomic_t use_count;		/* concurrent submissions counter */
1181 	atomic_t reject;		/* submissions will fail */
1182 	int unlinked;			/* unlink error code */
1183 
1184 	/* public: documented fields in the urb that can be used by drivers */
1185 	struct list_head urb_list;	/* list head for use by the urb's
1186 					 * current owner */
1187 	struct list_head anchor_list;	/* the URB may be anchored */
1188 	struct usb_anchor *anchor;
1189 	struct usb_device *dev;		/* (in) pointer to associated device */
1190 	struct usb_host_endpoint *ep;	/* (internal) pointer to endpoint */
1191 	unsigned int pipe;		/* (in) pipe information */
1192 	unsigned int stream_id;		/* (in) stream ID */
1193 	int status;			/* (return) non-ISO status */
1194 	unsigned int transfer_flags;	/* (in) URB_SHORT_NOT_OK | ...*/
1195 	void *transfer_buffer;		/* (in) associated data buffer */
1196 	dma_addr_t transfer_dma;	/* (in) dma addr for transfer_buffer */
1197 	struct scatterlist *sg;		/* (in) scatter gather buffer list */
1198 	int num_sgs;			/* (in) number of entries in the sg list */
1199 	u32 transfer_buffer_length;	/* (in) data buffer length */
1200 	u32 actual_length;		/* (return) actual transfer length */
1201 	unsigned char *setup_packet;	/* (in) setup packet (control only) */
1202 	dma_addr_t setup_dma;		/* (in) dma addr for setup_packet */
1203 	int start_frame;		/* (modify) start frame (ISO) */
1204 	int number_of_packets;		/* (in) number of ISO packets */
1205 	int interval;			/* (modify) transfer interval
1206 					 * (INT/ISO) */
1207 	int error_count;		/* (return) number of ISO errors */
1208 	void *context;			/* (in) context for completion */
1209 	usb_complete_t complete;	/* (in) completion routine */
1210 	struct usb_iso_packet_descriptor iso_frame_desc[0];
1211 					/* (in) ISO ONLY */
1212 };
1213 
1214 /* ----------------------------------------------------------------------- */
1215 
1216 /**
1217  * usb_fill_control_urb - initializes a control urb
1218  * @urb: pointer to the urb to initialize.
1219  * @dev: pointer to the struct usb_device for this urb.
1220  * @pipe: the endpoint pipe
1221  * @setup_packet: pointer to the setup_packet buffer
1222  * @transfer_buffer: pointer to the transfer buffer
1223  * @buffer_length: length of the transfer buffer
1224  * @complete_fn: pointer to the usb_complete_t function
1225  * @context: what to set the urb context to.
1226  *
1227  * Initializes a control urb with the proper information needed to submit
1228  * it to a device.
1229  */
1230 static inline void usb_fill_control_urb(struct urb *urb,
1231 					struct usb_device *dev,
1232 					unsigned int pipe,
1233 					unsigned char *setup_packet,
1234 					void *transfer_buffer,
1235 					int buffer_length,
1236 					usb_complete_t complete_fn,
1237 					void *context)
1238 {
1239 	urb->dev = dev;
1240 	urb->pipe = pipe;
1241 	urb->setup_packet = setup_packet;
1242 	urb->transfer_buffer = transfer_buffer;
1243 	urb->transfer_buffer_length = buffer_length;
1244 	urb->complete = complete_fn;
1245 	urb->context = context;
1246 }
1247 
1248 /**
1249  * usb_fill_bulk_urb - macro to help initialize a bulk urb
1250  * @urb: pointer to the urb to initialize.
1251  * @dev: pointer to the struct usb_device for this urb.
1252  * @pipe: the endpoint pipe
1253  * @transfer_buffer: pointer to the transfer buffer
1254  * @buffer_length: length of the transfer buffer
1255  * @complete_fn: pointer to the usb_complete_t function
1256  * @context: what to set the urb context to.
1257  *
1258  * Initializes a bulk urb with the proper information needed to submit it
1259  * to a device.
1260  */
1261 static inline void usb_fill_bulk_urb(struct urb *urb,
1262 				     struct usb_device *dev,
1263 				     unsigned int pipe,
1264 				     void *transfer_buffer,
1265 				     int buffer_length,
1266 				     usb_complete_t complete_fn,
1267 				     void *context)
1268 {
1269 	urb->dev = dev;
1270 	urb->pipe = pipe;
1271 	urb->transfer_buffer = transfer_buffer;
1272 	urb->transfer_buffer_length = buffer_length;
1273 	urb->complete = complete_fn;
1274 	urb->context = context;
1275 }
1276 
1277 /**
1278  * usb_fill_int_urb - macro to help initialize a interrupt urb
1279  * @urb: pointer to the urb to initialize.
1280  * @dev: pointer to the struct usb_device for this urb.
1281  * @pipe: the endpoint pipe
1282  * @transfer_buffer: pointer to the transfer buffer
1283  * @buffer_length: length of the transfer buffer
1284  * @complete_fn: pointer to the usb_complete_t function
1285  * @context: what to set the urb context to.
1286  * @interval: what to set the urb interval to, encoded like
1287  *	the endpoint descriptor's bInterval value.
1288  *
1289  * Initializes a interrupt urb with the proper information needed to submit
1290  * it to a device.
1291  *
1292  * Note that High Speed and SuperSpeed interrupt endpoints use a logarithmic
1293  * encoding of the endpoint interval, and express polling intervals in
1294  * microframes (eight per millisecond) rather than in frames (one per
1295  * millisecond).
1296  *
1297  * Wireless USB also uses the logarithmic encoding, but specifies it in units of
1298  * 128us instead of 125us.  For Wireless USB devices, the interval is passed
1299  * through to the host controller, rather than being translated into microframe
1300  * units.
1301  */
1302 static inline void usb_fill_int_urb(struct urb *urb,
1303 				    struct usb_device *dev,
1304 				    unsigned int pipe,
1305 				    void *transfer_buffer,
1306 				    int buffer_length,
1307 				    usb_complete_t complete_fn,
1308 				    void *context,
1309 				    int interval)
1310 {
1311 	urb->dev = dev;
1312 	urb->pipe = pipe;
1313 	urb->transfer_buffer = transfer_buffer;
1314 	urb->transfer_buffer_length = buffer_length;
1315 	urb->complete = complete_fn;
1316 	urb->context = context;
1317 	if (dev->speed == USB_SPEED_HIGH || dev->speed == USB_SPEED_SUPER)
1318 		urb->interval = 1 << (interval - 1);
1319 	else
1320 		urb->interval = interval;
1321 	urb->start_frame = -1;
1322 }
1323 
1324 extern void usb_init_urb(struct urb *urb);
1325 extern struct urb *usb_alloc_urb(int iso_packets, gfp_t mem_flags);
1326 extern void usb_free_urb(struct urb *urb);
1327 #define usb_put_urb usb_free_urb
1328 extern struct urb *usb_get_urb(struct urb *urb);
1329 extern int usb_submit_urb(struct urb *urb, gfp_t mem_flags);
1330 extern int usb_unlink_urb(struct urb *urb);
1331 extern void usb_kill_urb(struct urb *urb);
1332 extern void usb_poison_urb(struct urb *urb);
1333 extern void usb_unpoison_urb(struct urb *urb);
1334 extern void usb_kill_anchored_urbs(struct usb_anchor *anchor);
1335 extern void usb_poison_anchored_urbs(struct usb_anchor *anchor);
1336 extern void usb_unpoison_anchored_urbs(struct usb_anchor *anchor);
1337 extern void usb_unlink_anchored_urbs(struct usb_anchor *anchor);
1338 extern void usb_anchor_urb(struct urb *urb, struct usb_anchor *anchor);
1339 extern void usb_unanchor_urb(struct urb *urb);
1340 extern int usb_wait_anchor_empty_timeout(struct usb_anchor *anchor,
1341 					 unsigned int timeout);
1342 extern struct urb *usb_get_from_anchor(struct usb_anchor *anchor);
1343 extern void usb_scuttle_anchored_urbs(struct usb_anchor *anchor);
1344 extern int usb_anchor_empty(struct usb_anchor *anchor);
1345 
1346 /**
1347  * usb_urb_dir_in - check if an URB describes an IN transfer
1348  * @urb: URB to be checked
1349  *
1350  * Returns 1 if @urb describes an IN transfer (device-to-host),
1351  * otherwise 0.
1352  */
1353 static inline int usb_urb_dir_in(struct urb *urb)
1354 {
1355 	return (urb->transfer_flags & URB_DIR_MASK) == URB_DIR_IN;
1356 }
1357 
1358 /**
1359  * usb_urb_dir_out - check if an URB describes an OUT transfer
1360  * @urb: URB to be checked
1361  *
1362  * Returns 1 if @urb describes an OUT transfer (host-to-device),
1363  * otherwise 0.
1364  */
1365 static inline int usb_urb_dir_out(struct urb *urb)
1366 {
1367 	return (urb->transfer_flags & URB_DIR_MASK) == URB_DIR_OUT;
1368 }
1369 
1370 void *usb_alloc_coherent(struct usb_device *dev, size_t size,
1371 	gfp_t mem_flags, dma_addr_t *dma);
1372 void usb_free_coherent(struct usb_device *dev, size_t size,
1373 	void *addr, dma_addr_t dma);
1374 
1375 #if 0
1376 struct urb *usb_buffer_map(struct urb *urb);
1377 void usb_buffer_dmasync(struct urb *urb);
1378 void usb_buffer_unmap(struct urb *urb);
1379 #endif
1380 
1381 struct scatterlist;
1382 int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
1383 		      struct scatterlist *sg, int nents);
1384 #if 0
1385 void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
1386 			   struct scatterlist *sg, int n_hw_ents);
1387 #endif
1388 void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
1389 			 struct scatterlist *sg, int n_hw_ents);
1390 
1391 /*-------------------------------------------------------------------*
1392  *                         SYNCHRONOUS CALL SUPPORT                  *
1393  *-------------------------------------------------------------------*/
1394 
1395 extern int usb_control_msg(struct usb_device *dev, unsigned int pipe,
1396 	__u8 request, __u8 requesttype, __u16 value, __u16 index,
1397 	void *data, __u16 size, int timeout);
1398 extern int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,
1399 	void *data, int len, int *actual_length, int timeout);
1400 extern int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,
1401 	void *data, int len, int *actual_length,
1402 	int timeout);
1403 
1404 /* wrappers around usb_control_msg() for the most common standard requests */
1405 extern int usb_get_descriptor(struct usb_device *dev, unsigned char desctype,
1406 	unsigned char descindex, void *buf, int size);
1407 extern int usb_get_status(struct usb_device *dev,
1408 	int type, int target, void *data);
1409 extern int usb_string(struct usb_device *dev, int index,
1410 	char *buf, size_t size);
1411 
1412 /* wrappers that also update important state inside usbcore */
1413 extern int usb_clear_halt(struct usb_device *dev, int pipe);
1414 extern int usb_reset_configuration(struct usb_device *dev);
1415 extern int usb_set_interface(struct usb_device *dev, int ifnum, int alternate);
1416 extern void usb_reset_endpoint(struct usb_device *dev, unsigned int epaddr);
1417 
1418 /* this request isn't really synchronous, but it belongs with the others */
1419 extern int usb_driver_set_configuration(struct usb_device *udev, int config);
1420 
1421 /*
1422  * timeouts, in milliseconds, used for sending/receiving control messages
1423  * they typically complete within a few frames (msec) after they're issued
1424  * USB identifies 5 second timeouts, maybe more in a few cases, and a few
1425  * slow devices (like some MGE Ellipse UPSes) actually push that limit.
1426  */
1427 #define USB_CTRL_GET_TIMEOUT	5000
1428 #define USB_CTRL_SET_TIMEOUT	5000
1429 
1430 
1431 /**
1432  * struct usb_sg_request - support for scatter/gather I/O
1433  * @status: zero indicates success, else negative errno
1434  * @bytes: counts bytes transferred.
1435  *
1436  * These requests are initialized using usb_sg_init(), and then are used
1437  * as request handles passed to usb_sg_wait() or usb_sg_cancel().  Most
1438  * members of the request object aren't for driver access.
1439  *
1440  * The status and bytecount values are valid only after usb_sg_wait()
1441  * returns.  If the status is zero, then the bytecount matches the total
1442  * from the request.
1443  *
1444  * After an error completion, drivers may need to clear a halt condition
1445  * on the endpoint.
1446  */
1447 struct usb_sg_request {
1448 	int			status;
1449 	size_t			bytes;
1450 
1451 	/* private:
1452 	 * members below are private to usbcore,
1453 	 * and are not provided for driver access!
1454 	 */
1455 	spinlock_t		lock;
1456 
1457 	struct usb_device	*dev;
1458 	int			pipe;
1459 
1460 	int			entries;
1461 	struct urb		**urbs;
1462 
1463 	int			count;
1464 	struct completion	complete;
1465 };
1466 
1467 int usb_sg_init(
1468 	struct usb_sg_request	*io,
1469 	struct usb_device	*dev,
1470 	unsigned		pipe,
1471 	unsigned		period,
1472 	struct scatterlist	*sg,
1473 	int			nents,
1474 	size_t			length,
1475 	gfp_t			mem_flags
1476 );
1477 void usb_sg_cancel(struct usb_sg_request *io);
1478 void usb_sg_wait(struct usb_sg_request *io);
1479 
1480 
1481 /* ----------------------------------------------------------------------- */
1482 
1483 /*
1484  * For various legacy reasons, Linux has a small cookie that's paired with
1485  * a struct usb_device to identify an endpoint queue.  Queue characteristics
1486  * are defined by the endpoint's descriptor.  This cookie is called a "pipe",
1487  * an unsigned int encoded as:
1488  *
1489  *  - direction:	bit 7		(0 = Host-to-Device [Out],
1490  *					 1 = Device-to-Host [In] ...
1491  *					like endpoint bEndpointAddress)
1492  *  - device address:	bits 8-14       ... bit positions known to uhci-hcd
1493  *  - endpoint:		bits 15-18      ... bit positions known to uhci-hcd
1494  *  - pipe type:	bits 30-31	(00 = isochronous, 01 = interrupt,
1495  *					 10 = control, 11 = bulk)
1496  *
1497  * Given the device address and endpoint descriptor, pipes are redundant.
1498  */
1499 
1500 /* NOTE:  these are not the standard USB_ENDPOINT_XFER_* values!! */
1501 /* (yet ... they're the values used by usbfs) */
1502 #define PIPE_ISOCHRONOUS		0
1503 #define PIPE_INTERRUPT			1
1504 #define PIPE_CONTROL			2
1505 #define PIPE_BULK			3
1506 
1507 #define usb_pipein(pipe)	((pipe) & USB_DIR_IN)
1508 #define usb_pipeout(pipe)	(!usb_pipein(pipe))
1509 
1510 #define usb_pipedevice(pipe)	(((pipe) >> 8) & 0x7f)
1511 #define usb_pipeendpoint(pipe)	(((pipe) >> 15) & 0xf)
1512 
1513 #define usb_pipetype(pipe)	(((pipe) >> 30) & 3)
1514 #define usb_pipeisoc(pipe)	(usb_pipetype((pipe)) == PIPE_ISOCHRONOUS)
1515 #define usb_pipeint(pipe)	(usb_pipetype((pipe)) == PIPE_INTERRUPT)
1516 #define usb_pipecontrol(pipe)	(usb_pipetype((pipe)) == PIPE_CONTROL)
1517 #define usb_pipebulk(pipe)	(usb_pipetype((pipe)) == PIPE_BULK)
1518 
1519 static inline unsigned int __create_pipe(struct usb_device *dev,
1520 		unsigned int endpoint)
1521 {
1522 	return (dev->devnum << 8) | (endpoint << 15);
1523 }
1524 
1525 /* Create various pipes... */
1526 #define usb_sndctrlpipe(dev, endpoint)	\
1527 	((PIPE_CONTROL << 30) | __create_pipe(dev, endpoint))
1528 #define usb_rcvctrlpipe(dev, endpoint)	\
1529 	((PIPE_CONTROL << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
1530 #define usb_sndisocpipe(dev, endpoint)	\
1531 	((PIPE_ISOCHRONOUS << 30) | __create_pipe(dev, endpoint))
1532 #define usb_rcvisocpipe(dev, endpoint)	\
1533 	((PIPE_ISOCHRONOUS << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
1534 #define usb_sndbulkpipe(dev, endpoint)	\
1535 	((PIPE_BULK << 30) | __create_pipe(dev, endpoint))
1536 #define usb_rcvbulkpipe(dev, endpoint)	\
1537 	((PIPE_BULK << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
1538 #define usb_sndintpipe(dev, endpoint)	\
1539 	((PIPE_INTERRUPT << 30) | __create_pipe(dev, endpoint))
1540 #define usb_rcvintpipe(dev, endpoint)	\
1541 	((PIPE_INTERRUPT << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
1542 
1543 static inline struct usb_host_endpoint *
1544 usb_pipe_endpoint(struct usb_device *dev, unsigned int pipe)
1545 {
1546 	struct usb_host_endpoint **eps;
1547 	eps = usb_pipein(pipe) ? dev->ep_in : dev->ep_out;
1548 	return eps[usb_pipeendpoint(pipe)];
1549 }
1550 
1551 /*-------------------------------------------------------------------------*/
1552 
1553 static inline __u16
1554 usb_maxpacket(struct usb_device *udev, int pipe, int is_out)
1555 {
1556 	struct usb_host_endpoint	*ep;
1557 	unsigned			epnum = usb_pipeendpoint(pipe);
1558 
1559 	if (is_out) {
1560 		WARN_ON(usb_pipein(pipe));
1561 		ep = udev->ep_out[epnum];
1562 	} else {
1563 		WARN_ON(usb_pipeout(pipe));
1564 		ep = udev->ep_in[epnum];
1565 	}
1566 	if (!ep)
1567 		return 0;
1568 
1569 	/* NOTE:  only 0x07ff bits are for packet size... */
1570 	return le16_to_cpu(ep->desc.wMaxPacketSize);
1571 }
1572 
1573 /* ----------------------------------------------------------------------- */
1574 
1575 /* Events from the usb core */
1576 #define USB_DEVICE_ADD		0x0001
1577 #define USB_DEVICE_REMOVE	0x0002
1578 #define USB_BUS_ADD		0x0003
1579 #define USB_BUS_REMOVE		0x0004
1580 extern void usb_register_notify(struct notifier_block *nb);
1581 extern void usb_unregister_notify(struct notifier_block *nb);
1582 
1583 #ifdef DEBUG
1584 #define dbg(format, arg...)						\
1585 	printk(KERN_DEBUG "%s: " format "\n", __FILE__, ##arg)
1586 #else
1587 #define dbg(format, arg...)						\
1588 do {									\
1589 	if (0)								\
1590 		printk(KERN_DEBUG "%s: " format "\n", __FILE__, ##arg); \
1591 } while (0)
1592 #endif
1593 
1594 #define err(format, arg...)					\
1595 	printk(KERN_ERR KBUILD_MODNAME ": " format "\n", ##arg)
1596 
1597 /* debugfs stuff */
1598 extern struct dentry *usb_debug_root;
1599 
1600 #endif  /* __KERNEL__ */
1601 
1602 #endif
1603