xref: /linux/include/linux/usb.h (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_USB_H
3 #define __LINUX_USB_H
4 
5 #include <linux/mod_devicetable.h>
6 #include <linux/usb/ch9.h>
7 
8 #define USB_MAJOR			180
9 #define USB_DEVICE_MAJOR		189
10 
11 
12 #ifdef __KERNEL__
13 
14 #include <linux/errno.h>        /* for -ENODEV */
15 #include <linux/delay.h>	/* for mdelay() */
16 #include <linux/interrupt.h>	/* for in_interrupt() */
17 #include <linux/list.h>		/* for struct list_head */
18 #include <linux/kref.h>		/* for struct kref */
19 #include <linux/device.h>	/* for struct device */
20 #include <linux/fs.h>		/* for struct file_operations */
21 #include <linux/completion.h>	/* for struct completion */
22 #include <linux/sched.h>	/* for current && schedule_timeout */
23 #include <linux/mutex.h>	/* for struct mutex */
24 #include <linux/pm_runtime.h>	/* for runtime PM */
25 
26 struct usb_device;
27 struct usb_driver;
28 
29 /*-------------------------------------------------------------------------*/
30 
31 /*
32  * Host-side wrappers for standard USB descriptors ... these are parsed
33  * from the data provided by devices.  Parsing turns them from a flat
34  * sequence of descriptors into a hierarchy:
35  *
36  *  - devices have one (usually) or more configs;
37  *  - configs have one (often) or more interfaces;
38  *  - interfaces have one (usually) or more settings;
39  *  - each interface setting has zero or (usually) more endpoints.
40  *  - a SuperSpeed endpoint has a companion descriptor
41  *
42  * And there might be other descriptors mixed in with those.
43  *
44  * Devices may also have class-specific or vendor-specific descriptors.
45  */
46 
47 struct ep_device;
48 
49 /**
50  * struct usb_host_endpoint - host-side endpoint descriptor and queue
51  * @desc: descriptor for this endpoint, wMaxPacketSize in native byteorder
52  * @ss_ep_comp: SuperSpeed companion descriptor for this endpoint
53  * @ssp_isoc_ep_comp: SuperSpeedPlus isoc companion descriptor for this endpoint
54  * @urb_list: urbs queued to this endpoint; maintained by usbcore
55  * @hcpriv: for use by HCD; typically holds hardware dma queue head (QH)
56  *	with one or more transfer descriptors (TDs) per urb
57  * @ep_dev: ep_device for sysfs info
58  * @extra: descriptors following this endpoint in the configuration
59  * @extralen: how many bytes of "extra" are valid
60  * @enabled: URBs may be submitted to this endpoint
61  * @streams: number of USB-3 streams allocated on the endpoint
62  *
63  * USB requests are always queued to a given endpoint, identified by a
64  * descriptor within an active interface in a given USB configuration.
65  */
66 struct usb_host_endpoint {
67 	struct usb_endpoint_descriptor		desc;
68 	struct usb_ss_ep_comp_descriptor	ss_ep_comp;
69 	struct usb_ssp_isoc_ep_comp_descriptor	ssp_isoc_ep_comp;
70 	struct list_head		urb_list;
71 	void				*hcpriv;
72 	struct ep_device		*ep_dev;	/* For sysfs info */
73 
74 	unsigned char *extra;   /* Extra descriptors */
75 	int extralen;
76 	int enabled;
77 	int streams;
78 };
79 
80 /* host-side wrapper for one interface setting's parsed descriptors */
81 struct usb_host_interface {
82 	struct usb_interface_descriptor	desc;
83 
84 	int extralen;
85 	unsigned char *extra;   /* Extra descriptors */
86 
87 	/* array of desc.bNumEndpoints endpoints associated with this
88 	 * interface setting.  these will be in no particular order.
89 	 */
90 	struct usb_host_endpoint *endpoint;
91 
92 	char *string;		/* iInterface string, if present */
93 };
94 
95 enum usb_interface_condition {
96 	USB_INTERFACE_UNBOUND = 0,
97 	USB_INTERFACE_BINDING,
98 	USB_INTERFACE_BOUND,
99 	USB_INTERFACE_UNBINDING,
100 };
101 
102 int __must_check
103 usb_find_common_endpoints(struct usb_host_interface *alt,
104 		struct usb_endpoint_descriptor **bulk_in,
105 		struct usb_endpoint_descriptor **bulk_out,
106 		struct usb_endpoint_descriptor **int_in,
107 		struct usb_endpoint_descriptor **int_out);
108 
109 int __must_check
110 usb_find_common_endpoints_reverse(struct usb_host_interface *alt,
111 		struct usb_endpoint_descriptor **bulk_in,
112 		struct usb_endpoint_descriptor **bulk_out,
113 		struct usb_endpoint_descriptor **int_in,
114 		struct usb_endpoint_descriptor **int_out);
115 
116 static inline int __must_check
usb_find_bulk_in_endpoint(struct usb_host_interface * alt,struct usb_endpoint_descriptor ** bulk_in)117 usb_find_bulk_in_endpoint(struct usb_host_interface *alt,
118 		struct usb_endpoint_descriptor **bulk_in)
119 {
120 	return usb_find_common_endpoints(alt, bulk_in, NULL, NULL, NULL);
121 }
122 
123 static inline int __must_check
usb_find_bulk_out_endpoint(struct usb_host_interface * alt,struct usb_endpoint_descriptor ** bulk_out)124 usb_find_bulk_out_endpoint(struct usb_host_interface *alt,
125 		struct usb_endpoint_descriptor **bulk_out)
126 {
127 	return usb_find_common_endpoints(alt, NULL, bulk_out, NULL, NULL);
128 }
129 
130 static inline int __must_check
usb_find_int_in_endpoint(struct usb_host_interface * alt,struct usb_endpoint_descriptor ** int_in)131 usb_find_int_in_endpoint(struct usb_host_interface *alt,
132 		struct usb_endpoint_descriptor **int_in)
133 {
134 	return usb_find_common_endpoints(alt, NULL, NULL, int_in, NULL);
135 }
136 
137 static inline int __must_check
usb_find_int_out_endpoint(struct usb_host_interface * alt,struct usb_endpoint_descriptor ** int_out)138 usb_find_int_out_endpoint(struct usb_host_interface *alt,
139 		struct usb_endpoint_descriptor **int_out)
140 {
141 	return usb_find_common_endpoints(alt, NULL, NULL, NULL, int_out);
142 }
143 
144 static inline int __must_check
usb_find_last_bulk_in_endpoint(struct usb_host_interface * alt,struct usb_endpoint_descriptor ** bulk_in)145 usb_find_last_bulk_in_endpoint(struct usb_host_interface *alt,
146 		struct usb_endpoint_descriptor **bulk_in)
147 {
148 	return usb_find_common_endpoints_reverse(alt, bulk_in, NULL, NULL, NULL);
149 }
150 
151 static inline int __must_check
usb_find_last_bulk_out_endpoint(struct usb_host_interface * alt,struct usb_endpoint_descriptor ** bulk_out)152 usb_find_last_bulk_out_endpoint(struct usb_host_interface *alt,
153 		struct usb_endpoint_descriptor **bulk_out)
154 {
155 	return usb_find_common_endpoints_reverse(alt, NULL, bulk_out, NULL, NULL);
156 }
157 
158 static inline int __must_check
usb_find_last_int_in_endpoint(struct usb_host_interface * alt,struct usb_endpoint_descriptor ** int_in)159 usb_find_last_int_in_endpoint(struct usb_host_interface *alt,
160 		struct usb_endpoint_descriptor **int_in)
161 {
162 	return usb_find_common_endpoints_reverse(alt, NULL, NULL, int_in, NULL);
163 }
164 
165 static inline int __must_check
usb_find_last_int_out_endpoint(struct usb_host_interface * alt,struct usb_endpoint_descriptor ** int_out)166 usb_find_last_int_out_endpoint(struct usb_host_interface *alt,
167 		struct usb_endpoint_descriptor **int_out)
168 {
169 	return usb_find_common_endpoints_reverse(alt, NULL, NULL, NULL, int_out);
170 }
171 
172 enum usb_wireless_status {
173 	USB_WIRELESS_STATUS_NA = 0,
174 	USB_WIRELESS_STATUS_DISCONNECTED,
175 	USB_WIRELESS_STATUS_CONNECTED,
176 };
177 
178 /**
179  * struct usb_interface - what usb device drivers talk to
180  * @altsetting: array of interface structures, one for each alternate
181  *	setting that may be selected.  Each one includes a set of
182  *	endpoint configurations.  They will be in no particular order.
183  * @cur_altsetting: the current altsetting.
184  * @num_altsetting: number of altsettings defined.
185  * @intf_assoc: interface association descriptor
186  * @minor: the minor number assigned to this interface, if this
187  *	interface is bound to a driver that uses the USB major number.
188  *	If this interface does not use the USB major, this field should
189  *	be unused.  The driver should set this value in the probe()
190  *	function of the driver, after it has been assigned a minor
191  *	number from the USB core by calling usb_register_dev().
192  * @condition: binding state of the interface: not bound, binding
193  *	(in probe()), bound to a driver, or unbinding (in disconnect())
194  * @sysfs_files_created: sysfs attributes exist
195  * @ep_devs_created: endpoint child pseudo-devices exist
196  * @unregistering: flag set when the interface is being unregistered
197  * @needs_remote_wakeup: flag set when the driver requires remote-wakeup
198  *	capability during autosuspend.
199  * @needs_altsetting0: flag set when a set-interface request for altsetting 0
200  *	has been deferred.
201  * @needs_binding: flag set when the driver should be re-probed or unbound
202  *	following a reset or suspend operation it doesn't support.
203  * @authorized: This allows to (de)authorize individual interfaces instead
204  *	a whole device in contrast to the device authorization.
205  * @wireless_status: if the USB device uses a receiver/emitter combo, whether
206  *	the emitter is connected.
207  * @wireless_status_work: Used for scheduling wireless status changes
208  *	from atomic context.
209  * @dev: driver model's view of this device
210  * @usb_dev: if an interface is bound to the USB major, this will point
211  *	to the sysfs representation for that device.
212  * @reset_ws: Used for scheduling resets from atomic context.
213  * @resetting_device: USB core reset the device, so use alt setting 0 as
214  *	current; needs bandwidth alloc after reset.
215  *
216  * USB device drivers attach to interfaces on a physical device.  Each
217  * interface encapsulates a single high level function, such as feeding
218  * an audio stream to a speaker or reporting a change in a volume control.
219  * Many USB devices only have one interface.  The protocol used to talk to
220  * an interface's endpoints can be defined in a usb "class" specification,
221  * or by a product's vendor.  The (default) control endpoint is part of
222  * every interface, but is never listed among the interface's descriptors.
223  *
224  * The driver that is bound to the interface can use standard driver model
225  * calls such as dev_get_drvdata() on the dev member of this structure.
226  *
227  * Each interface may have alternate settings.  The initial configuration
228  * of a device sets altsetting 0, but the device driver can change
229  * that setting using usb_set_interface().  Alternate settings are often
230  * used to control the use of periodic endpoints, such as by having
231  * different endpoints use different amounts of reserved USB bandwidth.
232  * All standards-conformant USB devices that use isochronous endpoints
233  * will use them in non-default settings.
234  *
235  * The USB specification says that alternate setting numbers must run from
236  * 0 to one less than the total number of alternate settings.  But some
237  * devices manage to mess this up, and the structures aren't necessarily
238  * stored in numerical order anyhow.  Use usb_altnum_to_altsetting() to
239  * look up an alternate setting in the altsetting array based on its number.
240  */
241 struct usb_interface {
242 	/* array of alternate settings for this interface,
243 	 * stored in no particular order */
244 	struct usb_host_interface *altsetting;
245 
246 	struct usb_host_interface *cur_altsetting;	/* the currently
247 					 * active alternate setting */
248 	unsigned num_altsetting;	/* number of alternate settings */
249 
250 	/* If there is an interface association descriptor then it will list
251 	 * the associated interfaces */
252 	struct usb_interface_assoc_descriptor *intf_assoc;
253 
254 	int minor;			/* minor number this interface is
255 					 * bound to */
256 	enum usb_interface_condition condition;		/* state of binding */
257 	unsigned sysfs_files_created:1;	/* the sysfs attributes exist */
258 	unsigned ep_devs_created:1;	/* endpoint "devices" exist */
259 	unsigned unregistering:1;	/* unregistration is in progress */
260 	unsigned needs_remote_wakeup:1;	/* driver requires remote wakeup */
261 	unsigned needs_altsetting0:1;	/* switch to altsetting 0 is pending */
262 	unsigned needs_binding:1;	/* needs delayed unbind/rebind */
263 	unsigned resetting_device:1;	/* true: bandwidth alloc after reset */
264 	unsigned authorized:1;		/* used for interface authorization */
265 	enum usb_wireless_status wireless_status;
266 	struct work_struct wireless_status_work;
267 
268 	struct device dev;		/* interface specific device info */
269 	struct device *usb_dev;
270 	struct work_struct reset_ws;	/* for resets in atomic context */
271 };
272 
273 #define to_usb_interface(__dev)	container_of_const(__dev, struct usb_interface, dev)
274 
usb_get_intfdata(struct usb_interface * intf)275 static inline void *usb_get_intfdata(struct usb_interface *intf)
276 {
277 	return dev_get_drvdata(&intf->dev);
278 }
279 
280 /**
281  * usb_set_intfdata() - associate driver-specific data with an interface
282  * @intf: USB interface
283  * @data: driver data
284  *
285  * Drivers can use this function in their probe() callbacks to associate
286  * driver-specific data with an interface.
287  *
288  * Note that there is generally no need to clear the driver-data pointer even
289  * if some drivers do so for historical or implementation-specific reasons.
290  */
usb_set_intfdata(struct usb_interface * intf,void * data)291 static inline void usb_set_intfdata(struct usb_interface *intf, void *data)
292 {
293 	dev_set_drvdata(&intf->dev, data);
294 }
295 
296 struct usb_interface *usb_get_intf(struct usb_interface *intf);
297 void usb_put_intf(struct usb_interface *intf);
298 
299 /* Hard limit */
300 #define USB_MAXENDPOINTS	30
301 /* this maximum is arbitrary */
302 #define USB_MAXINTERFACES	32
303 #define USB_MAXIADS		(USB_MAXINTERFACES/2)
304 
305 bool usb_check_bulk_endpoints(
306 		const struct usb_interface *intf, const u8 *ep_addrs);
307 bool usb_check_int_endpoints(
308 		const struct usb_interface *intf, const u8 *ep_addrs);
309 
310 /*
311  * USB Resume Timer: Every Host controller driver should drive the resume
312  * signalling on the bus for the amount of time defined by this macro.
313  *
314  * That way we will have a 'stable' behavior among all HCDs supported by Linux.
315  *
316  * Note that the USB Specification states we should drive resume for *at least*
317  * 20 ms, but it doesn't give an upper bound. This creates two possible
318  * situations which we want to avoid:
319  *
320  * (a) sometimes an msleep(20) might expire slightly before 20 ms, which causes
321  * us to fail USB Electrical Tests, thus failing Certification
322  *
323  * (b) Some (many) devices actually need more than 20 ms of resume signalling,
324  * and while we can argue that's against the USB Specification, we don't have
325  * control over which devices a certification laboratory will be using for
326  * certification. If CertLab uses a device which was tested against Windows and
327  * that happens to have relaxed resume signalling rules, we might fall into
328  * situations where we fail interoperability and electrical tests.
329  *
330  * In order to avoid both conditions, we're using a 40 ms resume timeout, which
331  * should cope with both LPJ calibration errors and devices not following every
332  * detail of the USB Specification.
333  */
334 #define USB_RESUME_TIMEOUT	40 /* ms */
335 
336 /**
337  * struct usb_interface_cache - long-term representation of a device interface
338  * @num_altsetting: number of altsettings defined.
339  * @ref: reference counter.
340  * @altsetting: variable-length array of interface structures, one for
341  *	each alternate setting that may be selected.  Each one includes a
342  *	set of endpoint configurations.  They will be in no particular order.
343  *
344  * These structures persist for the lifetime of a usb_device, unlike
345  * struct usb_interface (which persists only as long as its configuration
346  * is installed).  The altsetting arrays can be accessed through these
347  * structures at any time, permitting comparison of configurations and
348  * providing support for the /sys/kernel/debug/usb/devices pseudo-file.
349  */
350 struct usb_interface_cache {
351 	unsigned num_altsetting;	/* number of alternate settings */
352 	struct kref ref;		/* reference counter */
353 
354 	/* variable-length array of alternate settings for this interface,
355 	 * stored in no particular order */
356 	struct usb_host_interface altsetting[];
357 };
358 #define	ref_to_usb_interface_cache(r) \
359 		container_of(r, struct usb_interface_cache, ref)
360 #define	altsetting_to_usb_interface_cache(a) \
361 		container_of(a, struct usb_interface_cache, altsetting[0])
362 
363 /**
364  * struct usb_host_config - representation of a device's configuration
365  * @desc: the device's configuration descriptor.
366  * @string: pointer to the cached version of the iConfiguration string, if
367  *	present for this configuration.
368  * @intf_assoc: list of any interface association descriptors in this config
369  * @interface: array of pointers to usb_interface structures, one for each
370  *	interface in the configuration.  The number of interfaces is stored
371  *	in desc.bNumInterfaces.  These pointers are valid only while the
372  *	configuration is active.
373  * @intf_cache: array of pointers to usb_interface_cache structures, one
374  *	for each interface in the configuration.  These structures exist
375  *	for the entire life of the device.
376  * @extra: pointer to buffer containing all extra descriptors associated
377  *	with this configuration (those preceding the first interface
378  *	descriptor).
379  * @extralen: length of the extra descriptors buffer.
380  *
381  * USB devices may have multiple configurations, but only one can be active
382  * at any time.  Each encapsulates a different operational environment;
383  * for example, a dual-speed device would have separate configurations for
384  * full-speed and high-speed operation.  The number of configurations
385  * available is stored in the device descriptor as bNumConfigurations.
386  *
387  * A configuration can contain multiple interfaces.  Each corresponds to
388  * a different function of the USB device, and all are available whenever
389  * the configuration is active.  The USB standard says that interfaces
390  * are supposed to be numbered from 0 to desc.bNumInterfaces-1, but a lot
391  * of devices get this wrong.  In addition, the interface array is not
392  * guaranteed to be sorted in numerical order.  Use usb_ifnum_to_if() to
393  * look up an interface entry based on its number.
394  *
395  * Device drivers should not attempt to activate configurations.  The choice
396  * of which configuration to install is a policy decision based on such
397  * considerations as available power, functionality provided, and the user's
398  * desires (expressed through userspace tools).  However, drivers can call
399  * usb_reset_configuration() to reinitialize the current configuration and
400  * all its interfaces.
401  */
402 struct usb_host_config {
403 	struct usb_config_descriptor	desc;
404 
405 	char *string;		/* iConfiguration string, if present */
406 
407 	/* List of any Interface Association Descriptors in this
408 	 * configuration. */
409 	struct usb_interface_assoc_descriptor *intf_assoc[USB_MAXIADS];
410 
411 	/* the interfaces associated with this configuration,
412 	 * stored in no particular order */
413 	struct usb_interface *interface[USB_MAXINTERFACES];
414 
415 	/* Interface information available even when this is not the
416 	 * active configuration */
417 	struct usb_interface_cache *intf_cache[USB_MAXINTERFACES];
418 
419 	unsigned char *extra;   /* Extra descriptors */
420 	int extralen;
421 };
422 
423 /* USB2.0 and USB3.0 device BOS descriptor set */
424 struct usb_host_bos {
425 	struct usb_bos_descriptor	*desc;
426 
427 	struct usb_ext_cap_descriptor	*ext_cap;
428 	struct usb_ss_cap_descriptor	*ss_cap;
429 	struct usb_ssp_cap_descriptor	*ssp_cap;
430 	struct usb_ss_container_id_descriptor	*ss_id;
431 	struct usb_ptm_cap_descriptor	*ptm_cap;
432 };
433 
434 int __usb_get_extra_descriptor(char *buffer, unsigned size,
435 	unsigned char type, void **ptr, size_t min);
436 #define usb_get_extra_descriptor(ifpoint, type, ptr) \
437 				__usb_get_extra_descriptor((ifpoint)->extra, \
438 				(ifpoint)->extralen, \
439 				type, (void **)ptr, sizeof(**(ptr)))
440 
441 /* ----------------------------------------------------------------------- */
442 
443 /*
444  * Allocated per bus (tree of devices) we have:
445  */
446 struct usb_bus {
447 	struct device *controller;	/* host side hardware */
448 	struct device *sysdev;		/* as seen from firmware or bus */
449 	int busnum;			/* Bus number (in order of reg) */
450 	const char *bus_name;		/* stable id (PCI slot_name etc) */
451 	u8 uses_pio_for_control;	/*
452 					 * Does the host controller use PIO
453 					 * for control transfers?
454 					 */
455 	u8 otg_port;			/* 0, or number of OTG/HNP port */
456 	unsigned is_b_host:1;		/* true during some HNP roleswitches */
457 	unsigned b_hnp_enable:1;	/* OTG: did A-Host enable HNP? */
458 	unsigned no_stop_on_short:1;    /*
459 					 * Quirk: some controllers don't stop
460 					 * the ep queue on a short transfer
461 					 * with the URB_SHORT_NOT_OK flag set.
462 					 */
463 	unsigned no_sg_constraint:1;	/* no sg constraint */
464 	unsigned sg_tablesize;		/* 0 or largest number of sg list entries */
465 
466 	int devnum_next;		/* Next open device number in
467 					 * round-robin allocation */
468 	struct mutex devnum_next_mutex; /* devnum_next mutex */
469 
470 	DECLARE_BITMAP(devmap, 128);	/* USB device number allocation bitmap */
471 	struct usb_device *root_hub;	/* Root hub */
472 	struct usb_bus *hs_companion;	/* Companion EHCI bus, if any */
473 
474 	int bandwidth_allocated;	/* on this bus: how much of the time
475 					 * reserved for periodic (intr/iso)
476 					 * requests is used, on average?
477 					 * Units: microseconds/frame.
478 					 * Limits: Full/low speed reserve 90%,
479 					 * while high speed reserves 80%.
480 					 */
481 	int bandwidth_int_reqs;		/* number of Interrupt requests */
482 	int bandwidth_isoc_reqs;	/* number of Isoc. requests */
483 
484 	unsigned resuming_ports;	/* bit array: resuming root-hub ports */
485 
486 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE)
487 	struct mon_bus *mon_bus;	/* non-null when associated */
488 	int monitored;			/* non-zero when monitored */
489 #endif
490 };
491 
492 struct usb_dev_state;
493 
494 /* ----------------------------------------------------------------------- */
495 
496 struct usb_tt;
497 
498 enum usb_link_tunnel_mode {
499 	USB_LINK_UNKNOWN = 0,
500 	USB_LINK_NATIVE,
501 	USB_LINK_TUNNELED,
502 };
503 
504 enum usb_port_connect_type {
505 	USB_PORT_CONNECT_TYPE_UNKNOWN = 0,
506 	USB_PORT_CONNECT_TYPE_HOT_PLUG,
507 	USB_PORT_CONNECT_TYPE_HARD_WIRED,
508 	USB_PORT_NOT_USED,
509 };
510 
511 /*
512  * USB port quirks.
513  */
514 
515 /* For the given port, prefer the old (faster) enumeration scheme. */
516 #define USB_PORT_QUIRK_OLD_SCHEME	BIT(0)
517 
518 /* Decrease TRSTRCY to 10ms during device enumeration. */
519 #define USB_PORT_QUIRK_FAST_ENUM	BIT(1)
520 
521 /*
522  * USB 2.0 Link Power Management (LPM) parameters.
523  */
524 struct usb2_lpm_parameters {
525 	/* Best effort service latency indicate how long the host will drive
526 	 * resume on an exit from L1.
527 	 */
528 	unsigned int besl;
529 
530 	/* Timeout value in microseconds for the L1 inactivity (LPM) timer.
531 	 * When the timer counts to zero, the parent hub will initiate a LPM
532 	 * transition to L1.
533 	 */
534 	int timeout;
535 };
536 
537 /*
538  * USB 3.0 Link Power Management (LPM) parameters.
539  *
540  * PEL and SEL are USB 3.0 Link PM latencies for device-initiated LPM exit.
541  * MEL is the USB 3.0 Link PM latency for host-initiated LPM exit.
542  * All three are stored in nanoseconds.
543  */
544 struct usb3_lpm_parameters {
545 	/*
546 	 * Maximum exit latency (MEL) for the host to send a packet to the
547 	 * device (either a Ping for isoc endpoints, or a data packet for
548 	 * interrupt endpoints), the hubs to decode the packet, and for all hubs
549 	 * in the path to transition the links to U0.
550 	 */
551 	unsigned int mel;
552 	/*
553 	 * Maximum exit latency for a device-initiated LPM transition to bring
554 	 * all links into U0.  Abbreviated as "PEL" in section 9.4.12 of the USB
555 	 * 3.0 spec, with no explanation of what "P" stands for.  "Path"?
556 	 */
557 	unsigned int pel;
558 
559 	/*
560 	 * The System Exit Latency (SEL) includes PEL, and three other
561 	 * latencies.  After a device initiates a U0 transition, it will take
562 	 * some time from when the device sends the ERDY to when it will finally
563 	 * receive the data packet.  Basically, SEL should be the worse-case
564 	 * latency from when a device starts initiating a U0 transition to when
565 	 * it will get data.
566 	 */
567 	unsigned int sel;
568 	/*
569 	 * The idle timeout value that is currently programmed into the parent
570 	 * hub for this device.  When the timer counts to zero, the parent hub
571 	 * will initiate an LPM transition to either U1 or U2.
572 	 */
573 	int timeout;
574 };
575 
576 /**
577  * struct usb_device - kernel's representation of a USB device
578  * @devnum: device number; address on a USB bus
579  * @devpath: device ID string for use in messages (e.g., /port/...)
580  * @route: tree topology hex string for use with xHCI
581  * @state: device state: configured, not attached, etc.
582  * @speed: device speed: high/full/low (or error)
583  * @rx_lanes: number of rx lanes in use, USB 3.2 adds dual-lane support
584  * @tx_lanes: number of tx lanes in use, USB 3.2 adds dual-lane support
585  * @ssp_rate: SuperSpeed Plus phy signaling rate and lane count
586  * @tt: Transaction Translator info; used with low/full speed dev, highspeed hub
587  * @ttport: device port on that tt hub
588  * @toggle: one bit for each endpoint, with ([0] = IN, [1] = OUT) endpoints
589  * @parent: our hub, unless we're the root
590  * @bus: bus we're part of
591  * @ep0: endpoint 0 data (default control pipe)
592  * @dev: generic device interface
593  * @descriptor: USB device descriptor
594  * @bos: USB device BOS descriptor set
595  * @config: all of the device's configs
596  * @actconfig: the active configuration
597  * @ep_in: array of IN endpoints
598  * @ep_out: array of OUT endpoints
599  * @rawdescriptors: raw descriptors for each config
600  * @bus_mA: Current available from the bus
601  * @portnum: parent port number (origin 1)
602  * @level: number of USB hub ancestors
603  * @devaddr: device address, XHCI: assigned by HW, others: same as devnum
604  * @can_submit: URBs may be submitted
605  * @persist_enabled:  USB_PERSIST enabled for this device
606  * @reset_in_progress: the device is being reset
607  * @have_langid: whether string_langid is valid
608  * @authorized: policy has said we can use it;
609  *	(user space) policy determines if we authorize this device to be
610  *	used or not. By default, wired USB devices are authorized.
611  *	WUSB devices are not, until we authorize them from user space.
612  *	FIXME -- complete doc
613  * @authenticated: Crypto authentication passed
614  * @tunnel_mode: Connection native or tunneled over USB4
615  * @lpm_capable: device supports LPM
616  * @lpm_devinit_allow: Allow USB3 device initiated LPM, exit latency is in range
617  * @usb2_hw_lpm_capable: device can perform USB2 hardware LPM
618  * @usb2_hw_lpm_besl_capable: device can perform USB2 hardware BESL LPM
619  * @usb2_hw_lpm_enabled: USB2 hardware LPM is enabled
620  * @usb2_hw_lpm_allowed: Userspace allows USB 2.0 LPM to be enabled
621  * @usb3_lpm_u1_enabled: USB3 hardware U1 LPM enabled
622  * @usb3_lpm_u2_enabled: USB3 hardware U2 LPM enabled
623  * @string_langid: language ID for strings
624  * @product: iProduct string, if present (static)
625  * @manufacturer: iManufacturer string, if present (static)
626  * @serial: iSerialNumber string, if present (static)
627  * @filelist: usbfs files that are open to this device
628  * @maxchild: number of ports if hub
629  * @quirks: quirks of the whole device
630  * @urbnum: number of URBs submitted for the whole device
631  * @active_duration: total time device is not suspended
632  * @connect_time: time device was first connected
633  * @do_remote_wakeup:  remote wakeup should be enabled
634  * @reset_resume: needs reset instead of resume
635  * @port_is_suspended: the upstream port is suspended (L2 or U3)
636  * @slot_id: Slot ID assigned by xHCI
637  * @l1_params: best effor service latency for USB2 L1 LPM state, and L1 timeout.
638  * @u1_params: exit latencies for USB3 U1 LPM state, and hub-initiated timeout.
639  * @u2_params: exit latencies for USB3 U2 LPM state, and hub-initiated timeout.
640  * @lpm_disable_count: Ref count used by usb_disable_lpm() and usb_enable_lpm()
641  *	to keep track of the number of functions that require USB 3.0 Link Power
642  *	Management to be disabled for this usb_device.  This count should only
643  *	be manipulated by those functions, with the bandwidth_mutex is held.
644  * @hub_delay: cached value consisting of:
645  *	parent->hub_delay + wHubDelay + tTPTransmissionDelay (40ns)
646  *	Will be used as wValue for SetIsochDelay requests.
647  * @use_generic_driver: ask driver core to reprobe using the generic driver.
648  *
649  * Notes:
650  * Usbcore drivers should not set usbdev->state directly.  Instead use
651  * usb_set_device_state().
652  */
653 struct usb_device {
654 	int		devnum;
655 	char		devpath[16];
656 	u32		route;
657 	enum usb_device_state	state;
658 	enum usb_device_speed	speed;
659 	unsigned int		rx_lanes;
660 	unsigned int		tx_lanes;
661 	enum usb_ssp_rate	ssp_rate;
662 
663 	struct usb_tt	*tt;
664 	int		ttport;
665 
666 	unsigned int toggle[2];
667 
668 	struct usb_device *parent;
669 	struct usb_bus *bus;
670 	struct usb_host_endpoint ep0;
671 
672 	struct device dev;
673 
674 	struct usb_device_descriptor descriptor;
675 	struct usb_host_bos *bos;
676 	struct usb_host_config *config;
677 
678 	struct usb_host_config *actconfig;
679 	struct usb_host_endpoint *ep_in[16];
680 	struct usb_host_endpoint *ep_out[16];
681 
682 	char **rawdescriptors;
683 
684 	unsigned short bus_mA;
685 	u8 portnum;
686 	u8 level;
687 	u8 devaddr;
688 
689 	unsigned can_submit:1;
690 	unsigned persist_enabled:1;
691 	unsigned reset_in_progress:1;
692 	unsigned have_langid:1;
693 	unsigned authorized:1;
694 	unsigned authenticated:1;
695 	unsigned lpm_capable:1;
696 	unsigned lpm_devinit_allow:1;
697 	unsigned usb2_hw_lpm_capable:1;
698 	unsigned usb2_hw_lpm_besl_capable:1;
699 	unsigned usb2_hw_lpm_enabled:1;
700 	unsigned usb2_hw_lpm_allowed:1;
701 	unsigned usb3_lpm_u1_enabled:1;
702 	unsigned usb3_lpm_u2_enabled:1;
703 	int string_langid;
704 
705 	/* static strings from the device */
706 	char *product;
707 	char *manufacturer;
708 	char *serial;
709 
710 	struct list_head filelist;
711 
712 	int maxchild;
713 
714 	u32 quirks;
715 	atomic_t urbnum;
716 
717 	unsigned long active_duration;
718 
719 	unsigned long connect_time;
720 
721 	unsigned do_remote_wakeup:1;
722 	unsigned reset_resume:1;
723 	unsigned port_is_suspended:1;
724 	enum usb_link_tunnel_mode tunnel_mode;
725 
726 	int slot_id;
727 	struct usb2_lpm_parameters l1_params;
728 	struct usb3_lpm_parameters u1_params;
729 	struct usb3_lpm_parameters u2_params;
730 	unsigned lpm_disable_count;
731 
732 	u16 hub_delay;
733 	unsigned use_generic_driver:1;
734 };
735 
736 #define to_usb_device(__dev)	container_of_const(__dev, struct usb_device, dev)
737 
__intf_to_usbdev(struct usb_interface * intf)738 static inline struct usb_device *__intf_to_usbdev(struct usb_interface *intf)
739 {
740 	return to_usb_device(intf->dev.parent);
741 }
__intf_to_usbdev_const(const struct usb_interface * intf)742 static inline const struct usb_device *__intf_to_usbdev_const(const struct usb_interface *intf)
743 {
744 	return to_usb_device((const struct device *)intf->dev.parent);
745 }
746 
747 #define interface_to_usbdev(intf)					\
748 	_Generic((intf),						\
749 		 const struct usb_interface *: __intf_to_usbdev_const,	\
750 		 struct usb_interface *: __intf_to_usbdev)(intf)
751 
752 extern struct usb_device *usb_get_dev(struct usb_device *dev);
753 extern void usb_put_dev(struct usb_device *dev);
754 extern struct usb_device *usb_hub_find_child(struct usb_device *hdev,
755 	int port1);
756 
757 /**
758  * usb_hub_for_each_child - iterate over all child devices on the hub
759  * @hdev:  USB device belonging to the usb hub
760  * @port1: portnum associated with child device
761  * @child: child device pointer
762  */
763 #define usb_hub_for_each_child(hdev, port1, child) \
764 	for (port1 = 1,	child =	usb_hub_find_child(hdev, port1); \
765 			port1 <= hdev->maxchild; \
766 			child = usb_hub_find_child(hdev, ++port1)) \
767 		if (!child) continue; else
768 
769 /* USB device locking */
770 #define usb_lock_device(udev)			device_lock(&(udev)->dev)
771 #define usb_unlock_device(udev)			device_unlock(&(udev)->dev)
772 #define usb_lock_device_interruptible(udev)	device_lock_interruptible(&(udev)->dev)
773 #define usb_trylock_device(udev)		device_trylock(&(udev)->dev)
774 extern int usb_lock_device_for_reset(struct usb_device *udev,
775 				     const struct usb_interface *iface);
776 
777 /* USB port reset for device reinitialization */
778 extern int usb_reset_device(struct usb_device *dev);
779 extern void usb_queue_reset_device(struct usb_interface *dev);
780 
781 extern struct device *usb_intf_get_dma_device(struct usb_interface *intf);
782 
783 #ifdef CONFIG_ACPI
784 extern int usb_acpi_set_power_state(struct usb_device *hdev, int index,
785 	bool enable);
786 extern bool usb_acpi_power_manageable(struct usb_device *hdev, int index);
787 extern int usb_acpi_port_lpm_incapable(struct usb_device *hdev, int index);
788 #else
usb_acpi_set_power_state(struct usb_device * hdev,int index,bool enable)789 static inline int usb_acpi_set_power_state(struct usb_device *hdev, int index,
790 	bool enable) { return 0; }
usb_acpi_power_manageable(struct usb_device * hdev,int index)791 static inline bool usb_acpi_power_manageable(struct usb_device *hdev, int index)
792 	{ return true; }
usb_acpi_port_lpm_incapable(struct usb_device * hdev,int index)793 static inline int usb_acpi_port_lpm_incapable(struct usb_device *hdev, int index)
794 	{ return 0; }
795 #endif
796 
797 /* USB autosuspend and autoresume */
798 #ifdef CONFIG_PM
799 extern void usb_enable_autosuspend(struct usb_device *udev);
800 extern void usb_disable_autosuspend(struct usb_device *udev);
801 
802 extern int usb_autopm_get_interface(struct usb_interface *intf);
803 extern void usb_autopm_put_interface(struct usb_interface *intf);
804 extern int usb_autopm_get_interface_async(struct usb_interface *intf);
805 extern void usb_autopm_put_interface_async(struct usb_interface *intf);
806 extern void usb_autopm_get_interface_no_resume(struct usb_interface *intf);
807 extern void usb_autopm_put_interface_no_suspend(struct usb_interface *intf);
808 
usb_mark_last_busy(struct usb_device * udev)809 static inline void usb_mark_last_busy(struct usb_device *udev)
810 {
811 	pm_runtime_mark_last_busy(&udev->dev);
812 }
813 
814 #else
815 
usb_enable_autosuspend(struct usb_device * udev)816 static inline int usb_enable_autosuspend(struct usb_device *udev)
817 { return 0; }
usb_disable_autosuspend(struct usb_device * udev)818 static inline int usb_disable_autosuspend(struct usb_device *udev)
819 { return 0; }
820 
usb_autopm_get_interface(struct usb_interface * intf)821 static inline int usb_autopm_get_interface(struct usb_interface *intf)
822 { return 0; }
usb_autopm_get_interface_async(struct usb_interface * intf)823 static inline int usb_autopm_get_interface_async(struct usb_interface *intf)
824 { return 0; }
825 
usb_autopm_put_interface(struct usb_interface * intf)826 static inline void usb_autopm_put_interface(struct usb_interface *intf)
827 { }
usb_autopm_put_interface_async(struct usb_interface * intf)828 static inline void usb_autopm_put_interface_async(struct usb_interface *intf)
829 { }
usb_autopm_get_interface_no_resume(struct usb_interface * intf)830 static inline void usb_autopm_get_interface_no_resume(
831 		struct usb_interface *intf)
832 { }
usb_autopm_put_interface_no_suspend(struct usb_interface * intf)833 static inline void usb_autopm_put_interface_no_suspend(
834 		struct usb_interface *intf)
835 { }
usb_mark_last_busy(struct usb_device * udev)836 static inline void usb_mark_last_busy(struct usb_device *udev)
837 { }
838 #endif
839 
840 extern int usb_disable_lpm(struct usb_device *udev);
841 extern void usb_enable_lpm(struct usb_device *udev);
842 /* Same as above, but these functions lock/unlock the bandwidth_mutex. */
843 extern int usb_unlocked_disable_lpm(struct usb_device *udev);
844 extern void usb_unlocked_enable_lpm(struct usb_device *udev);
845 
846 extern int usb_disable_ltm(struct usb_device *udev);
847 extern void usb_enable_ltm(struct usb_device *udev);
848 
usb_device_supports_ltm(struct usb_device * udev)849 static inline bool usb_device_supports_ltm(struct usb_device *udev)
850 {
851 	if (udev->speed < USB_SPEED_SUPER || !udev->bos || !udev->bos->ss_cap)
852 		return false;
853 	return udev->bos->ss_cap->bmAttributes & USB_LTM_SUPPORT;
854 }
855 
usb_device_no_sg_constraint(struct usb_device * udev)856 static inline bool usb_device_no_sg_constraint(struct usb_device *udev)
857 {
858 	return udev && udev->bus && udev->bus->no_sg_constraint;
859 }
860 
861 
862 /*-------------------------------------------------------------------------*/
863 
864 /* for drivers using iso endpoints */
865 extern int usb_get_current_frame_number(struct usb_device *usb_dev);
866 
867 /* Sets up a group of bulk endpoints to support multiple stream IDs. */
868 extern int usb_alloc_streams(struct usb_interface *interface,
869 		struct usb_host_endpoint **eps, unsigned int num_eps,
870 		unsigned int num_streams, gfp_t mem_flags);
871 
872 /* Reverts a group of bulk endpoints back to not using stream IDs. */
873 extern int usb_free_streams(struct usb_interface *interface,
874 		struct usb_host_endpoint **eps, unsigned int num_eps,
875 		gfp_t mem_flags);
876 
877 /* used these for multi-interface device registration */
878 extern int usb_driver_claim_interface(struct usb_driver *driver,
879 			struct usb_interface *iface, void *data);
880 
881 /**
882  * usb_interface_claimed - returns true iff an interface is claimed
883  * @iface: the interface being checked
884  *
885  * Return: %true (nonzero) iff the interface is claimed, else %false
886  * (zero).
887  *
888  * Note:
889  * Callers must own the driver model's usb bus readlock.  So driver
890  * probe() entries don't need extra locking, but other call contexts
891  * may need to explicitly claim that lock.
892  *
893  */
usb_interface_claimed(struct usb_interface * iface)894 static inline int usb_interface_claimed(struct usb_interface *iface)
895 {
896 	return (iface->dev.driver != NULL);
897 }
898 
899 extern void usb_driver_release_interface(struct usb_driver *driver,
900 			struct usb_interface *iface);
901 
902 int usb_set_wireless_status(struct usb_interface *iface,
903 			enum usb_wireless_status status);
904 
905 const struct usb_device_id *usb_match_id(struct usb_interface *interface,
906 					 const struct usb_device_id *id);
907 extern int usb_match_one_id(struct usb_interface *interface,
908 			    const struct usb_device_id *id);
909 
910 extern int usb_for_each_dev(void *data, int (*fn)(struct usb_device *, void *));
911 extern struct usb_interface *usb_find_interface(struct usb_driver *drv,
912 		int minor);
913 extern struct usb_interface *usb_ifnum_to_if(const struct usb_device *dev,
914 		unsigned ifnum);
915 extern struct usb_host_interface *usb_altnum_to_altsetting(
916 		const struct usb_interface *intf, unsigned int altnum);
917 extern struct usb_host_interface *usb_find_alt_setting(
918 		struct usb_host_config *config,
919 		unsigned int iface_num,
920 		unsigned int alt_num);
921 
922 /* port claiming functions */
923 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
924 		struct usb_dev_state *owner);
925 int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
926 		struct usb_dev_state *owner);
927 
928 /**
929  * usb_make_path - returns stable device path in the usb tree
930  * @dev: the device whose path is being constructed
931  * @buf: where to put the string
932  * @size: how big is "buf"?
933  *
934  * Return: Length of the string (> 0) or negative if size was too small.
935  *
936  * Note:
937  * This identifier is intended to be "stable", reflecting physical paths in
938  * hardware such as physical bus addresses for host controllers or ports on
939  * USB hubs.  That makes it stay the same until systems are physically
940  * reconfigured, by re-cabling a tree of USB devices or by moving USB host
941  * controllers.  Adding and removing devices, including virtual root hubs
942  * in host controller driver modules, does not change these path identifiers;
943  * neither does rebooting or re-enumerating.  These are more useful identifiers
944  * than changeable ("unstable") ones like bus numbers or device addresses.
945  *
946  * With a partial exception for devices connected to USB 2.0 root hubs, these
947  * identifiers are also predictable.  So long as the device tree isn't changed,
948  * plugging any USB device into a given hub port always gives it the same path.
949  * Because of the use of "companion" controllers, devices connected to ports on
950  * USB 2.0 root hubs (EHCI host controllers) will get one path ID if they are
951  * high speed, and a different one if they are full or low speed.
952  */
usb_make_path(struct usb_device * dev,char * buf,size_t size)953 static inline int usb_make_path(struct usb_device *dev, char *buf, size_t size)
954 {
955 	int actual;
956 	actual = snprintf(buf, size, "usb-%s-%s", dev->bus->bus_name,
957 			  dev->devpath);
958 	return (actual >= (int)size) ? -1 : actual;
959 }
960 
961 /*-------------------------------------------------------------------------*/
962 
963 #define USB_DEVICE_ID_MATCH_DEVICE \
964 		(USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT)
965 #define USB_DEVICE_ID_MATCH_DEV_RANGE \
966 		(USB_DEVICE_ID_MATCH_DEV_LO | USB_DEVICE_ID_MATCH_DEV_HI)
967 #define USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION \
968 		(USB_DEVICE_ID_MATCH_DEVICE | USB_DEVICE_ID_MATCH_DEV_RANGE)
969 #define USB_DEVICE_ID_MATCH_DEV_INFO \
970 		(USB_DEVICE_ID_MATCH_DEV_CLASS | \
971 		USB_DEVICE_ID_MATCH_DEV_SUBCLASS | \
972 		USB_DEVICE_ID_MATCH_DEV_PROTOCOL)
973 #define USB_DEVICE_ID_MATCH_INT_INFO \
974 		(USB_DEVICE_ID_MATCH_INT_CLASS | \
975 		USB_DEVICE_ID_MATCH_INT_SUBCLASS | \
976 		USB_DEVICE_ID_MATCH_INT_PROTOCOL)
977 
978 /**
979  * USB_DEVICE - macro used to describe a specific usb device
980  * @vend: the 16 bit USB Vendor ID
981  * @prod: the 16 bit USB Product ID
982  *
983  * This macro is used to create a struct usb_device_id that matches a
984  * specific device.
985  */
986 #define USB_DEVICE(vend, prod) \
987 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE, \
988 	.idVendor = (vend), \
989 	.idProduct = (prod)
990 /**
991  * USB_DEVICE_VER - describe a specific usb device with a version range
992  * @vend: the 16 bit USB Vendor ID
993  * @prod: the 16 bit USB Product ID
994  * @lo: the bcdDevice_lo value
995  * @hi: the bcdDevice_hi value
996  *
997  * This macro is used to create a struct usb_device_id that matches a
998  * specific device, with a version range.
999  */
1000 #define USB_DEVICE_VER(vend, prod, lo, hi) \
1001 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE_AND_VERSION, \
1002 	.idVendor = (vend), \
1003 	.idProduct = (prod), \
1004 	.bcdDevice_lo = (lo), \
1005 	.bcdDevice_hi = (hi)
1006 
1007 /**
1008  * USB_DEVICE_INTERFACE_CLASS - describe a usb device with a specific interface class
1009  * @vend: the 16 bit USB Vendor ID
1010  * @prod: the 16 bit USB Product ID
1011  * @cl: bInterfaceClass value
1012  *
1013  * This macro is used to create a struct usb_device_id that matches a
1014  * specific interface class of devices.
1015  */
1016 #define USB_DEVICE_INTERFACE_CLASS(vend, prod, cl) \
1017 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
1018 		       USB_DEVICE_ID_MATCH_INT_CLASS, \
1019 	.idVendor = (vend), \
1020 	.idProduct = (prod), \
1021 	.bInterfaceClass = (cl)
1022 
1023 /**
1024  * USB_DEVICE_INTERFACE_PROTOCOL - describe a usb device with a specific interface protocol
1025  * @vend: the 16 bit USB Vendor ID
1026  * @prod: the 16 bit USB Product ID
1027  * @pr: bInterfaceProtocol value
1028  *
1029  * This macro is used to create a struct usb_device_id that matches a
1030  * specific interface protocol of devices.
1031  */
1032 #define USB_DEVICE_INTERFACE_PROTOCOL(vend, prod, pr) \
1033 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
1034 		       USB_DEVICE_ID_MATCH_INT_PROTOCOL, \
1035 	.idVendor = (vend), \
1036 	.idProduct = (prod), \
1037 	.bInterfaceProtocol = (pr)
1038 
1039 /**
1040  * USB_DEVICE_INTERFACE_NUMBER - describe a usb device with a specific interface number
1041  * @vend: the 16 bit USB Vendor ID
1042  * @prod: the 16 bit USB Product ID
1043  * @num: bInterfaceNumber value
1044  *
1045  * This macro is used to create a struct usb_device_id that matches a
1046  * specific interface number of devices.
1047  */
1048 #define USB_DEVICE_INTERFACE_NUMBER(vend, prod, num) \
1049 	.match_flags = USB_DEVICE_ID_MATCH_DEVICE | \
1050 		       USB_DEVICE_ID_MATCH_INT_NUMBER, \
1051 	.idVendor = (vend), \
1052 	.idProduct = (prod), \
1053 	.bInterfaceNumber = (num)
1054 
1055 /**
1056  * USB_DEVICE_INFO - macro used to describe a class of usb devices
1057  * @cl: bDeviceClass value
1058  * @sc: bDeviceSubClass value
1059  * @pr: bDeviceProtocol value
1060  *
1061  * This macro is used to create a struct usb_device_id that matches a
1062  * specific class of devices.
1063  */
1064 #define USB_DEVICE_INFO(cl, sc, pr) \
1065 	.match_flags = USB_DEVICE_ID_MATCH_DEV_INFO, \
1066 	.bDeviceClass = (cl), \
1067 	.bDeviceSubClass = (sc), \
1068 	.bDeviceProtocol = (pr)
1069 
1070 /**
1071  * USB_INTERFACE_INFO - macro used to describe a class of usb interfaces
1072  * @cl: bInterfaceClass value
1073  * @sc: bInterfaceSubClass value
1074  * @pr: bInterfaceProtocol value
1075  *
1076  * This macro is used to create a struct usb_device_id that matches a
1077  * specific class of interfaces.
1078  */
1079 #define USB_INTERFACE_INFO(cl, sc, pr) \
1080 	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO, \
1081 	.bInterfaceClass = (cl), \
1082 	.bInterfaceSubClass = (sc), \
1083 	.bInterfaceProtocol = (pr)
1084 
1085 /**
1086  * USB_DEVICE_AND_INTERFACE_INFO - describe a specific usb device with a class of usb interfaces
1087  * @vend: the 16 bit USB Vendor ID
1088  * @prod: the 16 bit USB Product ID
1089  * @cl: bInterfaceClass value
1090  * @sc: bInterfaceSubClass value
1091  * @pr: bInterfaceProtocol value
1092  *
1093  * This macro is used to create a struct usb_device_id that matches a
1094  * specific device with a specific class of interfaces.
1095  *
1096  * This is especially useful when explicitly matching devices that have
1097  * vendor specific bDeviceClass values, but standards-compliant interfaces.
1098  */
1099 #define USB_DEVICE_AND_INTERFACE_INFO(vend, prod, cl, sc, pr) \
1100 	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO \
1101 		| USB_DEVICE_ID_MATCH_DEVICE, \
1102 	.idVendor = (vend), \
1103 	.idProduct = (prod), \
1104 	.bInterfaceClass = (cl), \
1105 	.bInterfaceSubClass = (sc), \
1106 	.bInterfaceProtocol = (pr)
1107 
1108 /**
1109  * USB_VENDOR_AND_INTERFACE_INFO - describe a specific usb vendor with a class of usb interfaces
1110  * @vend: the 16 bit USB Vendor ID
1111  * @cl: bInterfaceClass value
1112  * @sc: bInterfaceSubClass value
1113  * @pr: bInterfaceProtocol value
1114  *
1115  * This macro is used to create a struct usb_device_id that matches a
1116  * specific vendor with a specific class of interfaces.
1117  *
1118  * This is especially useful when explicitly matching devices that have
1119  * vendor specific bDeviceClass values, but standards-compliant interfaces.
1120  */
1121 #define USB_VENDOR_AND_INTERFACE_INFO(vend, cl, sc, pr) \
1122 	.match_flags = USB_DEVICE_ID_MATCH_INT_INFO \
1123 		| USB_DEVICE_ID_MATCH_VENDOR, \
1124 	.idVendor = (vend), \
1125 	.bInterfaceClass = (cl), \
1126 	.bInterfaceSubClass = (sc), \
1127 	.bInterfaceProtocol = (pr)
1128 
1129 /* ----------------------------------------------------------------------- */
1130 
1131 /* Stuff for dynamic usb ids */
1132 struct usb_dynids {
1133 	spinlock_t lock;
1134 	struct list_head list;
1135 };
1136 
1137 struct usb_dynid {
1138 	struct list_head node;
1139 	struct usb_device_id id;
1140 };
1141 
1142 extern ssize_t usb_store_new_id(struct usb_dynids *dynids,
1143 				const struct usb_device_id *id_table,
1144 				struct device_driver *driver,
1145 				const char *buf, size_t count);
1146 
1147 extern ssize_t usb_show_dynids(struct usb_dynids *dynids, char *buf);
1148 
1149 /**
1150  * struct usb_driver - identifies USB interface driver to usbcore
1151  * @name: The driver name should be unique among USB drivers,
1152  *	and should normally be the same as the module name.
1153  * @probe: Called to see if the driver is willing to manage a particular
1154  *	interface on a device.  If it is, probe returns zero and uses
1155  *	usb_set_intfdata() to associate driver-specific data with the
1156  *	interface.  It may also use usb_set_interface() to specify the
1157  *	appropriate altsetting.  If unwilling to manage the interface,
1158  *	return -ENODEV, if genuine IO errors occurred, an appropriate
1159  *	negative errno value.
1160  * @disconnect: Called when the interface is no longer accessible, usually
1161  *	because its device has been (or is being) disconnected or the
1162  *	driver module is being unloaded.
1163  * @unlocked_ioctl: Used for drivers that want to talk to userspace through
1164  *	the "usbfs" filesystem.  This lets devices provide ways to
1165  *	expose information to user space regardless of where they
1166  *	do (or don't) show up otherwise in the filesystem.
1167  * @suspend: Called when the device is going to be suspended by the
1168  *	system either from system sleep or runtime suspend context. The
1169  *	return value will be ignored in system sleep context, so do NOT
1170  *	try to continue using the device if suspend fails in this case.
1171  *	Instead, let the resume or reset-resume routine recover from
1172  *	the failure.
1173  * @resume: Called when the device is being resumed by the system.
1174  * @reset_resume: Called when the suspended device has been reset instead
1175  *	of being resumed.
1176  * @pre_reset: Called by usb_reset_device() when the device is about to be
1177  *	reset.  This routine must not return until the driver has no active
1178  *	URBs for the device, and no more URBs may be submitted until the
1179  *	post_reset method is called.
1180  * @post_reset: Called by usb_reset_device() after the device
1181  *	has been reset
1182  * @shutdown: Called at shut-down time to quiesce the device.
1183  * @id_table: USB drivers use ID table to support hotplugging.
1184  *	Export this with MODULE_DEVICE_TABLE(usb,...).  This must be set
1185  *	or your driver's probe function will never get called.
1186  * @dev_groups: Attributes attached to the device that will be created once it
1187  *	is bound to the driver.
1188  * @dynids: used internally to hold the list of dynamically added device
1189  *	ids for this driver.
1190  * @driver: The driver-model core driver structure.
1191  * @no_dynamic_id: if set to 1, the USB core will not allow dynamic ids to be
1192  *	added to this driver by preventing the sysfs file from being created.
1193  * @supports_autosuspend: if set to 0, the USB core will not allow autosuspend
1194  *	for interfaces bound to this driver.
1195  * @soft_unbind: if set to 1, the USB core will not kill URBs and disable
1196  *	endpoints before calling the driver's disconnect method.
1197  * @disable_hub_initiated_lpm: if set to 1, the USB core will not allow hubs
1198  *	to initiate lower power link state transitions when an idle timeout
1199  *	occurs.  Device-initiated USB 3.0 link PM will still be allowed.
1200  *
1201  * USB interface drivers must provide a name, probe() and disconnect()
1202  * methods, and an id_table.  Other driver fields are optional.
1203  *
1204  * The id_table is used in hotplugging.  It holds a set of descriptors,
1205  * and specialized data may be associated with each entry.  That table
1206  * is used by both user and kernel mode hotplugging support.
1207  *
1208  * The probe() and disconnect() methods are called in a context where
1209  * they can sleep, but they should avoid abusing the privilege.  Most
1210  * work to connect to a device should be done when the device is opened,
1211  * and undone at the last close.  The disconnect code needs to address
1212  * concurrency issues with respect to open() and close() methods, as
1213  * well as forcing all pending I/O requests to complete (by unlinking
1214  * them as necessary, and blocking until the unlinks complete).
1215  */
1216 struct usb_driver {
1217 	const char *name;
1218 
1219 	int (*probe) (struct usb_interface *intf,
1220 		      const struct usb_device_id *id);
1221 
1222 	void (*disconnect) (struct usb_interface *intf);
1223 
1224 	int (*unlocked_ioctl) (struct usb_interface *intf, unsigned int code,
1225 			void *buf);
1226 
1227 	int (*suspend) (struct usb_interface *intf, pm_message_t message);
1228 	int (*resume) (struct usb_interface *intf);
1229 	int (*reset_resume)(struct usb_interface *intf);
1230 
1231 	int (*pre_reset)(struct usb_interface *intf);
1232 	int (*post_reset)(struct usb_interface *intf);
1233 
1234 	void (*shutdown)(struct usb_interface *intf);
1235 
1236 	const struct usb_device_id *id_table;
1237 	const struct attribute_group **dev_groups;
1238 
1239 	struct usb_dynids dynids;
1240 	struct device_driver driver;
1241 	unsigned int no_dynamic_id:1;
1242 	unsigned int supports_autosuspend:1;
1243 	unsigned int disable_hub_initiated_lpm:1;
1244 	unsigned int soft_unbind:1;
1245 };
1246 #define	to_usb_driver(d) container_of(d, struct usb_driver, driver)
1247 
1248 /**
1249  * struct usb_device_driver - identifies USB device driver to usbcore
1250  * @name: The driver name should be unique among USB drivers,
1251  *	and should normally be the same as the module name.
1252  * @match: If set, used for better device/driver matching.
1253  * @probe: Called to see if the driver is willing to manage a particular
1254  *	device.  If it is, probe returns zero and uses dev_set_drvdata()
1255  *	to associate driver-specific data with the device.  If unwilling
1256  *	to manage the device, return a negative errno value.
1257  * @disconnect: Called when the device is no longer accessible, usually
1258  *	because it has been (or is being) disconnected or the driver's
1259  *	module is being unloaded.
1260  * @suspend: Called when the device is going to be suspended by the system.
1261  * @resume: Called when the device is being resumed by the system.
1262  * @choose_configuration: If non-NULL, called instead of the default
1263  *	usb_choose_configuration(). If this returns an error then we'll go
1264  *	on to call the normal usb_choose_configuration().
1265  * @dev_groups: Attributes attached to the device that will be created once it
1266  *	is bound to the driver.
1267  * @driver: The driver-model core driver structure.
1268  * @id_table: used with @match() to select better matching driver at
1269  * 	probe() time.
1270  * @supports_autosuspend: if set to 0, the USB core will not allow autosuspend
1271  *	for devices bound to this driver.
1272  * @generic_subclass: if set to 1, the generic USB driver's probe, disconnect,
1273  *	resume and suspend functions will be called in addition to the driver's
1274  *	own, so this part of the setup does not need to be replicated.
1275  *
1276  * USB drivers must provide all the fields listed above except driver,
1277  * match, and id_table.
1278  */
1279 struct usb_device_driver {
1280 	const char *name;
1281 
1282 	bool (*match) (struct usb_device *udev);
1283 	int (*probe) (struct usb_device *udev);
1284 	void (*disconnect) (struct usb_device *udev);
1285 
1286 	int (*suspend) (struct usb_device *udev, pm_message_t message);
1287 	int (*resume) (struct usb_device *udev, pm_message_t message);
1288 
1289 	int (*choose_configuration) (struct usb_device *udev);
1290 
1291 	const struct attribute_group **dev_groups;
1292 	struct device_driver driver;
1293 	const struct usb_device_id *id_table;
1294 	unsigned int supports_autosuspend:1;
1295 	unsigned int generic_subclass:1;
1296 };
1297 #define	to_usb_device_driver(d) container_of(d, struct usb_device_driver, \
1298 		driver)
1299 
1300 /**
1301  * struct usb_class_driver - identifies a USB driver that wants to use the USB major number
1302  * @name: the usb class device name for this driver.  Will show up in sysfs.
1303  * @devnode: Callback to provide a naming hint for a possible
1304  *	device node to create.
1305  * @fops: pointer to the struct file_operations of this driver.
1306  * @minor_base: the start of the minor range for this driver.
1307  *
1308  * This structure is used for the usb_register_dev() and
1309  * usb_deregister_dev() functions, to consolidate a number of the
1310  * parameters used for them.
1311  */
1312 struct usb_class_driver {
1313 	char *name;
1314 	char *(*devnode)(const struct device *dev, umode_t *mode);
1315 	const struct file_operations *fops;
1316 	int minor_base;
1317 };
1318 
1319 /*
1320  * use these in module_init()/module_exit()
1321  * and don't forget MODULE_DEVICE_TABLE(usb, ...)
1322  */
1323 extern int usb_register_driver(struct usb_driver *, struct module *,
1324 			       const char *);
1325 
1326 /* use a define to avoid include chaining to get THIS_MODULE & friends */
1327 #define usb_register(driver) \
1328 	usb_register_driver(driver, THIS_MODULE, KBUILD_MODNAME)
1329 
1330 extern void usb_deregister(struct usb_driver *);
1331 
1332 /**
1333  * module_usb_driver() - Helper macro for registering a USB driver
1334  * @__usb_driver: usb_driver struct
1335  *
1336  * Helper macro for USB drivers which do not do anything special in module
1337  * init/exit. This eliminates a lot of boilerplate. Each module may only
1338  * use this macro once, and calling it replaces module_init() and module_exit()
1339  */
1340 #define module_usb_driver(__usb_driver) \
1341 	module_driver(__usb_driver, usb_register, \
1342 		       usb_deregister)
1343 
1344 extern int usb_register_device_driver(struct usb_device_driver *,
1345 			struct module *);
1346 extern void usb_deregister_device_driver(struct usb_device_driver *);
1347 
1348 extern int usb_register_dev(struct usb_interface *intf,
1349 			    struct usb_class_driver *class_driver);
1350 extern void usb_deregister_dev(struct usb_interface *intf,
1351 			       struct usb_class_driver *class_driver);
1352 
1353 extern int usb_disabled(void);
1354 
1355 /* ----------------------------------------------------------------------- */
1356 
1357 /*
1358  * URB support, for asynchronous request completions
1359  */
1360 
1361 /*
1362  * urb->transfer_flags:
1363  *
1364  * Note: URB_DIR_IN/OUT is automatically set in usb_submit_urb().
1365  */
1366 #define URB_SHORT_NOT_OK	0x0001	/* report short reads as errors */
1367 #define URB_ISO_ASAP		0x0002	/* iso-only; use the first unexpired
1368 					 * slot in the schedule */
1369 #define URB_NO_TRANSFER_DMA_MAP	0x0004	/* urb->transfer_dma valid on submit */
1370 #define URB_ZERO_PACKET		0x0040	/* Finish bulk OUT with short packet */
1371 #define URB_NO_INTERRUPT	0x0080	/* HINT: no non-error interrupt
1372 					 * needed */
1373 #define URB_FREE_BUFFER		0x0100	/* Free transfer buffer with the URB */
1374 
1375 /* The following flags are used internally by usbcore and HCDs */
1376 #define URB_DIR_IN		0x0200	/* Transfer from device to host */
1377 #define URB_DIR_OUT		0
1378 #define URB_DIR_MASK		URB_DIR_IN
1379 
1380 #define URB_DMA_MAP_SINGLE	0x00010000	/* Non-scatter-gather mapping */
1381 #define URB_DMA_MAP_PAGE	0x00020000	/* HCD-unsupported S-G */
1382 #define URB_DMA_MAP_SG		0x00040000	/* HCD-supported S-G */
1383 #define URB_MAP_LOCAL		0x00080000	/* HCD-local-memory mapping */
1384 #define URB_SETUP_MAP_SINGLE	0x00100000	/* Setup packet DMA mapped */
1385 #define URB_SETUP_MAP_LOCAL	0x00200000	/* HCD-local setup packet */
1386 #define URB_DMA_SG_COMBINED	0x00400000	/* S-G entries were combined */
1387 #define URB_ALIGNED_TEMP_BUFFER	0x00800000	/* Temp buffer was alloc'd */
1388 
1389 struct usb_iso_packet_descriptor {
1390 	unsigned int offset;
1391 	unsigned int length;		/* expected length */
1392 	unsigned int actual_length;
1393 	int status;
1394 };
1395 
1396 struct urb;
1397 
1398 struct usb_anchor {
1399 	struct list_head urb_list;
1400 	wait_queue_head_t wait;
1401 	spinlock_t lock;
1402 	atomic_t suspend_wakeups;
1403 	unsigned int poisoned:1;
1404 };
1405 
init_usb_anchor(struct usb_anchor * anchor)1406 static inline void init_usb_anchor(struct usb_anchor *anchor)
1407 {
1408 	memset(anchor, 0, sizeof(*anchor));
1409 	INIT_LIST_HEAD(&anchor->urb_list);
1410 	init_waitqueue_head(&anchor->wait);
1411 	spin_lock_init(&anchor->lock);
1412 }
1413 
1414 typedef void (*usb_complete_t)(struct urb *);
1415 
1416 /**
1417  * struct urb - USB Request Block
1418  * @urb_list: For use by current owner of the URB.
1419  * @anchor_list: membership in the list of an anchor
1420  * @anchor: to anchor URBs to a common mooring
1421  * @ep: Points to the endpoint's data structure.  Will eventually
1422  *	replace @pipe.
1423  * @pipe: Holds endpoint number, direction, type, and more.
1424  *	Create these values with the eight macros available;
1425  *	usb_{snd,rcv}TYPEpipe(dev,endpoint), where the TYPE is "ctrl"
1426  *	(control), "bulk", "int" (interrupt), or "iso" (isochronous).
1427  *	For example usb_sndbulkpipe() or usb_rcvintpipe().  Endpoint
1428  *	numbers range from zero to fifteen.  Note that "in" endpoint two
1429  *	is a different endpoint (and pipe) from "out" endpoint two.
1430  *	The current configuration controls the existence, type, and
1431  *	maximum packet size of any given endpoint.
1432  * @stream_id: the endpoint's stream ID for bulk streams
1433  * @dev: Identifies the USB device to perform the request.
1434  * @status: This is read in non-iso completion functions to get the
1435  *	status of the particular request.  ISO requests only use it
1436  *	to tell whether the URB was unlinked; detailed status for
1437  *	each frame is in the fields of the iso_frame-desc.
1438  * @transfer_flags: A variety of flags may be used to affect how URB
1439  *	submission, unlinking, or operation are handled.  Different
1440  *	kinds of URB can use different flags.
1441  * @transfer_buffer:  This identifies the buffer to (or from) which the I/O
1442  *	request will be performed unless URB_NO_TRANSFER_DMA_MAP is set
1443  *	(however, do not leave garbage in transfer_buffer even then).
1444  *	This buffer must be suitable for DMA; allocate it with
1445  *	kmalloc() or equivalent.  For transfers to "in" endpoints, contents
1446  *	of this buffer will be modified.  This buffer is used for the data
1447  *	stage of control transfers.
1448  * @transfer_dma: When transfer_flags includes URB_NO_TRANSFER_DMA_MAP,
1449  *	the device driver is saying that it provided this DMA address,
1450  *	which the host controller driver should use in preference to the
1451  *	transfer_buffer.
1452  * @sg: scatter gather buffer list, the buffer size of each element in
1453  * 	the list (except the last) must be divisible by the endpoint's
1454  * 	max packet size if no_sg_constraint isn't set in 'struct usb_bus'
1455  * @num_mapped_sgs: (internal) number of mapped sg entries
1456  * @num_sgs: number of entries in the sg list
1457  * @transfer_buffer_length: How big is transfer_buffer.  The transfer may
1458  *	be broken up into chunks according to the current maximum packet
1459  *	size for the endpoint, which is a function of the configuration
1460  *	and is encoded in the pipe.  When the length is zero, neither
1461  *	transfer_buffer nor transfer_dma is used.
1462  * @actual_length: This is read in non-iso completion functions, and
1463  *	it tells how many bytes (out of transfer_buffer_length) were
1464  *	transferred.  It will normally be the same as requested, unless
1465  *	either an error was reported or a short read was performed.
1466  *	The URB_SHORT_NOT_OK transfer flag may be used to make such
1467  *	short reads be reported as errors.
1468  * @setup_packet: Only used for control transfers, this points to eight bytes
1469  *	of setup data.  Control transfers always start by sending this data
1470  *	to the device.  Then transfer_buffer is read or written, if needed.
1471  * @setup_dma: DMA pointer for the setup packet.  The caller must not use
1472  *	this field; setup_packet must point to a valid buffer.
1473  * @start_frame: Returns the initial frame for isochronous transfers.
1474  * @number_of_packets: Lists the number of ISO transfer buffers.
1475  * @interval: Specifies the polling interval for interrupt or isochronous
1476  *	transfers.  The units are frames (milliseconds) for full and low
1477  *	speed devices, and microframes (1/8 millisecond) for highspeed
1478  *	and SuperSpeed devices.
1479  * @error_count: Returns the number of ISO transfers that reported errors.
1480  * @context: For use in completion functions.  This normally points to
1481  *	request-specific driver context.
1482  * @complete: Completion handler. This URB is passed as the parameter to the
1483  *	completion function.  The completion function may then do what
1484  *	it likes with the URB, including resubmitting or freeing it.
1485  * @iso_frame_desc: Used to provide arrays of ISO transfer buffers and to
1486  *	collect the transfer status for each buffer.
1487  *
1488  * This structure identifies USB transfer requests.  URBs must be allocated by
1489  * calling usb_alloc_urb() and freed with a call to usb_free_urb().
1490  * Initialization may be done using various usb_fill_*_urb() functions.  URBs
1491  * are submitted using usb_submit_urb(), and pending requests may be canceled
1492  * using usb_unlink_urb() or usb_kill_urb().
1493  *
1494  * Data Transfer Buffers:
1495  *
1496  * Normally drivers provide I/O buffers allocated with kmalloc() or otherwise
1497  * taken from the general page pool.  That is provided by transfer_buffer
1498  * (control requests also use setup_packet), and host controller drivers
1499  * perform a dma mapping (and unmapping) for each buffer transferred.  Those
1500  * mapping operations can be expensive on some platforms (perhaps using a dma
1501  * bounce buffer or talking to an IOMMU),
1502  * although they're cheap on commodity x86 and ppc hardware.
1503  *
1504  * Alternatively, drivers may pass the URB_NO_TRANSFER_DMA_MAP transfer flag,
1505  * which tells the host controller driver that no such mapping is needed for
1506  * the transfer_buffer since
1507  * the device driver is DMA-aware.  For example, a device driver might
1508  * allocate a DMA buffer with usb_alloc_coherent() or call usb_buffer_map().
1509  * When this transfer flag is provided, host controller drivers will
1510  * attempt to use the dma address found in the transfer_dma
1511  * field rather than determining a dma address themselves.
1512  *
1513  * Note that transfer_buffer must still be set if the controller
1514  * does not support DMA (as indicated by hcd_uses_dma()) and when talking
1515  * to root hub. If you have to transfer between highmem zone and the device
1516  * on such controller, create a bounce buffer or bail out with an error.
1517  * If transfer_buffer cannot be set (is in highmem) and the controller is DMA
1518  * capable, assign NULL to it, so that usbmon knows not to use the value.
1519  * The setup_packet must always be set, so it cannot be located in highmem.
1520  *
1521  * Initialization:
1522  *
1523  * All URBs submitted must initialize the dev, pipe, transfer_flags (may be
1524  * zero), and complete fields.  All URBs must also initialize
1525  * transfer_buffer and transfer_buffer_length.  They may provide the
1526  * URB_SHORT_NOT_OK transfer flag, indicating that short reads are
1527  * to be treated as errors; that flag is invalid for write requests.
1528  *
1529  * Bulk URBs may
1530  * use the URB_ZERO_PACKET transfer flag, indicating that bulk OUT transfers
1531  * should always terminate with a short packet, even if it means adding an
1532  * extra zero length packet.
1533  *
1534  * Control URBs must provide a valid pointer in the setup_packet field.
1535  * Unlike the transfer_buffer, the setup_packet may not be mapped for DMA
1536  * beforehand.
1537  *
1538  * Interrupt URBs must provide an interval, saying how often (in milliseconds
1539  * or, for highspeed devices, 125 microsecond units)
1540  * to poll for transfers.  After the URB has been submitted, the interval
1541  * field reflects how the transfer was actually scheduled.
1542  * The polling interval may be more frequent than requested.
1543  * For example, some controllers have a maximum interval of 32 milliseconds,
1544  * while others support intervals of up to 1024 milliseconds.
1545  * Isochronous URBs also have transfer intervals.  (Note that for isochronous
1546  * endpoints, as well as high speed interrupt endpoints, the encoding of
1547  * the transfer interval in the endpoint descriptor is logarithmic.
1548  * Device drivers must convert that value to linear units themselves.)
1549  *
1550  * If an isochronous endpoint queue isn't already running, the host
1551  * controller will schedule a new URB to start as soon as bandwidth
1552  * utilization allows.  If the queue is running then a new URB will be
1553  * scheduled to start in the first transfer slot following the end of the
1554  * preceding URB, if that slot has not already expired.  If the slot has
1555  * expired (which can happen when IRQ delivery is delayed for a long time),
1556  * the scheduling behavior depends on the URB_ISO_ASAP flag.  If the flag
1557  * is clear then the URB will be scheduled to start in the expired slot,
1558  * implying that some of its packets will not be transferred; if the flag
1559  * is set then the URB will be scheduled in the first unexpired slot,
1560  * breaking the queue's synchronization.  Upon URB completion, the
1561  * start_frame field will be set to the (micro)frame number in which the
1562  * transfer was scheduled.  Ranges for frame counter values are HC-specific
1563  * and can go from as low as 256 to as high as 65536 frames.
1564  *
1565  * Isochronous URBs have a different data transfer model, in part because
1566  * the quality of service is only "best effort".  Callers provide specially
1567  * allocated URBs, with number_of_packets worth of iso_frame_desc structures
1568  * at the end.  Each such packet is an individual ISO transfer.  Isochronous
1569  * URBs are normally queued, submitted by drivers to arrange that
1570  * transfers are at least double buffered, and then explicitly resubmitted
1571  * in completion handlers, so
1572  * that data (such as audio or video) streams at as constant a rate as the
1573  * host controller scheduler can support.
1574  *
1575  * Completion Callbacks:
1576  *
1577  * The completion callback is made in_interrupt(), and one of the first
1578  * things that a completion handler should do is check the status field.
1579  * The status field is provided for all URBs.  It is used to report
1580  * unlinked URBs, and status for all non-ISO transfers.  It should not
1581  * be examined before the URB is returned to the completion handler.
1582  *
1583  * The context field is normally used to link URBs back to the relevant
1584  * driver or request state.
1585  *
1586  * When the completion callback is invoked for non-isochronous URBs, the
1587  * actual_length field tells how many bytes were transferred.  This field
1588  * is updated even when the URB terminated with an error or was unlinked.
1589  *
1590  * ISO transfer status is reported in the status and actual_length fields
1591  * of the iso_frame_desc array, and the number of errors is reported in
1592  * error_count.  Completion callbacks for ISO transfers will normally
1593  * (re)submit URBs to ensure a constant transfer rate.
1594  *
1595  * Note that even fields marked "public" should not be touched by the driver
1596  * when the urb is owned by the hcd, that is, since the call to
1597  * usb_submit_urb() till the entry into the completion routine.
1598  */
1599 struct urb {
1600 	/* private: usb core and host controller only fields in the urb */
1601 	struct kref kref;		/* reference count of the URB */
1602 	int unlinked;			/* unlink error code */
1603 	void *hcpriv;			/* private data for host controller */
1604 	atomic_t use_count;		/* concurrent submissions counter */
1605 	atomic_t reject;		/* submissions will fail */
1606 
1607 	/* public: documented fields in the urb that can be used by drivers */
1608 	struct list_head urb_list;	/* list head for use by the urb's
1609 					 * current owner */
1610 	struct list_head anchor_list;	/* the URB may be anchored */
1611 	struct usb_anchor *anchor;
1612 	struct usb_device *dev;		/* (in) pointer to associated device */
1613 	struct usb_host_endpoint *ep;	/* (internal) pointer to endpoint */
1614 	unsigned int pipe;		/* (in) pipe information */
1615 	unsigned int stream_id;		/* (in) stream ID */
1616 	int status;			/* (return) non-ISO status */
1617 	unsigned int transfer_flags;	/* (in) URB_SHORT_NOT_OK | ...*/
1618 	void *transfer_buffer;		/* (in) associated data buffer */
1619 	dma_addr_t transfer_dma;	/* (in) dma addr for transfer_buffer */
1620 	struct scatterlist *sg;		/* (in) scatter gather buffer list */
1621 	int num_mapped_sgs;		/* (internal) mapped sg entries */
1622 	int num_sgs;			/* (in) number of entries in the sg list */
1623 	u32 transfer_buffer_length;	/* (in) data buffer length */
1624 	u32 actual_length;		/* (return) actual transfer length */
1625 	unsigned char *setup_packet;	/* (in) setup packet (control only) */
1626 	dma_addr_t setup_dma;		/* (in) dma addr for setup_packet */
1627 	int start_frame;		/* (modify) start frame (ISO) */
1628 	int number_of_packets;		/* (in) number of ISO packets */
1629 	int interval;			/* (modify) transfer interval
1630 					 * (INT/ISO) */
1631 	int error_count;		/* (return) number of ISO errors */
1632 	void *context;			/* (in) context for completion */
1633 	usb_complete_t complete;	/* (in) completion routine */
1634 	struct usb_iso_packet_descriptor iso_frame_desc[];
1635 					/* (in) ISO ONLY */
1636 };
1637 
1638 /* ----------------------------------------------------------------------- */
1639 
1640 /**
1641  * usb_fill_control_urb - initializes a control urb
1642  * @urb: pointer to the urb to initialize.
1643  * @dev: pointer to the struct usb_device for this urb.
1644  * @pipe: the endpoint pipe
1645  * @setup_packet: pointer to the setup_packet buffer. The buffer must be
1646  *	suitable for DMA.
1647  * @transfer_buffer: pointer to the transfer buffer. The buffer must be
1648  *	suitable for DMA.
1649  * @buffer_length: length of the transfer buffer
1650  * @complete_fn: pointer to the usb_complete_t function
1651  * @context: what to set the urb context to.
1652  *
1653  * Initializes a control urb with the proper information needed to submit
1654  * it to a device.
1655  *
1656  * The transfer buffer and the setup_packet buffer will most likely be filled
1657  * or read via DMA. The simplest way to get a buffer that can be DMAed to is
1658  * allocating it via kmalloc() or equivalent, even for very small buffers.
1659  * If the buffers are embedded in a bigger structure, there is a risk that
1660  * the buffer itself, the previous fields and/or the next fields are corrupted
1661  * due to cache incoherencies; or slowed down if they are evicted from the
1662  * cache. For more information, check &struct urb.
1663  *
1664  */
usb_fill_control_urb(struct urb * urb,struct usb_device * dev,unsigned int pipe,unsigned char * setup_packet,void * transfer_buffer,int buffer_length,usb_complete_t complete_fn,void * context)1665 static inline void usb_fill_control_urb(struct urb *urb,
1666 					struct usb_device *dev,
1667 					unsigned int pipe,
1668 					unsigned char *setup_packet,
1669 					void *transfer_buffer,
1670 					int buffer_length,
1671 					usb_complete_t complete_fn,
1672 					void *context)
1673 {
1674 	urb->dev = dev;
1675 	urb->pipe = pipe;
1676 	urb->setup_packet = setup_packet;
1677 	urb->transfer_buffer = transfer_buffer;
1678 	urb->transfer_buffer_length = buffer_length;
1679 	urb->complete = complete_fn;
1680 	urb->context = context;
1681 }
1682 
1683 /**
1684  * usb_fill_bulk_urb - macro to help initialize a bulk urb
1685  * @urb: pointer to the urb to initialize.
1686  * @dev: pointer to the struct usb_device for this urb.
1687  * @pipe: the endpoint pipe
1688  * @transfer_buffer: pointer to the transfer buffer. The buffer must be
1689  *	suitable for DMA.
1690  * @buffer_length: length of the transfer buffer
1691  * @complete_fn: pointer to the usb_complete_t function
1692  * @context: what to set the urb context to.
1693  *
1694  * Initializes a bulk urb with the proper information needed to submit it
1695  * to a device.
1696  *
1697  * Refer to usb_fill_control_urb() for a description of the requirements for
1698  * transfer_buffer.
1699  */
usb_fill_bulk_urb(struct urb * urb,struct usb_device * dev,unsigned int pipe,void * transfer_buffer,int buffer_length,usb_complete_t complete_fn,void * context)1700 static inline void usb_fill_bulk_urb(struct urb *urb,
1701 				     struct usb_device *dev,
1702 				     unsigned int pipe,
1703 				     void *transfer_buffer,
1704 				     int buffer_length,
1705 				     usb_complete_t complete_fn,
1706 				     void *context)
1707 {
1708 	urb->dev = dev;
1709 	urb->pipe = pipe;
1710 	urb->transfer_buffer = transfer_buffer;
1711 	urb->transfer_buffer_length = buffer_length;
1712 	urb->complete = complete_fn;
1713 	urb->context = context;
1714 }
1715 
1716 /**
1717  * usb_fill_int_urb - macro to help initialize a interrupt urb
1718  * @urb: pointer to the urb to initialize.
1719  * @dev: pointer to the struct usb_device for this urb.
1720  * @pipe: the endpoint pipe
1721  * @transfer_buffer: pointer to the transfer buffer. The buffer must be
1722  *	suitable for DMA.
1723  * @buffer_length: length of the transfer buffer
1724  * @complete_fn: pointer to the usb_complete_t function
1725  * @context: what to set the urb context to.
1726  * @interval: what to set the urb interval to, encoded like
1727  *	the endpoint descriptor's bInterval value.
1728  *
1729  * Initializes a interrupt urb with the proper information needed to submit
1730  * it to a device.
1731  *
1732  * Refer to usb_fill_control_urb() for a description of the requirements for
1733  * transfer_buffer.
1734  *
1735  * Note that High Speed and SuperSpeed(+) interrupt endpoints use a logarithmic
1736  * encoding of the endpoint interval, and express polling intervals in
1737  * microframes (eight per millisecond) rather than in frames (one per
1738  * millisecond).
1739  */
usb_fill_int_urb(struct urb * urb,struct usb_device * dev,unsigned int pipe,void * transfer_buffer,int buffer_length,usb_complete_t complete_fn,void * context,int interval)1740 static inline void usb_fill_int_urb(struct urb *urb,
1741 				    struct usb_device *dev,
1742 				    unsigned int pipe,
1743 				    void *transfer_buffer,
1744 				    int buffer_length,
1745 				    usb_complete_t complete_fn,
1746 				    void *context,
1747 				    int interval)
1748 {
1749 	urb->dev = dev;
1750 	urb->pipe = pipe;
1751 	urb->transfer_buffer = transfer_buffer;
1752 	urb->transfer_buffer_length = buffer_length;
1753 	urb->complete = complete_fn;
1754 	urb->context = context;
1755 
1756 	if (dev->speed == USB_SPEED_HIGH || dev->speed >= USB_SPEED_SUPER) {
1757 		/* make sure interval is within allowed range */
1758 		interval = clamp(interval, 1, 16);
1759 
1760 		urb->interval = 1 << (interval - 1);
1761 	} else {
1762 		urb->interval = interval;
1763 	}
1764 
1765 	urb->start_frame = -1;
1766 }
1767 
1768 extern void usb_init_urb(struct urb *urb);
1769 extern struct urb *usb_alloc_urb(int iso_packets, gfp_t mem_flags);
1770 extern void usb_free_urb(struct urb *urb);
1771 #define usb_put_urb usb_free_urb
1772 extern struct urb *usb_get_urb(struct urb *urb);
1773 extern int usb_submit_urb(struct urb *urb, gfp_t mem_flags);
1774 extern int usb_unlink_urb(struct urb *urb);
1775 extern void usb_kill_urb(struct urb *urb);
1776 extern void usb_poison_urb(struct urb *urb);
1777 extern void usb_unpoison_urb(struct urb *urb);
1778 extern void usb_block_urb(struct urb *urb);
1779 extern void usb_kill_anchored_urbs(struct usb_anchor *anchor);
1780 extern void usb_poison_anchored_urbs(struct usb_anchor *anchor);
1781 extern void usb_unpoison_anchored_urbs(struct usb_anchor *anchor);
1782 extern void usb_unlink_anchored_urbs(struct usb_anchor *anchor);
1783 extern void usb_anchor_suspend_wakeups(struct usb_anchor *anchor);
1784 extern void usb_anchor_resume_wakeups(struct usb_anchor *anchor);
1785 extern void usb_anchor_urb(struct urb *urb, struct usb_anchor *anchor);
1786 extern void usb_unanchor_urb(struct urb *urb);
1787 extern int usb_wait_anchor_empty_timeout(struct usb_anchor *anchor,
1788 					 unsigned int timeout);
1789 extern struct urb *usb_get_from_anchor(struct usb_anchor *anchor);
1790 extern void usb_scuttle_anchored_urbs(struct usb_anchor *anchor);
1791 extern int usb_anchor_empty(struct usb_anchor *anchor);
1792 
1793 #define usb_unblock_urb	usb_unpoison_urb
1794 
1795 /**
1796  * usb_urb_dir_in - check if an URB describes an IN transfer
1797  * @urb: URB to be checked
1798  *
1799  * Return: 1 if @urb describes an IN transfer (device-to-host),
1800  * otherwise 0.
1801  */
usb_urb_dir_in(struct urb * urb)1802 static inline int usb_urb_dir_in(struct urb *urb)
1803 {
1804 	return (urb->transfer_flags & URB_DIR_MASK) == URB_DIR_IN;
1805 }
1806 
1807 /**
1808  * usb_urb_dir_out - check if an URB describes an OUT transfer
1809  * @urb: URB to be checked
1810  *
1811  * Return: 1 if @urb describes an OUT transfer (host-to-device),
1812  * otherwise 0.
1813  */
usb_urb_dir_out(struct urb * urb)1814 static inline int usb_urb_dir_out(struct urb *urb)
1815 {
1816 	return (urb->transfer_flags & URB_DIR_MASK) == URB_DIR_OUT;
1817 }
1818 
1819 int usb_pipe_type_check(struct usb_device *dev, unsigned int pipe);
1820 int usb_urb_ep_type_check(const struct urb *urb);
1821 
1822 void *usb_alloc_coherent(struct usb_device *dev, size_t size,
1823 	gfp_t mem_flags, dma_addr_t *dma);
1824 void usb_free_coherent(struct usb_device *dev, size_t size,
1825 	void *addr, dma_addr_t dma);
1826 
1827 /*-------------------------------------------------------------------*
1828  *                         SYNCHRONOUS CALL SUPPORT                  *
1829  *-------------------------------------------------------------------*/
1830 
1831 extern int usb_control_msg(struct usb_device *dev, unsigned int pipe,
1832 	__u8 request, __u8 requesttype, __u16 value, __u16 index,
1833 	void *data, __u16 size, int timeout);
1834 extern int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,
1835 	void *data, int len, int *actual_length, int timeout);
1836 extern int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,
1837 	void *data, int len, int *actual_length,
1838 	int timeout);
1839 
1840 /* wrappers around usb_control_msg() for the most common standard requests */
1841 int usb_control_msg_send(struct usb_device *dev, __u8 endpoint, __u8 request,
1842 			 __u8 requesttype, __u16 value, __u16 index,
1843 			 const void *data, __u16 size, int timeout,
1844 			 gfp_t memflags);
1845 int usb_control_msg_recv(struct usb_device *dev, __u8 endpoint, __u8 request,
1846 			 __u8 requesttype, __u16 value, __u16 index,
1847 			 void *data, __u16 size, int timeout,
1848 			 gfp_t memflags);
1849 extern int usb_get_descriptor(struct usb_device *dev, unsigned char desctype,
1850 	unsigned char descindex, void *buf, int size);
1851 extern int usb_get_status(struct usb_device *dev,
1852 	int recip, int type, int target, void *data);
1853 
usb_get_std_status(struct usb_device * dev,int recip,int target,void * data)1854 static inline int usb_get_std_status(struct usb_device *dev,
1855 	int recip, int target, void *data)
1856 {
1857 	return usb_get_status(dev, recip, USB_STATUS_TYPE_STANDARD, target,
1858 		data);
1859 }
1860 
usb_get_ptm_status(struct usb_device * dev,void * data)1861 static inline int usb_get_ptm_status(struct usb_device *dev, void *data)
1862 {
1863 	return usb_get_status(dev, USB_RECIP_DEVICE, USB_STATUS_TYPE_PTM,
1864 		0, data);
1865 }
1866 
1867 extern int usb_string(struct usb_device *dev, int index,
1868 	char *buf, size_t size);
1869 extern char *usb_cache_string(struct usb_device *udev, int index);
1870 
1871 /* wrappers that also update important state inside usbcore */
1872 extern int usb_clear_halt(struct usb_device *dev, int pipe);
1873 extern int usb_reset_configuration(struct usb_device *dev);
1874 extern int usb_set_interface(struct usb_device *dev, int ifnum, int alternate);
1875 extern void usb_reset_endpoint(struct usb_device *dev, unsigned int epaddr);
1876 
1877 /* this request isn't really synchronous, but it belongs with the others */
1878 extern int usb_driver_set_configuration(struct usb_device *udev, int config);
1879 
1880 /* choose and set configuration for device */
1881 extern int usb_choose_configuration(struct usb_device *udev);
1882 extern int usb_set_configuration(struct usb_device *dev, int configuration);
1883 
1884 /*
1885  * timeouts, in milliseconds, used for sending/receiving control messages
1886  * they typically complete within a few frames (msec) after they're issued
1887  * USB identifies 5 second timeouts, maybe more in a few cases, and a few
1888  * slow devices (like some MGE Ellipse UPSes) actually push that limit.
1889  */
1890 #define USB_CTRL_GET_TIMEOUT	5000
1891 #define USB_CTRL_SET_TIMEOUT	5000
1892 
1893 
1894 /**
1895  * struct usb_sg_request - support for scatter/gather I/O
1896  * @status: zero indicates success, else negative errno
1897  * @bytes: counts bytes transferred.
1898  *
1899  * These requests are initialized using usb_sg_init(), and then are used
1900  * as request handles passed to usb_sg_wait() or usb_sg_cancel().  Most
1901  * members of the request object aren't for driver access.
1902  *
1903  * The status and bytecount values are valid only after usb_sg_wait()
1904  * returns.  If the status is zero, then the bytecount matches the total
1905  * from the request.
1906  *
1907  * After an error completion, drivers may need to clear a halt condition
1908  * on the endpoint.
1909  */
1910 struct usb_sg_request {
1911 	int			status;
1912 	size_t			bytes;
1913 
1914 	/* private:
1915 	 * members below are private to usbcore,
1916 	 * and are not provided for driver access!
1917 	 */
1918 	spinlock_t		lock;
1919 
1920 	struct usb_device	*dev;
1921 	int			pipe;
1922 
1923 	int			entries;
1924 	struct urb		**urbs;
1925 
1926 	int			count;
1927 	struct completion	complete;
1928 };
1929 
1930 int usb_sg_init(
1931 	struct usb_sg_request	*io,
1932 	struct usb_device	*dev,
1933 	unsigned		pipe,
1934 	unsigned		period,
1935 	struct scatterlist	*sg,
1936 	int			nents,
1937 	size_t			length,
1938 	gfp_t			mem_flags
1939 );
1940 void usb_sg_cancel(struct usb_sg_request *io);
1941 void usb_sg_wait(struct usb_sg_request *io);
1942 
1943 
1944 /* ----------------------------------------------------------------------- */
1945 
1946 /*
1947  * For various legacy reasons, Linux has a small cookie that's paired with
1948  * a struct usb_device to identify an endpoint queue.  Queue characteristics
1949  * are defined by the endpoint's descriptor.  This cookie is called a "pipe",
1950  * an unsigned int encoded as:
1951  *
1952  *  - direction:	bit 7		(0 = Host-to-Device [Out],
1953  *					 1 = Device-to-Host [In] ...
1954  *					like endpoint bEndpointAddress)
1955  *  - device address:	bits 8-14       ... bit positions known to uhci-hcd
1956  *  - endpoint:		bits 15-18      ... bit positions known to uhci-hcd
1957  *  - pipe type:	bits 30-31	(00 = isochronous, 01 = interrupt,
1958  *					 10 = control, 11 = bulk)
1959  *
1960  * Given the device address and endpoint descriptor, pipes are redundant.
1961  */
1962 
1963 /* NOTE:  these are not the standard USB_ENDPOINT_XFER_* values!! */
1964 /* (yet ... they're the values used by usbfs) */
1965 #define PIPE_ISOCHRONOUS		0
1966 #define PIPE_INTERRUPT			1
1967 #define PIPE_CONTROL			2
1968 #define PIPE_BULK			3
1969 
1970 #define usb_pipein(pipe)	((pipe) & USB_DIR_IN)
1971 #define usb_pipeout(pipe)	(!usb_pipein(pipe))
1972 
1973 #define usb_pipedevice(pipe)	(((pipe) >> 8) & 0x7f)
1974 #define usb_pipeendpoint(pipe)	(((pipe) >> 15) & 0xf)
1975 
1976 #define usb_pipetype(pipe)	(((pipe) >> 30) & 3)
1977 #define usb_pipeisoc(pipe)	(usb_pipetype((pipe)) == PIPE_ISOCHRONOUS)
1978 #define usb_pipeint(pipe)	(usb_pipetype((pipe)) == PIPE_INTERRUPT)
1979 #define usb_pipecontrol(pipe)	(usb_pipetype((pipe)) == PIPE_CONTROL)
1980 #define usb_pipebulk(pipe)	(usb_pipetype((pipe)) == PIPE_BULK)
1981 
__create_pipe(struct usb_device * dev,unsigned int endpoint)1982 static inline unsigned int __create_pipe(struct usb_device *dev,
1983 		unsigned int endpoint)
1984 {
1985 	return (dev->devnum << 8) | (endpoint << 15);
1986 }
1987 
1988 /* Create various pipes... */
1989 #define usb_sndctrlpipe(dev, endpoint)	\
1990 	((PIPE_CONTROL << 30) | __create_pipe(dev, endpoint))
1991 #define usb_rcvctrlpipe(dev, endpoint)	\
1992 	((PIPE_CONTROL << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
1993 #define usb_sndisocpipe(dev, endpoint)	\
1994 	((PIPE_ISOCHRONOUS << 30) | __create_pipe(dev, endpoint))
1995 #define usb_rcvisocpipe(dev, endpoint)	\
1996 	((PIPE_ISOCHRONOUS << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
1997 #define usb_sndbulkpipe(dev, endpoint)	\
1998 	((PIPE_BULK << 30) | __create_pipe(dev, endpoint))
1999 #define usb_rcvbulkpipe(dev, endpoint)	\
2000 	((PIPE_BULK << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
2001 #define usb_sndintpipe(dev, endpoint)	\
2002 	((PIPE_INTERRUPT << 30) | __create_pipe(dev, endpoint))
2003 #define usb_rcvintpipe(dev, endpoint)	\
2004 	((PIPE_INTERRUPT << 30) | __create_pipe(dev, endpoint) | USB_DIR_IN)
2005 
2006 static inline struct usb_host_endpoint *
usb_pipe_endpoint(struct usb_device * dev,unsigned int pipe)2007 usb_pipe_endpoint(struct usb_device *dev, unsigned int pipe)
2008 {
2009 	struct usb_host_endpoint **eps;
2010 	eps = usb_pipein(pipe) ? dev->ep_in : dev->ep_out;
2011 	return eps[usb_pipeendpoint(pipe)];
2012 }
2013 
usb_maxpacket(struct usb_device * udev,int pipe)2014 static inline u16 usb_maxpacket(struct usb_device *udev, int pipe)
2015 {
2016 	struct usb_host_endpoint *ep = usb_pipe_endpoint(udev, pipe);
2017 
2018 	if (!ep)
2019 		return 0;
2020 
2021 	/* NOTE:  only 0x07ff bits are for packet size... */
2022 	return usb_endpoint_maxp(&ep->desc);
2023 }
2024 
2025 /* translate USB error codes to codes user space understands */
usb_translate_errors(int error_code)2026 static inline int usb_translate_errors(int error_code)
2027 {
2028 	switch (error_code) {
2029 	case 0:
2030 	case -ENOMEM:
2031 	case -ENODEV:
2032 	case -EOPNOTSUPP:
2033 		return error_code;
2034 	default:
2035 		return -EIO;
2036 	}
2037 }
2038 
2039 /* Events from the usb core */
2040 #define USB_DEVICE_ADD		0x0001
2041 #define USB_DEVICE_REMOVE	0x0002
2042 #define USB_BUS_ADD		0x0003
2043 #define USB_BUS_REMOVE		0x0004
2044 extern void usb_register_notify(struct notifier_block *nb);
2045 extern void usb_unregister_notify(struct notifier_block *nb);
2046 
2047 /* debugfs stuff */
2048 extern struct dentry *usb_debug_root;
2049 
2050 /* LED triggers */
2051 enum usb_led_event {
2052 	USB_LED_EVENT_HOST = 0,
2053 	USB_LED_EVENT_GADGET = 1,
2054 };
2055 
2056 #ifdef CONFIG_USB_LED_TRIG
2057 extern void usb_led_activity(enum usb_led_event ev);
2058 #else
usb_led_activity(enum usb_led_event ev)2059 static inline void usb_led_activity(enum usb_led_event ev) {}
2060 #endif
2061 
2062 #endif  /* __KERNEL__ */
2063 
2064 #endif
2065