1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * composite.h -- framework for usb gadgets which are composite devices
4  *
5  * Copyright (C) 2006-2008 David Brownell
6  */
7 
8 #ifndef	__LINUX_USB_COMPOSITE_H
9 #define	__LINUX_USB_COMPOSITE_H
10 
11 /*
12  * This framework is an optional layer on top of the USB Gadget interface,
13  * making it easier to build (a) Composite devices, supporting multiple
14  * functions within any single configuration, and (b) Multi-configuration
15  * devices, also supporting multiple functions but without necessarily
16  * having more than one function per configuration.
17  *
18  * Example:  a device with a single configuration supporting both network
19  * link and mass storage functions is a composite device.  Those functions
20  * might alternatively be packaged in individual configurations, but in
21  * the composite model the host can use both functions at the same time.
22  */
23 
24 #include <linux/bcd.h>
25 #include <linux/version.h>
26 #include <linux/usb/ch9.h>
27 #include <linux/usb/gadget.h>
28 #include <linux/usb/webusb.h>
29 #include <linux/log2.h>
30 #include <linux/configfs.h>
31 
32 /*
33  * USB function drivers should return USB_GADGET_DELAYED_STATUS if they
34  * wish to delay the data/status stages of the control transfer till they
35  * are ready. The control transfer will then be kept from completing till
36  * all the function drivers that requested for USB_GADGET_DELAYED_STAUS
37  * invoke usb_composite_setup_continue().
38  */
39 #define USB_GADGET_DELAYED_STATUS       0x7fff	/* Impossibly large value */
40 
41 /* big enough to hold our biggest descriptor */
42 #define USB_COMP_EP0_BUFSIZ	4096
43 
44 /* OS feature descriptor length <= 4kB */
45 #define USB_COMP_EP0_OS_DESC_BUFSIZ	4096
46 
47 #define USB_MS_TO_HS_INTERVAL(x)	(ilog2((x * 1000 / 125)) + 1)
48 struct usb_configuration;
49 
50 /**
51  * struct usb_os_desc_ext_prop - describes one "Extended Property"
52  * @entry: used to keep a list of extended properties
53  * @type: Extended Property type
54  * @name_len: Extended Property unicode name length, including terminating '\0'
55  * @name: Extended Property name
56  * @data_len: Length of Extended Property blob (for unicode store double len)
57  * @data: Extended Property blob
58  * @item: Represents this Extended Property in configfs
59  */
60 struct usb_os_desc_ext_prop {
61 	struct list_head	entry;
62 	u8			type;
63 	int			name_len;
64 	char			*name;
65 	int			data_len;
66 	char			*data;
67 	struct config_item	item;
68 };
69 
70 /**
71  * struct usb_os_desc - describes OS descriptors associated with one interface
72  * @ext_compat_id: 16 bytes of "Compatible ID" and "Subcompatible ID"
73  * @ext_prop: Extended Properties list
74  * @ext_prop_len: Total length of Extended Properties blobs
75  * @ext_prop_count: Number of Extended Properties
76  * @opts_mutex: Optional mutex protecting config data of a usb_function_instance
77  * @group: Represents OS descriptors associated with an interface in configfs
78  * @owner: Module associated with this OS descriptor
79  */
80 struct usb_os_desc {
81 	char			*ext_compat_id;
82 	struct list_head	ext_prop;
83 	int			ext_prop_len;
84 	int			ext_prop_count;
85 	struct mutex		*opts_mutex;
86 	struct config_group	group;
87 	struct module		*owner;
88 };
89 
90 /**
91  * struct usb_os_desc_table - describes OS descriptors associated with one
92  * interface of a usb_function
93  * @if_id: Interface id
94  * @os_desc: "Extended Compatibility ID" and "Extended Properties" of the
95  *	interface
96  *
97  * Each interface can have at most one "Extended Compatibility ID" and a
98  * number of "Extended Properties".
99  */
100 struct usb_os_desc_table {
101 	int			if_id;
102 	struct usb_os_desc	*os_desc;
103 };
104 
105 /**
106  * struct usb_function - describes one function of a configuration
107  * @name: For diagnostics, identifies the function.
108  * @strings: tables of strings, keyed by identifiers assigned during bind()
109  *	and by language IDs provided in control requests
110  * @fs_descriptors: Table of full (or low) speed descriptors, using interface and
111  *	string identifiers assigned during @bind().  If this pointer is null,
112  *	the function will not be available at full speed (or at low speed).
113  * @hs_descriptors: Table of high speed descriptors, using interface and
114  *	string identifiers assigned during @bind().  If this pointer is null,
115  *	the function will not be available at high speed.
116  * @ss_descriptors: Table of super speed descriptors, using interface and
117  *	string identifiers assigned during @bind(). If this
118  *	pointer is null after initiation, the function will not
119  *	be available at super speed.
120  * @ssp_descriptors: Table of super speed plus descriptors, using
121  *	interface and string identifiers assigned during @bind(). If
122  *	this pointer is null after initiation, the function will not
123  *	be available at super speed plus.
124  * @config: assigned when @usb_add_function() is called; this is the
125  *	configuration with which this function is associated.
126  * @os_desc_table: Table of (interface id, os descriptors) pairs. The function
127  *	can expose more than one interface. If an interface is a member of
128  *	an IAD, only the first interface of IAD has its entry in the table.
129  * @os_desc_n: Number of entries in os_desc_table
130  * @bind: Before the gadget can register, all of its functions bind() to the
131  *	available resources including string and interface identifiers used
132  *	in interface or class descriptors; endpoints; I/O buffers; and so on.
133  * @unbind: Reverses @bind; called as a side effect of unregistering the
134  *	driver which added this function.
135  * @free_func: free the struct usb_function.
136  * @mod: (internal) points to the module that created this structure.
137  * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may
138  *	initialize usb_ep.driver data at this time (when it is used).
139  *	Note that setting an interface to its current altsetting resets
140  *	interface state, and that all interfaces have a disabled state.
141  * @get_alt: Returns the active altsetting.  If this is not provided,
142  *	then only altsetting zero is supported.
143  * @disable: (REQUIRED) Indicates the function should be disabled.  Reasons
144  *	include host resetting or reconfiguring the gadget, and disconnection.
145  * @setup: Used for interface-specific control requests.
146  * @req_match: Tests if a given class request can be handled by this function.
147  * @suspend: Notifies functions when the host stops sending USB traffic.
148  * @resume: Notifies functions when the host restarts USB traffic.
149  * @get_status: Returns function status as a reply to
150  *	GetStatus() request when the recipient is Interface.
151  * @func_suspend: callback to be called when
152  *	SetFeature(FUNCTION_SUSPEND) is reseived
153  *
154  * A single USB function uses one or more interfaces, and should in most
155  * cases support operation at both full and high speeds.  Each function is
156  * associated by @usb_add_function() with a one configuration; that function
157  * causes @bind() to be called so resources can be allocated as part of
158  * setting up a gadget driver.  Those resources include endpoints, which
159  * should be allocated using @usb_ep_autoconfig().
160  *
161  * To support dual speed operation, a function driver provides descriptors
162  * for both high and full speed operation.  Except in rare cases that don't
163  * involve bulk endpoints, each speed needs different endpoint descriptors.
164  *
165  * Function drivers choose their own strategies for managing instance data.
166  * The simplest strategy just declares it "static', which means the function
167  * can only be activated once.  If the function needs to be exposed in more
168  * than one configuration at a given speed, it needs to support multiple
169  * usb_function structures (one for each configuration).
170  *
171  * A more complex strategy might encapsulate a @usb_function structure inside
172  * a driver-specific instance structure to allows multiple activations.  An
173  * example of multiple activations might be a CDC ACM function that supports
174  * two or more distinct instances within the same configuration, providing
175  * several independent logical data links to a USB host.
176  */
177 
178 struct usb_function {
179 	const char			*name;
180 	struct usb_gadget_strings	**strings;
181 	struct usb_descriptor_header	**fs_descriptors;
182 	struct usb_descriptor_header	**hs_descriptors;
183 	struct usb_descriptor_header	**ss_descriptors;
184 	struct usb_descriptor_header	**ssp_descriptors;
185 
186 	struct usb_configuration	*config;
187 
188 	struct usb_os_desc_table	*os_desc_table;
189 	unsigned			os_desc_n;
190 
191 	/* REVISIT:  bind() functions can be marked __init, which
192 	 * makes trouble for section mismatch analysis.  See if
193 	 * we can't restructure things to avoid mismatching.
194 	 * Related:  unbind() may kfree() but bind() won't...
195 	 */
196 
197 	/* configuration management:  bind/unbind */
198 	int			(*bind)(struct usb_configuration *,
199 					struct usb_function *);
200 	void			(*unbind)(struct usb_configuration *,
201 					struct usb_function *);
202 	void			(*free_func)(struct usb_function *f);
203 	struct module		*mod;
204 
205 	/* runtime state management */
206 	int			(*set_alt)(struct usb_function *,
207 					unsigned interface, unsigned alt);
208 	int			(*get_alt)(struct usb_function *,
209 					unsigned interface);
210 	void			(*disable)(struct usb_function *);
211 	int			(*setup)(struct usb_function *,
212 					const struct usb_ctrlrequest *);
213 	bool			(*req_match)(struct usb_function *,
214 					const struct usb_ctrlrequest *,
215 					bool config0);
216 	void			(*suspend)(struct usb_function *);
217 	void			(*resume)(struct usb_function *);
218 
219 	/* USB 3.0 additions */
220 	int			(*get_status)(struct usb_function *);
221 	int			(*func_suspend)(struct usb_function *,
222 						u8 suspend_opt);
223 	/* private: */
224 	/* internals */
225 	struct list_head		list;
226 	DECLARE_BITMAP(endpoints, 32);
227 	const struct usb_function_instance *fi;
228 
229 	unsigned int		bind_deactivated:1;
230 };
231 
232 int usb_add_function(struct usb_configuration *, struct usb_function *);
233 
234 int usb_function_deactivate(struct usb_function *);
235 int usb_function_activate(struct usb_function *);
236 
237 int usb_interface_id(struct usb_configuration *, struct usb_function *);
238 
239 int config_ep_by_speed_and_alt(struct usb_gadget *g, struct usb_function *f,
240 				struct usb_ep *_ep, u8 alt);
241 
242 int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f,
243 			struct usb_ep *_ep);
244 
245 #define	MAX_CONFIG_INTERFACES		16	/* arbitrary; max 255 */
246 
247 /**
248  * struct usb_configuration - represents one gadget configuration
249  * @label: For diagnostics, describes the configuration.
250  * @strings: Tables of strings, keyed by identifiers assigned during @bind()
251  *	and by language IDs provided in control requests.
252  * @descriptors: Table of descriptors preceding all function descriptors.
253  *	Examples include OTG and vendor-specific descriptors.
254  * @unbind: Reverses @bind; called as a side effect of unregistering the
255  *	driver which added this configuration.
256  * @setup: Used to delegate control requests that aren't handled by standard
257  *	device infrastructure or directed at a specific interface.
258  * @bConfigurationValue: Copied into configuration descriptor.
259  * @iConfiguration: Copied into configuration descriptor.
260  * @bmAttributes: Copied into configuration descriptor.
261  * @MaxPower: Power consumption in mA. Used to compute bMaxPower in the
262  *	configuration descriptor after considering the bus speed.
263  * @cdev: assigned by @usb_add_config() before calling @bind(); this is
264  *	the device associated with this configuration.
265  *
266  * Configurations are building blocks for gadget drivers structured around
267  * function drivers.  Simple USB gadgets require only one function and one
268  * configuration, and handle dual-speed hardware by always providing the same
269  * functionality.  Slightly more complex gadgets may have more than one
270  * single-function configuration at a given speed; or have configurations
271  * that only work at one speed.
272  *
273  * Composite devices are, by definition, ones with configurations which
274  * include more than one function.
275  *
276  * The lifecycle of a usb_configuration includes allocation, initialization
277  * of the fields described above, and calling @usb_add_config() to set up
278  * internal data and bind it to a specific device.  The configuration's
279  * @bind() method is then used to initialize all the functions and then
280  * call @usb_add_function() for them.
281  *
282  * Those functions would normally be independent of each other, but that's
283  * not mandatory.  CDC WMC devices are an example where functions often
284  * depend on other functions, with some functions subsidiary to others.
285  * Such interdependency may be managed in any way, so long as all of the
286  * descriptors complete by the time the composite driver returns from
287  * its bind() routine.
288  */
289 struct usb_configuration {
290 	const char			*label;
291 	struct usb_gadget_strings	**strings;
292 	const struct usb_descriptor_header **descriptors;
293 
294 	/* REVISIT:  bind() functions can be marked __init, which
295 	 * makes trouble for section mismatch analysis.  See if
296 	 * we can't restructure things to avoid mismatching...
297 	 */
298 
299 	/* configuration management: unbind/setup */
300 	void			(*unbind)(struct usb_configuration *);
301 	int			(*setup)(struct usb_configuration *,
302 					const struct usb_ctrlrequest *);
303 
304 	/* fields in the config descriptor */
305 	u8			bConfigurationValue;
306 	u8			iConfiguration;
307 	u8			bmAttributes;
308 	u16			MaxPower;
309 
310 	struct usb_composite_dev	*cdev;
311 
312 	/* private: */
313 	/* internals */
314 	struct list_head	list;
315 	struct list_head	functions;
316 	u8			next_interface_id;
317 	unsigned		superspeed:1;
318 	unsigned		highspeed:1;
319 	unsigned		fullspeed:1;
320 	unsigned		superspeed_plus:1;
321 	struct usb_function	*interface[MAX_CONFIG_INTERFACES];
322 };
323 
324 int usb_add_config(struct usb_composite_dev *,
325 		struct usb_configuration *,
326 		int (*)(struct usb_configuration *));
327 
328 void usb_remove_config(struct usb_composite_dev *,
329 		struct usb_configuration *);
330 
331 /* predefined index for usb_composite_driver */
332 enum {
333 	USB_GADGET_MANUFACTURER_IDX	= 0,
334 	USB_GADGET_PRODUCT_IDX,
335 	USB_GADGET_SERIAL_IDX,
336 	USB_GADGET_FIRST_AVAIL_IDX,
337 };
338 
339 /**
340  * struct usb_composite_driver - groups configurations into a gadget
341  * @name: For diagnostics, identifies the driver.
342  * @dev: Template descriptor for the device, including default device
343  *	identifiers.
344  * @strings: tables of strings, keyed by identifiers assigned during @bind
345  *	and language IDs provided in control requests. Note: The first entries
346  *	are predefined. The first entry that may be used is
347  *	USB_GADGET_FIRST_AVAIL_IDX
348  * @max_speed: Highest speed the driver supports.
349  * @needs_serial: set to 1 if the gadget needs userspace to provide
350  * 	a serial number.  If one is not provided, warning will be printed.
351  * @bind: (REQUIRED) Used to allocate resources that are shared across the
352  *	whole device, such as string IDs, and add its configurations using
353  *	@usb_add_config(). This may fail by returning a negative errno
354  *	value; it should return zero on successful initialization.
355  * @unbind: Reverses @bind; called as a side effect of unregistering
356  *	this driver.
357  * @disconnect: optional driver disconnect method
358  * @suspend: Notifies when the host stops sending USB traffic,
359  *	after function notifications
360  * @resume: Notifies configuration when the host restarts USB traffic,
361  *	before function notifications
362  * @gadget_driver: Gadget driver controlling this driver
363  *
364  * Devices default to reporting self powered operation.  Devices which rely
365  * on bus powered operation should report this in their @bind method.
366  *
367  * Before returning from @bind, various fields in the template descriptor
368  * may be overridden.  These include the idVendor/idProduct/bcdDevice values
369  * normally to bind the appropriate host side driver, and the three strings
370  * (iManufacturer, iProduct, iSerialNumber) normally used to provide user
371  * meaningful device identifiers.  (The strings will not be defined unless
372  * they are defined in @dev and @strings.)  The correct ep0 maxpacket size
373  * is also reported, as defined by the underlying controller driver.
374  */
375 struct usb_composite_driver {
376 	const char				*name;
377 	const struct usb_device_descriptor	*dev;
378 	struct usb_gadget_strings		**strings;
379 	enum usb_device_speed			max_speed;
380 	unsigned		needs_serial:1;
381 
382 	int			(*bind)(struct usb_composite_dev *cdev);
383 	int			(*unbind)(struct usb_composite_dev *);
384 
385 	void			(*disconnect)(struct usb_composite_dev *);
386 
387 	/* global suspend hooks */
388 	void			(*suspend)(struct usb_composite_dev *);
389 	void			(*resume)(struct usb_composite_dev *);
390 	struct usb_gadget_driver		gadget_driver;
391 };
392 
393 extern int usb_composite_probe(struct usb_composite_driver *driver);
394 extern void usb_composite_unregister(struct usb_composite_driver *driver);
395 
396 /**
397  * module_usb_composite_driver() - Helper macro for registering a USB gadget
398  * composite driver
399  * @__usb_composite_driver: usb_composite_driver struct
400  *
401  * Helper macro for USB gadget composite drivers which do not do anything
402  * special in module init/exit. This eliminates a lot of boilerplate. Each
403  * module may only use this macro once, and calling it replaces module_init()
404  * and module_exit()
405  */
406 #define module_usb_composite_driver(__usb_composite_driver) \
407 	module_driver(__usb_composite_driver, usb_composite_probe, \
408 		       usb_composite_unregister)
409 
410 extern void usb_composite_setup_continue(struct usb_composite_dev *cdev);
411 extern int composite_dev_prepare(struct usb_composite_driver *composite,
412 		struct usb_composite_dev *cdev);
413 extern int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
414 					 struct usb_ep *ep0);
415 void composite_dev_cleanup(struct usb_composite_dev *cdev);
416 
to_cdriver(struct usb_gadget_driver * gdrv)417 static inline struct usb_composite_driver *to_cdriver(
418 		struct usb_gadget_driver *gdrv)
419 {
420 	return container_of(gdrv, struct usb_composite_driver, gadget_driver);
421 }
422 
423 #define OS_STRING_QW_SIGN_LEN		14
424 #define OS_STRING_IDX			0xEE
425 
426 /**
427  * struct usb_composite_dev - represents one composite usb gadget
428  * @gadget: read-only, abstracts the gadget's usb peripheral controller
429  * @req: used for control responses; buffer is pre-allocated
430  * @os_desc_req: used for OS descriptors responses; buffer is pre-allocated
431  * @config: the currently active configuration
432  * @qw_sign: qwSignature part of the OS string
433  * @b_vendor_code: bMS_VendorCode part of the OS string
434  * @use_os_string: false by default, interested gadgets set it
435  * @bcd_webusb_version: 0x0100 by default, WebUSB specification version
436  * @b_webusb_vendor_code: 0x0 by default, vendor code for WebUSB
437  * @landing_page: empty by default, landing page to announce in WebUSB
438  * @use_webusb:: false by default, interested gadgets set it
439  * @os_desc_config: the configuration to be used with OS descriptors
440  * @setup_pending: true when setup request is queued but not completed
441  * @os_desc_pending: true when os_desc request is queued but not completed
442  *
443  * One of these devices is allocated and initialized before the
444  * associated device driver's bind() is called.
445  *
446  * OPEN ISSUE:  it appears that some WUSB devices will need to be
447  * built by combining a normal (wired) gadget with a wireless one.
448  * This revision of the gadget framework should probably try to make
449  * sure doing that won't hurt too much.
450  *
451  * One notion for how to handle Wireless USB devices involves:
452  *
453  * (a) a second gadget here, discovery mechanism TBD, but likely
454  *     needing separate "register/unregister WUSB gadget" calls;
455  * (b) updates to usb_gadget to include flags "is it wireless",
456  *     "is it wired", plus (presumably in a wrapper structure)
457  *     bandgroup and PHY info;
458  * (c) presumably a wireless_ep wrapping a usb_ep, and reporting
459  *     wireless-specific parameters like maxburst and maxsequence;
460  * (d) configurations that are specific to wireless links;
461  * (e) function drivers that understand wireless configs and will
462  *     support wireless for (additional) function instances;
463  * (f) a function to support association setup (like CBAF), not
464  *     necessarily requiring a wireless adapter;
465  * (g) composite device setup that can create one or more wireless
466  *     configs, including appropriate association setup support;
467  * (h) more, TBD.
468  */
469 struct usb_composite_dev {
470 	struct usb_gadget		*gadget;
471 	struct usb_request		*req;
472 	struct usb_request		*os_desc_req;
473 
474 	struct usb_configuration	*config;
475 
476 	/* OS String is a custom (yet popular) extension to the USB standard. */
477 	u8				qw_sign[OS_STRING_QW_SIGN_LEN];
478 	u8				b_vendor_code;
479 	struct usb_configuration	*os_desc_config;
480 	unsigned int			use_os_string:1;
481 
482 	/* WebUSB */
483 	u16				bcd_webusb_version;
484 	u8				b_webusb_vendor_code;
485 	char				landing_page[WEBUSB_URL_RAW_MAX_LENGTH];
486 	unsigned int			use_webusb:1;
487 
488 	/* private: */
489 	/* internals */
490 	unsigned int			suspended:1;
491 	struct usb_device_descriptor	desc;
492 	struct list_head		configs;
493 	struct list_head		gstrings;
494 	struct usb_composite_driver	*driver;
495 	u8				next_string_id;
496 	char				*def_manufacturer;
497 	struct usb_string		*usb_strings;
498 
499 	/* the gadget driver won't enable the data pullup
500 	 * while the deactivation count is nonzero.
501 	 */
502 	unsigned			deactivations;
503 
504 	/* the composite driver won't complete the control transfer's
505 	 * data/status stages till delayed_status is zero.
506 	 */
507 	int				delayed_status;
508 
509 	/* protects deactivations and delayed_status counts*/
510 	spinlock_t			lock;
511 
512 	/* public: */
513 	unsigned int			setup_pending:1;
514 	unsigned int			os_desc_pending:1;
515 };
516 
517 extern int usb_string_id(struct usb_composite_dev *c);
518 extern int usb_string_ids_tab(struct usb_composite_dev *c,
519 			      struct usb_string *str);
520 extern struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
521 		struct usb_gadget_strings **sp, unsigned n_strings);
522 
523 extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n);
524 
525 extern void composite_disconnect(struct usb_gadget *gadget);
526 extern void composite_reset(struct usb_gadget *gadget);
527 
528 extern int composite_setup(struct usb_gadget *gadget,
529 		const struct usb_ctrlrequest *ctrl);
530 extern void composite_suspend(struct usb_gadget *gadget);
531 extern void composite_resume(struct usb_gadget *gadget);
532 
533 /*
534  * Some systems will need runtime overrides for the  product identifiers
535  * published in the device descriptor, either numbers or strings or both.
536  * String parameters are in UTF-8 (superset of ASCII's 7 bit characters).
537  */
538 struct usb_composite_overwrite {
539 	u16	idVendor;
540 	u16	idProduct;
541 	u16	bcdDevice;
542 	char	*serial_number;
543 	char	*manufacturer;
544 	char	*product;
545 };
546 #define USB_GADGET_COMPOSITE_OPTIONS()					\
547 	static struct usb_composite_overwrite coverwrite;		\
548 									\
549 	module_param_named(idVendor, coverwrite.idVendor, ushort, S_IRUGO); \
550 	MODULE_PARM_DESC(idVendor, "USB Vendor ID");			\
551 									\
552 	module_param_named(idProduct, coverwrite.idProduct, ushort, S_IRUGO); \
553 	MODULE_PARM_DESC(idProduct, "USB Product ID");			\
554 									\
555 	module_param_named(bcdDevice, coverwrite.bcdDevice, ushort, S_IRUGO); \
556 	MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)");	\
557 									\
558 	module_param_named(iSerialNumber, coverwrite.serial_number, charp, \
559 			S_IRUGO); \
560 	MODULE_PARM_DESC(iSerialNumber, "SerialNumber string");		\
561 									\
562 	module_param_named(iManufacturer, coverwrite.manufacturer, charp, \
563 			S_IRUGO); \
564 	MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string");	\
565 									\
566 	module_param_named(iProduct, coverwrite.product, charp, S_IRUGO); \
567 	MODULE_PARM_DESC(iProduct, "USB Product string")
568 
569 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
570 		struct usb_composite_overwrite *covr);
571 
get_default_bcdDevice(void)572 static inline u16 get_default_bcdDevice(void)
573 {
574 	u16 bcdDevice;
575 
576 	bcdDevice = bin2bcd(LINUX_VERSION_MAJOR) << 8;
577 	bcdDevice |= bin2bcd(LINUX_VERSION_PATCHLEVEL);
578 	return bcdDevice;
579 }
580 
581 struct usb_function_driver {
582 	const char *name;
583 	struct module *mod;
584 	struct list_head list;
585 	struct usb_function_instance *(*alloc_inst)(void);
586 	struct usb_function *(*alloc_func)(struct usb_function_instance *inst);
587 };
588 
589 struct usb_function_instance {
590 	struct config_group group;
591 	struct list_head cfs_list;
592 	struct usb_function_driver *fd;
593 	int (*set_inst_name)(struct usb_function_instance *inst,
594 			      const char *name);
595 	void (*free_func_inst)(struct usb_function_instance *inst);
596 };
597 
598 void usb_function_unregister(struct usb_function_driver *f);
599 int usb_function_register(struct usb_function_driver *newf);
600 void usb_put_function_instance(struct usb_function_instance *fi);
601 void usb_put_function(struct usb_function *f);
602 struct usb_function_instance *usb_get_function_instance(const char *name);
603 struct usb_function *usb_get_function(struct usb_function_instance *fi);
604 
605 struct usb_configuration *usb_get_config(struct usb_composite_dev *cdev,
606 		int val);
607 int usb_add_config_only(struct usb_composite_dev *cdev,
608 		struct usb_configuration *config);
609 void usb_remove_function(struct usb_configuration *c, struct usb_function *f);
610 
611 #define DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc)		\
612 	static struct usb_function_driver _name ## usb_func = {		\
613 		.name = __stringify(_name),				\
614 		.mod  = THIS_MODULE,					\
615 		.alloc_inst = _inst_alloc,				\
616 		.alloc_func = _func_alloc,				\
617 	};								\
618 	MODULE_ALIAS("usbfunc:"__stringify(_name));
619 
620 #define DECLARE_USB_FUNCTION_INIT(_name, _inst_alloc, _func_alloc)	\
621 	DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc)		\
622 	static int __init _name ## mod_init(void)			\
623 	{								\
624 		return usb_function_register(&_name ## usb_func);	\
625 	}								\
626 	static void __exit _name ## mod_exit(void)			\
627 	{								\
628 		usb_function_unregister(&_name ## usb_func);		\
629 	}								\
630 	module_init(_name ## mod_init);					\
631 	module_exit(_name ## mod_exit)
632 
633 /* messaging utils */
634 #define DBG(d, fmt, args...) \
635 	dev_dbg(&(d)->gadget->dev , fmt , ## args)
636 #define VDBG(d, fmt, args...) \
637 	dev_vdbg(&(d)->gadget->dev , fmt , ## args)
638 #define ERROR(d, fmt, args...) \
639 	dev_err(&(d)->gadget->dev , fmt , ## args)
640 #define WARNING(d, fmt, args...) \
641 	dev_warn(&(d)->gadget->dev , fmt , ## args)
642 #define INFO(d, fmt, args...) \
643 	dev_info(&(d)->gadget->dev , fmt , ## args)
644 
645 #endif	/* __LINUX_USB_COMPOSITE_H */
646