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 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
20 */
21
22#ifndef __LINUX_USB_COMPOSITE_H
23#define __LINUX_USB_COMPOSITE_H
24
25/*
26 * This framework is an optional layer on top of the USB Gadget interface,
27 * making it easier to build (a) Composite devices, supporting multiple
28 * functions within any single configuration, and (b) Multi-configuration
29 * devices, also supporting multiple functions but without necessarily
30 * having more than one function per configuration.
31 *
32 * Example:  a device with a single configuration supporting both network
33 * link and mass storage functions is a composite device.  Those functions
34 * might alternatively be packaged in individual configurations, but in
35 * the composite model the host can use both functions at the same time.
36 */
37
38#include <linux/bcd.h>
39#include <linux/version.h>
40#include <linux/usb/ch9.h>
41#include <linux/usb/gadget.h>
42#include <linux/log2.h>
43#include <linux/configfs.h>
44
45/*
46 * USB function drivers should return USB_GADGET_DELAYED_STATUS if they
47 * wish to delay the data/status stages of the control transfer till they
48 * are ready. The control transfer will then be kept from completing till
49 * all the function drivers that requested for USB_GADGET_DELAYED_STAUS
50 * invoke usb_composite_setup_continue().
51 */
52#define USB_GADGET_DELAYED_STATUS 0x7fff /* Impossibly large value */
53
54/* big enough to hold our biggest descriptor */
55#define USB_COMP_EP0_BUFSIZ 4096
56
57/* OS feature descriptor length <= 4kB */
58#define USB_COMP_EP0_OS_DESC_BUFSIZ 4096
59
60#define USB_MS_TO_HS_INTERVAL(x) (ilog2(((x)*1000 / 125)) + 1)
61struct usb_configuration;
62
63/**
64 * struct usb_os_desc_ext_prop - describes one "Extended Property"
65 * @entry: used to keep a list of extended properties
66 * @type: Extended Property type
67 * @name_len: Extended Property unicode name length, including terminating '\0'
68 * @name: Extended Property name
69 * @data_len: Length of Extended Property blob (for unicode store double len)
70 * @data: Extended Property blob
71 * @item: Represents this Extended Property in configfs
72 */
73struct usb_os_desc_ext_prop {
74    struct list_head entry;
75    u8 type;
76    int name_len;
77    char *name;
78    int data_len;
79    char *data;
80    struct config_item item;
81};
82
83/**
84 * struct usb_os_desc - describes OS descriptors associated with one interface
85 * @ext_compat_id: 16 bytes of "Compatible ID" and "Subcompatible ID"
86 * @ext_prop: Extended Properties list
87 * @ext_prop_len: Total length of Extended Properties blobs
88 * @ext_prop_count: Number of Extended Properties
89 * @opts_mutex: Optional mutex protecting config data of a usb_function_instance
90 * @group: Represents OS descriptors associated with an interface in configfs
91 * @owner: Module associated with this OS descriptor
92 */
93struct usb_os_desc {
94    char *ext_compat_id;
95    struct list_head ext_prop;
96    int ext_prop_len;
97    int ext_prop_count;
98    struct mutex *opts_mutex;
99    struct config_group group;
100    struct module *owner;
101};
102
103/**
104 * struct usb_os_desc_table - describes OS descriptors associated with one
105 * interface of a usb_function
106 * @if_id: Interface id
107 * @os_desc: "Extended Compatibility ID" and "Extended Properties" of the
108 *    interface
109 *
110 * Each interface can have at most one "Extended Compatibility ID" and a
111 * number of "Extended Properties".
112 */
113struct usb_os_desc_table {
114    int if_id;
115    struct usb_os_desc *os_desc;
116};
117
118/**
119 * struct usb_function - describes one function of a configuration
120 * @name: For diagnostics, identifies the function.
121 * @strings: tables of strings, keyed by identifiers assigned during bind()
122 *    and by language IDs provided in control requests
123 * @fs_descriptors: Table of full (or low) speed descriptors, using interface and
124 *    string identifiers assigned during @bind().  If this pointer is null,
125 *    the function will not be available at full speed (or at low speed).
126 * @hs_descriptors: Table of high speed descriptors, using interface and
127 *    string identifiers assigned during @bind().  If this pointer is null,
128 *    the function will not be available at high speed.
129 * @ss_descriptors: Table of super speed descriptors, using interface and
130 *    string identifiers assigned during @bind(). If this
131 *    pointer is null after initiation, the function will not
132 *    be available at super speed.
133 * @ssp_descriptors: Table of super speed plus descriptors, using
134 *    interface and string identifiers assigned during @bind(). If
135 *    this pointer is null after initiation, the function will not
136 *    be available at super speed plus.
137 * @config: assigned when @usb_add_function() is called; this is the
138 *    configuration with which this function is associated.
139 * @os_desc_table: Table of (interface id, os descriptors) pairs. The function
140 *    can expose more than one interface. If an interface is a member of
141 *    an IAD, only the first interface of IAD has its entry in the table.
142 * @os_desc_n: Number of entries in os_desc_table
143 * @bind: Before the gadget can register, all of its functions bind() to the
144 *    available resources including string and interface identifiers used
145 *    in interface or class descriptors; endpoints; I/O buffers; and so on.
146 * @unbind: Reverses @bind; called as a side effect of unregistering the
147 *    driver which added this function.
148 * @free_func: free the struct usb_function.
149 * @mod: (internal) points to the module that created this structure.
150 * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may
151 *    initialize usb_ep.driver data at this time (when it is used).
152 *    Note that setting an interface to its current altsetting resets
153 *    interface state, and that all interfaces have a disabled state.
154 * @get_alt: Returns the active altsetting.  If this is not provided,
155 *    then only altsetting zero is supported.
156 * @disable: (REQUIRED) Indicates the function should be disabled.  Reasons
157 *    include host resetting or reconfiguring the gadget, and disconnection.
158 * @setup: Used for interface-specific control requests.
159 * @req_match: Tests if a given class request can be handled by this function.
160 * @suspend: Notifies functions when the host stops sending USB traffic.
161 * @resume: Notifies functions when the host restarts USB traffic.
162 * @get_status: Returns function status as a reply to
163 *    GetStatus() request when the recipient is Interface.
164 * @func_suspend: callback to be called when
165 *    SetFeature(FUNCTION_SUSPEND) is reseived
166 *
167 * A single USB function uses one or more interfaces, and should in most
168 * cases support operation at both full and high speeds.  Each function is
169 * associated by @usb_add_function() with a one configuration; that function
170 * causes @bind() to be called so resources can be allocated as part of
171 * setting up a gadget driver.  Those resources include endpoints, which
172 * should be allocated using @usb_ep_autoconfig().
173 *
174 * To support dual speed operation, a function driver provides descriptors
175 * for both high and full speed operation.  Except in rare cases that don't
176 * involve bulk endpoints, each speed needs different endpoint descriptors.
177 *
178 * Function drivers choose their own strategies for managing instance data.
179 * The simplest strategy just declares it "static', which means the function
180 * can only be activated once.  If the function needs to be exposed in more
181 * than one configuration at a given speed, it needs to support multiple
182 * usb_function structures (one for each configuration).
183 *
184 * A more complex strategy might encapsulate a @usb_function structure inside
185 * a driver-specific instance structure to allows multiple activations.  An
186 * example of multiple activations might be a CDC ACM function that supports
187 * two or more distinct instances within the same configuration, providing
188 * several independent logical data links to a USB host.
189 */
190
191struct usb_function {
192    const char *name;
193    struct usb_gadget_strings **strings;
194    struct usb_descriptor_header **fs_descriptors;
195    struct usb_descriptor_header **hs_descriptors;
196    struct usb_descriptor_header **ss_descriptors;
197    struct usb_descriptor_header **ssp_descriptors;
198
199    struct usb_configuration *config;
200
201    struct usb_os_desc_table *os_desc_table;
202    unsigned os_desc_n;
203
204    /* REVISIT:  bind() functions can be marked __init, which
205     * makes trouble for section mismatch analysis.  See if
206     * we can't restructure things to avoid mismatching.
207     * Related:  unbind() may kfree() but bind() won't...
208     */
209
210    /* configuration management:  bind/unbind */
211    int (*bind)(struct usb_configuration *, struct usb_function *);
212    void (*unbind)(struct usb_configuration *, struct usb_function *);
213    void (*free_func)(struct usb_function *f);
214    struct module *mod;
215
216    /* runtime state management */
217    int (*set_alt)(struct usb_function *, unsigned interface, unsigned alt);
218    int (*get_alt)(struct usb_function *, unsigned interface);
219    void (*disable)(struct usb_function *);
220    int (*setup)(struct usb_function *, const struct usb_ctrlrequest *);
221    bool (*req_match)(struct usb_function *, const struct usb_ctrlrequest *, bool config0);
222    void (*suspend)(struct usb_function *);
223    void (*resume)(struct usb_function *);
224
225    /* USB 3.0 additions */
226    int (*get_status)(struct usb_function *);
227    int (*func_suspend)(struct usb_function *, u8 suspend_opt);
228    /* private: */
229    /* internals */
230    struct list_head list;
231    DECLARE_BITMAP(endpoints, 32);
232    const struct usb_function_instance *fi;
233
234    unsigned int bind_deactivated : 1;
235};
236
237int usb_add_function(struct usb_configuration *, struct usb_function *);
238
239int usb_function_deactivate(struct usb_function *);
240int usb_function_activate(struct usb_function *);
241
242int usb_interface_id(struct usb_configuration *, struct usb_function *);
243
244int config_ep_by_speed_and_alt(struct usb_gadget *g, struct usb_function *f, struct usb_ep *_ep, u8 alt);
245
246int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f, struct usb_ep *_ep);
247
248#define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */
249
250/**
251 * struct usb_configuration - represents one gadget configuration
252 * @label: For diagnostics, describes the configuration.
253 * @strings: Tables of strings, keyed by identifiers assigned during @bind()
254 *    and by language IDs provided in control requests.
255 * @descriptors: Table of descriptors preceding all function descriptors.
256 *    Examples include OTG and vendor-specific descriptors.
257 * @unbind: Reverses @bind; called as a side effect of unregistering the
258 *    driver which added this configuration.
259 * @setup: Used to delegate control requests that aren't handled by standard
260 *    device infrastructure or directed at a specific interface.
261 * @bConfigurationValue: Copied into configuration descriptor.
262 * @iConfiguration: Copied into configuration descriptor.
263 * @bmAttributes: Copied into configuration descriptor.
264 * @MaxPower: Power consumtion in mA. Used to compute bMaxPower in the
265 *    configuration descriptor after considering the bus speed.
266 * @cdev: assigned by @usb_add_config() before calling @bind(); this is
267 *    the device associated with this configuration.
268 *
269 * Configurations are building blocks for gadget drivers structured around
270 * function drivers.  Simple USB gadgets require only one function and one
271 * configuration, and handle dual-speed hardware by always providing the same
272 * functionality.  Slightly more complex gadgets may have more than one
273 * single-function configuration at a given speed; or have configurations
274 * that only work at one speed.
275 *
276 * Composite devices are, by definition, ones with configurations which
277 * include more than one function.
278 *
279 * The lifecycle of a usb_configuration includes allocation, initialization
280 * of the fields described above, and calling @usb_add_config() to set up
281 * internal data and bind it to a specific device.  The configuration's
282 * @bind() method is then used to initialize all the functions and then
283 * call @usb_add_function() for them.
284 *
285 * Those functions would normally be independent of each other, but that's
286 * not mandatory.  CDC WMC devices are an example where functions often
287 * depend on other functions, with some functions subsidiary to others.
288 * Such interdependency may be managed in any way, so long as all of the
289 * descriptors complete by the time the composite driver returns from
290 * its bind() routine.
291 */
292struct usb_configuration {
293    const char *label;
294    struct usb_gadget_strings **strings;
295    const struct usb_descriptor_header **descriptors;
296
297    /* REVISIT:  bind() functions can be marked __init, which
298     * makes trouble for section mismatch analysis.  See if
299     * we can't restructure things to avoid mismatching...
300     */
301
302    /* configuration management: unbind/setup */
303    void (*unbind)(struct usb_configuration *);
304    int (*setup)(struct usb_configuration *, const struct usb_ctrlrequest *);
305
306    /* fields in the config descriptor */
307    u8 bConfigurationValue;
308    u8 iConfiguration;
309    u8 bmAttributes;
310    u16 MaxPower;
311
312    struct usb_composite_dev *cdev;
313
314    /* private: */
315    /* internals */
316    struct list_head list;
317    struct list_head functions;
318    u8 next_interface_id;
319    unsigned superspeed : 1;
320    unsigned highspeed : 1;
321    unsigned fullspeed : 1;
322    unsigned superspeed_plus : 1;
323    struct usb_function *interface[MAX_CONFIG_INTERFACES];
324};
325
326int usb_add_config(struct usb_composite_dev *, struct usb_configuration *, int (*)(struct usb_configuration *));
327
328void usb_remove_config(struct usb_composite_dev *, struct usb_configuration *);
329
330/* predefined index for usb_composite_driver */
331enum {
332    USB_GADGET_MANUFACTURER_IDX = 0,
333    USB_GADGET_PRODUCT_IDX,
334    USB_GADGET_SERIAL_IDX,
335    USB_GADGET_FIRST_AVAIL_IDX,
336};
337
338/**
339 * struct usb_composite_driver - groups configurations into a gadget
340 * @name: For diagnostics, identifies the driver.
341 * @dev: Template descriptor for the device, including default device
342 *    identifiers.
343 * @strings: tables of strings, keyed by identifiers assigned during @bind
344 *    and language IDs provided in control requests. Note: The first entries
345 *    are predefined. The first entry that may be used is
346 *    USB_GADGET_FIRST_AVAIL_IDX
347 * @max_speed: Highest speed the driver supports.
348 * @needs_serial: set to 1 if the gadget needs userspace to provide
349 *     a serial number.  If one is not provided, warning will be printed.
350 * @bind: (REQUIRED) Used to allocate resources that are shared across the
351 *    whole device, such as string IDs, and add its configurations using
352 *    @usb_add_config(). This may fail by returning a negative errno
353 *    value; it should return zero on successful initialization.
354 * @unbind: Reverses @bind; called as a side effect of unregistering
355 *    this driver.
356 * @disconnect: optional driver disconnect method
357 * @suspend: Notifies when the host stops sending USB traffic,
358 *    after function notifications
359 * @resume: Notifies configuration when the host restarts USB traffic,
360 *    before function notifications
361 * @gadget_driver: Gadget driver controlling this driver
362 *
363 * Devices default to reporting self powered operation.  Devices which rely
364 * on bus powered operation should report this in their @bind method.
365 *
366 * Before returning from @bind, various fields in the template descriptor
367 * may be overridden.  These include the idVendor/idProduct/bcdDevice values
368 * normally to bind the appropriate host side driver, and the three strings
369 * (iManufacturer, iProduct, iSerialNumber) normally used to provide user
370 * meaningful device identifiers.  (The strings will not be defined unless
371 * they are defined in @dev and @strings.)  The correct ep0 maxpacket size
372 * is also reported, as defined by the underlying controller driver.
373 */
374struct usb_composite_driver {
375    const char *name;
376    const struct usb_device_descriptor *dev;
377    struct usb_gadget_strings **strings;
378    enum usb_device_speed max_speed;
379    unsigned needs_serial : 1;
380
381    int (*bind)(struct usb_composite_dev *cdev);
382    int (*unbind)(struct usb_composite_dev *);
383
384    void (*disconnect)(struct usb_composite_dev *);
385
386    /* global suspend hooks */
387    void (*suspend)(struct usb_composite_dev *);
388    void (*resume)(struct usb_composite_dev *);
389    struct usb_gadget_driver gadget_driver;
390};
391
392extern int usb_composite_probe(struct usb_composite_driver *driver);
393extern void usb_composite_unregister(struct usb_composite_driver *driver);
394
395/**
396 * module_usb_composite_driver() - Helper macro for registering a USB gadget
397 * composite driver
398 * @__usb_composite_driver: usb_composite_driver struct
399 *
400 * Helper macro for USB gadget composite drivers which do not do anything
401 * special in module init/exit. This eliminates a lot of boilerplate. Each
402 * module may only use this macro once, and calling it replaces module_init()
403 * and module_exit()
404 */
405#define module_usb_composite_driver(__usb_composite_driver)                                                            \
406    module_driver(__usb_composite_driver, usb_composite_probe, usb_composite_unregister)
407
408extern void usb_composite_setup_continue(struct usb_composite_dev *cdev);
409extern int composite_dev_prepare(struct usb_composite_driver *composite, struct usb_composite_dev *cdev);
410extern int composite_os_desc_req_prepare(struct usb_composite_dev *cdev, struct usb_ep *ep0);
411void composite_dev_cleanup(struct usb_composite_dev *cdev);
412
413static inline struct usb_composite_driver *to_cdriver(struct usb_gadget_driver *gdrv)
414{
415    return container_of(gdrv, struct usb_composite_driver, gadget_driver);
416}
417
418#define OS_STRING_QW_SIGN_LEN 14
419#define OS_STRING_IDX 0xEE
420
421/**
422 * struct usb_composite_dev - represents one composite usb gadget
423 * @gadget: read-only, abstracts the gadget's usb peripheral controller
424 * @req: used for control responses; buffer is pre-allocated
425 * @os_desc_req: used for OS descriptors responses; buffer is pre-allocated
426 * @config: the currently active configuration
427 * @qw_sign: qwSignature part of the OS string
428 * @b_vendor_code: bMS_VendorCode part of the OS string
429 * @use_os_string: false by default, interested gadgets set it
430 * @os_desc_config: the configuration to be used with OS descriptors
431 * @setup_pending: true when setup request is queued but not completed
432 * @os_desc_pending: true when os_desc request is queued but not completed
433 *
434 * One of these devices is allocated and initialized before the
435 * associated device driver's bind() is called.
436 *
437 * OPEN ISSUE:  it appears that some WUSB devices will need to be
438 * built by combining a normal (wired) gadget with a wireless one.
439 * This revision of the gadget framework should probably try to make
440 * sure doing that won't hurt too much.
441 *
442 * One notion for how to handle Wireless USB devices involves:
443 *
444 * (a) a second gadget here, discovery mechanism, but likely
445 *     needing separate "register/unregister WUSB gadget" calls;
446 * (b) updates to usb_gadget to include flags "is it wireless",
447 *     "is it wired", plus (presumably in a wrapper structure)
448 *     bandgroup and PHY info;
449 * (c) presumably a wireless_ep wrapping a usb_ep, and reporting
450 *     wireless-specific parameters like maxburst and maxsequence;
451 * (d) configurations that are specific to wireless links;
452 * (e) function drivers that understand wireless configs and will
453 *     support wireless for (additional) function instances;
454 * (f) a function to support association setup (like CBAF), not
455 *     necessarily requiring a wireless adapter;
456 * (g) composite device setup that can create one or more wireless
457 *     configs, including appropriate association setup support;
458 * (h) more.
459 */
460struct usb_composite_dev {
461    struct usb_gadget *gadget;
462    struct usb_request *req;
463    struct usb_request *os_desc_req;
464
465    struct usb_configuration *config;
466
467    /* OS String is a custom (yet popular) extension to the USB standard. */
468    u8 qw_sign[OS_STRING_QW_SIGN_LEN];
469    u8 b_vendor_code;
470    struct usb_configuration *os_desc_config;
471    unsigned int use_os_string : 1;
472
473    /* private: */
474    /* internals */
475    unsigned int suspended : 1;
476    struct usb_device_descriptor desc;
477    struct list_head configs;
478    struct list_head gstrings;
479    struct usb_composite_driver *driver;
480    u8 next_string_id;
481    char *def_manufacturer;
482
483    /* the gadget driver won't enable the data pullup
484     * while the deactivation count is nonzero.
485     */
486    unsigned deactivations;
487
488    /* the composite driver won't complete the control transfer's
489     * data/status stages till delayed_status is zero.
490     */
491    int delayed_status;
492
493    /* protects deactivations and delayed_status counts */
494    spinlock_t lock;
495
496    /* public: */
497    unsigned int setup_pending : 1;
498    unsigned int os_desc_pending : 1;
499};
500
501extern int usb_string_id(struct usb_composite_dev *c);
502extern int usb_string_ids_tab(struct usb_composite_dev *c, struct usb_string *str);
503extern struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev, struct usb_gadget_strings **sp,
504                                              unsigned n_strings);
505
506extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n);
507
508extern void composite_disconnect(struct usb_gadget *gadget);
509extern void composite_reset(struct usb_gadget *gadget);
510
511extern int composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl);
512extern void composite_suspend(struct usb_gadget *gadget);
513extern void composite_resume(struct usb_gadget *gadget);
514
515/*
516 * Some systems will need runtime overrides for the  product identifiers
517 * published in the device descriptor, either numbers or strings or both.
518 * String parameters are in UTF-8 (superset of ASCII's 7 bit characters).
519 */
520struct usb_composite_overwrite {
521    u16 idVendor;
522    u16 idProduct;
523    u16 bcdDevice;
524    char *serial_number;
525    char *manufacturer;
526    char *product;
527};
528#define USB_GADGET_COMPOSITE_OPTIONS()                                                                                 \
529    static struct usb_composite_overwrite coverwrite;                                                                  \
530                                                                                                                       \
531    module_param_named(idVendor, coverwrite.idVendor, ushort, S_IRUGO);                                                \
532    MODULE_PARM_DESC(idVendor, "USB Vendor ID");                                                                       \
533                                                                                                                       \
534    module_param_named(idProduct, coverwrite.idProduct, ushort, S_IRUGO);                                              \
535    MODULE_PARM_DESC(idProduct, "USB Product ID");                                                                     \
536                                                                                                                       \
537    module_param_named(bcdDevice, coverwrite.bcdDevice, ushort, S_IRUGO);                                              \
538    MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)");                                                           \
539                                                                                                                       \
540    module_param_named(iSerialNumber, coverwrite.serial_number, charp, S_IRUGO);                                       \
541    MODULE_PARM_DESC(iSerialNumber, "SerialNumber string");                                                            \
542                                                                                                                       \
543    module_param_named(iManufacturer, coverwrite.manufacturer, charp, S_IRUGO);                                        \
544    MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string");                                                        \
545                                                                                                                       \
546    module_param_named(iProduct, coverwrite.product, charp, S_IRUGO);                                                  \
547    MODULE_PARM_DESC(iProduct, "USB Product string")
548
549void usb_composite_overwrite_options(struct usb_composite_dev *cdev, struct usb_composite_overwrite *covr);
550
551static inline u16 get_default_bcdDevice(void)
552{
553    u16 bcdDevice;
554
555    bcdDevice = bin2bcd(((LINUX_VERSION_CODE >> 0x10) & 0xff)) << 0x8;
556    bcdDevice |= bin2bcd(((LINUX_VERSION_CODE >> 0x8) & 0xff));
557    return bcdDevice;
558}
559
560struct usb_function_driver {
561    const char *name;
562    struct module *mod;
563    struct list_head list;
564    struct usb_function_instance *(*alloc_inst)(void);
565    struct usb_function *(*alloc_func)(struct usb_function_instance *inst);
566};
567
568struct usb_function_instance {
569    struct config_group group;
570    struct list_head cfs_list;
571    struct usb_function_driver *fd;
572    struct usb_function *f;
573    int (*set_inst_name)(struct usb_function_instance *inst, const char *name);
574    void (*free_func_inst)(struct usb_function_instance *inst);
575};
576
577void usb_function_unregister(struct usb_function_driver *f);
578int usb_function_register(struct usb_function_driver *newf);
579void usb_put_function_instance(struct usb_function_instance *fi);
580void usb_put_function(struct usb_function *f);
581struct usb_function_instance *usb_get_function_instance(const char *name);
582struct usb_function *usb_get_function(struct usb_function_instance *fi);
583
584struct usb_configuration *usb_get_config(struct usb_composite_dev *cdev, int val);
585int usb_add_config_only(struct usb_composite_dev *cdev, struct usb_configuration *config);
586void usb_remove_function(struct usb_configuration *c, struct usb_function *f);
587
588#define DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc)                                                          \
589    static struct usb_function_driver _name##usb_func = {                                                              \
590        .name = __stringify(_name),                                                                                    \
591        .mod = THIS_MODULE,                                                                                            \
592        .alloc_inst = (_inst_alloc),                                                                                   \
593        .alloc_func = (_func_alloc),                                                                                   \
594    };                                                                                                                 \
595    MODULE_ALIAS("usbfunc:"__stringify(_name));
596
597#define DECLARE_USB_FUNCTION_INIT(_name, _inst_alloc, _func_alloc)                                                     \
598    DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc)                                                              \
599    static int __init _name##mod_init(void)                                                                            \
600    {                                                                                                                  \
601        return usb_function_register(&_name##usb_func);                                                                \
602    }                                                                                                                  \
603    static void __exit _name##mod_exit(void)                                                                           \
604    {                                                                                                                  \
605        usb_function_unregister(&_name##usb_func);                                                                     \
606    }                                                                                                                  \
607    module_init(_name##mod_init);                                                                                      \
608    module_exit(_name##mod_exit)
609
610/* messaging utils */
611#define DBG(d, fmt, args...) dev_dbg(&(d)->gadget->dev, fmt, ##args)
612#define VDBG(d, fmt, args...) dev_vdbg(&(d)->gadget->dev, fmt, ##args)
613#define ERROR(d, fmt, args...) dev_err(&(d)->gadget->dev, fmt, ##args)
614#define WARNING(d, fmt, args...) dev_warn(&(d)->gadget->dev, fmt, ##args)
615#define INFO(d, fmt, args...) dev_info(&(d)->gadget->dev, fmt, ##args)
616
617#endif /* __LINUX_USB_COMPOSITE_H */
618