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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 *,
212 struct usb_function *);
213 void (*unbind)(struct usb_configuration *,
214 struct usb_function *);
215 void (*free_func)(struct usb_function *f);
216 struct module *mod;
217
218 /* runtime state management */
219 int (*set_alt)(struct usb_function *,
220 unsigned interface, unsigned alt);
221 int (*get_alt)(struct usb_function *,
222 unsigned interface);
223 void (*disable)(struct usb_function *);
224 int (*setup)(struct usb_function *,
225 const struct usb_ctrlrequest *);
226 bool (*req_match)(struct usb_function *,
227 const struct usb_ctrlrequest *,
228 bool config0);
229 void (*suspend)(struct usb_function *);
230 void (*resume)(struct usb_function *);
231
232 /* USB 3.0 additions */
233 int (*get_status)(struct usb_function *);
234 int (*func_suspend)(struct usb_function *,
235 u8 suspend_opt);
236 /* private: */
237 /* internals */
238 struct list_head list;
239 DECLARE_BITMAP(endpoints, 32);
240 const struct usb_function_instance *fi;
241
242 unsigned int bind_deactivated:1;
243};
244
245int usb_add_function(struct usb_configuration *, struct usb_function *);
246
247int usb_function_deactivate(struct usb_function *);
248int usb_function_activate(struct usb_function *);
249
250int usb_interface_id(struct usb_configuration *, struct usb_function *);
251
252int config_ep_by_speed_and_alt(struct usb_gadget *g, struct usb_function *f,
253 struct usb_ep *_ep, u8 alt);
254
255int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f,
256 struct usb_ep *_ep);
257
258#define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */
259
260/**
261 * struct usb_configuration - represents one gadget configuration
262 * @label: For diagnostics, describes the configuration.
263 * @strings: Tables of strings, keyed by identifiers assigned during @bind()
264 * and by language IDs provided in control requests.
265 * @descriptors: Table of descriptors preceding all function descriptors.
266 * Examples include OTG and vendor-specific descriptors.
267 * @unbind: Reverses @bind; called as a side effect of unregistering the
268 * driver which added this configuration.
269 * @setup: Used to delegate control requests that aren't handled by standard
270 * device infrastructure or directed at a specific interface.
271 * @bConfigurationValue: Copied into configuration descriptor.
272 * @iConfiguration: Copied into configuration descriptor.
273 * @bmAttributes: Copied into configuration descriptor.
274 * @MaxPower: Power consumtion in mA. Used to compute bMaxPower in the
275 * configuration descriptor after considering the bus speed.
276 * @cdev: assigned by @usb_add_config() before calling @bind(); this is
277 * the device associated with this configuration.
278 *
279 * Configurations are building blocks for gadget drivers structured around
280 * function drivers. Simple USB gadgets require only one function and one
281 * configuration, and handle dual-speed hardware by always providing the same
282 * functionality. Slightly more complex gadgets may have more than one
283 * single-function configuration at a given speed; or have configurations
284 * that only work at one speed.
285 *
286 * Composite devices are, by definition, ones with configurations which
287 * include more than one function.
288 *
289 * The lifecycle of a usb_configuration includes allocation, initialization
290 * of the fields described above, and calling @usb_add_config() to set up
291 * internal data and bind it to a specific device. The configuration's
292 * @bind() method is then used to initialize all the functions and then
293 * call @usb_add_function() for them.
294 *
295 * Those functions would normally be independent of each other, but that's
296 * not mandatory. CDC WMC devices are an example where functions often
297 * depend on other functions, with some functions subsidiary to others.
298 * Such interdependency may be managed in any way, so long as all of the
299 * descriptors complete by the time the composite driver returns from
300 * its bind() routine.
301 */
302struct usb_configuration {
303 const char *label;
304 struct usb_gadget_strings **strings;
305 const struct usb_descriptor_header **descriptors;
306
307 /* REVISIT: bind() functions can be marked __init, which
308 * makes trouble for section mismatch analysis. See if
309 * we can't restructure things to avoid mismatching...
310 */
311
312 /* configuration management: unbind/setup */
313 void (*unbind)(struct usb_configuration *);
314 int (*setup)(struct usb_configuration *,
315 const struct usb_ctrlrequest *);
316
317 /* fields in the config descriptor */
318 u8 bConfigurationValue;
319 u8 iConfiguration;
320 u8 bmAttributes;
321 u16 MaxPower;
322
323 struct usb_composite_dev *cdev;
324
325 /* private: */
326 /* internals */
327 struct list_head list;
328 struct list_head functions;
329 u8 next_interface_id;
330 unsigned superspeed:1;
331 unsigned highspeed:1;
332 unsigned fullspeed:1;
333 unsigned superspeed_plus:1;
334 struct usb_function *interface[MAX_CONFIG_INTERFACES];
335};
336
337int usb_add_config(struct usb_composite_dev *,
338 struct usb_configuration *,
339 int (*)(struct usb_configuration *));
340
341void usb_remove_config(struct usb_composite_dev *,
342 struct usb_configuration *);
343
344/* predefined index for usb_composite_driver */
345enum {
346 USB_GADGET_MANUFACTURER_IDX = 0,
347 USB_GADGET_PRODUCT_IDX,
348 USB_GADGET_SERIAL_IDX,
349 USB_GADGET_FIRST_AVAIL_IDX,
350};
351
352/**
353 * struct usb_composite_driver - groups configurations into a gadget
354 * @name: For diagnostics, identifies the driver.
355 * @dev: Template descriptor for the device, including default device
356 * identifiers.
357 * @strings: tables of strings, keyed by identifiers assigned during @bind
358 * and language IDs provided in control requests. Note: The first entries
359 * are predefined. The first entry that may be used is
360 * USB_GADGET_FIRST_AVAIL_IDX
361 * @max_speed: Highest speed the driver supports.
362 * @needs_serial: set to 1 if the gadget needs userspace to provide
363 * a serial number. If one is not provided, warning will be printed.
364 * @bind: (REQUIRED) Used to allocate resources that are shared across the
365 * whole device, such as string IDs, and add its configurations using
366 * @usb_add_config(). This may fail by returning a negative errno
367 * value; it should return zero on successful initialization.
368 * @unbind: Reverses @bind; called as a side effect of unregistering
369 * this driver.
370 * @disconnect: optional driver disconnect method
371 * @suspend: Notifies when the host stops sending USB traffic,
372 * after function notifications
373 * @resume: Notifies configuration when the host restarts USB traffic,
374 * before function notifications
375 * @gadget_driver: Gadget driver controlling this driver
376 *
377 * Devices default to reporting self powered operation. Devices which rely
378 * on bus powered operation should report this in their @bind method.
379 *
380 * Before returning from @bind, various fields in the template descriptor
381 * may be overridden. These include the idVendor/idProduct/bcdDevice values
382 * normally to bind the appropriate host side driver, and the three strings
383 * (iManufacturer, iProduct, iSerialNumber) normally used to provide user
384 * meaningful device identifiers. (The strings will not be defined unless
385 * they are defined in @dev and @strings.) The correct ep0 maxpacket size
386 * is also reported, as defined by the underlying controller driver.
387 */
388struct usb_composite_driver {
389 const char *name;
390 const struct usb_device_descriptor *dev;
391 struct usb_gadget_strings **strings;
392 enum usb_device_speed max_speed;
393 unsigned needs_serial:1;
394
395 int (*bind)(struct usb_composite_dev *cdev);
396 int (*unbind)(struct usb_composite_dev *);
397
398 void (*disconnect)(struct usb_composite_dev *);
399
400 /* global suspend hooks */
401 void (*suspend)(struct usb_composite_dev *);
402 void (*resume)(struct usb_composite_dev *);
403 struct usb_gadget_driver gadget_driver;
404};
405
406extern int usb_composite_probe(struct usb_composite_driver *driver);
407extern void usb_composite_unregister(struct usb_composite_driver *driver);
408
409/**
410 * module_usb_composite_driver() - Helper macro for registering a USB gadget
411 * composite driver
412 * @__usb_composite_driver: usb_composite_driver struct
413 *
414 * Helper macro for USB gadget composite drivers which do not do anything
415 * special in module init/exit. This eliminates a lot of boilerplate. Each
416 * module may only use this macro once, and calling it replaces module_init()
417 * and module_exit()
418 */
419#define module_usb_composite_driver(__usb_composite_driver) \
420 module_driver(__usb_composite_driver, usb_composite_probe, \
421 usb_composite_unregister)
422
423extern void usb_composite_setup_continue(struct usb_composite_dev *cdev);
424extern int composite_dev_prepare(struct usb_composite_driver *composite,
425 struct usb_composite_dev *cdev);
426extern int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
427 struct usb_ep *ep0);
428void composite_dev_cleanup(struct usb_composite_dev *cdev);
429
430static inline struct usb_composite_driver *to_cdriver(
431 struct usb_gadget_driver *gdrv)
432{
433 return container_of(gdrv, struct usb_composite_driver, gadget_driver);
434}
435
436#define OS_STRING_QW_SIGN_LEN 14
437#define OS_STRING_IDX 0xEE
438
439/**
440 * struct usb_composite_device - represents one composite usb gadget
441 * @gadget: read-only, abstracts the gadget's usb peripheral controller
442 * @req: used for control responses; buffer is pre-allocated
443 * @os_desc_req: used for OS descriptors responses; buffer is pre-allocated
444 * @config: the currently active configuration
445 * @qw_sign: qwSignature part of the OS string
446 * @b_vendor_code: bMS_VendorCode part of the OS string
447 * @use_os_string: false by default, interested gadgets set it
448 * @os_desc_config: the configuration to be used with OS descriptors
449 * @setup_pending: true when setup request is queued but not completed
450 * @os_desc_pending: true when os_desc request is queued but not completed
451 *
452 * One of these devices is allocated and initialized before the
453 * associated device driver's bind() is called.
454 *
455 * OPEN ISSUE: it appears that some WUSB devices will need to be
456 * built by combining a normal (wired) gadget with a wireless one.
457 * This revision of the gadget framework should probably try to make
458 * sure doing that won't hurt too much.
459 *
460 * One notion for how to handle Wireless USB devices involves:
461 *
462 * (a) a second gadget here, discovery mechanism TBD, but likely
463 * needing separate "register/unregister WUSB gadget" calls;
464 * (b) updates to usb_gadget to include flags "is it wireless",
465 * "is it wired", plus (presumably in a wrapper structure)
466 * bandgroup and PHY info;
467 * (c) presumably a wireless_ep wrapping a usb_ep, and reporting
468 * wireless-specific parameters like maxburst and maxsequence;
469 * (d) configurations that are specific to wireless links;
470 * (e) function drivers that understand wireless configs and will
471 * support wireless for (additional) function instances;
472 * (f) a function to support association setup (like CBAF), not
473 * necessarily requiring a wireless adapter;
474 * (g) composite device setup that can create one or more wireless
475 * configs, including appropriate association setup support;
476 * (h) more, TBD.
477 */
478struct usb_composite_dev {
479 struct usb_gadget *gadget;
480 struct usb_request *req;
481 struct usb_request *os_desc_req;
482
483 struct usb_configuration *config;
484
485 /* OS String is a custom (yet popular) extension to the USB standard. */
486 u8 qw_sign[OS_STRING_QW_SIGN_LEN];
487 u8 b_vendor_code;
488 struct usb_configuration *os_desc_config;
489 unsigned int use_os_string:1;
490
491 /* private: */
492 /* internals */
493 unsigned int suspended:1;
494 struct usb_device_descriptor desc;
495 struct list_head configs;
496 struct list_head gstrings;
497 struct usb_composite_driver *driver;
498 u8 next_string_id;
499 char *def_manufacturer;
500
501 /* the gadget driver won't enable the data pullup
502 * while the deactivation count is nonzero.
503 */
504 unsigned deactivations;
505
506 /* the composite driver won't complete the control transfer's
507 * data/status stages till delayed_status is zero.
508 */
509 int delayed_status;
510
511 /* protects deactivations and delayed_status counts*/
512 spinlock_t lock;
513
514 /* public: */
515 unsigned int setup_pending:1;
516 unsigned int os_desc_pending:1;
517};
518
519extern int usb_string_id(struct usb_composite_dev *c);
520extern int usb_string_ids_tab(struct usb_composite_dev *c,
521 struct usb_string *str);
522extern struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
523 struct usb_gadget_strings **sp, unsigned n_strings);
524
525extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n);
526
527extern void composite_disconnect(struct usb_gadget *gadget);
528extern int composite_setup(struct usb_gadget *gadget,
529 const struct usb_ctrlrequest *ctrl);
530extern void composite_suspend(struct usb_gadget *gadget);
531extern 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 */
538struct 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
569void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
570 struct usb_composite_overwrite *covr);
571
572static inline u16 get_default_bcdDevice(void)
573{
574 u16 bcdDevice;
575
576 bcdDevice = bin2bcd((LINUX_VERSION_CODE >> 16 & 0xff)) << 8;
577 bcdDevice |= bin2bcd((LINUX_VERSION_CODE >> 8 & 0xff));
578 return bcdDevice;
579}
580
581struct 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
589struct 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
598void usb_function_unregister(struct usb_function_driver *f);
599int usb_function_register(struct usb_function_driver *newf);
600void usb_put_function_instance(struct usb_function_instance *fi);
601void usb_put_function(struct usb_function *f);
602struct usb_function_instance *usb_get_function_instance(const char *name);
603struct usb_function *usb_get_function(struct usb_function_instance *fi);
604
605struct usb_configuration *usb_get_config(struct usb_composite_dev *cdev,
606 int val);
607int usb_add_config_only(struct usb_composite_dev *cdev,
608 struct usb_configuration *config);
609void 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 */
1/*
2 * composite.h -- framework for usb gadgets which are composite devices
3 *
4 * Copyright (C) 2006-2008 David Brownell
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21#ifndef __LINUX_USB_COMPOSITE_H
22#define __LINUX_USB_COMPOSITE_H
23
24/*
25 * This framework is an optional layer on top of the USB Gadget interface,
26 * making it easier to build (a) Composite devices, supporting multiple
27 * functions within any single configuration, and (b) Multi-configuration
28 * devices, also supporting multiple functions but without necessarily
29 * having more than one function per configuration.
30 *
31 * Example: a device with a single configuration supporting both network
32 * link and mass storage functions is a composite device. Those functions
33 * might alternatively be packaged in individual configurations, but in
34 * the composite model the host can use both functions at the same time.
35 */
36
37#include <linux/usb/ch9.h>
38#include <linux/usb/gadget.h>
39
40/*
41 * USB function drivers should return USB_GADGET_DELAYED_STATUS if they
42 * wish to delay the data/status stages of the control transfer till they
43 * are ready. The control transfer will then be kept from completing till
44 * all the function drivers that requested for USB_GADGET_DELAYED_STAUS
45 * invoke usb_composite_setup_continue().
46 */
47#define USB_GADGET_DELAYED_STATUS 0x7fff /* Impossibly large value */
48
49struct usb_configuration;
50
51/**
52 * struct usb_function - describes one function of a configuration
53 * @name: For diagnostics, identifies the function.
54 * @strings: tables of strings, keyed by identifiers assigned during bind()
55 * and by language IDs provided in control requests
56 * @descriptors: Table of full (or low) speed descriptors, using interface and
57 * string identifiers assigned during @bind(). If this pointer is null,
58 * the function will not be available at full speed (or at low speed).
59 * @hs_descriptors: Table of high speed descriptors, using interface and
60 * string identifiers assigned during @bind(). If this pointer is null,
61 * the function will not be available at high speed.
62 * @ss_descriptors: Table of super speed descriptors, using interface and
63 * string identifiers assigned during @bind(). If this
64 * pointer is null after initiation, the function will not
65 * be available at super speed.
66 * @config: assigned when @usb_add_function() is called; this is the
67 * configuration with which this function is associated.
68 * @bind: Before the gadget can register, all of its functions bind() to the
69 * available resources including string and interface identifiers used
70 * in interface or class descriptors; endpoints; I/O buffers; and so on.
71 * @unbind: Reverses @bind; called as a side effect of unregistering the
72 * driver which added this function.
73 * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may
74 * initialize usb_ep.driver data at this time (when it is used).
75 * Note that setting an interface to its current altsetting resets
76 * interface state, and that all interfaces have a disabled state.
77 * @get_alt: Returns the active altsetting. If this is not provided,
78 * then only altsetting zero is supported.
79 * @disable: (REQUIRED) Indicates the function should be disabled. Reasons
80 * include host resetting or reconfiguring the gadget, and disconnection.
81 * @setup: Used for interface-specific control requests.
82 * @suspend: Notifies functions when the host stops sending USB traffic.
83 * @resume: Notifies functions when the host restarts USB traffic.
84 * @get_status: Returns function status as a reply to
85 * GetStatus() request when the recepient is Interface.
86 * @func_suspend: callback to be called when
87 * SetFeature(FUNCTION_SUSPEND) is reseived
88 *
89 * A single USB function uses one or more interfaces, and should in most
90 * cases support operation at both full and high speeds. Each function is
91 * associated by @usb_add_function() with a one configuration; that function
92 * causes @bind() to be called so resources can be allocated as part of
93 * setting up a gadget driver. Those resources include endpoints, which
94 * should be allocated using @usb_ep_autoconfig().
95 *
96 * To support dual speed operation, a function driver provides descriptors
97 * for both high and full speed operation. Except in rare cases that don't
98 * involve bulk endpoints, each speed needs different endpoint descriptors.
99 *
100 * Function drivers choose their own strategies for managing instance data.
101 * The simplest strategy just declares it "static', which means the function
102 * can only be activated once. If the function needs to be exposed in more
103 * than one configuration at a given speed, it needs to support multiple
104 * usb_function structures (one for each configuration).
105 *
106 * A more complex strategy might encapsulate a @usb_function structure inside
107 * a driver-specific instance structure to allows multiple activations. An
108 * example of multiple activations might be a CDC ACM function that supports
109 * two or more distinct instances within the same configuration, providing
110 * several independent logical data links to a USB host.
111 */
112struct usb_function {
113 const char *name;
114 struct usb_gadget_strings **strings;
115 struct usb_descriptor_header **descriptors;
116 struct usb_descriptor_header **hs_descriptors;
117 struct usb_descriptor_header **ss_descriptors;
118
119 struct usb_configuration *config;
120
121 /* REVISIT: bind() functions can be marked __init, which
122 * makes trouble for section mismatch analysis. See if
123 * we can't restructure things to avoid mismatching.
124 * Related: unbind() may kfree() but bind() won't...
125 */
126
127 /* configuration management: bind/unbind */
128 int (*bind)(struct usb_configuration *,
129 struct usb_function *);
130 void (*unbind)(struct usb_configuration *,
131 struct usb_function *);
132
133 /* runtime state management */
134 int (*set_alt)(struct usb_function *,
135 unsigned interface, unsigned alt);
136 int (*get_alt)(struct usb_function *,
137 unsigned interface);
138 void (*disable)(struct usb_function *);
139 int (*setup)(struct usb_function *,
140 const struct usb_ctrlrequest *);
141 void (*suspend)(struct usb_function *);
142 void (*resume)(struct usb_function *);
143
144 /* USB 3.0 additions */
145 int (*get_status)(struct usb_function *);
146 int (*func_suspend)(struct usb_function *,
147 u8 suspend_opt);
148 /* private: */
149 /* internals */
150 struct list_head list;
151 DECLARE_BITMAP(endpoints, 32);
152};
153
154int usb_add_function(struct usb_configuration *, struct usb_function *);
155
156int usb_function_deactivate(struct usb_function *);
157int usb_function_activate(struct usb_function *);
158
159int usb_interface_id(struct usb_configuration *, struct usb_function *);
160
161int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f,
162 struct usb_ep *_ep);
163
164#define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */
165
166/**
167 * struct usb_configuration - represents one gadget configuration
168 * @label: For diagnostics, describes the configuration.
169 * @strings: Tables of strings, keyed by identifiers assigned during @bind()
170 * and by language IDs provided in control requests.
171 * @descriptors: Table of descriptors preceding all function descriptors.
172 * Examples include OTG and vendor-specific descriptors.
173 * @unbind: Reverses @bind; called as a side effect of unregistering the
174 * driver which added this configuration.
175 * @setup: Used to delegate control requests that aren't handled by standard
176 * device infrastructure or directed at a specific interface.
177 * @bConfigurationValue: Copied into configuration descriptor.
178 * @iConfiguration: Copied into configuration descriptor.
179 * @bmAttributes: Copied into configuration descriptor.
180 * @bMaxPower: Copied into configuration descriptor.
181 * @cdev: assigned by @usb_add_config() before calling @bind(); this is
182 * the device associated with this configuration.
183 *
184 * Configurations are building blocks for gadget drivers structured around
185 * function drivers. Simple USB gadgets require only one function and one
186 * configuration, and handle dual-speed hardware by always providing the same
187 * functionality. Slightly more complex gadgets may have more than one
188 * single-function configuration at a given speed; or have configurations
189 * that only work at one speed.
190 *
191 * Composite devices are, by definition, ones with configurations which
192 * include more than one function.
193 *
194 * The lifecycle of a usb_configuration includes allocation, initialization
195 * of the fields described above, and calling @usb_add_config() to set up
196 * internal data and bind it to a specific device. The configuration's
197 * @bind() method is then used to initialize all the functions and then
198 * call @usb_add_function() for them.
199 *
200 * Those functions would normally be independent of each other, but that's
201 * not mandatory. CDC WMC devices are an example where functions often
202 * depend on other functions, with some functions subsidiary to others.
203 * Such interdependency may be managed in any way, so long as all of the
204 * descriptors complete by the time the composite driver returns from
205 * its bind() routine.
206 */
207struct usb_configuration {
208 const char *label;
209 struct usb_gadget_strings **strings;
210 const struct usb_descriptor_header **descriptors;
211
212 /* REVISIT: bind() functions can be marked __init, which
213 * makes trouble for section mismatch analysis. See if
214 * we can't restructure things to avoid mismatching...
215 */
216
217 /* configuration management: unbind/setup */
218 void (*unbind)(struct usb_configuration *);
219 int (*setup)(struct usb_configuration *,
220 const struct usb_ctrlrequest *);
221
222 /* fields in the config descriptor */
223 u8 bConfigurationValue;
224 u8 iConfiguration;
225 u8 bmAttributes;
226 u8 bMaxPower;
227
228 struct usb_composite_dev *cdev;
229
230 /* private: */
231 /* internals */
232 struct list_head list;
233 struct list_head functions;
234 u8 next_interface_id;
235 unsigned superspeed:1;
236 unsigned highspeed:1;
237 unsigned fullspeed:1;
238 struct usb_function *interface[MAX_CONFIG_INTERFACES];
239};
240
241int usb_add_config(struct usb_composite_dev *,
242 struct usb_configuration *,
243 int (*)(struct usb_configuration *));
244
245void usb_remove_config(struct usb_composite_dev *,
246 struct usb_configuration *);
247
248/**
249 * struct usb_composite_driver - groups configurations into a gadget
250 * @name: For diagnostics, identifies the driver.
251 * @iProduct: Used as iProduct override if @dev->iProduct is not set.
252 * If NULL value of @name is taken.
253 * @iManufacturer: Used as iManufacturer override if @dev->iManufacturer is
254 * not set. If NULL a default "<system> <release> with <udc>" value
255 * will be used.
256 * @iSerialNumber: Used as iSerialNumber override if @dev->iSerialNumber is
257 * not set.
258 * @dev: Template descriptor for the device, including default device
259 * identifiers.
260 * @strings: tables of strings, keyed by identifiers assigned during bind()
261 * and language IDs provided in control requests
262 * @max_speed: Highest speed the driver supports.
263 * @needs_serial: set to 1 if the gadget needs userspace to provide
264 * a serial number. If one is not provided, warning will be printed.
265 * @unbind: Reverses bind; called as a side effect of unregistering
266 * this driver.
267 * @disconnect: optional driver disconnect method
268 * @suspend: Notifies when the host stops sending USB traffic,
269 * after function notifications
270 * @resume: Notifies configuration when the host restarts USB traffic,
271 * before function notifications
272 *
273 * Devices default to reporting self powered operation. Devices which rely
274 * on bus powered operation should report this in their @bind() method.
275 *
276 * Before returning from bind, various fields in the template descriptor
277 * may be overridden. These include the idVendor/idProduct/bcdDevice values
278 * normally to bind the appropriate host side driver, and the three strings
279 * (iManufacturer, iProduct, iSerialNumber) normally used to provide user
280 * meaningful device identifiers. (The strings will not be defined unless
281 * they are defined in @dev and @strings.) The correct ep0 maxpacket size
282 * is also reported, as defined by the underlying controller driver.
283 */
284struct usb_composite_driver {
285 const char *name;
286 const char *iProduct;
287 const char *iManufacturer;
288 const char *iSerialNumber;
289 const struct usb_device_descriptor *dev;
290 struct usb_gadget_strings **strings;
291 enum usb_device_speed max_speed;
292 unsigned needs_serial:1;
293
294 int (*unbind)(struct usb_composite_dev *);
295
296 void (*disconnect)(struct usb_composite_dev *);
297
298 /* global suspend hooks */
299 void (*suspend)(struct usb_composite_dev *);
300 void (*resume)(struct usb_composite_dev *);
301};
302
303extern int usb_composite_probe(struct usb_composite_driver *driver,
304 int (*bind)(struct usb_composite_dev *cdev));
305extern void usb_composite_unregister(struct usb_composite_driver *driver);
306extern void usb_composite_setup_continue(struct usb_composite_dev *cdev);
307
308
309/**
310 * struct usb_composite_device - represents one composite usb gadget
311 * @gadget: read-only, abstracts the gadget's usb peripheral controller
312 * @req: used for control responses; buffer is pre-allocated
313 * @bufsiz: size of buffer pre-allocated in @req
314 * @config: the currently active configuration
315 *
316 * One of these devices is allocated and initialized before the
317 * associated device driver's bind() is called.
318 *
319 * OPEN ISSUE: it appears that some WUSB devices will need to be
320 * built by combining a normal (wired) gadget with a wireless one.
321 * This revision of the gadget framework should probably try to make
322 * sure doing that won't hurt too much.
323 *
324 * One notion for how to handle Wireless USB devices involves:
325 * (a) a second gadget here, discovery mechanism TBD, but likely
326 * needing separate "register/unregister WUSB gadget" calls;
327 * (b) updates to usb_gadget to include flags "is it wireless",
328 * "is it wired", plus (presumably in a wrapper structure)
329 * bandgroup and PHY info;
330 * (c) presumably a wireless_ep wrapping a usb_ep, and reporting
331 * wireless-specific parameters like maxburst and maxsequence;
332 * (d) configurations that are specific to wireless links;
333 * (e) function drivers that understand wireless configs and will
334 * support wireless for (additional) function instances;
335 * (f) a function to support association setup (like CBAF), not
336 * necessarily requiring a wireless adapter;
337 * (g) composite device setup that can create one or more wireless
338 * configs, including appropriate association setup support;
339 * (h) more, TBD.
340 */
341struct usb_composite_dev {
342 struct usb_gadget *gadget;
343 struct usb_request *req;
344 unsigned bufsiz;
345
346 struct usb_configuration *config;
347
348 /* private: */
349 /* internals */
350 unsigned int suspended:1;
351 struct usb_device_descriptor desc;
352 struct list_head configs;
353 struct usb_composite_driver *driver;
354 u8 next_string_id;
355 u8 manufacturer_override;
356 u8 product_override;
357 u8 serial_override;
358
359 /* the gadget driver won't enable the data pullup
360 * while the deactivation count is nonzero.
361 */
362 unsigned deactivations;
363
364 /* the composite driver won't complete the control transfer's
365 * data/status stages till delayed_status is zero.
366 */
367 int delayed_status;
368
369 /* protects deactivations and delayed_status counts*/
370 spinlock_t lock;
371};
372
373extern int usb_string_id(struct usb_composite_dev *c);
374extern int usb_string_ids_tab(struct usb_composite_dev *c,
375 struct usb_string *str);
376extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n);
377
378
379/* messaging utils */
380#define DBG(d, fmt, args...) \
381 dev_dbg(&(d)->gadget->dev , fmt , ## args)
382#define VDBG(d, fmt, args...) \
383 dev_vdbg(&(d)->gadget->dev , fmt , ## args)
384#define ERROR(d, fmt, args...) \
385 dev_err(&(d)->gadget->dev , fmt , ## args)
386#define WARNING(d, fmt, args...) \
387 dev_warn(&(d)->gadget->dev , fmt , ## args)
388#define INFO(d, fmt, args...) \
389 dev_info(&(d)->gadget->dev , fmt , ## args)
390
391#endif /* __LINUX_USB_COMPOSITE_H */