2 * composite.h -- framework for usb gadgets which are composite devices
4 * Copyright (C) 2006-2008 David Brownell
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.
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.
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
21 #ifndef __LINUX_USB_COMPOSITE_H
22 #define __LINUX_USB_COMPOSITE_H
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.
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.
37 #include <linux/bcd.h>
38 #include <linux/version.h>
39 #include <linux/usb/ch9.h>
40 #include <linux/usb/gadget.h>
41 #include <linux/log2.h>
42 #include <linux/configfs.h>
45 * USB function drivers should return USB_GADGET_DELAYED_STATUS if they
46 * wish to delay the data/status stages of the control transfer till they
47 * are ready. The control transfer will then be kept from completing till
48 * all the function drivers that requested for USB_GADGET_DELAYED_STAUS
49 * invoke usb_composite_setup_continue().
51 #define USB_GADGET_DELAYED_STATUS 0x7fff /* Impossibly large value */
53 /* big enough to hold our biggest descriptor */
54 #define USB_COMP_EP0_BUFSIZ 1024
56 /* OS feature descriptor length <= 4kB */
57 #define USB_COMP_EP0_OS_DESC_BUFSIZ 4096
59 #define USB_MS_TO_HS_INTERVAL(x) (ilog2((x * 1000 / 125)) + 1)
60 struct usb_configuration;
63 * struct usb_os_desc_ext_prop - describes one "Extended Property"
64 * @entry: used to keep a list of extended properties
65 * @type: Extended Property type
66 * @name_len: Extended Property unicode name length, including terminating '\0'
67 * @name: Extended Property name
68 * @data_len: Length of Extended Property blob (for unicode store double len)
69 * @data: Extended Property blob
70 * @item: Represents this Extended Property in configfs
72 struct usb_os_desc_ext_prop {
73 struct list_head entry;
79 struct config_item item;
83 * struct usb_os_desc - describes OS descriptors associated with one interface
84 * @ext_compat_id: 16 bytes of "Compatible ID" and "Subcompatible ID"
85 * @ext_prop: Extended Properties list
86 * @ext_prop_len: Total length of Extended Properties blobs
87 * @ext_prop_count: Number of Extended Properties
88 * @opts_mutex: Optional mutex protecting config data of a usb_function_instance
89 * @group: Represents OS descriptors associated with an interface in configfs
90 * @owner: Module associated with this OS descriptor
94 struct list_head ext_prop;
97 struct mutex *opts_mutex;
98 struct config_group group;
103 * struct usb_os_desc_table - describes OS descriptors associated with one
104 * interface of a usb_function
105 * @if_id: Interface id
106 * @os_desc: "Extended Compatibility ID" and "Extended Properties" of the
109 * Each interface can have at most one "Extended Compatibility ID" and a
110 * number of "Extended Properties".
112 struct usb_os_desc_table {
114 struct usb_os_desc *os_desc;
118 * struct usb_function - describes one function of a configuration
119 * @name: For diagnostics, identifies the function.
120 * @strings: tables of strings, keyed by identifiers assigned during bind()
121 * and by language IDs provided in control requests
122 * @fs_descriptors: Table of full (or low) speed descriptors, using interface and
123 * string identifiers assigned during @bind(). If this pointer is null,
124 * the function will not be available at full speed (or at low speed).
125 * @hs_descriptors: Table of high speed descriptors, using interface and
126 * string identifiers assigned during @bind(). If this pointer is null,
127 * the function will not be available at high speed.
128 * @ss_descriptors: Table of super speed descriptors, using interface and
129 * string identifiers assigned during @bind(). If this
130 * pointer is null after initiation, the function will not
131 * be available at super speed.
132 * @config: assigned when @usb_add_function() is called; this is the
133 * configuration with which this function is associated.
134 * @os_desc_table: Table of (interface id, os descriptors) pairs. The function
135 * can expose more than one interface. If an interface is a member of
136 * an IAD, only the first interface of IAD has its entry in the table.
137 * @os_desc_n: Number of entries in os_desc_table
138 * @bind: Before the gadget can register, all of its functions bind() to the
139 * available resources including string and interface identifiers used
140 * in interface or class descriptors; endpoints; I/O buffers; and so on.
141 * @unbind: Reverses @bind; called as a side effect of unregistering the
142 * driver which added this function.
143 * @free_func: free the struct usb_function.
144 * @mod: (internal) points to the module that created this structure.
145 * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may
146 * initialize usb_ep.driver data at this time (when it is used).
147 * Note that setting an interface to its current altsetting resets
148 * interface state, and that all interfaces have a disabled state.
149 * @get_alt: Returns the active altsetting. If this is not provided,
150 * then only altsetting zero is supported.
151 * @disable: (REQUIRED) Indicates the function should be disabled. Reasons
152 * include host resetting or reconfiguring the gadget, and disconnection.
153 * @setup: Used for interface-specific control requests.
154 * @req_match: Tests if a given class request can be handled by this function.
155 * @suspend: Notifies functions when the host stops sending USB traffic.
156 * @resume: Notifies functions when the host restarts USB traffic.
157 * @get_status: Returns function status as a reply to
158 * GetStatus() request when the recipient is Interface.
159 * @func_suspend: callback to be called when
160 * SetFeature(FUNCTION_SUSPEND) is reseived
162 * A single USB function uses one or more interfaces, and should in most
163 * cases support operation at both full and high speeds. Each function is
164 * associated by @usb_add_function() with a one configuration; that function
165 * causes @bind() to be called so resources can be allocated as part of
166 * setting up a gadget driver. Those resources include endpoints, which
167 * should be allocated using @usb_ep_autoconfig().
169 * To support dual speed operation, a function driver provides descriptors
170 * for both high and full speed operation. Except in rare cases that don't
171 * involve bulk endpoints, each speed needs different endpoint descriptors.
173 * Function drivers choose their own strategies for managing instance data.
174 * The simplest strategy just declares it "static', which means the function
175 * can only be activated once. If the function needs to be exposed in more
176 * than one configuration at a given speed, it needs to support multiple
177 * usb_function structures (one for each configuration).
179 * A more complex strategy might encapsulate a @usb_function structure inside
180 * a driver-specific instance structure to allows multiple activations. An
181 * example of multiple activations might be a CDC ACM function that supports
182 * two or more distinct instances within the same configuration, providing
183 * several independent logical data links to a USB host.
186 struct usb_function {
188 struct usb_gadget_strings **strings;
189 struct usb_descriptor_header **fs_descriptors;
190 struct usb_descriptor_header **hs_descriptors;
191 struct usb_descriptor_header **ss_descriptors;
193 struct usb_configuration *config;
195 struct usb_os_desc_table *os_desc_table;
198 /* REVISIT: bind() functions can be marked __init, which
199 * makes trouble for section mismatch analysis. See if
200 * we can't restructure things to avoid mismatching.
201 * Related: unbind() may kfree() but bind() won't...
204 /* configuration management: bind/unbind */
205 int (*bind)(struct usb_configuration *,
206 struct usb_function *);
207 void (*unbind)(struct usb_configuration *,
208 struct usb_function *);
209 void (*free_func)(struct usb_function *f);
212 /* runtime state management */
213 int (*set_alt)(struct usb_function *,
214 unsigned interface, unsigned alt);
215 int (*get_alt)(struct usb_function *,
217 void (*disable)(struct usb_function *);
218 int (*setup)(struct usb_function *,
219 const struct usb_ctrlrequest *);
220 bool (*req_match)(struct usb_function *,
221 const struct usb_ctrlrequest *);
222 void (*suspend)(struct usb_function *);
223 void (*resume)(struct usb_function *);
225 /* USB 3.0 additions */
226 int (*get_status)(struct usb_function *);
227 int (*func_suspend)(struct usb_function *,
231 struct list_head list;
232 DECLARE_BITMAP(endpoints, 32);
233 const struct usb_function_instance *fi;
235 unsigned int bind_deactivated:1;
238 int usb_add_function(struct usb_configuration *, struct usb_function *);
240 int usb_function_deactivate(struct usb_function *);
241 int usb_function_activate(struct usb_function *);
243 int usb_interface_id(struct usb_configuration *, struct usb_function *);
245 int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f,
248 #define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */
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.
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.
276 * Composite devices are, by definition, ones with configurations which
277 * include more than one function.
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.
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.
292 struct usb_configuration {
294 struct usb_gadget_strings **strings;
295 const struct usb_descriptor_header **descriptors;
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...
302 /* configuration management: unbind/setup */
303 void (*unbind)(struct usb_configuration *);
304 int (*setup)(struct usb_configuration *,
305 const struct usb_ctrlrequest *);
307 /* fields in the config descriptor */
308 u8 bConfigurationValue;
313 struct usb_composite_dev *cdev;
317 struct list_head list;
318 struct list_head functions;
319 u8 next_interface_id;
320 unsigned superspeed:1;
321 unsigned highspeed:1;
322 unsigned fullspeed:1;
323 struct usb_function *interface[MAX_CONFIG_INTERFACES];
326 int usb_add_config(struct usb_composite_dev *,
327 struct usb_configuration *,
328 int (*)(struct usb_configuration *));
330 void usb_remove_config(struct usb_composite_dev *,
331 struct usb_configuration *);
333 /* predefined index for usb_composite_driver */
335 USB_GADGET_MANUFACTURER_IDX = 0,
336 USB_GADGET_PRODUCT_IDX,
337 USB_GADGET_SERIAL_IDX,
338 USB_GADGET_FIRST_AVAIL_IDX,
342 * struct usb_composite_driver - groups configurations into a gadget
343 * @name: For diagnostics, identifies the driver.
344 * @dev: Template descriptor for the device, including default device
346 * @strings: tables of strings, keyed by identifiers assigned during @bind
347 * and language IDs provided in control requests. Note: The first entries
348 * are predefined. The first entry that may be used is
349 * USB_GADGET_FIRST_AVAIL_IDX
350 * @max_speed: Highest speed the driver supports.
351 * @needs_serial: set to 1 if the gadget needs userspace to provide
352 * a serial number. If one is not provided, warning will be printed.
353 * @bind: (REQUIRED) Used to allocate resources that are shared across the
354 * whole device, such as string IDs, and add its configurations using
355 * @usb_add_config(). This may fail by returning a negative errno
356 * value; it should return zero on successful initialization.
357 * @unbind: Reverses @bind; called as a side effect of unregistering
359 * @disconnect: optional driver disconnect method
360 * @suspend: Notifies when the host stops sending USB traffic,
361 * after function notifications
362 * @resume: Notifies configuration when the host restarts USB traffic,
363 * before function notifications
364 * @gadget_driver: Gadget driver controlling this driver
366 * Devices default to reporting self powered operation. Devices which rely
367 * on bus powered operation should report this in their @bind method.
369 * Before returning from @bind, various fields in the template descriptor
370 * may be overridden. These include the idVendor/idProduct/bcdDevice values
371 * normally to bind the appropriate host side driver, and the three strings
372 * (iManufacturer, iProduct, iSerialNumber) normally used to provide user
373 * meaningful device identifiers. (The strings will not be defined unless
374 * they are defined in @dev and @strings.) The correct ep0 maxpacket size
375 * is also reported, as defined by the underlying controller driver.
377 struct usb_composite_driver {
379 const struct usb_device_descriptor *dev;
380 struct usb_gadget_strings **strings;
381 enum usb_device_speed max_speed;
382 unsigned needs_serial:1;
384 int (*bind)(struct usb_composite_dev *cdev);
385 int (*unbind)(struct usb_composite_dev *);
387 void (*disconnect)(struct usb_composite_dev *);
389 /* global suspend hooks */
390 void (*suspend)(struct usb_composite_dev *);
391 void (*resume)(struct usb_composite_dev *);
392 struct usb_gadget_driver gadget_driver;
395 extern int usb_composite_probe(struct usb_composite_driver *driver);
396 extern void usb_composite_unregister(struct usb_composite_driver *driver);
399 * module_usb_composite_driver() - Helper macro for registering a USB gadget
401 * @__usb_composite_driver: usb_composite_driver struct
403 * Helper macro for USB gadget composite drivers which do not do anything
404 * special in module init/exit. This eliminates a lot of boilerplate. Each
405 * module may only use this macro once, and calling it replaces module_init()
408 #define module_usb_composite_driver(__usb_composite_driver) \
409 module_driver(__usb_composite_driver, usb_composite_probe, \
410 usb_composite_unregister)
412 extern void usb_composite_setup_continue(struct usb_composite_dev *cdev);
413 extern int composite_dev_prepare(struct usb_composite_driver *composite,
414 struct usb_composite_dev *cdev);
415 extern int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
417 void composite_dev_cleanup(struct usb_composite_dev *cdev);
419 static inline struct usb_composite_driver *to_cdriver(
420 struct usb_gadget_driver *gdrv)
422 return container_of(gdrv, struct usb_composite_driver, gadget_driver);
425 #define OS_STRING_QW_SIGN_LEN 14
426 #define OS_STRING_IDX 0xEE
429 * struct usb_composite_device - represents one composite usb gadget
430 * @gadget: read-only, abstracts the gadget's usb peripheral controller
431 * @req: used for control responses; buffer is pre-allocated
432 * @os_desc_req: used for OS descriptors responses; buffer is pre-allocated
433 * @config: the currently active configuration
434 * @qw_sign: qwSignature part of the OS string
435 * @b_vendor_code: bMS_VendorCode part of the OS string
436 * @use_os_string: false by default, interested gadgets set it
437 * @os_desc_config: the configuration to be used with OS descriptors
438 * @setup_pending: true when setup request is queued but not completed
439 * @os_desc_pending: true when os_desc request is queued but not completed
441 * One of these devices is allocated and initialized before the
442 * associated device driver's bind() is called.
444 * OPEN ISSUE: it appears that some WUSB devices will need to be
445 * built by combining a normal (wired) gadget with a wireless one.
446 * This revision of the gadget framework should probably try to make
447 * sure doing that won't hurt too much.
449 * One notion for how to handle Wireless USB devices involves:
450 * (a) a second gadget here, discovery mechanism TBD, but likely
451 * needing separate "register/unregister WUSB gadget" calls;
452 * (b) updates to usb_gadget to include flags "is it wireless",
453 * "is it wired", plus (presumably in a wrapper structure)
454 * bandgroup and PHY info;
455 * (c) presumably a wireless_ep wrapping a usb_ep, and reporting
456 * wireless-specific parameters like maxburst and maxsequence;
457 * (d) configurations that are specific to wireless links;
458 * (e) function drivers that understand wireless configs and will
459 * support wireless for (additional) function instances;
460 * (f) a function to support association setup (like CBAF), not
461 * necessarily requiring a wireless adapter;
462 * (g) composite device setup that can create one or more wireless
463 * configs, including appropriate association setup support;
466 struct usb_composite_dev {
467 struct usb_gadget *gadget;
468 struct usb_request *req;
469 struct usb_request *os_desc_req;
471 struct usb_configuration *config;
473 /* OS String is a custom (yet popular) extension to the USB standard. */
474 u8 qw_sign[OS_STRING_QW_SIGN_LEN];
476 struct usb_configuration *os_desc_config;
477 unsigned int use_os_string:1;
481 unsigned int suspended:1;
482 struct usb_device_descriptor desc;
483 struct list_head configs;
484 struct list_head gstrings;
485 struct usb_composite_driver *driver;
487 char *def_manufacturer;
489 /* the gadget driver won't enable the data pullup
490 * while the deactivation count is nonzero.
492 unsigned deactivations;
494 /* the composite driver won't complete the control transfer's
495 * data/status stages till delayed_status is zero.
499 /* protects deactivations and delayed_status counts*/
502 unsigned setup_pending:1;
503 unsigned os_desc_pending:1;
506 extern int usb_string_id(struct usb_composite_dev *c);
507 extern int usb_string_ids_tab(struct usb_composite_dev *c,
508 struct usb_string *str);
509 extern struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
510 struct usb_gadget_strings **sp, unsigned n_strings);
512 extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n);
514 extern void composite_disconnect(struct usb_gadget *gadget);
515 extern int composite_setup(struct usb_gadget *gadget,
516 const struct usb_ctrlrequest *ctrl);
517 extern void composite_suspend(struct usb_gadget *gadget);
518 extern void composite_resume(struct usb_gadget *gadget);
521 * Some systems will need runtime overrides for the product identifiers
522 * published in the device descriptor, either numbers or strings or both.
523 * String parameters are in UTF-8 (superset of ASCII's 7 bit characters).
525 struct usb_composite_overwrite {
533 #define USB_GADGET_COMPOSITE_OPTIONS() \
534 static struct usb_composite_overwrite coverwrite; \
536 module_param_named(idVendor, coverwrite.idVendor, ushort, S_IRUGO); \
537 MODULE_PARM_DESC(idVendor, "USB Vendor ID"); \
539 module_param_named(idProduct, coverwrite.idProduct, ushort, S_IRUGO); \
540 MODULE_PARM_DESC(idProduct, "USB Product ID"); \
542 module_param_named(bcdDevice, coverwrite.bcdDevice, ushort, S_IRUGO); \
543 MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)"); \
545 module_param_named(iSerialNumber, coverwrite.serial_number, charp, \
547 MODULE_PARM_DESC(iSerialNumber, "SerialNumber string"); \
549 module_param_named(iManufacturer, coverwrite.manufacturer, charp, \
551 MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string"); \
553 module_param_named(iProduct, coverwrite.product, charp, S_IRUGO); \
554 MODULE_PARM_DESC(iProduct, "USB Product string")
556 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
557 struct usb_composite_overwrite *covr);
559 static inline u16 get_default_bcdDevice(void)
563 bcdDevice = bin2bcd((LINUX_VERSION_CODE >> 16 & 0xff)) << 8;
564 bcdDevice |= bin2bcd((LINUX_VERSION_CODE >> 8 & 0xff));
568 struct usb_function_driver {
571 struct list_head list;
572 struct usb_function_instance *(*alloc_inst)(void);
573 struct usb_function *(*alloc_func)(struct usb_function_instance *inst);
576 struct usb_function_instance {
577 struct config_group group;
578 struct list_head cfs_list;
579 struct usb_function_driver *fd;
580 int (*set_inst_name)(struct usb_function_instance *inst,
582 void (*free_func_inst)(struct usb_function_instance *inst);
585 void usb_function_unregister(struct usb_function_driver *f);
586 int usb_function_register(struct usb_function_driver *newf);
587 void usb_put_function_instance(struct usb_function_instance *fi);
588 void usb_put_function(struct usb_function *f);
589 struct usb_function_instance *usb_get_function_instance(const char *name);
590 struct usb_function *usb_get_function(struct usb_function_instance *fi);
592 struct usb_configuration *usb_get_config(struct usb_composite_dev *cdev,
594 int usb_add_config_only(struct usb_composite_dev *cdev,
595 struct usb_configuration *config);
596 void usb_remove_function(struct usb_configuration *c, struct usb_function *f);
598 #define DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \
599 static struct usb_function_driver _name ## usb_func = { \
600 .name = __stringify(_name), \
601 .mod = THIS_MODULE, \
602 .alloc_inst = _inst_alloc, \
603 .alloc_func = _func_alloc, \
605 MODULE_ALIAS("usbfunc:"__stringify(_name));
607 #define DECLARE_USB_FUNCTION_INIT(_name, _inst_alloc, _func_alloc) \
608 DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \
609 static int __init _name ## mod_init(void) \
611 return usb_function_register(&_name ## usb_func); \
613 static void __exit _name ## mod_exit(void) \
615 usb_function_unregister(&_name ## usb_func); \
617 module_init(_name ## mod_init); \
618 module_exit(_name ## mod_exit)
620 /* messaging utils */
621 #define DBG(d, fmt, args...) \
622 dev_dbg(&(d)->gadget->dev , fmt , ## args)
623 #define VDBG(d, fmt, args...) \
624 dev_vdbg(&(d)->gadget->dev , fmt , ## args)
625 #define ERROR(d, fmt, args...) \
626 dev_err(&(d)->gadget->dev , fmt , ## args)
627 #define WARNING(d, fmt, args...) \
628 dev_warn(&(d)->gadget->dev , fmt , ## args)
629 #define INFO(d, fmt, args...) \
630 dev_info(&(d)->gadget->dev , fmt , ## args)
632 #endif /* __LINUX_USB_COMPOSITE_H */