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 #define USB_MS_TO_HS_INTERVAL(x) (ilog2((x * 1000 / 125)) + 1)
57 struct usb_configuration
;
60 * struct usb_os_desc_ext_prop - describes one "Extended Property"
61 * @entry: used to keep a list of extended properties
62 * @type: Extended Property type
63 * @name_len: Extended Property unicode name length, including terminating '\0'
64 * @name: Extended Property name
65 * @data_len: Length of Extended Property blob (for unicode store double len)
66 * @data: Extended Property blob
67 * @item: Represents this Extended Property in configfs
69 struct usb_os_desc_ext_prop
{
70 struct list_head entry
;
76 struct config_item item
;
80 * struct usb_os_desc - describes OS descriptors associated with one interface
81 * @ext_compat_id: 16 bytes of "Compatible ID" and "Subcompatible ID"
82 * @ext_prop: Extended Properties list
83 * @ext_prop_len: Total length of Extended Properties blobs
84 * @ext_prop_count: Number of Extended Properties
85 * @opts_mutex: Optional mutex protecting config data of a usb_function_instance
86 * @group: Represents OS descriptors associated with an interface in configfs
87 * @owner: Module associated with this OS descriptor
91 struct list_head ext_prop
;
94 struct mutex
*opts_mutex
;
95 struct config_group group
;
100 * struct usb_os_desc_table - describes OS descriptors associated with one
101 * interface of a usb_function
102 * @if_id: Interface id
103 * @os_desc: "Extended Compatibility ID" and "Extended Properties" of the
106 * Each interface can have at most one "Extended Compatibility ID" and a
107 * number of "Extended Properties".
109 struct usb_os_desc_table
{
111 struct usb_os_desc
*os_desc
;
115 * struct usb_function - describes one function of a configuration
116 * @name: For diagnostics, identifies the function.
117 * @strings: tables of strings, keyed by identifiers assigned during bind()
118 * and by language IDs provided in control requests
119 * @fs_descriptors: Table of full (or low) speed descriptors, using interface and
120 * string identifiers assigned during @bind(). If this pointer is null,
121 * the function will not be available at full speed (or at low speed).
122 * @hs_descriptors: Table of high speed descriptors, using interface and
123 * string identifiers assigned during @bind(). If this pointer is null,
124 * the function will not be available at high speed.
125 * @ss_descriptors: Table of super speed descriptors, using interface and
126 * string identifiers assigned during @bind(). If this
127 * pointer is null after initiation, the function will not
128 * be available at super speed.
129 * @ssp_descriptors: Table of super speed plus descriptors, using
130 * interface and string identifiers assigned during @bind(). If
131 * this pointer is null after initiation, the function will not
132 * be available at super speed plus.
133 * @config: assigned when @usb_add_function() is called; this is the
134 * configuration with which this function is associated.
135 * @os_desc_table: Table of (interface id, os descriptors) pairs. The function
136 * can expose more than one interface. If an interface is a member of
137 * an IAD, only the first interface of IAD has its entry in the table.
138 * @os_desc_n: Number of entries in os_desc_table
139 * @bind: Before the gadget can register, all of its functions bind() to the
140 * available resources including string and interface identifiers used
141 * in interface or class descriptors; endpoints; I/O buffers; and so on.
142 * @unbind: Reverses @bind; called as a side effect of unregistering the
143 * driver which added this function.
144 * @free_func: free the struct usb_function.
145 * @mod: (internal) points to the module that created this structure.
146 * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may
147 * initialize usb_ep.driver data at this time (when it is used).
148 * Note that setting an interface to its current altsetting resets
149 * interface state, and that all interfaces have a disabled state.
150 * @get_alt: Returns the active altsetting. If this is not provided,
151 * then only altsetting zero is supported.
152 * @disable: (REQUIRED) Indicates the function should be disabled. Reasons
153 * include host resetting or reconfiguring the gadget, and disconnection.
154 * @setup: Used for interface-specific control requests.
155 * @req_match: Tests if a given class request can be handled by this function.
156 * @suspend: Notifies functions when the host stops sending USB traffic.
157 * @resume: Notifies functions when the host restarts USB traffic.
158 * @get_status: Returns function status as a reply to
159 * GetStatus() request when the recipient is Interface.
160 * @func_suspend: callback to be called when
161 * SetFeature(FUNCTION_SUSPEND) is reseived
163 * A single USB function uses one or more interfaces, and should in most
164 * cases support operation at both full and high speeds. Each function is
165 * associated by @usb_add_function() with a one configuration; that function
166 * causes @bind() to be called so resources can be allocated as part of
167 * setting up a gadget driver. Those resources include endpoints, which
168 * should be allocated using @usb_ep_autoconfig().
170 * To support dual speed operation, a function driver provides descriptors
171 * for both high and full speed operation. Except in rare cases that don't
172 * involve bulk endpoints, each speed needs different endpoint descriptors.
174 * Function drivers choose their own strategies for managing instance data.
175 * The simplest strategy just declares it "static', which means the function
176 * can only be activated once. If the function needs to be exposed in more
177 * than one configuration at a given speed, it needs to support multiple
178 * usb_function structures (one for each configuration).
180 * A more complex strategy might encapsulate a @usb_function structure inside
181 * a driver-specific instance structure to allows multiple activations. An
182 * example of multiple activations might be a CDC ACM function that supports
183 * two or more distinct instances within the same configuration, providing
184 * several independent logical data links to a USB host.
187 struct usb_function
{
189 struct usb_gadget_strings
**strings
;
190 struct usb_descriptor_header
**fs_descriptors
;
191 struct usb_descriptor_header
**hs_descriptors
;
192 struct usb_descriptor_header
**ss_descriptors
;
193 struct usb_descriptor_header
**ssp_descriptors
;
195 struct usb_configuration
*config
;
197 struct usb_os_desc_table
*os_desc_table
;
200 /* REVISIT: bind() functions can be marked __init, which
201 * makes trouble for section mismatch analysis. See if
202 * we can't restructure things to avoid mismatching.
203 * Related: unbind() may kfree() but bind() won't...
206 /* configuration management: bind/unbind */
207 int (*bind
)(struct usb_configuration
*,
208 struct usb_function
*);
209 void (*unbind
)(struct usb_configuration
*,
210 struct usb_function
*);
211 void (*free_func
)(struct usb_function
*f
);
214 /* runtime state management */
215 int (*set_alt
)(struct usb_function
*,
216 unsigned interface
, unsigned alt
);
217 int (*get_alt
)(struct usb_function
*,
219 void (*disable
)(struct usb_function
*);
220 int (*setup
)(struct usb_function
*,
221 const struct usb_ctrlrequest
*);
222 bool (*req_match
)(struct usb_function
*,
223 const struct usb_ctrlrequest
*,
225 void (*suspend
)(struct usb_function
*);
226 void (*resume
)(struct usb_function
*);
228 /* USB 3.0 additions */
229 int (*get_status
)(struct usb_function
*);
230 int (*func_suspend
)(struct usb_function
*,
234 struct list_head list
;
235 DECLARE_BITMAP(endpoints
, 32);
236 const struct usb_function_instance
*fi
;
238 unsigned int bind_deactivated
:1;
241 int usb_add_function(struct usb_configuration
*, struct usb_function
*);
243 int usb_function_deactivate(struct usb_function
*);
244 int usb_function_activate(struct usb_function
*);
246 int usb_interface_id(struct usb_configuration
*, struct usb_function
*);
248 int config_ep_by_speed(struct usb_gadget
*g
, struct usb_function
*f
,
251 #define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */
254 * struct usb_configuration - represents one gadget configuration
255 * @label: For diagnostics, describes the configuration.
256 * @strings: Tables of strings, keyed by identifiers assigned during @bind()
257 * and by language IDs provided in control requests.
258 * @descriptors: Table of descriptors preceding all function descriptors.
259 * Examples include OTG and vendor-specific descriptors.
260 * @unbind: Reverses @bind; called as a side effect of unregistering the
261 * driver which added this configuration.
262 * @setup: Used to delegate control requests that aren't handled by standard
263 * device infrastructure or directed at a specific interface.
264 * @bConfigurationValue: Copied into configuration descriptor.
265 * @iConfiguration: Copied into configuration descriptor.
266 * @bmAttributes: Copied into configuration descriptor.
267 * @MaxPower: Power consumtion in mA. Used to compute bMaxPower in the
268 * configuration descriptor after considering the bus speed.
269 * @cdev: assigned by @usb_add_config() before calling @bind(); this is
270 * the device associated with this configuration.
272 * Configurations are building blocks for gadget drivers structured around
273 * function drivers. Simple USB gadgets require only one function and one
274 * configuration, and handle dual-speed hardware by always providing the same
275 * functionality. Slightly more complex gadgets may have more than one
276 * single-function configuration at a given speed; or have configurations
277 * that only work at one speed.
279 * Composite devices are, by definition, ones with configurations which
280 * include more than one function.
282 * The lifecycle of a usb_configuration includes allocation, initialization
283 * of the fields described above, and calling @usb_add_config() to set up
284 * internal data and bind it to a specific device. The configuration's
285 * @bind() method is then used to initialize all the functions and then
286 * call @usb_add_function() for them.
288 * Those functions would normally be independent of each other, but that's
289 * not mandatory. CDC WMC devices are an example where functions often
290 * depend on other functions, with some functions subsidiary to others.
291 * Such interdependency may be managed in any way, so long as all of the
292 * descriptors complete by the time the composite driver returns from
293 * its bind() routine.
295 struct usb_configuration
{
297 struct usb_gadget_strings
**strings
;
298 const struct usb_descriptor_header
**descriptors
;
300 /* REVISIT: bind() functions can be marked __init, which
301 * makes trouble for section mismatch analysis. See if
302 * we can't restructure things to avoid mismatching...
305 /* configuration management: unbind/setup */
306 void (*unbind
)(struct usb_configuration
*);
307 int (*setup
)(struct usb_configuration
*,
308 const struct usb_ctrlrequest
*);
310 /* fields in the config descriptor */
311 u8 bConfigurationValue
;
316 struct usb_composite_dev
*cdev
;
320 struct list_head list
;
321 struct list_head functions
;
322 u8 next_interface_id
;
323 unsigned superspeed
:1;
324 unsigned highspeed
:1;
325 unsigned fullspeed
:1;
326 unsigned superspeed_plus
:1;
327 struct usb_function
*interface
[MAX_CONFIG_INTERFACES
];
330 int usb_add_config(struct usb_composite_dev
*,
331 struct usb_configuration
*,
332 int (*)(struct usb_configuration
*));
334 void usb_remove_config(struct usb_composite_dev
*,
335 struct usb_configuration
*);
337 /* predefined index for usb_composite_driver */
339 USB_GADGET_MANUFACTURER_IDX
= 0,
340 USB_GADGET_PRODUCT_IDX
,
341 USB_GADGET_SERIAL_IDX
,
342 USB_GADGET_FIRST_AVAIL_IDX
,
346 * struct usb_composite_driver - groups configurations into a gadget
347 * @name: For diagnostics, identifies the driver.
348 * @dev: Template descriptor for the device, including default device
350 * @strings: tables of strings, keyed by identifiers assigned during @bind
351 * and language IDs provided in control requests. Note: The first entries
352 * are predefined. The first entry that may be used is
353 * USB_GADGET_FIRST_AVAIL_IDX
354 * @max_speed: Highest speed the driver supports.
355 * @needs_serial: set to 1 if the gadget needs userspace to provide
356 * a serial number. If one is not provided, warning will be printed.
357 * @bind: (REQUIRED) Used to allocate resources that are shared across the
358 * whole device, such as string IDs, and add its configurations using
359 * @usb_add_config(). This may fail by returning a negative errno
360 * value; it should return zero on successful initialization.
361 * @unbind: Reverses @bind; called as a side effect of unregistering
363 * @disconnect: optional driver disconnect method
364 * @suspend: Notifies when the host stops sending USB traffic,
365 * after function notifications
366 * @resume: Notifies configuration when the host restarts USB traffic,
367 * before function notifications
368 * @gadget_driver: Gadget driver controlling this driver
370 * Devices default to reporting self powered operation. Devices which rely
371 * on bus powered operation should report this in their @bind method.
373 * Before returning from @bind, various fields in the template descriptor
374 * may be overridden. These include the idVendor/idProduct/bcdDevice values
375 * normally to bind the appropriate host side driver, and the three strings
376 * (iManufacturer, iProduct, iSerialNumber) normally used to provide user
377 * meaningful device identifiers. (The strings will not be defined unless
378 * they are defined in @dev and @strings.) The correct ep0 maxpacket size
379 * is also reported, as defined by the underlying controller driver.
381 struct usb_composite_driver
{
383 const struct usb_device_descriptor
*dev
;
384 struct usb_gadget_strings
**strings
;
385 enum usb_device_speed max_speed
;
386 unsigned needs_serial
:1;
388 int (*bind
)(struct usb_composite_dev
*cdev
);
389 int (*unbind
)(struct usb_composite_dev
*);
391 void (*disconnect
)(struct usb_composite_dev
*);
393 /* global suspend hooks */
394 void (*suspend
)(struct usb_composite_dev
*);
395 void (*resume
)(struct usb_composite_dev
*);
396 struct usb_gadget_driver gadget_driver
;
399 extern int usb_composite_probe(struct usb_composite_driver
*driver
);
400 extern void usb_composite_unregister(struct usb_composite_driver
*driver
);
403 * module_usb_composite_driver() - Helper macro for registering a USB gadget
405 * @__usb_composite_driver: usb_composite_driver struct
407 * Helper macro for USB gadget composite drivers which do not do anything
408 * special in module init/exit. This eliminates a lot of boilerplate. Each
409 * module may only use this macro once, and calling it replaces module_init()
412 #define module_usb_composite_driver(__usb_composite_driver) \
413 module_driver(__usb_composite_driver, usb_composite_probe, \
414 usb_composite_unregister)
416 extern void usb_composite_setup_continue(struct usb_composite_dev
*cdev
);
417 extern int composite_dev_prepare(struct usb_composite_driver
*composite
,
418 struct usb_composite_dev
*cdev
);
419 extern int composite_os_desc_req_prepare(struct usb_composite_dev
*cdev
,
421 void composite_dev_cleanup(struct usb_composite_dev
*cdev
);
423 static inline struct usb_composite_driver
*to_cdriver(
424 struct usb_gadget_driver
*gdrv
)
426 return container_of(gdrv
, struct usb_composite_driver
, gadget_driver
);
429 #define OS_STRING_QW_SIGN_LEN 14
430 #define OS_STRING_IDX 0xEE
433 * struct usb_composite_device - represents one composite usb gadget
434 * @gadget: read-only, abstracts the gadget's usb peripheral controller
435 * @req: used for control responses; buffer is pre-allocated
436 * @os_desc_req: used for OS descriptors responses; buffer is pre-allocated
437 * @config: the currently active configuration
438 * @qw_sign: qwSignature part of the OS string
439 * @b_vendor_code: bMS_VendorCode part of the OS string
440 * @use_os_string: false by default, interested gadgets set it
441 * @os_desc_config: the configuration to be used with OS descriptors
442 * @setup_pending: true when setup request is queued but not completed
443 * @os_desc_pending: true when os_desc request is queued but not completed
445 * One of these devices is allocated and initialized before the
446 * associated device driver's bind() is called.
448 * OPEN ISSUE: it appears that some WUSB devices will need to be
449 * built by combining a normal (wired) gadget with a wireless one.
450 * This revision of the gadget framework should probably try to make
451 * sure doing that won't hurt too much.
453 * One notion for how to handle Wireless USB devices involves:
455 * (a) a second gadget here, discovery mechanism TBD, but likely
456 * needing separate "register/unregister WUSB gadget" calls;
457 * (b) updates to usb_gadget to include flags "is it wireless",
458 * "is it wired", plus (presumably in a wrapper structure)
459 * bandgroup and PHY info;
460 * (c) presumably a wireless_ep wrapping a usb_ep, and reporting
461 * wireless-specific parameters like maxburst and maxsequence;
462 * (d) configurations that are specific to wireless links;
463 * (e) function drivers that understand wireless configs and will
464 * support wireless for (additional) function instances;
465 * (f) a function to support association setup (like CBAF), not
466 * necessarily requiring a wireless adapter;
467 * (g) composite device setup that can create one or more wireless
468 * configs, including appropriate association setup support;
471 struct usb_composite_dev
{
472 struct usb_gadget
*gadget
;
473 struct usb_request
*req
;
474 struct usb_request
*os_desc_req
;
476 struct usb_configuration
*config
;
478 /* OS String is a custom (yet popular) extension to the USB standard. */
479 u8 qw_sign
[OS_STRING_QW_SIGN_LEN
];
481 struct usb_configuration
*os_desc_config
;
482 unsigned int use_os_string
:1;
486 unsigned int suspended
:1;
487 struct usb_device_descriptor desc
;
488 struct list_head configs
;
489 struct list_head gstrings
;
490 struct usb_composite_driver
*driver
;
492 char *def_manufacturer
;
494 /* the gadget driver won't enable the data pullup
495 * while the deactivation count is nonzero.
497 unsigned deactivations
;
499 /* the composite driver won't complete the control transfer's
500 * data/status stages till delayed_status is zero.
504 /* protects deactivations and delayed_status counts*/
508 unsigned int setup_pending
:1;
509 unsigned int os_desc_pending
:1;
512 extern int usb_string_id(struct usb_composite_dev
*c
);
513 extern int usb_string_ids_tab(struct usb_composite_dev
*c
,
514 struct usb_string
*str
);
515 extern struct usb_string
*usb_gstrings_attach(struct usb_composite_dev
*cdev
,
516 struct usb_gadget_strings
**sp
, unsigned n_strings
);
518 extern int usb_string_ids_n(struct usb_composite_dev
*c
, unsigned n
);
520 extern void composite_disconnect(struct usb_gadget
*gadget
);
521 extern int composite_setup(struct usb_gadget
*gadget
,
522 const struct usb_ctrlrequest
*ctrl
);
523 extern void composite_suspend(struct usb_gadget
*gadget
);
524 extern void composite_resume(struct usb_gadget
*gadget
);
527 * Some systems will need runtime overrides for the product identifiers
528 * published in the device descriptor, either numbers or strings or both.
529 * String parameters are in UTF-8 (superset of ASCII's 7 bit characters).
531 struct usb_composite_overwrite
{
539 #define USB_GADGET_COMPOSITE_OPTIONS() \
540 static struct usb_composite_overwrite coverwrite; \
542 module_param_named(idVendor, coverwrite.idVendor, ushort, S_IRUGO); \
543 MODULE_PARM_DESC(idVendor, "USB Vendor ID"); \
545 module_param_named(idProduct, coverwrite.idProduct, ushort, S_IRUGO); \
546 MODULE_PARM_DESC(idProduct, "USB Product ID"); \
548 module_param_named(bcdDevice, coverwrite.bcdDevice, ushort, S_IRUGO); \
549 MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)"); \
551 module_param_named(iSerialNumber, coverwrite.serial_number, charp, \
553 MODULE_PARM_DESC(iSerialNumber, "SerialNumber string"); \
555 module_param_named(iManufacturer, coverwrite.manufacturer, charp, \
557 MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string"); \
559 module_param_named(iProduct, coverwrite.product, charp, S_IRUGO); \
560 MODULE_PARM_DESC(iProduct, "USB Product string")
562 void usb_composite_overwrite_options(struct usb_composite_dev
*cdev
,
563 struct usb_composite_overwrite
*covr
);
565 static inline u16
get_default_bcdDevice(void)
569 bcdDevice
= bin2bcd((LINUX_VERSION_CODE
>> 16 & 0xff)) << 8;
570 bcdDevice
|= bin2bcd((LINUX_VERSION_CODE
>> 8 & 0xff));
574 struct usb_function_driver
{
577 struct list_head list
;
578 struct usb_function_instance
*(*alloc_inst
)(void);
579 struct usb_function
*(*alloc_func
)(struct usb_function_instance
*inst
);
582 struct usb_function_instance
{
583 struct config_group group
;
584 struct list_head cfs_list
;
585 struct usb_function_driver
*fd
;
586 int (*set_inst_name
)(struct usb_function_instance
*inst
,
588 void (*free_func_inst
)(struct usb_function_instance
*inst
);
591 void usb_function_unregister(struct usb_function_driver
*f
);
592 int usb_function_register(struct usb_function_driver
*newf
);
593 void usb_put_function_instance(struct usb_function_instance
*fi
);
594 void usb_put_function(struct usb_function
*f
);
595 struct usb_function_instance
*usb_get_function_instance(const char *name
);
596 struct usb_function
*usb_get_function(struct usb_function_instance
*fi
);
598 struct usb_configuration
*usb_get_config(struct usb_composite_dev
*cdev
,
600 int usb_add_config_only(struct usb_composite_dev
*cdev
,
601 struct usb_configuration
*config
);
602 void usb_remove_function(struct usb_configuration
*c
, struct usb_function
*f
);
604 #define DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \
605 static struct usb_function_driver _name ## usb_func = { \
606 .name = __stringify(_name), \
607 .mod = THIS_MODULE, \
608 .alloc_inst = _inst_alloc, \
609 .alloc_func = _func_alloc, \
611 MODULE_ALIAS("usbfunc:"__stringify(_name));
613 #define DECLARE_USB_FUNCTION_INIT(_name, _inst_alloc, _func_alloc) \
614 DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \
615 static int __init _name ## mod_init(void) \
617 return usb_function_register(&_name ## usb_func); \
619 static void __exit _name ## mod_exit(void) \
621 usb_function_unregister(&_name ## usb_func); \
623 module_init(_name ## mod_init); \
624 module_exit(_name ## mod_exit)
626 /* messaging utils */
627 #define DBG(d, fmt, args...) \
628 dev_dbg(&(d)->gadget->dev , fmt , ## args)
629 #define VDBG(d, fmt, args...) \
630 dev_vdbg(&(d)->gadget->dev , fmt , ## args)
631 #define ERROR(d, fmt, args...) \
632 dev_err(&(d)->gadget->dev , fmt , ## args)
633 #define WARNING(d, fmt, args...) \
634 dev_warn(&(d)->gadget->dev , fmt , ## args)
635 #define INFO(d, fmt, args...) \
636 dev_info(&(d)->gadget->dev , fmt , ## args)
638 #endif /* __LINUX_USB_COMPOSITE_H */