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>
44 * USB function drivers should return USB_GADGET_DELAYED_STATUS if they
45 * wish to delay the data/status stages of the control transfer till they
46 * are ready. The control transfer will then be kept from completing till
47 * all the function drivers that requested for USB_GADGET_DELAYED_STAUS
48 * invoke usb_composite_setup_continue().
50 #define USB_GADGET_DELAYED_STATUS 0x7fff /* Impossibly large value */
52 /* big enough to hold our biggest descriptor */
53 #define USB_COMP_EP0_BUFSIZ 1024
55 #define USB_MS_TO_HS_INTERVAL(x) (ilog2((x * 1000 / 125)) + 1)
56 struct usb_configuration;
59 * struct usb_function - describes one function of a configuration
60 * @name: For diagnostics, identifies the function.
61 * @strings: tables of strings, keyed by identifiers assigned during bind()
62 * and by language IDs provided in control requests
63 * @descriptors: Table of full (or low) speed descriptors, using interface and
64 * string identifiers assigned during @bind(). If this pointer is null,
65 * the function will not be available at full speed (or at low speed).
66 * @hs_descriptors: Table of high speed descriptors, using interface and
67 * string identifiers assigned during @bind(). If this pointer is null,
68 * the function will not be available at high speed.
69 * @ss_descriptors: Table of super speed descriptors, using interface and
70 * string identifiers assigned during @bind(). If this
71 * pointer is null after initiation, the function will not
72 * be available at super speed.
73 * @config: assigned when @usb_add_function() is called; this is the
74 * configuration with which this function is associated.
75 * @bind: Before the gadget can register, all of its functions bind() to the
76 * available resources including string and interface identifiers used
77 * in interface or class descriptors; endpoints; I/O buffers; and so on.
78 * @unbind: Reverses @bind; called as a side effect of unregistering the
79 * driver which added this function.
80 * @free_func: free the struct usb_function.
81 * @mod: (internal) points to the module that created this structure.
82 * @set_alt: (REQUIRED) Reconfigures altsettings; function drivers may
83 * initialize usb_ep.driver data at this time (when it is used).
84 * Note that setting an interface to its current altsetting resets
85 * interface state, and that all interfaces have a disabled state.
86 * @get_alt: Returns the active altsetting. If this is not provided,
87 * then only altsetting zero is supported.
88 * @disable: (REQUIRED) Indicates the function should be disabled. Reasons
89 * include host resetting or reconfiguring the gadget, and disconnection.
90 * @setup: Used for interface-specific control requests.
91 * @suspend: Notifies functions when the host stops sending USB traffic.
92 * @resume: Notifies functions when the host restarts USB traffic.
93 * @get_status: Returns function status as a reply to
94 * GetStatus() request when the recepient is Interface.
95 * @func_suspend: callback to be called when
96 * SetFeature(FUNCTION_SUSPEND) is reseived
98 * A single USB function uses one or more interfaces, and should in most
99 * cases support operation at both full and high speeds. Each function is
100 * associated by @usb_add_function() with a one configuration; that function
101 * causes @bind() to be called so resources can be allocated as part of
102 * setting up a gadget driver. Those resources include endpoints, which
103 * should be allocated using @usb_ep_autoconfig().
105 * To support dual speed operation, a function driver provides descriptors
106 * for both high and full speed operation. Except in rare cases that don't
107 * involve bulk endpoints, each speed needs different endpoint descriptors.
109 * Function drivers choose their own strategies for managing instance data.
110 * The simplest strategy just declares it "static', which means the function
111 * can only be activated once. If the function needs to be exposed in more
112 * than one configuration at a given speed, it needs to support multiple
113 * usb_function structures (one for each configuration).
115 * A more complex strategy might encapsulate a @usb_function structure inside
116 * a driver-specific instance structure to allows multiple activations. An
117 * example of multiple activations might be a CDC ACM function that supports
118 * two or more distinct instances within the same configuration, providing
119 * several independent logical data links to a USB host.
122 struct usb_function {
124 struct usb_gadget_strings **strings;
125 struct usb_descriptor_header **fs_descriptors;
126 struct usb_descriptor_header **hs_descriptors;
127 struct usb_descriptor_header **ss_descriptors;
129 struct usb_configuration *config;
131 /* REVISIT: bind() functions can be marked __init, which
132 * makes trouble for section mismatch analysis. See if
133 * we can't restructure things to avoid mismatching.
134 * Related: unbind() may kfree() but bind() won't...
137 /* configuration management: bind/unbind */
138 int (*bind)(struct usb_configuration *,
139 struct usb_function *);
140 void (*unbind)(struct usb_configuration *,
141 struct usb_function *);
142 void (*free_func)(struct usb_function *f);
145 /* runtime state management */
146 int (*set_alt)(struct usb_function *,
147 unsigned interface, unsigned alt);
148 int (*get_alt)(struct usb_function *,
150 void (*disable)(struct usb_function *);
151 int (*setup)(struct usb_function *,
152 const struct usb_ctrlrequest *);
153 void (*suspend)(struct usb_function *);
154 void (*resume)(struct usb_function *);
156 /* USB 3.0 additions */
157 int (*get_status)(struct usb_function *);
158 int (*func_suspend)(struct usb_function *,
162 struct list_head list;
163 DECLARE_BITMAP(endpoints, 32);
164 const struct usb_function_instance *fi;
167 int usb_add_function(struct usb_configuration *, struct usb_function *);
169 int usb_function_deactivate(struct usb_function *);
170 int usb_function_activate(struct usb_function *);
172 int usb_interface_id(struct usb_configuration *, struct usb_function *);
174 int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f,
177 #define MAX_CONFIG_INTERFACES 16 /* arbitrary; max 255 */
180 * struct usb_configuration - represents one gadget configuration
181 * @label: For diagnostics, describes the configuration.
182 * @strings: Tables of strings, keyed by identifiers assigned during @bind()
183 * and by language IDs provided in control requests.
184 * @descriptors: Table of descriptors preceding all function descriptors.
185 * Examples include OTG and vendor-specific descriptors.
186 * @unbind: Reverses @bind; called as a side effect of unregistering the
187 * driver which added this configuration.
188 * @setup: Used to delegate control requests that aren't handled by standard
189 * device infrastructure or directed at a specific interface.
190 * @bConfigurationValue: Copied into configuration descriptor.
191 * @iConfiguration: Copied into configuration descriptor.
192 * @bmAttributes: Copied into configuration descriptor.
193 * @MaxPower: Power consumtion in mA. Used to compute bMaxPower in the
194 * configuration descriptor after considering the bus speed.
195 * @cdev: assigned by @usb_add_config() before calling @bind(); this is
196 * the device associated with this configuration.
198 * Configurations are building blocks for gadget drivers structured around
199 * function drivers. Simple USB gadgets require only one function and one
200 * configuration, and handle dual-speed hardware by always providing the same
201 * functionality. Slightly more complex gadgets may have more than one
202 * single-function configuration at a given speed; or have configurations
203 * that only work at one speed.
205 * Composite devices are, by definition, ones with configurations which
206 * include more than one function.
208 * The lifecycle of a usb_configuration includes allocation, initialization
209 * of the fields described above, and calling @usb_add_config() to set up
210 * internal data and bind it to a specific device. The configuration's
211 * @bind() method is then used to initialize all the functions and then
212 * call @usb_add_function() for them.
214 * Those functions would normally be independent of each other, but that's
215 * not mandatory. CDC WMC devices are an example where functions often
216 * depend on other functions, with some functions subsidiary to others.
217 * Such interdependency may be managed in any way, so long as all of the
218 * descriptors complete by the time the composite driver returns from
219 * its bind() routine.
221 struct usb_configuration {
223 struct usb_gadget_strings **strings;
224 const struct usb_descriptor_header **descriptors;
226 /* REVISIT: bind() functions can be marked __init, which
227 * makes trouble for section mismatch analysis. See if
228 * we can't restructure things to avoid mismatching...
231 /* configuration management: unbind/setup */
232 void (*unbind)(struct usb_configuration *);
233 int (*setup)(struct usb_configuration *,
234 const struct usb_ctrlrequest *);
236 /* fields in the config descriptor */
237 u8 bConfigurationValue;
242 struct usb_composite_dev *cdev;
246 struct list_head list;
247 struct list_head functions;
248 u8 next_interface_id;
249 unsigned superspeed:1;
250 unsigned highspeed:1;
251 unsigned fullspeed:1;
252 struct usb_function *interface[MAX_CONFIG_INTERFACES];
255 int usb_add_config(struct usb_composite_dev *,
256 struct usb_configuration *,
257 int (*)(struct usb_configuration *));
259 void usb_remove_config(struct usb_composite_dev *,
260 struct usb_configuration *);
262 /* predefined index for usb_composite_driver */
264 USB_GADGET_MANUFACTURER_IDX = 0,
265 USB_GADGET_PRODUCT_IDX,
266 USB_GADGET_SERIAL_IDX,
267 USB_GADGET_FIRST_AVAIL_IDX,
271 * struct usb_composite_driver - groups configurations into a gadget
272 * @name: For diagnostics, identifies the driver.
273 * @dev: Template descriptor for the device, including default device
275 * @strings: tables of strings, keyed by identifiers assigned during @bind
276 * and language IDs provided in control requests. Note: The first entries
277 * are predefined. The first entry that may be used is
278 * USB_GADGET_FIRST_AVAIL_IDX
279 * @max_speed: Highest speed the driver supports.
280 * @needs_serial: set to 1 if the gadget needs userspace to provide
281 * a serial number. If one is not provided, warning will be printed.
282 * @bind: (REQUIRED) Used to allocate resources that are shared across the
283 * whole device, such as string IDs, and add its configurations using
284 * @usb_add_config(). This may fail by returning a negative errno
285 * value; it should return zero on successful initialization.
286 * @unbind: Reverses @bind; called as a side effect of unregistering
288 * @disconnect: optional driver disconnect method
289 * @suspend: Notifies when the host stops sending USB traffic,
290 * after function notifications
291 * @resume: Notifies configuration when the host restarts USB traffic,
292 * before function notifications
294 * Devices default to reporting self powered operation. Devices which rely
295 * on bus powered operation should report this in their @bind method.
297 * Before returning from @bind, various fields in the template descriptor
298 * may be overridden. These include the idVendor/idProduct/bcdDevice values
299 * normally to bind the appropriate host side driver, and the three strings
300 * (iManufacturer, iProduct, iSerialNumber) normally used to provide user
301 * meaningful device identifiers. (The strings will not be defined unless
302 * they are defined in @dev and @strings.) The correct ep0 maxpacket size
303 * is also reported, as defined by the underlying controller driver.
305 struct usb_composite_driver {
307 const struct usb_device_descriptor *dev;
308 struct usb_gadget_strings **strings;
309 enum usb_device_speed max_speed;
310 unsigned needs_serial:1;
312 int (*bind)(struct usb_composite_dev *cdev);
313 int (*unbind)(struct usb_composite_dev *);
315 void (*disconnect)(struct usb_composite_dev *);
317 /* global suspend hooks */
318 void (*suspend)(struct usb_composite_dev *);
319 void (*resume)(struct usb_composite_dev *);
320 struct usb_gadget_driver gadget_driver;
323 extern int usb_composite_probe(struct usb_composite_driver *driver);
324 extern void usb_composite_unregister(struct usb_composite_driver *driver);
325 extern void usb_composite_setup_continue(struct usb_composite_dev *cdev);
326 extern int composite_dev_prepare(struct usb_composite_driver *composite,
327 struct usb_composite_dev *cdev);
328 void composite_dev_cleanup(struct usb_composite_dev *cdev);
330 static inline struct usb_composite_driver *to_cdriver(
331 struct usb_gadget_driver *gdrv)
333 return container_of(gdrv, struct usb_composite_driver, gadget_driver);
337 * struct usb_composite_device - represents one composite usb gadget
338 * @gadget: read-only, abstracts the gadget's usb peripheral controller
339 * @req: used for control responses; buffer is pre-allocated
340 * @config: the currently active configuration
342 * One of these devices is allocated and initialized before the
343 * associated device driver's bind() is called.
345 * OPEN ISSUE: it appears that some WUSB devices will need to be
346 * built by combining a normal (wired) gadget with a wireless one.
347 * This revision of the gadget framework should probably try to make
348 * sure doing that won't hurt too much.
350 * One notion for how to handle Wireless USB devices involves:
351 * (a) a second gadget here, discovery mechanism TBD, but likely
352 * needing separate "register/unregister WUSB gadget" calls;
353 * (b) updates to usb_gadget to include flags "is it wireless",
354 * "is it wired", plus (presumably in a wrapper structure)
355 * bandgroup and PHY info;
356 * (c) presumably a wireless_ep wrapping a usb_ep, and reporting
357 * wireless-specific parameters like maxburst and maxsequence;
358 * (d) configurations that are specific to wireless links;
359 * (e) function drivers that understand wireless configs and will
360 * support wireless for (additional) function instances;
361 * (f) a function to support association setup (like CBAF), not
362 * necessarily requiring a wireless adapter;
363 * (g) composite device setup that can create one or more wireless
364 * configs, including appropriate association setup support;
367 struct usb_composite_dev {
368 struct usb_gadget *gadget;
369 struct usb_request *req;
371 struct usb_configuration *config;
375 unsigned int suspended:1;
376 struct usb_device_descriptor desc;
377 struct list_head configs;
378 struct list_head gstrings;
379 struct usb_composite_driver *driver;
381 char *def_manufacturer;
383 /* the gadget driver won't enable the data pullup
384 * while the deactivation count is nonzero.
386 unsigned deactivations;
388 /* the composite driver won't complete the control transfer's
389 * data/status stages till delayed_status is zero.
393 /* protects deactivations and delayed_status counts*/
397 extern int usb_string_id(struct usb_composite_dev *c);
398 extern int usb_string_ids_tab(struct usb_composite_dev *c,
399 struct usb_string *str);
400 extern struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
401 struct usb_gadget_strings **sp, unsigned n_strings);
403 extern int usb_string_ids_n(struct usb_composite_dev *c, unsigned n);
405 extern void composite_disconnect(struct usb_gadget *gadget);
406 extern int composite_setup(struct usb_gadget *gadget,
407 const struct usb_ctrlrequest *ctrl);
410 * Some systems will need runtime overrides for the product identifiers
411 * published in the device descriptor, either numbers or strings or both.
412 * String parameters are in UTF-8 (superset of ASCII's 7 bit characters).
414 struct usb_composite_overwrite {
422 #define USB_GADGET_COMPOSITE_OPTIONS() \
423 static struct usb_composite_overwrite coverwrite; \
425 module_param_named(idVendor, coverwrite.idVendor, ushort, S_IRUGO); \
426 MODULE_PARM_DESC(idVendor, "USB Vendor ID"); \
428 module_param_named(idProduct, coverwrite.idProduct, ushort, S_IRUGO); \
429 MODULE_PARM_DESC(idProduct, "USB Product ID"); \
431 module_param_named(bcdDevice, coverwrite.bcdDevice, ushort, S_IRUGO); \
432 MODULE_PARM_DESC(bcdDevice, "USB Device version (BCD)"); \
434 module_param_named(iSerialNumber, coverwrite.serial_number, charp, \
436 MODULE_PARM_DESC(iSerialNumber, "SerialNumber string"); \
438 module_param_named(iManufacturer, coverwrite.manufacturer, charp, \
440 MODULE_PARM_DESC(iManufacturer, "USB Manufacturer string"); \
442 module_param_named(iProduct, coverwrite.product, charp, S_IRUGO); \
443 MODULE_PARM_DESC(iProduct, "USB Product string")
445 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
446 struct usb_composite_overwrite *covr);
448 static inline u16 get_default_bcdDevice(void)
452 bcdDevice = bin2bcd((LINUX_VERSION_CODE >> 16 & 0xff)) << 8;
453 bcdDevice |= bin2bcd((LINUX_VERSION_CODE >> 8 & 0xff));
457 struct usb_function_driver {
460 struct list_head list;
461 struct usb_function_instance *(*alloc_inst)(void);
462 struct usb_function *(*alloc_func)(struct usb_function_instance *inst);
465 struct usb_function_instance {
466 struct usb_function_driver *fd;
467 void (*free_func_inst)(struct usb_function_instance *inst);
470 void usb_function_unregister(struct usb_function_driver *f);
471 int usb_function_register(struct usb_function_driver *newf);
472 void usb_put_function_instance(struct usb_function_instance *fi);
473 void usb_put_function(struct usb_function *f);
474 struct usb_function_instance *usb_get_function_instance(const char *name);
475 struct usb_function *usb_get_function(struct usb_function_instance *fi);
477 struct usb_configuration *usb_get_config(struct usb_composite_dev *cdev,
479 int usb_add_config_only(struct usb_composite_dev *cdev,
480 struct usb_configuration *config);
481 void usb_remove_function(struct usb_configuration *c, struct usb_function *f);
483 #define DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \
484 static struct usb_function_driver _name ## usb_func = { \
485 .name = __stringify(_name), \
486 .mod = THIS_MODULE, \
487 .alloc_inst = _inst_alloc, \
488 .alloc_func = _func_alloc, \
490 MODULE_ALIAS("usbfunc:"__stringify(_name));
492 #define DECLARE_USB_FUNCTION_INIT(_name, _inst_alloc, _func_alloc) \
493 DECLARE_USB_FUNCTION(_name, _inst_alloc, _func_alloc) \
494 static int __init _name ## mod_init(void) \
496 return usb_function_register(&_name ## usb_func); \
498 static void __exit _name ## mod_exit(void) \
500 usb_function_unregister(&_name ## usb_func); \
502 module_init(_name ## mod_init); \
503 module_exit(_name ## mod_exit)
505 /* messaging utils */
506 #define DBG(d, fmt, args...) \
507 dev_dbg(&(d)->gadget->dev , fmt , ## args)
508 #define VDBG(d, fmt, args...) \
509 dev_vdbg(&(d)->gadget->dev , fmt , ## args)
510 #define ERROR(d, fmt, args...) \
511 dev_err(&(d)->gadget->dev , fmt , ## args)
512 #define WARNING(d, fmt, args...) \
513 dev_warn(&(d)->gadget->dev , fmt , ## args)
514 #define INFO(d, fmt, args...) \
515 dev_info(&(d)->gadget->dev , fmt , ## args)
517 #endif /* __LINUX_USB_COMPOSITE_H */