2 * composite.c - infrastructure for Composite USB Gadgets
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.
12 /* #define VERBOSE_DEBUG */
14 #include <linux/kallsyms.h>
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/device.h>
19 #include <linux/utsname.h>
21 #include <linux/usb/composite.h>
22 #include <asm/unaligned.h>
25 * The code in this file is utility code, used to build a gadget driver
26 * from one or more "function" drivers, one or more "configuration"
27 * objects, and a "usb_composite_driver" by gluing them together along
28 * with the relevant device-wide data.
32 * next_ep_desc() - advance to the next EP descriptor
33 * @t: currect pointer within descriptor array
35 * Return: next EP descriptor or NULL
37 * Iterate over @t until either EP descriptor found or
38 * NULL (that indicates end of list) encountered
40 static struct usb_descriptor_header**
41 next_ep_desc(struct usb_descriptor_header **t)
44 if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
51 * for_each_ep_desc()- iterate over endpoint descriptors in the
53 * @start: pointer within descriptor array.
54 * @ep_desc: endpoint descriptor to use as the loop cursor
56 #define for_each_ep_desc(start, ep_desc) \
57 for (ep_desc = next_ep_desc(start); \
58 ep_desc; ep_desc = next_ep_desc(ep_desc+1))
61 * config_ep_by_speed() - configures the given endpoint
62 * according to gadget speed.
63 * @g: pointer to the gadget
65 * @_ep: the endpoint to configure
67 * Return: error code, 0 on success
69 * This function chooses the right descriptors for a given
70 * endpoint according to gadget speed and saves it in the
71 * endpoint desc field. If the endpoint already has a descriptor
72 * assigned to it - overwrites it with currently corresponding
73 * descriptor. The endpoint maxpacket field is updated according
74 * to the chosen descriptor.
75 * Note: the supplied function should hold all the descriptors
76 * for supported speeds
78 int config_ep_by_speed(struct usb_gadget *g,
79 struct usb_function *f,
82 struct usb_composite_dev *cdev = get_gadget_data(g);
83 struct usb_endpoint_descriptor *chosen_desc = NULL;
84 struct usb_descriptor_header **speed_desc = NULL;
86 struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
87 int want_comp_desc = 0;
89 struct usb_descriptor_header **d_spd; /* cursor for speed desc */
94 /* select desired speed */
97 if (gadget_is_superspeed(g)) {
98 speed_desc = f->ss_descriptors;
102 /* else: Fall trough */
104 if (gadget_is_dualspeed(g)) {
105 speed_desc = f->hs_descriptors;
108 /* else: fall through */
110 speed_desc = f->fs_descriptors;
112 /* find descriptors */
113 for_each_ep_desc(speed_desc, d_spd) {
114 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
115 if (chosen_desc->bEndpointAddress == _ep->address)
122 _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
123 _ep->desc = chosen_desc;
124 _ep->comp_desc = NULL;
131 * Companion descriptor should follow EP descriptor
132 * USB 3.0 spec, #9.6.7
134 comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
136 (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
138 _ep->comp_desc = comp_desc;
139 if (g->speed == USB_SPEED_SUPER) {
140 switch (usb_endpoint_type(_ep->desc)) {
141 case USB_ENDPOINT_XFER_ISOC:
142 /* mult: bits 1:0 of bmAttributes */
143 _ep->mult = comp_desc->bmAttributes & 0x3;
144 case USB_ENDPOINT_XFER_BULK:
145 case USB_ENDPOINT_XFER_INT:
146 _ep->maxburst = comp_desc->bMaxBurst + 1;
149 if (comp_desc->bMaxBurst != 0)
150 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
157 EXPORT_SYMBOL_GPL(config_ep_by_speed);
160 * usb_add_function() - add a function to a configuration
161 * @config: the configuration
162 * @function: the function being added
163 * Context: single threaded during gadget setup
165 * After initialization, each configuration must have one or more
166 * functions added to it. Adding a function involves calling its @bind()
167 * method to allocate resources such as interface and string identifiers
170 * This function returns the value of the function's bind(), which is
171 * zero for success else a negative errno value.
173 int usb_add_function(struct usb_configuration *config,
174 struct usb_function *function)
178 DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
179 function->name, function,
180 config->label, config);
182 if (!function->set_alt || !function->disable)
185 function->config = config;
186 list_add_tail(&function->list, &config->functions);
188 /* REVISIT *require* function->bind? */
189 if (function->bind) {
190 value = function->bind(config, function);
192 list_del(&function->list);
193 function->config = NULL;
198 /* We allow configurations that don't work at both speeds.
199 * If we run into a lowspeed Linux system, treat it the same
200 * as full speed ... it's the function drivers that will need
201 * to avoid bulk and ISO transfers.
203 if (!config->fullspeed && function->fs_descriptors)
204 config->fullspeed = true;
205 if (!config->highspeed && function->hs_descriptors)
206 config->highspeed = true;
207 if (!config->superspeed && function->ss_descriptors)
208 config->superspeed = true;
212 DBG(config->cdev, "adding '%s'/%p --> %d\n",
213 function->name, function, value);
216 EXPORT_SYMBOL_GPL(usb_add_function);
218 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
223 bitmap_zero(f->endpoints, 32);
228 EXPORT_SYMBOL_GPL(usb_remove_function);
231 * usb_function_deactivate - prevent function and gadget enumeration
232 * @function: the function that isn't yet ready to respond
234 * Blocks response of the gadget driver to host enumeration by
235 * preventing the data line pullup from being activated. This is
236 * normally called during @bind() processing to change from the
237 * initial "ready to respond" state, or when a required resource
240 * For example, drivers that serve as a passthrough to a userspace
241 * daemon can block enumeration unless that daemon (such as an OBEX,
242 * MTP, or print server) is ready to handle host requests.
244 * Not all systems support software control of their USB peripheral
247 * Returns zero on success, else negative errno.
249 int usb_function_deactivate(struct usb_function *function)
251 struct usb_composite_dev *cdev = function->config->cdev;
255 spin_lock_irqsave(&cdev->lock, flags);
257 if (cdev->deactivations == 0)
258 status = usb_gadget_disconnect(cdev->gadget);
260 cdev->deactivations++;
262 spin_unlock_irqrestore(&cdev->lock, flags);
265 EXPORT_SYMBOL_GPL(usb_function_deactivate);
268 * usb_function_activate - allow function and gadget enumeration
269 * @function: function on which usb_function_activate() was called
271 * Reverses effect of usb_function_deactivate(). If no more functions
272 * are delaying their activation, the gadget driver will respond to
273 * host enumeration procedures.
275 * Returns zero on success, else negative errno.
277 int usb_function_activate(struct usb_function *function)
279 struct usb_composite_dev *cdev = function->config->cdev;
283 spin_lock_irqsave(&cdev->lock, flags);
285 if (WARN_ON(cdev->deactivations == 0))
288 cdev->deactivations--;
289 if (cdev->deactivations == 0)
290 status = usb_gadget_connect(cdev->gadget);
293 spin_unlock_irqrestore(&cdev->lock, flags);
296 EXPORT_SYMBOL_GPL(usb_function_activate);
299 * usb_interface_id() - allocate an unused interface ID
300 * @config: configuration associated with the interface
301 * @function: function handling the interface
302 * Context: single threaded during gadget setup
304 * usb_interface_id() is called from usb_function.bind() callbacks to
305 * allocate new interface IDs. The function driver will then store that
306 * ID in interface, association, CDC union, and other descriptors. It
307 * will also handle any control requests targeted at that interface,
308 * particularly changing its altsetting via set_alt(). There may
309 * also be class-specific or vendor-specific requests to handle.
311 * All interface identifier should be allocated using this routine, to
312 * ensure that for example different functions don't wrongly assign
313 * different meanings to the same identifier. Note that since interface
314 * identifiers are configuration-specific, functions used in more than
315 * one configuration (or more than once in a given configuration) need
316 * multiple versions of the relevant descriptors.
318 * Returns the interface ID which was allocated; or -ENODEV if no
319 * more interface IDs can be allocated.
321 int usb_interface_id(struct usb_configuration *config,
322 struct usb_function *function)
324 unsigned id = config->next_interface_id;
326 if (id < MAX_CONFIG_INTERFACES) {
327 config->interface[id] = function;
328 config->next_interface_id = id + 1;
333 EXPORT_SYMBOL_GPL(usb_interface_id);
335 static u8 encode_bMaxPower(enum usb_device_speed speed,
336 struct usb_configuration *c)
343 val = CONFIG_USB_GADGET_VBUS_DRAW;
347 case USB_SPEED_SUPER:
348 return DIV_ROUND_UP(val, 8);
350 return DIV_ROUND_UP(val, 2);
354 static int config_buf(struct usb_configuration *config,
355 enum usb_device_speed speed, void *buf, u8 type)
357 struct usb_config_descriptor *c = buf;
358 void *next = buf + USB_DT_CONFIG_SIZE;
360 struct usb_function *f;
363 len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
364 /* write the config descriptor */
366 c->bLength = USB_DT_CONFIG_SIZE;
367 c->bDescriptorType = type;
368 /* wTotalLength is written later */
369 c->bNumInterfaces = config->next_interface_id;
370 c->bConfigurationValue = config->bConfigurationValue;
371 c->iConfiguration = config->iConfiguration;
372 c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
373 c->bMaxPower = encode_bMaxPower(speed, config);
375 /* There may be e.g. OTG descriptors */
376 if (config->descriptors) {
377 status = usb_descriptor_fillbuf(next, len,
378 config->descriptors);
385 /* add each function's descriptors */
386 list_for_each_entry(f, &config->functions, list) {
387 struct usb_descriptor_header **descriptors;
390 case USB_SPEED_SUPER:
391 descriptors = f->ss_descriptors;
394 descriptors = f->hs_descriptors;
397 descriptors = f->fs_descriptors;
402 status = usb_descriptor_fillbuf(next, len,
403 (const struct usb_descriptor_header **) descriptors);
411 c->wTotalLength = cpu_to_le16(len);
415 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
417 struct usb_gadget *gadget = cdev->gadget;
418 struct usb_configuration *c;
419 u8 type = w_value >> 8;
420 enum usb_device_speed speed = USB_SPEED_UNKNOWN;
422 if (gadget->speed == USB_SPEED_SUPER)
423 speed = gadget->speed;
424 else if (gadget_is_dualspeed(gadget)) {
426 if (gadget->speed == USB_SPEED_HIGH)
428 if (type == USB_DT_OTHER_SPEED_CONFIG)
431 speed = USB_SPEED_HIGH;
435 /* This is a lookup by config *INDEX* */
437 list_for_each_entry(c, &cdev->configs, list) {
438 /* ignore configs that won't work at this speed */
440 case USB_SPEED_SUPER:
454 return config_buf(c, speed, cdev->req->buf, type);
460 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
462 struct usb_gadget *gadget = cdev->gadget;
463 struct usb_configuration *c;
468 if (gadget_is_dualspeed(gadget)) {
469 if (gadget->speed == USB_SPEED_HIGH)
471 if (gadget->speed == USB_SPEED_SUPER)
473 if (type == USB_DT_DEVICE_QUALIFIER)
476 list_for_each_entry(c, &cdev->configs, list) {
477 /* ignore configs that won't work at this speed */
494 * bos_desc() - prepares the BOS descriptor.
495 * @cdev: pointer to usb_composite device to generate the bos
498 * This function generates the BOS (Binary Device Object)
499 * descriptor and its device capabilities descriptors. The BOS
500 * descriptor should be supported by a SuperSpeed device.
502 static int bos_desc(struct usb_composite_dev *cdev)
504 struct usb_ext_cap_descriptor *usb_ext;
505 struct usb_ss_cap_descriptor *ss_cap;
506 struct usb_dcd_config_params dcd_config_params;
507 struct usb_bos_descriptor *bos = cdev->req->buf;
509 bos->bLength = USB_DT_BOS_SIZE;
510 bos->bDescriptorType = USB_DT_BOS;
512 bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
513 bos->bNumDeviceCaps = 0;
516 * A SuperSpeed device shall include the USB2.0 extension descriptor
517 * and shall support LPM when operating in USB2.0 HS mode.
519 usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
520 bos->bNumDeviceCaps++;
521 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
522 usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
523 usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
524 usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
525 usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT);
528 * The Superspeed USB Capability descriptor shall be implemented by all
529 * SuperSpeed devices.
531 ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
532 bos->bNumDeviceCaps++;
533 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
534 ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
535 ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
536 ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
537 ss_cap->bmAttributes = 0; /* LTM is not supported yet */
538 ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
539 USB_FULL_SPEED_OPERATION |
540 USB_HIGH_SPEED_OPERATION |
541 USB_5GBPS_OPERATION);
542 ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
544 /* Get Controller configuration */
545 if (cdev->gadget->ops->get_config_params)
546 cdev->gadget->ops->get_config_params(&dcd_config_params);
548 dcd_config_params.bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT;
549 dcd_config_params.bU2DevExitLat =
550 cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
552 ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
553 ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
555 return le16_to_cpu(bos->wTotalLength);
558 static void device_qual(struct usb_composite_dev *cdev)
560 struct usb_qualifier_descriptor *qual = cdev->req->buf;
562 qual->bLength = sizeof(*qual);
563 qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
564 /* POLICY: same bcdUSB and device type info at both speeds */
565 qual->bcdUSB = cdev->desc.bcdUSB;
566 qual->bDeviceClass = cdev->desc.bDeviceClass;
567 qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
568 qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
569 /* ASSUME same EP0 fifo size at both speeds */
570 qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
571 qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
575 /*-------------------------------------------------------------------------*/
577 static void reset_config(struct usb_composite_dev *cdev)
579 struct usb_function *f;
581 DBG(cdev, "reset config\n");
583 list_for_each_entry(f, &cdev->config->functions, list) {
587 bitmap_zero(f->endpoints, 32);
592 static int set_config(struct usb_composite_dev *cdev,
593 const struct usb_ctrlrequest *ctrl, unsigned number)
595 struct usb_gadget *gadget = cdev->gadget;
596 struct usb_configuration *c = NULL;
597 int result = -EINVAL;
598 unsigned power = gadget_is_otg(gadget) ? 8 : 100;
602 list_for_each_entry(c, &cdev->configs, list) {
603 if (c->bConfigurationValue == number) {
605 * We disable the FDs of the previous
606 * configuration only if the new configuration
617 } else { /* Zero configuration value - need to reset the config */
623 INFO(cdev, "%s config #%d: %s\n",
624 usb_speed_string(gadget->speed),
625 number, c ? c->label : "unconfigured");
632 /* Initialize all interfaces by setting them to altsetting zero. */
633 for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
634 struct usb_function *f = c->interface[tmp];
635 struct usb_descriptor_header **descriptors;
641 * Record which endpoints are used by the function. This is used
642 * to dispatch control requests targeted at that endpoint to the
643 * function's setup callback instead of the current
644 * configuration's setup callback.
646 switch (gadget->speed) {
647 case USB_SPEED_SUPER:
648 descriptors = f->ss_descriptors;
651 descriptors = f->hs_descriptors;
654 descriptors = f->fs_descriptors;
657 for (; *descriptors; ++descriptors) {
658 struct usb_endpoint_descriptor *ep;
661 if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
664 ep = (struct usb_endpoint_descriptor *)*descriptors;
665 addr = ((ep->bEndpointAddress & 0x80) >> 3)
666 | (ep->bEndpointAddress & 0x0f);
667 set_bit(addr, f->endpoints);
670 result = f->set_alt(f, tmp, 0);
672 DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
673 tmp, f->name, f, result);
679 if (result == USB_GADGET_DELAYED_STATUS) {
681 "%s: interface %d (%s) requested delayed status\n",
682 __func__, tmp, f->name);
683 cdev->delayed_status++;
684 DBG(cdev, "delayed_status count %d\n",
685 cdev->delayed_status);
689 /* when we return, be sure our power usage is valid */
690 power = c->MaxPower ? c->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
692 usb_gadget_vbus_draw(gadget, power);
693 if (result >= 0 && cdev->delayed_status)
694 result = USB_GADGET_DELAYED_STATUS;
698 int usb_add_config_only(struct usb_composite_dev *cdev,
699 struct usb_configuration *config)
701 struct usb_configuration *c;
703 if (!config->bConfigurationValue)
706 /* Prevent duplicate configuration identifiers */
707 list_for_each_entry(c, &cdev->configs, list) {
708 if (c->bConfigurationValue == config->bConfigurationValue)
713 list_add_tail(&config->list, &cdev->configs);
715 INIT_LIST_HEAD(&config->functions);
716 config->next_interface_id = 0;
717 memset(config->interface, 0, sizeof(config->interface));
721 EXPORT_SYMBOL_GPL(usb_add_config_only);
724 * usb_add_config() - add a configuration to a device.
725 * @cdev: wraps the USB gadget
726 * @config: the configuration, with bConfigurationValue assigned
727 * @bind: the configuration's bind function
728 * Context: single threaded during gadget setup
730 * One of the main tasks of a composite @bind() routine is to
731 * add each of the configurations it supports, using this routine.
733 * This function returns the value of the configuration's @bind(), which
734 * is zero for success else a negative errno value. Binding configurations
735 * assigns global resources including string IDs, and per-configuration
736 * resources such as interface IDs and endpoints.
738 int usb_add_config(struct usb_composite_dev *cdev,
739 struct usb_configuration *config,
740 int (*bind)(struct usb_configuration *))
742 int status = -EINVAL;
747 DBG(cdev, "adding config #%u '%s'/%p\n",
748 config->bConfigurationValue,
749 config->label, config);
751 status = usb_add_config_only(cdev, config);
755 status = bind(config);
757 while (!list_empty(&config->functions)) {
758 struct usb_function *f;
760 f = list_first_entry(&config->functions,
761 struct usb_function, list);
764 DBG(cdev, "unbind function '%s'/%p\n",
766 f->unbind(config, f);
767 /* may free memory for "f" */
770 list_del(&config->list);
775 DBG(cdev, "cfg %d/%p speeds:%s%s%s\n",
776 config->bConfigurationValue, config,
777 config->superspeed ? " super" : "",
778 config->highspeed ? " high" : "",
780 ? (gadget_is_dualspeed(cdev->gadget)
785 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
786 struct usb_function *f = config->interface[i];
790 DBG(cdev, " interface %d = %s/%p\n",
795 /* set_alt(), or next bind(), sets up
796 * ep->driver_data as needed.
798 usb_ep_autoconfig_reset(cdev->gadget);
802 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
803 config->bConfigurationValue, status);
806 EXPORT_SYMBOL_GPL(usb_add_config);
808 static void remove_config(struct usb_composite_dev *cdev,
809 struct usb_configuration *config)
811 while (!list_empty(&config->functions)) {
812 struct usb_function *f;
814 f = list_first_entry(&config->functions,
815 struct usb_function, list);
818 DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
819 f->unbind(config, f);
820 /* may free memory for "f" */
823 list_del(&config->list);
824 if (config->unbind) {
825 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
826 config->unbind(config);
827 /* may free memory for "c" */
832 * usb_remove_config() - remove a configuration from a device.
833 * @cdev: wraps the USB gadget
834 * @config: the configuration
836 * Drivers must call usb_gadget_disconnect before calling this function
837 * to disconnect the device from the host and make sure the host will not
838 * try to enumerate the device while we are changing the config list.
840 void usb_remove_config(struct usb_composite_dev *cdev,
841 struct usb_configuration *config)
845 spin_lock_irqsave(&cdev->lock, flags);
847 if (cdev->config == config)
850 spin_unlock_irqrestore(&cdev->lock, flags);
852 remove_config(cdev, config);
855 /*-------------------------------------------------------------------------*/
857 /* We support strings in multiple languages ... string descriptor zero
858 * says which languages are supported. The typical case will be that
859 * only one language (probably English) is used, with I18N handled on
863 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
865 const struct usb_gadget_strings *s;
871 language = cpu_to_le16(s->language);
872 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
873 if (*tmp == language)
882 static int lookup_string(
883 struct usb_gadget_strings **sp,
889 struct usb_gadget_strings *s;
894 if (s->language != language)
896 value = usb_gadget_get_string(s, id, buf);
903 static int get_string(struct usb_composite_dev *cdev,
904 void *buf, u16 language, int id)
906 struct usb_composite_driver *composite = cdev->driver;
907 struct usb_configuration *c;
908 struct usb_function *f;
911 /* Yes, not only is USB's I18N support probably more than most
912 * folk will ever care about ... also, it's all supported here.
913 * (Except for UTF8 support for Unicode's "Astral Planes".)
916 /* 0 == report all available language codes */
918 struct usb_string_descriptor *s = buf;
919 struct usb_gadget_strings **sp;
922 s->bDescriptorType = USB_DT_STRING;
924 sp = composite->strings;
926 collect_langs(sp, s->wData);
928 list_for_each_entry(c, &cdev->configs, list) {
931 collect_langs(sp, s->wData);
933 list_for_each_entry(f, &c->functions, list) {
936 collect_langs(sp, s->wData);
940 for (len = 0; len <= 126 && s->wData[len]; len++)
945 s->bLength = 2 * (len + 1);
949 /* String IDs are device-scoped, so we look up each string
950 * table we're told about. These lookups are infrequent;
951 * simpler-is-better here.
953 if (composite->strings) {
954 len = lookup_string(composite->strings, buf, language, id);
958 list_for_each_entry(c, &cdev->configs, list) {
960 len = lookup_string(c->strings, buf, language, id);
964 list_for_each_entry(f, &c->functions, list) {
967 len = lookup_string(f->strings, buf, language, id);
976 * usb_string_id() - allocate an unused string ID
977 * @cdev: the device whose string descriptor IDs are being allocated
978 * Context: single threaded during gadget setup
980 * @usb_string_id() is called from bind() callbacks to allocate
981 * string IDs. Drivers for functions, configurations, or gadgets will
982 * then store that ID in the appropriate descriptors and string table.
984 * All string identifier should be allocated using this,
985 * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
986 * that for example different functions don't wrongly assign different
987 * meanings to the same identifier.
989 int usb_string_id(struct usb_composite_dev *cdev)
991 if (cdev->next_string_id < 254) {
992 /* string id 0 is reserved by USB spec for list of
993 * supported languages */
994 /* 255 reserved as well? -- mina86 */
995 cdev->next_string_id++;
996 return cdev->next_string_id;
1000 EXPORT_SYMBOL_GPL(usb_string_id);
1003 * usb_string_ids() - allocate unused string IDs in batch
1004 * @cdev: the device whose string descriptor IDs are being allocated
1005 * @str: an array of usb_string objects to assign numbers to
1006 * Context: single threaded during gadget setup
1008 * @usb_string_ids() is called from bind() callbacks to allocate
1009 * string IDs. Drivers for functions, configurations, or gadgets will
1010 * then copy IDs from the string table to the appropriate descriptors
1011 * and string table for other languages.
1013 * All string identifier should be allocated using this,
1014 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1015 * example different functions don't wrongly assign different meanings
1016 * to the same identifier.
1018 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1020 int next = cdev->next_string_id;
1022 for (; str->s; ++str) {
1023 if (unlikely(next >= 254))
1028 cdev->next_string_id = next;
1032 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1035 * usb_string_ids_n() - allocate unused string IDs in batch
1036 * @c: the device whose string descriptor IDs are being allocated
1037 * @n: number of string IDs to allocate
1038 * Context: single threaded during gadget setup
1040 * Returns the first requested ID. This ID and next @n-1 IDs are now
1041 * valid IDs. At least provided that @n is non-zero because if it
1042 * is, returns last requested ID which is now very useful information.
1044 * @usb_string_ids_n() is called from bind() callbacks to allocate
1045 * string IDs. Drivers for functions, configurations, or gadgets will
1046 * then store that ID in the appropriate descriptors and string table.
1048 * All string identifier should be allocated using this,
1049 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1050 * example different functions don't wrongly assign different meanings
1051 * to the same identifier.
1053 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1055 unsigned next = c->next_string_id;
1056 if (unlikely(n > 254 || (unsigned)next + n > 254))
1058 c->next_string_id += n;
1061 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1063 /*-------------------------------------------------------------------------*/
1065 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1067 if (req->status || req->actual != req->length)
1068 DBG((struct usb_composite_dev *) ep->driver_data,
1069 "setup complete --> %d, %d/%d\n",
1070 req->status, req->actual, req->length);
1074 * The setup() callback implements all the ep0 functionality that's
1075 * not handled lower down, in hardware or the hardware driver(like
1076 * device and endpoint feature flags, and their status). It's all
1077 * housekeeping for the gadget function we're implementing. Most of
1078 * the work is in config and function specific setup.
1081 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1083 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1084 struct usb_request *req = cdev->req;
1085 int value = -EOPNOTSUPP;
1087 u16 w_index = le16_to_cpu(ctrl->wIndex);
1088 u8 intf = w_index & 0xFF;
1089 u16 w_value = le16_to_cpu(ctrl->wValue);
1090 u16 w_length = le16_to_cpu(ctrl->wLength);
1091 struct usb_function *f = NULL;
1094 /* partial re-init of the response message; the function or the
1095 * gadget might need to intercept e.g. a control-OUT completion
1096 * when we delegate to it.
1099 req->complete = composite_setup_complete;
1101 gadget->ep0->driver_data = cdev;
1103 switch (ctrl->bRequest) {
1105 /* we handle all standard USB descriptors */
1106 case USB_REQ_GET_DESCRIPTOR:
1107 if (ctrl->bRequestType != USB_DIR_IN)
1109 switch (w_value >> 8) {
1112 cdev->desc.bNumConfigurations =
1113 count_configs(cdev, USB_DT_DEVICE);
1114 cdev->desc.bMaxPacketSize0 =
1115 cdev->gadget->ep0->maxpacket;
1116 if (gadget_is_superspeed(gadget)) {
1117 if (gadget->speed >= USB_SPEED_SUPER) {
1118 cdev->desc.bcdUSB = cpu_to_le16(0x0300);
1119 cdev->desc.bMaxPacketSize0 = 9;
1121 cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1125 value = min(w_length, (u16) sizeof cdev->desc);
1126 memcpy(req->buf, &cdev->desc, value);
1128 case USB_DT_DEVICE_QUALIFIER:
1129 if (!gadget_is_dualspeed(gadget) ||
1130 gadget->speed >= USB_SPEED_SUPER)
1133 value = min_t(int, w_length,
1134 sizeof(struct usb_qualifier_descriptor));
1136 case USB_DT_OTHER_SPEED_CONFIG:
1137 if (!gadget_is_dualspeed(gadget) ||
1138 gadget->speed >= USB_SPEED_SUPER)
1142 value = config_desc(cdev, w_value);
1144 value = min(w_length, (u16) value);
1147 value = get_string(cdev, req->buf,
1148 w_index, w_value & 0xff);
1150 value = min(w_length, (u16) value);
1153 if (gadget_is_superspeed(gadget)) {
1154 value = bos_desc(cdev);
1155 value = min(w_length, (u16) value);
1161 /* any number of configs can work */
1162 case USB_REQ_SET_CONFIGURATION:
1163 if (ctrl->bRequestType != 0)
1165 if (gadget_is_otg(gadget)) {
1166 if (gadget->a_hnp_support)
1167 DBG(cdev, "HNP available\n");
1168 else if (gadget->a_alt_hnp_support)
1169 DBG(cdev, "HNP on another port\n");
1171 VDBG(cdev, "HNP inactive\n");
1173 spin_lock(&cdev->lock);
1174 value = set_config(cdev, ctrl, w_value);
1175 spin_unlock(&cdev->lock);
1177 case USB_REQ_GET_CONFIGURATION:
1178 if (ctrl->bRequestType != USB_DIR_IN)
1181 *(u8 *)req->buf = cdev->config->bConfigurationValue;
1183 *(u8 *)req->buf = 0;
1184 value = min(w_length, (u16) 1);
1187 /* function drivers must handle get/set altsetting; if there's
1188 * no get() method, we know only altsetting zero works.
1190 case USB_REQ_SET_INTERFACE:
1191 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1193 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1195 f = cdev->config->interface[intf];
1198 if (w_value && !f->set_alt)
1200 value = f->set_alt(f, w_index, w_value);
1201 if (value == USB_GADGET_DELAYED_STATUS) {
1203 "%s: interface %d (%s) requested delayed status\n",
1204 __func__, intf, f->name);
1205 cdev->delayed_status++;
1206 DBG(cdev, "delayed_status count %d\n",
1207 cdev->delayed_status);
1210 case USB_REQ_GET_INTERFACE:
1211 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1213 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1215 f = cdev->config->interface[intf];
1218 /* lots of interfaces only need altsetting zero... */
1219 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1222 *((u8 *)req->buf) = value;
1223 value = min(w_length, (u16) 1);
1227 * USB 3.0 additions:
1228 * Function driver should handle get_status request. If such cb
1229 * wasn't supplied we respond with default value = 0
1230 * Note: function driver should supply such cb only for the first
1231 * interface of the function
1233 case USB_REQ_GET_STATUS:
1234 if (!gadget_is_superspeed(gadget))
1236 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1238 value = 2; /* This is the length of the get_status reply */
1239 put_unaligned_le16(0, req->buf);
1240 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1242 f = cdev->config->interface[intf];
1245 status = f->get_status ? f->get_status(f) : 0;
1248 put_unaligned_le16(status & 0x0000ffff, req->buf);
1251 * Function drivers should handle SetFeature/ClearFeature
1252 * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1253 * only for the first interface of the function
1255 case USB_REQ_CLEAR_FEATURE:
1256 case USB_REQ_SET_FEATURE:
1257 if (!gadget_is_superspeed(gadget))
1259 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1262 case USB_INTRF_FUNC_SUSPEND:
1263 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1265 f = cdev->config->interface[intf];
1269 if (f->func_suspend)
1270 value = f->func_suspend(f, w_index >> 8);
1273 "func_suspend() returned error %d\n",
1283 "non-core control req%02x.%02x v%04x i%04x l%d\n",
1284 ctrl->bRequestType, ctrl->bRequest,
1285 w_value, w_index, w_length);
1287 /* functions always handle their interfaces and endpoints...
1288 * punt other recipients (other, WUSB, ...) to the current
1289 * configuration code.
1291 * REVISIT it could make sense to let the composite device
1292 * take such requests too, if that's ever needed: to work
1295 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1296 case USB_RECIP_INTERFACE:
1297 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1299 f = cdev->config->interface[intf];
1302 case USB_RECIP_ENDPOINT:
1303 endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1304 list_for_each_entry(f, &cdev->config->functions, list) {
1305 if (test_bit(endp, f->endpoints))
1308 if (&f->list == &cdev->config->functions)
1314 value = f->setup(f, ctrl);
1316 struct usb_configuration *c;
1320 value = c->setup(c, ctrl);
1326 /* respond with data transfer before status phase? */
1327 if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1328 req->length = value;
1329 req->zero = value < w_length;
1330 value = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
1332 DBG(cdev, "ep_queue --> %d\n", value);
1334 composite_setup_complete(gadget->ep0, req);
1336 } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1338 "%s: Delayed status not supported for w_length != 0",
1343 /* device either stalls (value < 0) or reports success */
1347 static void composite_disconnect(struct usb_gadget *gadget)
1349 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1350 unsigned long flags;
1352 /* REVISIT: should we have config and device level
1353 * disconnect callbacks?
1355 spin_lock_irqsave(&cdev->lock, flags);
1358 if (cdev->driver->disconnect)
1359 cdev->driver->disconnect(cdev);
1360 spin_unlock_irqrestore(&cdev->lock, flags);
1363 /*-------------------------------------------------------------------------*/
1365 static ssize_t composite_show_suspended(struct device *dev,
1366 struct device_attribute *attr,
1369 struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1370 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1372 return sprintf(buf, "%d\n", cdev->suspended);
1375 static DEVICE_ATTR(suspended, 0444, composite_show_suspended, NULL);
1377 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
1379 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1381 /* composite_disconnect() must already have been called
1382 * by the underlying peripheral controller driver!
1383 * so there's no i/o concurrency that could affect the
1384 * state protected by cdev->lock.
1386 WARN_ON(cdev->config);
1388 while (!list_empty(&cdev->configs)) {
1389 struct usb_configuration *c;
1390 c = list_first_entry(&cdev->configs,
1391 struct usb_configuration, list);
1392 remove_config(cdev, c);
1394 if (cdev->driver->unbind && unbind_driver)
1395 cdev->driver->unbind(cdev);
1397 composite_dev_cleanup(cdev);
1399 kfree(cdev->def_manufacturer);
1401 set_gadget_data(gadget, NULL);
1404 static void composite_unbind(struct usb_gadget *gadget)
1406 __composite_unbind(gadget, true);
1409 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
1410 const struct usb_device_descriptor *old)
1420 * these variables may have been set in
1421 * usb_composite_overwrite_options()
1423 idVendor = new->idVendor;
1424 idProduct = new->idProduct;
1425 bcdDevice = new->bcdDevice;
1426 iSerialNumber = new->iSerialNumber;
1427 iManufacturer = new->iManufacturer;
1428 iProduct = new->iProduct;
1432 new->idVendor = idVendor;
1434 new->idProduct = idProduct;
1436 new->bcdDevice = bcdDevice;
1438 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
1440 new->iSerialNumber = iSerialNumber;
1442 new->iManufacturer = iManufacturer;
1444 new->iProduct = iProduct;
1447 int composite_dev_prepare(struct usb_composite_driver *composite,
1448 struct usb_composite_dev *cdev)
1450 struct usb_gadget *gadget = cdev->gadget;
1453 /* preallocate control response and buffer */
1454 cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
1458 cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
1459 if (!cdev->req->buf)
1462 ret = device_create_file(&gadget->dev, &dev_attr_suspended);
1466 cdev->req->complete = composite_setup_complete;
1467 gadget->ep0->driver_data = cdev;
1469 cdev->driver = composite;
1472 * As per USB compliance update, a device that is actively drawing
1473 * more than 100mA from USB must report itself as bus-powered in
1474 * the GetStatus(DEVICE) call.
1476 if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
1477 usb_gadget_set_selfpowered(gadget);
1479 /* interface and string IDs start at zero via kzalloc.
1480 * we force endpoints to start unassigned; few controller
1481 * drivers will zero ep->driver_data.
1483 usb_ep_autoconfig_reset(gadget);
1486 kfree(cdev->req->buf);
1488 usb_ep_free_request(gadget->ep0, cdev->req);
1493 void composite_dev_cleanup(struct usb_composite_dev *cdev)
1496 kfree(cdev->req->buf);
1497 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
1499 device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
1502 static int composite_bind(struct usb_gadget *gadget,
1503 struct usb_gadget_driver *gdriver)
1505 struct usb_composite_dev *cdev;
1506 struct usb_composite_driver *composite = to_cdriver(gdriver);
1507 int status = -ENOMEM;
1509 cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
1513 spin_lock_init(&cdev->lock);
1514 cdev->gadget = gadget;
1515 set_gadget_data(gadget, cdev);
1516 INIT_LIST_HEAD(&cdev->configs);
1518 status = composite_dev_prepare(composite, cdev);
1522 /* composite gadget needs to assign strings for whole device (like
1523 * serial number), register function drivers, potentially update
1524 * power state and consumption, etc
1526 status = composite->bind(cdev);
1530 update_unchanged_dev_desc(&cdev->desc, composite->dev);
1532 /* has userspace failed to provide a serial number? */
1533 if (composite->needs_serial && !cdev->desc.iSerialNumber)
1534 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
1536 INFO(cdev, "%s ready\n", composite->name);
1540 __composite_unbind(gadget, false);
1544 /*-------------------------------------------------------------------------*/
1547 composite_suspend(struct usb_gadget *gadget)
1549 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1550 struct usb_function *f;
1552 /* REVISIT: should we have config level
1553 * suspend/resume callbacks?
1555 DBG(cdev, "suspend\n");
1557 list_for_each_entry(f, &cdev->config->functions, list) {
1562 if (cdev->driver->suspend)
1563 cdev->driver->suspend(cdev);
1565 cdev->suspended = 1;
1567 usb_gadget_vbus_draw(gadget, 2);
1571 composite_resume(struct usb_gadget *gadget)
1573 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1574 struct usb_function *f;
1577 /* REVISIT: should we have config level
1578 * suspend/resume callbacks?
1580 DBG(cdev, "resume\n");
1581 if (cdev->driver->resume)
1582 cdev->driver->resume(cdev);
1584 list_for_each_entry(f, &cdev->config->functions, list) {
1589 maxpower = cdev->config->MaxPower;
1591 usb_gadget_vbus_draw(gadget, maxpower ?
1592 maxpower : CONFIG_USB_GADGET_VBUS_DRAW);
1595 cdev->suspended = 0;
1598 /*-------------------------------------------------------------------------*/
1600 static const struct usb_gadget_driver composite_driver_template = {
1601 .bind = composite_bind,
1602 .unbind = composite_unbind,
1604 .setup = composite_setup,
1605 .disconnect = composite_disconnect,
1607 .suspend = composite_suspend,
1608 .resume = composite_resume,
1611 .owner = THIS_MODULE,
1616 * usb_composite_probe() - register a composite driver
1617 * @driver: the driver to register
1618 * @bind: the callback used to allocate resources that are shared across the
1619 * whole device, such as string IDs, and add its configurations using
1620 * @usb_add_config(). This may fail by returning a negative errno
1621 * value; it should return zero on successful initialization.
1622 * Context: single threaded during gadget setup
1624 * This function is used to register drivers using the composite driver
1625 * framework. The return value is zero, or a negative errno value.
1626 * Those values normally come from the driver's @bind method, which does
1627 * all the work of setting up the driver to match the hardware.
1629 * On successful return, the gadget is ready to respond to requests from
1630 * the host, unless one of its components invokes usb_gadget_disconnect()
1631 * while it was binding. That would usually be done in order to wait for
1632 * some userspace participation.
1634 int usb_composite_probe(struct usb_composite_driver *driver)
1636 struct usb_gadget_driver *gadget_driver;
1638 if (!driver || !driver->dev || !driver->bind)
1642 driver->name = "composite";
1644 driver->gadget_driver = composite_driver_template;
1645 gadget_driver = &driver->gadget_driver;
1647 gadget_driver->function = (char *) driver->name;
1648 gadget_driver->driver.name = driver->name;
1649 gadget_driver->max_speed = driver->max_speed;
1651 return usb_gadget_probe_driver(gadget_driver);
1653 EXPORT_SYMBOL_GPL(usb_composite_probe);
1656 * usb_composite_unregister() - unregister a composite driver
1657 * @driver: the driver to unregister
1659 * This function is used to unregister drivers using the composite
1662 void usb_composite_unregister(struct usb_composite_driver *driver)
1664 usb_gadget_unregister_driver(&driver->gadget_driver);
1666 EXPORT_SYMBOL_GPL(usb_composite_unregister);
1669 * usb_composite_setup_continue() - Continue with the control transfer
1670 * @cdev: the composite device who's control transfer was kept waiting
1672 * This function must be called by the USB function driver to continue
1673 * with the control transfer's data/status stage in case it had requested to
1674 * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
1675 * can request the composite framework to delay the setup request's data/status
1676 * stages by returning USB_GADGET_DELAYED_STATUS.
1678 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
1681 struct usb_request *req = cdev->req;
1682 unsigned long flags;
1684 DBG(cdev, "%s\n", __func__);
1685 spin_lock_irqsave(&cdev->lock, flags);
1687 if (cdev->delayed_status == 0) {
1688 WARN(cdev, "%s: Unexpected call\n", __func__);
1690 } else if (--cdev->delayed_status == 0) {
1691 DBG(cdev, "%s: Completing delayed status\n", __func__);
1693 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1695 DBG(cdev, "ep_queue --> %d\n", value);
1697 composite_setup_complete(cdev->gadget->ep0, req);
1701 spin_unlock_irqrestore(&cdev->lock, flags);
1703 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
1705 static char *composite_default_mfr(struct usb_gadget *gadget)
1710 len = snprintf(NULL, 0, "%s %s with %s", init_utsname()->sysname,
1711 init_utsname()->release, gadget->name);
1713 mfr = kmalloc(len, GFP_KERNEL);
1716 snprintf(mfr, len, "%s %s with %s", init_utsname()->sysname,
1717 init_utsname()->release, gadget->name);
1721 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
1722 struct usb_composite_overwrite *covr)
1724 struct usb_device_descriptor *desc = &cdev->desc;
1725 struct usb_gadget_strings *gstr = cdev->driver->strings[0];
1726 struct usb_string *dev_str = gstr->strings;
1729 desc->idVendor = cpu_to_le16(covr->idVendor);
1731 if (covr->idProduct)
1732 desc->idProduct = cpu_to_le16(covr->idProduct);
1734 if (covr->bcdDevice)
1735 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
1737 if (covr->serial_number) {
1738 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
1739 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
1741 if (covr->manufacturer) {
1742 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
1743 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
1745 } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
1746 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
1747 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
1748 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
1751 if (covr->product) {
1752 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
1753 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
1756 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
1758 MODULE_LICENSE("GPL");
1759 MODULE_AUTHOR("David Brownell");