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);
219 * usb_function_deactivate - prevent function and gadget enumeration
220 * @function: the function that isn't yet ready to respond
222 * Blocks response of the gadget driver to host enumeration by
223 * preventing the data line pullup from being activated. This is
224 * normally called during @bind() processing to change from the
225 * initial "ready to respond" state, or when a required resource
228 * For example, drivers that serve as a passthrough to a userspace
229 * daemon can block enumeration unless that daemon (such as an OBEX,
230 * MTP, or print server) is ready to handle host requests.
232 * Not all systems support software control of their USB peripheral
235 * Returns zero on success, else negative errno.
237 int usb_function_deactivate(struct usb_function *function)
239 struct usb_composite_dev *cdev = function->config->cdev;
243 spin_lock_irqsave(&cdev->lock, flags);
245 if (cdev->deactivations == 0)
246 status = usb_gadget_disconnect(cdev->gadget);
248 cdev->deactivations++;
250 spin_unlock_irqrestore(&cdev->lock, flags);
253 EXPORT_SYMBOL_GPL(usb_function_deactivate);
256 * usb_function_activate - allow function and gadget enumeration
257 * @function: function on which usb_function_activate() was called
259 * Reverses effect of usb_function_deactivate(). If no more functions
260 * are delaying their activation, the gadget driver will respond to
261 * host enumeration procedures.
263 * Returns zero on success, else negative errno.
265 int usb_function_activate(struct usb_function *function)
267 struct usb_composite_dev *cdev = function->config->cdev;
271 spin_lock_irqsave(&cdev->lock, flags);
273 if (WARN_ON(cdev->deactivations == 0))
276 cdev->deactivations--;
277 if (cdev->deactivations == 0)
278 status = usb_gadget_connect(cdev->gadget);
281 spin_unlock_irqrestore(&cdev->lock, flags);
284 EXPORT_SYMBOL_GPL(usb_function_activate);
287 * usb_interface_id() - allocate an unused interface ID
288 * @config: configuration associated with the interface
289 * @function: function handling the interface
290 * Context: single threaded during gadget setup
292 * usb_interface_id() is called from usb_function.bind() callbacks to
293 * allocate new interface IDs. The function driver will then store that
294 * ID in interface, association, CDC union, and other descriptors. It
295 * will also handle any control requests targeted at that interface,
296 * particularly changing its altsetting via set_alt(). There may
297 * also be class-specific or vendor-specific requests to handle.
299 * All interface identifier should be allocated using this routine, to
300 * ensure that for example different functions don't wrongly assign
301 * different meanings to the same identifier. Note that since interface
302 * identifiers are configuration-specific, functions used in more than
303 * one configuration (or more than once in a given configuration) need
304 * multiple versions of the relevant descriptors.
306 * Returns the interface ID which was allocated; or -ENODEV if no
307 * more interface IDs can be allocated.
309 int usb_interface_id(struct usb_configuration *config,
310 struct usb_function *function)
312 unsigned id = config->next_interface_id;
314 if (id < MAX_CONFIG_INTERFACES) {
315 config->interface[id] = function;
316 config->next_interface_id = id + 1;
321 EXPORT_SYMBOL_GPL(usb_interface_id);
323 static int config_buf(struct usb_configuration *config,
324 enum usb_device_speed speed, void *buf, u8 type)
326 struct usb_config_descriptor *c = buf;
327 void *next = buf + USB_DT_CONFIG_SIZE;
329 struct usb_function *f;
332 len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
333 /* write the config descriptor */
335 c->bLength = USB_DT_CONFIG_SIZE;
336 c->bDescriptorType = type;
337 /* wTotalLength is written later */
338 c->bNumInterfaces = config->next_interface_id;
339 c->bConfigurationValue = config->bConfigurationValue;
340 c->iConfiguration = config->iConfiguration;
341 c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
342 c->bMaxPower = config->bMaxPower ? : (CONFIG_USB_GADGET_VBUS_DRAW / 2);
344 /* There may be e.g. OTG descriptors */
345 if (config->descriptors) {
346 status = usb_descriptor_fillbuf(next, len,
347 config->descriptors);
354 /* add each function's descriptors */
355 list_for_each_entry(f, &config->functions, list) {
356 struct usb_descriptor_header **descriptors;
359 case USB_SPEED_SUPER:
360 descriptors = f->ss_descriptors;
363 descriptors = f->hs_descriptors;
366 descriptors = f->fs_descriptors;
371 status = usb_descriptor_fillbuf(next, len,
372 (const struct usb_descriptor_header **) descriptors);
380 c->wTotalLength = cpu_to_le16(len);
384 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
386 struct usb_gadget *gadget = cdev->gadget;
387 struct usb_configuration *c;
388 u8 type = w_value >> 8;
389 enum usb_device_speed speed = USB_SPEED_UNKNOWN;
391 if (gadget->speed == USB_SPEED_SUPER)
392 speed = gadget->speed;
393 else if (gadget_is_dualspeed(gadget)) {
395 if (gadget->speed == USB_SPEED_HIGH)
397 if (type == USB_DT_OTHER_SPEED_CONFIG)
400 speed = USB_SPEED_HIGH;
404 /* This is a lookup by config *INDEX* */
406 list_for_each_entry(c, &cdev->configs, list) {
407 /* ignore configs that won't work at this speed */
409 case USB_SPEED_SUPER:
423 return config_buf(c, speed, cdev->req->buf, type);
429 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
431 struct usb_gadget *gadget = cdev->gadget;
432 struct usb_configuration *c;
437 if (gadget_is_dualspeed(gadget)) {
438 if (gadget->speed == USB_SPEED_HIGH)
440 if (gadget->speed == USB_SPEED_SUPER)
442 if (type == USB_DT_DEVICE_QUALIFIER)
445 list_for_each_entry(c, &cdev->configs, list) {
446 /* ignore configs that won't work at this speed */
463 * bos_desc() - prepares the BOS descriptor.
464 * @cdev: pointer to usb_composite device to generate the bos
467 * This function generates the BOS (Binary Device Object)
468 * descriptor and its device capabilities descriptors. The BOS
469 * descriptor should be supported by a SuperSpeed device.
471 static int bos_desc(struct usb_composite_dev *cdev)
473 struct usb_ext_cap_descriptor *usb_ext;
474 struct usb_ss_cap_descriptor *ss_cap;
475 struct usb_dcd_config_params dcd_config_params;
476 struct usb_bos_descriptor *bos = cdev->req->buf;
478 bos->bLength = USB_DT_BOS_SIZE;
479 bos->bDescriptorType = USB_DT_BOS;
481 bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
482 bos->bNumDeviceCaps = 0;
485 * A SuperSpeed device shall include the USB2.0 extension descriptor
486 * and shall support LPM when operating in USB2.0 HS mode.
488 usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
489 bos->bNumDeviceCaps++;
490 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
491 usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
492 usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
493 usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
494 usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT);
497 * The Superspeed USB Capability descriptor shall be implemented by all
498 * SuperSpeed devices.
500 ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
501 bos->bNumDeviceCaps++;
502 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
503 ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
504 ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
505 ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
506 ss_cap->bmAttributes = 0; /* LTM is not supported yet */
507 ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
508 USB_FULL_SPEED_OPERATION |
509 USB_HIGH_SPEED_OPERATION |
510 USB_5GBPS_OPERATION);
511 ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
513 /* Get Controller configuration */
514 if (cdev->gadget->ops->get_config_params)
515 cdev->gadget->ops->get_config_params(&dcd_config_params);
517 dcd_config_params.bU1devExitLat = USB_DEFAULT_U1_DEV_EXIT_LAT;
518 dcd_config_params.bU2DevExitLat =
519 cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
521 ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
522 ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
524 return le16_to_cpu(bos->wTotalLength);
527 static void device_qual(struct usb_composite_dev *cdev)
529 struct usb_qualifier_descriptor *qual = cdev->req->buf;
531 qual->bLength = sizeof(*qual);
532 qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
533 /* POLICY: same bcdUSB and device type info at both speeds */
534 qual->bcdUSB = cdev->desc.bcdUSB;
535 qual->bDeviceClass = cdev->desc.bDeviceClass;
536 qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
537 qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
538 /* ASSUME same EP0 fifo size at both speeds */
539 qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
540 qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
544 /*-------------------------------------------------------------------------*/
546 static void reset_config(struct usb_composite_dev *cdev)
548 struct usb_function *f;
550 DBG(cdev, "reset config\n");
552 list_for_each_entry(f, &cdev->config->functions, list) {
556 bitmap_zero(f->endpoints, 32);
561 static int set_config(struct usb_composite_dev *cdev,
562 const struct usb_ctrlrequest *ctrl, unsigned number)
564 struct usb_gadget *gadget = cdev->gadget;
565 struct usb_configuration *c = NULL;
566 int result = -EINVAL;
567 unsigned power = gadget_is_otg(gadget) ? 8 : 100;
571 list_for_each_entry(c, &cdev->configs, list) {
572 if (c->bConfigurationValue == number) {
574 * We disable the FDs of the previous
575 * configuration only if the new configuration
586 } else { /* Zero configuration value - need to reset the config */
592 INFO(cdev, "%s config #%d: %s\n",
593 usb_speed_string(gadget->speed),
594 number, c ? c->label : "unconfigured");
601 /* Initialize all interfaces by setting them to altsetting zero. */
602 for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
603 struct usb_function *f = c->interface[tmp];
604 struct usb_descriptor_header **descriptors;
610 * Record which endpoints are used by the function. This is used
611 * to dispatch control requests targeted at that endpoint to the
612 * function's setup callback instead of the current
613 * configuration's setup callback.
615 switch (gadget->speed) {
616 case USB_SPEED_SUPER:
617 descriptors = f->ss_descriptors;
620 descriptors = f->hs_descriptors;
623 descriptors = f->fs_descriptors;
626 for (; *descriptors; ++descriptors) {
627 struct usb_endpoint_descriptor *ep;
630 if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
633 ep = (struct usb_endpoint_descriptor *)*descriptors;
634 addr = ((ep->bEndpointAddress & 0x80) >> 3)
635 | (ep->bEndpointAddress & 0x0f);
636 set_bit(addr, f->endpoints);
639 result = f->set_alt(f, tmp, 0);
641 DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
642 tmp, f->name, f, result);
648 if (result == USB_GADGET_DELAYED_STATUS) {
650 "%s: interface %d (%s) requested delayed status\n",
651 __func__, tmp, f->name);
652 cdev->delayed_status++;
653 DBG(cdev, "delayed_status count %d\n",
654 cdev->delayed_status);
658 /* when we return, be sure our power usage is valid */
659 power = c->bMaxPower ? (2 * c->bMaxPower) : CONFIG_USB_GADGET_VBUS_DRAW;
661 usb_gadget_vbus_draw(gadget, power);
662 if (result >= 0 && cdev->delayed_status)
663 result = USB_GADGET_DELAYED_STATUS;
668 * usb_add_config() - add a configuration to a device.
669 * @cdev: wraps the USB gadget
670 * @config: the configuration, with bConfigurationValue assigned
671 * @bind: the configuration's bind function
672 * Context: single threaded during gadget setup
674 * One of the main tasks of a composite @bind() routine is to
675 * add each of the configurations it supports, using this routine.
677 * This function returns the value of the configuration's @bind(), which
678 * is zero for success else a negative errno value. Binding configurations
679 * assigns global resources including string IDs, and per-configuration
680 * resources such as interface IDs and endpoints.
682 int usb_add_config(struct usb_composite_dev *cdev,
683 struct usb_configuration *config,
684 int (*bind)(struct usb_configuration *))
686 int status = -EINVAL;
687 struct usb_configuration *c;
689 DBG(cdev, "adding config #%u '%s'/%p\n",
690 config->bConfigurationValue,
691 config->label, config);
693 if (!config->bConfigurationValue || !bind)
696 /* Prevent duplicate configuration identifiers */
697 list_for_each_entry(c, &cdev->configs, list) {
698 if (c->bConfigurationValue == config->bConfigurationValue) {
705 list_add_tail(&config->list, &cdev->configs);
707 INIT_LIST_HEAD(&config->functions);
708 config->next_interface_id = 0;
709 memset(config->interface, 0, sizeof(config->interface));
711 status = bind(config);
713 while (!list_empty(&config->functions)) {
714 struct usb_function *f;
716 f = list_first_entry(&config->functions,
717 struct usb_function, list);
720 DBG(cdev, "unbind function '%s'/%p\n",
722 f->unbind(config, f);
723 /* may free memory for "f" */
726 list_del(&config->list);
731 DBG(cdev, "cfg %d/%p speeds:%s%s%s\n",
732 config->bConfigurationValue, config,
733 config->superspeed ? " super" : "",
734 config->highspeed ? " high" : "",
736 ? (gadget_is_dualspeed(cdev->gadget)
741 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
742 struct usb_function *f = config->interface[i];
746 DBG(cdev, " interface %d = %s/%p\n",
751 /* set_alt(), or next bind(), sets up
752 * ep->driver_data as needed.
754 usb_ep_autoconfig_reset(cdev->gadget);
758 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
759 config->bConfigurationValue, status);
762 EXPORT_SYMBOL_GPL(usb_add_config);
764 static void remove_config(struct usb_composite_dev *cdev,
765 struct usb_configuration *config)
767 while (!list_empty(&config->functions)) {
768 struct usb_function *f;
770 f = list_first_entry(&config->functions,
771 struct usb_function, list);
774 DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
775 f->unbind(config, f);
776 /* may free memory for "f" */
779 list_del(&config->list);
780 if (config->unbind) {
781 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
782 config->unbind(config);
783 /* may free memory for "c" */
788 * usb_remove_config() - remove a configuration from a device.
789 * @cdev: wraps the USB gadget
790 * @config: the configuration
792 * Drivers must call usb_gadget_disconnect before calling this function
793 * to disconnect the device from the host and make sure the host will not
794 * try to enumerate the device while we are changing the config list.
796 void usb_remove_config(struct usb_composite_dev *cdev,
797 struct usb_configuration *config)
801 spin_lock_irqsave(&cdev->lock, flags);
803 if (cdev->config == config)
806 spin_unlock_irqrestore(&cdev->lock, flags);
808 remove_config(cdev, config);
811 /*-------------------------------------------------------------------------*/
813 /* We support strings in multiple languages ... string descriptor zero
814 * says which languages are supported. The typical case will be that
815 * only one language (probably English) is used, with I18N handled on
819 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
821 const struct usb_gadget_strings *s;
827 language = cpu_to_le16(s->language);
828 for (tmp = buf; *tmp && tmp < &buf[126]; tmp++) {
829 if (*tmp == language)
838 static int lookup_string(
839 struct usb_gadget_strings **sp,
845 struct usb_gadget_strings *s;
850 if (s->language != language)
852 value = usb_gadget_get_string(s, id, buf);
859 static int get_string(struct usb_composite_dev *cdev,
860 void *buf, u16 language, int id)
862 struct usb_composite_driver *composite = cdev->driver;
863 struct usb_configuration *c;
864 struct usb_function *f;
867 /* Yes, not only is USB's I18N support probably more than most
868 * folk will ever care about ... also, it's all supported here.
869 * (Except for UTF8 support for Unicode's "Astral Planes".)
872 /* 0 == report all available language codes */
874 struct usb_string_descriptor *s = buf;
875 struct usb_gadget_strings **sp;
878 s->bDescriptorType = USB_DT_STRING;
880 sp = composite->strings;
882 collect_langs(sp, s->wData);
884 list_for_each_entry(c, &cdev->configs, list) {
887 collect_langs(sp, s->wData);
889 list_for_each_entry(f, &c->functions, list) {
892 collect_langs(sp, s->wData);
896 for (len = 0; len <= 126 && s->wData[len]; len++)
901 s->bLength = 2 * (len + 1);
905 /* String IDs are device-scoped, so we look up each string
906 * table we're told about. These lookups are infrequent;
907 * simpler-is-better here.
909 if (composite->strings) {
910 len = lookup_string(composite->strings, buf, language, id);
914 list_for_each_entry(c, &cdev->configs, list) {
916 len = lookup_string(c->strings, buf, language, id);
920 list_for_each_entry(f, &c->functions, list) {
923 len = lookup_string(f->strings, buf, language, id);
932 * usb_string_id() - allocate an unused string ID
933 * @cdev: the device whose string descriptor IDs are being allocated
934 * Context: single threaded during gadget setup
936 * @usb_string_id() is called from bind() callbacks to allocate
937 * string IDs. Drivers for functions, configurations, or gadgets will
938 * then store that ID in the appropriate descriptors and string table.
940 * All string identifier should be allocated using this,
941 * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
942 * that for example different functions don't wrongly assign different
943 * meanings to the same identifier.
945 int usb_string_id(struct usb_composite_dev *cdev)
947 if (cdev->next_string_id < 254) {
948 /* string id 0 is reserved by USB spec for list of
949 * supported languages */
950 /* 255 reserved as well? -- mina86 */
951 cdev->next_string_id++;
952 return cdev->next_string_id;
956 EXPORT_SYMBOL_GPL(usb_string_id);
959 * usb_string_ids() - allocate unused string IDs in batch
960 * @cdev: the device whose string descriptor IDs are being allocated
961 * @str: an array of usb_string objects to assign numbers to
962 * Context: single threaded during gadget setup
964 * @usb_string_ids() is called from bind() callbacks to allocate
965 * string IDs. Drivers for functions, configurations, or gadgets will
966 * then copy IDs from the string table to the appropriate descriptors
967 * and string table for other languages.
969 * All string identifier should be allocated using this,
970 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
971 * example different functions don't wrongly assign different meanings
972 * to the same identifier.
974 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
976 int next = cdev->next_string_id;
978 for (; str->s; ++str) {
979 if (unlikely(next >= 254))
984 cdev->next_string_id = next;
988 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
991 * usb_string_ids_n() - allocate unused string IDs in batch
992 * @c: the device whose string descriptor IDs are being allocated
993 * @n: number of string IDs to allocate
994 * Context: single threaded during gadget setup
996 * Returns the first requested ID. This ID and next @n-1 IDs are now
997 * valid IDs. At least provided that @n is non-zero because if it
998 * is, returns last requested ID which is now very useful information.
1000 * @usb_string_ids_n() is called from bind() callbacks to allocate
1001 * string IDs. Drivers for functions, configurations, or gadgets will
1002 * then store that ID in the appropriate descriptors and string table.
1004 * All string identifier should be allocated using this,
1005 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1006 * example different functions don't wrongly assign different meanings
1007 * to the same identifier.
1009 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1011 unsigned next = c->next_string_id;
1012 if (unlikely(n > 254 || (unsigned)next + n > 254))
1014 c->next_string_id += n;
1017 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1019 /*-------------------------------------------------------------------------*/
1021 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1023 if (req->status || req->actual != req->length)
1024 DBG((struct usb_composite_dev *) ep->driver_data,
1025 "setup complete --> %d, %d/%d\n",
1026 req->status, req->actual, req->length);
1030 * The setup() callback implements all the ep0 functionality that's
1031 * not handled lower down, in hardware or the hardware driver(like
1032 * device and endpoint feature flags, and their status). It's all
1033 * housekeeping for the gadget function we're implementing. Most of
1034 * the work is in config and function specific setup.
1037 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1039 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1040 struct usb_request *req = cdev->req;
1041 int value = -EOPNOTSUPP;
1043 u16 w_index = le16_to_cpu(ctrl->wIndex);
1044 u8 intf = w_index & 0xFF;
1045 u16 w_value = le16_to_cpu(ctrl->wValue);
1046 u16 w_length = le16_to_cpu(ctrl->wLength);
1047 struct usb_function *f = NULL;
1050 /* partial re-init of the response message; the function or the
1051 * gadget might need to intercept e.g. a control-OUT completion
1052 * when we delegate to it.
1055 req->complete = composite_setup_complete;
1057 gadget->ep0->driver_data = cdev;
1059 switch (ctrl->bRequest) {
1061 /* we handle all standard USB descriptors */
1062 case USB_REQ_GET_DESCRIPTOR:
1063 if (ctrl->bRequestType != USB_DIR_IN)
1065 switch (w_value >> 8) {
1068 cdev->desc.bNumConfigurations =
1069 count_configs(cdev, USB_DT_DEVICE);
1070 cdev->desc.bMaxPacketSize0 =
1071 cdev->gadget->ep0->maxpacket;
1072 if (gadget_is_superspeed(gadget)) {
1073 if (gadget->speed >= USB_SPEED_SUPER) {
1074 cdev->desc.bcdUSB = cpu_to_le16(0x0300);
1075 cdev->desc.bMaxPacketSize0 = 9;
1077 cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1081 value = min(w_length, (u16) sizeof cdev->desc);
1082 memcpy(req->buf, &cdev->desc, value);
1084 case USB_DT_DEVICE_QUALIFIER:
1085 if (!gadget_is_dualspeed(gadget) ||
1086 gadget->speed >= USB_SPEED_SUPER)
1089 value = min_t(int, w_length,
1090 sizeof(struct usb_qualifier_descriptor));
1092 case USB_DT_OTHER_SPEED_CONFIG:
1093 if (!gadget_is_dualspeed(gadget) ||
1094 gadget->speed >= USB_SPEED_SUPER)
1098 value = config_desc(cdev, w_value);
1100 value = min(w_length, (u16) value);
1103 value = get_string(cdev, req->buf,
1104 w_index, w_value & 0xff);
1106 value = min(w_length, (u16) value);
1109 if (gadget_is_superspeed(gadget)) {
1110 value = bos_desc(cdev);
1111 value = min(w_length, (u16) value);
1117 /* any number of configs can work */
1118 case USB_REQ_SET_CONFIGURATION:
1119 if (ctrl->bRequestType != 0)
1121 if (gadget_is_otg(gadget)) {
1122 if (gadget->a_hnp_support)
1123 DBG(cdev, "HNP available\n");
1124 else if (gadget->a_alt_hnp_support)
1125 DBG(cdev, "HNP on another port\n");
1127 VDBG(cdev, "HNP inactive\n");
1129 spin_lock(&cdev->lock);
1130 value = set_config(cdev, ctrl, w_value);
1131 spin_unlock(&cdev->lock);
1133 case USB_REQ_GET_CONFIGURATION:
1134 if (ctrl->bRequestType != USB_DIR_IN)
1137 *(u8 *)req->buf = cdev->config->bConfigurationValue;
1139 *(u8 *)req->buf = 0;
1140 value = min(w_length, (u16) 1);
1143 /* function drivers must handle get/set altsetting; if there's
1144 * no get() method, we know only altsetting zero works.
1146 case USB_REQ_SET_INTERFACE:
1147 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1149 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1151 f = cdev->config->interface[intf];
1154 if (w_value && !f->set_alt)
1156 value = f->set_alt(f, w_index, w_value);
1157 if (value == USB_GADGET_DELAYED_STATUS) {
1159 "%s: interface %d (%s) requested delayed status\n",
1160 __func__, intf, f->name);
1161 cdev->delayed_status++;
1162 DBG(cdev, "delayed_status count %d\n",
1163 cdev->delayed_status);
1166 case USB_REQ_GET_INTERFACE:
1167 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1169 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1171 f = cdev->config->interface[intf];
1174 /* lots of interfaces only need altsetting zero... */
1175 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1178 *((u8 *)req->buf) = value;
1179 value = min(w_length, (u16) 1);
1183 * USB 3.0 additions:
1184 * Function driver should handle get_status request. If such cb
1185 * wasn't supplied we respond with default value = 0
1186 * Note: function driver should supply such cb only for the first
1187 * interface of the function
1189 case USB_REQ_GET_STATUS:
1190 if (!gadget_is_superspeed(gadget))
1192 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1194 value = 2; /* This is the length of the get_status reply */
1195 put_unaligned_le16(0, req->buf);
1196 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1198 f = cdev->config->interface[intf];
1201 status = f->get_status ? f->get_status(f) : 0;
1204 put_unaligned_le16(status & 0x0000ffff, req->buf);
1207 * Function drivers should handle SetFeature/ClearFeature
1208 * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1209 * only for the first interface of the function
1211 case USB_REQ_CLEAR_FEATURE:
1212 case USB_REQ_SET_FEATURE:
1213 if (!gadget_is_superspeed(gadget))
1215 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1218 case USB_INTRF_FUNC_SUSPEND:
1219 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1221 f = cdev->config->interface[intf];
1225 if (f->func_suspend)
1226 value = f->func_suspend(f, w_index >> 8);
1229 "func_suspend() returned error %d\n",
1239 "non-core control req%02x.%02x v%04x i%04x l%d\n",
1240 ctrl->bRequestType, ctrl->bRequest,
1241 w_value, w_index, w_length);
1243 /* functions always handle their interfaces and endpoints...
1244 * punt other recipients (other, WUSB, ...) to the current
1245 * configuration code.
1247 * REVISIT it could make sense to let the composite device
1248 * take such requests too, if that's ever needed: to work
1251 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1252 case USB_RECIP_INTERFACE:
1253 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1255 f = cdev->config->interface[intf];
1258 case USB_RECIP_ENDPOINT:
1259 endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
1260 list_for_each_entry(f, &cdev->config->functions, list) {
1261 if (test_bit(endp, f->endpoints))
1264 if (&f->list == &cdev->config->functions)
1270 value = f->setup(f, ctrl);
1272 struct usb_configuration *c;
1276 value = c->setup(c, ctrl);
1282 /* respond with data transfer before status phase? */
1283 if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
1284 req->length = value;
1285 req->zero = value < w_length;
1286 value = usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
1288 DBG(cdev, "ep_queue --> %d\n", value);
1290 composite_setup_complete(gadget->ep0, req);
1292 } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
1294 "%s: Delayed status not supported for w_length != 0",
1299 /* device either stalls (value < 0) or reports success */
1303 static void composite_disconnect(struct usb_gadget *gadget)
1305 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1306 unsigned long flags;
1308 /* REVISIT: should we have config and device level
1309 * disconnect callbacks?
1311 spin_lock_irqsave(&cdev->lock, flags);
1314 if (cdev->driver->disconnect)
1315 cdev->driver->disconnect(cdev);
1316 spin_unlock_irqrestore(&cdev->lock, flags);
1319 /*-------------------------------------------------------------------------*/
1321 static ssize_t composite_show_suspended(struct device *dev,
1322 struct device_attribute *attr,
1325 struct usb_gadget *gadget = dev_to_usb_gadget(dev);
1326 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1328 return sprintf(buf, "%d\n", cdev->suspended);
1331 static DEVICE_ATTR(suspended, 0444, composite_show_suspended, NULL);
1334 composite_unbind(struct usb_gadget *gadget)
1336 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1338 /* composite_disconnect() must already have been called
1339 * by the underlying peripheral controller driver!
1340 * so there's no i/o concurrency that could affect the
1341 * state protected by cdev->lock.
1343 WARN_ON(cdev->config);
1345 while (!list_empty(&cdev->configs)) {
1346 struct usb_configuration *c;
1347 c = list_first_entry(&cdev->configs,
1348 struct usb_configuration, list);
1349 remove_config(cdev, c);
1351 if (cdev->driver->unbind)
1352 cdev->driver->unbind(cdev);
1355 kfree(cdev->req->buf);
1356 usb_ep_free_request(gadget->ep0, cdev->req);
1358 device_remove_file(&gadget->dev, &dev_attr_suspended);
1359 kfree(cdev->def_manufacturer);
1361 set_gadget_data(gadget, NULL);
1364 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
1365 const struct usb_device_descriptor *old)
1375 * these variables may have been set in
1376 * usb_composite_overwrite_options()
1378 idVendor = new->idVendor;
1379 idProduct = new->idProduct;
1380 bcdDevice = new->bcdDevice;
1381 iSerialNumber = new->iSerialNumber;
1382 iManufacturer = new->iManufacturer;
1383 iProduct = new->iProduct;
1387 new->idVendor = idVendor;
1389 new->idProduct = idProduct;
1391 new->bcdDevice = bcdDevice;
1393 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
1395 new->iSerialNumber = iSerialNumber;
1397 new->iManufacturer = iManufacturer;
1399 new->iProduct = iProduct;
1402 static struct usb_composite_driver *to_cdriver(struct usb_gadget_driver *gdrv)
1404 return container_of(gdrv, struct usb_composite_driver, gadget_driver);
1407 static int composite_bind(struct usb_gadget *gadget,
1408 struct usb_gadget_driver *gdriver)
1410 struct usb_composite_dev *cdev;
1411 struct usb_composite_driver *composite = to_cdriver(gdriver);
1412 int status = -ENOMEM;
1414 cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
1418 spin_lock_init(&cdev->lock);
1419 cdev->gadget = gadget;
1420 set_gadget_data(gadget, cdev);
1421 INIT_LIST_HEAD(&cdev->configs);
1423 /* preallocate control response and buffer */
1424 cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
1427 cdev->req->buf = kmalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
1428 if (!cdev->req->buf)
1430 cdev->req->complete = composite_setup_complete;
1431 gadget->ep0->driver_data = cdev;
1433 cdev->driver = composite;
1436 * As per USB compliance update, a device that is actively drawing
1437 * more than 100mA from USB must report itself as bus-powered in
1438 * the GetStatus(DEVICE) call.
1440 if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
1441 usb_gadget_set_selfpowered(gadget);
1443 /* interface and string IDs start at zero via kzalloc.
1444 * we force endpoints to start unassigned; few controller
1445 * drivers will zero ep->driver_data.
1447 usb_ep_autoconfig_reset(cdev->gadget);
1449 /* composite gadget needs to assign strings for whole device (like
1450 * serial number), register function drivers, potentially update
1451 * power state and consumption, etc
1453 status = composite->bind(cdev);
1457 update_unchanged_dev_desc(&cdev->desc, composite->dev);
1459 /* has userspace failed to provide a serial number? */
1460 if (composite->needs_serial && !cdev->desc.iSerialNumber)
1461 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
1464 status = device_create_file(&gadget->dev, &dev_attr_suspended);
1468 INFO(cdev, "%s ready\n", composite->name);
1472 composite_unbind(gadget);
1476 /*-------------------------------------------------------------------------*/
1479 composite_suspend(struct usb_gadget *gadget)
1481 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1482 struct usb_function *f;
1484 /* REVISIT: should we have config level
1485 * suspend/resume callbacks?
1487 DBG(cdev, "suspend\n");
1489 list_for_each_entry(f, &cdev->config->functions, list) {
1494 if (cdev->driver->suspend)
1495 cdev->driver->suspend(cdev);
1497 cdev->suspended = 1;
1499 usb_gadget_vbus_draw(gadget, 2);
1503 composite_resume(struct usb_gadget *gadget)
1505 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1506 struct usb_function *f;
1509 /* REVISIT: should we have config level
1510 * suspend/resume callbacks?
1512 DBG(cdev, "resume\n");
1513 if (cdev->driver->resume)
1514 cdev->driver->resume(cdev);
1516 list_for_each_entry(f, &cdev->config->functions, list) {
1521 maxpower = cdev->config->bMaxPower;
1523 usb_gadget_vbus_draw(gadget, maxpower ?
1524 (2 * maxpower) : CONFIG_USB_GADGET_VBUS_DRAW);
1527 cdev->suspended = 0;
1530 /*-------------------------------------------------------------------------*/
1532 static const struct usb_gadget_driver composite_driver_template = {
1533 .bind = composite_bind,
1534 .unbind = composite_unbind,
1536 .setup = composite_setup,
1537 .disconnect = composite_disconnect,
1539 .suspend = composite_suspend,
1540 .resume = composite_resume,
1543 .owner = THIS_MODULE,
1548 * usb_composite_probe() - register a composite driver
1549 * @driver: the driver to register
1550 * @bind: the callback used to allocate resources that are shared across the
1551 * whole device, such as string IDs, and add its configurations using
1552 * @usb_add_config(). This may fail by returning a negative errno
1553 * value; it should return zero on successful initialization.
1554 * Context: single threaded during gadget setup
1556 * This function is used to register drivers using the composite driver
1557 * framework. The return value is zero, or a negative errno value.
1558 * Those values normally come from the driver's @bind method, which does
1559 * all the work of setting up the driver to match the hardware.
1561 * On successful return, the gadget is ready to respond to requests from
1562 * the host, unless one of its components invokes usb_gadget_disconnect()
1563 * while it was binding. That would usually be done in order to wait for
1564 * some userspace participation.
1566 int usb_composite_probe(struct usb_composite_driver *driver)
1568 struct usb_gadget_driver *gadget_driver;
1570 if (!driver || !driver->dev || !driver->bind)
1574 driver->name = "composite";
1576 driver->gadget_driver = composite_driver_template;
1577 gadget_driver = &driver->gadget_driver;
1579 gadget_driver->function = (char *) driver->name;
1580 gadget_driver->driver.name = driver->name;
1581 gadget_driver->max_speed = driver->max_speed;
1583 return usb_gadget_probe_driver(gadget_driver);
1585 EXPORT_SYMBOL_GPL(usb_composite_probe);
1588 * usb_composite_unregister() - unregister a composite driver
1589 * @driver: the driver to unregister
1591 * This function is used to unregister drivers using the composite
1594 void usb_composite_unregister(struct usb_composite_driver *driver)
1596 usb_gadget_unregister_driver(&driver->gadget_driver);
1598 EXPORT_SYMBOL_GPL(usb_composite_unregister);
1601 * usb_composite_setup_continue() - Continue with the control transfer
1602 * @cdev: the composite device who's control transfer was kept waiting
1604 * This function must be called by the USB function driver to continue
1605 * with the control transfer's data/status stage in case it had requested to
1606 * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
1607 * can request the composite framework to delay the setup request's data/status
1608 * stages by returning USB_GADGET_DELAYED_STATUS.
1610 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
1613 struct usb_request *req = cdev->req;
1614 unsigned long flags;
1616 DBG(cdev, "%s\n", __func__);
1617 spin_lock_irqsave(&cdev->lock, flags);
1619 if (cdev->delayed_status == 0) {
1620 WARN(cdev, "%s: Unexpected call\n", __func__);
1622 } else if (--cdev->delayed_status == 0) {
1623 DBG(cdev, "%s: Completing delayed status\n", __func__);
1625 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1627 DBG(cdev, "ep_queue --> %d\n", value);
1629 composite_setup_complete(cdev->gadget->ep0, req);
1633 spin_unlock_irqrestore(&cdev->lock, flags);
1635 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
1637 static char *composite_default_mfr(struct usb_gadget *gadget)
1642 len = snprintf(NULL, 0, "%s %s with %s", init_utsname()->sysname,
1643 init_utsname()->release, gadget->name);
1645 mfr = kmalloc(len, GFP_KERNEL);
1648 snprintf(mfr, len, "%s %s with %s", init_utsname()->sysname,
1649 init_utsname()->release, gadget->name);
1653 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
1654 struct usb_composite_overwrite *covr)
1656 struct usb_device_descriptor *desc = &cdev->desc;
1657 struct usb_gadget_strings *gstr = cdev->driver->strings[0];
1658 struct usb_string *dev_str = gstr->strings;
1661 desc->idVendor = cpu_to_le16(covr->idVendor);
1663 if (covr->idProduct)
1664 desc->idProduct = cpu_to_le16(covr->idProduct);
1666 if (covr->bcdDevice)
1667 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
1669 if (covr->serial_number) {
1670 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
1671 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
1673 if (covr->manufacturer) {
1674 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
1675 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
1677 } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
1678 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
1679 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
1680 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
1683 if (covr->product) {
1684 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
1685 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
1688 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
1690 MODULE_LICENSE("GPL");
1691 MODULE_AUTHOR("David Brownell");