1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * composite.c - infrastructure for Composite USB Gadgets
4 *
5 * Copyright (C) 2006-2008 David Brownell
6 */
7
8/* #define VERBOSE_DEBUG */
9
10#include <linux/kallsyms.h>
11#include <linux/kernel.h>
12#include <linux/slab.h>
13#include <linux/module.h>
14#include <linux/device.h>
15#include <linux/utsname.h>
16
17#include <linux/usb/composite.h>
18#include <linux/usb/otg.h>
19#include <asm/unaligned.h>
20
21#include "u_os_desc.h"
22
23/**
24 * struct usb_os_string - represents OS String to be reported by a gadget
25 * @bLength: total length of the entire descritor, always 0x12
26 * @bDescriptorType: USB_DT_STRING
27 * @qwSignature: the OS String proper
28 * @bMS_VendorCode: code used by the host for subsequent requests
29 * @bPad: not used, must be zero
30 */
31struct usb_os_string {
32	__u8	bLength;
33	__u8	bDescriptorType;
34	__u8	qwSignature[OS_STRING_QW_SIGN_LEN];
35	__u8	bMS_VendorCode;
36	__u8	bPad;
37} __packed;
38
39/*
40 * The code in this file is utility code, used to build a gadget driver
41 * from one or more "function" drivers, one or more "configuration"
42 * objects, and a "usb_composite_driver" by gluing them together along
43 * with the relevant device-wide data.
44 */
45
46static struct usb_gadget_strings **get_containers_gs(
47		struct usb_gadget_string_container *uc)
48{
49	return (struct usb_gadget_strings **)uc->stash;
50}
51
52/**
53 * function_descriptors() - get function descriptors for speed
54 * @f: the function
55 * @speed: the speed
56 *
57 * Returns the descriptors or NULL if not set.
58 */
59static struct usb_descriptor_header **
60function_descriptors(struct usb_function *f,
61		     enum usb_device_speed speed)
62{
63	struct usb_descriptor_header **descriptors;
64
65	/*
66	 * NOTE: we try to help gadget drivers which might not be setting
67	 * max_speed appropriately.
68	 */
69
70	switch (speed) {
71	case USB_SPEED_SUPER_PLUS:
72		descriptors = f->ssp_descriptors;
73		if (descriptors)
74			break;
75		fallthrough;
76	case USB_SPEED_SUPER:
77		descriptors = f->ss_descriptors;
78		if (descriptors)
79			break;
80		fallthrough;
81	case USB_SPEED_HIGH:
82		descriptors = f->hs_descriptors;
83		if (descriptors)
84			break;
85		fallthrough;
86	default:
87		descriptors = f->fs_descriptors;
88	}
89
90	/*
91	 * if we can't find any descriptors at all, then this gadget deserves to
92	 * Oops with a NULL pointer dereference
93	 */
94
95	return descriptors;
96}
97
98/**
99 * next_desc() - advance to the next desc_type descriptor
100 * @t: currect pointer within descriptor array
101 * @desc_type: descriptor type
102 *
103 * Return: next desc_type descriptor or NULL
104 *
105 * Iterate over @t until either desc_type descriptor found or
106 * NULL (that indicates end of list) encountered
107 */
108static struct usb_descriptor_header**
109next_desc(struct usb_descriptor_header **t, u8 desc_type)
110{
111	for (; *t; t++) {
112		if ((*t)->bDescriptorType == desc_type)
113			return t;
114	}
115	return NULL;
116}
117
118/*
119 * for_each_desc() - iterate over desc_type descriptors in the
120 * descriptors list
121 * @start: pointer within descriptor array.
122 * @iter_desc: desc_type descriptor to use as the loop cursor
123 * @desc_type: wanted descriptr type
124 */
125#define for_each_desc(start, iter_desc, desc_type) \
126	for (iter_desc = next_desc(start, desc_type); \
127	     iter_desc; iter_desc = next_desc(iter_desc + 1, desc_type))
128
129/**
130 * config_ep_by_speed_and_alt() - configures the given endpoint
131 * according to gadget speed.
132 * @g: pointer to the gadget
133 * @f: usb function
134 * @_ep: the endpoint to configure
135 * @alt: alternate setting number
136 *
137 * Return: error code, 0 on success
138 *
139 * This function chooses the right descriptors for a given
140 * endpoint according to gadget speed and saves it in the
141 * endpoint desc field. If the endpoint already has a descriptor
142 * assigned to it - overwrites it with currently corresponding
143 * descriptor. The endpoint maxpacket field is updated according
144 * to the chosen descriptor.
145 * Note: the supplied function should hold all the descriptors
146 * for supported speeds
147 */
148int config_ep_by_speed_and_alt(struct usb_gadget *g,
149				struct usb_function *f,
150				struct usb_ep *_ep,
151				u8 alt)
152{
153	struct usb_endpoint_descriptor *chosen_desc = NULL;
154	struct usb_interface_descriptor *int_desc = NULL;
155	struct usb_descriptor_header **speed_desc = NULL;
156
157	struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
158	int want_comp_desc = 0;
159
160	struct usb_descriptor_header **d_spd; /* cursor for speed desc */
161
162	if (!g || !f || !_ep)
163		return -EIO;
164
165	/* select desired speed */
166	switch (g->speed) {
167	case USB_SPEED_SUPER_PLUS:
168		if (gadget_is_superspeed_plus(g)) {
169			speed_desc = f->ssp_descriptors;
170			want_comp_desc = 1;
171			break;
172		}
173		fallthrough;
174	case USB_SPEED_SUPER:
175		if (gadget_is_superspeed(g)) {
176			speed_desc = f->ss_descriptors;
177			want_comp_desc = 1;
178			break;
179		}
180		fallthrough;
181	case USB_SPEED_HIGH:
182		if (gadget_is_dualspeed(g)) {
183			speed_desc = f->hs_descriptors;
184			break;
185		}
186		fallthrough;
187	default:
188		speed_desc = f->fs_descriptors;
189	}
190
191	/* find correct alternate setting descriptor */
192	for_each_desc(speed_desc, d_spd, USB_DT_INTERFACE) {
193		int_desc = (struct usb_interface_descriptor *)*d_spd;
194
195		if (int_desc->bAlternateSetting == alt) {
196			speed_desc = d_spd;
197			goto intf_found;
198		}
199	}
200	return -EIO;
201
202intf_found:
203	/* find descriptors */
204	for_each_desc(speed_desc, d_spd, USB_DT_ENDPOINT) {
205		chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
206		if (chosen_desc->bEndpointAddress == _ep->address)
207			goto ep_found;
208	}
209	return -EIO;
210
211ep_found:
212	/* commit results */
213	_ep->maxpacket = usb_endpoint_maxp(chosen_desc);
214	_ep->desc = chosen_desc;
215	_ep->comp_desc = NULL;
216	_ep->maxburst = 0;
217	_ep->mult = 1;
218
219	if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
220				usb_endpoint_xfer_int(_ep->desc)))
221		_ep->mult = usb_endpoint_maxp_mult(_ep->desc);
222
223	if (!want_comp_desc)
224		return 0;
225
226	/*
227	 * Companion descriptor should follow EP descriptor
228	 * USB 3.0 spec, #9.6.7
229	 */
230	comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
231	if (!comp_desc ||
232	    (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
233		return -EIO;
234	_ep->comp_desc = comp_desc;
235	if (g->speed >= USB_SPEED_SUPER) {
236		switch (usb_endpoint_type(_ep->desc)) {
237		case USB_ENDPOINT_XFER_ISOC:
238			/* mult: bits 1:0 of bmAttributes */
239			_ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
240			fallthrough;
241		case USB_ENDPOINT_XFER_BULK:
242		case USB_ENDPOINT_XFER_INT:
243			_ep->maxburst = comp_desc->bMaxBurst + 1;
244			break;
245		default:
246			if (comp_desc->bMaxBurst != 0) {
247				struct usb_composite_dev *cdev;
248
249				cdev = get_gadget_data(g);
250				ERROR(cdev, "ep0 bMaxBurst must be 0\n");
251			}
252			_ep->maxburst = 1;
253			break;
254		}
255	}
256	return 0;
257}
258EXPORT_SYMBOL_GPL(config_ep_by_speed_and_alt);
259
260/**
261 * config_ep_by_speed() - configures the given endpoint
262 * according to gadget speed.
263 * @g: pointer to the gadget
264 * @f: usb function
265 * @_ep: the endpoint to configure
266 *
267 * Return: error code, 0 on success
268 *
269 * This function chooses the right descriptors for a given
270 * endpoint according to gadget speed and saves it in the
271 * endpoint desc field. If the endpoint already has a descriptor
272 * assigned to it - overwrites it with currently corresponding
273 * descriptor. The endpoint maxpacket field is updated according
274 * to the chosen descriptor.
275 * Note: the supplied function should hold all the descriptors
276 * for supported speeds
277 */
278int config_ep_by_speed(struct usb_gadget *g,
279			struct usb_function *f,
280			struct usb_ep *_ep)
281{
282	return config_ep_by_speed_and_alt(g, f, _ep, 0);
283}
284EXPORT_SYMBOL_GPL(config_ep_by_speed);
285
286/**
287 * usb_add_function() - add a function to a configuration
288 * @config: the configuration
289 * @function: the function being added
290 * Context: single threaded during gadget setup
291 *
292 * After initialization, each configuration must have one or more
293 * functions added to it.  Adding a function involves calling its @bind()
294 * method to allocate resources such as interface and string identifiers
295 * and endpoints.
296 *
297 * This function returns the value of the function's bind(), which is
298 * zero for success else a negative errno value.
299 */
300int usb_add_function(struct usb_configuration *config,
301		struct usb_function *function)
302{
303	int	value = -EINVAL;
304
305	DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
306			function->name, function,
307			config->label, config);
308
309	if (!function->set_alt || !function->disable)
310		goto done;
311
312	function->config = config;
313	list_add_tail(&function->list, &config->functions);
314
315	if (function->bind_deactivated) {
316		value = usb_function_deactivate(function);
317		if (value)
318			goto done;
319	}
320
321	/* REVISIT *require* function->bind? */
322	if (function->bind) {
323		value = function->bind(config, function);
324		if (value < 0) {
325			list_del(&function->list);
326			function->config = NULL;
327		}
328	} else
329		value = 0;
330
331	/* We allow configurations that don't work at both speeds.
332	 * If we run into a lowspeed Linux system, treat it the same
333	 * as full speed ... it's the function drivers that will need
334	 * to avoid bulk and ISO transfers.
335	 */
336	if (!config->fullspeed && function->fs_descriptors)
337		config->fullspeed = true;
338	if (!config->highspeed && function->hs_descriptors)
339		config->highspeed = true;
340	if (!config->superspeed && function->ss_descriptors)
341		config->superspeed = true;
342	if (!config->superspeed_plus && function->ssp_descriptors)
343		config->superspeed_plus = true;
344
345done:
346	if (value)
347		DBG(config->cdev, "adding '%s'/%p --> %d\n",
348				function->name, function, value);
349	return value;
350}
351EXPORT_SYMBOL_GPL(usb_add_function);
352
353void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
354{
355	if (f->disable)
356		f->disable(f);
357
358	bitmap_zero(f->endpoints, 32);
359	list_del(&f->list);
360	if (f->unbind)
361		f->unbind(c, f);
362
363	if (f->bind_deactivated)
364		usb_function_activate(f);
365}
366EXPORT_SYMBOL_GPL(usb_remove_function);
367
368/**
369 * usb_function_deactivate - prevent function and gadget enumeration
370 * @function: the function that isn't yet ready to respond
371 *
372 * Blocks response of the gadget driver to host enumeration by
373 * preventing the data line pullup from being activated.  This is
374 * normally called during @bind() processing to change from the
375 * initial "ready to respond" state, or when a required resource
376 * becomes available.
377 *
378 * For example, drivers that serve as a passthrough to a userspace
379 * daemon can block enumeration unless that daemon (such as an OBEX,
380 * MTP, or print server) is ready to handle host requests.
381 *
382 * Not all systems support software control of their USB peripheral
383 * data pullups.
384 *
385 * Returns zero on success, else negative errno.
386 */
387int usb_function_deactivate(struct usb_function *function)
388{
389	struct usb_composite_dev	*cdev = function->config->cdev;
390	unsigned long			flags;
391	int				status = 0;
392
393	spin_lock_irqsave(&cdev->lock, flags);
394
395	if (cdev->deactivations == 0) {
396		spin_unlock_irqrestore(&cdev->lock, flags);
397		status = usb_gadget_deactivate(cdev->gadget);
398		spin_lock_irqsave(&cdev->lock, flags);
399	}
400	if (status == 0)
401		cdev->deactivations++;
402
403	spin_unlock_irqrestore(&cdev->lock, flags);
404	return status;
405}
406EXPORT_SYMBOL_GPL(usb_function_deactivate);
407
408/**
409 * usb_function_activate - allow function and gadget enumeration
410 * @function: function on which usb_function_activate() was called
411 *
412 * Reverses effect of usb_function_deactivate().  If no more functions
413 * are delaying their activation, the gadget driver will respond to
414 * host enumeration procedures.
415 *
416 * Returns zero on success, else negative errno.
417 */
418int usb_function_activate(struct usb_function *function)
419{
420	struct usb_composite_dev	*cdev = function->config->cdev;
421	unsigned long			flags;
422	int				status = 0;
423
424	spin_lock_irqsave(&cdev->lock, flags);
425
426	if (WARN_ON(cdev->deactivations == 0))
427		status = -EINVAL;
428	else {
429		cdev->deactivations--;
430		if (cdev->deactivations == 0) {
431			spin_unlock_irqrestore(&cdev->lock, flags);
432			status = usb_gadget_activate(cdev->gadget);
433			spin_lock_irqsave(&cdev->lock, flags);
434		}
435	}
436
437	spin_unlock_irqrestore(&cdev->lock, flags);
438	return status;
439}
440EXPORT_SYMBOL_GPL(usb_function_activate);
441
442/**
443 * usb_interface_id() - allocate an unused interface ID
444 * @config: configuration associated with the interface
445 * @function: function handling the interface
446 * Context: single threaded during gadget setup
447 *
448 * usb_interface_id() is called from usb_function.bind() callbacks to
449 * allocate new interface IDs.  The function driver will then store that
450 * ID in interface, association, CDC union, and other descriptors.  It
451 * will also handle any control requests targeted at that interface,
452 * particularly changing its altsetting via set_alt().  There may
453 * also be class-specific or vendor-specific requests to handle.
454 *
455 * All interface identifier should be allocated using this routine, to
456 * ensure that for example different functions don't wrongly assign
457 * different meanings to the same identifier.  Note that since interface
458 * identifiers are configuration-specific, functions used in more than
459 * one configuration (or more than once in a given configuration) need
460 * multiple versions of the relevant descriptors.
461 *
462 * Returns the interface ID which was allocated; or -ENODEV if no
463 * more interface IDs can be allocated.
464 */
465int usb_interface_id(struct usb_configuration *config,
466		struct usb_function *function)
467{
468	unsigned id = config->next_interface_id;
469
470	if (id < MAX_CONFIG_INTERFACES) {
471		config->interface[id] = function;
472		config->next_interface_id = id + 1;
473		return id;
474	}
475	return -ENODEV;
476}
477EXPORT_SYMBOL_GPL(usb_interface_id);
478
479static u8 encode_bMaxPower(enum usb_device_speed speed,
480		struct usb_configuration *c)
481{
482	unsigned val;
483
484	if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
485		val = c->MaxPower;
486	else
487		val = CONFIG_USB_GADGET_VBUS_DRAW;
488	if (!val)
489		return 0;
490	if (speed < USB_SPEED_SUPER)
491		return min(val, 500U) / 2;
492	else
493		/*
494		 * USB 3.x supports up to 900mA, but since 900 isn't divisible
495		 * by 8 the integral division will effectively cap to 896mA.
496		 */
497		return min(val, 900U) / 8;
498}
499
500static int config_buf(struct usb_configuration *config,
501		enum usb_device_speed speed, void *buf, u8 type)
502{
503	struct usb_config_descriptor	*c = buf;
504	void				*next = buf + USB_DT_CONFIG_SIZE;
505	int				len;
506	struct usb_function		*f;
507	int				status;
508
509	len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
510	/* write the config descriptor */
511	c = buf;
512	c->bLength = USB_DT_CONFIG_SIZE;
513	c->bDescriptorType = type;
514	/* wTotalLength is written later */
515	c->bNumInterfaces = config->next_interface_id;
516	c->bConfigurationValue = config->bConfigurationValue;
517	c->iConfiguration = config->iConfiguration;
518	c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
519	c->bMaxPower = encode_bMaxPower(speed, config);
520
521	/* There may be e.g. OTG descriptors */
522	if (config->descriptors) {
523		status = usb_descriptor_fillbuf(next, len,
524				config->descriptors);
525		if (status < 0)
526			return status;
527		len -= status;
528		next += status;
529	}
530
531	/* add each function's descriptors */
532	list_for_each_entry(f, &config->functions, list) {
533		struct usb_descriptor_header **descriptors;
534
535		descriptors = function_descriptors(f, speed);
536		if (!descriptors)
537			continue;
538		status = usb_descriptor_fillbuf(next, len,
539			(const struct usb_descriptor_header **) descriptors);
540		if (status < 0)
541			return status;
542		len -= status;
543		next += status;
544	}
545
546	len = next - buf;
547	c->wTotalLength = cpu_to_le16(len);
548	return len;
549}
550
551static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
552{
553	struct usb_gadget		*gadget = cdev->gadget;
554	struct usb_configuration	*c;
555	struct list_head		*pos;
556	u8				type = w_value >> 8;
557	enum usb_device_speed		speed = USB_SPEED_UNKNOWN;
558
559	if (gadget->speed >= USB_SPEED_SUPER)
560		speed = gadget->speed;
561	else if (gadget_is_dualspeed(gadget)) {
562		int	hs = 0;
563		if (gadget->speed == USB_SPEED_HIGH)
564			hs = 1;
565		if (type == USB_DT_OTHER_SPEED_CONFIG)
566			hs = !hs;
567		if (hs)
568			speed = USB_SPEED_HIGH;
569
570	}
571
572	/* This is a lookup by config *INDEX* */
573	w_value &= 0xff;
574
575	pos = &cdev->configs;
576	c = cdev->os_desc_config;
577	if (c)
578		goto check_config;
579
580	while ((pos = pos->next) !=  &cdev->configs) {
581		c = list_entry(pos, typeof(*c), list);
582
583		/* skip OS Descriptors config which is handled separately */
584		if (c == cdev->os_desc_config)
585			continue;
586
587check_config:
588		/* ignore configs that won't work at this speed */
589		switch (speed) {
590		case USB_SPEED_SUPER_PLUS:
591			if (!c->superspeed_plus)
592				continue;
593			break;
594		case USB_SPEED_SUPER:
595			if (!c->superspeed)
596				continue;
597			break;
598		case USB_SPEED_HIGH:
599			if (!c->highspeed)
600				continue;
601			break;
602		default:
603			if (!c->fullspeed)
604				continue;
605		}
606
607		if (w_value == 0)
608			return config_buf(c, speed, cdev->req->buf, type);
609		w_value--;
610	}
611	return -EINVAL;
612}
613
614static int count_configs(struct usb_composite_dev *cdev, unsigned type)
615{
616	struct usb_gadget		*gadget = cdev->gadget;
617	struct usb_configuration	*c;
618	unsigned			count = 0;
619	int				hs = 0;
620	int				ss = 0;
621	int				ssp = 0;
622
623	if (gadget_is_dualspeed(gadget)) {
624		if (gadget->speed == USB_SPEED_HIGH)
625			hs = 1;
626		if (gadget->speed == USB_SPEED_SUPER)
627			ss = 1;
628		if (gadget->speed == USB_SPEED_SUPER_PLUS)
629			ssp = 1;
630		if (type == USB_DT_DEVICE_QUALIFIER)
631			hs = !hs;
632	}
633	list_for_each_entry(c, &cdev->configs, list) {
634		/* ignore configs that won't work at this speed */
635		if (ssp) {
636			if (!c->superspeed_plus)
637				continue;
638		} else if (ss) {
639			if (!c->superspeed)
640				continue;
641		} else if (hs) {
642			if (!c->highspeed)
643				continue;
644		} else {
645			if (!c->fullspeed)
646				continue;
647		}
648		count++;
649	}
650	return count;
651}
652
653/**
654 * bos_desc() - prepares the BOS descriptor.
655 * @cdev: pointer to usb_composite device to generate the bos
656 *	descriptor for
657 *
658 * This function generates the BOS (Binary Device Object)
659 * descriptor and its device capabilities descriptors. The BOS
660 * descriptor should be supported by a SuperSpeed device.
661 */
662static int bos_desc(struct usb_composite_dev *cdev)
663{
664	struct usb_ext_cap_descriptor	*usb_ext;
665	struct usb_dcd_config_params	dcd_config_params;
666	struct usb_bos_descriptor	*bos = cdev->req->buf;
667	unsigned int			besl = 0;
668
669	bos->bLength = USB_DT_BOS_SIZE;
670	bos->bDescriptorType = USB_DT_BOS;
671
672	bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
673	bos->bNumDeviceCaps = 0;
674
675	/* Get Controller configuration */
676	if (cdev->gadget->ops->get_config_params) {
677		cdev->gadget->ops->get_config_params(cdev->gadget,
678						     &dcd_config_params);
679	} else {
680		dcd_config_params.besl_baseline =
681			USB_DEFAULT_BESL_UNSPECIFIED;
682		dcd_config_params.besl_deep =
683			USB_DEFAULT_BESL_UNSPECIFIED;
684		dcd_config_params.bU1devExitLat =
685			USB_DEFAULT_U1_DEV_EXIT_LAT;
686		dcd_config_params.bU2DevExitLat =
687			cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
688	}
689
690	if (dcd_config_params.besl_baseline != USB_DEFAULT_BESL_UNSPECIFIED)
691		besl = USB_BESL_BASELINE_VALID |
692			USB_SET_BESL_BASELINE(dcd_config_params.besl_baseline);
693
694	if (dcd_config_params.besl_deep != USB_DEFAULT_BESL_UNSPECIFIED)
695		besl |= USB_BESL_DEEP_VALID |
696			USB_SET_BESL_DEEP(dcd_config_params.besl_deep);
697
698	/*
699	 * A SuperSpeed device shall include the USB2.0 extension descriptor
700	 * and shall support LPM when operating in USB2.0 HS mode.
701	 */
702	usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
703	bos->bNumDeviceCaps++;
704	le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
705	usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
706	usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
707	usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
708	usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
709					    USB_BESL_SUPPORT | besl);
710
711	/*
712	 * The Superspeed USB Capability descriptor shall be implemented by all
713	 * SuperSpeed devices.
714	 */
715	if (gadget_is_superspeed(cdev->gadget)) {
716		struct usb_ss_cap_descriptor *ss_cap;
717
718		ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
719		bos->bNumDeviceCaps++;
720		le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
721		ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
722		ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
723		ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
724		ss_cap->bmAttributes = 0; /* LTM is not supported yet */
725		ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
726						      USB_FULL_SPEED_OPERATION |
727						      USB_HIGH_SPEED_OPERATION |
728						      USB_5GBPS_OPERATION);
729		ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
730		ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
731		ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
732	}
733
734	/* The SuperSpeedPlus USB Device Capability descriptor */
735	if (gadget_is_superspeed_plus(cdev->gadget)) {
736		struct usb_ssp_cap_descriptor *ssp_cap;
737
738		ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
739		bos->bNumDeviceCaps++;
740
741		/*
742		 * Report typical values.
743		 */
744
745		le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(1));
746		ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(1);
747		ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
748		ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
749		ssp_cap->bReserved = 0;
750		ssp_cap->wReserved = 0;
751
752		/* SSAC = 1 (2 attributes) */
753		ssp_cap->bmAttributes = cpu_to_le32(1);
754
755		/* Min RX/TX Lane Count = 1 */
756		ssp_cap->wFunctionalitySupport =
757			cpu_to_le16((1 << 8) | (1 << 12));
758
759		/*
760		 * bmSublinkSpeedAttr[0]:
761		 *   ST  = Symmetric, RX
762		 *   LSE =  3 (Gbps)
763		 *   LP  =  1 (SuperSpeedPlus)
764		 *   LSM = 10 (10 Gbps)
765		 */
766		ssp_cap->bmSublinkSpeedAttr[0] =
767			cpu_to_le32((3 << 4) | (1 << 14) | (0xa << 16));
768		/*
769		 * bmSublinkSpeedAttr[1] =
770		 *   ST  = Symmetric, TX
771		 *   LSE =  3 (Gbps)
772		 *   LP  =  1 (SuperSpeedPlus)
773		 *   LSM = 10 (10 Gbps)
774		 */
775		ssp_cap->bmSublinkSpeedAttr[1] =
776			cpu_to_le32((3 << 4) | (1 << 14) |
777				    (0xa << 16) | (1 << 7));
778	}
779
780	return le16_to_cpu(bos->wTotalLength);
781}
782
783static void device_qual(struct usb_composite_dev *cdev)
784{
785	struct usb_qualifier_descriptor	*qual = cdev->req->buf;
786
787	qual->bLength = sizeof(*qual);
788	qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
789	/* POLICY: same bcdUSB and device type info at both speeds */
790	qual->bcdUSB = cdev->desc.bcdUSB;
791	qual->bDeviceClass = cdev->desc.bDeviceClass;
792	qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
793	qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
794	/* ASSUME same EP0 fifo size at both speeds */
795	qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
796	qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
797	qual->bRESERVED = 0;
798}
799
800/*-------------------------------------------------------------------------*/
801
802static void reset_config(struct usb_composite_dev *cdev)
803{
804	struct usb_function		*f;
805
806	DBG(cdev, "reset config\n");
807
808	list_for_each_entry(f, &cdev->config->functions, list) {
809		if (f->disable)
810			f->disable(f);
811
812		bitmap_zero(f->endpoints, 32);
813	}
814	cdev->config = NULL;
815	cdev->delayed_status = 0;
816}
817
818static int set_config(struct usb_composite_dev *cdev,
819		const struct usb_ctrlrequest *ctrl, unsigned number)
820{
821	struct usb_gadget	*gadget = cdev->gadget;
822	struct usb_configuration *c = NULL;
823	int			result = -EINVAL;
824	unsigned		power = gadget_is_otg(gadget) ? 8 : 100;
825	int			tmp;
826
827	if (number) {
828		list_for_each_entry(c, &cdev->configs, list) {
829			if (c->bConfigurationValue == number) {
830				/*
831				 * We disable the FDs of the previous
832				 * configuration only if the new configuration
833				 * is a valid one
834				 */
835				if (cdev->config)
836					reset_config(cdev);
837				result = 0;
838				break;
839			}
840		}
841		if (result < 0)
842			goto done;
843	} else { /* Zero configuration value - need to reset the config */
844		if (cdev->config)
845			reset_config(cdev);
846		result = 0;
847	}
848
849	DBG(cdev, "%s config #%d: %s\n",
850	    usb_speed_string(gadget->speed),
851	    number, c ? c->label : "unconfigured");
852
853	if (!c)
854		goto done;
855
856	usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
857	cdev->config = c;
858
859	/* Initialize all interfaces by setting them to altsetting zero. */
860	for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
861		struct usb_function	*f = c->interface[tmp];
862		struct usb_descriptor_header **descriptors;
863
864		if (!f)
865			break;
866
867		/*
868		 * Record which endpoints are used by the function. This is used
869		 * to dispatch control requests targeted at that endpoint to the
870		 * function's setup callback instead of the current
871		 * configuration's setup callback.
872		 */
873		descriptors = function_descriptors(f, gadget->speed);
874
875		for (; *descriptors; ++descriptors) {
876			struct usb_endpoint_descriptor *ep;
877			int addr;
878
879			if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
880				continue;
881
882			ep = (struct usb_endpoint_descriptor *)*descriptors;
883			addr = ((ep->bEndpointAddress & 0x80) >> 3)
884			     |  (ep->bEndpointAddress & 0x0f);
885			set_bit(addr, f->endpoints);
886		}
887
888		result = f->set_alt(f, tmp, 0);
889		if (result < 0) {
890			DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
891					tmp, f->name, f, result);
892
893			reset_config(cdev);
894			goto done;
895		}
896
897		if (result == USB_GADGET_DELAYED_STATUS) {
898			DBG(cdev,
899			 "%s: interface %d (%s) requested delayed status\n",
900					__func__, tmp, f->name);
901			cdev->delayed_status++;
902			DBG(cdev, "delayed_status count %d\n",
903					cdev->delayed_status);
904		}
905	}
906
907	/* when we return, be sure our power usage is valid */
908	if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
909		power = c->MaxPower;
910	else
911		power = CONFIG_USB_GADGET_VBUS_DRAW;
912
913	if (gadget->speed < USB_SPEED_SUPER)
914		power = min(power, 500U);
915	else
916		power = min(power, 900U);
917done:
918	if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
919		usb_gadget_set_selfpowered(gadget);
920	else
921		usb_gadget_clear_selfpowered(gadget);
922
923	usb_gadget_vbus_draw(gadget, power);
924	if (result >= 0 && cdev->delayed_status)
925		result = USB_GADGET_DELAYED_STATUS;
926	return result;
927}
928
929int usb_add_config_only(struct usb_composite_dev *cdev,
930		struct usb_configuration *config)
931{
932	struct usb_configuration *c;
933
934	if (!config->bConfigurationValue)
935		return -EINVAL;
936
937	/* Prevent duplicate configuration identifiers */
938	list_for_each_entry(c, &cdev->configs, list) {
939		if (c->bConfigurationValue == config->bConfigurationValue)
940			return -EBUSY;
941	}
942
943	config->cdev = cdev;
944	list_add_tail(&config->list, &cdev->configs);
945
946	INIT_LIST_HEAD(&config->functions);
947	config->next_interface_id = 0;
948	memset(config->interface, 0, sizeof(config->interface));
949
950	return 0;
951}
952EXPORT_SYMBOL_GPL(usb_add_config_only);
953
954/**
955 * usb_add_config() - add a configuration to a device.
956 * @cdev: wraps the USB gadget
957 * @config: the configuration, with bConfigurationValue assigned
958 * @bind: the configuration's bind function
959 * Context: single threaded during gadget setup
960 *
961 * One of the main tasks of a composite @bind() routine is to
962 * add each of the configurations it supports, using this routine.
963 *
964 * This function returns the value of the configuration's @bind(), which
965 * is zero for success else a negative errno value.  Binding configurations
966 * assigns global resources including string IDs, and per-configuration
967 * resources such as interface IDs and endpoints.
968 */
969int usb_add_config(struct usb_composite_dev *cdev,
970		struct usb_configuration *config,
971		int (*bind)(struct usb_configuration *))
972{
973	int				status = -EINVAL;
974
975	if (!bind)
976		goto done;
977
978	DBG(cdev, "adding config #%u '%s'/%p\n",
979			config->bConfigurationValue,
980			config->label, config);
981
982	status = usb_add_config_only(cdev, config);
983	if (status)
984		goto done;
985
986	status = bind(config);
987	if (status < 0) {
988		while (!list_empty(&config->functions)) {
989			struct usb_function		*f;
990
991			f = list_first_entry(&config->functions,
992					struct usb_function, list);
993			list_del(&f->list);
994			if (f->unbind) {
995				DBG(cdev, "unbind function '%s'/%p\n",
996					f->name, f);
997				f->unbind(config, f);
998				/* may free memory for "f" */
999			}
1000		}
1001		list_del(&config->list);
1002		config->cdev = NULL;
1003	} else {
1004		unsigned	i;
1005
1006		DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
1007			config->bConfigurationValue, config,
1008			config->superspeed_plus ? " superplus" : "",
1009			config->superspeed ? " super" : "",
1010			config->highspeed ? " high" : "",
1011			config->fullspeed
1012				? (gadget_is_dualspeed(cdev->gadget)
1013					? " full"
1014					: " full/low")
1015				: "");
1016
1017		for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
1018			struct usb_function	*f = config->interface[i];
1019
1020			if (!f)
1021				continue;
1022			DBG(cdev, "  interface %d = %s/%p\n",
1023				i, f->name, f);
1024		}
1025	}
1026
1027	/* set_alt(), or next bind(), sets up ep->claimed as needed */
1028	usb_ep_autoconfig_reset(cdev->gadget);
1029
1030done:
1031	if (status)
1032		DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
1033				config->bConfigurationValue, status);
1034	return status;
1035}
1036EXPORT_SYMBOL_GPL(usb_add_config);
1037
1038static void remove_config(struct usb_composite_dev *cdev,
1039			      struct usb_configuration *config)
1040{
1041	while (!list_empty(&config->functions)) {
1042		struct usb_function		*f;
1043
1044		f = list_first_entry(&config->functions,
1045				struct usb_function, list);
1046
1047		usb_remove_function(config, f);
1048	}
1049	list_del(&config->list);
1050	if (config->unbind) {
1051		DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
1052		config->unbind(config);
1053			/* may free memory for "c" */
1054	}
1055}
1056
1057/**
1058 * usb_remove_config() - remove a configuration from a device.
1059 * @cdev: wraps the USB gadget
1060 * @config: the configuration
1061 *
1062 * Drivers must call usb_gadget_disconnect before calling this function
1063 * to disconnect the device from the host and make sure the host will not
1064 * try to enumerate the device while we are changing the config list.
1065 */
1066void usb_remove_config(struct usb_composite_dev *cdev,
1067		      struct usb_configuration *config)
1068{
1069	unsigned long flags;
1070
1071	spin_lock_irqsave(&cdev->lock, flags);
1072
1073	if (cdev->config == config)
1074		reset_config(cdev);
1075
1076	spin_unlock_irqrestore(&cdev->lock, flags);
1077
1078	remove_config(cdev, config);
1079}
1080
1081/*-------------------------------------------------------------------------*/
1082
1083/* We support strings in multiple languages ... string descriptor zero
1084 * says which languages are supported.  The typical case will be that
1085 * only one language (probably English) is used, with i18n handled on
1086 * the host side.
1087 */
1088
1089static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1090{
1091	const struct usb_gadget_strings	*s;
1092	__le16				language;
1093	__le16				*tmp;
1094
1095	while (*sp) {
1096		s = *sp;
1097		language = cpu_to_le16(s->language);
1098		for (tmp = buf; *tmp && tmp < &buf[USB_MAX_STRING_LEN]; tmp++) {
1099			if (*tmp == language)
1100				goto repeat;
1101		}
1102		*tmp++ = language;
1103repeat:
1104		sp++;
1105	}
1106}
1107
1108static int lookup_string(
1109	struct usb_gadget_strings	**sp,
1110	void				*buf,
1111	u16				language,
1112	int				id
1113)
1114{
1115	struct usb_gadget_strings	*s;
1116	int				value;
1117
1118	while (*sp) {
1119		s = *sp++;
1120		if (s->language != language)
1121			continue;
1122		value = usb_gadget_get_string(s, id, buf);
1123		if (value > 0)
1124			return value;
1125	}
1126	return -EINVAL;
1127}
1128
1129static int get_string(struct usb_composite_dev *cdev,
1130		void *buf, u16 language, int id)
1131{
1132	struct usb_composite_driver	*composite = cdev->driver;
1133	struct usb_gadget_string_container *uc;
1134	struct usb_configuration	*c;
1135	struct usb_function		*f;
1136	int				len;
1137
1138	/* Yes, not only is USB's i18n support probably more than most
1139	 * folk will ever care about ... also, it's all supported here.
1140	 * (Except for UTF8 support for Unicode's "Astral Planes".)
1141	 */
1142
1143	/* 0 == report all available language codes */
1144	if (id == 0) {
1145		struct usb_string_descriptor	*s = buf;
1146		struct usb_gadget_strings	**sp;
1147
1148		memset(s, 0, 256);
1149		s->bDescriptorType = USB_DT_STRING;
1150
1151		sp = composite->strings;
1152		if (sp)
1153			collect_langs(sp, s->wData);
1154
1155		list_for_each_entry(c, &cdev->configs, list) {
1156			sp = c->strings;
1157			if (sp)
1158				collect_langs(sp, s->wData);
1159
1160			list_for_each_entry(f, &c->functions, list) {
1161				sp = f->strings;
1162				if (sp)
1163					collect_langs(sp, s->wData);
1164			}
1165		}
1166		list_for_each_entry(uc, &cdev->gstrings, list) {
1167			struct usb_gadget_strings **sp;
1168
1169			sp = get_containers_gs(uc);
1170			collect_langs(sp, s->wData);
1171		}
1172
1173		for (len = 0; len <= USB_MAX_STRING_LEN && s->wData[len]; len++)
1174			continue;
1175		if (!len)
1176			return -EINVAL;
1177
1178		s->bLength = 2 * (len + 1);
1179		return s->bLength;
1180	}
1181
1182	if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1183		struct usb_os_string *b = buf;
1184		b->bLength = sizeof(*b);
1185		b->bDescriptorType = USB_DT_STRING;
1186		compiletime_assert(
1187			sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1188			"qwSignature size must be equal to qw_sign");
1189		memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1190		b->bMS_VendorCode = cdev->b_vendor_code;
1191		b->bPad = 0;
1192		return sizeof(*b);
1193	}
1194
1195	list_for_each_entry(uc, &cdev->gstrings, list) {
1196		struct usb_gadget_strings **sp;
1197
1198		sp = get_containers_gs(uc);
1199		len = lookup_string(sp, buf, language, id);
1200		if (len > 0)
1201			return len;
1202	}
1203
1204	/* String IDs are device-scoped, so we look up each string
1205	 * table we're told about.  These lookups are infrequent;
1206	 * simpler-is-better here.
1207	 */
1208	if (composite->strings) {
1209		len = lookup_string(composite->strings, buf, language, id);
1210		if (len > 0)
1211			return len;
1212	}
1213	list_for_each_entry(c, &cdev->configs, list) {
1214		if (c->strings) {
1215			len = lookup_string(c->strings, buf, language, id);
1216			if (len > 0)
1217				return len;
1218		}
1219		list_for_each_entry(f, &c->functions, list) {
1220			if (!f->strings)
1221				continue;
1222			len = lookup_string(f->strings, buf, language, id);
1223			if (len > 0)
1224				return len;
1225		}
1226	}
1227	return -EINVAL;
1228}
1229
1230/**
1231 * usb_string_id() - allocate an unused string ID
1232 * @cdev: the device whose string descriptor IDs are being allocated
1233 * Context: single threaded during gadget setup
1234 *
1235 * @usb_string_id() is called from bind() callbacks to allocate
1236 * string IDs.  Drivers for functions, configurations, or gadgets will
1237 * then store that ID in the appropriate descriptors and string table.
1238 *
1239 * All string identifier should be allocated using this,
1240 * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1241 * that for example different functions don't wrongly assign different
1242 * meanings to the same identifier.
1243 */
1244int usb_string_id(struct usb_composite_dev *cdev)
1245{
1246	if (cdev->next_string_id < 254) {
1247		/* string id 0 is reserved by USB spec for list of
1248		 * supported languages */
1249		/* 255 reserved as well? -- mina86 */
1250		cdev->next_string_id++;
1251		return cdev->next_string_id;
1252	}
1253	return -ENODEV;
1254}
1255EXPORT_SYMBOL_GPL(usb_string_id);
1256
1257/**
1258 * usb_string_ids_tab() - allocate unused string IDs in batch
1259 * @cdev: the device whose string descriptor IDs are being allocated
1260 * @str: an array of usb_string objects to assign numbers to
1261 * Context: single threaded during gadget setup
1262 *
1263 * @usb_string_ids() is called from bind() callbacks to allocate
1264 * string IDs.  Drivers for functions, configurations, or gadgets will
1265 * then copy IDs from the string table to the appropriate descriptors
1266 * and string table for other languages.
1267 *
1268 * All string identifier should be allocated using this,
1269 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1270 * example different functions don't wrongly assign different meanings
1271 * to the same identifier.
1272 */
1273int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1274{
1275	int next = cdev->next_string_id;
1276
1277	for (; str->s; ++str) {
1278		if (unlikely(next >= 254))
1279			return -ENODEV;
1280		str->id = ++next;
1281	}
1282
1283	cdev->next_string_id = next;
1284
1285	return 0;
1286}
1287EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1288
1289static struct usb_gadget_string_container *copy_gadget_strings(
1290		struct usb_gadget_strings **sp, unsigned n_gstrings,
1291		unsigned n_strings)
1292{
1293	struct usb_gadget_string_container *uc;
1294	struct usb_gadget_strings **gs_array;
1295	struct usb_gadget_strings *gs;
1296	struct usb_string *s;
1297	unsigned mem;
1298	unsigned n_gs;
1299	unsigned n_s;
1300	void *stash;
1301
1302	mem = sizeof(*uc);
1303	mem += sizeof(void *) * (n_gstrings + 1);
1304	mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1305	mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1306	uc = kmalloc(mem, GFP_KERNEL);
1307	if (!uc)
1308		return ERR_PTR(-ENOMEM);
1309	gs_array = get_containers_gs(uc);
1310	stash = uc->stash;
1311	stash += sizeof(void *) * (n_gstrings + 1);
1312	for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1313		struct usb_string *org_s;
1314
1315		gs_array[n_gs] = stash;
1316		gs = gs_array[n_gs];
1317		stash += sizeof(struct usb_gadget_strings);
1318		gs->language = sp[n_gs]->language;
1319		gs->strings = stash;
1320		org_s = sp[n_gs]->strings;
1321
1322		for (n_s = 0; n_s < n_strings; n_s++) {
1323			s = stash;
1324			stash += sizeof(struct usb_string);
1325			if (org_s->s)
1326				s->s = org_s->s;
1327			else
1328				s->s = "";
1329			org_s++;
1330		}
1331		s = stash;
1332		s->s = NULL;
1333		stash += sizeof(struct usb_string);
1334
1335	}
1336	gs_array[n_gs] = NULL;
1337	return uc;
1338}
1339
1340/**
1341 * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1342 * @cdev: the device whose string descriptor IDs are being allocated
1343 * and attached.
1344 * @sp: an array of usb_gadget_strings to attach.
1345 * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1346 *
1347 * This function will create a deep copy of usb_gadget_strings and usb_string
1348 * and attach it to the cdev. The actual string (usb_string.s) will not be
1349 * copied but only a referenced will be made. The struct usb_gadget_strings
1350 * array may contain multiple languages and should be NULL terminated.
1351 * The ->language pointer of each struct usb_gadget_strings has to contain the
1352 * same amount of entries.
1353 * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1354 * usb_string entry of es-ES contains the translation of the first usb_string
1355 * entry of en-US. Therefore both entries become the same id assign.
1356 */
1357struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1358		struct usb_gadget_strings **sp, unsigned n_strings)
1359{
1360	struct usb_gadget_string_container *uc;
1361	struct usb_gadget_strings **n_gs;
1362	unsigned n_gstrings = 0;
1363	unsigned i;
1364	int ret;
1365
1366	for (i = 0; sp[i]; i++)
1367		n_gstrings++;
1368
1369	if (!n_gstrings)
1370		return ERR_PTR(-EINVAL);
1371
1372	uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1373	if (IS_ERR(uc))
1374		return ERR_CAST(uc);
1375
1376	n_gs = get_containers_gs(uc);
1377	ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1378	if (ret)
1379		goto err;
1380
1381	for (i = 1; i < n_gstrings; i++) {
1382		struct usb_string *m_s;
1383		struct usb_string *s;
1384		unsigned n;
1385
1386		m_s = n_gs[0]->strings;
1387		s = n_gs[i]->strings;
1388		for (n = 0; n < n_strings; n++) {
1389			s->id = m_s->id;
1390			s++;
1391			m_s++;
1392		}
1393	}
1394	list_add_tail(&uc->list, &cdev->gstrings);
1395	return n_gs[0]->strings;
1396err:
1397	kfree(uc);
1398	return ERR_PTR(ret);
1399}
1400EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1401
1402/**
1403 * usb_string_ids_n() - allocate unused string IDs in batch
1404 * @c: the device whose string descriptor IDs are being allocated
1405 * @n: number of string IDs to allocate
1406 * Context: single threaded during gadget setup
1407 *
1408 * Returns the first requested ID.  This ID and next @n-1 IDs are now
1409 * valid IDs.  At least provided that @n is non-zero because if it
1410 * is, returns last requested ID which is now very useful information.
1411 *
1412 * @usb_string_ids_n() is called from bind() callbacks to allocate
1413 * string IDs.  Drivers for functions, configurations, or gadgets will
1414 * then store that ID in the appropriate descriptors and string table.
1415 *
1416 * All string identifier should be allocated using this,
1417 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1418 * example different functions don't wrongly assign different meanings
1419 * to the same identifier.
1420 */
1421int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1422{
1423	unsigned next = c->next_string_id;
1424	if (unlikely(n > 254 || (unsigned)next + n > 254))
1425		return -ENODEV;
1426	c->next_string_id += n;
1427	return next + 1;
1428}
1429EXPORT_SYMBOL_GPL(usb_string_ids_n);
1430
1431/*-------------------------------------------------------------------------*/
1432
1433static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1434{
1435	struct usb_composite_dev *cdev;
1436
1437	if (req->status || req->actual != req->length)
1438		DBG((struct usb_composite_dev *) ep->driver_data,
1439				"setup complete --> %d, %d/%d\n",
1440				req->status, req->actual, req->length);
1441
1442	/*
1443	 * REVIST The same ep0 requests are shared with function drivers
1444	 * so they don't have to maintain the same ->complete() stubs.
1445	 *
1446	 * Because of that, we need to check for the validity of ->context
1447	 * here, even though we know we've set it to something useful.
1448	 */
1449	if (!req->context)
1450		return;
1451
1452	cdev = req->context;
1453
1454	if (cdev->req == req)
1455		cdev->setup_pending = false;
1456	else if (cdev->os_desc_req == req)
1457		cdev->os_desc_pending = false;
1458	else
1459		WARN(1, "unknown request %p\n", req);
1460}
1461
1462static int composite_ep0_queue(struct usb_composite_dev *cdev,
1463		struct usb_request *req, gfp_t gfp_flags)
1464{
1465	int ret;
1466
1467	ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1468	if (ret == 0) {
1469		if (cdev->req == req)
1470			cdev->setup_pending = true;
1471		else if (cdev->os_desc_req == req)
1472			cdev->os_desc_pending = true;
1473		else
1474			WARN(1, "unknown request %p\n", req);
1475	}
1476
1477	return ret;
1478}
1479
1480static int count_ext_compat(struct usb_configuration *c)
1481{
1482	int i, res;
1483
1484	res = 0;
1485	for (i = 0; i < c->next_interface_id; ++i) {
1486		struct usb_function *f;
1487		int j;
1488
1489		f = c->interface[i];
1490		for (j = 0; j < f->os_desc_n; ++j) {
1491			struct usb_os_desc *d;
1492
1493			if (i != f->os_desc_table[j].if_id)
1494				continue;
1495			d = f->os_desc_table[j].os_desc;
1496			if (d && d->ext_compat_id)
1497				++res;
1498		}
1499	}
1500	BUG_ON(res > 255);
1501	return res;
1502}
1503
1504static int fill_ext_compat(struct usb_configuration *c, u8 *buf)
1505{
1506	int i, count;
1507
1508	count = 16;
1509	buf += 16;
1510	for (i = 0; i < c->next_interface_id; ++i) {
1511		struct usb_function *f;
1512		int j;
1513
1514		f = c->interface[i];
1515		for (j = 0; j < f->os_desc_n; ++j) {
1516			struct usb_os_desc *d;
1517
1518			if (i != f->os_desc_table[j].if_id)
1519				continue;
1520			d = f->os_desc_table[j].os_desc;
1521			if (d && d->ext_compat_id) {
1522				*buf++ = i;
1523				*buf++ = 0x01;
1524				memcpy(buf, d->ext_compat_id, 16);
1525				buf += 22;
1526			} else {
1527				++buf;
1528				*buf = 0x01;
1529				buf += 23;
1530			}
1531			count += 24;
1532			if (count + 24 >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1533				return count;
1534		}
1535	}
1536
1537	return count;
1538}
1539
1540static int count_ext_prop(struct usb_configuration *c, int interface)
1541{
1542	struct usb_function *f;
1543	int j;
1544
1545	f = c->interface[interface];
1546	for (j = 0; j < f->os_desc_n; ++j) {
1547		struct usb_os_desc *d;
1548
1549		if (interface != f->os_desc_table[j].if_id)
1550			continue;
1551		d = f->os_desc_table[j].os_desc;
1552		if (d && d->ext_compat_id)
1553			return d->ext_prop_count;
1554	}
1555	return 0;
1556}
1557
1558static int len_ext_prop(struct usb_configuration *c, int interface)
1559{
1560	struct usb_function *f;
1561	struct usb_os_desc *d;
1562	int j, res;
1563
1564	res = 10; /* header length */
1565	f = c->interface[interface];
1566	for (j = 0; j < f->os_desc_n; ++j) {
1567		if (interface != f->os_desc_table[j].if_id)
1568			continue;
1569		d = f->os_desc_table[j].os_desc;
1570		if (d)
1571			return min(res + d->ext_prop_len, 4096);
1572	}
1573	return res;
1574}
1575
1576static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1577{
1578	struct usb_function *f;
1579	struct usb_os_desc *d;
1580	struct usb_os_desc_ext_prop *ext_prop;
1581	int j, count, n, ret;
1582
1583	f = c->interface[interface];
1584	count = 10; /* header length */
1585	buf += 10;
1586	for (j = 0; j < f->os_desc_n; ++j) {
1587		if (interface != f->os_desc_table[j].if_id)
1588			continue;
1589		d = f->os_desc_table[j].os_desc;
1590		if (d)
1591			list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1592				n = ext_prop->data_len +
1593					ext_prop->name_len + 14;
1594				if (count + n >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1595					return count;
1596				usb_ext_prop_put_size(buf, n);
1597				usb_ext_prop_put_type(buf, ext_prop->type);
1598				ret = usb_ext_prop_put_name(buf, ext_prop->name,
1599							    ext_prop->name_len);
1600				if (ret < 0)
1601					return ret;
1602				switch (ext_prop->type) {
1603				case USB_EXT_PROP_UNICODE:
1604				case USB_EXT_PROP_UNICODE_ENV:
1605				case USB_EXT_PROP_UNICODE_LINK:
1606					usb_ext_prop_put_unicode(buf, ret,
1607							 ext_prop->data,
1608							 ext_prop->data_len);
1609					break;
1610				case USB_EXT_PROP_BINARY:
1611					usb_ext_prop_put_binary(buf, ret,
1612							ext_prop->data,
1613							ext_prop->data_len);
1614					break;
1615				case USB_EXT_PROP_LE32:
1616					/* not implemented */
1617				case USB_EXT_PROP_BE32:
1618					/* not implemented */
1619				default:
1620					return -EINVAL;
1621				}
1622				buf += n;
1623				count += n;
1624			}
1625	}
1626
1627	return count;
1628}
1629
1630/*
1631 * The setup() callback implements all the ep0 functionality that's
1632 * not handled lower down, in hardware or the hardware driver(like
1633 * device and endpoint feature flags, and their status).  It's all
1634 * housekeeping for the gadget function we're implementing.  Most of
1635 * the work is in config and function specific setup.
1636 */
1637int
1638composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1639{
1640	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
1641	struct usb_request		*req = cdev->req;
1642	int				value = -EOPNOTSUPP;
1643	int				status = 0;
1644	u16				w_index = le16_to_cpu(ctrl->wIndex);
1645	u8				intf = w_index & 0xFF;
1646	u16				w_value = le16_to_cpu(ctrl->wValue);
1647	u16				w_length = le16_to_cpu(ctrl->wLength);
1648	struct usb_function		*f = NULL;
1649	u8				endp;
1650
1651	if (w_length > USB_COMP_EP0_BUFSIZ) {
1652		if (ctrl->bRequestType & USB_DIR_IN) {
1653			/* Cast away the const, we are going to overwrite on purpose. */
1654			__le16 *temp = (__le16 *)&ctrl->wLength;
1655
1656			*temp = cpu_to_le16(USB_COMP_EP0_BUFSIZ);
1657			w_length = USB_COMP_EP0_BUFSIZ;
1658		} else {
1659			goto done;
1660		}
1661	}
1662
1663	/* partial re-init of the response message; the function or the
1664	 * gadget might need to intercept e.g. a control-OUT completion
1665	 * when we delegate to it.
1666	 */
1667	req->zero = 0;
1668	req->context = cdev;
1669	req->complete = composite_setup_complete;
1670	req->length = 0;
1671	gadget->ep0->driver_data = cdev;
1672
1673	/*
1674	 * Don't let non-standard requests match any of the cases below
1675	 * by accident.
1676	 */
1677	if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1678		goto unknown;
1679
1680	switch (ctrl->bRequest) {
1681
1682	/* we handle all standard USB descriptors */
1683	case USB_REQ_GET_DESCRIPTOR:
1684		if (ctrl->bRequestType != USB_DIR_IN)
1685			goto unknown;
1686		switch (w_value >> 8) {
1687
1688		case USB_DT_DEVICE:
1689			cdev->desc.bNumConfigurations =
1690				count_configs(cdev, USB_DT_DEVICE);
1691			cdev->desc.bMaxPacketSize0 =
1692				cdev->gadget->ep0->maxpacket;
1693			if (gadget_is_superspeed(gadget)) {
1694				if (gadget->speed >= USB_SPEED_SUPER) {
1695					cdev->desc.bcdUSB = cpu_to_le16(0x0320);
1696					cdev->desc.bMaxPacketSize0 = 9;
1697				} else {
1698					cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1699				}
1700			} else {
1701				if (gadget->lpm_capable)
1702					cdev->desc.bcdUSB = cpu_to_le16(0x0201);
1703				else
1704					cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1705			}
1706
1707			value = min(w_length, (u16) sizeof cdev->desc);
1708			memcpy(req->buf, &cdev->desc, value);
1709			break;
1710		case USB_DT_DEVICE_QUALIFIER:
1711			if (!gadget_is_dualspeed(gadget) ||
1712			    gadget->speed >= USB_SPEED_SUPER)
1713				break;
1714			device_qual(cdev);
1715			value = min_t(int, w_length,
1716				sizeof(struct usb_qualifier_descriptor));
1717			break;
1718		case USB_DT_OTHER_SPEED_CONFIG:
1719			if (!gadget_is_dualspeed(gadget) ||
1720			    gadget->speed >= USB_SPEED_SUPER)
1721				break;
1722			fallthrough;
1723		case USB_DT_CONFIG:
1724			value = config_desc(cdev, w_value);
1725			if (value >= 0)
1726				value = min(w_length, (u16) value);
1727			break;
1728		case USB_DT_STRING:
1729			value = get_string(cdev, req->buf,
1730					w_index, w_value & 0xff);
1731			if (value >= 0)
1732				value = min(w_length, (u16) value);
1733			break;
1734		case USB_DT_BOS:
1735			if (gadget_is_superspeed(gadget) ||
1736			    gadget->lpm_capable) {
1737				value = bos_desc(cdev);
1738				value = min(w_length, (u16) value);
1739			}
1740			break;
1741		case USB_DT_OTG:
1742			if (gadget_is_otg(gadget)) {
1743				struct usb_configuration *config;
1744				int otg_desc_len = 0;
1745
1746				if (cdev->config)
1747					config = cdev->config;
1748				else
1749					config = list_first_entry(
1750							&cdev->configs,
1751						struct usb_configuration, list);
1752				if (!config)
1753					goto done;
1754
1755				if (gadget->otg_caps &&
1756					(gadget->otg_caps->otg_rev >= 0x0200))
1757					otg_desc_len += sizeof(
1758						struct usb_otg20_descriptor);
1759				else
1760					otg_desc_len += sizeof(
1761						struct usb_otg_descriptor);
1762
1763				value = min_t(int, w_length, otg_desc_len);
1764				memcpy(req->buf, config->descriptors[0], value);
1765			}
1766			break;
1767		}
1768		break;
1769
1770	/* any number of configs can work */
1771	case USB_REQ_SET_CONFIGURATION:
1772		if (ctrl->bRequestType != 0)
1773			goto unknown;
1774		if (gadget_is_otg(gadget)) {
1775			if (gadget->a_hnp_support)
1776				DBG(cdev, "HNP available\n");
1777			else if (gadget->a_alt_hnp_support)
1778				DBG(cdev, "HNP on another port\n");
1779			else
1780				VDBG(cdev, "HNP inactive\n");
1781		}
1782		spin_lock(&cdev->lock);
1783		value = set_config(cdev, ctrl, w_value);
1784		spin_unlock(&cdev->lock);
1785		break;
1786	case USB_REQ_GET_CONFIGURATION:
1787		if (ctrl->bRequestType != USB_DIR_IN)
1788			goto unknown;
1789		if (cdev->config)
1790			*(u8 *)req->buf = cdev->config->bConfigurationValue;
1791		else
1792			*(u8 *)req->buf = 0;
1793		value = min(w_length, (u16) 1);
1794		break;
1795
1796	/* function drivers must handle get/set altsetting */
1797	case USB_REQ_SET_INTERFACE:
1798		if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1799			goto unknown;
1800		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1801			break;
1802		f = cdev->config->interface[intf];
1803		if (!f)
1804			break;
1805
1806		/*
1807		 * If there's no get_alt() method, we know only altsetting zero
1808		 * works. There is no need to check if set_alt() is not NULL
1809		 * as we check this in usb_add_function().
1810		 */
1811		if (w_value && !f->get_alt)
1812			break;
1813
1814		spin_lock(&cdev->lock);
1815		value = f->set_alt(f, w_index, w_value);
1816		if (value == USB_GADGET_DELAYED_STATUS) {
1817			DBG(cdev,
1818			 "%s: interface %d (%s) requested delayed status\n",
1819					__func__, intf, f->name);
1820			cdev->delayed_status++;
1821			DBG(cdev, "delayed_status count %d\n",
1822					cdev->delayed_status);
1823		}
1824		spin_unlock(&cdev->lock);
1825		break;
1826	case USB_REQ_GET_INTERFACE:
1827		if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1828			goto unknown;
1829		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1830			break;
1831		f = cdev->config->interface[intf];
1832		if (!f)
1833			break;
1834		/* lots of interfaces only need altsetting zero... */
1835		value = f->get_alt ? f->get_alt(f, w_index) : 0;
1836		if (value < 0)
1837			break;
1838		*((u8 *)req->buf) = value;
1839		value = min(w_length, (u16) 1);
1840		break;
1841	case USB_REQ_GET_STATUS:
1842		if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1843						(w_index == OTG_STS_SELECTOR)) {
1844			if (ctrl->bRequestType != (USB_DIR_IN |
1845							USB_RECIP_DEVICE))
1846				goto unknown;
1847			*((u8 *)req->buf) = gadget->host_request_flag;
1848			value = 1;
1849			break;
1850		}
1851
1852		/*
1853		 * USB 3.0 additions:
1854		 * Function driver should handle get_status request. If such cb
1855		 * wasn't supplied we respond with default value = 0
1856		 * Note: function driver should supply such cb only for the
1857		 * first interface of the function
1858		 */
1859		if (!gadget_is_superspeed(gadget))
1860			goto unknown;
1861		if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1862			goto unknown;
1863		value = 2;	/* This is the length of the get_status reply */
1864		put_unaligned_le16(0, req->buf);
1865		if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1866			break;
1867		f = cdev->config->interface[intf];
1868		if (!f)
1869			break;
1870		status = f->get_status ? f->get_status(f) : 0;
1871		if (status < 0)
1872			break;
1873		put_unaligned_le16(status & 0x0000ffff, req->buf);
1874		break;
1875	/*
1876	 * Function drivers should handle SetFeature/ClearFeature
1877	 * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1878	 * only for the first interface of the function
1879	 */
1880	case USB_REQ_CLEAR_FEATURE:
1881	case USB_REQ_SET_FEATURE:
1882		if (!gadget_is_superspeed(gadget))
1883			goto unknown;
1884		if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1885			goto unknown;
1886		switch (w_value) {
1887		case USB_INTRF_FUNC_SUSPEND:
1888			if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1889				break;
1890			f = cdev->config->interface[intf];
1891			if (!f)
1892				break;
1893			value = 0;
1894			if (f->func_suspend)
1895				value = f->func_suspend(f, w_index >> 8);
1896			if (value < 0) {
1897				ERROR(cdev,
1898				      "func_suspend() returned error %d\n",
1899				      value);
1900				value = 0;
1901			}
1902			break;
1903		}
1904		break;
1905	default:
1906unknown:
1907		/*
1908		 * OS descriptors handling
1909		 */
1910		if (cdev->use_os_string && cdev->os_desc_config &&
1911		    (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1912		    ctrl->bRequest == cdev->b_vendor_code) {
1913			struct usb_configuration	*os_desc_cfg;
1914			u8				*buf;
1915			int				interface;
1916			int				count = 0;
1917
1918			req = cdev->os_desc_req;
1919			req->context = cdev;
1920			req->complete = composite_setup_complete;
1921			buf = req->buf;
1922			os_desc_cfg = cdev->os_desc_config;
1923			w_length = min_t(u16, w_length, USB_COMP_EP0_OS_DESC_BUFSIZ);
1924			memset(buf, 0, w_length);
1925			buf[5] = 0x01;
1926			switch (ctrl->bRequestType & USB_RECIP_MASK) {
1927			case USB_RECIP_DEVICE:
1928				if (w_index != 0x4 || (w_value >> 8))
1929					break;
1930				buf[6] = w_index;
1931				/* Number of ext compat interfaces */
1932				count = count_ext_compat(os_desc_cfg);
1933				buf[8] = count;
1934				count *= 24; /* 24 B/ext compat desc */
1935				count += 16; /* header */
1936				put_unaligned_le32(count, buf);
1937				value = w_length;
1938				if (w_length > 0x10) {
1939					value = fill_ext_compat(os_desc_cfg, buf);
1940					value = min_t(u16, w_length, value);
1941				}
1942				break;
1943			case USB_RECIP_INTERFACE:
1944				if (w_index != 0x5 || (w_value >> 8))
1945					break;
1946				interface = w_value & 0xFF;
1947				if (interface >= MAX_CONFIG_INTERFACES ||
1948				    !os_desc_cfg->interface[interface])
1949					break;
1950				buf[6] = w_index;
1951				count = count_ext_prop(os_desc_cfg,
1952					interface);
1953				put_unaligned_le16(count, buf + 8);
1954				count = len_ext_prop(os_desc_cfg,
1955					interface);
1956				put_unaligned_le32(count, buf);
1957				value = w_length;
1958				if (w_length > 0x0A) {
1959					value = fill_ext_prop(os_desc_cfg,
1960							      interface, buf);
1961					if (value >= 0)
1962						value = min_t(u16, w_length, value);
1963				}
1964				break;
1965			}
1966
1967			goto check_value;
1968		}
1969
1970		VDBG(cdev,
1971			"non-core control req%02x.%02x v%04x i%04x l%d\n",
1972			ctrl->bRequestType, ctrl->bRequest,
1973			w_value, w_index, w_length);
1974
1975		/* functions always handle their interfaces and endpoints...
1976		 * punt other recipients (other, WUSB, ...) to the current
1977		 * configuration code.
1978		 */
1979		if (cdev->config) {
1980			list_for_each_entry(f, &cdev->config->functions, list)
1981				if (f->req_match &&
1982				    f->req_match(f, ctrl, false))
1983					goto try_fun_setup;
1984		} else {
1985			struct usb_configuration *c;
1986			list_for_each_entry(c, &cdev->configs, list)
1987				list_for_each_entry(f, &c->functions, list)
1988					if (f->req_match &&
1989					    f->req_match(f, ctrl, true))
1990						goto try_fun_setup;
1991		}
1992		f = NULL;
1993
1994		switch (ctrl->bRequestType & USB_RECIP_MASK) {
1995		case USB_RECIP_INTERFACE:
1996			if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1997				break;
1998			f = cdev->config->interface[intf];
1999			break;
2000
2001		case USB_RECIP_ENDPOINT:
2002			if (!cdev->config)
2003				break;
2004			endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
2005			list_for_each_entry(f, &cdev->config->functions, list) {
2006				if (test_bit(endp, f->endpoints))
2007					break;
2008			}
2009			if (&f->list == &cdev->config->functions)
2010				f = NULL;
2011			break;
2012		}
2013try_fun_setup:
2014		if (f && f->setup)
2015			value = f->setup(f, ctrl);
2016		else {
2017			struct usb_configuration	*c;
2018
2019			c = cdev->config;
2020			if (!c)
2021				goto done;
2022
2023			/* try current config's setup */
2024			if (c->setup) {
2025				value = c->setup(c, ctrl);
2026				goto done;
2027			}
2028
2029			/* try the only function in the current config */
2030			if (!list_is_singular(&c->functions))
2031				goto done;
2032			f = list_first_entry(&c->functions, struct usb_function,
2033					     list);
2034			if (f->setup)
2035				value = f->setup(f, ctrl);
2036		}
2037
2038		goto done;
2039	}
2040
2041check_value:
2042	/* respond with data transfer before status phase? */
2043	if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
2044		req->length = value;
2045		req->context = cdev;
2046		req->zero = value < w_length;
2047		value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2048		if (value < 0) {
2049			DBG(cdev, "ep_queue --> %d\n", value);
2050			req->status = 0;
2051			composite_setup_complete(gadget->ep0, req);
2052		}
2053	} else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
2054		WARN(cdev,
2055			"%s: Delayed status not supported for w_length != 0",
2056			__func__);
2057	}
2058
2059done:
2060	/* device either stalls (value < 0) or reports success */
2061	return value;
2062}
2063
2064void composite_disconnect(struct usb_gadget *gadget)
2065{
2066	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2067	unsigned long			flags;
2068
2069	/* REVISIT:  should we have config and device level
2070	 * disconnect callbacks?
2071	 */
2072	spin_lock_irqsave(&cdev->lock, flags);
2073	cdev->suspended = 0;
2074	if (cdev->config)
2075		reset_config(cdev);
2076	if (cdev->driver->disconnect)
2077		cdev->driver->disconnect(cdev);
2078	spin_unlock_irqrestore(&cdev->lock, flags);
2079}
2080
2081/*-------------------------------------------------------------------------*/
2082
2083static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2084			      char *buf)
2085{
2086	struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2087	struct usb_composite_dev *cdev = get_gadget_data(gadget);
2088
2089	return sprintf(buf, "%d\n", cdev->suspended);
2090}
2091static DEVICE_ATTR_RO(suspended);
2092
2093static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2094{
2095	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2096	struct usb_gadget_strings	*gstr = cdev->driver->strings[0];
2097	struct usb_string		*dev_str = gstr->strings;
2098
2099	/* composite_disconnect() must already have been called
2100	 * by the underlying peripheral controller driver!
2101	 * so there's no i/o concurrency that could affect the
2102	 * state protected by cdev->lock.
2103	 */
2104	WARN_ON(cdev->config);
2105
2106	while (!list_empty(&cdev->configs)) {
2107		struct usb_configuration	*c;
2108		c = list_first_entry(&cdev->configs,
2109				struct usb_configuration, list);
2110		remove_config(cdev, c);
2111	}
2112	if (cdev->driver->unbind && unbind_driver)
2113		cdev->driver->unbind(cdev);
2114
2115	composite_dev_cleanup(cdev);
2116
2117	if (dev_str[USB_GADGET_MANUFACTURER_IDX].s == cdev->def_manufacturer)
2118		dev_str[USB_GADGET_MANUFACTURER_IDX].s = "";
2119
2120	kfree(cdev->def_manufacturer);
2121	kfree(cdev);
2122	set_gadget_data(gadget, NULL);
2123}
2124
2125static void composite_unbind(struct usb_gadget *gadget)
2126{
2127	__composite_unbind(gadget, true);
2128}
2129
2130static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2131		const struct usb_device_descriptor *old)
2132{
2133	__le16 idVendor;
2134	__le16 idProduct;
2135	__le16 bcdDevice;
2136	u8 iSerialNumber;
2137	u8 iManufacturer;
2138	u8 iProduct;
2139
2140	/*
2141	 * these variables may have been set in
2142	 * usb_composite_overwrite_options()
2143	 */
2144	idVendor = new->idVendor;
2145	idProduct = new->idProduct;
2146	bcdDevice = new->bcdDevice;
2147	iSerialNumber = new->iSerialNumber;
2148	iManufacturer = new->iManufacturer;
2149	iProduct = new->iProduct;
2150
2151	*new = *old;
2152	if (idVendor)
2153		new->idVendor = idVendor;
2154	if (idProduct)
2155		new->idProduct = idProduct;
2156	if (bcdDevice)
2157		new->bcdDevice = bcdDevice;
2158	else
2159		new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2160	if (iSerialNumber)
2161		new->iSerialNumber = iSerialNumber;
2162	if (iManufacturer)
2163		new->iManufacturer = iManufacturer;
2164	if (iProduct)
2165		new->iProduct = iProduct;
2166}
2167
2168int composite_dev_prepare(struct usb_composite_driver *composite,
2169		struct usb_composite_dev *cdev)
2170{
2171	struct usb_gadget *gadget = cdev->gadget;
2172	int ret = -ENOMEM;
2173
2174	/* preallocate control response and buffer */
2175	cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2176	if (!cdev->req)
2177		return -ENOMEM;
2178
2179	cdev->req->buf = kzalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2180	if (!cdev->req->buf)
2181		goto fail;
2182
2183	ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2184	if (ret)
2185		goto fail_dev;
2186
2187	cdev->req->complete = composite_setup_complete;
2188	cdev->req->context = cdev;
2189	gadget->ep0->driver_data = cdev;
2190
2191	cdev->driver = composite;
2192
2193	/*
2194	 * As per USB compliance update, a device that is actively drawing
2195	 * more than 100mA from USB must report itself as bus-powered in
2196	 * the GetStatus(DEVICE) call.
2197	 */
2198	if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2199		usb_gadget_set_selfpowered(gadget);
2200
2201	/* interface and string IDs start at zero via kzalloc.
2202	 * we force endpoints to start unassigned; few controller
2203	 * drivers will zero ep->driver_data.
2204	 */
2205	usb_ep_autoconfig_reset(gadget);
2206	return 0;
2207fail_dev:
2208	kfree(cdev->req->buf);
2209fail:
2210	usb_ep_free_request(gadget->ep0, cdev->req);
2211	cdev->req = NULL;
2212	return ret;
2213}
2214
2215int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2216				  struct usb_ep *ep0)
2217{
2218	int ret = 0;
2219
2220	cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2221	if (!cdev->os_desc_req) {
2222		ret = -ENOMEM;
2223		goto end;
2224	}
2225
2226	cdev->os_desc_req->buf = kmalloc(USB_COMP_EP0_OS_DESC_BUFSIZ,
2227					 GFP_KERNEL);
2228	if (!cdev->os_desc_req->buf) {
2229		ret = -ENOMEM;
2230		usb_ep_free_request(ep0, cdev->os_desc_req);
2231		goto end;
2232	}
2233	cdev->os_desc_req->context = cdev;
2234	cdev->os_desc_req->complete = composite_setup_complete;
2235end:
2236	return ret;
2237}
2238
2239void composite_dev_cleanup(struct usb_composite_dev *cdev)
2240{
2241	struct usb_gadget_string_container *uc, *tmp;
2242	struct usb_ep			   *ep, *tmp_ep;
2243
2244	list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2245		list_del(&uc->list);
2246		kfree(uc);
2247	}
2248	if (cdev->os_desc_req) {
2249		if (cdev->os_desc_pending)
2250			usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2251
2252		kfree(cdev->os_desc_req->buf);
2253		cdev->os_desc_req->buf = NULL;
2254		usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2255		cdev->os_desc_req = NULL;
2256	}
2257	if (cdev->req) {
2258		if (cdev->setup_pending)
2259			usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2260
2261		kfree(cdev->req->buf);
2262		cdev->req->buf = NULL;
2263		usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2264		cdev->req = NULL;
2265	}
2266	cdev->next_string_id = 0;
2267	device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2268
2269	/*
2270	 * Some UDC backends have a dynamic EP allocation scheme.
2271	 *
2272	 * In that case, the dispose() callback is used to notify the
2273	 * backend that the EPs are no longer in use.
2274	 *
2275	 * Note: The UDC backend can remove the EP from the ep_list as
2276	 *	 a result, so we need to use the _safe list iterator.
2277	 */
2278	list_for_each_entry_safe(ep, tmp_ep,
2279				 &cdev->gadget->ep_list, ep_list) {
2280		if (ep->ops->dispose)
2281			ep->ops->dispose(ep);
2282	}
2283}
2284
2285static int composite_bind(struct usb_gadget *gadget,
2286		struct usb_gadget_driver *gdriver)
2287{
2288	struct usb_composite_dev	*cdev;
2289	struct usb_composite_driver	*composite = to_cdriver(gdriver);
2290	int				status = -ENOMEM;
2291
2292	cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2293	if (!cdev)
2294		return status;
2295
2296	spin_lock_init(&cdev->lock);
2297	cdev->gadget = gadget;
2298	set_gadget_data(gadget, cdev);
2299	INIT_LIST_HEAD(&cdev->configs);
2300	INIT_LIST_HEAD(&cdev->gstrings);
2301
2302	status = composite_dev_prepare(composite, cdev);
2303	if (status)
2304		goto fail;
2305
2306	/* composite gadget needs to assign strings for whole device (like
2307	 * serial number), register function drivers, potentially update
2308	 * power state and consumption, etc
2309	 */
2310	status = composite->bind(cdev);
2311	if (status < 0)
2312		goto fail;
2313
2314	if (cdev->use_os_string) {
2315		status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2316		if (status)
2317			goto fail;
2318	}
2319
2320	update_unchanged_dev_desc(&cdev->desc, composite->dev);
2321
2322	/* has userspace failed to provide a serial number? */
2323	if (composite->needs_serial && !cdev->desc.iSerialNumber)
2324		WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2325
2326	INFO(cdev, "%s ready\n", composite->name);
2327	return 0;
2328
2329fail:
2330	__composite_unbind(gadget, false);
2331	return status;
2332}
2333
2334/*-------------------------------------------------------------------------*/
2335
2336void composite_suspend(struct usb_gadget *gadget)
2337{
2338	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2339	struct usb_function		*f;
2340
2341	/* REVISIT:  should we have config level
2342	 * suspend/resume callbacks?
2343	 */
2344	DBG(cdev, "suspend\n");
2345	if (cdev->config) {
2346		list_for_each_entry(f, &cdev->config->functions, list) {
2347			if (f->suspend)
2348				f->suspend(f);
2349		}
2350	}
2351	if (cdev->driver->suspend)
2352		cdev->driver->suspend(cdev);
2353
2354	cdev->suspended = 1;
2355
2356	usb_gadget_set_selfpowered(gadget);
2357	usb_gadget_vbus_draw(gadget, 2);
2358}
2359
2360void composite_resume(struct usb_gadget *gadget)
2361{
2362	struct usb_composite_dev	*cdev = get_gadget_data(gadget);
2363	struct usb_function		*f;
2364	unsigned			maxpower;
2365
2366	/* REVISIT:  should we have config level
2367	 * suspend/resume callbacks?
2368	 */
2369	DBG(cdev, "resume\n");
2370	if (cdev->driver->resume)
2371		cdev->driver->resume(cdev);
2372	if (cdev->config) {
2373		list_for_each_entry(f, &cdev->config->functions, list) {
2374			if (f->resume)
2375				f->resume(f);
2376		}
2377
2378		maxpower = cdev->config->MaxPower ?
2379			cdev->config->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
2380		if (gadget->speed < USB_SPEED_SUPER)
2381			maxpower = min(maxpower, 500U);
2382		else
2383			maxpower = min(maxpower, 900U);
2384
2385		if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW)
2386			usb_gadget_clear_selfpowered(gadget);
2387
2388		usb_gadget_vbus_draw(gadget, maxpower);
2389	}
2390
2391	cdev->suspended = 0;
2392}
2393
2394/*-------------------------------------------------------------------------*/
2395
2396static const struct usb_gadget_driver composite_driver_template = {
2397	.bind		= composite_bind,
2398	.unbind		= composite_unbind,
2399
2400	.setup		= composite_setup,
2401	.reset		= composite_disconnect,
2402	.disconnect	= composite_disconnect,
2403
2404	.suspend	= composite_suspend,
2405	.resume		= composite_resume,
2406
2407	.driver	= {
2408		.owner		= THIS_MODULE,
2409	},
2410};
2411
2412/**
2413 * usb_composite_probe() - register a composite driver
2414 * @driver: the driver to register
2415 *
2416 * Context: single threaded during gadget setup
2417 *
2418 * This function is used to register drivers using the composite driver
2419 * framework.  The return value is zero, or a negative errno value.
2420 * Those values normally come from the driver's @bind method, which does
2421 * all the work of setting up the driver to match the hardware.
2422 *
2423 * On successful return, the gadget is ready to respond to requests from
2424 * the host, unless one of its components invokes usb_gadget_disconnect()
2425 * while it was binding.  That would usually be done in order to wait for
2426 * some userspace participation.
2427 */
2428int usb_composite_probe(struct usb_composite_driver *driver)
2429{
2430	struct usb_gadget_driver *gadget_driver;
2431
2432	if (!driver || !driver->dev || !driver->bind)
2433		return -EINVAL;
2434
2435	if (!driver->name)
2436		driver->name = "composite";
2437
2438	driver->gadget_driver = composite_driver_template;
2439	gadget_driver = &driver->gadget_driver;
2440
2441	gadget_driver->function =  (char *) driver->name;
2442	gadget_driver->driver.name = driver->name;
2443	gadget_driver->max_speed = driver->max_speed;
2444
2445	return usb_gadget_probe_driver(gadget_driver);
2446}
2447EXPORT_SYMBOL_GPL(usb_composite_probe);
2448
2449/**
2450 * usb_composite_unregister() - unregister a composite driver
2451 * @driver: the driver to unregister
2452 *
2453 * This function is used to unregister drivers using the composite
2454 * driver framework.
2455 */
2456void usb_composite_unregister(struct usb_composite_driver *driver)
2457{
2458	usb_gadget_unregister_driver(&driver->gadget_driver);
2459}
2460EXPORT_SYMBOL_GPL(usb_composite_unregister);
2461
2462/**
2463 * usb_composite_setup_continue() - Continue with the control transfer
2464 * @cdev: the composite device who's control transfer was kept waiting
2465 *
2466 * This function must be called by the USB function driver to continue
2467 * with the control transfer's data/status stage in case it had requested to
2468 * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2469 * can request the composite framework to delay the setup request's data/status
2470 * stages by returning USB_GADGET_DELAYED_STATUS.
2471 */
2472void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2473{
2474	int			value;
2475	struct usb_request	*req = cdev->req;
2476	unsigned long		flags;
2477
2478	DBG(cdev, "%s\n", __func__);
2479	spin_lock_irqsave(&cdev->lock, flags);
2480
2481	if (cdev->delayed_status == 0) {
2482		WARN(cdev, "%s: Unexpected call\n", __func__);
2483
2484	} else if (--cdev->delayed_status == 0) {
2485		DBG(cdev, "%s: Completing delayed status\n", __func__);
2486		req->length = 0;
2487		req->context = cdev;
2488		value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2489		if (value < 0) {
2490			DBG(cdev, "ep_queue --> %d\n", value);
2491			req->status = 0;
2492			composite_setup_complete(cdev->gadget->ep0, req);
2493		}
2494	}
2495
2496	spin_unlock_irqrestore(&cdev->lock, flags);
2497}
2498EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2499
2500static char *composite_default_mfr(struct usb_gadget *gadget)
2501{
2502	return kasprintf(GFP_KERNEL, "%s %s with %s", init_utsname()->sysname,
2503			 init_utsname()->release, gadget->name);
2504}
2505
2506void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2507		struct usb_composite_overwrite *covr)
2508{
2509	struct usb_device_descriptor	*desc = &cdev->desc;
2510	struct usb_gadget_strings	*gstr = cdev->driver->strings[0];
2511	struct usb_string		*dev_str = gstr->strings;
2512
2513	if (covr->idVendor)
2514		desc->idVendor = cpu_to_le16(covr->idVendor);
2515
2516	if (covr->idProduct)
2517		desc->idProduct = cpu_to_le16(covr->idProduct);
2518
2519	if (covr->bcdDevice)
2520		desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2521
2522	if (covr->serial_number) {
2523		desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2524		dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2525	}
2526	if (covr->manufacturer) {
2527		desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2528		dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2529
2530	} else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2531		desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2532		cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2533		dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2534	}
2535
2536	if (covr->product) {
2537		desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2538		dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2539	}
2540}
2541EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2542
2543MODULE_LICENSE("GPL");
2544MODULE_AUTHOR("David Brownell");
2545