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 #include <linux/bitfield.h>
17
18 #include <linux/usb/composite.h>
19 #include <linux/usb/otg.h>
20 #include <asm/unaligned.h>
21
22 #include "u_os_desc.h"
23
24 /**
25 * struct usb_os_string - represents OS String to be reported by a gadget
26 * @bLength: total length of the entire descritor, always 0x12
27 * @bDescriptorType: USB_DT_STRING
28 * @qwSignature: the OS String proper
29 * @bMS_VendorCode: code used by the host for subsequent requests
30 * @bPad: not used, must be zero
31 */
32 struct usb_os_string {
33 __u8 bLength;
34 __u8 bDescriptorType;
35 __u8 qwSignature[OS_STRING_QW_SIGN_LEN];
36 __u8 bMS_VendorCode;
37 __u8 bPad;
38 } __packed;
39
40 /*
41 * The code in this file is utility code, used to build a gadget driver
42 * from one or more "function" drivers, one or more "configuration"
43 * objects, and a "usb_composite_driver" by gluing them together along
44 * with the relevant device-wide data.
45 */
46
get_containers_gs(struct usb_gadget_string_container * uc)47 static struct usb_gadget_strings **get_containers_gs(
48 struct usb_gadget_string_container *uc)
49 {
50 return (struct usb_gadget_strings **)uc->stash;
51 }
52
53 /**
54 * function_descriptors() - get function descriptors for speed
55 * @f: the function
56 * @speed: the speed
57 *
58 * Returns the descriptors or NULL if not set.
59 */
60 static struct usb_descriptor_header **
function_descriptors(struct usb_function * f,enum usb_device_speed speed)61 function_descriptors(struct usb_function *f,
62 enum usb_device_speed speed)
63 {
64 struct usb_descriptor_header **descriptors;
65
66 /*
67 * NOTE: we try to help gadget drivers which might not be setting
68 * max_speed appropriately.
69 */
70
71 switch (speed) {
72 case USB_SPEED_SUPER_PLUS:
73 descriptors = f->ssp_descriptors;
74 if (descriptors)
75 break;
76 fallthrough;
77 case USB_SPEED_SUPER:
78 descriptors = f->ss_descriptors;
79 if (descriptors)
80 break;
81 fallthrough;
82 case USB_SPEED_HIGH:
83 descriptors = f->hs_descriptors;
84 if (descriptors)
85 break;
86 fallthrough;
87 default:
88 descriptors = f->fs_descriptors;
89 }
90
91 /*
92 * if we can't find any descriptors at all, then this gadget deserves to
93 * Oops with a NULL pointer dereference
94 */
95
96 return descriptors;
97 }
98
99 /**
100 * next_desc() - advance to the next desc_type descriptor
101 * @t: currect pointer within descriptor array
102 * @desc_type: descriptor type
103 *
104 * Return: next desc_type descriptor or NULL
105 *
106 * Iterate over @t until either desc_type descriptor found or
107 * NULL (that indicates end of list) encountered
108 */
109 static struct usb_descriptor_header**
next_desc(struct usb_descriptor_header ** t,u8 desc_type)110 next_desc(struct usb_descriptor_header **t, u8 desc_type)
111 {
112 for (; *t; t++) {
113 if ((*t)->bDescriptorType == desc_type)
114 return t;
115 }
116 return NULL;
117 }
118
119 /*
120 * for_each_desc() - iterate over desc_type descriptors in the
121 * descriptors list
122 * @start: pointer within descriptor array.
123 * @iter_desc: desc_type descriptor to use as the loop cursor
124 * @desc_type: wanted descriptr type
125 */
126 #define for_each_desc(start, iter_desc, desc_type) \
127 for (iter_desc = next_desc(start, desc_type); \
128 iter_desc; iter_desc = next_desc(iter_desc + 1, desc_type))
129
130 /**
131 * config_ep_by_speed_and_alt() - configures the given endpoint
132 * according to gadget speed.
133 * @g: pointer to the gadget
134 * @f: usb function
135 * @_ep: the endpoint to configure
136 * @alt: alternate setting number
137 *
138 * Return: error code, 0 on success
139 *
140 * This function chooses the right descriptors for a given
141 * endpoint according to gadget speed and saves it in the
142 * endpoint desc field. If the endpoint already has a descriptor
143 * assigned to it - overwrites it with currently corresponding
144 * descriptor. The endpoint maxpacket field is updated according
145 * to the chosen descriptor.
146 * Note: the supplied function should hold all the descriptors
147 * for supported speeds
148 */
config_ep_by_speed_and_alt(struct usb_gadget * g,struct usb_function * f,struct usb_ep * _ep,u8 alt)149 int config_ep_by_speed_and_alt(struct usb_gadget *g,
150 struct usb_function *f,
151 struct usb_ep *_ep,
152 u8 alt)
153 {
154 struct usb_endpoint_descriptor *chosen_desc = NULL;
155 struct usb_interface_descriptor *int_desc = NULL;
156 struct usb_descriptor_header **speed_desc = NULL;
157
158 struct usb_ss_ep_comp_descriptor *comp_desc = NULL;
159 int want_comp_desc = 0;
160
161 struct usb_descriptor_header **d_spd; /* cursor for speed desc */
162 struct usb_composite_dev *cdev;
163 bool incomplete_desc = false;
164
165 if (!g || !f || !_ep)
166 return -EIO;
167
168 /* select desired speed */
169 switch (g->speed) {
170 case USB_SPEED_SUPER_PLUS:
171 if (gadget_is_superspeed_plus(g)) {
172 if (f->ssp_descriptors) {
173 speed_desc = f->ssp_descriptors;
174 want_comp_desc = 1;
175 break;
176 }
177 incomplete_desc = true;
178 }
179 fallthrough;
180 case USB_SPEED_SUPER:
181 if (gadget_is_superspeed(g)) {
182 if (f->ss_descriptors) {
183 speed_desc = f->ss_descriptors;
184 want_comp_desc = 1;
185 break;
186 }
187 incomplete_desc = true;
188 }
189 fallthrough;
190 case USB_SPEED_HIGH:
191 if (gadget_is_dualspeed(g)) {
192 if (f->hs_descriptors) {
193 speed_desc = f->hs_descriptors;
194 break;
195 }
196 incomplete_desc = true;
197 }
198 fallthrough;
199 default:
200 speed_desc = f->fs_descriptors;
201 }
202
203 cdev = get_gadget_data(g);
204 if (incomplete_desc)
205 WARNING(cdev,
206 "%s doesn't hold the descriptors for current speed\n",
207 f->name);
208
209 /* find correct alternate setting descriptor */
210 for_each_desc(speed_desc, d_spd, USB_DT_INTERFACE) {
211 int_desc = (struct usb_interface_descriptor *)*d_spd;
212
213 if (int_desc->bAlternateSetting == alt) {
214 speed_desc = d_spd;
215 goto intf_found;
216 }
217 }
218 return -EIO;
219
220 intf_found:
221 /* find descriptors */
222 for_each_desc(speed_desc, d_spd, USB_DT_ENDPOINT) {
223 chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
224 if (chosen_desc->bEndpointAddress == _ep->address)
225 goto ep_found;
226 }
227 return -EIO;
228
229 ep_found:
230 /* commit results */
231 _ep->maxpacket = usb_endpoint_maxp(chosen_desc);
232 _ep->desc = chosen_desc;
233 _ep->comp_desc = NULL;
234 _ep->maxburst = 0;
235 _ep->mult = 1;
236
237 if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
238 usb_endpoint_xfer_int(_ep->desc)))
239 _ep->mult = usb_endpoint_maxp_mult(_ep->desc);
240
241 if (!want_comp_desc)
242 return 0;
243
244 /*
245 * Companion descriptor should follow EP descriptor
246 * USB 3.0 spec, #9.6.7
247 */
248 comp_desc = (struct usb_ss_ep_comp_descriptor *)*(++d_spd);
249 if (!comp_desc ||
250 (comp_desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP))
251 return -EIO;
252 _ep->comp_desc = comp_desc;
253 if (g->speed >= USB_SPEED_SUPER) {
254 switch (usb_endpoint_type(_ep->desc)) {
255 case USB_ENDPOINT_XFER_ISOC:
256 /* mult: bits 1:0 of bmAttributes */
257 _ep->mult = (comp_desc->bmAttributes & 0x3) + 1;
258 fallthrough;
259 case USB_ENDPOINT_XFER_BULK:
260 case USB_ENDPOINT_XFER_INT:
261 _ep->maxburst = comp_desc->bMaxBurst + 1;
262 break;
263 default:
264 if (comp_desc->bMaxBurst != 0)
265 ERROR(cdev, "ep0 bMaxBurst must be 0\n");
266 _ep->maxburst = 1;
267 break;
268 }
269 }
270 return 0;
271 }
272 EXPORT_SYMBOL_GPL(config_ep_by_speed_and_alt);
273
274 /**
275 * config_ep_by_speed() - configures the given endpoint
276 * according to gadget speed.
277 * @g: pointer to the gadget
278 * @f: usb function
279 * @_ep: the endpoint to configure
280 *
281 * Return: error code, 0 on success
282 *
283 * This function chooses the right descriptors for a given
284 * endpoint according to gadget speed and saves it in the
285 * endpoint desc field. If the endpoint already has a descriptor
286 * assigned to it - overwrites it with currently corresponding
287 * descriptor. The endpoint maxpacket field is updated according
288 * to the chosen descriptor.
289 * Note: the supplied function should hold all the descriptors
290 * for supported speeds
291 */
config_ep_by_speed(struct usb_gadget * g,struct usb_function * f,struct usb_ep * _ep)292 int config_ep_by_speed(struct usb_gadget *g,
293 struct usb_function *f,
294 struct usb_ep *_ep)
295 {
296 return config_ep_by_speed_and_alt(g, f, _ep, 0);
297 }
298 EXPORT_SYMBOL_GPL(config_ep_by_speed);
299
300 /**
301 * usb_add_function() - add a function to a configuration
302 * @config: the configuration
303 * @function: the function being added
304 * Context: single threaded during gadget setup
305 *
306 * After initialization, each configuration must have one or more
307 * functions added to it. Adding a function involves calling its @bind()
308 * method to allocate resources such as interface and string identifiers
309 * and endpoints.
310 *
311 * This function returns the value of the function's bind(), which is
312 * zero for success else a negative errno value.
313 */
usb_add_function(struct usb_configuration * config,struct usb_function * function)314 int usb_add_function(struct usb_configuration *config,
315 struct usb_function *function)
316 {
317 int value = -EINVAL;
318
319 DBG(config->cdev, "adding '%s'/%p to config '%s'/%p\n",
320 function->name, function,
321 config->label, config);
322
323 if (!function->set_alt || !function->disable)
324 goto done;
325
326 function->config = config;
327 list_add_tail(&function->list, &config->functions);
328
329 if (function->bind_deactivated) {
330 value = usb_function_deactivate(function);
331 if (value)
332 goto done;
333 }
334
335 /* REVISIT *require* function->bind? */
336 if (function->bind) {
337 value = function->bind(config, function);
338 if (value < 0) {
339 list_del(&function->list);
340 function->config = NULL;
341 }
342 } else
343 value = 0;
344
345 /* We allow configurations that don't work at both speeds.
346 * If we run into a lowspeed Linux system, treat it the same
347 * as full speed ... it's the function drivers that will need
348 * to avoid bulk and ISO transfers.
349 */
350 if (!config->fullspeed && function->fs_descriptors)
351 config->fullspeed = true;
352 if (!config->highspeed && function->hs_descriptors)
353 config->highspeed = true;
354 if (!config->superspeed && function->ss_descriptors)
355 config->superspeed = true;
356 if (!config->superspeed_plus && function->ssp_descriptors)
357 config->superspeed_plus = true;
358
359 done:
360 if (value)
361 DBG(config->cdev, "adding '%s'/%p --> %d\n",
362 function->name, function, value);
363 return value;
364 }
365 EXPORT_SYMBOL_GPL(usb_add_function);
366
usb_remove_function(struct usb_configuration * c,struct usb_function * f)367 void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
368 {
369 if (f->disable)
370 f->disable(f);
371
372 bitmap_zero(f->endpoints, 32);
373 list_del(&f->list);
374 if (f->unbind)
375 f->unbind(c, f);
376
377 if (f->bind_deactivated)
378 usb_function_activate(f);
379 }
380 EXPORT_SYMBOL_GPL(usb_remove_function);
381
382 /**
383 * usb_function_deactivate - prevent function and gadget enumeration
384 * @function: the function that isn't yet ready to respond
385 *
386 * Blocks response of the gadget driver to host enumeration by
387 * preventing the data line pullup from being activated. This is
388 * normally called during @bind() processing to change from the
389 * initial "ready to respond" state, or when a required resource
390 * becomes available.
391 *
392 * For example, drivers that serve as a passthrough to a userspace
393 * daemon can block enumeration unless that daemon (such as an OBEX,
394 * MTP, or print server) is ready to handle host requests.
395 *
396 * Not all systems support software control of their USB peripheral
397 * data pullups.
398 *
399 * Returns zero on success, else negative errno.
400 */
usb_function_deactivate(struct usb_function * function)401 int usb_function_deactivate(struct usb_function *function)
402 {
403 struct usb_composite_dev *cdev = function->config->cdev;
404 unsigned long flags;
405 int status = 0;
406
407 spin_lock_irqsave(&cdev->lock, flags);
408
409 if (cdev->deactivations == 0) {
410 spin_unlock_irqrestore(&cdev->lock, flags);
411 status = usb_gadget_deactivate(cdev->gadget);
412 spin_lock_irqsave(&cdev->lock, flags);
413 }
414 if (status == 0)
415 cdev->deactivations++;
416
417 spin_unlock_irqrestore(&cdev->lock, flags);
418 return status;
419 }
420 EXPORT_SYMBOL_GPL(usb_function_deactivate);
421
422 /**
423 * usb_function_activate - allow function and gadget enumeration
424 * @function: function on which usb_function_activate() was called
425 *
426 * Reverses effect of usb_function_deactivate(). If no more functions
427 * are delaying their activation, the gadget driver will respond to
428 * host enumeration procedures.
429 *
430 * Returns zero on success, else negative errno.
431 */
usb_function_activate(struct usb_function * function)432 int usb_function_activate(struct usb_function *function)
433 {
434 struct usb_composite_dev *cdev = function->config->cdev;
435 unsigned long flags;
436 int status = 0;
437
438 spin_lock_irqsave(&cdev->lock, flags);
439
440 if (WARN_ON(cdev->deactivations == 0))
441 status = -EINVAL;
442 else {
443 cdev->deactivations--;
444 if (cdev->deactivations == 0) {
445 spin_unlock_irqrestore(&cdev->lock, flags);
446 status = usb_gadget_activate(cdev->gadget);
447 spin_lock_irqsave(&cdev->lock, flags);
448 }
449 }
450
451 spin_unlock_irqrestore(&cdev->lock, flags);
452 return status;
453 }
454 EXPORT_SYMBOL_GPL(usb_function_activate);
455
456 /**
457 * usb_interface_id() - allocate an unused interface ID
458 * @config: configuration associated with the interface
459 * @function: function handling the interface
460 * Context: single threaded during gadget setup
461 *
462 * usb_interface_id() is called from usb_function.bind() callbacks to
463 * allocate new interface IDs. The function driver will then store that
464 * ID in interface, association, CDC union, and other descriptors. It
465 * will also handle any control requests targeted at that interface,
466 * particularly changing its altsetting via set_alt(). There may
467 * also be class-specific or vendor-specific requests to handle.
468 *
469 * All interface identifier should be allocated using this routine, to
470 * ensure that for example different functions don't wrongly assign
471 * different meanings to the same identifier. Note that since interface
472 * identifiers are configuration-specific, functions used in more than
473 * one configuration (or more than once in a given configuration) need
474 * multiple versions of the relevant descriptors.
475 *
476 * Returns the interface ID which was allocated; or -ENODEV if no
477 * more interface IDs can be allocated.
478 */
usb_interface_id(struct usb_configuration * config,struct usb_function * function)479 int usb_interface_id(struct usb_configuration *config,
480 struct usb_function *function)
481 {
482 unsigned id = config->next_interface_id;
483
484 if (id < MAX_CONFIG_INTERFACES) {
485 config->interface[id] = function;
486 config->next_interface_id = id + 1;
487 return id;
488 }
489 return -ENODEV;
490 }
491 EXPORT_SYMBOL_GPL(usb_interface_id);
492
encode_bMaxPower(enum usb_device_speed speed,struct usb_configuration * c)493 static u8 encode_bMaxPower(enum usb_device_speed speed,
494 struct usb_configuration *c)
495 {
496 unsigned val;
497
498 if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
499 val = c->MaxPower;
500 else
501 val = CONFIG_USB_GADGET_VBUS_DRAW;
502 if (!val)
503 return 0;
504 if (speed < USB_SPEED_SUPER)
505 return min(val, 500U) / 2;
506 else
507 /*
508 * USB 3.x supports up to 900mA, but since 900 isn't divisible
509 * by 8 the integral division will effectively cap to 896mA.
510 */
511 return min(val, 900U) / 8;
512 }
513
check_remote_wakeup_config(struct usb_gadget * g,struct usb_configuration * c)514 void check_remote_wakeup_config(struct usb_gadget *g,
515 struct usb_configuration *c)
516 {
517 if (USB_CONFIG_ATT_WAKEUP & c->bmAttributes) {
518 /* Reset the rw bit if gadget is not capable of it */
519 if (!g->wakeup_capable && g->ops->set_remote_wakeup) {
520 WARN(c->cdev, "Clearing wakeup bit for config c.%d\n",
521 c->bConfigurationValue);
522 c->bmAttributes &= ~USB_CONFIG_ATT_WAKEUP;
523 }
524 }
525 }
526
config_buf(struct usb_configuration * config,enum usb_device_speed speed,void * buf,u8 type)527 static int config_buf(struct usb_configuration *config,
528 enum usb_device_speed speed, void *buf, u8 type)
529 {
530 struct usb_config_descriptor *c = buf;
531 void *next = buf + USB_DT_CONFIG_SIZE;
532 int len;
533 struct usb_function *f;
534 int status;
535
536 len = USB_COMP_EP0_BUFSIZ - USB_DT_CONFIG_SIZE;
537 /* write the config descriptor */
538 c = buf;
539 c->bLength = USB_DT_CONFIG_SIZE;
540 c->bDescriptorType = type;
541 /* wTotalLength is written later */
542 c->bNumInterfaces = config->next_interface_id;
543 c->bConfigurationValue = config->bConfigurationValue;
544 c->iConfiguration = config->iConfiguration;
545 c->bmAttributes = USB_CONFIG_ATT_ONE | config->bmAttributes;
546 c->bMaxPower = encode_bMaxPower(speed, config);
547
548 /* There may be e.g. OTG descriptors */
549 if (config->descriptors) {
550 status = usb_descriptor_fillbuf(next, len,
551 config->descriptors);
552 if (status < 0)
553 return status;
554 len -= status;
555 next += status;
556 }
557
558 /* add each function's descriptors */
559 list_for_each_entry(f, &config->functions, list) {
560 struct usb_descriptor_header **descriptors;
561
562 descriptors = function_descriptors(f, speed);
563 if (!descriptors)
564 continue;
565 status = usb_descriptor_fillbuf(next, len,
566 (const struct usb_descriptor_header **) descriptors);
567 if (status < 0)
568 return status;
569 len -= status;
570 next += status;
571 }
572
573 len = next - buf;
574 c->wTotalLength = cpu_to_le16(len);
575 return len;
576 }
577
config_desc(struct usb_composite_dev * cdev,unsigned w_value)578 static int config_desc(struct usb_composite_dev *cdev, unsigned w_value)
579 {
580 struct usb_gadget *gadget = cdev->gadget;
581 struct usb_configuration *c;
582 struct list_head *pos;
583 u8 type = w_value >> 8;
584 enum usb_device_speed speed = USB_SPEED_UNKNOWN;
585
586 if (gadget->speed >= USB_SPEED_SUPER)
587 speed = gadget->speed;
588 else if (gadget_is_dualspeed(gadget)) {
589 int hs = 0;
590 if (gadget->speed == USB_SPEED_HIGH)
591 hs = 1;
592 if (type == USB_DT_OTHER_SPEED_CONFIG)
593 hs = !hs;
594 if (hs)
595 speed = USB_SPEED_HIGH;
596
597 }
598
599 /* This is a lookup by config *INDEX* */
600 w_value &= 0xff;
601
602 pos = &cdev->configs;
603 c = cdev->os_desc_config;
604 if (c)
605 goto check_config;
606
607 while ((pos = pos->next) != &cdev->configs) {
608 c = list_entry(pos, typeof(*c), list);
609
610 /* skip OS Descriptors config which is handled separately */
611 if (c == cdev->os_desc_config)
612 continue;
613
614 check_config:
615 /* ignore configs that won't work at this speed */
616 switch (speed) {
617 case USB_SPEED_SUPER_PLUS:
618 if (!c->superspeed_plus)
619 continue;
620 break;
621 case USB_SPEED_SUPER:
622 if (!c->superspeed)
623 continue;
624 break;
625 case USB_SPEED_HIGH:
626 if (!c->highspeed)
627 continue;
628 break;
629 default:
630 if (!c->fullspeed)
631 continue;
632 }
633
634 if (w_value == 0)
635 return config_buf(c, speed, cdev->req->buf, type);
636 w_value--;
637 }
638 return -EINVAL;
639 }
640
count_configs(struct usb_composite_dev * cdev,unsigned type)641 static int count_configs(struct usb_composite_dev *cdev, unsigned type)
642 {
643 struct usb_gadget *gadget = cdev->gadget;
644 struct usb_configuration *c;
645 unsigned count = 0;
646 int hs = 0;
647 int ss = 0;
648 int ssp = 0;
649
650 if (gadget_is_dualspeed(gadget)) {
651 if (gadget->speed == USB_SPEED_HIGH)
652 hs = 1;
653 if (gadget->speed == USB_SPEED_SUPER)
654 ss = 1;
655 if (gadget->speed == USB_SPEED_SUPER_PLUS)
656 ssp = 1;
657 if (type == USB_DT_DEVICE_QUALIFIER)
658 hs = !hs;
659 }
660 list_for_each_entry(c, &cdev->configs, list) {
661 /* ignore configs that won't work at this speed */
662 if (ssp) {
663 if (!c->superspeed_plus)
664 continue;
665 } else if (ss) {
666 if (!c->superspeed)
667 continue;
668 } else if (hs) {
669 if (!c->highspeed)
670 continue;
671 } else {
672 if (!c->fullspeed)
673 continue;
674 }
675 count++;
676 }
677 return count;
678 }
679
680 /**
681 * bos_desc() - prepares the BOS descriptor.
682 * @cdev: pointer to usb_composite device to generate the bos
683 * descriptor for
684 *
685 * This function generates the BOS (Binary Device Object)
686 * descriptor and its device capabilities descriptors. The BOS
687 * descriptor should be supported by a SuperSpeed device.
688 */
bos_desc(struct usb_composite_dev * cdev)689 static int bos_desc(struct usb_composite_dev *cdev)
690 {
691 struct usb_ext_cap_descriptor *usb_ext;
692 struct usb_dcd_config_params dcd_config_params;
693 struct usb_bos_descriptor *bos = cdev->req->buf;
694 unsigned int besl = 0;
695
696 bos->bLength = USB_DT_BOS_SIZE;
697 bos->bDescriptorType = USB_DT_BOS;
698
699 bos->wTotalLength = cpu_to_le16(USB_DT_BOS_SIZE);
700 bos->bNumDeviceCaps = 0;
701
702 /* Get Controller configuration */
703 if (cdev->gadget->ops->get_config_params) {
704 cdev->gadget->ops->get_config_params(cdev->gadget,
705 &dcd_config_params);
706 } else {
707 dcd_config_params.besl_baseline =
708 USB_DEFAULT_BESL_UNSPECIFIED;
709 dcd_config_params.besl_deep =
710 USB_DEFAULT_BESL_UNSPECIFIED;
711 dcd_config_params.bU1devExitLat =
712 USB_DEFAULT_U1_DEV_EXIT_LAT;
713 dcd_config_params.bU2DevExitLat =
714 cpu_to_le16(USB_DEFAULT_U2_DEV_EXIT_LAT);
715 }
716
717 if (dcd_config_params.besl_baseline != USB_DEFAULT_BESL_UNSPECIFIED)
718 besl = USB_BESL_BASELINE_VALID |
719 USB_SET_BESL_BASELINE(dcd_config_params.besl_baseline);
720
721 if (dcd_config_params.besl_deep != USB_DEFAULT_BESL_UNSPECIFIED)
722 besl |= USB_BESL_DEEP_VALID |
723 USB_SET_BESL_DEEP(dcd_config_params.besl_deep);
724
725 /*
726 * A SuperSpeed device shall include the USB2.0 extension descriptor
727 * and shall support LPM when operating in USB2.0 HS mode.
728 */
729 usb_ext = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
730 bos->bNumDeviceCaps++;
731 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_EXT_CAP_SIZE);
732 usb_ext->bLength = USB_DT_USB_EXT_CAP_SIZE;
733 usb_ext->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
734 usb_ext->bDevCapabilityType = USB_CAP_TYPE_EXT;
735 usb_ext->bmAttributes = cpu_to_le32(USB_LPM_SUPPORT |
736 USB_BESL_SUPPORT | besl);
737
738 /*
739 * The Superspeed USB Capability descriptor shall be implemented by all
740 * SuperSpeed devices.
741 */
742 if (gadget_is_superspeed(cdev->gadget)) {
743 struct usb_ss_cap_descriptor *ss_cap;
744
745 ss_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
746 bos->bNumDeviceCaps++;
747 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SS_CAP_SIZE);
748 ss_cap->bLength = USB_DT_USB_SS_CAP_SIZE;
749 ss_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
750 ss_cap->bDevCapabilityType = USB_SS_CAP_TYPE;
751 ss_cap->bmAttributes = 0; /* LTM is not supported yet */
752 ss_cap->wSpeedSupported = cpu_to_le16(USB_LOW_SPEED_OPERATION |
753 USB_FULL_SPEED_OPERATION |
754 USB_HIGH_SPEED_OPERATION |
755 USB_5GBPS_OPERATION);
756 ss_cap->bFunctionalitySupport = USB_LOW_SPEED_OPERATION;
757 ss_cap->bU1devExitLat = dcd_config_params.bU1devExitLat;
758 ss_cap->bU2DevExitLat = dcd_config_params.bU2DevExitLat;
759 }
760
761 /* The SuperSpeedPlus USB Device Capability descriptor */
762 if (gadget_is_superspeed_plus(cdev->gadget)) {
763 struct usb_ssp_cap_descriptor *ssp_cap;
764 u8 ssac = 1;
765 u8 ssic;
766 int i;
767
768 if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x2)
769 ssac = 3;
770
771 /*
772 * Paired RX and TX sublink speed attributes share
773 * the same SSID.
774 */
775 ssic = (ssac + 1) / 2 - 1;
776
777 ssp_cap = cdev->req->buf + le16_to_cpu(bos->wTotalLength);
778 bos->bNumDeviceCaps++;
779
780 le16_add_cpu(&bos->wTotalLength, USB_DT_USB_SSP_CAP_SIZE(ssac));
781 ssp_cap->bLength = USB_DT_USB_SSP_CAP_SIZE(ssac);
782 ssp_cap->bDescriptorType = USB_DT_DEVICE_CAPABILITY;
783 ssp_cap->bDevCapabilityType = USB_SSP_CAP_TYPE;
784 ssp_cap->bReserved = 0;
785 ssp_cap->wReserved = 0;
786
787 ssp_cap->bmAttributes =
788 cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_ATTRIBS, ssac) |
789 FIELD_PREP(USB_SSP_SUBLINK_SPEED_IDS, ssic));
790
791 ssp_cap->wFunctionalitySupport =
792 cpu_to_le16(FIELD_PREP(USB_SSP_MIN_SUBLINK_SPEED_ATTRIBUTE_ID, 0) |
793 FIELD_PREP(USB_SSP_MIN_RX_LANE_COUNT, 1) |
794 FIELD_PREP(USB_SSP_MIN_TX_LANE_COUNT, 1));
795
796 /*
797 * Use 1 SSID if the gadget supports up to gen2x1 or not
798 * specified:
799 * - SSID 0 for symmetric RX/TX sublink speed of 10 Gbps.
800 *
801 * Use 1 SSID if the gadget supports up to gen1x2:
802 * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
803 *
804 * Use 2 SSIDs if the gadget supports up to gen2x2:
805 * - SSID 0 for symmetric RX/TX sublink speed of 5 Gbps.
806 * - SSID 1 for symmetric RX/TX sublink speed of 10 Gbps.
807 */
808 for (i = 0; i < ssac + 1; i++) {
809 u8 ssid;
810 u8 mantissa;
811 u8 type;
812
813 ssid = i >> 1;
814
815 if (cdev->gadget->max_ssp_rate == USB_SSP_GEN_2x1 ||
816 cdev->gadget->max_ssp_rate == USB_SSP_GEN_UNKNOWN)
817 mantissa = 10;
818 else
819 mantissa = 5 << ssid;
820
821 if (i % 2)
822 type = USB_SSP_SUBLINK_SPEED_ST_SYM_TX;
823 else
824 type = USB_SSP_SUBLINK_SPEED_ST_SYM_RX;
825
826 ssp_cap->bmSublinkSpeedAttr[i] =
827 cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, ssid) |
828 FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE,
829 USB_SSP_SUBLINK_SPEED_LSE_GBPS) |
830 FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST, type) |
831 FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP,
832 USB_SSP_SUBLINK_SPEED_LP_SSP) |
833 FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, mantissa));
834 }
835 }
836
837 return le16_to_cpu(bos->wTotalLength);
838 }
839
device_qual(struct usb_composite_dev * cdev)840 static void device_qual(struct usb_composite_dev *cdev)
841 {
842 struct usb_qualifier_descriptor *qual = cdev->req->buf;
843
844 qual->bLength = sizeof(*qual);
845 qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
846 /* POLICY: same bcdUSB and device type info at both speeds */
847 qual->bcdUSB = cdev->desc.bcdUSB;
848 qual->bDeviceClass = cdev->desc.bDeviceClass;
849 qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
850 qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
851 /* ASSUME same EP0 fifo size at both speeds */
852 qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
853 qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
854 qual->bRESERVED = 0;
855 }
856
857 /*-------------------------------------------------------------------------*/
858
reset_config(struct usb_composite_dev * cdev)859 static void reset_config(struct usb_composite_dev *cdev)
860 {
861 struct usb_function *f;
862
863 DBG(cdev, "reset config\n");
864
865 list_for_each_entry(f, &cdev->config->functions, list) {
866 if (f->disable)
867 f->disable(f);
868
869 bitmap_zero(f->endpoints, 32);
870 }
871 cdev->config = NULL;
872 cdev->delayed_status = 0;
873 }
874
set_config(struct usb_composite_dev * cdev,const struct usb_ctrlrequest * ctrl,unsigned number)875 static int set_config(struct usb_composite_dev *cdev,
876 const struct usb_ctrlrequest *ctrl, unsigned number)
877 {
878 struct usb_gadget *gadget = cdev->gadget;
879 struct usb_configuration *c = NULL;
880 int result = -EINVAL;
881 unsigned power = gadget_is_otg(gadget) ? 8 : 100;
882 int tmp;
883
884 if (number) {
885 list_for_each_entry(c, &cdev->configs, list) {
886 if (c->bConfigurationValue == number) {
887 /*
888 * We disable the FDs of the previous
889 * configuration only if the new configuration
890 * is a valid one
891 */
892 if (cdev->config)
893 reset_config(cdev);
894 result = 0;
895 break;
896 }
897 }
898 if (result < 0)
899 goto done;
900 } else { /* Zero configuration value - need to reset the config */
901 if (cdev->config)
902 reset_config(cdev);
903 result = 0;
904 }
905
906 DBG(cdev, "%s config #%d: %s\n",
907 usb_speed_string(gadget->speed),
908 number, c ? c->label : "unconfigured");
909
910 if (!c)
911 goto done;
912
913 usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
914 cdev->config = c;
915
916 /* Initialize all interfaces by setting them to altsetting zero. */
917 for (tmp = 0; tmp < MAX_CONFIG_INTERFACES; tmp++) {
918 struct usb_function *f = c->interface[tmp];
919 struct usb_descriptor_header **descriptors;
920
921 if (!f)
922 break;
923
924 /*
925 * Record which endpoints are used by the function. This is used
926 * to dispatch control requests targeted at that endpoint to the
927 * function's setup callback instead of the current
928 * configuration's setup callback.
929 */
930 descriptors = function_descriptors(f, gadget->speed);
931
932 for (; *descriptors; ++descriptors) {
933 struct usb_endpoint_descriptor *ep;
934 int addr;
935
936 if ((*descriptors)->bDescriptorType != USB_DT_ENDPOINT)
937 continue;
938
939 ep = (struct usb_endpoint_descriptor *)*descriptors;
940 addr = ((ep->bEndpointAddress & 0x80) >> 3)
941 | (ep->bEndpointAddress & 0x0f);
942 set_bit(addr, f->endpoints);
943 }
944
945 result = f->set_alt(f, tmp, 0);
946 if (result < 0) {
947 DBG(cdev, "interface %d (%s/%p) alt 0 --> %d\n",
948 tmp, f->name, f, result);
949
950 reset_config(cdev);
951 goto done;
952 }
953
954 if (result == USB_GADGET_DELAYED_STATUS) {
955 DBG(cdev,
956 "%s: interface %d (%s) requested delayed status\n",
957 __func__, tmp, f->name);
958 cdev->delayed_status++;
959 DBG(cdev, "delayed_status count %d\n",
960 cdev->delayed_status);
961 }
962 }
963
964 /* when we return, be sure our power usage is valid */
965 if (c->MaxPower || (c->bmAttributes & USB_CONFIG_ATT_SELFPOWER))
966 power = c->MaxPower;
967 else
968 power = CONFIG_USB_GADGET_VBUS_DRAW;
969
970 if (gadget->speed < USB_SPEED_SUPER)
971 power = min(power, 500U);
972 else
973 power = min(power, 900U);
974
975 if (USB_CONFIG_ATT_WAKEUP & c->bmAttributes)
976 usb_gadget_set_remote_wakeup(gadget, 1);
977 else
978 usb_gadget_set_remote_wakeup(gadget, 0);
979 done:
980 if (power <= USB_SELF_POWER_VBUS_MAX_DRAW)
981 usb_gadget_set_selfpowered(gadget);
982 else
983 usb_gadget_clear_selfpowered(gadget);
984
985 usb_gadget_vbus_draw(gadget, power);
986 if (result >= 0 && cdev->delayed_status)
987 result = USB_GADGET_DELAYED_STATUS;
988 return result;
989 }
990
usb_add_config_only(struct usb_composite_dev * cdev,struct usb_configuration * config)991 int usb_add_config_only(struct usb_composite_dev *cdev,
992 struct usb_configuration *config)
993 {
994 struct usb_configuration *c;
995
996 if (!config->bConfigurationValue)
997 return -EINVAL;
998
999 /* Prevent duplicate configuration identifiers */
1000 list_for_each_entry(c, &cdev->configs, list) {
1001 if (c->bConfigurationValue == config->bConfigurationValue)
1002 return -EBUSY;
1003 }
1004
1005 config->cdev = cdev;
1006 list_add_tail(&config->list, &cdev->configs);
1007
1008 INIT_LIST_HEAD(&config->functions);
1009 config->next_interface_id = 0;
1010 memset(config->interface, 0, sizeof(config->interface));
1011
1012 return 0;
1013 }
1014 EXPORT_SYMBOL_GPL(usb_add_config_only);
1015
1016 /**
1017 * usb_add_config() - add a configuration to a device.
1018 * @cdev: wraps the USB gadget
1019 * @config: the configuration, with bConfigurationValue assigned
1020 * @bind: the configuration's bind function
1021 * Context: single threaded during gadget setup
1022 *
1023 * One of the main tasks of a composite @bind() routine is to
1024 * add each of the configurations it supports, using this routine.
1025 *
1026 * This function returns the value of the configuration's @bind(), which
1027 * is zero for success else a negative errno value. Binding configurations
1028 * assigns global resources including string IDs, and per-configuration
1029 * resources such as interface IDs and endpoints.
1030 */
usb_add_config(struct usb_composite_dev * cdev,struct usb_configuration * config,int (* bind)(struct usb_configuration *))1031 int usb_add_config(struct usb_composite_dev *cdev,
1032 struct usb_configuration *config,
1033 int (*bind)(struct usb_configuration *))
1034 {
1035 int status = -EINVAL;
1036
1037 if (!bind)
1038 goto done;
1039
1040 DBG(cdev, "adding config #%u '%s'/%p\n",
1041 config->bConfigurationValue,
1042 config->label, config);
1043
1044 status = usb_add_config_only(cdev, config);
1045 if (status)
1046 goto done;
1047
1048 status = bind(config);
1049
1050 if (status == 0)
1051 status = usb_gadget_check_config(cdev->gadget);
1052
1053 if (status < 0) {
1054 while (!list_empty(&config->functions)) {
1055 struct usb_function *f;
1056
1057 f = list_first_entry(&config->functions,
1058 struct usb_function, list);
1059 list_del(&f->list);
1060 if (f->unbind) {
1061 DBG(cdev, "unbind function '%s'/%p\n",
1062 f->name, f);
1063 f->unbind(config, f);
1064 /* may free memory for "f" */
1065 }
1066 }
1067 list_del(&config->list);
1068 config->cdev = NULL;
1069 } else {
1070 unsigned i;
1071
1072 DBG(cdev, "cfg %d/%p speeds:%s%s%s%s\n",
1073 config->bConfigurationValue, config,
1074 config->superspeed_plus ? " superplus" : "",
1075 config->superspeed ? " super" : "",
1076 config->highspeed ? " high" : "",
1077 config->fullspeed
1078 ? (gadget_is_dualspeed(cdev->gadget)
1079 ? " full"
1080 : " full/low")
1081 : "");
1082
1083 for (i = 0; i < MAX_CONFIG_INTERFACES; i++) {
1084 struct usb_function *f = config->interface[i];
1085
1086 if (!f)
1087 continue;
1088 DBG(cdev, " interface %d = %s/%p\n",
1089 i, f->name, f);
1090 }
1091 }
1092
1093 /* set_alt(), or next bind(), sets up ep->claimed as needed */
1094 usb_ep_autoconfig_reset(cdev->gadget);
1095
1096 done:
1097 if (status)
1098 DBG(cdev, "added config '%s'/%u --> %d\n", config->label,
1099 config->bConfigurationValue, status);
1100 return status;
1101 }
1102 EXPORT_SYMBOL_GPL(usb_add_config);
1103
remove_config(struct usb_composite_dev * cdev,struct usb_configuration * config)1104 static void remove_config(struct usb_composite_dev *cdev,
1105 struct usb_configuration *config)
1106 {
1107 while (!list_empty(&config->functions)) {
1108 struct usb_function *f;
1109
1110 f = list_first_entry(&config->functions,
1111 struct usb_function, list);
1112
1113 usb_remove_function(config, f);
1114 }
1115 list_del(&config->list);
1116 if (config->unbind) {
1117 DBG(cdev, "unbind config '%s'/%p\n", config->label, config);
1118 config->unbind(config);
1119 /* may free memory for "c" */
1120 }
1121 }
1122
1123 /**
1124 * usb_remove_config() - remove a configuration from a device.
1125 * @cdev: wraps the USB gadget
1126 * @config: the configuration
1127 *
1128 * Drivers must call usb_gadget_disconnect before calling this function
1129 * to disconnect the device from the host and make sure the host will not
1130 * try to enumerate the device while we are changing the config list.
1131 */
usb_remove_config(struct usb_composite_dev * cdev,struct usb_configuration * config)1132 void usb_remove_config(struct usb_composite_dev *cdev,
1133 struct usb_configuration *config)
1134 {
1135 unsigned long flags;
1136
1137 spin_lock_irqsave(&cdev->lock, flags);
1138
1139 if (cdev->config == config)
1140 reset_config(cdev);
1141
1142 spin_unlock_irqrestore(&cdev->lock, flags);
1143
1144 remove_config(cdev, config);
1145 }
1146
1147 /*-------------------------------------------------------------------------*/
1148
1149 /* We support strings in multiple languages ... string descriptor zero
1150 * says which languages are supported. The typical case will be that
1151 * only one language (probably English) is used, with i18n handled on
1152 * the host side.
1153 */
1154
collect_langs(struct usb_gadget_strings ** sp,__le16 * buf)1155 static void collect_langs(struct usb_gadget_strings **sp, __le16 *buf)
1156 {
1157 const struct usb_gadget_strings *s;
1158 __le16 language;
1159 __le16 *tmp;
1160
1161 while (*sp) {
1162 s = *sp;
1163 language = cpu_to_le16(s->language);
1164 for (tmp = buf; *tmp && tmp < &buf[USB_MAX_STRING_LEN]; tmp++) {
1165 if (*tmp == language)
1166 goto repeat;
1167 }
1168 *tmp++ = language;
1169 repeat:
1170 sp++;
1171 }
1172 }
1173
lookup_string(struct usb_gadget_strings ** sp,void * buf,u16 language,int id)1174 static int lookup_string(
1175 struct usb_gadget_strings **sp,
1176 void *buf,
1177 u16 language,
1178 int id
1179 )
1180 {
1181 struct usb_gadget_strings *s;
1182 int value;
1183
1184 while (*sp) {
1185 s = *sp++;
1186 if (s->language != language)
1187 continue;
1188 value = usb_gadget_get_string(s, id, buf);
1189 if (value > 0)
1190 return value;
1191 }
1192 return -EINVAL;
1193 }
1194
get_string(struct usb_composite_dev * cdev,void * buf,u16 language,int id)1195 static int get_string(struct usb_composite_dev *cdev,
1196 void *buf, u16 language, int id)
1197 {
1198 struct usb_composite_driver *composite = cdev->driver;
1199 struct usb_gadget_string_container *uc;
1200 struct usb_configuration *c;
1201 struct usb_function *f;
1202 int len;
1203
1204 /* Yes, not only is USB's i18n support probably more than most
1205 * folk will ever care about ... also, it's all supported here.
1206 * (Except for UTF8 support for Unicode's "Astral Planes".)
1207 */
1208
1209 /* 0 == report all available language codes */
1210 if (id == 0) {
1211 struct usb_string_descriptor *s = buf;
1212 struct usb_gadget_strings **sp;
1213
1214 memset(s, 0, 256);
1215 s->bDescriptorType = USB_DT_STRING;
1216
1217 sp = composite->strings;
1218 if (sp)
1219 collect_langs(sp, s->wData);
1220
1221 list_for_each_entry(c, &cdev->configs, list) {
1222 sp = c->strings;
1223 if (sp)
1224 collect_langs(sp, s->wData);
1225
1226 list_for_each_entry(f, &c->functions, list) {
1227 sp = f->strings;
1228 if (sp)
1229 collect_langs(sp, s->wData);
1230 }
1231 }
1232 list_for_each_entry(uc, &cdev->gstrings, list) {
1233 struct usb_gadget_strings **sp;
1234
1235 sp = get_containers_gs(uc);
1236 collect_langs(sp, s->wData);
1237 }
1238
1239 for (len = 0; len <= USB_MAX_STRING_LEN && s->wData[len]; len++)
1240 continue;
1241 if (!len)
1242 return -EINVAL;
1243
1244 s->bLength = 2 * (len + 1);
1245 return s->bLength;
1246 }
1247
1248 if (cdev->use_os_string && language == 0 && id == OS_STRING_IDX) {
1249 struct usb_os_string *b = buf;
1250 b->bLength = sizeof(*b);
1251 b->bDescriptorType = USB_DT_STRING;
1252 compiletime_assert(
1253 sizeof(b->qwSignature) == sizeof(cdev->qw_sign),
1254 "qwSignature size must be equal to qw_sign");
1255 memcpy(&b->qwSignature, cdev->qw_sign, sizeof(b->qwSignature));
1256 b->bMS_VendorCode = cdev->b_vendor_code;
1257 b->bPad = 0;
1258 return sizeof(*b);
1259 }
1260
1261 list_for_each_entry(uc, &cdev->gstrings, list) {
1262 struct usb_gadget_strings **sp;
1263
1264 sp = get_containers_gs(uc);
1265 len = lookup_string(sp, buf, language, id);
1266 if (len > 0)
1267 return len;
1268 }
1269
1270 /* String IDs are device-scoped, so we look up each string
1271 * table we're told about. These lookups are infrequent;
1272 * simpler-is-better here.
1273 */
1274 if (composite->strings) {
1275 len = lookup_string(composite->strings, buf, language, id);
1276 if (len > 0)
1277 return len;
1278 }
1279 list_for_each_entry(c, &cdev->configs, list) {
1280 if (c->strings) {
1281 len = lookup_string(c->strings, buf, language, id);
1282 if (len > 0)
1283 return len;
1284 }
1285 list_for_each_entry(f, &c->functions, list) {
1286 if (!f->strings)
1287 continue;
1288 len = lookup_string(f->strings, buf, language, id);
1289 if (len > 0)
1290 return len;
1291 }
1292 }
1293 return -EINVAL;
1294 }
1295
1296 /**
1297 * usb_string_id() - allocate an unused string ID
1298 * @cdev: the device whose string descriptor IDs are being allocated
1299 * Context: single threaded during gadget setup
1300 *
1301 * @usb_string_id() is called from bind() callbacks to allocate
1302 * string IDs. Drivers for functions, configurations, or gadgets will
1303 * then store that ID in the appropriate descriptors and string table.
1304 *
1305 * All string identifier should be allocated using this,
1306 * @usb_string_ids_tab() or @usb_string_ids_n() routine, to ensure
1307 * that for example different functions don't wrongly assign different
1308 * meanings to the same identifier.
1309 */
usb_string_id(struct usb_composite_dev * cdev)1310 int usb_string_id(struct usb_composite_dev *cdev)
1311 {
1312 if (cdev->next_string_id < 254) {
1313 /* string id 0 is reserved by USB spec for list of
1314 * supported languages */
1315 /* 255 reserved as well? -- mina86 */
1316 cdev->next_string_id++;
1317 return cdev->next_string_id;
1318 }
1319 return -ENODEV;
1320 }
1321 EXPORT_SYMBOL_GPL(usb_string_id);
1322
1323 /**
1324 * usb_string_ids_tab() - allocate unused string IDs in batch
1325 * @cdev: the device whose string descriptor IDs are being allocated
1326 * @str: an array of usb_string objects to assign numbers to
1327 * Context: single threaded during gadget setup
1328 *
1329 * @usb_string_ids() is called from bind() callbacks to allocate
1330 * string IDs. Drivers for functions, configurations, or gadgets will
1331 * then copy IDs from the string table to the appropriate descriptors
1332 * and string table for other languages.
1333 *
1334 * All string identifier should be allocated using this,
1335 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1336 * example different functions don't wrongly assign different meanings
1337 * to the same identifier.
1338 */
usb_string_ids_tab(struct usb_composite_dev * cdev,struct usb_string * str)1339 int usb_string_ids_tab(struct usb_composite_dev *cdev, struct usb_string *str)
1340 {
1341 int next = cdev->next_string_id;
1342
1343 for (; str->s; ++str) {
1344 if (unlikely(next >= 254))
1345 return -ENODEV;
1346 str->id = ++next;
1347 }
1348
1349 cdev->next_string_id = next;
1350
1351 return 0;
1352 }
1353 EXPORT_SYMBOL_GPL(usb_string_ids_tab);
1354
copy_gadget_strings(struct usb_gadget_strings ** sp,unsigned n_gstrings,unsigned n_strings)1355 static struct usb_gadget_string_container *copy_gadget_strings(
1356 struct usb_gadget_strings **sp, unsigned n_gstrings,
1357 unsigned n_strings)
1358 {
1359 struct usb_gadget_string_container *uc;
1360 struct usb_gadget_strings **gs_array;
1361 struct usb_gadget_strings *gs;
1362 struct usb_string *s;
1363 unsigned mem;
1364 unsigned n_gs;
1365 unsigned n_s;
1366 void *stash;
1367
1368 mem = sizeof(*uc);
1369 mem += sizeof(void *) * (n_gstrings + 1);
1370 mem += sizeof(struct usb_gadget_strings) * n_gstrings;
1371 mem += sizeof(struct usb_string) * (n_strings + 1) * (n_gstrings);
1372 uc = kmalloc(mem, GFP_KERNEL);
1373 if (!uc)
1374 return ERR_PTR(-ENOMEM);
1375 gs_array = get_containers_gs(uc);
1376 stash = uc->stash;
1377 stash += sizeof(void *) * (n_gstrings + 1);
1378 for (n_gs = 0; n_gs < n_gstrings; n_gs++) {
1379 struct usb_string *org_s;
1380
1381 gs_array[n_gs] = stash;
1382 gs = gs_array[n_gs];
1383 stash += sizeof(struct usb_gadget_strings);
1384 gs->language = sp[n_gs]->language;
1385 gs->strings = stash;
1386 org_s = sp[n_gs]->strings;
1387
1388 for (n_s = 0; n_s < n_strings; n_s++) {
1389 s = stash;
1390 stash += sizeof(struct usb_string);
1391 if (org_s->s)
1392 s->s = org_s->s;
1393 else
1394 s->s = "";
1395 org_s++;
1396 }
1397 s = stash;
1398 s->s = NULL;
1399 stash += sizeof(struct usb_string);
1400
1401 }
1402 gs_array[n_gs] = NULL;
1403 return uc;
1404 }
1405
1406 /**
1407 * usb_gstrings_attach() - attach gadget strings to a cdev and assign ids
1408 * @cdev: the device whose string descriptor IDs are being allocated
1409 * and attached.
1410 * @sp: an array of usb_gadget_strings to attach.
1411 * @n_strings: number of entries in each usb_strings array (sp[]->strings)
1412 *
1413 * This function will create a deep copy of usb_gadget_strings and usb_string
1414 * and attach it to the cdev. The actual string (usb_string.s) will not be
1415 * copied but only a referenced will be made. The struct usb_gadget_strings
1416 * array may contain multiple languages and should be NULL terminated.
1417 * The ->language pointer of each struct usb_gadget_strings has to contain the
1418 * same amount of entries.
1419 * For instance: sp[0] is en-US, sp[1] is es-ES. It is expected that the first
1420 * usb_string entry of es-ES contains the translation of the first usb_string
1421 * entry of en-US. Therefore both entries become the same id assign.
1422 */
usb_gstrings_attach(struct usb_composite_dev * cdev,struct usb_gadget_strings ** sp,unsigned n_strings)1423 struct usb_string *usb_gstrings_attach(struct usb_composite_dev *cdev,
1424 struct usb_gadget_strings **sp, unsigned n_strings)
1425 {
1426 struct usb_gadget_string_container *uc;
1427 struct usb_gadget_strings **n_gs;
1428 unsigned n_gstrings = 0;
1429 unsigned i;
1430 int ret;
1431
1432 for (i = 0; sp[i]; i++)
1433 n_gstrings++;
1434
1435 if (!n_gstrings)
1436 return ERR_PTR(-EINVAL);
1437
1438 uc = copy_gadget_strings(sp, n_gstrings, n_strings);
1439 if (IS_ERR(uc))
1440 return ERR_CAST(uc);
1441
1442 n_gs = get_containers_gs(uc);
1443 ret = usb_string_ids_tab(cdev, n_gs[0]->strings);
1444 if (ret)
1445 goto err;
1446
1447 for (i = 1; i < n_gstrings; i++) {
1448 struct usb_string *m_s;
1449 struct usb_string *s;
1450 unsigned n;
1451
1452 m_s = n_gs[0]->strings;
1453 s = n_gs[i]->strings;
1454 for (n = 0; n < n_strings; n++) {
1455 s->id = m_s->id;
1456 s++;
1457 m_s++;
1458 }
1459 }
1460 list_add_tail(&uc->list, &cdev->gstrings);
1461 return n_gs[0]->strings;
1462 err:
1463 kfree(uc);
1464 return ERR_PTR(ret);
1465 }
1466 EXPORT_SYMBOL_GPL(usb_gstrings_attach);
1467
1468 /**
1469 * usb_string_ids_n() - allocate unused string IDs in batch
1470 * @c: the device whose string descriptor IDs are being allocated
1471 * @n: number of string IDs to allocate
1472 * Context: single threaded during gadget setup
1473 *
1474 * Returns the first requested ID. This ID and next @n-1 IDs are now
1475 * valid IDs. At least provided that @n is non-zero because if it
1476 * is, returns last requested ID which is now very useful information.
1477 *
1478 * @usb_string_ids_n() is called from bind() callbacks to allocate
1479 * string IDs. Drivers for functions, configurations, or gadgets will
1480 * then store that ID in the appropriate descriptors and string table.
1481 *
1482 * All string identifier should be allocated using this,
1483 * @usb_string_id() or @usb_string_ids_n() routine, to ensure that for
1484 * example different functions don't wrongly assign different meanings
1485 * to the same identifier.
1486 */
usb_string_ids_n(struct usb_composite_dev * c,unsigned n)1487 int usb_string_ids_n(struct usb_composite_dev *c, unsigned n)
1488 {
1489 unsigned next = c->next_string_id;
1490 if (unlikely(n > 254 || (unsigned)next + n > 254))
1491 return -ENODEV;
1492 c->next_string_id += n;
1493 return next + 1;
1494 }
1495 EXPORT_SYMBOL_GPL(usb_string_ids_n);
1496
1497 /*-------------------------------------------------------------------------*/
1498
composite_setup_complete(struct usb_ep * ep,struct usb_request * req)1499 static void composite_setup_complete(struct usb_ep *ep, struct usb_request *req)
1500 {
1501 struct usb_composite_dev *cdev;
1502
1503 if (req->status || req->actual != req->length)
1504 DBG((struct usb_composite_dev *) ep->driver_data,
1505 "setup complete --> %d, %d/%d\n",
1506 req->status, req->actual, req->length);
1507
1508 /*
1509 * REVIST The same ep0 requests are shared with function drivers
1510 * so they don't have to maintain the same ->complete() stubs.
1511 *
1512 * Because of that, we need to check for the validity of ->context
1513 * here, even though we know we've set it to something useful.
1514 */
1515 if (!req->context)
1516 return;
1517
1518 cdev = req->context;
1519
1520 if (cdev->req == req)
1521 cdev->setup_pending = false;
1522 else if (cdev->os_desc_req == req)
1523 cdev->os_desc_pending = false;
1524 else
1525 WARN(1, "unknown request %p\n", req);
1526 }
1527
composite_ep0_queue(struct usb_composite_dev * cdev,struct usb_request * req,gfp_t gfp_flags)1528 static int composite_ep0_queue(struct usb_composite_dev *cdev,
1529 struct usb_request *req, gfp_t gfp_flags)
1530 {
1531 int ret;
1532
1533 ret = usb_ep_queue(cdev->gadget->ep0, req, gfp_flags);
1534 if (ret == 0) {
1535 if (cdev->req == req)
1536 cdev->setup_pending = true;
1537 else if (cdev->os_desc_req == req)
1538 cdev->os_desc_pending = true;
1539 else
1540 WARN(1, "unknown request %p\n", req);
1541 }
1542
1543 return ret;
1544 }
1545
count_ext_compat(struct usb_configuration * c)1546 static int count_ext_compat(struct usb_configuration *c)
1547 {
1548 int i, res;
1549
1550 res = 0;
1551 for (i = 0; i < c->next_interface_id; ++i) {
1552 struct usb_function *f;
1553 int j;
1554
1555 f = c->interface[i];
1556 for (j = 0; j < f->os_desc_n; ++j) {
1557 struct usb_os_desc *d;
1558
1559 if (i != f->os_desc_table[j].if_id)
1560 continue;
1561 d = f->os_desc_table[j].os_desc;
1562 if (d && d->ext_compat_id)
1563 ++res;
1564 }
1565 }
1566 BUG_ON(res > 255);
1567 return res;
1568 }
1569
fill_ext_compat(struct usb_configuration * c,u8 * buf)1570 static int fill_ext_compat(struct usb_configuration *c, u8 *buf)
1571 {
1572 int i, count;
1573
1574 count = 16;
1575 buf += 16;
1576 for (i = 0; i < c->next_interface_id; ++i) {
1577 struct usb_function *f;
1578 int j;
1579
1580 f = c->interface[i];
1581 for (j = 0; j < f->os_desc_n; ++j) {
1582 struct usb_os_desc *d;
1583
1584 if (i != f->os_desc_table[j].if_id)
1585 continue;
1586 d = f->os_desc_table[j].os_desc;
1587 if (d && d->ext_compat_id) {
1588 *buf++ = i;
1589 *buf++ = 0x01;
1590 memcpy(buf, d->ext_compat_id, 16);
1591 buf += 22;
1592 } else {
1593 ++buf;
1594 *buf = 0x01;
1595 buf += 23;
1596 }
1597 count += 24;
1598 if (count + 24 >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1599 return count;
1600 }
1601 }
1602
1603 return count;
1604 }
1605
count_ext_prop(struct usb_configuration * c,int interface)1606 static int count_ext_prop(struct usb_configuration *c, int interface)
1607 {
1608 struct usb_function *f;
1609 int j;
1610
1611 f = c->interface[interface];
1612 for (j = 0; j < f->os_desc_n; ++j) {
1613 struct usb_os_desc *d;
1614
1615 if (interface != f->os_desc_table[j].if_id)
1616 continue;
1617 d = f->os_desc_table[j].os_desc;
1618 if (d && d->ext_compat_id)
1619 return d->ext_prop_count;
1620 }
1621 return 0;
1622 }
1623
len_ext_prop(struct usb_configuration * c,int interface)1624 static int len_ext_prop(struct usb_configuration *c, int interface)
1625 {
1626 struct usb_function *f;
1627 struct usb_os_desc *d;
1628 int j, res;
1629
1630 res = 10; /* header length */
1631 f = c->interface[interface];
1632 for (j = 0; j < f->os_desc_n; ++j) {
1633 if (interface != f->os_desc_table[j].if_id)
1634 continue;
1635 d = f->os_desc_table[j].os_desc;
1636 if (d)
1637 return min(res + d->ext_prop_len, 4096);
1638 }
1639 return res;
1640 }
1641
fill_ext_prop(struct usb_configuration * c,int interface,u8 * buf)1642 static int fill_ext_prop(struct usb_configuration *c, int interface, u8 *buf)
1643 {
1644 struct usb_function *f;
1645 struct usb_os_desc *d;
1646 struct usb_os_desc_ext_prop *ext_prop;
1647 int j, count, n, ret;
1648
1649 f = c->interface[interface];
1650 count = 10; /* header length */
1651 buf += 10;
1652 for (j = 0; j < f->os_desc_n; ++j) {
1653 if (interface != f->os_desc_table[j].if_id)
1654 continue;
1655 d = f->os_desc_table[j].os_desc;
1656 if (d)
1657 list_for_each_entry(ext_prop, &d->ext_prop, entry) {
1658 n = ext_prop->data_len +
1659 ext_prop->name_len + 14;
1660 if (count + n >= USB_COMP_EP0_OS_DESC_BUFSIZ)
1661 return count;
1662 usb_ext_prop_put_size(buf, n);
1663 usb_ext_prop_put_type(buf, ext_prop->type);
1664 ret = usb_ext_prop_put_name(buf, ext_prop->name,
1665 ext_prop->name_len);
1666 if (ret < 0)
1667 return ret;
1668 switch (ext_prop->type) {
1669 case USB_EXT_PROP_UNICODE:
1670 case USB_EXT_PROP_UNICODE_ENV:
1671 case USB_EXT_PROP_UNICODE_LINK:
1672 usb_ext_prop_put_unicode(buf, ret,
1673 ext_prop->data,
1674 ext_prop->data_len);
1675 break;
1676 case USB_EXT_PROP_BINARY:
1677 usb_ext_prop_put_binary(buf, ret,
1678 ext_prop->data,
1679 ext_prop->data_len);
1680 break;
1681 case USB_EXT_PROP_LE32:
1682 /* not implemented */
1683 case USB_EXT_PROP_BE32:
1684 /* not implemented */
1685 default:
1686 return -EINVAL;
1687 }
1688 buf += n;
1689 count += n;
1690 }
1691 }
1692
1693 return count;
1694 }
1695
1696 /*
1697 * The setup() callback implements all the ep0 functionality that's
1698 * not handled lower down, in hardware or the hardware driver(like
1699 * device and endpoint feature flags, and their status). It's all
1700 * housekeeping for the gadget function we're implementing. Most of
1701 * the work is in config and function specific setup.
1702 */
1703 int
composite_setup(struct usb_gadget * gadget,const struct usb_ctrlrequest * ctrl)1704 composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1705 {
1706 struct usb_composite_dev *cdev = get_gadget_data(gadget);
1707 struct usb_request *req = cdev->req;
1708 int value = -EOPNOTSUPP;
1709 int status = 0;
1710 u16 w_index = le16_to_cpu(ctrl->wIndex);
1711 u8 intf = w_index & 0xFF;
1712 u16 w_value = le16_to_cpu(ctrl->wValue);
1713 u16 w_length = le16_to_cpu(ctrl->wLength);
1714 struct usb_function *f = NULL;
1715 u8 endp;
1716
1717 if (w_length > USB_COMP_EP0_BUFSIZ) {
1718 if (ctrl->bRequestType & USB_DIR_IN) {
1719 /* Cast away the const, we are going to overwrite on purpose. */
1720 __le16 *temp = (__le16 *)&ctrl->wLength;
1721
1722 *temp = cpu_to_le16(USB_COMP_EP0_BUFSIZ);
1723 w_length = USB_COMP_EP0_BUFSIZ;
1724 } else {
1725 goto done;
1726 }
1727 }
1728
1729 /* partial re-init of the response message; the function or the
1730 * gadget might need to intercept e.g. a control-OUT completion
1731 * when we delegate to it.
1732 */
1733 req->zero = 0;
1734 req->context = cdev;
1735 req->complete = composite_setup_complete;
1736 req->length = 0;
1737 gadget->ep0->driver_data = cdev;
1738
1739 /*
1740 * Don't let non-standard requests match any of the cases below
1741 * by accident.
1742 */
1743 if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD)
1744 goto unknown;
1745
1746 switch (ctrl->bRequest) {
1747
1748 /* we handle all standard USB descriptors */
1749 case USB_REQ_GET_DESCRIPTOR:
1750 if (ctrl->bRequestType != USB_DIR_IN)
1751 goto unknown;
1752 switch (w_value >> 8) {
1753
1754 case USB_DT_DEVICE:
1755 cdev->desc.bNumConfigurations =
1756 count_configs(cdev, USB_DT_DEVICE);
1757 cdev->desc.bMaxPacketSize0 =
1758 cdev->gadget->ep0->maxpacket;
1759 if (gadget_is_superspeed(gadget)) {
1760 if (gadget->speed >= USB_SPEED_SUPER) {
1761 cdev->desc.bcdUSB = cpu_to_le16(0x0320);
1762 cdev->desc.bMaxPacketSize0 = 9;
1763 } else {
1764 cdev->desc.bcdUSB = cpu_to_le16(0x0210);
1765 }
1766 } else {
1767 if (gadget->lpm_capable)
1768 cdev->desc.bcdUSB = cpu_to_le16(0x0201);
1769 else
1770 cdev->desc.bcdUSB = cpu_to_le16(0x0200);
1771 }
1772
1773 value = min(w_length, (u16) sizeof cdev->desc);
1774 memcpy(req->buf, &cdev->desc, value);
1775 break;
1776 case USB_DT_DEVICE_QUALIFIER:
1777 if (!gadget_is_dualspeed(gadget) ||
1778 gadget->speed >= USB_SPEED_SUPER)
1779 break;
1780 device_qual(cdev);
1781 value = min_t(int, w_length,
1782 sizeof(struct usb_qualifier_descriptor));
1783 break;
1784 case USB_DT_OTHER_SPEED_CONFIG:
1785 if (!gadget_is_dualspeed(gadget) ||
1786 gadget->speed >= USB_SPEED_SUPER)
1787 break;
1788 fallthrough;
1789 case USB_DT_CONFIG:
1790 value = config_desc(cdev, w_value);
1791 if (value >= 0)
1792 value = min(w_length, (u16) value);
1793 break;
1794 case USB_DT_STRING:
1795 value = get_string(cdev, req->buf,
1796 w_index, w_value & 0xff);
1797 if (value >= 0)
1798 value = min(w_length, (u16) value);
1799 break;
1800 case USB_DT_BOS:
1801 if (gadget_is_superspeed(gadget) ||
1802 gadget->lpm_capable) {
1803 value = bos_desc(cdev);
1804 value = min(w_length, (u16) value);
1805 }
1806 break;
1807 case USB_DT_OTG:
1808 if (gadget_is_otg(gadget)) {
1809 struct usb_configuration *config;
1810 int otg_desc_len = 0;
1811
1812 if (cdev->config)
1813 config = cdev->config;
1814 else
1815 config = list_first_entry(
1816 &cdev->configs,
1817 struct usb_configuration, list);
1818 if (!config)
1819 goto done;
1820
1821 if (gadget->otg_caps &&
1822 (gadget->otg_caps->otg_rev >= 0x0200))
1823 otg_desc_len += sizeof(
1824 struct usb_otg20_descriptor);
1825 else
1826 otg_desc_len += sizeof(
1827 struct usb_otg_descriptor);
1828
1829 value = min_t(int, w_length, otg_desc_len);
1830 memcpy(req->buf, config->descriptors[0], value);
1831 }
1832 break;
1833 }
1834 break;
1835
1836 /* any number of configs can work */
1837 case USB_REQ_SET_CONFIGURATION:
1838 if (ctrl->bRequestType != 0)
1839 goto unknown;
1840 if (gadget_is_otg(gadget)) {
1841 if (gadget->a_hnp_support)
1842 DBG(cdev, "HNP available\n");
1843 else if (gadget->a_alt_hnp_support)
1844 DBG(cdev, "HNP on another port\n");
1845 else
1846 VDBG(cdev, "HNP inactive\n");
1847 }
1848 spin_lock(&cdev->lock);
1849 value = set_config(cdev, ctrl, w_value);
1850 spin_unlock(&cdev->lock);
1851 break;
1852 case USB_REQ_GET_CONFIGURATION:
1853 if (ctrl->bRequestType != USB_DIR_IN)
1854 goto unknown;
1855 if (cdev->config)
1856 *(u8 *)req->buf = cdev->config->bConfigurationValue;
1857 else
1858 *(u8 *)req->buf = 0;
1859 value = min(w_length, (u16) 1);
1860 break;
1861
1862 /* function drivers must handle get/set altsetting */
1863 case USB_REQ_SET_INTERFACE:
1864 if (ctrl->bRequestType != USB_RECIP_INTERFACE)
1865 goto unknown;
1866 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1867 break;
1868 f = cdev->config->interface[intf];
1869 if (!f)
1870 break;
1871
1872 /*
1873 * If there's no get_alt() method, we know only altsetting zero
1874 * works. There is no need to check if set_alt() is not NULL
1875 * as we check this in usb_add_function().
1876 */
1877 if (w_value && !f->get_alt)
1878 break;
1879
1880 spin_lock(&cdev->lock);
1881 value = f->set_alt(f, w_index, w_value);
1882 if (value == USB_GADGET_DELAYED_STATUS) {
1883 DBG(cdev,
1884 "%s: interface %d (%s) requested delayed status\n",
1885 __func__, intf, f->name);
1886 cdev->delayed_status++;
1887 DBG(cdev, "delayed_status count %d\n",
1888 cdev->delayed_status);
1889 }
1890 spin_unlock(&cdev->lock);
1891 break;
1892 case USB_REQ_GET_INTERFACE:
1893 if (ctrl->bRequestType != (USB_DIR_IN|USB_RECIP_INTERFACE))
1894 goto unknown;
1895 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1896 break;
1897 f = cdev->config->interface[intf];
1898 if (!f)
1899 break;
1900 /* lots of interfaces only need altsetting zero... */
1901 value = f->get_alt ? f->get_alt(f, w_index) : 0;
1902 if (value < 0)
1903 break;
1904 *((u8 *)req->buf) = value;
1905 value = min(w_length, (u16) 1);
1906 break;
1907 case USB_REQ_GET_STATUS:
1908 if (gadget_is_otg(gadget) && gadget->hnp_polling_support &&
1909 (w_index == OTG_STS_SELECTOR)) {
1910 if (ctrl->bRequestType != (USB_DIR_IN |
1911 USB_RECIP_DEVICE))
1912 goto unknown;
1913 *((u8 *)req->buf) = gadget->host_request_flag;
1914 value = 1;
1915 break;
1916 }
1917
1918 /*
1919 * USB 3.0 additions:
1920 * Function driver should handle get_status request. If such cb
1921 * wasn't supplied we respond with default value = 0
1922 * Note: function driver should supply such cb only for the
1923 * first interface of the function
1924 */
1925 if (!gadget_is_superspeed(gadget))
1926 goto unknown;
1927 if (ctrl->bRequestType != (USB_DIR_IN | USB_RECIP_INTERFACE))
1928 goto unknown;
1929 value = 2; /* This is the length of the get_status reply */
1930 put_unaligned_le16(0, req->buf);
1931 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1932 break;
1933 f = cdev->config->interface[intf];
1934 if (!f)
1935 break;
1936 status = f->get_status ? f->get_status(f) : 0;
1937 if (status < 0)
1938 break;
1939 put_unaligned_le16(status & 0x0000ffff, req->buf);
1940 break;
1941 /*
1942 * Function drivers should handle SetFeature/ClearFeature
1943 * (FUNCTION_SUSPEND) request. function_suspend cb should be supplied
1944 * only for the first interface of the function
1945 */
1946 case USB_REQ_CLEAR_FEATURE:
1947 case USB_REQ_SET_FEATURE:
1948 if (!gadget_is_superspeed(gadget))
1949 goto unknown;
1950 if (ctrl->bRequestType != (USB_DIR_OUT | USB_RECIP_INTERFACE))
1951 goto unknown;
1952 switch (w_value) {
1953 case USB_INTRF_FUNC_SUSPEND:
1954 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
1955 break;
1956 f = cdev->config->interface[intf];
1957 if (!f)
1958 break;
1959 value = 0;
1960 if (f->func_suspend)
1961 value = f->func_suspend(f, w_index >> 8);
1962 if (value < 0) {
1963 ERROR(cdev,
1964 "func_suspend() returned error %d\n",
1965 value);
1966 value = 0;
1967 }
1968 break;
1969 }
1970 break;
1971 default:
1972 unknown:
1973 /*
1974 * OS descriptors handling
1975 */
1976 if (cdev->use_os_string && cdev->os_desc_config &&
1977 (ctrl->bRequestType & USB_TYPE_VENDOR) &&
1978 ctrl->bRequest == cdev->b_vendor_code) {
1979 struct usb_configuration *os_desc_cfg;
1980 u8 *buf;
1981 int interface;
1982 int count = 0;
1983
1984 req = cdev->os_desc_req;
1985 req->context = cdev;
1986 req->complete = composite_setup_complete;
1987 buf = req->buf;
1988 os_desc_cfg = cdev->os_desc_config;
1989 w_length = min_t(u16, w_length, USB_COMP_EP0_OS_DESC_BUFSIZ);
1990 memset(buf, 0, w_length);
1991 buf[5] = 0x01;
1992 switch (ctrl->bRequestType & USB_RECIP_MASK) {
1993 case USB_RECIP_DEVICE:
1994 if (w_index != 0x4 || (w_value >> 8))
1995 break;
1996 buf[6] = w_index;
1997 /* Number of ext compat interfaces */
1998 count = count_ext_compat(os_desc_cfg);
1999 buf[8] = count;
2000 count *= 24; /* 24 B/ext compat desc */
2001 count += 16; /* header */
2002 put_unaligned_le32(count, buf);
2003 value = w_length;
2004 if (w_length > 0x10) {
2005 value = fill_ext_compat(os_desc_cfg, buf);
2006 value = min_t(u16, w_length, value);
2007 }
2008 break;
2009 case USB_RECIP_INTERFACE:
2010 if (w_index != 0x5 || (w_value >> 8))
2011 break;
2012 interface = w_value & 0xFF;
2013 if (interface >= MAX_CONFIG_INTERFACES ||
2014 !os_desc_cfg->interface[interface])
2015 break;
2016 buf[6] = w_index;
2017 count = count_ext_prop(os_desc_cfg,
2018 interface);
2019 put_unaligned_le16(count, buf + 8);
2020 count = len_ext_prop(os_desc_cfg,
2021 interface);
2022 put_unaligned_le32(count, buf);
2023 value = w_length;
2024 if (w_length > 0x0A) {
2025 value = fill_ext_prop(os_desc_cfg,
2026 interface, buf);
2027 if (value >= 0)
2028 value = min_t(u16, w_length, value);
2029 }
2030 break;
2031 }
2032
2033 goto check_value;
2034 }
2035
2036 VDBG(cdev,
2037 "non-core control req%02x.%02x v%04x i%04x l%d\n",
2038 ctrl->bRequestType, ctrl->bRequest,
2039 w_value, w_index, w_length);
2040
2041 /* functions always handle their interfaces and endpoints...
2042 * punt other recipients (other, WUSB, ...) to the current
2043 * configuration code.
2044 */
2045 if (cdev->config) {
2046 list_for_each_entry(f, &cdev->config->functions, list)
2047 if (f->req_match &&
2048 f->req_match(f, ctrl, false))
2049 goto try_fun_setup;
2050 } else {
2051 struct usb_configuration *c;
2052 list_for_each_entry(c, &cdev->configs, list)
2053 list_for_each_entry(f, &c->functions, list)
2054 if (f->req_match &&
2055 f->req_match(f, ctrl, true))
2056 goto try_fun_setup;
2057 }
2058 f = NULL;
2059
2060 switch (ctrl->bRequestType & USB_RECIP_MASK) {
2061 case USB_RECIP_INTERFACE:
2062 if (!cdev->config || intf >= MAX_CONFIG_INTERFACES)
2063 break;
2064 f = cdev->config->interface[intf];
2065 break;
2066
2067 case USB_RECIP_ENDPOINT:
2068 if (!cdev->config)
2069 break;
2070 endp = ((w_index & 0x80) >> 3) | (w_index & 0x0f);
2071 list_for_each_entry(f, &cdev->config->functions, list) {
2072 if (test_bit(endp, f->endpoints))
2073 break;
2074 }
2075 if (&f->list == &cdev->config->functions)
2076 f = NULL;
2077 break;
2078 }
2079 try_fun_setup:
2080 if (f && f->setup)
2081 value = f->setup(f, ctrl);
2082 else {
2083 struct usb_configuration *c;
2084
2085 c = cdev->config;
2086 if (!c)
2087 goto done;
2088
2089 /* try current config's setup */
2090 if (c->setup) {
2091 value = c->setup(c, ctrl);
2092 goto done;
2093 }
2094
2095 /* try the only function in the current config */
2096 if (!list_is_singular(&c->functions))
2097 goto done;
2098 f = list_first_entry(&c->functions, struct usb_function,
2099 list);
2100 if (f->setup)
2101 value = f->setup(f, ctrl);
2102 }
2103
2104 goto done;
2105 }
2106
2107 check_value:
2108 /* respond with data transfer before status phase? */
2109 if (value >= 0 && value != USB_GADGET_DELAYED_STATUS) {
2110 req->length = value;
2111 req->context = cdev;
2112 req->zero = value < w_length;
2113 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2114 if (value < 0) {
2115 DBG(cdev, "ep_queue --> %d\n", value);
2116 req->status = 0;
2117 composite_setup_complete(gadget->ep0, req);
2118 }
2119 } else if (value == USB_GADGET_DELAYED_STATUS && w_length != 0) {
2120 WARN(cdev,
2121 "%s: Delayed status not supported for w_length != 0",
2122 __func__);
2123 }
2124
2125 done:
2126 /* device either stalls (value < 0) or reports success */
2127 return value;
2128 }
2129
__composite_disconnect(struct usb_gadget * gadget)2130 static void __composite_disconnect(struct usb_gadget *gadget)
2131 {
2132 struct usb_composite_dev *cdev = get_gadget_data(gadget);
2133 unsigned long flags;
2134
2135 /* REVISIT: should we have config and device level
2136 * disconnect callbacks?
2137 */
2138 spin_lock_irqsave(&cdev->lock, flags);
2139 cdev->suspended = 0;
2140 if (cdev->config)
2141 reset_config(cdev);
2142 if (cdev->driver->disconnect)
2143 cdev->driver->disconnect(cdev);
2144 spin_unlock_irqrestore(&cdev->lock, flags);
2145 }
2146
composite_disconnect(struct usb_gadget * gadget)2147 void composite_disconnect(struct usb_gadget *gadget)
2148 {
2149 usb_gadget_vbus_draw(gadget, 0);
2150 __composite_disconnect(gadget);
2151 }
2152
composite_reset(struct usb_gadget * gadget)2153 void composite_reset(struct usb_gadget *gadget)
2154 {
2155 /*
2156 * Section 1.4.13 Standard Downstream Port of the USB battery charging
2157 * specification v1.2 states that a device connected on a SDP shall only
2158 * draw at max 100mA while in a connected, but unconfigured state.
2159 */
2160 usb_gadget_vbus_draw(gadget, 100);
2161 __composite_disconnect(gadget);
2162 }
2163
2164 /*-------------------------------------------------------------------------*/
2165
suspended_show(struct device * dev,struct device_attribute * attr,char * buf)2166 static ssize_t suspended_show(struct device *dev, struct device_attribute *attr,
2167 char *buf)
2168 {
2169 struct usb_gadget *gadget = dev_to_usb_gadget(dev);
2170 struct usb_composite_dev *cdev = get_gadget_data(gadget);
2171
2172 return sprintf(buf, "%d\n", cdev->suspended);
2173 }
2174 static DEVICE_ATTR_RO(suspended);
2175
__composite_unbind(struct usb_gadget * gadget,bool unbind_driver)2176 static void __composite_unbind(struct usb_gadget *gadget, bool unbind_driver)
2177 {
2178 struct usb_composite_dev *cdev = get_gadget_data(gadget);
2179 struct usb_gadget_strings *gstr = cdev->driver->strings[0];
2180 struct usb_string *dev_str = gstr->strings;
2181
2182 /* composite_disconnect() must already have been called
2183 * by the underlying peripheral controller driver!
2184 * so there's no i/o concurrency that could affect the
2185 * state protected by cdev->lock.
2186 */
2187 WARN_ON(cdev->config);
2188
2189 while (!list_empty(&cdev->configs)) {
2190 struct usb_configuration *c;
2191 c = list_first_entry(&cdev->configs,
2192 struct usb_configuration, list);
2193 remove_config(cdev, c);
2194 }
2195 if (cdev->driver->unbind && unbind_driver)
2196 cdev->driver->unbind(cdev);
2197
2198 composite_dev_cleanup(cdev);
2199
2200 if (dev_str[USB_GADGET_MANUFACTURER_IDX].s == cdev->def_manufacturer)
2201 dev_str[USB_GADGET_MANUFACTURER_IDX].s = "";
2202
2203 kfree(cdev->def_manufacturer);
2204 kfree(cdev);
2205 set_gadget_data(gadget, NULL);
2206 }
2207
composite_unbind(struct usb_gadget * gadget)2208 static void composite_unbind(struct usb_gadget *gadget)
2209 {
2210 __composite_unbind(gadget, true);
2211 }
2212
update_unchanged_dev_desc(struct usb_device_descriptor * new,const struct usb_device_descriptor * old)2213 static void update_unchanged_dev_desc(struct usb_device_descriptor *new,
2214 const struct usb_device_descriptor *old)
2215 {
2216 __le16 idVendor;
2217 __le16 idProduct;
2218 __le16 bcdDevice;
2219 u8 iSerialNumber;
2220 u8 iManufacturer;
2221 u8 iProduct;
2222
2223 /*
2224 * these variables may have been set in
2225 * usb_composite_overwrite_options()
2226 */
2227 idVendor = new->idVendor;
2228 idProduct = new->idProduct;
2229 bcdDevice = new->bcdDevice;
2230 iSerialNumber = new->iSerialNumber;
2231 iManufacturer = new->iManufacturer;
2232 iProduct = new->iProduct;
2233
2234 *new = *old;
2235 if (idVendor)
2236 new->idVendor = idVendor;
2237 if (idProduct)
2238 new->idProduct = idProduct;
2239 if (bcdDevice)
2240 new->bcdDevice = bcdDevice;
2241 else
2242 new->bcdDevice = cpu_to_le16(get_default_bcdDevice());
2243 if (iSerialNumber)
2244 new->iSerialNumber = iSerialNumber;
2245 if (iManufacturer)
2246 new->iManufacturer = iManufacturer;
2247 if (iProduct)
2248 new->iProduct = iProduct;
2249 }
2250
composite_dev_prepare(struct usb_composite_driver * composite,struct usb_composite_dev * cdev)2251 int composite_dev_prepare(struct usb_composite_driver *composite,
2252 struct usb_composite_dev *cdev)
2253 {
2254 struct usb_gadget *gadget = cdev->gadget;
2255 int ret = -ENOMEM;
2256
2257 /* preallocate control response and buffer */
2258 cdev->req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
2259 if (!cdev->req)
2260 return -ENOMEM;
2261
2262 cdev->req->buf = kzalloc(USB_COMP_EP0_BUFSIZ, GFP_KERNEL);
2263 if (!cdev->req->buf)
2264 goto fail;
2265
2266 ret = device_create_file(&gadget->dev, &dev_attr_suspended);
2267 if (ret)
2268 goto fail_dev;
2269
2270 cdev->req->complete = composite_setup_complete;
2271 cdev->req->context = cdev;
2272 gadget->ep0->driver_data = cdev;
2273
2274 cdev->driver = composite;
2275
2276 /*
2277 * As per USB compliance update, a device that is actively drawing
2278 * more than 100mA from USB must report itself as bus-powered in
2279 * the GetStatus(DEVICE) call.
2280 */
2281 if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
2282 usb_gadget_set_selfpowered(gadget);
2283
2284 /* interface and string IDs start at zero via kzalloc.
2285 * we force endpoints to start unassigned; few controller
2286 * drivers will zero ep->driver_data.
2287 */
2288 usb_ep_autoconfig_reset(gadget);
2289 return 0;
2290 fail_dev:
2291 kfree(cdev->req->buf);
2292 fail:
2293 usb_ep_free_request(gadget->ep0, cdev->req);
2294 cdev->req = NULL;
2295 return ret;
2296 }
2297
composite_os_desc_req_prepare(struct usb_composite_dev * cdev,struct usb_ep * ep0)2298 int composite_os_desc_req_prepare(struct usb_composite_dev *cdev,
2299 struct usb_ep *ep0)
2300 {
2301 int ret = 0;
2302
2303 cdev->os_desc_req = usb_ep_alloc_request(ep0, GFP_KERNEL);
2304 if (!cdev->os_desc_req) {
2305 ret = -ENOMEM;
2306 goto end;
2307 }
2308
2309 cdev->os_desc_req->buf = kmalloc(USB_COMP_EP0_OS_DESC_BUFSIZ,
2310 GFP_KERNEL);
2311 if (!cdev->os_desc_req->buf) {
2312 ret = -ENOMEM;
2313 usb_ep_free_request(ep0, cdev->os_desc_req);
2314 goto end;
2315 }
2316 cdev->os_desc_req->context = cdev;
2317 cdev->os_desc_req->complete = composite_setup_complete;
2318 end:
2319 return ret;
2320 }
2321
composite_dev_cleanup(struct usb_composite_dev * cdev)2322 void composite_dev_cleanup(struct usb_composite_dev *cdev)
2323 {
2324 struct usb_gadget_string_container *uc, *tmp;
2325 struct usb_ep *ep, *tmp_ep;
2326
2327 list_for_each_entry_safe(uc, tmp, &cdev->gstrings, list) {
2328 list_del(&uc->list);
2329 kfree(uc);
2330 }
2331 if (cdev->os_desc_req) {
2332 if (cdev->os_desc_pending)
2333 usb_ep_dequeue(cdev->gadget->ep0, cdev->os_desc_req);
2334
2335 kfree(cdev->os_desc_req->buf);
2336 cdev->os_desc_req->buf = NULL;
2337 usb_ep_free_request(cdev->gadget->ep0, cdev->os_desc_req);
2338 cdev->os_desc_req = NULL;
2339 }
2340 if (cdev->req) {
2341 if (cdev->setup_pending)
2342 usb_ep_dequeue(cdev->gadget->ep0, cdev->req);
2343
2344 kfree(cdev->req->buf);
2345 cdev->req->buf = NULL;
2346 usb_ep_free_request(cdev->gadget->ep0, cdev->req);
2347 cdev->req = NULL;
2348 }
2349 cdev->next_string_id = 0;
2350 device_remove_file(&cdev->gadget->dev, &dev_attr_suspended);
2351
2352 /*
2353 * Some UDC backends have a dynamic EP allocation scheme.
2354 *
2355 * In that case, the dispose() callback is used to notify the
2356 * backend that the EPs are no longer in use.
2357 *
2358 * Note: The UDC backend can remove the EP from the ep_list as
2359 * a result, so we need to use the _safe list iterator.
2360 */
2361 list_for_each_entry_safe(ep, tmp_ep,
2362 &cdev->gadget->ep_list, ep_list) {
2363 if (ep->ops->dispose)
2364 ep->ops->dispose(ep);
2365 }
2366 }
2367
composite_bind(struct usb_gadget * gadget,struct usb_gadget_driver * gdriver)2368 static int composite_bind(struct usb_gadget *gadget,
2369 struct usb_gadget_driver *gdriver)
2370 {
2371 struct usb_composite_dev *cdev;
2372 struct usb_composite_driver *composite = to_cdriver(gdriver);
2373 int status = -ENOMEM;
2374
2375 cdev = kzalloc(sizeof *cdev, GFP_KERNEL);
2376 if (!cdev)
2377 return status;
2378
2379 spin_lock_init(&cdev->lock);
2380 cdev->gadget = gadget;
2381 set_gadget_data(gadget, cdev);
2382 INIT_LIST_HEAD(&cdev->configs);
2383 INIT_LIST_HEAD(&cdev->gstrings);
2384
2385 status = composite_dev_prepare(composite, cdev);
2386 if (status)
2387 goto fail;
2388
2389 /* composite gadget needs to assign strings for whole device (like
2390 * serial number), register function drivers, potentially update
2391 * power state and consumption, etc
2392 */
2393 status = composite->bind(cdev);
2394 if (status < 0)
2395 goto fail;
2396
2397 if (cdev->use_os_string) {
2398 status = composite_os_desc_req_prepare(cdev, gadget->ep0);
2399 if (status)
2400 goto fail;
2401 }
2402
2403 update_unchanged_dev_desc(&cdev->desc, composite->dev);
2404
2405 /* has userspace failed to provide a serial number? */
2406 if (composite->needs_serial && !cdev->desc.iSerialNumber)
2407 WARNING(cdev, "userspace failed to provide iSerialNumber\n");
2408
2409 INFO(cdev, "%s ready\n", composite->name);
2410 return 0;
2411
2412 fail:
2413 __composite_unbind(gadget, false);
2414 return status;
2415 }
2416
2417 /*-------------------------------------------------------------------------*/
2418
composite_suspend(struct usb_gadget * gadget)2419 void composite_suspend(struct usb_gadget *gadget)
2420 {
2421 struct usb_composite_dev *cdev = get_gadget_data(gadget);
2422 struct usb_function *f;
2423
2424 /* REVISIT: should we have config level
2425 * suspend/resume callbacks?
2426 */
2427 DBG(cdev, "suspend\n");
2428 if (cdev->config) {
2429 list_for_each_entry(f, &cdev->config->functions, list) {
2430 if (f->suspend)
2431 f->suspend(f);
2432 }
2433 }
2434 if (cdev->driver->suspend)
2435 cdev->driver->suspend(cdev);
2436
2437 cdev->suspended = 1;
2438
2439 usb_gadget_set_selfpowered(gadget);
2440 usb_gadget_vbus_draw(gadget, 2);
2441 }
2442
composite_resume(struct usb_gadget * gadget)2443 void composite_resume(struct usb_gadget *gadget)
2444 {
2445 struct usb_composite_dev *cdev = get_gadget_data(gadget);
2446 struct usb_function *f;
2447 unsigned maxpower;
2448
2449 /* REVISIT: should we have config level
2450 * suspend/resume callbacks?
2451 */
2452 DBG(cdev, "resume\n");
2453 if (cdev->driver->resume)
2454 cdev->driver->resume(cdev);
2455 if (cdev->config) {
2456 list_for_each_entry(f, &cdev->config->functions, list) {
2457 if (f->resume)
2458 f->resume(f);
2459 }
2460
2461 maxpower = cdev->config->MaxPower ?
2462 cdev->config->MaxPower : CONFIG_USB_GADGET_VBUS_DRAW;
2463 if (gadget->speed < USB_SPEED_SUPER)
2464 maxpower = min(maxpower, 500U);
2465 else
2466 maxpower = min(maxpower, 900U);
2467
2468 if (maxpower > USB_SELF_POWER_VBUS_MAX_DRAW)
2469 usb_gadget_clear_selfpowered(gadget);
2470
2471 usb_gadget_vbus_draw(gadget, maxpower);
2472 }
2473
2474 cdev->suspended = 0;
2475 }
2476
2477 /*-------------------------------------------------------------------------*/
2478
2479 static const struct usb_gadget_driver composite_driver_template = {
2480 .bind = composite_bind,
2481 .unbind = composite_unbind,
2482
2483 .setup = composite_setup,
2484 .reset = composite_reset,
2485 .disconnect = composite_disconnect,
2486
2487 .suspend = composite_suspend,
2488 .resume = composite_resume,
2489
2490 .driver = {
2491 .owner = THIS_MODULE,
2492 },
2493 };
2494
2495 /**
2496 * usb_composite_probe() - register a composite driver
2497 * @driver: the driver to register
2498 *
2499 * Context: single threaded during gadget setup
2500 *
2501 * This function is used to register drivers using the composite driver
2502 * framework. The return value is zero, or a negative errno value.
2503 * Those values normally come from the driver's @bind method, which does
2504 * all the work of setting up the driver to match the hardware.
2505 *
2506 * On successful return, the gadget is ready to respond to requests from
2507 * the host, unless one of its components invokes usb_gadget_disconnect()
2508 * while it was binding. That would usually be done in order to wait for
2509 * some userspace participation.
2510 */
usb_composite_probe(struct usb_composite_driver * driver)2511 int usb_composite_probe(struct usb_composite_driver *driver)
2512 {
2513 struct usb_gadget_driver *gadget_driver;
2514
2515 if (!driver || !driver->dev || !driver->bind)
2516 return -EINVAL;
2517
2518 if (!driver->name)
2519 driver->name = "composite";
2520
2521 driver->gadget_driver = composite_driver_template;
2522 gadget_driver = &driver->gadget_driver;
2523
2524 gadget_driver->function = (char *) driver->name;
2525 gadget_driver->driver.name = driver->name;
2526 gadget_driver->max_speed = driver->max_speed;
2527
2528 return usb_gadget_probe_driver(gadget_driver);
2529 }
2530 EXPORT_SYMBOL_GPL(usb_composite_probe);
2531
2532 /**
2533 * usb_composite_unregister() - unregister a composite driver
2534 * @driver: the driver to unregister
2535 *
2536 * This function is used to unregister drivers using the composite
2537 * driver framework.
2538 */
usb_composite_unregister(struct usb_composite_driver * driver)2539 void usb_composite_unregister(struct usb_composite_driver *driver)
2540 {
2541 usb_gadget_unregister_driver(&driver->gadget_driver);
2542 }
2543 EXPORT_SYMBOL_GPL(usb_composite_unregister);
2544
2545 /**
2546 * usb_composite_setup_continue() - Continue with the control transfer
2547 * @cdev: the composite device who's control transfer was kept waiting
2548 *
2549 * This function must be called by the USB function driver to continue
2550 * with the control transfer's data/status stage in case it had requested to
2551 * delay the data/status stages. A USB function's setup handler (e.g. set_alt())
2552 * can request the composite framework to delay the setup request's data/status
2553 * stages by returning USB_GADGET_DELAYED_STATUS.
2554 */
usb_composite_setup_continue(struct usb_composite_dev * cdev)2555 void usb_composite_setup_continue(struct usb_composite_dev *cdev)
2556 {
2557 int value;
2558 struct usb_request *req = cdev->req;
2559 unsigned long flags;
2560
2561 DBG(cdev, "%s\n", __func__);
2562 spin_lock_irqsave(&cdev->lock, flags);
2563
2564 if (cdev->delayed_status == 0) {
2565 WARN(cdev, "%s: Unexpected call\n", __func__);
2566
2567 } else if (--cdev->delayed_status == 0) {
2568 DBG(cdev, "%s: Completing delayed status\n", __func__);
2569 req->length = 0;
2570 req->context = cdev;
2571 value = composite_ep0_queue(cdev, req, GFP_ATOMIC);
2572 if (value < 0) {
2573 DBG(cdev, "ep_queue --> %d\n", value);
2574 req->status = 0;
2575 composite_setup_complete(cdev->gadget->ep0, req);
2576 }
2577 }
2578
2579 spin_unlock_irqrestore(&cdev->lock, flags);
2580 }
2581 EXPORT_SYMBOL_GPL(usb_composite_setup_continue);
2582
composite_default_mfr(struct usb_gadget * gadget)2583 static char *composite_default_mfr(struct usb_gadget *gadget)
2584 {
2585 return kasprintf(GFP_KERNEL, "%s %s with %s", init_utsname()->sysname,
2586 init_utsname()->release, gadget->name);
2587 }
2588
usb_composite_overwrite_options(struct usb_composite_dev * cdev,struct usb_composite_overwrite * covr)2589 void usb_composite_overwrite_options(struct usb_composite_dev *cdev,
2590 struct usb_composite_overwrite *covr)
2591 {
2592 struct usb_device_descriptor *desc = &cdev->desc;
2593 struct usb_gadget_strings *gstr = cdev->driver->strings[0];
2594 struct usb_string *dev_str = gstr->strings;
2595
2596 if (covr->idVendor)
2597 desc->idVendor = cpu_to_le16(covr->idVendor);
2598
2599 if (covr->idProduct)
2600 desc->idProduct = cpu_to_le16(covr->idProduct);
2601
2602 if (covr->bcdDevice)
2603 desc->bcdDevice = cpu_to_le16(covr->bcdDevice);
2604
2605 if (covr->serial_number) {
2606 desc->iSerialNumber = dev_str[USB_GADGET_SERIAL_IDX].id;
2607 dev_str[USB_GADGET_SERIAL_IDX].s = covr->serial_number;
2608 }
2609 if (covr->manufacturer) {
2610 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2611 dev_str[USB_GADGET_MANUFACTURER_IDX].s = covr->manufacturer;
2612
2613 } else if (!strlen(dev_str[USB_GADGET_MANUFACTURER_IDX].s)) {
2614 desc->iManufacturer = dev_str[USB_GADGET_MANUFACTURER_IDX].id;
2615 cdev->def_manufacturer = composite_default_mfr(cdev->gadget);
2616 dev_str[USB_GADGET_MANUFACTURER_IDX].s = cdev->def_manufacturer;
2617 }
2618
2619 if (covr->product) {
2620 desc->iProduct = dev_str[USB_GADGET_PRODUCT_IDX].id;
2621 dev_str[USB_GADGET_PRODUCT_IDX].s = covr->product;
2622 }
2623 }
2624 EXPORT_SYMBOL_GPL(usb_composite_overwrite_options);
2625
2626 MODULE_LICENSE("GPL");
2627 MODULE_AUTHOR("David Brownell");
2628