xref: /openbmc/linux/drivers/usb/gadget/udc/dummy_hcd.c (revision 5ed132db5ad4f58156ae9d28219396b6f764a9cb)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * dummy_hcd.c -- Dummy/Loopback USB host and device emulator driver.
4  *
5  * Maintainer: Alan Stern <stern@rowland.harvard.edu>
6  *
7  * Copyright (C) 2003 David Brownell
8  * Copyright (C) 2003-2005 Alan Stern
9  */
10 
11 
12 /*
13  * This exposes a device side "USB gadget" API, driven by requests to a
14  * Linux-USB host controller driver.  USB traffic is simulated; there's
15  * no need for USB hardware.  Use this with two other drivers:
16  *
17  *  - Gadget driver, responding to requests (device);
18  *  - Host-side device driver, as already familiar in Linux.
19  *
20  * Having this all in one kernel can help some stages of development,
21  * bypassing some hardware (and driver) issues.  UML could help too.
22  *
23  * Note: The emulation does not include isochronous transfers!
24  */
25 
26 #include <linux/module.h>
27 #include <linux/kernel.h>
28 #include <linux/delay.h>
29 #include <linux/ioport.h>
30 #include <linux/slab.h>
31 #include <linux/errno.h>
32 #include <linux/init.h>
33 #include <linux/timer.h>
34 #include <linux/list.h>
35 #include <linux/interrupt.h>
36 #include <linux/platform_device.h>
37 #include <linux/usb.h>
38 #include <linux/usb/gadget.h>
39 #include <linux/usb/hcd.h>
40 #include <linux/scatterlist.h>
41 
42 #include <asm/byteorder.h>
43 #include <linux/io.h>
44 #include <asm/irq.h>
45 #include <asm/unaligned.h>
46 
47 #define DRIVER_DESC	"USB Host+Gadget Emulator"
48 #define DRIVER_VERSION	"02 May 2005"
49 
50 #define POWER_BUDGET	500	/* in mA; use 8 for low-power port testing */
51 #define POWER_BUDGET_3	900	/* in mA */
52 
53 static const char	driver_name[] = "dummy_hcd";
54 static const char	driver_desc[] = "USB Host+Gadget Emulator";
55 
56 static const char	gadget_name[] = "dummy_udc";
57 
58 MODULE_DESCRIPTION(DRIVER_DESC);
59 MODULE_AUTHOR("David Brownell");
60 MODULE_LICENSE("GPL");
61 
62 struct dummy_hcd_module_parameters {
63 	bool is_super_speed;
64 	bool is_high_speed;
65 	unsigned int num;
66 };
67 
68 static struct dummy_hcd_module_parameters mod_data = {
69 	.is_super_speed = false,
70 	.is_high_speed = true,
71 	.num = 1,
72 };
73 module_param_named(is_super_speed, mod_data.is_super_speed, bool, S_IRUGO);
74 MODULE_PARM_DESC(is_super_speed, "true to simulate SuperSpeed connection");
75 module_param_named(is_high_speed, mod_data.is_high_speed, bool, S_IRUGO);
76 MODULE_PARM_DESC(is_high_speed, "true to simulate HighSpeed connection");
77 module_param_named(num, mod_data.num, uint, S_IRUGO);
78 MODULE_PARM_DESC(num, "number of emulated controllers");
79 /*-------------------------------------------------------------------------*/
80 
81 /* gadget side driver data structres */
82 struct dummy_ep {
83 	struct list_head		queue;
84 	unsigned long			last_io;	/* jiffies timestamp */
85 	struct usb_gadget		*gadget;
86 	const struct usb_endpoint_descriptor *desc;
87 	struct usb_ep			ep;
88 	unsigned			halted:1;
89 	unsigned			wedged:1;
90 	unsigned			already_seen:1;
91 	unsigned			setup_stage:1;
92 	unsigned			stream_en:1;
93 };
94 
95 struct dummy_request {
96 	struct list_head		queue;		/* ep's requests */
97 	struct usb_request		req;
98 };
99 
100 static inline struct dummy_ep *usb_ep_to_dummy_ep(struct usb_ep *_ep)
101 {
102 	return container_of(_ep, struct dummy_ep, ep);
103 }
104 
105 static inline struct dummy_request *usb_request_to_dummy_request
106 		(struct usb_request *_req)
107 {
108 	return container_of(_req, struct dummy_request, req);
109 }
110 
111 /*-------------------------------------------------------------------------*/
112 
113 /*
114  * Every device has ep0 for control requests, plus up to 30 more endpoints,
115  * in one of two types:
116  *
117  *   - Configurable:  direction (in/out), type (bulk, iso, etc), and endpoint
118  *     number can be changed.  Names like "ep-a" are used for this type.
119  *
120  *   - Fixed Function:  in other cases.  some characteristics may be mutable;
121  *     that'd be hardware-specific.  Names like "ep12out-bulk" are used.
122  *
123  * Gadget drivers are responsible for not setting up conflicting endpoint
124  * configurations, illegal or unsupported packet lengths, and so on.
125  */
126 
127 static const char ep0name[] = "ep0";
128 
129 static const struct {
130 	const char *name;
131 	const struct usb_ep_caps caps;
132 } ep_info[] = {
133 #define EP_INFO(_name, _caps) \
134 	{ \
135 		.name = _name, \
136 		.caps = _caps, \
137 	}
138 
139 /* we don't provide isochronous endpoints since we don't support them */
140 #define TYPE_BULK_OR_INT	(USB_EP_CAPS_TYPE_BULK | USB_EP_CAPS_TYPE_INT)
141 
142 	/* everyone has ep0 */
143 	EP_INFO(ep0name,
144 		USB_EP_CAPS(USB_EP_CAPS_TYPE_CONTROL, USB_EP_CAPS_DIR_ALL)),
145 	/* act like a pxa250: fifteen fixed function endpoints */
146 	EP_INFO("ep1in-bulk",
147 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_IN)),
148 	EP_INFO("ep2out-bulk",
149 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_OUT)),
150 /*
151 	EP_INFO("ep3in-iso",
152 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_IN)),
153 	EP_INFO("ep4out-iso",
154 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_OUT)),
155 */
156 	EP_INFO("ep5in-int",
157 		USB_EP_CAPS(USB_EP_CAPS_TYPE_INT, USB_EP_CAPS_DIR_IN)),
158 	EP_INFO("ep6in-bulk",
159 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_IN)),
160 	EP_INFO("ep7out-bulk",
161 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_OUT)),
162 /*
163 	EP_INFO("ep8in-iso",
164 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_IN)),
165 	EP_INFO("ep9out-iso",
166 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_OUT)),
167 */
168 	EP_INFO("ep10in-int",
169 		USB_EP_CAPS(USB_EP_CAPS_TYPE_INT, USB_EP_CAPS_DIR_IN)),
170 	EP_INFO("ep11in-bulk",
171 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_IN)),
172 	EP_INFO("ep12out-bulk",
173 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_OUT)),
174 /*
175 	EP_INFO("ep13in-iso",
176 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_IN)),
177 	EP_INFO("ep14out-iso",
178 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_OUT)),
179 */
180 	EP_INFO("ep15in-int",
181 		USB_EP_CAPS(USB_EP_CAPS_TYPE_INT, USB_EP_CAPS_DIR_IN)),
182 
183 	/* or like sa1100: two fixed function endpoints */
184 	EP_INFO("ep1out-bulk",
185 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_OUT)),
186 	EP_INFO("ep2in-bulk",
187 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_IN)),
188 
189 	/* and now some generic EPs so we have enough in multi config */
190 	EP_INFO("ep-aout",
191 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
192 	EP_INFO("ep-bin",
193 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
194 	EP_INFO("ep-cout",
195 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
196 	EP_INFO("ep-dout",
197 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
198 	EP_INFO("ep-ein",
199 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
200 	EP_INFO("ep-fout",
201 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
202 	EP_INFO("ep-gin",
203 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
204 	EP_INFO("ep-hout",
205 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
206 	EP_INFO("ep-iout",
207 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
208 	EP_INFO("ep-jin",
209 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
210 	EP_INFO("ep-kout",
211 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
212 	EP_INFO("ep-lin",
213 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
214 	EP_INFO("ep-mout",
215 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
216 
217 #undef EP_INFO
218 };
219 
220 #define DUMMY_ENDPOINTS	ARRAY_SIZE(ep_info)
221 
222 /*-------------------------------------------------------------------------*/
223 
224 #define FIFO_SIZE		64
225 
226 struct urbp {
227 	struct urb		*urb;
228 	struct list_head	urbp_list;
229 	struct sg_mapping_iter	miter;
230 	u32			miter_started;
231 };
232 
233 
234 enum dummy_rh_state {
235 	DUMMY_RH_RESET,
236 	DUMMY_RH_SUSPENDED,
237 	DUMMY_RH_RUNNING
238 };
239 
240 struct dummy_hcd {
241 	struct dummy			*dum;
242 	enum dummy_rh_state		rh_state;
243 	struct timer_list		timer;
244 	u32				port_status;
245 	u32				old_status;
246 	unsigned long			re_timeout;
247 
248 	struct usb_device		*udev;
249 	struct list_head		urbp_list;
250 	struct urbp			*next_frame_urbp;
251 
252 	u32				stream_en_ep;
253 	u8				num_stream[30 / 2];
254 
255 	unsigned			active:1;
256 	unsigned			old_active:1;
257 	unsigned			resuming:1;
258 };
259 
260 struct dummy {
261 	spinlock_t			lock;
262 
263 	/*
264 	 * DEVICE/GADGET side support
265 	 */
266 	struct dummy_ep			ep[DUMMY_ENDPOINTS];
267 	int				address;
268 	int				callback_usage;
269 	struct usb_gadget		gadget;
270 	struct usb_gadget_driver	*driver;
271 	struct dummy_request		fifo_req;
272 	u8				fifo_buf[FIFO_SIZE];
273 	u16				devstatus;
274 	unsigned			ints_enabled:1;
275 	unsigned			udc_suspended:1;
276 	unsigned			pullup:1;
277 
278 	/*
279 	 * HOST side support
280 	 */
281 	struct dummy_hcd		*hs_hcd;
282 	struct dummy_hcd		*ss_hcd;
283 };
284 
285 static inline struct dummy_hcd *hcd_to_dummy_hcd(struct usb_hcd *hcd)
286 {
287 	return (struct dummy_hcd *) (hcd->hcd_priv);
288 }
289 
290 static inline struct usb_hcd *dummy_hcd_to_hcd(struct dummy_hcd *dum)
291 {
292 	return container_of((void *) dum, struct usb_hcd, hcd_priv);
293 }
294 
295 static inline struct device *dummy_dev(struct dummy_hcd *dum)
296 {
297 	return dummy_hcd_to_hcd(dum)->self.controller;
298 }
299 
300 static inline struct device *udc_dev(struct dummy *dum)
301 {
302 	return dum->gadget.dev.parent;
303 }
304 
305 static inline struct dummy *ep_to_dummy(struct dummy_ep *ep)
306 {
307 	return container_of(ep->gadget, struct dummy, gadget);
308 }
309 
310 static inline struct dummy_hcd *gadget_to_dummy_hcd(struct usb_gadget *gadget)
311 {
312 	struct dummy *dum = container_of(gadget, struct dummy, gadget);
313 	if (dum->gadget.speed == USB_SPEED_SUPER)
314 		return dum->ss_hcd;
315 	else
316 		return dum->hs_hcd;
317 }
318 
319 static inline struct dummy *gadget_dev_to_dummy(struct device *dev)
320 {
321 	return container_of(dev, struct dummy, gadget.dev);
322 }
323 
324 /*-------------------------------------------------------------------------*/
325 
326 /* DEVICE/GADGET SIDE UTILITY ROUTINES */
327 
328 /* called with spinlock held */
329 static void nuke(struct dummy *dum, struct dummy_ep *ep)
330 {
331 	while (!list_empty(&ep->queue)) {
332 		struct dummy_request	*req;
333 
334 		req = list_entry(ep->queue.next, struct dummy_request, queue);
335 		list_del_init(&req->queue);
336 		req->req.status = -ESHUTDOWN;
337 
338 		spin_unlock(&dum->lock);
339 		usb_gadget_giveback_request(&ep->ep, &req->req);
340 		spin_lock(&dum->lock);
341 	}
342 }
343 
344 /* caller must hold lock */
345 static void stop_activity(struct dummy *dum)
346 {
347 	int i;
348 
349 	/* prevent any more requests */
350 	dum->address = 0;
351 
352 	/* The timer is left running so that outstanding URBs can fail */
353 
354 	/* nuke any pending requests first, so driver i/o is quiesced */
355 	for (i = 0; i < DUMMY_ENDPOINTS; ++i)
356 		nuke(dum, &dum->ep[i]);
357 
358 	/* driver now does any non-usb quiescing necessary */
359 }
360 
361 /**
362  * set_link_state_by_speed() - Sets the current state of the link according to
363  *	the hcd speed
364  * @dum_hcd: pointer to the dummy_hcd structure to update the link state for
365  *
366  * This function updates the port_status according to the link state and the
367  * speed of the hcd.
368  */
369 static void set_link_state_by_speed(struct dummy_hcd *dum_hcd)
370 {
371 	struct dummy *dum = dum_hcd->dum;
372 
373 	if (dummy_hcd_to_hcd(dum_hcd)->speed == HCD_USB3) {
374 		if ((dum_hcd->port_status & USB_SS_PORT_STAT_POWER) == 0) {
375 			dum_hcd->port_status = 0;
376 		} else if (!dum->pullup || dum->udc_suspended) {
377 			/* UDC suspend must cause a disconnect */
378 			dum_hcd->port_status &= ~(USB_PORT_STAT_CONNECTION |
379 						USB_PORT_STAT_ENABLE);
380 			if ((dum_hcd->old_status &
381 			     USB_PORT_STAT_CONNECTION) != 0)
382 				dum_hcd->port_status |=
383 					(USB_PORT_STAT_C_CONNECTION << 16);
384 		} else {
385 			/* device is connected and not suspended */
386 			dum_hcd->port_status |= (USB_PORT_STAT_CONNECTION |
387 						 USB_PORT_STAT_SPEED_5GBPS) ;
388 			if ((dum_hcd->old_status &
389 			     USB_PORT_STAT_CONNECTION) == 0)
390 				dum_hcd->port_status |=
391 					(USB_PORT_STAT_C_CONNECTION << 16);
392 			if ((dum_hcd->port_status & USB_PORT_STAT_ENABLE) &&
393 			    (dum_hcd->port_status &
394 			     USB_PORT_STAT_LINK_STATE) == USB_SS_PORT_LS_U0 &&
395 			    dum_hcd->rh_state != DUMMY_RH_SUSPENDED)
396 				dum_hcd->active = 1;
397 		}
398 	} else {
399 		if ((dum_hcd->port_status & USB_PORT_STAT_POWER) == 0) {
400 			dum_hcd->port_status = 0;
401 		} else if (!dum->pullup || dum->udc_suspended) {
402 			/* UDC suspend must cause a disconnect */
403 			dum_hcd->port_status &= ~(USB_PORT_STAT_CONNECTION |
404 						USB_PORT_STAT_ENABLE |
405 						USB_PORT_STAT_LOW_SPEED |
406 						USB_PORT_STAT_HIGH_SPEED |
407 						USB_PORT_STAT_SUSPEND);
408 			if ((dum_hcd->old_status &
409 			     USB_PORT_STAT_CONNECTION) != 0)
410 				dum_hcd->port_status |=
411 					(USB_PORT_STAT_C_CONNECTION << 16);
412 		} else {
413 			dum_hcd->port_status |= USB_PORT_STAT_CONNECTION;
414 			if ((dum_hcd->old_status &
415 			     USB_PORT_STAT_CONNECTION) == 0)
416 				dum_hcd->port_status |=
417 					(USB_PORT_STAT_C_CONNECTION << 16);
418 			if ((dum_hcd->port_status & USB_PORT_STAT_ENABLE) == 0)
419 				dum_hcd->port_status &= ~USB_PORT_STAT_SUSPEND;
420 			else if ((dum_hcd->port_status &
421 				  USB_PORT_STAT_SUSPEND) == 0 &&
422 					dum_hcd->rh_state != DUMMY_RH_SUSPENDED)
423 				dum_hcd->active = 1;
424 		}
425 	}
426 }
427 
428 /* caller must hold lock */
429 static void set_link_state(struct dummy_hcd *dum_hcd)
430 	__must_hold(&dum->lock)
431 {
432 	struct dummy *dum = dum_hcd->dum;
433 	unsigned int power_bit;
434 
435 	dum_hcd->active = 0;
436 	if (dum->pullup)
437 		if ((dummy_hcd_to_hcd(dum_hcd)->speed == HCD_USB3 &&
438 		     dum->gadget.speed != USB_SPEED_SUPER) ||
439 		    (dummy_hcd_to_hcd(dum_hcd)->speed != HCD_USB3 &&
440 		     dum->gadget.speed == USB_SPEED_SUPER))
441 			return;
442 
443 	set_link_state_by_speed(dum_hcd);
444 	power_bit = (dummy_hcd_to_hcd(dum_hcd)->speed == HCD_USB3 ?
445 			USB_SS_PORT_STAT_POWER : USB_PORT_STAT_POWER);
446 
447 	if ((dum_hcd->port_status & USB_PORT_STAT_ENABLE) == 0 ||
448 	     dum_hcd->active)
449 		dum_hcd->resuming = 0;
450 
451 	/* Currently !connected or in reset */
452 	if ((dum_hcd->port_status & power_bit) == 0 ||
453 			(dum_hcd->port_status & USB_PORT_STAT_RESET) != 0) {
454 		unsigned int disconnect = power_bit &
455 				dum_hcd->old_status & (~dum_hcd->port_status);
456 		unsigned int reset = USB_PORT_STAT_RESET &
457 				(~dum_hcd->old_status) & dum_hcd->port_status;
458 
459 		/* Report reset and disconnect events to the driver */
460 		if (dum->ints_enabled && (disconnect || reset)) {
461 			stop_activity(dum);
462 			++dum->callback_usage;
463 			spin_unlock(&dum->lock);
464 			if (reset)
465 				usb_gadget_udc_reset(&dum->gadget, dum->driver);
466 			else
467 				dum->driver->disconnect(&dum->gadget);
468 			spin_lock(&dum->lock);
469 			--dum->callback_usage;
470 		}
471 	} else if (dum_hcd->active != dum_hcd->old_active &&
472 			dum->ints_enabled) {
473 		++dum->callback_usage;
474 		spin_unlock(&dum->lock);
475 		if (dum_hcd->old_active && dum->driver->suspend)
476 			dum->driver->suspend(&dum->gadget);
477 		else if (!dum_hcd->old_active &&  dum->driver->resume)
478 			dum->driver->resume(&dum->gadget);
479 		spin_lock(&dum->lock);
480 		--dum->callback_usage;
481 	}
482 
483 	dum_hcd->old_status = dum_hcd->port_status;
484 	dum_hcd->old_active = dum_hcd->active;
485 }
486 
487 /*-------------------------------------------------------------------------*/
488 
489 /* DEVICE/GADGET SIDE DRIVER
490  *
491  * This only tracks gadget state.  All the work is done when the host
492  * side tries some (emulated) i/o operation.  Real device controller
493  * drivers would do real i/o using dma, fifos, irqs, timers, etc.
494  */
495 
496 #define is_enabled(dum) \
497 	(dum->port_status & USB_PORT_STAT_ENABLE)
498 
499 static int dummy_enable(struct usb_ep *_ep,
500 		const struct usb_endpoint_descriptor *desc)
501 {
502 	struct dummy		*dum;
503 	struct dummy_hcd	*dum_hcd;
504 	struct dummy_ep		*ep;
505 	unsigned		max;
506 	int			retval;
507 
508 	ep = usb_ep_to_dummy_ep(_ep);
509 	if (!_ep || !desc || ep->desc || _ep->name == ep0name
510 			|| desc->bDescriptorType != USB_DT_ENDPOINT)
511 		return -EINVAL;
512 	dum = ep_to_dummy(ep);
513 	if (!dum->driver)
514 		return -ESHUTDOWN;
515 
516 	dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
517 	if (!is_enabled(dum_hcd))
518 		return -ESHUTDOWN;
519 
520 	/*
521 	 * For HS/FS devices only bits 0..10 of the wMaxPacketSize represent the
522 	 * maximum packet size.
523 	 * For SS devices the wMaxPacketSize is limited by 1024.
524 	 */
525 	max = usb_endpoint_maxp(desc);
526 
527 	/* drivers must not request bad settings, since lower levels
528 	 * (hardware or its drivers) may not check.  some endpoints
529 	 * can't do iso, many have maxpacket limitations, etc.
530 	 *
531 	 * since this "hardware" driver is here to help debugging, we
532 	 * have some extra sanity checks.  (there could be more though,
533 	 * especially for "ep9out" style fixed function ones.)
534 	 */
535 	retval = -EINVAL;
536 	switch (usb_endpoint_type(desc)) {
537 	case USB_ENDPOINT_XFER_BULK:
538 		if (strstr(ep->ep.name, "-iso")
539 				|| strstr(ep->ep.name, "-int")) {
540 			goto done;
541 		}
542 		switch (dum->gadget.speed) {
543 		case USB_SPEED_SUPER:
544 			if (max == 1024)
545 				break;
546 			goto done;
547 		case USB_SPEED_HIGH:
548 			if (max == 512)
549 				break;
550 			goto done;
551 		case USB_SPEED_FULL:
552 			if (max == 8 || max == 16 || max == 32 || max == 64)
553 				/* we'll fake any legal size */
554 				break;
555 			/* save a return statement */
556 		default:
557 			goto done;
558 		}
559 		break;
560 	case USB_ENDPOINT_XFER_INT:
561 		if (strstr(ep->ep.name, "-iso")) /* bulk is ok */
562 			goto done;
563 		/* real hardware might not handle all packet sizes */
564 		switch (dum->gadget.speed) {
565 		case USB_SPEED_SUPER:
566 		case USB_SPEED_HIGH:
567 			if (max <= 1024)
568 				break;
569 			/* save a return statement */
570 			fallthrough;
571 		case USB_SPEED_FULL:
572 			if (max <= 64)
573 				break;
574 			/* save a return statement */
575 			fallthrough;
576 		default:
577 			if (max <= 8)
578 				break;
579 			goto done;
580 		}
581 		break;
582 	case USB_ENDPOINT_XFER_ISOC:
583 		if (strstr(ep->ep.name, "-bulk")
584 				|| strstr(ep->ep.name, "-int"))
585 			goto done;
586 		/* real hardware might not handle all packet sizes */
587 		switch (dum->gadget.speed) {
588 		case USB_SPEED_SUPER:
589 		case USB_SPEED_HIGH:
590 			if (max <= 1024)
591 				break;
592 			/* save a return statement */
593 			fallthrough;
594 		case USB_SPEED_FULL:
595 			if (max <= 1023)
596 				break;
597 			/* save a return statement */
598 		default:
599 			goto done;
600 		}
601 		break;
602 	default:
603 		/* few chips support control except on ep0 */
604 		goto done;
605 	}
606 
607 	_ep->maxpacket = max;
608 	if (usb_ss_max_streams(_ep->comp_desc)) {
609 		if (!usb_endpoint_xfer_bulk(desc)) {
610 			dev_err(udc_dev(dum), "Can't enable stream support on "
611 					"non-bulk ep %s\n", _ep->name);
612 			return -EINVAL;
613 		}
614 		ep->stream_en = 1;
615 	}
616 	ep->desc = desc;
617 
618 	dev_dbg(udc_dev(dum), "enabled %s (ep%d%s-%s) maxpacket %d stream %s\n",
619 		_ep->name,
620 		desc->bEndpointAddress & 0x0f,
621 		(desc->bEndpointAddress & USB_DIR_IN) ? "in" : "out",
622 		usb_ep_type_string(usb_endpoint_type(desc)),
623 		max, ep->stream_en ? "enabled" : "disabled");
624 
625 	/* at this point real hardware should be NAKing transfers
626 	 * to that endpoint, until a buffer is queued to it.
627 	 */
628 	ep->halted = ep->wedged = 0;
629 	retval = 0;
630 done:
631 	return retval;
632 }
633 
634 static int dummy_disable(struct usb_ep *_ep)
635 {
636 	struct dummy_ep		*ep;
637 	struct dummy		*dum;
638 	unsigned long		flags;
639 
640 	ep = usb_ep_to_dummy_ep(_ep);
641 	if (!_ep || !ep->desc || _ep->name == ep0name)
642 		return -EINVAL;
643 	dum = ep_to_dummy(ep);
644 
645 	spin_lock_irqsave(&dum->lock, flags);
646 	ep->desc = NULL;
647 	ep->stream_en = 0;
648 	nuke(dum, ep);
649 	spin_unlock_irqrestore(&dum->lock, flags);
650 
651 	dev_dbg(udc_dev(dum), "disabled %s\n", _ep->name);
652 	return 0;
653 }
654 
655 static struct usb_request *dummy_alloc_request(struct usb_ep *_ep,
656 		gfp_t mem_flags)
657 {
658 	struct dummy_request	*req;
659 
660 	if (!_ep)
661 		return NULL;
662 
663 	req = kzalloc(sizeof(*req), mem_flags);
664 	if (!req)
665 		return NULL;
666 	INIT_LIST_HEAD(&req->queue);
667 	return &req->req;
668 }
669 
670 static void dummy_free_request(struct usb_ep *_ep, struct usb_request *_req)
671 {
672 	struct dummy_request	*req;
673 
674 	if (!_ep || !_req) {
675 		WARN_ON(1);
676 		return;
677 	}
678 
679 	req = usb_request_to_dummy_request(_req);
680 	WARN_ON(!list_empty(&req->queue));
681 	kfree(req);
682 }
683 
684 static void fifo_complete(struct usb_ep *ep, struct usb_request *req)
685 {
686 }
687 
688 static int dummy_queue(struct usb_ep *_ep, struct usb_request *_req,
689 		gfp_t mem_flags)
690 {
691 	struct dummy_ep		*ep;
692 	struct dummy_request	*req;
693 	struct dummy		*dum;
694 	struct dummy_hcd	*dum_hcd;
695 	unsigned long		flags;
696 
697 	req = usb_request_to_dummy_request(_req);
698 	if (!_req || !list_empty(&req->queue) || !_req->complete)
699 		return -EINVAL;
700 
701 	ep = usb_ep_to_dummy_ep(_ep);
702 	if (!_ep || (!ep->desc && _ep->name != ep0name))
703 		return -EINVAL;
704 
705 	dum = ep_to_dummy(ep);
706 	dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
707 	if (!dum->driver || !is_enabled(dum_hcd))
708 		return -ESHUTDOWN;
709 
710 #if 0
711 	dev_dbg(udc_dev(dum), "ep %p queue req %p to %s, len %d buf %p\n",
712 			ep, _req, _ep->name, _req->length, _req->buf);
713 #endif
714 	_req->status = -EINPROGRESS;
715 	_req->actual = 0;
716 	spin_lock_irqsave(&dum->lock, flags);
717 
718 	/* implement an emulated single-request FIFO */
719 	if (ep->desc && (ep->desc->bEndpointAddress & USB_DIR_IN) &&
720 			list_empty(&dum->fifo_req.queue) &&
721 			list_empty(&ep->queue) &&
722 			_req->length <= FIFO_SIZE) {
723 		req = &dum->fifo_req;
724 		req->req = *_req;
725 		req->req.buf = dum->fifo_buf;
726 		memcpy(dum->fifo_buf, _req->buf, _req->length);
727 		req->req.context = dum;
728 		req->req.complete = fifo_complete;
729 
730 		list_add_tail(&req->queue, &ep->queue);
731 		spin_unlock(&dum->lock);
732 		_req->actual = _req->length;
733 		_req->status = 0;
734 		usb_gadget_giveback_request(_ep, _req);
735 		spin_lock(&dum->lock);
736 	}  else
737 		list_add_tail(&req->queue, &ep->queue);
738 	spin_unlock_irqrestore(&dum->lock, flags);
739 
740 	/* real hardware would likely enable transfers here, in case
741 	 * it'd been left NAKing.
742 	 */
743 	return 0;
744 }
745 
746 static int dummy_dequeue(struct usb_ep *_ep, struct usb_request *_req)
747 {
748 	struct dummy_ep		*ep;
749 	struct dummy		*dum;
750 	int			retval = -EINVAL;
751 	unsigned long		flags;
752 	struct dummy_request	*req = NULL;
753 
754 	if (!_ep || !_req)
755 		return retval;
756 	ep = usb_ep_to_dummy_ep(_ep);
757 	dum = ep_to_dummy(ep);
758 
759 	if (!dum->driver)
760 		return -ESHUTDOWN;
761 
762 	local_irq_save(flags);
763 	spin_lock(&dum->lock);
764 	list_for_each_entry(req, &ep->queue, queue) {
765 		if (&req->req == _req) {
766 			list_del_init(&req->queue);
767 			_req->status = -ECONNRESET;
768 			retval = 0;
769 			break;
770 		}
771 	}
772 	spin_unlock(&dum->lock);
773 
774 	if (retval == 0) {
775 		dev_dbg(udc_dev(dum),
776 				"dequeued req %p from %s, len %d buf %p\n",
777 				req, _ep->name, _req->length, _req->buf);
778 		usb_gadget_giveback_request(_ep, _req);
779 	}
780 	local_irq_restore(flags);
781 	return retval;
782 }
783 
784 static int
785 dummy_set_halt_and_wedge(struct usb_ep *_ep, int value, int wedged)
786 {
787 	struct dummy_ep		*ep;
788 	struct dummy		*dum;
789 
790 	if (!_ep)
791 		return -EINVAL;
792 	ep = usb_ep_to_dummy_ep(_ep);
793 	dum = ep_to_dummy(ep);
794 	if (!dum->driver)
795 		return -ESHUTDOWN;
796 	if (!value)
797 		ep->halted = ep->wedged = 0;
798 	else if (ep->desc && (ep->desc->bEndpointAddress & USB_DIR_IN) &&
799 			!list_empty(&ep->queue))
800 		return -EAGAIN;
801 	else {
802 		ep->halted = 1;
803 		if (wedged)
804 			ep->wedged = 1;
805 	}
806 	/* FIXME clear emulated data toggle too */
807 	return 0;
808 }
809 
810 static int
811 dummy_set_halt(struct usb_ep *_ep, int value)
812 {
813 	return dummy_set_halt_and_wedge(_ep, value, 0);
814 }
815 
816 static int dummy_set_wedge(struct usb_ep *_ep)
817 {
818 	if (!_ep || _ep->name == ep0name)
819 		return -EINVAL;
820 	return dummy_set_halt_and_wedge(_ep, 1, 1);
821 }
822 
823 static const struct usb_ep_ops dummy_ep_ops = {
824 	.enable		= dummy_enable,
825 	.disable	= dummy_disable,
826 
827 	.alloc_request	= dummy_alloc_request,
828 	.free_request	= dummy_free_request,
829 
830 	.queue		= dummy_queue,
831 	.dequeue	= dummy_dequeue,
832 
833 	.set_halt	= dummy_set_halt,
834 	.set_wedge	= dummy_set_wedge,
835 };
836 
837 /*-------------------------------------------------------------------------*/
838 
839 /* there are both host and device side versions of this call ... */
840 static int dummy_g_get_frame(struct usb_gadget *_gadget)
841 {
842 	struct timespec64 ts64;
843 
844 	ktime_get_ts64(&ts64);
845 	return ts64.tv_nsec / NSEC_PER_MSEC;
846 }
847 
848 static int dummy_wakeup(struct usb_gadget *_gadget)
849 {
850 	struct dummy_hcd *dum_hcd;
851 
852 	dum_hcd = gadget_to_dummy_hcd(_gadget);
853 	if (!(dum_hcd->dum->devstatus & ((1 << USB_DEVICE_B_HNP_ENABLE)
854 				| (1 << USB_DEVICE_REMOTE_WAKEUP))))
855 		return -EINVAL;
856 	if ((dum_hcd->port_status & USB_PORT_STAT_CONNECTION) == 0)
857 		return -ENOLINK;
858 	if ((dum_hcd->port_status & USB_PORT_STAT_SUSPEND) == 0 &&
859 			 dum_hcd->rh_state != DUMMY_RH_SUSPENDED)
860 		return -EIO;
861 
862 	/* FIXME: What if the root hub is suspended but the port isn't? */
863 
864 	/* hub notices our request, issues downstream resume, etc */
865 	dum_hcd->resuming = 1;
866 	dum_hcd->re_timeout = jiffies + msecs_to_jiffies(20);
867 	mod_timer(&dummy_hcd_to_hcd(dum_hcd)->rh_timer, dum_hcd->re_timeout);
868 	return 0;
869 }
870 
871 static int dummy_set_selfpowered(struct usb_gadget *_gadget, int value)
872 {
873 	struct dummy	*dum;
874 
875 	_gadget->is_selfpowered = (value != 0);
876 	dum = gadget_to_dummy_hcd(_gadget)->dum;
877 	if (value)
878 		dum->devstatus |= (1 << USB_DEVICE_SELF_POWERED);
879 	else
880 		dum->devstatus &= ~(1 << USB_DEVICE_SELF_POWERED);
881 	return 0;
882 }
883 
884 static void dummy_udc_update_ep0(struct dummy *dum)
885 {
886 	if (dum->gadget.speed == USB_SPEED_SUPER)
887 		dum->ep[0].ep.maxpacket = 9;
888 	else
889 		dum->ep[0].ep.maxpacket = 64;
890 }
891 
892 static int dummy_pullup(struct usb_gadget *_gadget, int value)
893 {
894 	struct dummy_hcd *dum_hcd;
895 	struct dummy	*dum;
896 	unsigned long	flags;
897 
898 	dum = gadget_dev_to_dummy(&_gadget->dev);
899 	dum_hcd = gadget_to_dummy_hcd(_gadget);
900 
901 	spin_lock_irqsave(&dum->lock, flags);
902 	dum->pullup = (value != 0);
903 	set_link_state(dum_hcd);
904 	spin_unlock_irqrestore(&dum->lock, flags);
905 
906 	usb_hcd_poll_rh_status(dummy_hcd_to_hcd(dum_hcd));
907 	return 0;
908 }
909 
910 static void dummy_udc_set_speed(struct usb_gadget *_gadget,
911 		enum usb_device_speed speed)
912 {
913 	struct dummy	*dum;
914 
915 	dum = gadget_dev_to_dummy(&_gadget->dev);
916 	dum->gadget.speed = speed;
917 	dummy_udc_update_ep0(dum);
918 }
919 
920 static int dummy_udc_start(struct usb_gadget *g,
921 		struct usb_gadget_driver *driver);
922 static int dummy_udc_stop(struct usb_gadget *g);
923 
924 static const struct usb_gadget_ops dummy_ops = {
925 	.get_frame	= dummy_g_get_frame,
926 	.wakeup		= dummy_wakeup,
927 	.set_selfpowered = dummy_set_selfpowered,
928 	.pullup		= dummy_pullup,
929 	.udc_start	= dummy_udc_start,
930 	.udc_stop	= dummy_udc_stop,
931 	.udc_set_speed	= dummy_udc_set_speed,
932 };
933 
934 /*-------------------------------------------------------------------------*/
935 
936 /* "function" sysfs attribute */
937 static ssize_t function_show(struct device *dev, struct device_attribute *attr,
938 		char *buf)
939 {
940 	struct dummy	*dum = gadget_dev_to_dummy(dev);
941 
942 	if (!dum->driver || !dum->driver->function)
943 		return 0;
944 	return scnprintf(buf, PAGE_SIZE, "%s\n", dum->driver->function);
945 }
946 static DEVICE_ATTR_RO(function);
947 
948 /*-------------------------------------------------------------------------*/
949 
950 /*
951  * Driver registration/unregistration.
952  *
953  * This is basically hardware-specific; there's usually only one real USB
954  * device (not host) controller since that's how USB devices are intended
955  * to work.  So most implementations of these api calls will rely on the
956  * fact that only one driver will ever bind to the hardware.  But curious
957  * hardware can be built with discrete components, so the gadget API doesn't
958  * require that assumption.
959  *
960  * For this emulator, it might be convenient to create a usb device
961  * for each driver that registers:  just add to a big root hub.
962  */
963 
964 static int dummy_udc_start(struct usb_gadget *g,
965 		struct usb_gadget_driver *driver)
966 {
967 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(g);
968 	struct dummy		*dum = dum_hcd->dum;
969 
970 	switch (g->speed) {
971 	/* All the speeds we support */
972 	case USB_SPEED_LOW:
973 	case USB_SPEED_FULL:
974 	case USB_SPEED_HIGH:
975 	case USB_SPEED_SUPER:
976 		break;
977 	default:
978 		dev_err(dummy_dev(dum_hcd), "Unsupported driver max speed %d\n",
979 				driver->max_speed);
980 		return -EINVAL;
981 	}
982 
983 	/*
984 	 * DEVICE side init ... the layer above hardware, which
985 	 * can't enumerate without help from the driver we're binding.
986 	 */
987 
988 	spin_lock_irq(&dum->lock);
989 	dum->devstatus = 0;
990 	dum->driver = driver;
991 	dum->ints_enabled = 1;
992 	spin_unlock_irq(&dum->lock);
993 
994 	return 0;
995 }
996 
997 static int dummy_udc_stop(struct usb_gadget *g)
998 {
999 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(g);
1000 	struct dummy		*dum = dum_hcd->dum;
1001 
1002 	spin_lock_irq(&dum->lock);
1003 	dum->ints_enabled = 0;
1004 	stop_activity(dum);
1005 
1006 	/* emulate synchronize_irq(): wait for callbacks to finish */
1007 	while (dum->callback_usage > 0) {
1008 		spin_unlock_irq(&dum->lock);
1009 		usleep_range(1000, 2000);
1010 		spin_lock_irq(&dum->lock);
1011 	}
1012 
1013 	dum->driver = NULL;
1014 	spin_unlock_irq(&dum->lock);
1015 
1016 	return 0;
1017 }
1018 
1019 #undef is_enabled
1020 
1021 /* The gadget structure is stored inside the hcd structure and will be
1022  * released along with it. */
1023 static void init_dummy_udc_hw(struct dummy *dum)
1024 {
1025 	int i;
1026 
1027 	INIT_LIST_HEAD(&dum->gadget.ep_list);
1028 	for (i = 0; i < DUMMY_ENDPOINTS; i++) {
1029 		struct dummy_ep	*ep = &dum->ep[i];
1030 
1031 		if (!ep_info[i].name)
1032 			break;
1033 		ep->ep.name = ep_info[i].name;
1034 		ep->ep.caps = ep_info[i].caps;
1035 		ep->ep.ops = &dummy_ep_ops;
1036 		list_add_tail(&ep->ep.ep_list, &dum->gadget.ep_list);
1037 		ep->halted = ep->wedged = ep->already_seen =
1038 				ep->setup_stage = 0;
1039 		usb_ep_set_maxpacket_limit(&ep->ep, ~0);
1040 		ep->ep.max_streams = 16;
1041 		ep->last_io = jiffies;
1042 		ep->gadget = &dum->gadget;
1043 		ep->desc = NULL;
1044 		INIT_LIST_HEAD(&ep->queue);
1045 	}
1046 
1047 	dum->gadget.ep0 = &dum->ep[0].ep;
1048 	list_del_init(&dum->ep[0].ep.ep_list);
1049 	INIT_LIST_HEAD(&dum->fifo_req.queue);
1050 
1051 #ifdef CONFIG_USB_OTG
1052 	dum->gadget.is_otg = 1;
1053 #endif
1054 }
1055 
1056 static int dummy_udc_probe(struct platform_device *pdev)
1057 {
1058 	struct dummy	*dum;
1059 	int		rc;
1060 
1061 	dum = *((void **)dev_get_platdata(&pdev->dev));
1062 	/* Clear usb_gadget region for new registration to udc-core */
1063 	memzero_explicit(&dum->gadget, sizeof(struct usb_gadget));
1064 	dum->gadget.name = gadget_name;
1065 	dum->gadget.ops = &dummy_ops;
1066 	if (mod_data.is_super_speed)
1067 		dum->gadget.max_speed = USB_SPEED_SUPER;
1068 	else if (mod_data.is_high_speed)
1069 		dum->gadget.max_speed = USB_SPEED_HIGH;
1070 	else
1071 		dum->gadget.max_speed = USB_SPEED_FULL;
1072 
1073 	dum->gadget.dev.parent = &pdev->dev;
1074 	init_dummy_udc_hw(dum);
1075 
1076 	rc = usb_add_gadget_udc(&pdev->dev, &dum->gadget);
1077 	if (rc < 0)
1078 		goto err_udc;
1079 
1080 	rc = device_create_file(&dum->gadget.dev, &dev_attr_function);
1081 	if (rc < 0)
1082 		goto err_dev;
1083 	platform_set_drvdata(pdev, dum);
1084 	return rc;
1085 
1086 err_dev:
1087 	usb_del_gadget_udc(&dum->gadget);
1088 err_udc:
1089 	return rc;
1090 }
1091 
1092 static int dummy_udc_remove(struct platform_device *pdev)
1093 {
1094 	struct dummy	*dum = platform_get_drvdata(pdev);
1095 
1096 	device_remove_file(&dum->gadget.dev, &dev_attr_function);
1097 	usb_del_gadget_udc(&dum->gadget);
1098 	return 0;
1099 }
1100 
1101 static void dummy_udc_pm(struct dummy *dum, struct dummy_hcd *dum_hcd,
1102 		int suspend)
1103 {
1104 	spin_lock_irq(&dum->lock);
1105 	dum->udc_suspended = suspend;
1106 	set_link_state(dum_hcd);
1107 	spin_unlock_irq(&dum->lock);
1108 }
1109 
1110 static int dummy_udc_suspend(struct platform_device *pdev, pm_message_t state)
1111 {
1112 	struct dummy		*dum = platform_get_drvdata(pdev);
1113 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
1114 
1115 	dev_dbg(&pdev->dev, "%s\n", __func__);
1116 	dummy_udc_pm(dum, dum_hcd, 1);
1117 	usb_hcd_poll_rh_status(dummy_hcd_to_hcd(dum_hcd));
1118 	return 0;
1119 }
1120 
1121 static int dummy_udc_resume(struct platform_device *pdev)
1122 {
1123 	struct dummy		*dum = platform_get_drvdata(pdev);
1124 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
1125 
1126 	dev_dbg(&pdev->dev, "%s\n", __func__);
1127 	dummy_udc_pm(dum, dum_hcd, 0);
1128 	usb_hcd_poll_rh_status(dummy_hcd_to_hcd(dum_hcd));
1129 	return 0;
1130 }
1131 
1132 static struct platform_driver dummy_udc_driver = {
1133 	.probe		= dummy_udc_probe,
1134 	.remove		= dummy_udc_remove,
1135 	.suspend	= dummy_udc_suspend,
1136 	.resume		= dummy_udc_resume,
1137 	.driver		= {
1138 		.name	= gadget_name,
1139 	},
1140 };
1141 
1142 /*-------------------------------------------------------------------------*/
1143 
1144 static unsigned int dummy_get_ep_idx(const struct usb_endpoint_descriptor *desc)
1145 {
1146 	unsigned int index;
1147 
1148 	index = usb_endpoint_num(desc) << 1;
1149 	if (usb_endpoint_dir_in(desc))
1150 		index |= 1;
1151 	return index;
1152 }
1153 
1154 /* HOST SIDE DRIVER
1155  *
1156  * this uses the hcd framework to hook up to host side drivers.
1157  * its root hub will only have one device, otherwise it acts like
1158  * a normal host controller.
1159  *
1160  * when urbs are queued, they're just stuck on a list that we
1161  * scan in a timer callback.  that callback connects writes from
1162  * the host with reads from the device, and so on, based on the
1163  * usb 2.0 rules.
1164  */
1165 
1166 static int dummy_ep_stream_en(struct dummy_hcd *dum_hcd, struct urb *urb)
1167 {
1168 	const struct usb_endpoint_descriptor *desc = &urb->ep->desc;
1169 	u32 index;
1170 
1171 	if (!usb_endpoint_xfer_bulk(desc))
1172 		return 0;
1173 
1174 	index = dummy_get_ep_idx(desc);
1175 	return (1 << index) & dum_hcd->stream_en_ep;
1176 }
1177 
1178 /*
1179  * The max stream number is saved as a nibble so for the 30 possible endpoints
1180  * we only 15 bytes of memory. Therefore we are limited to max 16 streams (0
1181  * means we use only 1 stream). The maximum according to the spec is 16bit so
1182  * if the 16 stream limit is about to go, the array size should be incremented
1183  * to 30 elements of type u16.
1184  */
1185 static int get_max_streams_for_pipe(struct dummy_hcd *dum_hcd,
1186 		unsigned int pipe)
1187 {
1188 	int max_streams;
1189 
1190 	max_streams = dum_hcd->num_stream[usb_pipeendpoint(pipe)];
1191 	if (usb_pipeout(pipe))
1192 		max_streams >>= 4;
1193 	else
1194 		max_streams &= 0xf;
1195 	max_streams++;
1196 	return max_streams;
1197 }
1198 
1199 static void set_max_streams_for_pipe(struct dummy_hcd *dum_hcd,
1200 		unsigned int pipe, unsigned int streams)
1201 {
1202 	int max_streams;
1203 
1204 	streams--;
1205 	max_streams = dum_hcd->num_stream[usb_pipeendpoint(pipe)];
1206 	if (usb_pipeout(pipe)) {
1207 		streams <<= 4;
1208 		max_streams &= 0xf;
1209 	} else {
1210 		max_streams &= 0xf0;
1211 	}
1212 	max_streams |= streams;
1213 	dum_hcd->num_stream[usb_pipeendpoint(pipe)] = max_streams;
1214 }
1215 
1216 static int dummy_validate_stream(struct dummy_hcd *dum_hcd, struct urb *urb)
1217 {
1218 	unsigned int max_streams;
1219 	int enabled;
1220 
1221 	enabled = dummy_ep_stream_en(dum_hcd, urb);
1222 	if (!urb->stream_id) {
1223 		if (enabled)
1224 			return -EINVAL;
1225 		return 0;
1226 	}
1227 	if (!enabled)
1228 		return -EINVAL;
1229 
1230 	max_streams = get_max_streams_for_pipe(dum_hcd,
1231 			usb_pipeendpoint(urb->pipe));
1232 	if (urb->stream_id > max_streams) {
1233 		dev_err(dummy_dev(dum_hcd), "Stream id %d is out of range.\n",
1234 				urb->stream_id);
1235 		BUG();
1236 		return -EINVAL;
1237 	}
1238 	return 0;
1239 }
1240 
1241 static int dummy_urb_enqueue(
1242 	struct usb_hcd			*hcd,
1243 	struct urb			*urb,
1244 	gfp_t				mem_flags
1245 ) {
1246 	struct dummy_hcd *dum_hcd;
1247 	struct urbp	*urbp;
1248 	unsigned long	flags;
1249 	int		rc;
1250 
1251 	urbp = kmalloc(sizeof *urbp, mem_flags);
1252 	if (!urbp)
1253 		return -ENOMEM;
1254 	urbp->urb = urb;
1255 	urbp->miter_started = 0;
1256 
1257 	dum_hcd = hcd_to_dummy_hcd(hcd);
1258 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
1259 
1260 	rc = dummy_validate_stream(dum_hcd, urb);
1261 	if (rc) {
1262 		kfree(urbp);
1263 		goto done;
1264 	}
1265 
1266 	rc = usb_hcd_link_urb_to_ep(hcd, urb);
1267 	if (rc) {
1268 		kfree(urbp);
1269 		goto done;
1270 	}
1271 
1272 	if (!dum_hcd->udev) {
1273 		dum_hcd->udev = urb->dev;
1274 		usb_get_dev(dum_hcd->udev);
1275 	} else if (unlikely(dum_hcd->udev != urb->dev))
1276 		dev_err(dummy_dev(dum_hcd), "usb_device address has changed!\n");
1277 
1278 	list_add_tail(&urbp->urbp_list, &dum_hcd->urbp_list);
1279 	urb->hcpriv = urbp;
1280 	if (!dum_hcd->next_frame_urbp)
1281 		dum_hcd->next_frame_urbp = urbp;
1282 	if (usb_pipetype(urb->pipe) == PIPE_CONTROL)
1283 		urb->error_count = 1;		/* mark as a new urb */
1284 
1285 	/* kick the scheduler, it'll do the rest */
1286 	if (!timer_pending(&dum_hcd->timer))
1287 		mod_timer(&dum_hcd->timer, jiffies + 1);
1288 
1289  done:
1290 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
1291 	return rc;
1292 }
1293 
1294 static int dummy_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
1295 {
1296 	struct dummy_hcd *dum_hcd;
1297 	unsigned long	flags;
1298 	int		rc;
1299 
1300 	/* giveback happens automatically in timer callback,
1301 	 * so make sure the callback happens */
1302 	dum_hcd = hcd_to_dummy_hcd(hcd);
1303 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
1304 
1305 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
1306 	if (!rc && dum_hcd->rh_state != DUMMY_RH_RUNNING &&
1307 			!list_empty(&dum_hcd->urbp_list))
1308 		mod_timer(&dum_hcd->timer, jiffies);
1309 
1310 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
1311 	return rc;
1312 }
1313 
1314 static int dummy_perform_transfer(struct urb *urb, struct dummy_request *req,
1315 		u32 len)
1316 {
1317 	void *ubuf, *rbuf;
1318 	struct urbp *urbp = urb->hcpriv;
1319 	int to_host;
1320 	struct sg_mapping_iter *miter = &urbp->miter;
1321 	u32 trans = 0;
1322 	u32 this_sg;
1323 	bool next_sg;
1324 
1325 	to_host = usb_urb_dir_in(urb);
1326 	rbuf = req->req.buf + req->req.actual;
1327 
1328 	if (!urb->num_sgs) {
1329 		ubuf = urb->transfer_buffer + urb->actual_length;
1330 		if (to_host)
1331 			memcpy(ubuf, rbuf, len);
1332 		else
1333 			memcpy(rbuf, ubuf, len);
1334 		return len;
1335 	}
1336 
1337 	if (!urbp->miter_started) {
1338 		u32 flags = SG_MITER_ATOMIC;
1339 
1340 		if (to_host)
1341 			flags |= SG_MITER_TO_SG;
1342 		else
1343 			flags |= SG_MITER_FROM_SG;
1344 
1345 		sg_miter_start(miter, urb->sg, urb->num_sgs, flags);
1346 		urbp->miter_started = 1;
1347 	}
1348 	next_sg = sg_miter_next(miter);
1349 	if (next_sg == false) {
1350 		WARN_ON_ONCE(1);
1351 		return -EINVAL;
1352 	}
1353 	do {
1354 		ubuf = miter->addr;
1355 		this_sg = min_t(u32, len, miter->length);
1356 		miter->consumed = this_sg;
1357 		trans += this_sg;
1358 
1359 		if (to_host)
1360 			memcpy(ubuf, rbuf, this_sg);
1361 		else
1362 			memcpy(rbuf, ubuf, this_sg);
1363 		len -= this_sg;
1364 
1365 		if (!len)
1366 			break;
1367 		next_sg = sg_miter_next(miter);
1368 		if (next_sg == false) {
1369 			WARN_ON_ONCE(1);
1370 			return -EINVAL;
1371 		}
1372 
1373 		rbuf += this_sg;
1374 	} while (1);
1375 
1376 	sg_miter_stop(miter);
1377 	return trans;
1378 }
1379 
1380 /* transfer up to a frame's worth; caller must own lock */
1381 static int transfer(struct dummy_hcd *dum_hcd, struct urb *urb,
1382 		struct dummy_ep *ep, int limit, int *status)
1383 {
1384 	struct dummy		*dum = dum_hcd->dum;
1385 	struct dummy_request	*req;
1386 	int			sent = 0;
1387 
1388 top:
1389 	/* if there's no request queued, the device is NAKing; return */
1390 	list_for_each_entry(req, &ep->queue, queue) {
1391 		unsigned	host_len, dev_len, len;
1392 		int		is_short, to_host;
1393 		int		rescan = 0;
1394 
1395 		if (dummy_ep_stream_en(dum_hcd, urb)) {
1396 			if ((urb->stream_id != req->req.stream_id))
1397 				continue;
1398 		}
1399 
1400 		/* 1..N packets of ep->ep.maxpacket each ... the last one
1401 		 * may be short (including zero length).
1402 		 *
1403 		 * writer can send a zlp explicitly (length 0) or implicitly
1404 		 * (length mod maxpacket zero, and 'zero' flag); they always
1405 		 * terminate reads.
1406 		 */
1407 		host_len = urb->transfer_buffer_length - urb->actual_length;
1408 		dev_len = req->req.length - req->req.actual;
1409 		len = min(host_len, dev_len);
1410 
1411 		/* FIXME update emulated data toggle too */
1412 
1413 		to_host = usb_urb_dir_in(urb);
1414 		if (unlikely(len == 0))
1415 			is_short = 1;
1416 		else {
1417 			/* not enough bandwidth left? */
1418 			if (limit < ep->ep.maxpacket && limit < len)
1419 				break;
1420 			len = min_t(unsigned, len, limit);
1421 			if (len == 0)
1422 				break;
1423 
1424 			/* send multiple of maxpacket first, then remainder */
1425 			if (len >= ep->ep.maxpacket) {
1426 				is_short = 0;
1427 				if (len % ep->ep.maxpacket)
1428 					rescan = 1;
1429 				len -= len % ep->ep.maxpacket;
1430 			} else {
1431 				is_short = 1;
1432 			}
1433 
1434 			len = dummy_perform_transfer(urb, req, len);
1435 
1436 			ep->last_io = jiffies;
1437 			if ((int)len < 0) {
1438 				req->req.status = len;
1439 			} else {
1440 				limit -= len;
1441 				sent += len;
1442 				urb->actual_length += len;
1443 				req->req.actual += len;
1444 			}
1445 		}
1446 
1447 		/* short packets terminate, maybe with overflow/underflow.
1448 		 * it's only really an error to write too much.
1449 		 *
1450 		 * partially filling a buffer optionally blocks queue advances
1451 		 * (so completion handlers can clean up the queue) but we don't
1452 		 * need to emulate such data-in-flight.
1453 		 */
1454 		if (is_short) {
1455 			if (host_len == dev_len) {
1456 				req->req.status = 0;
1457 				*status = 0;
1458 			} else if (to_host) {
1459 				req->req.status = 0;
1460 				if (dev_len > host_len)
1461 					*status = -EOVERFLOW;
1462 				else
1463 					*status = 0;
1464 			} else {
1465 				*status = 0;
1466 				if (host_len > dev_len)
1467 					req->req.status = -EOVERFLOW;
1468 				else
1469 					req->req.status = 0;
1470 			}
1471 
1472 		/*
1473 		 * many requests terminate without a short packet.
1474 		 * send a zlp if demanded by flags.
1475 		 */
1476 		} else {
1477 			if (req->req.length == req->req.actual) {
1478 				if (req->req.zero && to_host)
1479 					rescan = 1;
1480 				else
1481 					req->req.status = 0;
1482 			}
1483 			if (urb->transfer_buffer_length == urb->actual_length) {
1484 				if (urb->transfer_flags & URB_ZERO_PACKET &&
1485 				    !to_host)
1486 					rescan = 1;
1487 				else
1488 					*status = 0;
1489 			}
1490 		}
1491 
1492 		/* device side completion --> continuable */
1493 		if (req->req.status != -EINPROGRESS) {
1494 			list_del_init(&req->queue);
1495 
1496 			spin_unlock(&dum->lock);
1497 			usb_gadget_giveback_request(&ep->ep, &req->req);
1498 			spin_lock(&dum->lock);
1499 
1500 			/* requests might have been unlinked... */
1501 			rescan = 1;
1502 		}
1503 
1504 		/* host side completion --> terminate */
1505 		if (*status != -EINPROGRESS)
1506 			break;
1507 
1508 		/* rescan to continue with any other queued i/o */
1509 		if (rescan)
1510 			goto top;
1511 	}
1512 	return sent;
1513 }
1514 
1515 static int periodic_bytes(struct dummy *dum, struct dummy_ep *ep)
1516 {
1517 	int	limit = ep->ep.maxpacket;
1518 
1519 	if (dum->gadget.speed == USB_SPEED_HIGH) {
1520 		int	tmp;
1521 
1522 		/* high bandwidth mode */
1523 		tmp = usb_endpoint_maxp_mult(ep->desc);
1524 		tmp *= 8 /* applies to entire frame */;
1525 		limit += limit * tmp;
1526 	}
1527 	if (dum->gadget.speed == USB_SPEED_SUPER) {
1528 		switch (usb_endpoint_type(ep->desc)) {
1529 		case USB_ENDPOINT_XFER_ISOC:
1530 			/* Sec. 4.4.8.2 USB3.0 Spec */
1531 			limit = 3 * 16 * 1024 * 8;
1532 			break;
1533 		case USB_ENDPOINT_XFER_INT:
1534 			/* Sec. 4.4.7.2 USB3.0 Spec */
1535 			limit = 3 * 1024 * 8;
1536 			break;
1537 		case USB_ENDPOINT_XFER_BULK:
1538 		default:
1539 			break;
1540 		}
1541 	}
1542 	return limit;
1543 }
1544 
1545 #define is_active(dum_hcd)	((dum_hcd->port_status & \
1546 		(USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE | \
1547 			USB_PORT_STAT_SUSPEND)) \
1548 		== (USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE))
1549 
1550 static struct dummy_ep *find_endpoint(struct dummy *dum, u8 address)
1551 {
1552 	int		i;
1553 
1554 	if (!is_active((dum->gadget.speed == USB_SPEED_SUPER ?
1555 			dum->ss_hcd : dum->hs_hcd)))
1556 		return NULL;
1557 	if (!dum->ints_enabled)
1558 		return NULL;
1559 	if ((address & ~USB_DIR_IN) == 0)
1560 		return &dum->ep[0];
1561 	for (i = 1; i < DUMMY_ENDPOINTS; i++) {
1562 		struct dummy_ep	*ep = &dum->ep[i];
1563 
1564 		if (!ep->desc)
1565 			continue;
1566 		if (ep->desc->bEndpointAddress == address)
1567 			return ep;
1568 	}
1569 	return NULL;
1570 }
1571 
1572 #undef is_active
1573 
1574 #define Dev_Request	(USB_TYPE_STANDARD | USB_RECIP_DEVICE)
1575 #define Dev_InRequest	(Dev_Request | USB_DIR_IN)
1576 #define Intf_Request	(USB_TYPE_STANDARD | USB_RECIP_INTERFACE)
1577 #define Intf_InRequest	(Intf_Request | USB_DIR_IN)
1578 #define Ep_Request	(USB_TYPE_STANDARD | USB_RECIP_ENDPOINT)
1579 #define Ep_InRequest	(Ep_Request | USB_DIR_IN)
1580 
1581 
1582 /**
1583  * handle_control_request() - handles all control transfers
1584  * @dum_hcd: pointer to dummy (the_controller)
1585  * @urb: the urb request to handle
1586  * @setup: pointer to the setup data for a USB device control
1587  *	 request
1588  * @status: pointer to request handling status
1589  *
1590  * Return 0 - if the request was handled
1591  *	  1 - if the request wasn't handles
1592  *	  error code on error
1593  */
1594 static int handle_control_request(struct dummy_hcd *dum_hcd, struct urb *urb,
1595 				  struct usb_ctrlrequest *setup,
1596 				  int *status)
1597 {
1598 	struct dummy_ep		*ep2;
1599 	struct dummy		*dum = dum_hcd->dum;
1600 	int			ret_val = 1;
1601 	unsigned	w_index;
1602 	unsigned	w_value;
1603 
1604 	w_index = le16_to_cpu(setup->wIndex);
1605 	w_value = le16_to_cpu(setup->wValue);
1606 	switch (setup->bRequest) {
1607 	case USB_REQ_SET_ADDRESS:
1608 		if (setup->bRequestType != Dev_Request)
1609 			break;
1610 		dum->address = w_value;
1611 		*status = 0;
1612 		dev_dbg(udc_dev(dum), "set_address = %d\n",
1613 				w_value);
1614 		ret_val = 0;
1615 		break;
1616 	case USB_REQ_SET_FEATURE:
1617 		if (setup->bRequestType == Dev_Request) {
1618 			ret_val = 0;
1619 			switch (w_value) {
1620 			case USB_DEVICE_REMOTE_WAKEUP:
1621 				break;
1622 			case USB_DEVICE_B_HNP_ENABLE:
1623 				dum->gadget.b_hnp_enable = 1;
1624 				break;
1625 			case USB_DEVICE_A_HNP_SUPPORT:
1626 				dum->gadget.a_hnp_support = 1;
1627 				break;
1628 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1629 				dum->gadget.a_alt_hnp_support = 1;
1630 				break;
1631 			case USB_DEVICE_U1_ENABLE:
1632 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1633 				    HCD_USB3)
1634 					w_value = USB_DEV_STAT_U1_ENABLED;
1635 				else
1636 					ret_val = -EOPNOTSUPP;
1637 				break;
1638 			case USB_DEVICE_U2_ENABLE:
1639 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1640 				    HCD_USB3)
1641 					w_value = USB_DEV_STAT_U2_ENABLED;
1642 				else
1643 					ret_val = -EOPNOTSUPP;
1644 				break;
1645 			case USB_DEVICE_LTM_ENABLE:
1646 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1647 				    HCD_USB3)
1648 					w_value = USB_DEV_STAT_LTM_ENABLED;
1649 				else
1650 					ret_val = -EOPNOTSUPP;
1651 				break;
1652 			default:
1653 				ret_val = -EOPNOTSUPP;
1654 			}
1655 			if (ret_val == 0) {
1656 				dum->devstatus |= (1 << w_value);
1657 				*status = 0;
1658 			}
1659 		} else if (setup->bRequestType == Ep_Request) {
1660 			/* endpoint halt */
1661 			ep2 = find_endpoint(dum, w_index);
1662 			if (!ep2 || ep2->ep.name == ep0name) {
1663 				ret_val = -EOPNOTSUPP;
1664 				break;
1665 			}
1666 			ep2->halted = 1;
1667 			ret_val = 0;
1668 			*status = 0;
1669 		}
1670 		break;
1671 	case USB_REQ_CLEAR_FEATURE:
1672 		if (setup->bRequestType == Dev_Request) {
1673 			ret_val = 0;
1674 			switch (w_value) {
1675 			case USB_DEVICE_REMOTE_WAKEUP:
1676 				w_value = USB_DEVICE_REMOTE_WAKEUP;
1677 				break;
1678 			case USB_DEVICE_U1_ENABLE:
1679 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1680 				    HCD_USB3)
1681 					w_value = USB_DEV_STAT_U1_ENABLED;
1682 				else
1683 					ret_val = -EOPNOTSUPP;
1684 				break;
1685 			case USB_DEVICE_U2_ENABLE:
1686 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1687 				    HCD_USB3)
1688 					w_value = USB_DEV_STAT_U2_ENABLED;
1689 				else
1690 					ret_val = -EOPNOTSUPP;
1691 				break;
1692 			case USB_DEVICE_LTM_ENABLE:
1693 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1694 				    HCD_USB3)
1695 					w_value = USB_DEV_STAT_LTM_ENABLED;
1696 				else
1697 					ret_val = -EOPNOTSUPP;
1698 				break;
1699 			default:
1700 				ret_val = -EOPNOTSUPP;
1701 				break;
1702 			}
1703 			if (ret_val == 0) {
1704 				dum->devstatus &= ~(1 << w_value);
1705 				*status = 0;
1706 			}
1707 		} else if (setup->bRequestType == Ep_Request) {
1708 			/* endpoint halt */
1709 			ep2 = find_endpoint(dum, w_index);
1710 			if (!ep2) {
1711 				ret_val = -EOPNOTSUPP;
1712 				break;
1713 			}
1714 			if (!ep2->wedged)
1715 				ep2->halted = 0;
1716 			ret_val = 0;
1717 			*status = 0;
1718 		}
1719 		break;
1720 	case USB_REQ_GET_STATUS:
1721 		if (setup->bRequestType == Dev_InRequest
1722 				|| setup->bRequestType == Intf_InRequest
1723 				|| setup->bRequestType == Ep_InRequest) {
1724 			char *buf;
1725 			/*
1726 			 * device: remote wakeup, selfpowered
1727 			 * interface: nothing
1728 			 * endpoint: halt
1729 			 */
1730 			buf = (char *)urb->transfer_buffer;
1731 			if (urb->transfer_buffer_length > 0) {
1732 				if (setup->bRequestType == Ep_InRequest) {
1733 					ep2 = find_endpoint(dum, w_index);
1734 					if (!ep2) {
1735 						ret_val = -EOPNOTSUPP;
1736 						break;
1737 					}
1738 					buf[0] = ep2->halted;
1739 				} else if (setup->bRequestType ==
1740 					   Dev_InRequest) {
1741 					buf[0] = (u8)dum->devstatus;
1742 				} else
1743 					buf[0] = 0;
1744 			}
1745 			if (urb->transfer_buffer_length > 1)
1746 				buf[1] = 0;
1747 			urb->actual_length = min_t(u32, 2,
1748 				urb->transfer_buffer_length);
1749 			ret_val = 0;
1750 			*status = 0;
1751 		}
1752 		break;
1753 	}
1754 	return ret_val;
1755 }
1756 
1757 /*
1758  * Drive both sides of the transfers; looks like irq handlers to both
1759  * drivers except that the callbacks are invoked from soft interrupt
1760  * context.
1761  */
1762 static void dummy_timer(struct timer_list *t)
1763 {
1764 	struct dummy_hcd	*dum_hcd = from_timer(dum_hcd, t, timer);
1765 	struct dummy		*dum = dum_hcd->dum;
1766 	struct urbp		*urbp, *tmp;
1767 	unsigned long		flags;
1768 	int			limit, total;
1769 	int			i;
1770 
1771 	/* simplistic model for one frame's bandwidth */
1772 	/* FIXME: account for transaction and packet overhead */
1773 	switch (dum->gadget.speed) {
1774 	case USB_SPEED_LOW:
1775 		total = 8/*bytes*/ * 12/*packets*/;
1776 		break;
1777 	case USB_SPEED_FULL:
1778 		total = 64/*bytes*/ * 19/*packets*/;
1779 		break;
1780 	case USB_SPEED_HIGH:
1781 		total = 512/*bytes*/ * 13/*packets*/ * 8/*uframes*/;
1782 		break;
1783 	case USB_SPEED_SUPER:
1784 		/* Bus speed is 500000 bytes/ms, so use a little less */
1785 		total = 490000;
1786 		break;
1787 	default:	/* Can't happen */
1788 		dev_err(dummy_dev(dum_hcd), "bogus device speed\n");
1789 		total = 0;
1790 		break;
1791 	}
1792 
1793 	/* FIXME if HZ != 1000 this will probably misbehave ... */
1794 
1795 	/* look at each urb queued by the host side driver */
1796 	spin_lock_irqsave(&dum->lock, flags);
1797 
1798 	if (!dum_hcd->udev) {
1799 		dev_err(dummy_dev(dum_hcd),
1800 				"timer fired with no URBs pending?\n");
1801 		spin_unlock_irqrestore(&dum->lock, flags);
1802 		return;
1803 	}
1804 	dum_hcd->next_frame_urbp = NULL;
1805 
1806 	for (i = 0; i < DUMMY_ENDPOINTS; i++) {
1807 		if (!ep_info[i].name)
1808 			break;
1809 		dum->ep[i].already_seen = 0;
1810 	}
1811 
1812 restart:
1813 	list_for_each_entry_safe(urbp, tmp, &dum_hcd->urbp_list, urbp_list) {
1814 		struct urb		*urb;
1815 		struct dummy_request	*req;
1816 		u8			address;
1817 		struct dummy_ep		*ep = NULL;
1818 		int			status = -EINPROGRESS;
1819 
1820 		/* stop when we reach URBs queued after the timer interrupt */
1821 		if (urbp == dum_hcd->next_frame_urbp)
1822 			break;
1823 
1824 		urb = urbp->urb;
1825 		if (urb->unlinked)
1826 			goto return_urb;
1827 		else if (dum_hcd->rh_state != DUMMY_RH_RUNNING)
1828 			continue;
1829 
1830 		/* Used up this frame's bandwidth? */
1831 		if (total <= 0)
1832 			continue;
1833 
1834 		/* find the gadget's ep for this request (if configured) */
1835 		address = usb_pipeendpoint (urb->pipe);
1836 		if (usb_urb_dir_in(urb))
1837 			address |= USB_DIR_IN;
1838 		ep = find_endpoint(dum, address);
1839 		if (!ep) {
1840 			/* set_configuration() disagreement */
1841 			dev_dbg(dummy_dev(dum_hcd),
1842 				"no ep configured for urb %p\n",
1843 				urb);
1844 			status = -EPROTO;
1845 			goto return_urb;
1846 		}
1847 
1848 		if (ep->already_seen)
1849 			continue;
1850 		ep->already_seen = 1;
1851 		if (ep == &dum->ep[0] && urb->error_count) {
1852 			ep->setup_stage = 1;	/* a new urb */
1853 			urb->error_count = 0;
1854 		}
1855 		if (ep->halted && !ep->setup_stage) {
1856 			/* NOTE: must not be iso! */
1857 			dev_dbg(dummy_dev(dum_hcd), "ep %s halted, urb %p\n",
1858 					ep->ep.name, urb);
1859 			status = -EPIPE;
1860 			goto return_urb;
1861 		}
1862 		/* FIXME make sure both ends agree on maxpacket */
1863 
1864 		/* handle control requests */
1865 		if (ep == &dum->ep[0] && ep->setup_stage) {
1866 			struct usb_ctrlrequest		setup;
1867 			int				value = 1;
1868 
1869 			setup = *(struct usb_ctrlrequest *) urb->setup_packet;
1870 			/* paranoia, in case of stale queued data */
1871 			list_for_each_entry(req, &ep->queue, queue) {
1872 				list_del_init(&req->queue);
1873 				req->req.status = -EOVERFLOW;
1874 				dev_dbg(udc_dev(dum), "stale req = %p\n",
1875 						req);
1876 
1877 				spin_unlock(&dum->lock);
1878 				usb_gadget_giveback_request(&ep->ep, &req->req);
1879 				spin_lock(&dum->lock);
1880 				ep->already_seen = 0;
1881 				goto restart;
1882 			}
1883 
1884 			/* gadget driver never sees set_address or operations
1885 			 * on standard feature flags.  some hardware doesn't
1886 			 * even expose them.
1887 			 */
1888 			ep->last_io = jiffies;
1889 			ep->setup_stage = 0;
1890 			ep->halted = 0;
1891 
1892 			value = handle_control_request(dum_hcd, urb, &setup,
1893 						       &status);
1894 
1895 			/* gadget driver handles all other requests.  block
1896 			 * until setup() returns; no reentrancy issues etc.
1897 			 */
1898 			if (value > 0) {
1899 				++dum->callback_usage;
1900 				spin_unlock(&dum->lock);
1901 				value = dum->driver->setup(&dum->gadget,
1902 						&setup);
1903 				spin_lock(&dum->lock);
1904 				--dum->callback_usage;
1905 
1906 				if (value >= 0) {
1907 					/* no delays (max 64KB data stage) */
1908 					limit = 64*1024;
1909 					goto treat_control_like_bulk;
1910 				}
1911 				/* error, see below */
1912 			}
1913 
1914 			if (value < 0) {
1915 				if (value != -EOPNOTSUPP)
1916 					dev_dbg(udc_dev(dum),
1917 						"setup --> %d\n",
1918 						value);
1919 				status = -EPIPE;
1920 				urb->actual_length = 0;
1921 			}
1922 
1923 			goto return_urb;
1924 		}
1925 
1926 		/* non-control requests */
1927 		limit = total;
1928 		switch (usb_pipetype(urb->pipe)) {
1929 		case PIPE_ISOCHRONOUS:
1930 			/*
1931 			 * We don't support isochronous.  But if we did,
1932 			 * here are some of the issues we'd have to face:
1933 			 *
1934 			 * Is it urb->interval since the last xfer?
1935 			 * Use urb->iso_frame_desc[i].
1936 			 * Complete whether or not ep has requests queued.
1937 			 * Report random errors, to debug drivers.
1938 			 */
1939 			limit = max(limit, periodic_bytes(dum, ep));
1940 			status = -EINVAL;	/* fail all xfers */
1941 			break;
1942 
1943 		case PIPE_INTERRUPT:
1944 			/* FIXME is it urb->interval since the last xfer?
1945 			 * this almost certainly polls too fast.
1946 			 */
1947 			limit = max(limit, periodic_bytes(dum, ep));
1948 			fallthrough;
1949 
1950 		default:
1951 treat_control_like_bulk:
1952 			ep->last_io = jiffies;
1953 			total -= transfer(dum_hcd, urb, ep, limit, &status);
1954 			break;
1955 		}
1956 
1957 		/* incomplete transfer? */
1958 		if (status == -EINPROGRESS)
1959 			continue;
1960 
1961 return_urb:
1962 		list_del(&urbp->urbp_list);
1963 		kfree(urbp);
1964 		if (ep)
1965 			ep->already_seen = ep->setup_stage = 0;
1966 
1967 		usb_hcd_unlink_urb_from_ep(dummy_hcd_to_hcd(dum_hcd), urb);
1968 		spin_unlock(&dum->lock);
1969 		usb_hcd_giveback_urb(dummy_hcd_to_hcd(dum_hcd), urb, status);
1970 		spin_lock(&dum->lock);
1971 
1972 		goto restart;
1973 	}
1974 
1975 	if (list_empty(&dum_hcd->urbp_list)) {
1976 		usb_put_dev(dum_hcd->udev);
1977 		dum_hcd->udev = NULL;
1978 	} else if (dum_hcd->rh_state == DUMMY_RH_RUNNING) {
1979 		/* want a 1 msec delay here */
1980 		mod_timer(&dum_hcd->timer, jiffies + msecs_to_jiffies(1));
1981 	}
1982 
1983 	spin_unlock_irqrestore(&dum->lock, flags);
1984 }
1985 
1986 /*-------------------------------------------------------------------------*/
1987 
1988 #define PORT_C_MASK \
1989 	((USB_PORT_STAT_C_CONNECTION \
1990 	| USB_PORT_STAT_C_ENABLE \
1991 	| USB_PORT_STAT_C_SUSPEND \
1992 	| USB_PORT_STAT_C_OVERCURRENT \
1993 	| USB_PORT_STAT_C_RESET) << 16)
1994 
1995 static int dummy_hub_status(struct usb_hcd *hcd, char *buf)
1996 {
1997 	struct dummy_hcd	*dum_hcd;
1998 	unsigned long		flags;
1999 	int			retval = 0;
2000 
2001 	dum_hcd = hcd_to_dummy_hcd(hcd);
2002 
2003 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2004 	if (!HCD_HW_ACCESSIBLE(hcd))
2005 		goto done;
2006 
2007 	if (dum_hcd->resuming && time_after_eq(jiffies, dum_hcd->re_timeout)) {
2008 		dum_hcd->port_status |= (USB_PORT_STAT_C_SUSPEND << 16);
2009 		dum_hcd->port_status &= ~USB_PORT_STAT_SUSPEND;
2010 		set_link_state(dum_hcd);
2011 	}
2012 
2013 	if ((dum_hcd->port_status & PORT_C_MASK) != 0) {
2014 		*buf = (1 << 1);
2015 		dev_dbg(dummy_dev(dum_hcd), "port status 0x%08x has changes\n",
2016 				dum_hcd->port_status);
2017 		retval = 1;
2018 		if (dum_hcd->rh_state == DUMMY_RH_SUSPENDED)
2019 			usb_hcd_resume_root_hub(hcd);
2020 	}
2021 done:
2022 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2023 	return retval;
2024 }
2025 
2026 /* usb 3.0 root hub device descriptor */
2027 static struct {
2028 	struct usb_bos_descriptor bos;
2029 	struct usb_ss_cap_descriptor ss_cap;
2030 } __packed usb3_bos_desc = {
2031 
2032 	.bos = {
2033 		.bLength		= USB_DT_BOS_SIZE,
2034 		.bDescriptorType	= USB_DT_BOS,
2035 		.wTotalLength		= cpu_to_le16(sizeof(usb3_bos_desc)),
2036 		.bNumDeviceCaps		= 1,
2037 	},
2038 	.ss_cap = {
2039 		.bLength		= USB_DT_USB_SS_CAP_SIZE,
2040 		.bDescriptorType	= USB_DT_DEVICE_CAPABILITY,
2041 		.bDevCapabilityType	= USB_SS_CAP_TYPE,
2042 		.wSpeedSupported	= cpu_to_le16(USB_5GBPS_OPERATION),
2043 		.bFunctionalitySupport	= ilog2(USB_5GBPS_OPERATION),
2044 	},
2045 };
2046 
2047 static inline void
2048 ss_hub_descriptor(struct usb_hub_descriptor *desc)
2049 {
2050 	memset(desc, 0, sizeof *desc);
2051 	desc->bDescriptorType = USB_DT_SS_HUB;
2052 	desc->bDescLength = 12;
2053 	desc->wHubCharacteristics = cpu_to_le16(
2054 			HUB_CHAR_INDV_PORT_LPSM |
2055 			HUB_CHAR_COMMON_OCPM);
2056 	desc->bNbrPorts = 1;
2057 	desc->u.ss.bHubHdrDecLat = 0x04; /* Worst case: 0.4 micro sec*/
2058 	desc->u.ss.DeviceRemovable = 0;
2059 }
2060 
2061 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
2062 {
2063 	memset(desc, 0, sizeof *desc);
2064 	desc->bDescriptorType = USB_DT_HUB;
2065 	desc->bDescLength = 9;
2066 	desc->wHubCharacteristics = cpu_to_le16(
2067 			HUB_CHAR_INDV_PORT_LPSM |
2068 			HUB_CHAR_COMMON_OCPM);
2069 	desc->bNbrPorts = 1;
2070 	desc->u.hs.DeviceRemovable[0] = 0;
2071 	desc->u.hs.DeviceRemovable[1] = 0xff;	/* PortPwrCtrlMask */
2072 }
2073 
2074 static int dummy_hub_control(
2075 	struct usb_hcd	*hcd,
2076 	u16		typeReq,
2077 	u16		wValue,
2078 	u16		wIndex,
2079 	char		*buf,
2080 	u16		wLength
2081 ) {
2082 	struct dummy_hcd *dum_hcd;
2083 	int		retval = 0;
2084 	unsigned long	flags;
2085 
2086 	if (!HCD_HW_ACCESSIBLE(hcd))
2087 		return -ETIMEDOUT;
2088 
2089 	dum_hcd = hcd_to_dummy_hcd(hcd);
2090 
2091 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2092 	switch (typeReq) {
2093 	case ClearHubFeature:
2094 		break;
2095 	case ClearPortFeature:
2096 		switch (wValue) {
2097 		case USB_PORT_FEAT_SUSPEND:
2098 			if (hcd->speed == HCD_USB3) {
2099 				dev_dbg(dummy_dev(dum_hcd),
2100 					 "USB_PORT_FEAT_SUSPEND req not "
2101 					 "supported for USB 3.0 roothub\n");
2102 				goto error;
2103 			}
2104 			if (dum_hcd->port_status & USB_PORT_STAT_SUSPEND) {
2105 				/* 20msec resume signaling */
2106 				dum_hcd->resuming = 1;
2107 				dum_hcd->re_timeout = jiffies +
2108 						msecs_to_jiffies(20);
2109 			}
2110 			break;
2111 		case USB_PORT_FEAT_POWER:
2112 			dev_dbg(dummy_dev(dum_hcd), "power-off\n");
2113 			if (hcd->speed == HCD_USB3)
2114 				dum_hcd->port_status &= ~USB_SS_PORT_STAT_POWER;
2115 			else
2116 				dum_hcd->port_status &= ~USB_PORT_STAT_POWER;
2117 			set_link_state(dum_hcd);
2118 			break;
2119 		default:
2120 			dum_hcd->port_status &= ~(1 << wValue);
2121 			set_link_state(dum_hcd);
2122 		}
2123 		break;
2124 	case GetHubDescriptor:
2125 		if (hcd->speed == HCD_USB3 &&
2126 				(wLength < USB_DT_SS_HUB_SIZE ||
2127 				 wValue != (USB_DT_SS_HUB << 8))) {
2128 			dev_dbg(dummy_dev(dum_hcd),
2129 				"Wrong hub descriptor type for "
2130 				"USB 3.0 roothub.\n");
2131 			goto error;
2132 		}
2133 		if (hcd->speed == HCD_USB3)
2134 			ss_hub_descriptor((struct usb_hub_descriptor *) buf);
2135 		else
2136 			hub_descriptor((struct usb_hub_descriptor *) buf);
2137 		break;
2138 
2139 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
2140 		if (hcd->speed != HCD_USB3)
2141 			goto error;
2142 
2143 		if ((wValue >> 8) != USB_DT_BOS)
2144 			goto error;
2145 
2146 		memcpy(buf, &usb3_bos_desc, sizeof(usb3_bos_desc));
2147 		retval = sizeof(usb3_bos_desc);
2148 		break;
2149 
2150 	case GetHubStatus:
2151 		*(__le32 *) buf = cpu_to_le32(0);
2152 		break;
2153 	case GetPortStatus:
2154 		if (wIndex != 1)
2155 			retval = -EPIPE;
2156 
2157 		/* whoever resets or resumes must GetPortStatus to
2158 		 * complete it!!
2159 		 */
2160 		if (dum_hcd->resuming &&
2161 				time_after_eq(jiffies, dum_hcd->re_timeout)) {
2162 			dum_hcd->port_status |= (USB_PORT_STAT_C_SUSPEND << 16);
2163 			dum_hcd->port_status &= ~USB_PORT_STAT_SUSPEND;
2164 		}
2165 		if ((dum_hcd->port_status & USB_PORT_STAT_RESET) != 0 &&
2166 				time_after_eq(jiffies, dum_hcd->re_timeout)) {
2167 			dum_hcd->port_status |= (USB_PORT_STAT_C_RESET << 16);
2168 			dum_hcd->port_status &= ~USB_PORT_STAT_RESET;
2169 			if (dum_hcd->dum->pullup) {
2170 				dum_hcd->port_status |= USB_PORT_STAT_ENABLE;
2171 
2172 				if (hcd->speed < HCD_USB3) {
2173 					switch (dum_hcd->dum->gadget.speed) {
2174 					case USB_SPEED_HIGH:
2175 						dum_hcd->port_status |=
2176 						      USB_PORT_STAT_HIGH_SPEED;
2177 						break;
2178 					case USB_SPEED_LOW:
2179 						dum_hcd->dum->gadget.ep0->
2180 							maxpacket = 8;
2181 						dum_hcd->port_status |=
2182 							USB_PORT_STAT_LOW_SPEED;
2183 						break;
2184 					default:
2185 						break;
2186 					}
2187 				}
2188 			}
2189 		}
2190 		set_link_state(dum_hcd);
2191 		((__le16 *) buf)[0] = cpu_to_le16(dum_hcd->port_status);
2192 		((__le16 *) buf)[1] = cpu_to_le16(dum_hcd->port_status >> 16);
2193 		break;
2194 	case SetHubFeature:
2195 		retval = -EPIPE;
2196 		break;
2197 	case SetPortFeature:
2198 		switch (wValue) {
2199 		case USB_PORT_FEAT_LINK_STATE:
2200 			if (hcd->speed != HCD_USB3) {
2201 				dev_dbg(dummy_dev(dum_hcd),
2202 					 "USB_PORT_FEAT_LINK_STATE req not "
2203 					 "supported for USB 2.0 roothub\n");
2204 				goto error;
2205 			}
2206 			/*
2207 			 * Since this is dummy we don't have an actual link so
2208 			 * there is nothing to do for the SET_LINK_STATE cmd
2209 			 */
2210 			break;
2211 		case USB_PORT_FEAT_U1_TIMEOUT:
2212 		case USB_PORT_FEAT_U2_TIMEOUT:
2213 			/* TODO: add suspend/resume support! */
2214 			if (hcd->speed != HCD_USB3) {
2215 				dev_dbg(dummy_dev(dum_hcd),
2216 					 "USB_PORT_FEAT_U1/2_TIMEOUT req not "
2217 					 "supported for USB 2.0 roothub\n");
2218 				goto error;
2219 			}
2220 			break;
2221 		case USB_PORT_FEAT_SUSPEND:
2222 			/* Applicable only for USB2.0 hub */
2223 			if (hcd->speed == HCD_USB3) {
2224 				dev_dbg(dummy_dev(dum_hcd),
2225 					 "USB_PORT_FEAT_SUSPEND req not "
2226 					 "supported for USB 3.0 roothub\n");
2227 				goto error;
2228 			}
2229 			if (dum_hcd->active) {
2230 				dum_hcd->port_status |= USB_PORT_STAT_SUSPEND;
2231 
2232 				/* HNP would happen here; for now we
2233 				 * assume b_bus_req is always true.
2234 				 */
2235 				set_link_state(dum_hcd);
2236 				if (((1 << USB_DEVICE_B_HNP_ENABLE)
2237 						& dum_hcd->dum->devstatus) != 0)
2238 					dev_dbg(dummy_dev(dum_hcd),
2239 							"no HNP yet!\n");
2240 			}
2241 			break;
2242 		case USB_PORT_FEAT_POWER:
2243 			if (hcd->speed == HCD_USB3)
2244 				dum_hcd->port_status |= USB_SS_PORT_STAT_POWER;
2245 			else
2246 				dum_hcd->port_status |= USB_PORT_STAT_POWER;
2247 			set_link_state(dum_hcd);
2248 			break;
2249 		case USB_PORT_FEAT_BH_PORT_RESET:
2250 			/* Applicable only for USB3.0 hub */
2251 			if (hcd->speed != HCD_USB3) {
2252 				dev_dbg(dummy_dev(dum_hcd),
2253 					 "USB_PORT_FEAT_BH_PORT_RESET req not "
2254 					 "supported for USB 2.0 roothub\n");
2255 				goto error;
2256 			}
2257 			fallthrough;
2258 		case USB_PORT_FEAT_RESET:
2259 			/* if it's already enabled, disable */
2260 			if (hcd->speed == HCD_USB3) {
2261 				dum_hcd->port_status = 0;
2262 				dum_hcd->port_status =
2263 					(USB_SS_PORT_STAT_POWER |
2264 					 USB_PORT_STAT_CONNECTION |
2265 					 USB_PORT_STAT_RESET);
2266 			} else
2267 				dum_hcd->port_status &= ~(USB_PORT_STAT_ENABLE
2268 					| USB_PORT_STAT_LOW_SPEED
2269 					| USB_PORT_STAT_HIGH_SPEED);
2270 			/*
2271 			 * We want to reset device status. All but the
2272 			 * Self powered feature
2273 			 */
2274 			dum_hcd->dum->devstatus &=
2275 				(1 << USB_DEVICE_SELF_POWERED);
2276 			/*
2277 			 * FIXME USB3.0: what is the correct reset signaling
2278 			 * interval? Is it still 50msec as for HS?
2279 			 */
2280 			dum_hcd->re_timeout = jiffies + msecs_to_jiffies(50);
2281 			fallthrough;
2282 		default:
2283 			if (hcd->speed == HCD_USB3) {
2284 				if ((dum_hcd->port_status &
2285 				     USB_SS_PORT_STAT_POWER) != 0) {
2286 					dum_hcd->port_status |= (1 << wValue);
2287 				}
2288 			} else
2289 				if ((dum_hcd->port_status &
2290 				     USB_PORT_STAT_POWER) != 0) {
2291 					dum_hcd->port_status |= (1 << wValue);
2292 				}
2293 			set_link_state(dum_hcd);
2294 		}
2295 		break;
2296 	case GetPortErrorCount:
2297 		if (hcd->speed != HCD_USB3) {
2298 			dev_dbg(dummy_dev(dum_hcd),
2299 				 "GetPortErrorCount req not "
2300 				 "supported for USB 2.0 roothub\n");
2301 			goto error;
2302 		}
2303 		/* We'll always return 0 since this is a dummy hub */
2304 		*(__le32 *) buf = cpu_to_le32(0);
2305 		break;
2306 	case SetHubDepth:
2307 		if (hcd->speed != HCD_USB3) {
2308 			dev_dbg(dummy_dev(dum_hcd),
2309 				 "SetHubDepth req not supported for "
2310 				 "USB 2.0 roothub\n");
2311 			goto error;
2312 		}
2313 		break;
2314 	default:
2315 		dev_dbg(dummy_dev(dum_hcd),
2316 			"hub control req%04x v%04x i%04x l%d\n",
2317 			typeReq, wValue, wIndex, wLength);
2318 error:
2319 		/* "protocol stall" on error */
2320 		retval = -EPIPE;
2321 	}
2322 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2323 
2324 	if ((dum_hcd->port_status & PORT_C_MASK) != 0)
2325 		usb_hcd_poll_rh_status(hcd);
2326 	return retval;
2327 }
2328 
2329 static int dummy_bus_suspend(struct usb_hcd *hcd)
2330 {
2331 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2332 
2333 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
2334 
2335 	spin_lock_irq(&dum_hcd->dum->lock);
2336 	dum_hcd->rh_state = DUMMY_RH_SUSPENDED;
2337 	set_link_state(dum_hcd);
2338 	hcd->state = HC_STATE_SUSPENDED;
2339 	spin_unlock_irq(&dum_hcd->dum->lock);
2340 	return 0;
2341 }
2342 
2343 static int dummy_bus_resume(struct usb_hcd *hcd)
2344 {
2345 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2346 	int rc = 0;
2347 
2348 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
2349 
2350 	spin_lock_irq(&dum_hcd->dum->lock);
2351 	if (!HCD_HW_ACCESSIBLE(hcd)) {
2352 		rc = -ESHUTDOWN;
2353 	} else {
2354 		dum_hcd->rh_state = DUMMY_RH_RUNNING;
2355 		set_link_state(dum_hcd);
2356 		if (!list_empty(&dum_hcd->urbp_list))
2357 			mod_timer(&dum_hcd->timer, jiffies);
2358 		hcd->state = HC_STATE_RUNNING;
2359 	}
2360 	spin_unlock_irq(&dum_hcd->dum->lock);
2361 	return rc;
2362 }
2363 
2364 /*-------------------------------------------------------------------------*/
2365 
2366 static inline ssize_t show_urb(char *buf, size_t size, struct urb *urb)
2367 {
2368 	int ep = usb_pipeendpoint(urb->pipe);
2369 
2370 	return scnprintf(buf, size,
2371 		"urb/%p %s ep%d%s%s len %d/%d\n",
2372 		urb,
2373 		({ char *s;
2374 		switch (urb->dev->speed) {
2375 		case USB_SPEED_LOW:
2376 			s = "ls";
2377 			break;
2378 		case USB_SPEED_FULL:
2379 			s = "fs";
2380 			break;
2381 		case USB_SPEED_HIGH:
2382 			s = "hs";
2383 			break;
2384 		case USB_SPEED_SUPER:
2385 			s = "ss";
2386 			break;
2387 		default:
2388 			s = "?";
2389 			break;
2390 		 } s; }),
2391 		ep, ep ? (usb_urb_dir_in(urb) ? "in" : "out") : "",
2392 		({ char *s; \
2393 		switch (usb_pipetype(urb->pipe)) { \
2394 		case PIPE_CONTROL: \
2395 			s = ""; \
2396 			break; \
2397 		case PIPE_BULK: \
2398 			s = "-bulk"; \
2399 			break; \
2400 		case PIPE_INTERRUPT: \
2401 			s = "-int"; \
2402 			break; \
2403 		default: \
2404 			s = "-iso"; \
2405 			break; \
2406 		} s; }),
2407 		urb->actual_length, urb->transfer_buffer_length);
2408 }
2409 
2410 static ssize_t urbs_show(struct device *dev, struct device_attribute *attr,
2411 		char *buf)
2412 {
2413 	struct usb_hcd		*hcd = dev_get_drvdata(dev);
2414 	struct dummy_hcd	*dum_hcd = hcd_to_dummy_hcd(hcd);
2415 	struct urbp		*urbp;
2416 	size_t			size = 0;
2417 	unsigned long		flags;
2418 
2419 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2420 	list_for_each_entry(urbp, &dum_hcd->urbp_list, urbp_list) {
2421 		size_t		temp;
2422 
2423 		temp = show_urb(buf, PAGE_SIZE - size, urbp->urb);
2424 		buf += temp;
2425 		size += temp;
2426 	}
2427 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2428 
2429 	return size;
2430 }
2431 static DEVICE_ATTR_RO(urbs);
2432 
2433 static int dummy_start_ss(struct dummy_hcd *dum_hcd)
2434 {
2435 	timer_setup(&dum_hcd->timer, dummy_timer, 0);
2436 	dum_hcd->rh_state = DUMMY_RH_RUNNING;
2437 	dum_hcd->stream_en_ep = 0;
2438 	INIT_LIST_HEAD(&dum_hcd->urbp_list);
2439 	dummy_hcd_to_hcd(dum_hcd)->power_budget = POWER_BUDGET_3;
2440 	dummy_hcd_to_hcd(dum_hcd)->state = HC_STATE_RUNNING;
2441 	dummy_hcd_to_hcd(dum_hcd)->uses_new_polling = 1;
2442 #ifdef CONFIG_USB_OTG
2443 	dummy_hcd_to_hcd(dum_hcd)->self.otg_port = 1;
2444 #endif
2445 	return 0;
2446 
2447 	/* FIXME 'urbs' should be a per-device thing, maybe in usbcore */
2448 	return device_create_file(dummy_dev(dum_hcd), &dev_attr_urbs);
2449 }
2450 
2451 static int dummy_start(struct usb_hcd *hcd)
2452 {
2453 	struct dummy_hcd	*dum_hcd = hcd_to_dummy_hcd(hcd);
2454 
2455 	/*
2456 	 * HOST side init ... we emulate a root hub that'll only ever
2457 	 * talk to one device (the gadget side).  Also appears in sysfs,
2458 	 * just like more familiar pci-based HCDs.
2459 	 */
2460 	if (!usb_hcd_is_primary_hcd(hcd))
2461 		return dummy_start_ss(dum_hcd);
2462 
2463 	spin_lock_init(&dum_hcd->dum->lock);
2464 	timer_setup(&dum_hcd->timer, dummy_timer, 0);
2465 	dum_hcd->rh_state = DUMMY_RH_RUNNING;
2466 
2467 	INIT_LIST_HEAD(&dum_hcd->urbp_list);
2468 
2469 	hcd->power_budget = POWER_BUDGET;
2470 	hcd->state = HC_STATE_RUNNING;
2471 	hcd->uses_new_polling = 1;
2472 
2473 #ifdef CONFIG_USB_OTG
2474 	hcd->self.otg_port = 1;
2475 #endif
2476 
2477 	/* FIXME 'urbs' should be a per-device thing, maybe in usbcore */
2478 	return device_create_file(dummy_dev(dum_hcd), &dev_attr_urbs);
2479 }
2480 
2481 static void dummy_stop(struct usb_hcd *hcd)
2482 {
2483 	device_remove_file(dummy_dev(hcd_to_dummy_hcd(hcd)), &dev_attr_urbs);
2484 	dev_info(dummy_dev(hcd_to_dummy_hcd(hcd)), "stopped\n");
2485 }
2486 
2487 /*-------------------------------------------------------------------------*/
2488 
2489 static int dummy_h_get_frame(struct usb_hcd *hcd)
2490 {
2491 	return dummy_g_get_frame(NULL);
2492 }
2493 
2494 static int dummy_setup(struct usb_hcd *hcd)
2495 {
2496 	struct dummy *dum;
2497 
2498 	dum = *((void **)dev_get_platdata(hcd->self.controller));
2499 	hcd->self.sg_tablesize = ~0;
2500 	if (usb_hcd_is_primary_hcd(hcd)) {
2501 		dum->hs_hcd = hcd_to_dummy_hcd(hcd);
2502 		dum->hs_hcd->dum = dum;
2503 		/*
2504 		 * Mark the first roothub as being USB 2.0.
2505 		 * The USB 3.0 roothub will be registered later by
2506 		 * dummy_hcd_probe()
2507 		 */
2508 		hcd->speed = HCD_USB2;
2509 		hcd->self.root_hub->speed = USB_SPEED_HIGH;
2510 	} else {
2511 		dum->ss_hcd = hcd_to_dummy_hcd(hcd);
2512 		dum->ss_hcd->dum = dum;
2513 		hcd->speed = HCD_USB3;
2514 		hcd->self.root_hub->speed = USB_SPEED_SUPER;
2515 	}
2516 	return 0;
2517 }
2518 
2519 /* Change a group of bulk endpoints to support multiple stream IDs */
2520 static int dummy_alloc_streams(struct usb_hcd *hcd, struct usb_device *udev,
2521 	struct usb_host_endpoint **eps, unsigned int num_eps,
2522 	unsigned int num_streams, gfp_t mem_flags)
2523 {
2524 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2525 	unsigned long flags;
2526 	int max_stream;
2527 	int ret_streams = num_streams;
2528 	unsigned int index;
2529 	unsigned int i;
2530 
2531 	if (!num_eps)
2532 		return -EINVAL;
2533 
2534 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2535 	for (i = 0; i < num_eps; i++) {
2536 		index = dummy_get_ep_idx(&eps[i]->desc);
2537 		if ((1 << index) & dum_hcd->stream_en_ep) {
2538 			ret_streams = -EINVAL;
2539 			goto out;
2540 		}
2541 		max_stream = usb_ss_max_streams(&eps[i]->ss_ep_comp);
2542 		if (!max_stream) {
2543 			ret_streams = -EINVAL;
2544 			goto out;
2545 		}
2546 		if (max_stream < ret_streams) {
2547 			dev_dbg(dummy_dev(dum_hcd), "Ep 0x%x only supports %u "
2548 					"stream IDs.\n",
2549 					eps[i]->desc.bEndpointAddress,
2550 					max_stream);
2551 			ret_streams = max_stream;
2552 		}
2553 	}
2554 
2555 	for (i = 0; i < num_eps; i++) {
2556 		index = dummy_get_ep_idx(&eps[i]->desc);
2557 		dum_hcd->stream_en_ep |= 1 << index;
2558 		set_max_streams_for_pipe(dum_hcd,
2559 				usb_endpoint_num(&eps[i]->desc), ret_streams);
2560 	}
2561 out:
2562 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2563 	return ret_streams;
2564 }
2565 
2566 /* Reverts a group of bulk endpoints back to not using stream IDs. */
2567 static int dummy_free_streams(struct usb_hcd *hcd, struct usb_device *udev,
2568 	struct usb_host_endpoint **eps, unsigned int num_eps,
2569 	gfp_t mem_flags)
2570 {
2571 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2572 	unsigned long flags;
2573 	int ret;
2574 	unsigned int index;
2575 	unsigned int i;
2576 
2577 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2578 	for (i = 0; i < num_eps; i++) {
2579 		index = dummy_get_ep_idx(&eps[i]->desc);
2580 		if (!((1 << index) & dum_hcd->stream_en_ep)) {
2581 			ret = -EINVAL;
2582 			goto out;
2583 		}
2584 	}
2585 
2586 	for (i = 0; i < num_eps; i++) {
2587 		index = dummy_get_ep_idx(&eps[i]->desc);
2588 		dum_hcd->stream_en_ep &= ~(1 << index);
2589 		set_max_streams_for_pipe(dum_hcd,
2590 				usb_endpoint_num(&eps[i]->desc), 0);
2591 	}
2592 	ret = 0;
2593 out:
2594 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2595 	return ret;
2596 }
2597 
2598 static struct hc_driver dummy_hcd = {
2599 	.description =		(char *) driver_name,
2600 	.product_desc =		"Dummy host controller",
2601 	.hcd_priv_size =	sizeof(struct dummy_hcd),
2602 
2603 	.reset =		dummy_setup,
2604 	.start =		dummy_start,
2605 	.stop =			dummy_stop,
2606 
2607 	.urb_enqueue =		dummy_urb_enqueue,
2608 	.urb_dequeue =		dummy_urb_dequeue,
2609 
2610 	.get_frame_number =	dummy_h_get_frame,
2611 
2612 	.hub_status_data =	dummy_hub_status,
2613 	.hub_control =		dummy_hub_control,
2614 	.bus_suspend =		dummy_bus_suspend,
2615 	.bus_resume =		dummy_bus_resume,
2616 
2617 	.alloc_streams =	dummy_alloc_streams,
2618 	.free_streams =		dummy_free_streams,
2619 };
2620 
2621 static int dummy_hcd_probe(struct platform_device *pdev)
2622 {
2623 	struct dummy		*dum;
2624 	struct usb_hcd		*hs_hcd;
2625 	struct usb_hcd		*ss_hcd;
2626 	int			retval;
2627 
2628 	dev_info(&pdev->dev, "%s, driver " DRIVER_VERSION "\n", driver_desc);
2629 	dum = *((void **)dev_get_platdata(&pdev->dev));
2630 
2631 	if (mod_data.is_super_speed)
2632 		dummy_hcd.flags = HCD_USB3 | HCD_SHARED;
2633 	else if (mod_data.is_high_speed)
2634 		dummy_hcd.flags = HCD_USB2;
2635 	else
2636 		dummy_hcd.flags = HCD_USB11;
2637 	hs_hcd = usb_create_hcd(&dummy_hcd, &pdev->dev, dev_name(&pdev->dev));
2638 	if (!hs_hcd)
2639 		return -ENOMEM;
2640 	hs_hcd->has_tt = 1;
2641 
2642 	retval = usb_add_hcd(hs_hcd, 0, 0);
2643 	if (retval)
2644 		goto put_usb2_hcd;
2645 
2646 	if (mod_data.is_super_speed) {
2647 		ss_hcd = usb_create_shared_hcd(&dummy_hcd, &pdev->dev,
2648 					dev_name(&pdev->dev), hs_hcd);
2649 		if (!ss_hcd) {
2650 			retval = -ENOMEM;
2651 			goto dealloc_usb2_hcd;
2652 		}
2653 
2654 		retval = usb_add_hcd(ss_hcd, 0, 0);
2655 		if (retval)
2656 			goto put_usb3_hcd;
2657 	}
2658 	return 0;
2659 
2660 put_usb3_hcd:
2661 	usb_put_hcd(ss_hcd);
2662 dealloc_usb2_hcd:
2663 	usb_remove_hcd(hs_hcd);
2664 put_usb2_hcd:
2665 	usb_put_hcd(hs_hcd);
2666 	dum->hs_hcd = dum->ss_hcd = NULL;
2667 	return retval;
2668 }
2669 
2670 static int dummy_hcd_remove(struct platform_device *pdev)
2671 {
2672 	struct dummy		*dum;
2673 
2674 	dum = hcd_to_dummy_hcd(platform_get_drvdata(pdev))->dum;
2675 
2676 	if (dum->ss_hcd) {
2677 		usb_remove_hcd(dummy_hcd_to_hcd(dum->ss_hcd));
2678 		usb_put_hcd(dummy_hcd_to_hcd(dum->ss_hcd));
2679 	}
2680 
2681 	usb_remove_hcd(dummy_hcd_to_hcd(dum->hs_hcd));
2682 	usb_put_hcd(dummy_hcd_to_hcd(dum->hs_hcd));
2683 
2684 	dum->hs_hcd = NULL;
2685 	dum->ss_hcd = NULL;
2686 
2687 	return 0;
2688 }
2689 
2690 static int dummy_hcd_suspend(struct platform_device *pdev, pm_message_t state)
2691 {
2692 	struct usb_hcd		*hcd;
2693 	struct dummy_hcd	*dum_hcd;
2694 	int			rc = 0;
2695 
2696 	dev_dbg(&pdev->dev, "%s\n", __func__);
2697 
2698 	hcd = platform_get_drvdata(pdev);
2699 	dum_hcd = hcd_to_dummy_hcd(hcd);
2700 	if (dum_hcd->rh_state == DUMMY_RH_RUNNING) {
2701 		dev_warn(&pdev->dev, "Root hub isn't suspended!\n");
2702 		rc = -EBUSY;
2703 	} else
2704 		clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2705 	return rc;
2706 }
2707 
2708 static int dummy_hcd_resume(struct platform_device *pdev)
2709 {
2710 	struct usb_hcd		*hcd;
2711 
2712 	dev_dbg(&pdev->dev, "%s\n", __func__);
2713 
2714 	hcd = platform_get_drvdata(pdev);
2715 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2716 	usb_hcd_poll_rh_status(hcd);
2717 	return 0;
2718 }
2719 
2720 static struct platform_driver dummy_hcd_driver = {
2721 	.probe		= dummy_hcd_probe,
2722 	.remove		= dummy_hcd_remove,
2723 	.suspend	= dummy_hcd_suspend,
2724 	.resume		= dummy_hcd_resume,
2725 	.driver		= {
2726 		.name	= driver_name,
2727 	},
2728 };
2729 
2730 /*-------------------------------------------------------------------------*/
2731 #define MAX_NUM_UDC	32
2732 static struct platform_device *the_udc_pdev[MAX_NUM_UDC];
2733 static struct platform_device *the_hcd_pdev[MAX_NUM_UDC];
2734 
2735 static int __init init(void)
2736 {
2737 	int	retval = -ENOMEM;
2738 	int	i;
2739 	struct	dummy *dum[MAX_NUM_UDC];
2740 
2741 	if (usb_disabled())
2742 		return -ENODEV;
2743 
2744 	if (!mod_data.is_high_speed && mod_data.is_super_speed)
2745 		return -EINVAL;
2746 
2747 	if (mod_data.num < 1 || mod_data.num > MAX_NUM_UDC) {
2748 		pr_err("Number of emulated UDC must be in range of 1...%d\n",
2749 				MAX_NUM_UDC);
2750 		return -EINVAL;
2751 	}
2752 
2753 	for (i = 0; i < mod_data.num; i++) {
2754 		the_hcd_pdev[i] = platform_device_alloc(driver_name, i);
2755 		if (!the_hcd_pdev[i]) {
2756 			i--;
2757 			while (i >= 0)
2758 				platform_device_put(the_hcd_pdev[i--]);
2759 			return retval;
2760 		}
2761 	}
2762 	for (i = 0; i < mod_data.num; i++) {
2763 		the_udc_pdev[i] = platform_device_alloc(gadget_name, i);
2764 		if (!the_udc_pdev[i]) {
2765 			i--;
2766 			while (i >= 0)
2767 				platform_device_put(the_udc_pdev[i--]);
2768 			goto err_alloc_udc;
2769 		}
2770 	}
2771 	for (i = 0; i < mod_data.num; i++) {
2772 		dum[i] = kzalloc(sizeof(struct dummy), GFP_KERNEL);
2773 		if (!dum[i]) {
2774 			retval = -ENOMEM;
2775 			goto err_add_pdata;
2776 		}
2777 		retval = platform_device_add_data(the_hcd_pdev[i], &dum[i],
2778 				sizeof(void *));
2779 		if (retval)
2780 			goto err_add_pdata;
2781 		retval = platform_device_add_data(the_udc_pdev[i], &dum[i],
2782 				sizeof(void *));
2783 		if (retval)
2784 			goto err_add_pdata;
2785 	}
2786 
2787 	retval = platform_driver_register(&dummy_hcd_driver);
2788 	if (retval < 0)
2789 		goto err_add_pdata;
2790 	retval = platform_driver_register(&dummy_udc_driver);
2791 	if (retval < 0)
2792 		goto err_register_udc_driver;
2793 
2794 	for (i = 0; i < mod_data.num; i++) {
2795 		retval = platform_device_add(the_hcd_pdev[i]);
2796 		if (retval < 0) {
2797 			i--;
2798 			while (i >= 0)
2799 				platform_device_del(the_hcd_pdev[i--]);
2800 			goto err_add_hcd;
2801 		}
2802 	}
2803 	for (i = 0; i < mod_data.num; i++) {
2804 		if (!dum[i]->hs_hcd ||
2805 				(!dum[i]->ss_hcd && mod_data.is_super_speed)) {
2806 			/*
2807 			 * The hcd was added successfully but its probe
2808 			 * function failed for some reason.
2809 			 */
2810 			retval = -EINVAL;
2811 			goto err_add_udc;
2812 		}
2813 	}
2814 
2815 	for (i = 0; i < mod_data.num; i++) {
2816 		retval = platform_device_add(the_udc_pdev[i]);
2817 		if (retval < 0) {
2818 			i--;
2819 			while (i >= 0)
2820 				platform_device_del(the_udc_pdev[i--]);
2821 			goto err_add_udc;
2822 		}
2823 	}
2824 
2825 	for (i = 0; i < mod_data.num; i++) {
2826 		if (!platform_get_drvdata(the_udc_pdev[i])) {
2827 			/*
2828 			 * The udc was added successfully but its probe
2829 			 * function failed for some reason.
2830 			 */
2831 			retval = -EINVAL;
2832 			goto err_probe_udc;
2833 		}
2834 	}
2835 	return retval;
2836 
2837 err_probe_udc:
2838 	for (i = 0; i < mod_data.num; i++)
2839 		platform_device_del(the_udc_pdev[i]);
2840 err_add_udc:
2841 	for (i = 0; i < mod_data.num; i++)
2842 		platform_device_del(the_hcd_pdev[i]);
2843 err_add_hcd:
2844 	platform_driver_unregister(&dummy_udc_driver);
2845 err_register_udc_driver:
2846 	platform_driver_unregister(&dummy_hcd_driver);
2847 err_add_pdata:
2848 	for (i = 0; i < mod_data.num; i++)
2849 		kfree(dum[i]);
2850 	for (i = 0; i < mod_data.num; i++)
2851 		platform_device_put(the_udc_pdev[i]);
2852 err_alloc_udc:
2853 	for (i = 0; i < mod_data.num; i++)
2854 		platform_device_put(the_hcd_pdev[i]);
2855 	return retval;
2856 }
2857 module_init(init);
2858 
2859 static void __exit cleanup(void)
2860 {
2861 	int i;
2862 
2863 	for (i = 0; i < mod_data.num; i++) {
2864 		struct dummy *dum;
2865 
2866 		dum = *((void **)dev_get_platdata(&the_udc_pdev[i]->dev));
2867 
2868 		platform_device_unregister(the_udc_pdev[i]);
2869 		platform_device_unregister(the_hcd_pdev[i]);
2870 		kfree(dum);
2871 	}
2872 	platform_driver_unregister(&dummy_udc_driver);
2873 	platform_driver_unregister(&dummy_hcd_driver);
2874 }
2875 module_exit(cleanup);
2876