xref: /openbmc/linux/drivers/usb/gadget/udc/dummy_hcd.c (revision c1cf3d89)
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 			fallthrough;
557 		default:
558 			goto done;
559 		}
560 		break;
561 	case USB_ENDPOINT_XFER_INT:
562 		if (strstr(ep->ep.name, "-iso")) /* bulk is ok */
563 			goto done;
564 		/* real hardware might not handle all packet sizes */
565 		switch (dum->gadget.speed) {
566 		case USB_SPEED_SUPER:
567 		case USB_SPEED_HIGH:
568 			if (max <= 1024)
569 				break;
570 			/* save a return statement */
571 			fallthrough;
572 		case USB_SPEED_FULL:
573 			if (max <= 64)
574 				break;
575 			/* save a return statement */
576 			fallthrough;
577 		default:
578 			if (max <= 8)
579 				break;
580 			goto done;
581 		}
582 		break;
583 	case USB_ENDPOINT_XFER_ISOC:
584 		if (strstr(ep->ep.name, "-bulk")
585 				|| strstr(ep->ep.name, "-int"))
586 			goto done;
587 		/* real hardware might not handle all packet sizes */
588 		switch (dum->gadget.speed) {
589 		case USB_SPEED_SUPER:
590 		case USB_SPEED_HIGH:
591 			if (max <= 1024)
592 				break;
593 			/* save a return statement */
594 			fallthrough;
595 		case USB_SPEED_FULL:
596 			if (max <= 1023)
597 				break;
598 			/* save a return statement */
599 			fallthrough;
600 		default:
601 			goto done;
602 		}
603 		break;
604 	default:
605 		/* few chips support control except on ep0 */
606 		goto done;
607 	}
608 
609 	_ep->maxpacket = max;
610 	if (usb_ss_max_streams(_ep->comp_desc)) {
611 		if (!usb_endpoint_xfer_bulk(desc)) {
612 			dev_err(udc_dev(dum), "Can't enable stream support on "
613 					"non-bulk ep %s\n", _ep->name);
614 			return -EINVAL;
615 		}
616 		ep->stream_en = 1;
617 	}
618 	ep->desc = desc;
619 
620 	dev_dbg(udc_dev(dum), "enabled %s (ep%d%s-%s) maxpacket %d stream %s\n",
621 		_ep->name,
622 		desc->bEndpointAddress & 0x0f,
623 		(desc->bEndpointAddress & USB_DIR_IN) ? "in" : "out",
624 		usb_ep_type_string(usb_endpoint_type(desc)),
625 		max, ep->stream_en ? "enabled" : "disabled");
626 
627 	/* at this point real hardware should be NAKing transfers
628 	 * to that endpoint, until a buffer is queued to it.
629 	 */
630 	ep->halted = ep->wedged = 0;
631 	retval = 0;
632 done:
633 	return retval;
634 }
635 
636 static int dummy_disable(struct usb_ep *_ep)
637 {
638 	struct dummy_ep		*ep;
639 	struct dummy		*dum;
640 	unsigned long		flags;
641 
642 	ep = usb_ep_to_dummy_ep(_ep);
643 	if (!_ep || !ep->desc || _ep->name == ep0name)
644 		return -EINVAL;
645 	dum = ep_to_dummy(ep);
646 
647 	spin_lock_irqsave(&dum->lock, flags);
648 	ep->desc = NULL;
649 	ep->stream_en = 0;
650 	nuke(dum, ep);
651 	spin_unlock_irqrestore(&dum->lock, flags);
652 
653 	dev_dbg(udc_dev(dum), "disabled %s\n", _ep->name);
654 	return 0;
655 }
656 
657 static struct usb_request *dummy_alloc_request(struct usb_ep *_ep,
658 		gfp_t mem_flags)
659 {
660 	struct dummy_request	*req;
661 
662 	if (!_ep)
663 		return NULL;
664 
665 	req = kzalloc(sizeof(*req), mem_flags);
666 	if (!req)
667 		return NULL;
668 	INIT_LIST_HEAD(&req->queue);
669 	return &req->req;
670 }
671 
672 static void dummy_free_request(struct usb_ep *_ep, struct usb_request *_req)
673 {
674 	struct dummy_request	*req;
675 
676 	if (!_ep || !_req) {
677 		WARN_ON(1);
678 		return;
679 	}
680 
681 	req = usb_request_to_dummy_request(_req);
682 	WARN_ON(!list_empty(&req->queue));
683 	kfree(req);
684 }
685 
686 static void fifo_complete(struct usb_ep *ep, struct usb_request *req)
687 {
688 }
689 
690 static int dummy_queue(struct usb_ep *_ep, struct usb_request *_req,
691 		gfp_t mem_flags)
692 {
693 	struct dummy_ep		*ep;
694 	struct dummy_request	*req;
695 	struct dummy		*dum;
696 	struct dummy_hcd	*dum_hcd;
697 	unsigned long		flags;
698 
699 	req = usb_request_to_dummy_request(_req);
700 	if (!_req || !list_empty(&req->queue) || !_req->complete)
701 		return -EINVAL;
702 
703 	ep = usb_ep_to_dummy_ep(_ep);
704 	if (!_ep || (!ep->desc && _ep->name != ep0name))
705 		return -EINVAL;
706 
707 	dum = ep_to_dummy(ep);
708 	dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
709 	if (!dum->driver || !is_enabled(dum_hcd))
710 		return -ESHUTDOWN;
711 
712 #if 0
713 	dev_dbg(udc_dev(dum), "ep %p queue req %p to %s, len %d buf %p\n",
714 			ep, _req, _ep->name, _req->length, _req->buf);
715 #endif
716 	_req->status = -EINPROGRESS;
717 	_req->actual = 0;
718 	spin_lock_irqsave(&dum->lock, flags);
719 
720 	/* implement an emulated single-request FIFO */
721 	if (ep->desc && (ep->desc->bEndpointAddress & USB_DIR_IN) &&
722 			list_empty(&dum->fifo_req.queue) &&
723 			list_empty(&ep->queue) &&
724 			_req->length <= FIFO_SIZE) {
725 		req = &dum->fifo_req;
726 		req->req = *_req;
727 		req->req.buf = dum->fifo_buf;
728 		memcpy(dum->fifo_buf, _req->buf, _req->length);
729 		req->req.context = dum;
730 		req->req.complete = fifo_complete;
731 
732 		list_add_tail(&req->queue, &ep->queue);
733 		spin_unlock(&dum->lock);
734 		_req->actual = _req->length;
735 		_req->status = 0;
736 		usb_gadget_giveback_request(_ep, _req);
737 		spin_lock(&dum->lock);
738 	}  else
739 		list_add_tail(&req->queue, &ep->queue);
740 	spin_unlock_irqrestore(&dum->lock, flags);
741 
742 	/* real hardware would likely enable transfers here, in case
743 	 * it'd been left NAKing.
744 	 */
745 	return 0;
746 }
747 
748 static int dummy_dequeue(struct usb_ep *_ep, struct usb_request *_req)
749 {
750 	struct dummy_ep		*ep;
751 	struct dummy		*dum;
752 	int			retval = -EINVAL;
753 	unsigned long		flags;
754 	struct dummy_request	*req = NULL;
755 
756 	if (!_ep || !_req)
757 		return retval;
758 	ep = usb_ep_to_dummy_ep(_ep);
759 	dum = ep_to_dummy(ep);
760 
761 	if (!dum->driver)
762 		return -ESHUTDOWN;
763 
764 	local_irq_save(flags);
765 	spin_lock(&dum->lock);
766 	list_for_each_entry(req, &ep->queue, queue) {
767 		if (&req->req == _req) {
768 			list_del_init(&req->queue);
769 			_req->status = -ECONNRESET;
770 			retval = 0;
771 			break;
772 		}
773 	}
774 	spin_unlock(&dum->lock);
775 
776 	if (retval == 0) {
777 		dev_dbg(udc_dev(dum),
778 				"dequeued req %p from %s, len %d buf %p\n",
779 				req, _ep->name, _req->length, _req->buf);
780 		usb_gadget_giveback_request(_ep, _req);
781 	}
782 	local_irq_restore(flags);
783 	return retval;
784 }
785 
786 static int
787 dummy_set_halt_and_wedge(struct usb_ep *_ep, int value, int wedged)
788 {
789 	struct dummy_ep		*ep;
790 	struct dummy		*dum;
791 
792 	if (!_ep)
793 		return -EINVAL;
794 	ep = usb_ep_to_dummy_ep(_ep);
795 	dum = ep_to_dummy(ep);
796 	if (!dum->driver)
797 		return -ESHUTDOWN;
798 	if (!value)
799 		ep->halted = ep->wedged = 0;
800 	else if (ep->desc && (ep->desc->bEndpointAddress & USB_DIR_IN) &&
801 			!list_empty(&ep->queue))
802 		return -EAGAIN;
803 	else {
804 		ep->halted = 1;
805 		if (wedged)
806 			ep->wedged = 1;
807 	}
808 	/* FIXME clear emulated data toggle too */
809 	return 0;
810 }
811 
812 static int
813 dummy_set_halt(struct usb_ep *_ep, int value)
814 {
815 	return dummy_set_halt_and_wedge(_ep, value, 0);
816 }
817 
818 static int dummy_set_wedge(struct usb_ep *_ep)
819 {
820 	if (!_ep || _ep->name == ep0name)
821 		return -EINVAL;
822 	return dummy_set_halt_and_wedge(_ep, 1, 1);
823 }
824 
825 static const struct usb_ep_ops dummy_ep_ops = {
826 	.enable		= dummy_enable,
827 	.disable	= dummy_disable,
828 
829 	.alloc_request	= dummy_alloc_request,
830 	.free_request	= dummy_free_request,
831 
832 	.queue		= dummy_queue,
833 	.dequeue	= dummy_dequeue,
834 
835 	.set_halt	= dummy_set_halt,
836 	.set_wedge	= dummy_set_wedge,
837 };
838 
839 /*-------------------------------------------------------------------------*/
840 
841 /* there are both host and device side versions of this call ... */
842 static int dummy_g_get_frame(struct usb_gadget *_gadget)
843 {
844 	struct timespec64 ts64;
845 
846 	ktime_get_ts64(&ts64);
847 	return ts64.tv_nsec / NSEC_PER_MSEC;
848 }
849 
850 static int dummy_wakeup(struct usb_gadget *_gadget)
851 {
852 	struct dummy_hcd *dum_hcd;
853 
854 	dum_hcd = gadget_to_dummy_hcd(_gadget);
855 	if (!(dum_hcd->dum->devstatus & ((1 << USB_DEVICE_B_HNP_ENABLE)
856 				| (1 << USB_DEVICE_REMOTE_WAKEUP))))
857 		return -EINVAL;
858 	if ((dum_hcd->port_status & USB_PORT_STAT_CONNECTION) == 0)
859 		return -ENOLINK;
860 	if ((dum_hcd->port_status & USB_PORT_STAT_SUSPEND) == 0 &&
861 			 dum_hcd->rh_state != DUMMY_RH_SUSPENDED)
862 		return -EIO;
863 
864 	/* FIXME: What if the root hub is suspended but the port isn't? */
865 
866 	/* hub notices our request, issues downstream resume, etc */
867 	dum_hcd->resuming = 1;
868 	dum_hcd->re_timeout = jiffies + msecs_to_jiffies(20);
869 	mod_timer(&dummy_hcd_to_hcd(dum_hcd)->rh_timer, dum_hcd->re_timeout);
870 	return 0;
871 }
872 
873 static int dummy_set_selfpowered(struct usb_gadget *_gadget, int value)
874 {
875 	struct dummy	*dum;
876 
877 	_gadget->is_selfpowered = (value != 0);
878 	dum = gadget_to_dummy_hcd(_gadget)->dum;
879 	if (value)
880 		dum->devstatus |= (1 << USB_DEVICE_SELF_POWERED);
881 	else
882 		dum->devstatus &= ~(1 << USB_DEVICE_SELF_POWERED);
883 	return 0;
884 }
885 
886 static void dummy_udc_update_ep0(struct dummy *dum)
887 {
888 	if (dum->gadget.speed == USB_SPEED_SUPER)
889 		dum->ep[0].ep.maxpacket = 9;
890 	else
891 		dum->ep[0].ep.maxpacket = 64;
892 }
893 
894 static int dummy_pullup(struct usb_gadget *_gadget, int value)
895 {
896 	struct dummy_hcd *dum_hcd;
897 	struct dummy	*dum;
898 	unsigned long	flags;
899 
900 	dum = gadget_dev_to_dummy(&_gadget->dev);
901 	dum_hcd = gadget_to_dummy_hcd(_gadget);
902 
903 	spin_lock_irqsave(&dum->lock, flags);
904 	dum->pullup = (value != 0);
905 	set_link_state(dum_hcd);
906 	spin_unlock_irqrestore(&dum->lock, flags);
907 
908 	usb_hcd_poll_rh_status(dummy_hcd_to_hcd(dum_hcd));
909 	return 0;
910 }
911 
912 static void dummy_udc_set_speed(struct usb_gadget *_gadget,
913 		enum usb_device_speed speed)
914 {
915 	struct dummy	*dum;
916 
917 	dum = gadget_dev_to_dummy(&_gadget->dev);
918 	dum->gadget.speed = speed;
919 	dummy_udc_update_ep0(dum);
920 }
921 
922 static int dummy_udc_start(struct usb_gadget *g,
923 		struct usb_gadget_driver *driver);
924 static int dummy_udc_stop(struct usb_gadget *g);
925 
926 static const struct usb_gadget_ops dummy_ops = {
927 	.get_frame	= dummy_g_get_frame,
928 	.wakeup		= dummy_wakeup,
929 	.set_selfpowered = dummy_set_selfpowered,
930 	.pullup		= dummy_pullup,
931 	.udc_start	= dummy_udc_start,
932 	.udc_stop	= dummy_udc_stop,
933 	.udc_set_speed	= dummy_udc_set_speed,
934 };
935 
936 /*-------------------------------------------------------------------------*/
937 
938 /* "function" sysfs attribute */
939 static ssize_t function_show(struct device *dev, struct device_attribute *attr,
940 		char *buf)
941 {
942 	struct dummy	*dum = gadget_dev_to_dummy(dev);
943 
944 	if (!dum->driver || !dum->driver->function)
945 		return 0;
946 	return scnprintf(buf, PAGE_SIZE, "%s\n", dum->driver->function);
947 }
948 static DEVICE_ATTR_RO(function);
949 
950 /*-------------------------------------------------------------------------*/
951 
952 /*
953  * Driver registration/unregistration.
954  *
955  * This is basically hardware-specific; there's usually only one real USB
956  * device (not host) controller since that's how USB devices are intended
957  * to work.  So most implementations of these api calls will rely on the
958  * fact that only one driver will ever bind to the hardware.  But curious
959  * hardware can be built with discrete components, so the gadget API doesn't
960  * require that assumption.
961  *
962  * For this emulator, it might be convenient to create a usb device
963  * for each driver that registers:  just add to a big root hub.
964  */
965 
966 static int dummy_udc_start(struct usb_gadget *g,
967 		struct usb_gadget_driver *driver)
968 {
969 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(g);
970 	struct dummy		*dum = dum_hcd->dum;
971 
972 	switch (g->speed) {
973 	/* All the speeds we support */
974 	case USB_SPEED_LOW:
975 	case USB_SPEED_FULL:
976 	case USB_SPEED_HIGH:
977 	case USB_SPEED_SUPER:
978 		break;
979 	default:
980 		dev_err(dummy_dev(dum_hcd), "Unsupported driver max speed %d\n",
981 				driver->max_speed);
982 		return -EINVAL;
983 	}
984 
985 	/*
986 	 * DEVICE side init ... the layer above hardware, which
987 	 * can't enumerate without help from the driver we're binding.
988 	 */
989 
990 	spin_lock_irq(&dum->lock);
991 	dum->devstatus = 0;
992 	dum->driver = driver;
993 	dum->ints_enabled = 1;
994 	spin_unlock_irq(&dum->lock);
995 
996 	return 0;
997 }
998 
999 static int dummy_udc_stop(struct usb_gadget *g)
1000 {
1001 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(g);
1002 	struct dummy		*dum = dum_hcd->dum;
1003 
1004 	spin_lock_irq(&dum->lock);
1005 	dum->ints_enabled = 0;
1006 	stop_activity(dum);
1007 
1008 	/* emulate synchronize_irq(): wait for callbacks to finish */
1009 	while (dum->callback_usage > 0) {
1010 		spin_unlock_irq(&dum->lock);
1011 		usleep_range(1000, 2000);
1012 		spin_lock_irq(&dum->lock);
1013 	}
1014 
1015 	dum->driver = NULL;
1016 	spin_unlock_irq(&dum->lock);
1017 
1018 	return 0;
1019 }
1020 
1021 #undef is_enabled
1022 
1023 /* The gadget structure is stored inside the hcd structure and will be
1024  * released along with it. */
1025 static void init_dummy_udc_hw(struct dummy *dum)
1026 {
1027 	int i;
1028 
1029 	INIT_LIST_HEAD(&dum->gadget.ep_list);
1030 	for (i = 0; i < DUMMY_ENDPOINTS; i++) {
1031 		struct dummy_ep	*ep = &dum->ep[i];
1032 
1033 		if (!ep_info[i].name)
1034 			break;
1035 		ep->ep.name = ep_info[i].name;
1036 		ep->ep.caps = ep_info[i].caps;
1037 		ep->ep.ops = &dummy_ep_ops;
1038 		list_add_tail(&ep->ep.ep_list, &dum->gadget.ep_list);
1039 		ep->halted = ep->wedged = ep->already_seen =
1040 				ep->setup_stage = 0;
1041 		usb_ep_set_maxpacket_limit(&ep->ep, ~0);
1042 		ep->ep.max_streams = 16;
1043 		ep->last_io = jiffies;
1044 		ep->gadget = &dum->gadget;
1045 		ep->desc = NULL;
1046 		INIT_LIST_HEAD(&ep->queue);
1047 	}
1048 
1049 	dum->gadget.ep0 = &dum->ep[0].ep;
1050 	list_del_init(&dum->ep[0].ep.ep_list);
1051 	INIT_LIST_HEAD(&dum->fifo_req.queue);
1052 
1053 #ifdef CONFIG_USB_OTG
1054 	dum->gadget.is_otg = 1;
1055 #endif
1056 }
1057 
1058 static int dummy_udc_probe(struct platform_device *pdev)
1059 {
1060 	struct dummy	*dum;
1061 	int		rc;
1062 
1063 	dum = *((void **)dev_get_platdata(&pdev->dev));
1064 	/* Clear usb_gadget region for new registration to udc-core */
1065 	memzero_explicit(&dum->gadget, sizeof(struct usb_gadget));
1066 	dum->gadget.name = gadget_name;
1067 	dum->gadget.ops = &dummy_ops;
1068 	if (mod_data.is_super_speed)
1069 		dum->gadget.max_speed = USB_SPEED_SUPER;
1070 	else if (mod_data.is_high_speed)
1071 		dum->gadget.max_speed = USB_SPEED_HIGH;
1072 	else
1073 		dum->gadget.max_speed = USB_SPEED_FULL;
1074 
1075 	dum->gadget.dev.parent = &pdev->dev;
1076 	init_dummy_udc_hw(dum);
1077 
1078 	rc = usb_add_gadget_udc(&pdev->dev, &dum->gadget);
1079 	if (rc < 0)
1080 		goto err_udc;
1081 
1082 	rc = device_create_file(&dum->gadget.dev, &dev_attr_function);
1083 	if (rc < 0)
1084 		goto err_dev;
1085 	platform_set_drvdata(pdev, dum);
1086 	return rc;
1087 
1088 err_dev:
1089 	usb_del_gadget_udc(&dum->gadget);
1090 err_udc:
1091 	return rc;
1092 }
1093 
1094 static int dummy_udc_remove(struct platform_device *pdev)
1095 {
1096 	struct dummy	*dum = platform_get_drvdata(pdev);
1097 
1098 	device_remove_file(&dum->gadget.dev, &dev_attr_function);
1099 	usb_del_gadget_udc(&dum->gadget);
1100 	return 0;
1101 }
1102 
1103 static void dummy_udc_pm(struct dummy *dum, struct dummy_hcd *dum_hcd,
1104 		int suspend)
1105 {
1106 	spin_lock_irq(&dum->lock);
1107 	dum->udc_suspended = suspend;
1108 	set_link_state(dum_hcd);
1109 	spin_unlock_irq(&dum->lock);
1110 }
1111 
1112 static int dummy_udc_suspend(struct platform_device *pdev, pm_message_t state)
1113 {
1114 	struct dummy		*dum = platform_get_drvdata(pdev);
1115 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
1116 
1117 	dev_dbg(&pdev->dev, "%s\n", __func__);
1118 	dummy_udc_pm(dum, dum_hcd, 1);
1119 	usb_hcd_poll_rh_status(dummy_hcd_to_hcd(dum_hcd));
1120 	return 0;
1121 }
1122 
1123 static int dummy_udc_resume(struct platform_device *pdev)
1124 {
1125 	struct dummy		*dum = platform_get_drvdata(pdev);
1126 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
1127 
1128 	dev_dbg(&pdev->dev, "%s\n", __func__);
1129 	dummy_udc_pm(dum, dum_hcd, 0);
1130 	usb_hcd_poll_rh_status(dummy_hcd_to_hcd(dum_hcd));
1131 	return 0;
1132 }
1133 
1134 static struct platform_driver dummy_udc_driver = {
1135 	.probe		= dummy_udc_probe,
1136 	.remove		= dummy_udc_remove,
1137 	.suspend	= dummy_udc_suspend,
1138 	.resume		= dummy_udc_resume,
1139 	.driver		= {
1140 		.name	= gadget_name,
1141 	},
1142 };
1143 
1144 /*-------------------------------------------------------------------------*/
1145 
1146 static unsigned int dummy_get_ep_idx(const struct usb_endpoint_descriptor *desc)
1147 {
1148 	unsigned int index;
1149 
1150 	index = usb_endpoint_num(desc) << 1;
1151 	if (usb_endpoint_dir_in(desc))
1152 		index |= 1;
1153 	return index;
1154 }
1155 
1156 /* HOST SIDE DRIVER
1157  *
1158  * this uses the hcd framework to hook up to host side drivers.
1159  * its root hub will only have one device, otherwise it acts like
1160  * a normal host controller.
1161  *
1162  * when urbs are queued, they're just stuck on a list that we
1163  * scan in a timer callback.  that callback connects writes from
1164  * the host with reads from the device, and so on, based on the
1165  * usb 2.0 rules.
1166  */
1167 
1168 static int dummy_ep_stream_en(struct dummy_hcd *dum_hcd, struct urb *urb)
1169 {
1170 	const struct usb_endpoint_descriptor *desc = &urb->ep->desc;
1171 	u32 index;
1172 
1173 	if (!usb_endpoint_xfer_bulk(desc))
1174 		return 0;
1175 
1176 	index = dummy_get_ep_idx(desc);
1177 	return (1 << index) & dum_hcd->stream_en_ep;
1178 }
1179 
1180 /*
1181  * The max stream number is saved as a nibble so for the 30 possible endpoints
1182  * we only 15 bytes of memory. Therefore we are limited to max 16 streams (0
1183  * means we use only 1 stream). The maximum according to the spec is 16bit so
1184  * if the 16 stream limit is about to go, the array size should be incremented
1185  * to 30 elements of type u16.
1186  */
1187 static int get_max_streams_for_pipe(struct dummy_hcd *dum_hcd,
1188 		unsigned int pipe)
1189 {
1190 	int max_streams;
1191 
1192 	max_streams = dum_hcd->num_stream[usb_pipeendpoint(pipe)];
1193 	if (usb_pipeout(pipe))
1194 		max_streams >>= 4;
1195 	else
1196 		max_streams &= 0xf;
1197 	max_streams++;
1198 	return max_streams;
1199 }
1200 
1201 static void set_max_streams_for_pipe(struct dummy_hcd *dum_hcd,
1202 		unsigned int pipe, unsigned int streams)
1203 {
1204 	int max_streams;
1205 
1206 	streams--;
1207 	max_streams = dum_hcd->num_stream[usb_pipeendpoint(pipe)];
1208 	if (usb_pipeout(pipe)) {
1209 		streams <<= 4;
1210 		max_streams &= 0xf;
1211 	} else {
1212 		max_streams &= 0xf0;
1213 	}
1214 	max_streams |= streams;
1215 	dum_hcd->num_stream[usb_pipeendpoint(pipe)] = max_streams;
1216 }
1217 
1218 static int dummy_validate_stream(struct dummy_hcd *dum_hcd, struct urb *urb)
1219 {
1220 	unsigned int max_streams;
1221 	int enabled;
1222 
1223 	enabled = dummy_ep_stream_en(dum_hcd, urb);
1224 	if (!urb->stream_id) {
1225 		if (enabled)
1226 			return -EINVAL;
1227 		return 0;
1228 	}
1229 	if (!enabled)
1230 		return -EINVAL;
1231 
1232 	max_streams = get_max_streams_for_pipe(dum_hcd,
1233 			usb_pipeendpoint(urb->pipe));
1234 	if (urb->stream_id > max_streams) {
1235 		dev_err(dummy_dev(dum_hcd), "Stream id %d is out of range.\n",
1236 				urb->stream_id);
1237 		BUG();
1238 		return -EINVAL;
1239 	}
1240 	return 0;
1241 }
1242 
1243 static int dummy_urb_enqueue(
1244 	struct usb_hcd			*hcd,
1245 	struct urb			*urb,
1246 	gfp_t				mem_flags
1247 ) {
1248 	struct dummy_hcd *dum_hcd;
1249 	struct urbp	*urbp;
1250 	unsigned long	flags;
1251 	int		rc;
1252 
1253 	urbp = kmalloc(sizeof *urbp, mem_flags);
1254 	if (!urbp)
1255 		return -ENOMEM;
1256 	urbp->urb = urb;
1257 	urbp->miter_started = 0;
1258 
1259 	dum_hcd = hcd_to_dummy_hcd(hcd);
1260 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
1261 
1262 	rc = dummy_validate_stream(dum_hcd, urb);
1263 	if (rc) {
1264 		kfree(urbp);
1265 		goto done;
1266 	}
1267 
1268 	rc = usb_hcd_link_urb_to_ep(hcd, urb);
1269 	if (rc) {
1270 		kfree(urbp);
1271 		goto done;
1272 	}
1273 
1274 	if (!dum_hcd->udev) {
1275 		dum_hcd->udev = urb->dev;
1276 		usb_get_dev(dum_hcd->udev);
1277 	} else if (unlikely(dum_hcd->udev != urb->dev))
1278 		dev_err(dummy_dev(dum_hcd), "usb_device address has changed!\n");
1279 
1280 	list_add_tail(&urbp->urbp_list, &dum_hcd->urbp_list);
1281 	urb->hcpriv = urbp;
1282 	if (!dum_hcd->next_frame_urbp)
1283 		dum_hcd->next_frame_urbp = urbp;
1284 	if (usb_pipetype(urb->pipe) == PIPE_CONTROL)
1285 		urb->error_count = 1;		/* mark as a new urb */
1286 
1287 	/* kick the scheduler, it'll do the rest */
1288 	if (!timer_pending(&dum_hcd->timer))
1289 		mod_timer(&dum_hcd->timer, jiffies + 1);
1290 
1291  done:
1292 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
1293 	return rc;
1294 }
1295 
1296 static int dummy_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
1297 {
1298 	struct dummy_hcd *dum_hcd;
1299 	unsigned long	flags;
1300 	int		rc;
1301 
1302 	/* giveback happens automatically in timer callback,
1303 	 * so make sure the callback happens */
1304 	dum_hcd = hcd_to_dummy_hcd(hcd);
1305 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
1306 
1307 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
1308 	if (!rc && dum_hcd->rh_state != DUMMY_RH_RUNNING &&
1309 			!list_empty(&dum_hcd->urbp_list))
1310 		mod_timer(&dum_hcd->timer, jiffies);
1311 
1312 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
1313 	return rc;
1314 }
1315 
1316 static int dummy_perform_transfer(struct urb *urb, struct dummy_request *req,
1317 		u32 len)
1318 {
1319 	void *ubuf, *rbuf;
1320 	struct urbp *urbp = urb->hcpriv;
1321 	int to_host;
1322 	struct sg_mapping_iter *miter = &urbp->miter;
1323 	u32 trans = 0;
1324 	u32 this_sg;
1325 	bool next_sg;
1326 
1327 	to_host = usb_urb_dir_in(urb);
1328 	rbuf = req->req.buf + req->req.actual;
1329 
1330 	if (!urb->num_sgs) {
1331 		ubuf = urb->transfer_buffer + urb->actual_length;
1332 		if (to_host)
1333 			memcpy(ubuf, rbuf, len);
1334 		else
1335 			memcpy(rbuf, ubuf, len);
1336 		return len;
1337 	}
1338 
1339 	if (!urbp->miter_started) {
1340 		u32 flags = SG_MITER_ATOMIC;
1341 
1342 		if (to_host)
1343 			flags |= SG_MITER_TO_SG;
1344 		else
1345 			flags |= SG_MITER_FROM_SG;
1346 
1347 		sg_miter_start(miter, urb->sg, urb->num_sgs, flags);
1348 		urbp->miter_started = 1;
1349 	}
1350 	next_sg = sg_miter_next(miter);
1351 	if (next_sg == false) {
1352 		WARN_ON_ONCE(1);
1353 		return -EINVAL;
1354 	}
1355 	do {
1356 		ubuf = miter->addr;
1357 		this_sg = min_t(u32, len, miter->length);
1358 		miter->consumed = this_sg;
1359 		trans += this_sg;
1360 
1361 		if (to_host)
1362 			memcpy(ubuf, rbuf, this_sg);
1363 		else
1364 			memcpy(rbuf, ubuf, this_sg);
1365 		len -= this_sg;
1366 
1367 		if (!len)
1368 			break;
1369 		next_sg = sg_miter_next(miter);
1370 		if (next_sg == false) {
1371 			WARN_ON_ONCE(1);
1372 			return -EINVAL;
1373 		}
1374 
1375 		rbuf += this_sg;
1376 	} while (1);
1377 
1378 	sg_miter_stop(miter);
1379 	return trans;
1380 }
1381 
1382 /* transfer up to a frame's worth; caller must own lock */
1383 static int transfer(struct dummy_hcd *dum_hcd, struct urb *urb,
1384 		struct dummy_ep *ep, int limit, int *status)
1385 {
1386 	struct dummy		*dum = dum_hcd->dum;
1387 	struct dummy_request	*req;
1388 	int			sent = 0;
1389 
1390 top:
1391 	/* if there's no request queued, the device is NAKing; return */
1392 	list_for_each_entry(req, &ep->queue, queue) {
1393 		unsigned	host_len, dev_len, len;
1394 		int		is_short, to_host;
1395 		int		rescan = 0;
1396 
1397 		if (dummy_ep_stream_en(dum_hcd, urb)) {
1398 			if ((urb->stream_id != req->req.stream_id))
1399 				continue;
1400 		}
1401 
1402 		/* 1..N packets of ep->ep.maxpacket each ... the last one
1403 		 * may be short (including zero length).
1404 		 *
1405 		 * writer can send a zlp explicitly (length 0) or implicitly
1406 		 * (length mod maxpacket zero, and 'zero' flag); they always
1407 		 * terminate reads.
1408 		 */
1409 		host_len = urb->transfer_buffer_length - urb->actual_length;
1410 		dev_len = req->req.length - req->req.actual;
1411 		len = min(host_len, dev_len);
1412 
1413 		/* FIXME update emulated data toggle too */
1414 
1415 		to_host = usb_urb_dir_in(urb);
1416 		if (unlikely(len == 0))
1417 			is_short = 1;
1418 		else {
1419 			/* not enough bandwidth left? */
1420 			if (limit < ep->ep.maxpacket && limit < len)
1421 				break;
1422 			len = min_t(unsigned, len, limit);
1423 			if (len == 0)
1424 				break;
1425 
1426 			/* send multiple of maxpacket first, then remainder */
1427 			if (len >= ep->ep.maxpacket) {
1428 				is_short = 0;
1429 				if (len % ep->ep.maxpacket)
1430 					rescan = 1;
1431 				len -= len % ep->ep.maxpacket;
1432 			} else {
1433 				is_short = 1;
1434 			}
1435 
1436 			len = dummy_perform_transfer(urb, req, len);
1437 
1438 			ep->last_io = jiffies;
1439 			if ((int)len < 0) {
1440 				req->req.status = len;
1441 			} else {
1442 				limit -= len;
1443 				sent += len;
1444 				urb->actual_length += len;
1445 				req->req.actual += len;
1446 			}
1447 		}
1448 
1449 		/* short packets terminate, maybe with overflow/underflow.
1450 		 * it's only really an error to write too much.
1451 		 *
1452 		 * partially filling a buffer optionally blocks queue advances
1453 		 * (so completion handlers can clean up the queue) but we don't
1454 		 * need to emulate such data-in-flight.
1455 		 */
1456 		if (is_short) {
1457 			if (host_len == dev_len) {
1458 				req->req.status = 0;
1459 				*status = 0;
1460 			} else if (to_host) {
1461 				req->req.status = 0;
1462 				if (dev_len > host_len)
1463 					*status = -EOVERFLOW;
1464 				else
1465 					*status = 0;
1466 			} else {
1467 				*status = 0;
1468 				if (host_len > dev_len)
1469 					req->req.status = -EOVERFLOW;
1470 				else
1471 					req->req.status = 0;
1472 			}
1473 
1474 		/*
1475 		 * many requests terminate without a short packet.
1476 		 * send a zlp if demanded by flags.
1477 		 */
1478 		} else {
1479 			if (req->req.length == req->req.actual) {
1480 				if (req->req.zero && to_host)
1481 					rescan = 1;
1482 				else
1483 					req->req.status = 0;
1484 			}
1485 			if (urb->transfer_buffer_length == urb->actual_length) {
1486 				if (urb->transfer_flags & URB_ZERO_PACKET &&
1487 				    !to_host)
1488 					rescan = 1;
1489 				else
1490 					*status = 0;
1491 			}
1492 		}
1493 
1494 		/* device side completion --> continuable */
1495 		if (req->req.status != -EINPROGRESS) {
1496 			list_del_init(&req->queue);
1497 
1498 			spin_unlock(&dum->lock);
1499 			usb_gadget_giveback_request(&ep->ep, &req->req);
1500 			spin_lock(&dum->lock);
1501 
1502 			/* requests might have been unlinked... */
1503 			rescan = 1;
1504 		}
1505 
1506 		/* host side completion --> terminate */
1507 		if (*status != -EINPROGRESS)
1508 			break;
1509 
1510 		/* rescan to continue with any other queued i/o */
1511 		if (rescan)
1512 			goto top;
1513 	}
1514 	return sent;
1515 }
1516 
1517 static int periodic_bytes(struct dummy *dum, struct dummy_ep *ep)
1518 {
1519 	int	limit = ep->ep.maxpacket;
1520 
1521 	if (dum->gadget.speed == USB_SPEED_HIGH) {
1522 		int	tmp;
1523 
1524 		/* high bandwidth mode */
1525 		tmp = usb_endpoint_maxp_mult(ep->desc);
1526 		tmp *= 8 /* applies to entire frame */;
1527 		limit += limit * tmp;
1528 	}
1529 	if (dum->gadget.speed == USB_SPEED_SUPER) {
1530 		switch (usb_endpoint_type(ep->desc)) {
1531 		case USB_ENDPOINT_XFER_ISOC:
1532 			/* Sec. 4.4.8.2 USB3.0 Spec */
1533 			limit = 3 * 16 * 1024 * 8;
1534 			break;
1535 		case USB_ENDPOINT_XFER_INT:
1536 			/* Sec. 4.4.7.2 USB3.0 Spec */
1537 			limit = 3 * 1024 * 8;
1538 			break;
1539 		case USB_ENDPOINT_XFER_BULK:
1540 		default:
1541 			break;
1542 		}
1543 	}
1544 	return limit;
1545 }
1546 
1547 #define is_active(dum_hcd)	((dum_hcd->port_status & \
1548 		(USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE | \
1549 			USB_PORT_STAT_SUSPEND)) \
1550 		== (USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE))
1551 
1552 static struct dummy_ep *find_endpoint(struct dummy *dum, u8 address)
1553 {
1554 	int		i;
1555 
1556 	if (!is_active((dum->gadget.speed == USB_SPEED_SUPER ?
1557 			dum->ss_hcd : dum->hs_hcd)))
1558 		return NULL;
1559 	if (!dum->ints_enabled)
1560 		return NULL;
1561 	if ((address & ~USB_DIR_IN) == 0)
1562 		return &dum->ep[0];
1563 	for (i = 1; i < DUMMY_ENDPOINTS; i++) {
1564 		struct dummy_ep	*ep = &dum->ep[i];
1565 
1566 		if (!ep->desc)
1567 			continue;
1568 		if (ep->desc->bEndpointAddress == address)
1569 			return ep;
1570 	}
1571 	return NULL;
1572 }
1573 
1574 #undef is_active
1575 
1576 #define Dev_Request	(USB_TYPE_STANDARD | USB_RECIP_DEVICE)
1577 #define Dev_InRequest	(Dev_Request | USB_DIR_IN)
1578 #define Intf_Request	(USB_TYPE_STANDARD | USB_RECIP_INTERFACE)
1579 #define Intf_InRequest	(Intf_Request | USB_DIR_IN)
1580 #define Ep_Request	(USB_TYPE_STANDARD | USB_RECIP_ENDPOINT)
1581 #define Ep_InRequest	(Ep_Request | USB_DIR_IN)
1582 
1583 
1584 /**
1585  * handle_control_request() - handles all control transfers
1586  * @dum_hcd: pointer to dummy (the_controller)
1587  * @urb: the urb request to handle
1588  * @setup: pointer to the setup data for a USB device control
1589  *	 request
1590  * @status: pointer to request handling status
1591  *
1592  * Return 0 - if the request was handled
1593  *	  1 - if the request wasn't handles
1594  *	  error code on error
1595  */
1596 static int handle_control_request(struct dummy_hcd *dum_hcd, struct urb *urb,
1597 				  struct usb_ctrlrequest *setup,
1598 				  int *status)
1599 {
1600 	struct dummy_ep		*ep2;
1601 	struct dummy		*dum = dum_hcd->dum;
1602 	int			ret_val = 1;
1603 	unsigned	w_index;
1604 	unsigned	w_value;
1605 
1606 	w_index = le16_to_cpu(setup->wIndex);
1607 	w_value = le16_to_cpu(setup->wValue);
1608 	switch (setup->bRequest) {
1609 	case USB_REQ_SET_ADDRESS:
1610 		if (setup->bRequestType != Dev_Request)
1611 			break;
1612 		dum->address = w_value;
1613 		*status = 0;
1614 		dev_dbg(udc_dev(dum), "set_address = %d\n",
1615 				w_value);
1616 		ret_val = 0;
1617 		break;
1618 	case USB_REQ_SET_FEATURE:
1619 		if (setup->bRequestType == Dev_Request) {
1620 			ret_val = 0;
1621 			switch (w_value) {
1622 			case USB_DEVICE_REMOTE_WAKEUP:
1623 				break;
1624 			case USB_DEVICE_B_HNP_ENABLE:
1625 				dum->gadget.b_hnp_enable = 1;
1626 				break;
1627 			case USB_DEVICE_A_HNP_SUPPORT:
1628 				dum->gadget.a_hnp_support = 1;
1629 				break;
1630 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1631 				dum->gadget.a_alt_hnp_support = 1;
1632 				break;
1633 			case USB_DEVICE_U1_ENABLE:
1634 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1635 				    HCD_USB3)
1636 					w_value = USB_DEV_STAT_U1_ENABLED;
1637 				else
1638 					ret_val = -EOPNOTSUPP;
1639 				break;
1640 			case USB_DEVICE_U2_ENABLE:
1641 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1642 				    HCD_USB3)
1643 					w_value = USB_DEV_STAT_U2_ENABLED;
1644 				else
1645 					ret_val = -EOPNOTSUPP;
1646 				break;
1647 			case USB_DEVICE_LTM_ENABLE:
1648 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1649 				    HCD_USB3)
1650 					w_value = USB_DEV_STAT_LTM_ENABLED;
1651 				else
1652 					ret_val = -EOPNOTSUPP;
1653 				break;
1654 			default:
1655 				ret_val = -EOPNOTSUPP;
1656 			}
1657 			if (ret_val == 0) {
1658 				dum->devstatus |= (1 << w_value);
1659 				*status = 0;
1660 			}
1661 		} else if (setup->bRequestType == Ep_Request) {
1662 			/* endpoint halt */
1663 			ep2 = find_endpoint(dum, w_index);
1664 			if (!ep2 || ep2->ep.name == ep0name) {
1665 				ret_val = -EOPNOTSUPP;
1666 				break;
1667 			}
1668 			ep2->halted = 1;
1669 			ret_val = 0;
1670 			*status = 0;
1671 		}
1672 		break;
1673 	case USB_REQ_CLEAR_FEATURE:
1674 		if (setup->bRequestType == Dev_Request) {
1675 			ret_val = 0;
1676 			switch (w_value) {
1677 			case USB_DEVICE_REMOTE_WAKEUP:
1678 				w_value = USB_DEVICE_REMOTE_WAKEUP;
1679 				break;
1680 			case USB_DEVICE_U1_ENABLE:
1681 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1682 				    HCD_USB3)
1683 					w_value = USB_DEV_STAT_U1_ENABLED;
1684 				else
1685 					ret_val = -EOPNOTSUPP;
1686 				break;
1687 			case USB_DEVICE_U2_ENABLE:
1688 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1689 				    HCD_USB3)
1690 					w_value = USB_DEV_STAT_U2_ENABLED;
1691 				else
1692 					ret_val = -EOPNOTSUPP;
1693 				break;
1694 			case USB_DEVICE_LTM_ENABLE:
1695 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1696 				    HCD_USB3)
1697 					w_value = USB_DEV_STAT_LTM_ENABLED;
1698 				else
1699 					ret_val = -EOPNOTSUPP;
1700 				break;
1701 			default:
1702 				ret_val = -EOPNOTSUPP;
1703 				break;
1704 			}
1705 			if (ret_val == 0) {
1706 				dum->devstatus &= ~(1 << w_value);
1707 				*status = 0;
1708 			}
1709 		} else if (setup->bRequestType == Ep_Request) {
1710 			/* endpoint halt */
1711 			ep2 = find_endpoint(dum, w_index);
1712 			if (!ep2) {
1713 				ret_val = -EOPNOTSUPP;
1714 				break;
1715 			}
1716 			if (!ep2->wedged)
1717 				ep2->halted = 0;
1718 			ret_val = 0;
1719 			*status = 0;
1720 		}
1721 		break;
1722 	case USB_REQ_GET_STATUS:
1723 		if (setup->bRequestType == Dev_InRequest
1724 				|| setup->bRequestType == Intf_InRequest
1725 				|| setup->bRequestType == Ep_InRequest) {
1726 			char *buf;
1727 			/*
1728 			 * device: remote wakeup, selfpowered
1729 			 * interface: nothing
1730 			 * endpoint: halt
1731 			 */
1732 			buf = (char *)urb->transfer_buffer;
1733 			if (urb->transfer_buffer_length > 0) {
1734 				if (setup->bRequestType == Ep_InRequest) {
1735 					ep2 = find_endpoint(dum, w_index);
1736 					if (!ep2) {
1737 						ret_val = -EOPNOTSUPP;
1738 						break;
1739 					}
1740 					buf[0] = ep2->halted;
1741 				} else if (setup->bRequestType ==
1742 					   Dev_InRequest) {
1743 					buf[0] = (u8)dum->devstatus;
1744 				} else
1745 					buf[0] = 0;
1746 			}
1747 			if (urb->transfer_buffer_length > 1)
1748 				buf[1] = 0;
1749 			urb->actual_length = min_t(u32, 2,
1750 				urb->transfer_buffer_length);
1751 			ret_val = 0;
1752 			*status = 0;
1753 		}
1754 		break;
1755 	}
1756 	return ret_val;
1757 }
1758 
1759 /*
1760  * Drive both sides of the transfers; looks like irq handlers to both
1761  * drivers except that the callbacks are invoked from soft interrupt
1762  * context.
1763  */
1764 static void dummy_timer(struct timer_list *t)
1765 {
1766 	struct dummy_hcd	*dum_hcd = from_timer(dum_hcd, t, timer);
1767 	struct dummy		*dum = dum_hcd->dum;
1768 	struct urbp		*urbp, *tmp;
1769 	unsigned long		flags;
1770 	int			limit, total;
1771 	int			i;
1772 
1773 	/* simplistic model for one frame's bandwidth */
1774 	/* FIXME: account for transaction and packet overhead */
1775 	switch (dum->gadget.speed) {
1776 	case USB_SPEED_LOW:
1777 		total = 8/*bytes*/ * 12/*packets*/;
1778 		break;
1779 	case USB_SPEED_FULL:
1780 		total = 64/*bytes*/ * 19/*packets*/;
1781 		break;
1782 	case USB_SPEED_HIGH:
1783 		total = 512/*bytes*/ * 13/*packets*/ * 8/*uframes*/;
1784 		break;
1785 	case USB_SPEED_SUPER:
1786 		/* Bus speed is 500000 bytes/ms, so use a little less */
1787 		total = 490000;
1788 		break;
1789 	default:	/* Can't happen */
1790 		dev_err(dummy_dev(dum_hcd), "bogus device speed\n");
1791 		total = 0;
1792 		break;
1793 	}
1794 
1795 	/* FIXME if HZ != 1000 this will probably misbehave ... */
1796 
1797 	/* look at each urb queued by the host side driver */
1798 	spin_lock_irqsave(&dum->lock, flags);
1799 
1800 	if (!dum_hcd->udev) {
1801 		dev_err(dummy_dev(dum_hcd),
1802 				"timer fired with no URBs pending?\n");
1803 		spin_unlock_irqrestore(&dum->lock, flags);
1804 		return;
1805 	}
1806 	dum_hcd->next_frame_urbp = NULL;
1807 
1808 	for (i = 0; i < DUMMY_ENDPOINTS; i++) {
1809 		if (!ep_info[i].name)
1810 			break;
1811 		dum->ep[i].already_seen = 0;
1812 	}
1813 
1814 restart:
1815 	list_for_each_entry_safe(urbp, tmp, &dum_hcd->urbp_list, urbp_list) {
1816 		struct urb		*urb;
1817 		struct dummy_request	*req;
1818 		u8			address;
1819 		struct dummy_ep		*ep = NULL;
1820 		int			status = -EINPROGRESS;
1821 
1822 		/* stop when we reach URBs queued after the timer interrupt */
1823 		if (urbp == dum_hcd->next_frame_urbp)
1824 			break;
1825 
1826 		urb = urbp->urb;
1827 		if (urb->unlinked)
1828 			goto return_urb;
1829 		else if (dum_hcd->rh_state != DUMMY_RH_RUNNING)
1830 			continue;
1831 
1832 		/* Used up this frame's bandwidth? */
1833 		if (total <= 0)
1834 			continue;
1835 
1836 		/* find the gadget's ep for this request (if configured) */
1837 		address = usb_pipeendpoint (urb->pipe);
1838 		if (usb_urb_dir_in(urb))
1839 			address |= USB_DIR_IN;
1840 		ep = find_endpoint(dum, address);
1841 		if (!ep) {
1842 			/* set_configuration() disagreement */
1843 			dev_dbg(dummy_dev(dum_hcd),
1844 				"no ep configured for urb %p\n",
1845 				urb);
1846 			status = -EPROTO;
1847 			goto return_urb;
1848 		}
1849 
1850 		if (ep->already_seen)
1851 			continue;
1852 		ep->already_seen = 1;
1853 		if (ep == &dum->ep[0] && urb->error_count) {
1854 			ep->setup_stage = 1;	/* a new urb */
1855 			urb->error_count = 0;
1856 		}
1857 		if (ep->halted && !ep->setup_stage) {
1858 			/* NOTE: must not be iso! */
1859 			dev_dbg(dummy_dev(dum_hcd), "ep %s halted, urb %p\n",
1860 					ep->ep.name, urb);
1861 			status = -EPIPE;
1862 			goto return_urb;
1863 		}
1864 		/* FIXME make sure both ends agree on maxpacket */
1865 
1866 		/* handle control requests */
1867 		if (ep == &dum->ep[0] && ep->setup_stage) {
1868 			struct usb_ctrlrequest		setup;
1869 			int				value = 1;
1870 
1871 			setup = *(struct usb_ctrlrequest *) urb->setup_packet;
1872 			/* paranoia, in case of stale queued data */
1873 			list_for_each_entry(req, &ep->queue, queue) {
1874 				list_del_init(&req->queue);
1875 				req->req.status = -EOVERFLOW;
1876 				dev_dbg(udc_dev(dum), "stale req = %p\n",
1877 						req);
1878 
1879 				spin_unlock(&dum->lock);
1880 				usb_gadget_giveback_request(&ep->ep, &req->req);
1881 				spin_lock(&dum->lock);
1882 				ep->already_seen = 0;
1883 				goto restart;
1884 			}
1885 
1886 			/* gadget driver never sees set_address or operations
1887 			 * on standard feature flags.  some hardware doesn't
1888 			 * even expose them.
1889 			 */
1890 			ep->last_io = jiffies;
1891 			ep->setup_stage = 0;
1892 			ep->halted = 0;
1893 
1894 			value = handle_control_request(dum_hcd, urb, &setup,
1895 						       &status);
1896 
1897 			/* gadget driver handles all other requests.  block
1898 			 * until setup() returns; no reentrancy issues etc.
1899 			 */
1900 			if (value > 0) {
1901 				++dum->callback_usage;
1902 				spin_unlock(&dum->lock);
1903 				value = dum->driver->setup(&dum->gadget,
1904 						&setup);
1905 				spin_lock(&dum->lock);
1906 				--dum->callback_usage;
1907 
1908 				if (value >= 0) {
1909 					/* no delays (max 64KB data stage) */
1910 					limit = 64*1024;
1911 					goto treat_control_like_bulk;
1912 				}
1913 				/* error, see below */
1914 			}
1915 
1916 			if (value < 0) {
1917 				if (value != -EOPNOTSUPP)
1918 					dev_dbg(udc_dev(dum),
1919 						"setup --> %d\n",
1920 						value);
1921 				status = -EPIPE;
1922 				urb->actual_length = 0;
1923 			}
1924 
1925 			goto return_urb;
1926 		}
1927 
1928 		/* non-control requests */
1929 		limit = total;
1930 		switch (usb_pipetype(urb->pipe)) {
1931 		case PIPE_ISOCHRONOUS:
1932 			/*
1933 			 * We don't support isochronous.  But if we did,
1934 			 * here are some of the issues we'd have to face:
1935 			 *
1936 			 * Is it urb->interval since the last xfer?
1937 			 * Use urb->iso_frame_desc[i].
1938 			 * Complete whether or not ep has requests queued.
1939 			 * Report random errors, to debug drivers.
1940 			 */
1941 			limit = max(limit, periodic_bytes(dum, ep));
1942 			status = -EINVAL;	/* fail all xfers */
1943 			break;
1944 
1945 		case PIPE_INTERRUPT:
1946 			/* FIXME is it urb->interval since the last xfer?
1947 			 * this almost certainly polls too fast.
1948 			 */
1949 			limit = max(limit, periodic_bytes(dum, ep));
1950 			fallthrough;
1951 
1952 		default:
1953 treat_control_like_bulk:
1954 			ep->last_io = jiffies;
1955 			total -= transfer(dum_hcd, urb, ep, limit, &status);
1956 			break;
1957 		}
1958 
1959 		/* incomplete transfer? */
1960 		if (status == -EINPROGRESS)
1961 			continue;
1962 
1963 return_urb:
1964 		list_del(&urbp->urbp_list);
1965 		kfree(urbp);
1966 		if (ep)
1967 			ep->already_seen = ep->setup_stage = 0;
1968 
1969 		usb_hcd_unlink_urb_from_ep(dummy_hcd_to_hcd(dum_hcd), urb);
1970 		spin_unlock(&dum->lock);
1971 		usb_hcd_giveback_urb(dummy_hcd_to_hcd(dum_hcd), urb, status);
1972 		spin_lock(&dum->lock);
1973 
1974 		goto restart;
1975 	}
1976 
1977 	if (list_empty(&dum_hcd->urbp_list)) {
1978 		usb_put_dev(dum_hcd->udev);
1979 		dum_hcd->udev = NULL;
1980 	} else if (dum_hcd->rh_state == DUMMY_RH_RUNNING) {
1981 		/* want a 1 msec delay here */
1982 		mod_timer(&dum_hcd->timer, jiffies + msecs_to_jiffies(1));
1983 	}
1984 
1985 	spin_unlock_irqrestore(&dum->lock, flags);
1986 }
1987 
1988 /*-------------------------------------------------------------------------*/
1989 
1990 #define PORT_C_MASK \
1991 	((USB_PORT_STAT_C_CONNECTION \
1992 	| USB_PORT_STAT_C_ENABLE \
1993 	| USB_PORT_STAT_C_SUSPEND \
1994 	| USB_PORT_STAT_C_OVERCURRENT \
1995 	| USB_PORT_STAT_C_RESET) << 16)
1996 
1997 static int dummy_hub_status(struct usb_hcd *hcd, char *buf)
1998 {
1999 	struct dummy_hcd	*dum_hcd;
2000 	unsigned long		flags;
2001 	int			retval = 0;
2002 
2003 	dum_hcd = hcd_to_dummy_hcd(hcd);
2004 
2005 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2006 	if (!HCD_HW_ACCESSIBLE(hcd))
2007 		goto done;
2008 
2009 	if (dum_hcd->resuming && time_after_eq(jiffies, dum_hcd->re_timeout)) {
2010 		dum_hcd->port_status |= (USB_PORT_STAT_C_SUSPEND << 16);
2011 		dum_hcd->port_status &= ~USB_PORT_STAT_SUSPEND;
2012 		set_link_state(dum_hcd);
2013 	}
2014 
2015 	if ((dum_hcd->port_status & PORT_C_MASK) != 0) {
2016 		*buf = (1 << 1);
2017 		dev_dbg(dummy_dev(dum_hcd), "port status 0x%08x has changes\n",
2018 				dum_hcd->port_status);
2019 		retval = 1;
2020 		if (dum_hcd->rh_state == DUMMY_RH_SUSPENDED)
2021 			usb_hcd_resume_root_hub(hcd);
2022 	}
2023 done:
2024 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2025 	return retval;
2026 }
2027 
2028 /* usb 3.0 root hub device descriptor */
2029 static struct {
2030 	struct usb_bos_descriptor bos;
2031 	struct usb_ss_cap_descriptor ss_cap;
2032 } __packed usb3_bos_desc = {
2033 
2034 	.bos = {
2035 		.bLength		= USB_DT_BOS_SIZE,
2036 		.bDescriptorType	= USB_DT_BOS,
2037 		.wTotalLength		= cpu_to_le16(sizeof(usb3_bos_desc)),
2038 		.bNumDeviceCaps		= 1,
2039 	},
2040 	.ss_cap = {
2041 		.bLength		= USB_DT_USB_SS_CAP_SIZE,
2042 		.bDescriptorType	= USB_DT_DEVICE_CAPABILITY,
2043 		.bDevCapabilityType	= USB_SS_CAP_TYPE,
2044 		.wSpeedSupported	= cpu_to_le16(USB_5GBPS_OPERATION),
2045 		.bFunctionalitySupport	= ilog2(USB_5GBPS_OPERATION),
2046 	},
2047 };
2048 
2049 static inline void
2050 ss_hub_descriptor(struct usb_hub_descriptor *desc)
2051 {
2052 	memset(desc, 0, sizeof *desc);
2053 	desc->bDescriptorType = USB_DT_SS_HUB;
2054 	desc->bDescLength = 12;
2055 	desc->wHubCharacteristics = cpu_to_le16(
2056 			HUB_CHAR_INDV_PORT_LPSM |
2057 			HUB_CHAR_COMMON_OCPM);
2058 	desc->bNbrPorts = 1;
2059 	desc->u.ss.bHubHdrDecLat = 0x04; /* Worst case: 0.4 micro sec*/
2060 	desc->u.ss.DeviceRemovable = 0;
2061 }
2062 
2063 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
2064 {
2065 	memset(desc, 0, sizeof *desc);
2066 	desc->bDescriptorType = USB_DT_HUB;
2067 	desc->bDescLength = 9;
2068 	desc->wHubCharacteristics = cpu_to_le16(
2069 			HUB_CHAR_INDV_PORT_LPSM |
2070 			HUB_CHAR_COMMON_OCPM);
2071 	desc->bNbrPorts = 1;
2072 	desc->u.hs.DeviceRemovable[0] = 0;
2073 	desc->u.hs.DeviceRemovable[1] = 0xff;	/* PortPwrCtrlMask */
2074 }
2075 
2076 static int dummy_hub_control(
2077 	struct usb_hcd	*hcd,
2078 	u16		typeReq,
2079 	u16		wValue,
2080 	u16		wIndex,
2081 	char		*buf,
2082 	u16		wLength
2083 ) {
2084 	struct dummy_hcd *dum_hcd;
2085 	int		retval = 0;
2086 	unsigned long	flags;
2087 
2088 	if (!HCD_HW_ACCESSIBLE(hcd))
2089 		return -ETIMEDOUT;
2090 
2091 	dum_hcd = hcd_to_dummy_hcd(hcd);
2092 
2093 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2094 	switch (typeReq) {
2095 	case ClearHubFeature:
2096 		break;
2097 	case ClearPortFeature:
2098 		switch (wValue) {
2099 		case USB_PORT_FEAT_SUSPEND:
2100 			if (hcd->speed == HCD_USB3) {
2101 				dev_dbg(dummy_dev(dum_hcd),
2102 					 "USB_PORT_FEAT_SUSPEND req not "
2103 					 "supported for USB 3.0 roothub\n");
2104 				goto error;
2105 			}
2106 			if (dum_hcd->port_status & USB_PORT_STAT_SUSPEND) {
2107 				/* 20msec resume signaling */
2108 				dum_hcd->resuming = 1;
2109 				dum_hcd->re_timeout = jiffies +
2110 						msecs_to_jiffies(20);
2111 			}
2112 			break;
2113 		case USB_PORT_FEAT_POWER:
2114 			dev_dbg(dummy_dev(dum_hcd), "power-off\n");
2115 			if (hcd->speed == HCD_USB3)
2116 				dum_hcd->port_status &= ~USB_SS_PORT_STAT_POWER;
2117 			else
2118 				dum_hcd->port_status &= ~USB_PORT_STAT_POWER;
2119 			set_link_state(dum_hcd);
2120 			break;
2121 		case USB_PORT_FEAT_ENABLE:
2122 		case USB_PORT_FEAT_C_ENABLE:
2123 		case USB_PORT_FEAT_C_SUSPEND:
2124 			/* Not allowed for USB-3 */
2125 			if (hcd->speed == HCD_USB3)
2126 				goto error;
2127 			fallthrough;
2128 		case USB_PORT_FEAT_C_CONNECTION:
2129 		case USB_PORT_FEAT_C_RESET:
2130 			dum_hcd->port_status &= ~(1 << wValue);
2131 			set_link_state(dum_hcd);
2132 			break;
2133 		default:
2134 		/* Disallow INDICATOR and C_OVER_CURRENT */
2135 			goto error;
2136 		}
2137 		break;
2138 	case GetHubDescriptor:
2139 		if (hcd->speed == HCD_USB3 &&
2140 				(wLength < USB_DT_SS_HUB_SIZE ||
2141 				 wValue != (USB_DT_SS_HUB << 8))) {
2142 			dev_dbg(dummy_dev(dum_hcd),
2143 				"Wrong hub descriptor type for "
2144 				"USB 3.0 roothub.\n");
2145 			goto error;
2146 		}
2147 		if (hcd->speed == HCD_USB3)
2148 			ss_hub_descriptor((struct usb_hub_descriptor *) buf);
2149 		else
2150 			hub_descriptor((struct usb_hub_descriptor *) buf);
2151 		break;
2152 
2153 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
2154 		if (hcd->speed != HCD_USB3)
2155 			goto error;
2156 
2157 		if ((wValue >> 8) != USB_DT_BOS)
2158 			goto error;
2159 
2160 		memcpy(buf, &usb3_bos_desc, sizeof(usb3_bos_desc));
2161 		retval = sizeof(usb3_bos_desc);
2162 		break;
2163 
2164 	case GetHubStatus:
2165 		*(__le32 *) buf = cpu_to_le32(0);
2166 		break;
2167 	case GetPortStatus:
2168 		if (wIndex != 1)
2169 			retval = -EPIPE;
2170 
2171 		/* whoever resets or resumes must GetPortStatus to
2172 		 * complete it!!
2173 		 */
2174 		if (dum_hcd->resuming &&
2175 				time_after_eq(jiffies, dum_hcd->re_timeout)) {
2176 			dum_hcd->port_status |= (USB_PORT_STAT_C_SUSPEND << 16);
2177 			dum_hcd->port_status &= ~USB_PORT_STAT_SUSPEND;
2178 		}
2179 		if ((dum_hcd->port_status & USB_PORT_STAT_RESET) != 0 &&
2180 				time_after_eq(jiffies, dum_hcd->re_timeout)) {
2181 			dum_hcd->port_status |= (USB_PORT_STAT_C_RESET << 16);
2182 			dum_hcd->port_status &= ~USB_PORT_STAT_RESET;
2183 			if (dum_hcd->dum->pullup) {
2184 				dum_hcd->port_status |= USB_PORT_STAT_ENABLE;
2185 
2186 				if (hcd->speed < HCD_USB3) {
2187 					switch (dum_hcd->dum->gadget.speed) {
2188 					case USB_SPEED_HIGH:
2189 						dum_hcd->port_status |=
2190 						      USB_PORT_STAT_HIGH_SPEED;
2191 						break;
2192 					case USB_SPEED_LOW:
2193 						dum_hcd->dum->gadget.ep0->
2194 							maxpacket = 8;
2195 						dum_hcd->port_status |=
2196 							USB_PORT_STAT_LOW_SPEED;
2197 						break;
2198 					default:
2199 						break;
2200 					}
2201 				}
2202 			}
2203 		}
2204 		set_link_state(dum_hcd);
2205 		((__le16 *) buf)[0] = cpu_to_le16(dum_hcd->port_status);
2206 		((__le16 *) buf)[1] = cpu_to_le16(dum_hcd->port_status >> 16);
2207 		break;
2208 	case SetHubFeature:
2209 		retval = -EPIPE;
2210 		break;
2211 	case SetPortFeature:
2212 		switch (wValue) {
2213 		case USB_PORT_FEAT_LINK_STATE:
2214 			if (hcd->speed != HCD_USB3) {
2215 				dev_dbg(dummy_dev(dum_hcd),
2216 					 "USB_PORT_FEAT_LINK_STATE req not "
2217 					 "supported for USB 2.0 roothub\n");
2218 				goto error;
2219 			}
2220 			/*
2221 			 * Since this is dummy we don't have an actual link so
2222 			 * there is nothing to do for the SET_LINK_STATE cmd
2223 			 */
2224 			break;
2225 		case USB_PORT_FEAT_U1_TIMEOUT:
2226 		case USB_PORT_FEAT_U2_TIMEOUT:
2227 			/* TODO: add suspend/resume support! */
2228 			if (hcd->speed != HCD_USB3) {
2229 				dev_dbg(dummy_dev(dum_hcd),
2230 					 "USB_PORT_FEAT_U1/2_TIMEOUT req not "
2231 					 "supported for USB 2.0 roothub\n");
2232 				goto error;
2233 			}
2234 			break;
2235 		case USB_PORT_FEAT_SUSPEND:
2236 			/* Applicable only for USB2.0 hub */
2237 			if (hcd->speed == HCD_USB3) {
2238 				dev_dbg(dummy_dev(dum_hcd),
2239 					 "USB_PORT_FEAT_SUSPEND req not "
2240 					 "supported for USB 3.0 roothub\n");
2241 				goto error;
2242 			}
2243 			if (dum_hcd->active) {
2244 				dum_hcd->port_status |= USB_PORT_STAT_SUSPEND;
2245 
2246 				/* HNP would happen here; for now we
2247 				 * assume b_bus_req is always true.
2248 				 */
2249 				set_link_state(dum_hcd);
2250 				if (((1 << USB_DEVICE_B_HNP_ENABLE)
2251 						& dum_hcd->dum->devstatus) != 0)
2252 					dev_dbg(dummy_dev(dum_hcd),
2253 							"no HNP yet!\n");
2254 			}
2255 			break;
2256 		case USB_PORT_FEAT_POWER:
2257 			if (hcd->speed == HCD_USB3)
2258 				dum_hcd->port_status |= USB_SS_PORT_STAT_POWER;
2259 			else
2260 				dum_hcd->port_status |= USB_PORT_STAT_POWER;
2261 			set_link_state(dum_hcd);
2262 			break;
2263 		case USB_PORT_FEAT_BH_PORT_RESET:
2264 			/* Applicable only for USB3.0 hub */
2265 			if (hcd->speed != HCD_USB3) {
2266 				dev_dbg(dummy_dev(dum_hcd),
2267 					 "USB_PORT_FEAT_BH_PORT_RESET req not "
2268 					 "supported for USB 2.0 roothub\n");
2269 				goto error;
2270 			}
2271 			fallthrough;
2272 		case USB_PORT_FEAT_RESET:
2273 			if (!(dum_hcd->port_status & USB_PORT_STAT_CONNECTION))
2274 				break;
2275 			/* if it's already enabled, disable */
2276 			if (hcd->speed == HCD_USB3) {
2277 				dum_hcd->port_status =
2278 					(USB_SS_PORT_STAT_POWER |
2279 					 USB_PORT_STAT_CONNECTION |
2280 					 USB_PORT_STAT_RESET);
2281 			} else {
2282 				dum_hcd->port_status &= ~(USB_PORT_STAT_ENABLE
2283 					| USB_PORT_STAT_LOW_SPEED
2284 					| USB_PORT_STAT_HIGH_SPEED);
2285 				dum_hcd->port_status |= USB_PORT_STAT_RESET;
2286 			}
2287 			/*
2288 			 * We want to reset device status. All but the
2289 			 * Self powered feature
2290 			 */
2291 			dum_hcd->dum->devstatus &=
2292 				(1 << USB_DEVICE_SELF_POWERED);
2293 			/*
2294 			 * FIXME USB3.0: what is the correct reset signaling
2295 			 * interval? Is it still 50msec as for HS?
2296 			 */
2297 			dum_hcd->re_timeout = jiffies + msecs_to_jiffies(50);
2298 			set_link_state(dum_hcd);
2299 			break;
2300 		case USB_PORT_FEAT_C_CONNECTION:
2301 		case USB_PORT_FEAT_C_RESET:
2302 		case USB_PORT_FEAT_C_ENABLE:
2303 		case USB_PORT_FEAT_C_SUSPEND:
2304 			/* Not allowed for USB-3, and ignored for USB-2 */
2305 			if (hcd->speed == HCD_USB3)
2306 				goto error;
2307 			break;
2308 		default:
2309 		/* Disallow TEST, INDICATOR, and C_OVER_CURRENT */
2310 			goto error;
2311 		}
2312 		break;
2313 	case GetPortErrorCount:
2314 		if (hcd->speed != HCD_USB3) {
2315 			dev_dbg(dummy_dev(dum_hcd),
2316 				 "GetPortErrorCount req not "
2317 				 "supported for USB 2.0 roothub\n");
2318 			goto error;
2319 		}
2320 		/* We'll always return 0 since this is a dummy hub */
2321 		*(__le32 *) buf = cpu_to_le32(0);
2322 		break;
2323 	case SetHubDepth:
2324 		if (hcd->speed != HCD_USB3) {
2325 			dev_dbg(dummy_dev(dum_hcd),
2326 				 "SetHubDepth req not supported for "
2327 				 "USB 2.0 roothub\n");
2328 			goto error;
2329 		}
2330 		break;
2331 	default:
2332 		dev_dbg(dummy_dev(dum_hcd),
2333 			"hub control req%04x v%04x i%04x l%d\n",
2334 			typeReq, wValue, wIndex, wLength);
2335 error:
2336 		/* "protocol stall" on error */
2337 		retval = -EPIPE;
2338 	}
2339 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2340 
2341 	if ((dum_hcd->port_status & PORT_C_MASK) != 0)
2342 		usb_hcd_poll_rh_status(hcd);
2343 	return retval;
2344 }
2345 
2346 static int dummy_bus_suspend(struct usb_hcd *hcd)
2347 {
2348 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2349 
2350 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
2351 
2352 	spin_lock_irq(&dum_hcd->dum->lock);
2353 	dum_hcd->rh_state = DUMMY_RH_SUSPENDED;
2354 	set_link_state(dum_hcd);
2355 	hcd->state = HC_STATE_SUSPENDED;
2356 	spin_unlock_irq(&dum_hcd->dum->lock);
2357 	return 0;
2358 }
2359 
2360 static int dummy_bus_resume(struct usb_hcd *hcd)
2361 {
2362 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2363 	int rc = 0;
2364 
2365 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
2366 
2367 	spin_lock_irq(&dum_hcd->dum->lock);
2368 	if (!HCD_HW_ACCESSIBLE(hcd)) {
2369 		rc = -ESHUTDOWN;
2370 	} else {
2371 		dum_hcd->rh_state = DUMMY_RH_RUNNING;
2372 		set_link_state(dum_hcd);
2373 		if (!list_empty(&dum_hcd->urbp_list))
2374 			mod_timer(&dum_hcd->timer, jiffies);
2375 		hcd->state = HC_STATE_RUNNING;
2376 	}
2377 	spin_unlock_irq(&dum_hcd->dum->lock);
2378 	return rc;
2379 }
2380 
2381 /*-------------------------------------------------------------------------*/
2382 
2383 static inline ssize_t show_urb(char *buf, size_t size, struct urb *urb)
2384 {
2385 	int ep = usb_pipeendpoint(urb->pipe);
2386 
2387 	return scnprintf(buf, size,
2388 		"urb/%p %s ep%d%s%s len %d/%d\n",
2389 		urb,
2390 		({ char *s;
2391 		switch (urb->dev->speed) {
2392 		case USB_SPEED_LOW:
2393 			s = "ls";
2394 			break;
2395 		case USB_SPEED_FULL:
2396 			s = "fs";
2397 			break;
2398 		case USB_SPEED_HIGH:
2399 			s = "hs";
2400 			break;
2401 		case USB_SPEED_SUPER:
2402 			s = "ss";
2403 			break;
2404 		default:
2405 			s = "?";
2406 			break;
2407 		 } s; }),
2408 		ep, ep ? (usb_urb_dir_in(urb) ? "in" : "out") : "",
2409 		({ char *s; \
2410 		switch (usb_pipetype(urb->pipe)) { \
2411 		case PIPE_CONTROL: \
2412 			s = ""; \
2413 			break; \
2414 		case PIPE_BULK: \
2415 			s = "-bulk"; \
2416 			break; \
2417 		case PIPE_INTERRUPT: \
2418 			s = "-int"; \
2419 			break; \
2420 		default: \
2421 			s = "-iso"; \
2422 			break; \
2423 		} s; }),
2424 		urb->actual_length, urb->transfer_buffer_length);
2425 }
2426 
2427 static ssize_t urbs_show(struct device *dev, struct device_attribute *attr,
2428 		char *buf)
2429 {
2430 	struct usb_hcd		*hcd = dev_get_drvdata(dev);
2431 	struct dummy_hcd	*dum_hcd = hcd_to_dummy_hcd(hcd);
2432 	struct urbp		*urbp;
2433 	size_t			size = 0;
2434 	unsigned long		flags;
2435 
2436 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2437 	list_for_each_entry(urbp, &dum_hcd->urbp_list, urbp_list) {
2438 		size_t		temp;
2439 
2440 		temp = show_urb(buf, PAGE_SIZE - size, urbp->urb);
2441 		buf += temp;
2442 		size += temp;
2443 	}
2444 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2445 
2446 	return size;
2447 }
2448 static DEVICE_ATTR_RO(urbs);
2449 
2450 static int dummy_start_ss(struct dummy_hcd *dum_hcd)
2451 {
2452 	timer_setup(&dum_hcd->timer, dummy_timer, 0);
2453 	dum_hcd->rh_state = DUMMY_RH_RUNNING;
2454 	dum_hcd->stream_en_ep = 0;
2455 	INIT_LIST_HEAD(&dum_hcd->urbp_list);
2456 	dummy_hcd_to_hcd(dum_hcd)->power_budget = POWER_BUDGET_3;
2457 	dummy_hcd_to_hcd(dum_hcd)->state = HC_STATE_RUNNING;
2458 	dummy_hcd_to_hcd(dum_hcd)->uses_new_polling = 1;
2459 #ifdef CONFIG_USB_OTG
2460 	dummy_hcd_to_hcd(dum_hcd)->self.otg_port = 1;
2461 #endif
2462 	return 0;
2463 
2464 	/* FIXME 'urbs' should be a per-device thing, maybe in usbcore */
2465 	return device_create_file(dummy_dev(dum_hcd), &dev_attr_urbs);
2466 }
2467 
2468 static int dummy_start(struct usb_hcd *hcd)
2469 {
2470 	struct dummy_hcd	*dum_hcd = hcd_to_dummy_hcd(hcd);
2471 
2472 	/*
2473 	 * HOST side init ... we emulate a root hub that'll only ever
2474 	 * talk to one device (the gadget side).  Also appears in sysfs,
2475 	 * just like more familiar pci-based HCDs.
2476 	 */
2477 	if (!usb_hcd_is_primary_hcd(hcd))
2478 		return dummy_start_ss(dum_hcd);
2479 
2480 	spin_lock_init(&dum_hcd->dum->lock);
2481 	timer_setup(&dum_hcd->timer, dummy_timer, 0);
2482 	dum_hcd->rh_state = DUMMY_RH_RUNNING;
2483 
2484 	INIT_LIST_HEAD(&dum_hcd->urbp_list);
2485 
2486 	hcd->power_budget = POWER_BUDGET;
2487 	hcd->state = HC_STATE_RUNNING;
2488 	hcd->uses_new_polling = 1;
2489 
2490 #ifdef CONFIG_USB_OTG
2491 	hcd->self.otg_port = 1;
2492 #endif
2493 
2494 	/* FIXME 'urbs' should be a per-device thing, maybe in usbcore */
2495 	return device_create_file(dummy_dev(dum_hcd), &dev_attr_urbs);
2496 }
2497 
2498 static void dummy_stop(struct usb_hcd *hcd)
2499 {
2500 	device_remove_file(dummy_dev(hcd_to_dummy_hcd(hcd)), &dev_attr_urbs);
2501 	dev_info(dummy_dev(hcd_to_dummy_hcd(hcd)), "stopped\n");
2502 }
2503 
2504 /*-------------------------------------------------------------------------*/
2505 
2506 static int dummy_h_get_frame(struct usb_hcd *hcd)
2507 {
2508 	return dummy_g_get_frame(NULL);
2509 }
2510 
2511 static int dummy_setup(struct usb_hcd *hcd)
2512 {
2513 	struct dummy *dum;
2514 
2515 	dum = *((void **)dev_get_platdata(hcd->self.controller));
2516 	hcd->self.sg_tablesize = ~0;
2517 	if (usb_hcd_is_primary_hcd(hcd)) {
2518 		dum->hs_hcd = hcd_to_dummy_hcd(hcd);
2519 		dum->hs_hcd->dum = dum;
2520 		/*
2521 		 * Mark the first roothub as being USB 2.0.
2522 		 * The USB 3.0 roothub will be registered later by
2523 		 * dummy_hcd_probe()
2524 		 */
2525 		hcd->speed = HCD_USB2;
2526 		hcd->self.root_hub->speed = USB_SPEED_HIGH;
2527 	} else {
2528 		dum->ss_hcd = hcd_to_dummy_hcd(hcd);
2529 		dum->ss_hcd->dum = dum;
2530 		hcd->speed = HCD_USB3;
2531 		hcd->self.root_hub->speed = USB_SPEED_SUPER;
2532 	}
2533 	return 0;
2534 }
2535 
2536 /* Change a group of bulk endpoints to support multiple stream IDs */
2537 static int dummy_alloc_streams(struct usb_hcd *hcd, struct usb_device *udev,
2538 	struct usb_host_endpoint **eps, unsigned int num_eps,
2539 	unsigned int num_streams, gfp_t mem_flags)
2540 {
2541 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2542 	unsigned long flags;
2543 	int max_stream;
2544 	int ret_streams = num_streams;
2545 	unsigned int index;
2546 	unsigned int i;
2547 
2548 	if (!num_eps)
2549 		return -EINVAL;
2550 
2551 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2552 	for (i = 0; i < num_eps; i++) {
2553 		index = dummy_get_ep_idx(&eps[i]->desc);
2554 		if ((1 << index) & dum_hcd->stream_en_ep) {
2555 			ret_streams = -EINVAL;
2556 			goto out;
2557 		}
2558 		max_stream = usb_ss_max_streams(&eps[i]->ss_ep_comp);
2559 		if (!max_stream) {
2560 			ret_streams = -EINVAL;
2561 			goto out;
2562 		}
2563 		if (max_stream < ret_streams) {
2564 			dev_dbg(dummy_dev(dum_hcd), "Ep 0x%x only supports %u "
2565 					"stream IDs.\n",
2566 					eps[i]->desc.bEndpointAddress,
2567 					max_stream);
2568 			ret_streams = max_stream;
2569 		}
2570 	}
2571 
2572 	for (i = 0; i < num_eps; i++) {
2573 		index = dummy_get_ep_idx(&eps[i]->desc);
2574 		dum_hcd->stream_en_ep |= 1 << index;
2575 		set_max_streams_for_pipe(dum_hcd,
2576 				usb_endpoint_num(&eps[i]->desc), ret_streams);
2577 	}
2578 out:
2579 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2580 	return ret_streams;
2581 }
2582 
2583 /* Reverts a group of bulk endpoints back to not using stream IDs. */
2584 static int dummy_free_streams(struct usb_hcd *hcd, struct usb_device *udev,
2585 	struct usb_host_endpoint **eps, unsigned int num_eps,
2586 	gfp_t mem_flags)
2587 {
2588 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2589 	unsigned long flags;
2590 	int ret;
2591 	unsigned int index;
2592 	unsigned int i;
2593 
2594 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2595 	for (i = 0; i < num_eps; i++) {
2596 		index = dummy_get_ep_idx(&eps[i]->desc);
2597 		if (!((1 << index) & dum_hcd->stream_en_ep)) {
2598 			ret = -EINVAL;
2599 			goto out;
2600 		}
2601 	}
2602 
2603 	for (i = 0; i < num_eps; i++) {
2604 		index = dummy_get_ep_idx(&eps[i]->desc);
2605 		dum_hcd->stream_en_ep &= ~(1 << index);
2606 		set_max_streams_for_pipe(dum_hcd,
2607 				usb_endpoint_num(&eps[i]->desc), 0);
2608 	}
2609 	ret = 0;
2610 out:
2611 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2612 	return ret;
2613 }
2614 
2615 static struct hc_driver dummy_hcd = {
2616 	.description =		(char *) driver_name,
2617 	.product_desc =		"Dummy host controller",
2618 	.hcd_priv_size =	sizeof(struct dummy_hcd),
2619 
2620 	.reset =		dummy_setup,
2621 	.start =		dummy_start,
2622 	.stop =			dummy_stop,
2623 
2624 	.urb_enqueue =		dummy_urb_enqueue,
2625 	.urb_dequeue =		dummy_urb_dequeue,
2626 
2627 	.get_frame_number =	dummy_h_get_frame,
2628 
2629 	.hub_status_data =	dummy_hub_status,
2630 	.hub_control =		dummy_hub_control,
2631 	.bus_suspend =		dummy_bus_suspend,
2632 	.bus_resume =		dummy_bus_resume,
2633 
2634 	.alloc_streams =	dummy_alloc_streams,
2635 	.free_streams =		dummy_free_streams,
2636 };
2637 
2638 static int dummy_hcd_probe(struct platform_device *pdev)
2639 {
2640 	struct dummy		*dum;
2641 	struct usb_hcd		*hs_hcd;
2642 	struct usb_hcd		*ss_hcd;
2643 	int			retval;
2644 
2645 	dev_info(&pdev->dev, "%s, driver " DRIVER_VERSION "\n", driver_desc);
2646 	dum = *((void **)dev_get_platdata(&pdev->dev));
2647 
2648 	if (mod_data.is_super_speed)
2649 		dummy_hcd.flags = HCD_USB3 | HCD_SHARED;
2650 	else if (mod_data.is_high_speed)
2651 		dummy_hcd.flags = HCD_USB2;
2652 	else
2653 		dummy_hcd.flags = HCD_USB11;
2654 	hs_hcd = usb_create_hcd(&dummy_hcd, &pdev->dev, dev_name(&pdev->dev));
2655 	if (!hs_hcd)
2656 		return -ENOMEM;
2657 	hs_hcd->has_tt = 1;
2658 
2659 	retval = usb_add_hcd(hs_hcd, 0, 0);
2660 	if (retval)
2661 		goto put_usb2_hcd;
2662 
2663 	if (mod_data.is_super_speed) {
2664 		ss_hcd = usb_create_shared_hcd(&dummy_hcd, &pdev->dev,
2665 					dev_name(&pdev->dev), hs_hcd);
2666 		if (!ss_hcd) {
2667 			retval = -ENOMEM;
2668 			goto dealloc_usb2_hcd;
2669 		}
2670 
2671 		retval = usb_add_hcd(ss_hcd, 0, 0);
2672 		if (retval)
2673 			goto put_usb3_hcd;
2674 	}
2675 	return 0;
2676 
2677 put_usb3_hcd:
2678 	usb_put_hcd(ss_hcd);
2679 dealloc_usb2_hcd:
2680 	usb_remove_hcd(hs_hcd);
2681 put_usb2_hcd:
2682 	usb_put_hcd(hs_hcd);
2683 	dum->hs_hcd = dum->ss_hcd = NULL;
2684 	return retval;
2685 }
2686 
2687 static int dummy_hcd_remove(struct platform_device *pdev)
2688 {
2689 	struct dummy		*dum;
2690 
2691 	dum = hcd_to_dummy_hcd(platform_get_drvdata(pdev))->dum;
2692 
2693 	if (dum->ss_hcd) {
2694 		usb_remove_hcd(dummy_hcd_to_hcd(dum->ss_hcd));
2695 		usb_put_hcd(dummy_hcd_to_hcd(dum->ss_hcd));
2696 	}
2697 
2698 	usb_remove_hcd(dummy_hcd_to_hcd(dum->hs_hcd));
2699 	usb_put_hcd(dummy_hcd_to_hcd(dum->hs_hcd));
2700 
2701 	dum->hs_hcd = NULL;
2702 	dum->ss_hcd = NULL;
2703 
2704 	return 0;
2705 }
2706 
2707 static int dummy_hcd_suspend(struct platform_device *pdev, pm_message_t state)
2708 {
2709 	struct usb_hcd		*hcd;
2710 	struct dummy_hcd	*dum_hcd;
2711 	int			rc = 0;
2712 
2713 	dev_dbg(&pdev->dev, "%s\n", __func__);
2714 
2715 	hcd = platform_get_drvdata(pdev);
2716 	dum_hcd = hcd_to_dummy_hcd(hcd);
2717 	if (dum_hcd->rh_state == DUMMY_RH_RUNNING) {
2718 		dev_warn(&pdev->dev, "Root hub isn't suspended!\n");
2719 		rc = -EBUSY;
2720 	} else
2721 		clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2722 	return rc;
2723 }
2724 
2725 static int dummy_hcd_resume(struct platform_device *pdev)
2726 {
2727 	struct usb_hcd		*hcd;
2728 
2729 	dev_dbg(&pdev->dev, "%s\n", __func__);
2730 
2731 	hcd = platform_get_drvdata(pdev);
2732 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2733 	usb_hcd_poll_rh_status(hcd);
2734 	return 0;
2735 }
2736 
2737 static struct platform_driver dummy_hcd_driver = {
2738 	.probe		= dummy_hcd_probe,
2739 	.remove		= dummy_hcd_remove,
2740 	.suspend	= dummy_hcd_suspend,
2741 	.resume		= dummy_hcd_resume,
2742 	.driver		= {
2743 		.name	= driver_name,
2744 	},
2745 };
2746 
2747 /*-------------------------------------------------------------------------*/
2748 #define MAX_NUM_UDC	32
2749 static struct platform_device *the_udc_pdev[MAX_NUM_UDC];
2750 static struct platform_device *the_hcd_pdev[MAX_NUM_UDC];
2751 
2752 static int __init init(void)
2753 {
2754 	int	retval = -ENOMEM;
2755 	int	i;
2756 	struct	dummy *dum[MAX_NUM_UDC] = {};
2757 
2758 	if (usb_disabled())
2759 		return -ENODEV;
2760 
2761 	if (!mod_data.is_high_speed && mod_data.is_super_speed)
2762 		return -EINVAL;
2763 
2764 	if (mod_data.num < 1 || mod_data.num > MAX_NUM_UDC) {
2765 		pr_err("Number of emulated UDC must be in range of 1...%d\n",
2766 				MAX_NUM_UDC);
2767 		return -EINVAL;
2768 	}
2769 
2770 	for (i = 0; i < mod_data.num; i++) {
2771 		the_hcd_pdev[i] = platform_device_alloc(driver_name, i);
2772 		if (!the_hcd_pdev[i]) {
2773 			i--;
2774 			while (i >= 0)
2775 				platform_device_put(the_hcd_pdev[i--]);
2776 			return retval;
2777 		}
2778 	}
2779 	for (i = 0; i < mod_data.num; i++) {
2780 		the_udc_pdev[i] = platform_device_alloc(gadget_name, i);
2781 		if (!the_udc_pdev[i]) {
2782 			i--;
2783 			while (i >= 0)
2784 				platform_device_put(the_udc_pdev[i--]);
2785 			goto err_alloc_udc;
2786 		}
2787 	}
2788 	for (i = 0; i < mod_data.num; i++) {
2789 		dum[i] = kzalloc(sizeof(struct dummy), GFP_KERNEL);
2790 		if (!dum[i]) {
2791 			retval = -ENOMEM;
2792 			goto err_add_pdata;
2793 		}
2794 		retval = platform_device_add_data(the_hcd_pdev[i], &dum[i],
2795 				sizeof(void *));
2796 		if (retval)
2797 			goto err_add_pdata;
2798 		retval = platform_device_add_data(the_udc_pdev[i], &dum[i],
2799 				sizeof(void *));
2800 		if (retval)
2801 			goto err_add_pdata;
2802 	}
2803 
2804 	retval = platform_driver_register(&dummy_hcd_driver);
2805 	if (retval < 0)
2806 		goto err_add_pdata;
2807 	retval = platform_driver_register(&dummy_udc_driver);
2808 	if (retval < 0)
2809 		goto err_register_udc_driver;
2810 
2811 	for (i = 0; i < mod_data.num; i++) {
2812 		retval = platform_device_add(the_hcd_pdev[i]);
2813 		if (retval < 0) {
2814 			i--;
2815 			while (i >= 0)
2816 				platform_device_del(the_hcd_pdev[i--]);
2817 			goto err_add_hcd;
2818 		}
2819 	}
2820 	for (i = 0; i < mod_data.num; i++) {
2821 		if (!dum[i]->hs_hcd ||
2822 				(!dum[i]->ss_hcd && mod_data.is_super_speed)) {
2823 			/*
2824 			 * The hcd was added successfully but its probe
2825 			 * function failed for some reason.
2826 			 */
2827 			retval = -EINVAL;
2828 			goto err_add_udc;
2829 		}
2830 	}
2831 
2832 	for (i = 0; i < mod_data.num; i++) {
2833 		retval = platform_device_add(the_udc_pdev[i]);
2834 		if (retval < 0) {
2835 			i--;
2836 			while (i >= 0)
2837 				platform_device_del(the_udc_pdev[i--]);
2838 			goto err_add_udc;
2839 		}
2840 	}
2841 
2842 	for (i = 0; i < mod_data.num; i++) {
2843 		if (!platform_get_drvdata(the_udc_pdev[i])) {
2844 			/*
2845 			 * The udc was added successfully but its probe
2846 			 * function failed for some reason.
2847 			 */
2848 			retval = -EINVAL;
2849 			goto err_probe_udc;
2850 		}
2851 	}
2852 	return retval;
2853 
2854 err_probe_udc:
2855 	for (i = 0; i < mod_data.num; i++)
2856 		platform_device_del(the_udc_pdev[i]);
2857 err_add_udc:
2858 	for (i = 0; i < mod_data.num; i++)
2859 		platform_device_del(the_hcd_pdev[i]);
2860 err_add_hcd:
2861 	platform_driver_unregister(&dummy_udc_driver);
2862 err_register_udc_driver:
2863 	platform_driver_unregister(&dummy_hcd_driver);
2864 err_add_pdata:
2865 	for (i = 0; i < mod_data.num; i++)
2866 		kfree(dum[i]);
2867 	for (i = 0; i < mod_data.num; i++)
2868 		platform_device_put(the_udc_pdev[i]);
2869 err_alloc_udc:
2870 	for (i = 0; i < mod_data.num; i++)
2871 		platform_device_put(the_hcd_pdev[i]);
2872 	return retval;
2873 }
2874 module_init(init);
2875 
2876 static void __exit cleanup(void)
2877 {
2878 	int i;
2879 
2880 	for (i = 0; i < mod_data.num; i++) {
2881 		struct dummy *dum;
2882 
2883 		dum = *((void **)dev_get_platdata(&the_udc_pdev[i]->dev));
2884 
2885 		platform_device_unregister(the_udc_pdev[i]);
2886 		platform_device_unregister(the_hcd_pdev[i]);
2887 		kfree(dum);
2888 	}
2889 	platform_driver_unregister(&dummy_udc_driver);
2890 	platform_driver_unregister(&dummy_hcd_driver);
2891 }
2892 module_exit(cleanup);
2893