xref: /linux/drivers/usb/gadget/udc/dummy_hcd.c (revision b263ff9b0fc5c1f371d65c4eb196b31263d039ff)
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/string_choices.h>
32 #include <linux/errno.h>
33 #include <linux/init.h>
34 #include <linux/hrtimer.h>
35 #include <linux/list.h>
36 #include <linux/interrupt.h>
37 #include <linux/platform_device.h>
38 #include <linux/usb.h>
39 #include <linux/usb/gadget.h>
40 #include <linux/usb/hcd.h>
41 #include <linux/scatterlist.h>
42 
43 #include <asm/byteorder.h>
44 #include <linux/io.h>
45 #include <asm/irq.h>
46 #include <linux/unaligned.h>
47 
48 #define DRIVER_DESC	"USB Host+Gadget Emulator"
49 #define DRIVER_VERSION	"02 May 2005"
50 
51 #define POWER_BUDGET	500	/* in mA; use 8 for low-power port testing */
52 #define POWER_BUDGET_3	900	/* in mA */
53 
54 #define DUMMY_TIMER_INT_NSECS	125000 /* 1 microframe */
55 
56 static const char	driver_name[] = "dummy_hcd";
57 static const char	driver_desc[] = "USB Host+Gadget Emulator";
58 
59 static const char	gadget_name[] = "dummy_udc";
60 
61 MODULE_DESCRIPTION(DRIVER_DESC);
62 MODULE_AUTHOR("David Brownell");
63 MODULE_LICENSE("GPL");
64 
65 struct dummy_hcd_module_parameters {
66 	bool is_super_speed;
67 	bool is_high_speed;
68 	unsigned int num;
69 };
70 
71 static struct dummy_hcd_module_parameters mod_data = {
72 	.is_super_speed = false,
73 	.is_high_speed = true,
74 	.num = 1,
75 };
76 module_param_named(is_super_speed, mod_data.is_super_speed, bool, S_IRUGO);
77 MODULE_PARM_DESC(is_super_speed, "true to simulate SuperSpeed connection");
78 module_param_named(is_high_speed, mod_data.is_high_speed, bool, S_IRUGO);
79 MODULE_PARM_DESC(is_high_speed, "true to simulate HighSpeed connection");
80 module_param_named(num, mod_data.num, uint, S_IRUGO);
81 MODULE_PARM_DESC(num, "number of emulated controllers");
82 /*-------------------------------------------------------------------------*/
83 
84 /* gadget side driver data structures */
85 struct dummy_ep {
86 	struct list_head		queue;
87 	unsigned long			last_io;	/* jiffies timestamp */
88 	struct usb_gadget		*gadget;
89 	const struct usb_endpoint_descriptor *desc;
90 	struct usb_ep			ep;
91 	unsigned			halted:1;
92 	unsigned			wedged:1;
93 	unsigned			already_seen:1;
94 	unsigned			setup_stage:1;
95 	unsigned			stream_en:1;
96 };
97 
98 struct dummy_request {
99 	struct list_head		queue;		/* ep's requests */
100 	struct usb_request		req;
101 };
102 
103 static inline struct dummy_ep *usb_ep_to_dummy_ep(struct usb_ep *_ep)
104 {
105 	return container_of(_ep, struct dummy_ep, ep);
106 }
107 
108 static inline struct dummy_request *usb_request_to_dummy_request
109 		(struct usb_request *_req)
110 {
111 	return container_of(_req, struct dummy_request, req);
112 }
113 
114 /*-------------------------------------------------------------------------*/
115 
116 /*
117  * Every device has ep0 for control requests, plus up to 30 more endpoints,
118  * in one of two types:
119  *
120  *   - Configurable:  direction (in/out), type (bulk, iso, etc), and endpoint
121  *     number can be changed.  Names like "ep-a" are used for this type.
122  *
123  *   - Fixed Function:  in other cases.  some characteristics may be mutable;
124  *     that'd be hardware-specific.  Names like "ep12out-bulk" are used.
125  *
126  * Gadget drivers are responsible for not setting up conflicting endpoint
127  * configurations, illegal or unsupported packet lengths, and so on.
128  */
129 
130 static const char ep0name[] = "ep0";
131 
132 static const struct {
133 	const char *name;
134 	const struct usb_ep_caps caps;
135 } ep_info[] = {
136 #define EP_INFO(_name, _caps) \
137 	{ \
138 		.name = _name, \
139 		.caps = _caps, \
140 	}
141 
142 /* we don't provide isochronous endpoints since we don't support them */
143 #define TYPE_BULK_OR_INT	(USB_EP_CAPS_TYPE_BULK | USB_EP_CAPS_TYPE_INT)
144 
145 	/* everyone has ep0 */
146 	EP_INFO(ep0name,
147 		USB_EP_CAPS(USB_EP_CAPS_TYPE_CONTROL, USB_EP_CAPS_DIR_ALL)),
148 	/* act like a pxa250: fifteen fixed function endpoints */
149 	EP_INFO("ep1in-bulk",
150 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_IN)),
151 	EP_INFO("ep2out-bulk",
152 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_OUT)),
153 /*
154 	EP_INFO("ep3in-iso",
155 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_IN)),
156 	EP_INFO("ep4out-iso",
157 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_OUT)),
158 */
159 	EP_INFO("ep5in-int",
160 		USB_EP_CAPS(USB_EP_CAPS_TYPE_INT, USB_EP_CAPS_DIR_IN)),
161 	EP_INFO("ep6in-bulk",
162 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_IN)),
163 	EP_INFO("ep7out-bulk",
164 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_OUT)),
165 /*
166 	EP_INFO("ep8in-iso",
167 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_IN)),
168 	EP_INFO("ep9out-iso",
169 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_OUT)),
170 */
171 	EP_INFO("ep10in-int",
172 		USB_EP_CAPS(USB_EP_CAPS_TYPE_INT, USB_EP_CAPS_DIR_IN)),
173 	EP_INFO("ep11in-bulk",
174 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_IN)),
175 	EP_INFO("ep12out-bulk",
176 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_OUT)),
177 /*
178 	EP_INFO("ep13in-iso",
179 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_IN)),
180 	EP_INFO("ep14out-iso",
181 		USB_EP_CAPS(USB_EP_CAPS_TYPE_ISO, USB_EP_CAPS_DIR_OUT)),
182 */
183 	EP_INFO("ep15in-int",
184 		USB_EP_CAPS(USB_EP_CAPS_TYPE_INT, USB_EP_CAPS_DIR_IN)),
185 
186 	/* or like sa1100: two fixed function endpoints */
187 	EP_INFO("ep1out-bulk",
188 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_OUT)),
189 	EP_INFO("ep2in-bulk",
190 		USB_EP_CAPS(USB_EP_CAPS_TYPE_BULK, USB_EP_CAPS_DIR_IN)),
191 
192 	/* and now some generic EPs so we have enough in multi config */
193 	EP_INFO("ep-aout",
194 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
195 	EP_INFO("ep-bin",
196 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
197 	EP_INFO("ep-cout",
198 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
199 	EP_INFO("ep-dout",
200 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
201 	EP_INFO("ep-ein",
202 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
203 	EP_INFO("ep-fout",
204 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
205 	EP_INFO("ep-gin",
206 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
207 	EP_INFO("ep-hout",
208 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
209 	EP_INFO("ep-iout",
210 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
211 	EP_INFO("ep-jin",
212 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
213 	EP_INFO("ep-kout",
214 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
215 	EP_INFO("ep-lin",
216 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_IN)),
217 	EP_INFO("ep-mout",
218 		USB_EP_CAPS(TYPE_BULK_OR_INT, USB_EP_CAPS_DIR_OUT)),
219 
220 #undef EP_INFO
221 };
222 
223 #define DUMMY_ENDPOINTS	ARRAY_SIZE(ep_info)
224 
225 /*-------------------------------------------------------------------------*/
226 
227 #define FIFO_SIZE		64
228 
229 struct urbp {
230 	struct urb		*urb;
231 	struct list_head	urbp_list;
232 	struct sg_mapping_iter	miter;
233 	u32			miter_started;
234 };
235 
236 
237 enum dummy_rh_state {
238 	DUMMY_RH_RESET,
239 	DUMMY_RH_SUSPENDED,
240 	DUMMY_RH_RUNNING
241 };
242 
243 struct dummy_hcd {
244 	struct dummy			*dum;
245 	enum dummy_rh_state		rh_state;
246 	struct hrtimer			timer;
247 	u32				port_status;
248 	u32				old_status;
249 	unsigned long			re_timeout;
250 
251 	struct usb_device		*udev;
252 	struct list_head		urbp_list;
253 	struct urbp			*next_frame_urbp;
254 
255 	u32				stream_en_ep;
256 	u8				num_stream[30 / 2];
257 
258 	unsigned			timer_pending:1;
259 	unsigned			active:1;
260 	unsigned			old_active:1;
261 	unsigned			resuming:1;
262 };
263 
264 struct dummy {
265 	spinlock_t			lock;
266 
267 	/*
268 	 * DEVICE/GADGET side support
269 	 */
270 	struct dummy_ep			ep[DUMMY_ENDPOINTS];
271 	int				address;
272 	int				callback_usage;
273 	struct usb_gadget		gadget;
274 	struct usb_gadget_driver	*driver;
275 	struct dummy_request		fifo_req;
276 	u8				fifo_buf[FIFO_SIZE];
277 	u16				devstatus;
278 	unsigned			ints_enabled:1;
279 	unsigned			udc_suspended:1;
280 	unsigned			pullup:1;
281 	unsigned			fifo_req_busy:1;
282 
283 	/*
284 	 * HOST side support
285 	 */
286 	struct dummy_hcd		*hs_hcd;
287 	struct dummy_hcd		*ss_hcd;
288 };
289 
290 static inline struct dummy_hcd *hcd_to_dummy_hcd(struct usb_hcd *hcd)
291 {
292 	return (struct dummy_hcd *) (hcd->hcd_priv);
293 }
294 
295 static inline struct usb_hcd *dummy_hcd_to_hcd(struct dummy_hcd *dum)
296 {
297 	return container_of((void *) dum, struct usb_hcd, hcd_priv);
298 }
299 
300 static inline struct device *dummy_dev(struct dummy_hcd *dum)
301 {
302 	return dummy_hcd_to_hcd(dum)->self.controller;
303 }
304 
305 static inline struct device *udc_dev(struct dummy *dum)
306 {
307 	return dum->gadget.dev.parent;
308 }
309 
310 static inline struct dummy *ep_to_dummy(struct dummy_ep *ep)
311 {
312 	return container_of(ep->gadget, struct dummy, gadget);
313 }
314 
315 static inline struct dummy_hcd *gadget_to_dummy_hcd(struct usb_gadget *gadget)
316 {
317 	struct dummy *dum = container_of(gadget, struct dummy, gadget);
318 	if (dum->gadget.speed == USB_SPEED_SUPER)
319 		return dum->ss_hcd;
320 	else
321 		return dum->hs_hcd;
322 }
323 
324 static inline struct dummy *gadget_dev_to_dummy(struct device *dev)
325 {
326 	return container_of(dev, struct dummy, gadget.dev);
327 }
328 
329 /*-------------------------------------------------------------------------*/
330 
331 /* DEVICE/GADGET SIDE UTILITY ROUTINES */
332 
333 /*
334  * Give back a gadget request with dum->lock dropped around the callback.
335  * If @req is the shared fifo_req, clear fifo_req_busy afterward: the flag
336  * was set in dummy_queue() when the shared request was taken and must stay
337  * set until its completion callback has returned; list_del_init() alone
338  * makes the request look idle while the callback is still running.
339  * Caller holds dum->lock and has already done list_del_init() + status.
340  */
341 static void dummy_giveback(struct dummy *dum, struct usb_ep *_ep,
342 			   struct dummy_request *req)
343 {
344 	bool fifo = req == &dum->fifo_req;
345 
346 	++dum->callback_usage;
347 	spin_unlock(&dum->lock);
348 	usb_gadget_giveback_request(_ep, &req->req);
349 	spin_lock(&dum->lock);
350 	--dum->callback_usage;
351 	if (fifo)
352 		dum->fifo_req_busy = 0;
353 }
354 
355 /* called with spinlock held */
356 static void nuke(struct dummy *dum, struct dummy_ep *ep)
357 {
358 	while (!list_empty(&ep->queue)) {
359 		struct dummy_request	*req;
360 
361 		req = list_entry(ep->queue.next, struct dummy_request, queue);
362 		list_del_init(&req->queue);
363 		req->req.status = -ESHUTDOWN;
364 
365 		dummy_giveback(dum, &ep->ep, req);
366 	}
367 }
368 
369 /* caller must hold lock */
370 static void stop_activity(struct dummy *dum)
371 {
372 	int i;
373 
374 	/* prevent any more requests */
375 	dum->address = 0;
376 
377 	/* The timer is left running so that outstanding URBs can fail */
378 
379 	/* nuke any pending requests first, so driver i/o is quiesced */
380 	for (i = 0; i < DUMMY_ENDPOINTS; ++i)
381 		nuke(dum, &dum->ep[i]);
382 
383 	/* driver now does any non-usb quiescing necessary */
384 }
385 
386 /**
387  * set_link_state_by_speed() - Sets the current state of the link according to
388  *	the hcd speed
389  * @dum_hcd: pointer to the dummy_hcd structure to update the link state for
390  *
391  * This function updates the port_status according to the link state and the
392  * speed of the hcd.
393  */
394 static void set_link_state_by_speed(struct dummy_hcd *dum_hcd)
395 {
396 	struct dummy *dum = dum_hcd->dum;
397 
398 	if (dummy_hcd_to_hcd(dum_hcd)->speed == HCD_USB3) {
399 		if ((dum_hcd->port_status & USB_SS_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 			if ((dum_hcd->old_status &
406 			     USB_PORT_STAT_CONNECTION) != 0)
407 				dum_hcd->port_status |=
408 					(USB_PORT_STAT_C_CONNECTION << 16);
409 		} else {
410 			/* device is connected and not suspended */
411 			dum_hcd->port_status |= (USB_PORT_STAT_CONNECTION |
412 						 USB_PORT_STAT_SPEED_5GBPS) ;
413 			if ((dum_hcd->old_status &
414 			     USB_PORT_STAT_CONNECTION) == 0)
415 				dum_hcd->port_status |=
416 					(USB_PORT_STAT_C_CONNECTION << 16);
417 			if ((dum_hcd->port_status & USB_PORT_STAT_ENABLE) &&
418 			    (dum_hcd->port_status &
419 			     USB_PORT_STAT_LINK_STATE) == USB_SS_PORT_LS_U0 &&
420 			    dum_hcd->rh_state != DUMMY_RH_SUSPENDED)
421 				dum_hcd->active = 1;
422 		}
423 	} else {
424 		if ((dum_hcd->port_status & USB_PORT_STAT_POWER) == 0) {
425 			dum_hcd->port_status = 0;
426 		} else if (!dum->pullup || dum->udc_suspended) {
427 			/* UDC suspend must cause a disconnect */
428 			dum_hcd->port_status &= ~(USB_PORT_STAT_CONNECTION |
429 						USB_PORT_STAT_ENABLE |
430 						USB_PORT_STAT_LOW_SPEED |
431 						USB_PORT_STAT_HIGH_SPEED |
432 						USB_PORT_STAT_SUSPEND);
433 			if ((dum_hcd->old_status &
434 			     USB_PORT_STAT_CONNECTION) != 0)
435 				dum_hcd->port_status |=
436 					(USB_PORT_STAT_C_CONNECTION << 16);
437 		} else {
438 			dum_hcd->port_status |= USB_PORT_STAT_CONNECTION;
439 			if ((dum_hcd->old_status &
440 			     USB_PORT_STAT_CONNECTION) == 0)
441 				dum_hcd->port_status |=
442 					(USB_PORT_STAT_C_CONNECTION << 16);
443 			if ((dum_hcd->port_status & USB_PORT_STAT_ENABLE) == 0)
444 				dum_hcd->port_status &= ~USB_PORT_STAT_SUSPEND;
445 			else if ((dum_hcd->port_status &
446 				  USB_PORT_STAT_SUSPEND) == 0 &&
447 					dum_hcd->rh_state != DUMMY_RH_SUSPENDED)
448 				dum_hcd->active = 1;
449 		}
450 	}
451 }
452 
453 /* caller must hold lock */
454 static void set_link_state(struct dummy_hcd *dum_hcd)
455 	__must_hold(&dum->lock)
456 {
457 	struct dummy *dum = dum_hcd->dum;
458 	unsigned int power_bit;
459 
460 	dum_hcd->active = 0;
461 	if (dum->pullup)
462 		if ((dummy_hcd_to_hcd(dum_hcd)->speed == HCD_USB3 &&
463 		     dum->gadget.speed != USB_SPEED_SUPER) ||
464 		    (dummy_hcd_to_hcd(dum_hcd)->speed != HCD_USB3 &&
465 		     dum->gadget.speed == USB_SPEED_SUPER))
466 			return;
467 
468 	set_link_state_by_speed(dum_hcd);
469 	power_bit = (dummy_hcd_to_hcd(dum_hcd)->speed == HCD_USB3 ?
470 			USB_SS_PORT_STAT_POWER : USB_PORT_STAT_POWER);
471 
472 	if ((dum_hcd->port_status & USB_PORT_STAT_ENABLE) == 0 ||
473 	     dum_hcd->active)
474 		dum_hcd->resuming = 0;
475 
476 	/* Currently !connected or in reset */
477 	if ((dum_hcd->port_status & power_bit) == 0 ||
478 			(dum_hcd->port_status & USB_PORT_STAT_RESET) != 0) {
479 		unsigned int disconnect = power_bit &
480 				dum_hcd->old_status & (~dum_hcd->port_status);
481 		unsigned int reset = USB_PORT_STAT_RESET &
482 				(~dum_hcd->old_status) & dum_hcd->port_status;
483 
484 		/* Report reset and disconnect events to the driver */
485 		if (dum->ints_enabled && (disconnect || reset)) {
486 			++dum->callback_usage;
487 			/*
488 			 * stop_activity() can drop dum->lock, so it must
489 			 * not come between the dum->ints_enabled test
490 			 * and the ++dum->callback_usage.
491 			 */
492 			stop_activity(dum);
493 			spin_unlock(&dum->lock);
494 			if (reset)
495 				usb_gadget_udc_reset(&dum->gadget, dum->driver);
496 			else
497 				dum->driver->disconnect(&dum->gadget);
498 			spin_lock(&dum->lock);
499 			--dum->callback_usage;
500 		}
501 	} else if (dum_hcd->active != dum_hcd->old_active &&
502 			dum->ints_enabled) {
503 		++dum->callback_usage;
504 		spin_unlock(&dum->lock);
505 		if (dum_hcd->old_active && dum->driver->suspend)
506 			dum->driver->suspend(&dum->gadget);
507 		else if (!dum_hcd->old_active &&  dum->driver->resume)
508 			dum->driver->resume(&dum->gadget);
509 		spin_lock(&dum->lock);
510 		--dum->callback_usage;
511 	}
512 
513 	dum_hcd->old_status = dum_hcd->port_status;
514 	dum_hcd->old_active = dum_hcd->active;
515 }
516 
517 /*-------------------------------------------------------------------------*/
518 
519 /* DEVICE/GADGET SIDE DRIVER
520  *
521  * This only tracks gadget state.  All the work is done when the host
522  * side tries some (emulated) i/o operation.  Real device controller
523  * drivers would do real i/o using dma, fifos, irqs, timers, etc.
524  */
525 
526 #define is_enabled(dum) \
527 	(dum->port_status & USB_PORT_STAT_ENABLE)
528 
529 static int dummy_enable(struct usb_ep *_ep,
530 		const struct usb_endpoint_descriptor *desc)
531 {
532 	struct dummy		*dum;
533 	struct dummy_hcd	*dum_hcd;
534 	struct dummy_ep		*ep;
535 	unsigned		max;
536 	int			retval;
537 
538 	ep = usb_ep_to_dummy_ep(_ep);
539 	if (!_ep || !desc || ep->desc || _ep->name == ep0name
540 			|| desc->bDescriptorType != USB_DT_ENDPOINT)
541 		return -EINVAL;
542 	dum = ep_to_dummy(ep);
543 	if (!dum->driver)
544 		return -ESHUTDOWN;
545 
546 	dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
547 	if (!is_enabled(dum_hcd))
548 		return -ESHUTDOWN;
549 
550 	/*
551 	 * For HS/FS devices only bits 0..10 of the wMaxPacketSize represent the
552 	 * maximum packet size.
553 	 * For SS devices the wMaxPacketSize is limited by 1024.
554 	 */
555 	max = usb_endpoint_maxp(desc);
556 
557 	/* drivers must not request bad settings, since lower levels
558 	 * (hardware or its drivers) may not check.  some endpoints
559 	 * can't do iso, many have maxpacket limitations, etc.
560 	 *
561 	 * since this "hardware" driver is here to help debugging, we
562 	 * have some extra sanity checks.  (there could be more though,
563 	 * especially for "ep9out" style fixed function ones.)
564 	 */
565 	retval = -EINVAL;
566 	switch (usb_endpoint_type(desc)) {
567 	case USB_ENDPOINT_XFER_BULK:
568 		if (strstr(ep->ep.name, "-iso")
569 				|| strstr(ep->ep.name, "-int")) {
570 			goto done;
571 		}
572 		switch (dum->gadget.speed) {
573 		case USB_SPEED_SUPER:
574 			if (max == 1024)
575 				break;
576 			goto done;
577 		case USB_SPEED_HIGH:
578 			if (max == 512)
579 				break;
580 			goto done;
581 		case USB_SPEED_FULL:
582 			if (max == 8 || max == 16 || max == 32 || max == 64)
583 				/* we'll fake any legal size */
584 				break;
585 			/* save a return statement */
586 			fallthrough;
587 		default:
588 			goto done;
589 		}
590 		break;
591 	case USB_ENDPOINT_XFER_INT:
592 		if (strstr(ep->ep.name, "-iso")) /* bulk is ok */
593 			goto done;
594 		/* real hardware might not handle all packet sizes */
595 		switch (dum->gadget.speed) {
596 		case USB_SPEED_SUPER:
597 		case USB_SPEED_HIGH:
598 			if (max <= 1024)
599 				break;
600 			/* save a return statement */
601 			fallthrough;
602 		case USB_SPEED_FULL:
603 			if (max <= 64)
604 				break;
605 			/* save a return statement */
606 			fallthrough;
607 		default:
608 			if (max <= 8)
609 				break;
610 			goto done;
611 		}
612 		break;
613 	case USB_ENDPOINT_XFER_ISOC:
614 		if (strstr(ep->ep.name, "-bulk")
615 				|| strstr(ep->ep.name, "-int"))
616 			goto done;
617 		/* real hardware might not handle all packet sizes */
618 		switch (dum->gadget.speed) {
619 		case USB_SPEED_SUPER:
620 		case USB_SPEED_HIGH:
621 			if (max <= 1024)
622 				break;
623 			/* save a return statement */
624 			fallthrough;
625 		case USB_SPEED_FULL:
626 			if (max <= 1023)
627 				break;
628 			/* save a return statement */
629 			fallthrough;
630 		default:
631 			goto done;
632 		}
633 		break;
634 	default:
635 		/* few chips support control except on ep0 */
636 		goto done;
637 	}
638 
639 	_ep->maxpacket = max;
640 	if (usb_ss_max_streams(_ep->comp_desc)) {
641 		if (!usb_endpoint_xfer_bulk(desc)) {
642 			dev_err(udc_dev(dum), "Can't enable stream support on "
643 					"non-bulk ep %s\n", _ep->name);
644 			return -EINVAL;
645 		}
646 		ep->stream_en = 1;
647 	}
648 	ep->desc = desc;
649 
650 	dev_dbg(udc_dev(dum), "enabled %s (ep%d%s-%s) maxpacket %d stream %s\n",
651 		_ep->name,
652 		usb_endpoint_num(desc),
653 		(desc->bEndpointAddress & USB_DIR_IN) ? "in" : "out",
654 		usb_ep_type_string(usb_endpoint_type(desc)),
655 		max, str_enabled_disabled(ep->stream_en));
656 
657 	/* at this point real hardware should be NAKing transfers
658 	 * to that endpoint, until a buffer is queued to it.
659 	 */
660 	ep->halted = ep->wedged = 0;
661 	retval = 0;
662 done:
663 	return retval;
664 }
665 
666 static int dummy_disable(struct usb_ep *_ep)
667 {
668 	struct dummy_ep		*ep;
669 	struct dummy		*dum;
670 	unsigned long		flags;
671 
672 	ep = usb_ep_to_dummy_ep(_ep);
673 	if (!_ep || !ep->desc || _ep->name == ep0name)
674 		return -EINVAL;
675 	dum = ep_to_dummy(ep);
676 
677 	spin_lock_irqsave(&dum->lock, flags);
678 	ep->desc = NULL;
679 	ep->stream_en = 0;
680 	nuke(dum, ep);
681 	spin_unlock_irqrestore(&dum->lock, flags);
682 
683 	dev_dbg(udc_dev(dum), "disabled %s\n", _ep->name);
684 	return 0;
685 }
686 
687 static struct usb_request *dummy_alloc_request(struct usb_ep *_ep,
688 		gfp_t mem_flags)
689 {
690 	struct dummy_request	*req;
691 
692 	if (!_ep)
693 		return NULL;
694 
695 	req = kzalloc_obj(*req, mem_flags);
696 	if (!req)
697 		return NULL;
698 	INIT_LIST_HEAD(&req->queue);
699 	return &req->req;
700 }
701 
702 static void dummy_free_request(struct usb_ep *_ep, struct usb_request *_req)
703 {
704 	struct dummy_request	*req;
705 
706 	if (!_ep || !_req) {
707 		WARN_ON(1);
708 		return;
709 	}
710 
711 	req = usb_request_to_dummy_request(_req);
712 	WARN_ON(!list_empty(&req->queue));
713 	kfree(req);
714 }
715 
716 static void fifo_complete(struct usb_ep *ep, struct usb_request *req)
717 {
718 }
719 
720 static int dummy_queue(struct usb_ep *_ep, struct usb_request *_req,
721 		gfp_t mem_flags)
722 {
723 	struct dummy_ep		*ep;
724 	struct dummy_request	*req;
725 	struct dummy		*dum;
726 	struct dummy_hcd	*dum_hcd;
727 	unsigned long		flags;
728 
729 	req = usb_request_to_dummy_request(_req);
730 	if (!_req || !list_empty(&req->queue) || !_req->complete)
731 		return -EINVAL;
732 
733 	ep = usb_ep_to_dummy_ep(_ep);
734 	if (!_ep || (!ep->desc && _ep->name != ep0name))
735 		return -EINVAL;
736 
737 	dum = ep_to_dummy(ep);
738 	dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
739 	if (!dum->driver || !is_enabled(dum_hcd))
740 		return -ESHUTDOWN;
741 
742 #if 0
743 	dev_dbg(udc_dev(dum), "ep %p queue req %p to %s, len %d buf %p\n",
744 			ep, _req, _ep->name, _req->length, _req->buf);
745 #endif
746 	_req->status = -EINPROGRESS;
747 	_req->actual = 0;
748 	spin_lock_irqsave(&dum->lock, flags);
749 
750 	/* implement an emulated single-request FIFO */
751 	if (ep->desc && (ep->desc->bEndpointAddress & USB_DIR_IN) &&
752 			!dum->fifo_req_busy &&
753 			list_empty(&ep->queue) &&
754 			_req->length <= FIFO_SIZE) {
755 		req = &dum->fifo_req;
756 		dum->fifo_req_busy = 1;
757 		req->req = *_req;
758 		req->req.buf = dum->fifo_buf;
759 		memcpy(dum->fifo_buf, _req->buf, _req->length);
760 		req->req.context = dum;
761 		req->req.complete = fifo_complete;
762 
763 		list_add_tail(&req->queue, &ep->queue);
764 		++dum->callback_usage;
765 		spin_unlock(&dum->lock);
766 		_req->actual = _req->length;
767 		_req->status = 0;
768 		usb_gadget_giveback_request(_ep, _req);
769 		spin_lock(&dum->lock);
770 		--dum->callback_usage;
771 	}  else
772 		list_add_tail(&req->queue, &ep->queue);
773 	spin_unlock_irqrestore(&dum->lock, flags);
774 
775 	/* real hardware would likely enable transfers here, in case
776 	 * it'd been left NAKing.
777 	 */
778 	return 0;
779 }
780 
781 static int dummy_dequeue(struct usb_ep *_ep, struct usb_request *_req)
782 {
783 	struct dummy_ep		*ep;
784 	struct dummy		*dum;
785 	int			retval = -EINVAL;
786 	unsigned long		flags;
787 	struct dummy_request	*req = NULL, *iter;
788 
789 	if (!_ep || !_req)
790 		return retval;
791 	ep = usb_ep_to_dummy_ep(_ep);
792 	dum = ep_to_dummy(ep);
793 
794 	if (!dum->driver)
795 		return -ESHUTDOWN;
796 
797 	spin_lock_irqsave(&dum->lock, flags);
798 	list_for_each_entry(iter, &ep->queue, queue) {
799 		if (&iter->req != _req)
800 			continue;
801 		list_del_init(&iter->queue);
802 		_req->status = -ECONNRESET;
803 		req = iter;
804 		retval = 0;
805 		break;
806 	}
807 
808 	if (retval == 0) {
809 		dev_dbg(udc_dev(dum),
810 				"dequeued req %p from %s, len %d buf %p\n",
811 				req, _ep->name, _req->length, _req->buf);
812 		dummy_giveback(dum, _ep, req);
813 	}
814 	spin_unlock_irqrestore(&dum->lock, flags);
815 	return retval;
816 }
817 
818 static int
819 dummy_set_halt_and_wedge(struct usb_ep *_ep, int value, int wedged)
820 {
821 	struct dummy_ep		*ep;
822 	struct dummy		*dum;
823 
824 	if (!_ep)
825 		return -EINVAL;
826 	ep = usb_ep_to_dummy_ep(_ep);
827 	dum = ep_to_dummy(ep);
828 	if (!dum->driver)
829 		return -ESHUTDOWN;
830 	if (!value)
831 		ep->halted = ep->wedged = 0;
832 	else if (ep->desc && (ep->desc->bEndpointAddress & USB_DIR_IN) &&
833 			!list_empty(&ep->queue))
834 		return -EAGAIN;
835 	else {
836 		ep->halted = 1;
837 		if (wedged)
838 			ep->wedged = 1;
839 	}
840 	/* FIXME clear emulated data toggle too */
841 	return 0;
842 }
843 
844 static int
845 dummy_set_halt(struct usb_ep *_ep, int value)
846 {
847 	return dummy_set_halt_and_wedge(_ep, value, 0);
848 }
849 
850 static int dummy_set_wedge(struct usb_ep *_ep)
851 {
852 	if (!_ep || _ep->name == ep0name)
853 		return -EINVAL;
854 	return dummy_set_halt_and_wedge(_ep, 1, 1);
855 }
856 
857 static const struct usb_ep_ops dummy_ep_ops = {
858 	.enable		= dummy_enable,
859 	.disable	= dummy_disable,
860 
861 	.alloc_request	= dummy_alloc_request,
862 	.free_request	= dummy_free_request,
863 
864 	.queue		= dummy_queue,
865 	.dequeue	= dummy_dequeue,
866 
867 	.set_halt	= dummy_set_halt,
868 	.set_wedge	= dummy_set_wedge,
869 };
870 
871 /*-------------------------------------------------------------------------*/
872 
873 /* there are both host and device side versions of this call ... */
874 static int dummy_g_get_frame(struct usb_gadget *_gadget)
875 {
876 	struct timespec64 ts64;
877 
878 	ktime_get_ts64(&ts64);
879 	return ts64.tv_nsec / NSEC_PER_MSEC;
880 }
881 
882 static int dummy_wakeup(struct usb_gadget *_gadget)
883 {
884 	struct dummy_hcd *dum_hcd;
885 
886 	dum_hcd = gadget_to_dummy_hcd(_gadget);
887 	if (!(dum_hcd->dum->devstatus & ((1 << USB_DEVICE_B_HNP_ENABLE)
888 				| (1 << USB_DEVICE_REMOTE_WAKEUP))))
889 		return -EINVAL;
890 	if ((dum_hcd->port_status & USB_PORT_STAT_CONNECTION) == 0)
891 		return -ENOLINK;
892 	if ((dum_hcd->port_status & USB_PORT_STAT_SUSPEND) == 0 &&
893 			 dum_hcd->rh_state != DUMMY_RH_SUSPENDED)
894 		return -EIO;
895 
896 	/* FIXME: What if the root hub is suspended but the port isn't? */
897 
898 	/* hub notices our request, issues downstream resume, etc */
899 	dum_hcd->resuming = 1;
900 	dum_hcd->re_timeout = jiffies + msecs_to_jiffies(20);
901 	mod_timer(&dummy_hcd_to_hcd(dum_hcd)->rh_timer, dum_hcd->re_timeout);
902 	return 0;
903 }
904 
905 static int dummy_set_selfpowered(struct usb_gadget *_gadget, int value)
906 {
907 	struct dummy	*dum;
908 
909 	_gadget->is_selfpowered = (value != 0);
910 	dum = gadget_to_dummy_hcd(_gadget)->dum;
911 	if (value)
912 		dum->devstatus |= (1 << USB_DEVICE_SELF_POWERED);
913 	else
914 		dum->devstatus &= ~(1 << USB_DEVICE_SELF_POWERED);
915 	return 0;
916 }
917 
918 static void dummy_udc_update_ep0(struct dummy *dum)
919 {
920 	if (dum->gadget.speed == USB_SPEED_SUPER)
921 		dum->ep[0].ep.maxpacket = 9;
922 	else
923 		dum->ep[0].ep.maxpacket = 64;
924 }
925 
926 static int dummy_pullup(struct usb_gadget *_gadget, int value)
927 {
928 	struct dummy_hcd *dum_hcd;
929 	struct dummy	*dum;
930 	unsigned long	flags;
931 
932 	dum = gadget_dev_to_dummy(&_gadget->dev);
933 	dum_hcd = gadget_to_dummy_hcd(_gadget);
934 
935 	spin_lock_irqsave(&dum->lock, flags);
936 	dum->pullup = (value != 0);
937 	set_link_state(dum_hcd);
938 	spin_unlock_irqrestore(&dum->lock, flags);
939 
940 	usb_hcd_poll_rh_status(dummy_hcd_to_hcd(dum_hcd));
941 	return 0;
942 }
943 
944 static void dummy_udc_set_speed(struct usb_gadget *_gadget,
945 		enum usb_device_speed speed)
946 {
947 	struct dummy	*dum;
948 
949 	dum = gadget_dev_to_dummy(&_gadget->dev);
950 	dum->gadget.speed = speed;
951 	dummy_udc_update_ep0(dum);
952 }
953 
954 static void dummy_udc_async_callbacks(struct usb_gadget *_gadget, bool enable)
955 {
956 	struct dummy	*dum = gadget_dev_to_dummy(&_gadget->dev);
957 
958 	spin_lock_irq(&dum->lock);
959 	dum->ints_enabled = enable;
960 	if (!enable) {
961 		/*
962 		 * Emulate synchronize_irq(): wait for callbacks to finish.
963 		 * This has to happen after emulated interrupts are disabled
964 		 * (dum->ints_enabled is clear) and before the unbind callback,
965 		 * just like the call to synchronize_irq() in
966 		 * gadget/udc/core:gadget_unbind_driver().
967 		 */
968 		while (dum->callback_usage > 0) {
969 			spin_unlock_irq(&dum->lock);
970 			usleep_range(1000, 2000);
971 			spin_lock_irq(&dum->lock);
972 		}
973 	}
974 	spin_unlock_irq(&dum->lock);
975 }
976 
977 static int dummy_udc_start(struct usb_gadget *g,
978 		struct usb_gadget_driver *driver);
979 static int dummy_udc_stop(struct usb_gadget *g);
980 
981 static const struct usb_gadget_ops dummy_ops = {
982 	.get_frame	= dummy_g_get_frame,
983 	.wakeup		= dummy_wakeup,
984 	.set_selfpowered = dummy_set_selfpowered,
985 	.pullup		= dummy_pullup,
986 	.udc_start	= dummy_udc_start,
987 	.udc_stop	= dummy_udc_stop,
988 	.udc_set_speed	= dummy_udc_set_speed,
989 	.udc_async_callbacks = dummy_udc_async_callbacks,
990 };
991 
992 /*-------------------------------------------------------------------------*/
993 
994 /* "function" sysfs attribute */
995 static ssize_t function_show(struct device *dev, struct device_attribute *attr,
996 		char *buf)
997 {
998 	struct dummy	*dum = gadget_dev_to_dummy(dev);
999 
1000 	if (!dum->driver || !dum->driver->function)
1001 		return 0;
1002 	return scnprintf(buf, PAGE_SIZE, "%s\n", dum->driver->function);
1003 }
1004 static DEVICE_ATTR_RO(function);
1005 
1006 /*-------------------------------------------------------------------------*/
1007 
1008 /*
1009  * Driver registration/unregistration.
1010  *
1011  * This is basically hardware-specific; there's usually only one real USB
1012  * device (not host) controller since that's how USB devices are intended
1013  * to work.  So most implementations of these api calls will rely on the
1014  * fact that only one driver will ever bind to the hardware.  But curious
1015  * hardware can be built with discrete components, so the gadget API doesn't
1016  * require that assumption.
1017  *
1018  * For this emulator, it might be convenient to create a usb device
1019  * for each driver that registers:  just add to a big root hub.
1020  */
1021 
1022 static int dummy_udc_start(struct usb_gadget *g,
1023 		struct usb_gadget_driver *driver)
1024 {
1025 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(g);
1026 	struct dummy		*dum = dum_hcd->dum;
1027 
1028 	switch (g->speed) {
1029 	/* All the speeds we support */
1030 	case USB_SPEED_LOW:
1031 	case USB_SPEED_FULL:
1032 	case USB_SPEED_HIGH:
1033 	case USB_SPEED_SUPER:
1034 		break;
1035 	default:
1036 		dev_err(dummy_dev(dum_hcd), "Unsupported driver max speed %d\n",
1037 				driver->max_speed);
1038 		return -EINVAL;
1039 	}
1040 
1041 	/*
1042 	 * DEVICE side init ... the layer above hardware, which
1043 	 * can't enumerate without help from the driver we're binding.
1044 	 */
1045 
1046 	spin_lock_irq(&dum->lock);
1047 	dum->devstatus = 0;
1048 	dum->driver = driver;
1049 	spin_unlock_irq(&dum->lock);
1050 
1051 	return 0;
1052 }
1053 
1054 static int dummy_udc_stop(struct usb_gadget *g)
1055 {
1056 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(g);
1057 	struct dummy		*dum = dum_hcd->dum;
1058 
1059 	spin_lock_irq(&dum->lock);
1060 	dum->ints_enabled = 0;
1061 	stop_activity(dum);
1062 	dum->driver = NULL;
1063 	spin_unlock_irq(&dum->lock);
1064 
1065 	return 0;
1066 }
1067 
1068 #undef is_enabled
1069 
1070 /* The gadget structure is stored inside the hcd structure and will be
1071  * released along with it. */
1072 static void init_dummy_udc_hw(struct dummy *dum)
1073 {
1074 	int i;
1075 
1076 	INIT_LIST_HEAD(&dum->gadget.ep_list);
1077 	for (i = 0; i < DUMMY_ENDPOINTS; i++) {
1078 		struct dummy_ep	*ep = &dum->ep[i];
1079 
1080 		if (!ep_info[i].name)
1081 			break;
1082 		ep->ep.name = ep_info[i].name;
1083 		ep->ep.caps = ep_info[i].caps;
1084 		ep->ep.ops = &dummy_ep_ops;
1085 		list_add_tail(&ep->ep.ep_list, &dum->gadget.ep_list);
1086 		ep->halted = ep->wedged = ep->already_seen =
1087 				ep->setup_stage = 0;
1088 		usb_ep_set_maxpacket_limit(&ep->ep, ~0);
1089 		ep->ep.max_streams = 16;
1090 		ep->last_io = jiffies;
1091 		ep->gadget = &dum->gadget;
1092 		ep->desc = NULL;
1093 		INIT_LIST_HEAD(&ep->queue);
1094 	}
1095 
1096 	dum->gadget.ep0 = &dum->ep[0].ep;
1097 	list_del_init(&dum->ep[0].ep.ep_list);
1098 	INIT_LIST_HEAD(&dum->fifo_req.queue);
1099 
1100 #ifdef CONFIG_USB_OTG
1101 	dum->gadget.is_otg = 1;
1102 #endif
1103 }
1104 
1105 static int dummy_udc_probe(struct platform_device *pdev)
1106 {
1107 	struct dummy	*dum;
1108 	int		rc;
1109 
1110 	dum = *((void **)dev_get_platdata(&pdev->dev));
1111 	/* Clear usb_gadget region for new registration to udc-core */
1112 	memzero_explicit(&dum->gadget, sizeof(struct usb_gadget));
1113 	dum->gadget.name = gadget_name;
1114 	dum->gadget.ops = &dummy_ops;
1115 	if (mod_data.is_super_speed)
1116 		dum->gadget.max_speed = USB_SPEED_SUPER;
1117 	else if (mod_data.is_high_speed)
1118 		dum->gadget.max_speed = USB_SPEED_HIGH;
1119 	else
1120 		dum->gadget.max_speed = USB_SPEED_FULL;
1121 
1122 	dum->gadget.dev.parent = &pdev->dev;
1123 	init_dummy_udc_hw(dum);
1124 
1125 	rc = usb_add_gadget_udc(&pdev->dev, &dum->gadget);
1126 	if (rc < 0)
1127 		goto err_udc;
1128 
1129 	rc = device_create_file(&dum->gadget.dev, &dev_attr_function);
1130 	if (rc < 0)
1131 		goto err_dev;
1132 	platform_set_drvdata(pdev, dum);
1133 	return rc;
1134 
1135 err_dev:
1136 	usb_del_gadget_udc(&dum->gadget);
1137 err_udc:
1138 	return rc;
1139 }
1140 
1141 static void dummy_udc_remove(struct platform_device *pdev)
1142 {
1143 	struct dummy	*dum = platform_get_drvdata(pdev);
1144 
1145 	device_remove_file(&dum->gadget.dev, &dev_attr_function);
1146 	usb_del_gadget_udc(&dum->gadget);
1147 }
1148 
1149 static void dummy_udc_pm(struct dummy *dum, struct dummy_hcd *dum_hcd,
1150 		int suspend)
1151 {
1152 	spin_lock_irq(&dum->lock);
1153 	dum->udc_suspended = suspend;
1154 	set_link_state(dum_hcd);
1155 	spin_unlock_irq(&dum->lock);
1156 }
1157 
1158 static int dummy_udc_suspend(struct platform_device *pdev, pm_message_t state)
1159 {
1160 	struct dummy		*dum = platform_get_drvdata(pdev);
1161 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
1162 
1163 	dev_dbg(&pdev->dev, "%s\n", __func__);
1164 	dummy_udc_pm(dum, dum_hcd, 1);
1165 	usb_hcd_poll_rh_status(dummy_hcd_to_hcd(dum_hcd));
1166 	return 0;
1167 }
1168 
1169 static int dummy_udc_resume(struct platform_device *pdev)
1170 {
1171 	struct dummy		*dum = platform_get_drvdata(pdev);
1172 	struct dummy_hcd	*dum_hcd = gadget_to_dummy_hcd(&dum->gadget);
1173 
1174 	dev_dbg(&pdev->dev, "%s\n", __func__);
1175 	dummy_udc_pm(dum, dum_hcd, 0);
1176 	usb_hcd_poll_rh_status(dummy_hcd_to_hcd(dum_hcd));
1177 	return 0;
1178 }
1179 
1180 static struct platform_driver dummy_udc_driver = {
1181 	.probe		= dummy_udc_probe,
1182 	.remove		= dummy_udc_remove,
1183 	.suspend	= dummy_udc_suspend,
1184 	.resume		= dummy_udc_resume,
1185 	.driver		= {
1186 		.name	= gadget_name,
1187 	},
1188 };
1189 
1190 /*-------------------------------------------------------------------------*/
1191 
1192 static unsigned int dummy_get_ep_idx(const struct usb_endpoint_descriptor *desc)
1193 {
1194 	unsigned int index;
1195 
1196 	index = usb_endpoint_num(desc) << 1;
1197 	if (usb_endpoint_dir_in(desc))
1198 		index |= 1;
1199 	return index;
1200 }
1201 
1202 /* HOST SIDE DRIVER
1203  *
1204  * this uses the hcd framework to hook up to host side drivers.
1205  * its root hub will only have one device, otherwise it acts like
1206  * a normal host controller.
1207  *
1208  * when urbs are queued, they're just stuck on a list that we
1209  * scan in a timer callback.  that callback connects writes from
1210  * the host with reads from the device, and so on, based on the
1211  * usb 2.0 rules.
1212  */
1213 
1214 static int dummy_ep_stream_en(struct dummy_hcd *dum_hcd, struct urb *urb)
1215 {
1216 	const struct usb_endpoint_descriptor *desc = &urb->ep->desc;
1217 	u32 index;
1218 
1219 	if (!usb_endpoint_xfer_bulk(desc))
1220 		return 0;
1221 
1222 	index = dummy_get_ep_idx(desc);
1223 	return (1 << index) & dum_hcd->stream_en_ep;
1224 }
1225 
1226 /*
1227  * The max stream number is saved as a nibble so for the 30 possible endpoints
1228  * we only 15 bytes of memory. Therefore we are limited to max 16 streams (0
1229  * means we use only 1 stream). The maximum according to the spec is 16bit so
1230  * if the 16 stream limit is about to go, the array size should be incremented
1231  * to 30 elements of type u16.
1232  */
1233 static int get_max_streams_for_pipe(struct dummy_hcd *dum_hcd,
1234 		unsigned int pipe)
1235 {
1236 	int max_streams;
1237 
1238 	max_streams = dum_hcd->num_stream[usb_pipeendpoint(pipe)];
1239 	if (usb_pipeout(pipe))
1240 		max_streams >>= 4;
1241 	else
1242 		max_streams &= 0xf;
1243 	max_streams++;
1244 	return max_streams;
1245 }
1246 
1247 static void set_max_streams_for_pipe(struct dummy_hcd *dum_hcd,
1248 		unsigned int pipe, unsigned int streams)
1249 {
1250 	int max_streams;
1251 
1252 	streams--;
1253 	max_streams = dum_hcd->num_stream[usb_pipeendpoint(pipe)];
1254 	if (usb_pipeout(pipe)) {
1255 		streams <<= 4;
1256 		max_streams &= 0xf;
1257 	} else {
1258 		max_streams &= 0xf0;
1259 	}
1260 	max_streams |= streams;
1261 	dum_hcd->num_stream[usb_pipeendpoint(pipe)] = max_streams;
1262 }
1263 
1264 static int dummy_validate_stream(struct dummy_hcd *dum_hcd, struct urb *urb)
1265 {
1266 	unsigned int max_streams;
1267 	int enabled;
1268 
1269 	enabled = dummy_ep_stream_en(dum_hcd, urb);
1270 	if (!urb->stream_id) {
1271 		if (enabled)
1272 			return -EINVAL;
1273 		return 0;
1274 	}
1275 	if (!enabled)
1276 		return -EINVAL;
1277 
1278 	max_streams = get_max_streams_for_pipe(dum_hcd,
1279 			usb_pipeendpoint(urb->pipe));
1280 	if (urb->stream_id > max_streams) {
1281 		dev_err(dummy_dev(dum_hcd), "Stream id %d is out of range.\n",
1282 				urb->stream_id);
1283 		BUG();
1284 		return -EINVAL;
1285 	}
1286 	return 0;
1287 }
1288 
1289 static int dummy_urb_enqueue(
1290 	struct usb_hcd			*hcd,
1291 	struct urb			*urb,
1292 	gfp_t				mem_flags
1293 ) {
1294 	struct dummy_hcd *dum_hcd;
1295 	struct urbp	*urbp;
1296 	unsigned long	flags;
1297 	int		rc;
1298 
1299 	urbp = kmalloc_obj(*urbp, mem_flags);
1300 	if (!urbp)
1301 		return -ENOMEM;
1302 	urbp->urb = urb;
1303 	urbp->miter_started = 0;
1304 
1305 	dum_hcd = hcd_to_dummy_hcd(hcd);
1306 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
1307 
1308 	rc = dummy_validate_stream(dum_hcd, urb);
1309 	if (rc) {
1310 		kfree(urbp);
1311 		goto done;
1312 	}
1313 
1314 	rc = usb_hcd_link_urb_to_ep(hcd, urb);
1315 	if (rc) {
1316 		kfree(urbp);
1317 		goto done;
1318 	}
1319 
1320 	if (!dum_hcd->udev) {
1321 		dum_hcd->udev = urb->dev;
1322 		usb_get_dev(dum_hcd->udev);
1323 	} else if (unlikely(dum_hcd->udev != urb->dev))
1324 		dev_err(dummy_dev(dum_hcd), "usb_device address has changed!\n");
1325 
1326 	list_add_tail(&urbp->urbp_list, &dum_hcd->urbp_list);
1327 	urb->hcpriv = urbp;
1328 	if (!dum_hcd->next_frame_urbp)
1329 		dum_hcd->next_frame_urbp = urbp;
1330 	if (usb_pipetype(urb->pipe) == PIPE_CONTROL)
1331 		urb->error_count = 1;		/* mark as a new urb */
1332 
1333 	/* kick the scheduler, it'll do the rest */
1334 	if (!dum_hcd->timer_pending) {
1335 		dum_hcd->timer_pending = 1;
1336 		hrtimer_start(&dum_hcd->timer, ns_to_ktime(DUMMY_TIMER_INT_NSECS),
1337 				HRTIMER_MODE_REL_SOFT);
1338 	}
1339 
1340  done:
1341 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
1342 	return rc;
1343 }
1344 
1345 static int dummy_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
1346 {
1347 	struct dummy_hcd *dum_hcd;
1348 	unsigned long	flags;
1349 	int		rc;
1350 
1351 	/* giveback happens automatically in timer callback,
1352 	 * so make sure the callback happens */
1353 	dum_hcd = hcd_to_dummy_hcd(hcd);
1354 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
1355 
1356 	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
1357 	if (rc == 0 && !dum_hcd->timer_pending) {
1358 		dum_hcd->timer_pending = 1;
1359 		hrtimer_start(&dum_hcd->timer, ns_to_ktime(0), HRTIMER_MODE_REL_SOFT);
1360 	}
1361 
1362 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
1363 	return rc;
1364 }
1365 
1366 static int dummy_perform_transfer(struct urb *urb, struct dummy_request *req,
1367 		u32 len)
1368 {
1369 	void *ubuf, *rbuf;
1370 	struct urbp *urbp = urb->hcpriv;
1371 	int to_host;
1372 	struct sg_mapping_iter *miter = &urbp->miter;
1373 	u32 trans = 0;
1374 	u32 this_sg;
1375 	bool next_sg;
1376 
1377 	to_host = usb_urb_dir_in(urb);
1378 	rbuf = req->req.buf + req->req.actual;
1379 
1380 	if (!urb->num_sgs) {
1381 		ubuf = urb->transfer_buffer + urb->actual_length;
1382 		if (to_host)
1383 			memcpy(ubuf, rbuf, len);
1384 		else
1385 			memcpy(rbuf, ubuf, len);
1386 		return len;
1387 	}
1388 
1389 	if (!urbp->miter_started) {
1390 		u32 flags = SG_MITER_ATOMIC;
1391 
1392 		if (to_host)
1393 			flags |= SG_MITER_TO_SG;
1394 		else
1395 			flags |= SG_MITER_FROM_SG;
1396 
1397 		sg_miter_start(miter, urb->sg, urb->num_sgs, flags);
1398 		urbp->miter_started = 1;
1399 	}
1400 	next_sg = sg_miter_next(miter);
1401 	if (next_sg == false) {
1402 		WARN_ON_ONCE(1);
1403 		return -EINVAL;
1404 	}
1405 	do {
1406 		ubuf = miter->addr;
1407 		this_sg = min_t(u32, len, miter->length);
1408 		miter->consumed = this_sg;
1409 		trans += this_sg;
1410 
1411 		if (to_host)
1412 			memcpy(ubuf, rbuf, this_sg);
1413 		else
1414 			memcpy(rbuf, ubuf, this_sg);
1415 		len -= this_sg;
1416 
1417 		if (!len)
1418 			break;
1419 		next_sg = sg_miter_next(miter);
1420 		if (next_sg == false) {
1421 			WARN_ON_ONCE(1);
1422 			return -EINVAL;
1423 		}
1424 
1425 		rbuf += this_sg;
1426 	} while (1);
1427 
1428 	sg_miter_stop(miter);
1429 	return trans;
1430 }
1431 
1432 /* transfer up to a frame's worth; caller must own lock */
1433 static int transfer(struct dummy_hcd *dum_hcd, struct urb *urb,
1434 		struct dummy_ep *ep, int limit, int *status)
1435 {
1436 	struct dummy		*dum = dum_hcd->dum;
1437 	struct dummy_request	*req;
1438 	int			sent = 0;
1439 
1440 top:
1441 	/* if there's no request queued, the device is NAKing; return */
1442 	list_for_each_entry(req, &ep->queue, queue) {
1443 		unsigned	host_len, dev_len, len;
1444 		int		is_short, to_host;
1445 		int		rescan = 0;
1446 
1447 		if (dummy_ep_stream_en(dum_hcd, urb)) {
1448 			if ((urb->stream_id != req->req.stream_id))
1449 				continue;
1450 		}
1451 
1452 		/* 1..N packets of ep->ep.maxpacket each ... the last one
1453 		 * may be short (including zero length).
1454 		 *
1455 		 * writer can send a zlp explicitly (length 0) or implicitly
1456 		 * (length mod maxpacket zero, and 'zero' flag); they always
1457 		 * terminate reads.
1458 		 */
1459 		host_len = urb->transfer_buffer_length - urb->actual_length;
1460 		dev_len = req->req.length - req->req.actual;
1461 		len = min(host_len, dev_len);
1462 
1463 		/* FIXME update emulated data toggle too */
1464 
1465 		to_host = usb_urb_dir_in(urb);
1466 		if (unlikely(len == 0))
1467 			is_short = 1;
1468 		else {
1469 			/* not enough bandwidth left? */
1470 			if (limit < ep->ep.maxpacket && limit < len)
1471 				break;
1472 			len = min_t(unsigned, len, limit);
1473 			if (len == 0)
1474 				break;
1475 
1476 			/* send multiple of maxpacket first, then remainder */
1477 			if (len >= ep->ep.maxpacket) {
1478 				is_short = 0;
1479 				if (len % ep->ep.maxpacket)
1480 					rescan = 1;
1481 				len -= len % ep->ep.maxpacket;
1482 			} else {
1483 				is_short = 1;
1484 			}
1485 
1486 			len = dummy_perform_transfer(urb, req, len);
1487 
1488 			ep->last_io = jiffies;
1489 			if ((int)len < 0) {
1490 				req->req.status = len;
1491 			} else {
1492 				limit -= len;
1493 				sent += len;
1494 				urb->actual_length += len;
1495 				req->req.actual += len;
1496 			}
1497 		}
1498 
1499 		/* short packets terminate, maybe with overflow/underflow.
1500 		 * it's only really an error to write too much.
1501 		 *
1502 		 * partially filling a buffer optionally blocks queue advances
1503 		 * (so completion handlers can clean up the queue) but we don't
1504 		 * need to emulate such data-in-flight.
1505 		 */
1506 		if (is_short) {
1507 			if (host_len == dev_len) {
1508 				req->req.status = 0;
1509 				*status = 0;
1510 			} else if (to_host) {
1511 				req->req.status = 0;
1512 				if (dev_len > host_len)
1513 					*status = -EOVERFLOW;
1514 				else
1515 					*status = 0;
1516 			} else {
1517 				*status = 0;
1518 				if (host_len > dev_len)
1519 					req->req.status = -EOVERFLOW;
1520 				else
1521 					req->req.status = 0;
1522 			}
1523 
1524 		/*
1525 		 * many requests terminate without a short packet.
1526 		 * send a zlp if demanded by flags.
1527 		 */
1528 		} else {
1529 			if (req->req.length == req->req.actual) {
1530 				if (req->req.zero && to_host)
1531 					rescan = 1;
1532 				else
1533 					req->req.status = 0;
1534 			}
1535 			if (urb->transfer_buffer_length == urb->actual_length) {
1536 				if (urb->transfer_flags & URB_ZERO_PACKET &&
1537 				    !to_host)
1538 					rescan = 1;
1539 				else
1540 					*status = 0;
1541 			}
1542 		}
1543 
1544 		/* device side completion --> continuable */
1545 		if (req->req.status != -EINPROGRESS) {
1546 			list_del_init(&req->queue);
1547 
1548 			dummy_giveback(dum, &ep->ep, req);
1549 
1550 			/* requests might have been unlinked... */
1551 			rescan = 1;
1552 		}
1553 
1554 		/* host side completion --> terminate */
1555 		if (*status != -EINPROGRESS)
1556 			break;
1557 
1558 		/* rescan to continue with any other queued i/o */
1559 		if (rescan)
1560 			goto top;
1561 
1562 		/* request not fully transferred; stop iterating to
1563 		 * preserve data ordering across queued requests.
1564 		 */
1565 		if (req->req.actual < req->req.length)
1566 			break;
1567 	}
1568 	return sent;
1569 }
1570 
1571 static int periodic_bytes(struct dummy *dum, struct dummy_ep *ep)
1572 {
1573 	int	limit = ep->ep.maxpacket;
1574 
1575 	if (dum->gadget.speed == USB_SPEED_HIGH) {
1576 		int	tmp;
1577 
1578 		/* high bandwidth mode */
1579 		tmp = usb_endpoint_maxp_mult(ep->desc);
1580 		tmp *= 8 /* applies to entire frame */;
1581 		limit += limit * tmp;
1582 	}
1583 	if (dum->gadget.speed == USB_SPEED_SUPER) {
1584 		switch (usb_endpoint_type(ep->desc)) {
1585 		case USB_ENDPOINT_XFER_ISOC:
1586 			/* Sec. 4.4.8.2 USB3.0 Spec */
1587 			limit = 3 * 16 * 1024 * 8;
1588 			break;
1589 		case USB_ENDPOINT_XFER_INT:
1590 			/* Sec. 4.4.7.2 USB3.0 Spec */
1591 			limit = 3 * 1024 * 8;
1592 			break;
1593 		case USB_ENDPOINT_XFER_BULK:
1594 		default:
1595 			break;
1596 		}
1597 	}
1598 	return limit;
1599 }
1600 
1601 #define is_active(dum_hcd)	((dum_hcd->port_status & \
1602 		(USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE | \
1603 			USB_PORT_STAT_SUSPEND)) \
1604 		== (USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE))
1605 
1606 static struct dummy_ep *find_endpoint(struct dummy *dum, u8 address)
1607 {
1608 	int		i;
1609 
1610 	if (!is_active((dum->gadget.speed == USB_SPEED_SUPER ?
1611 			dum->ss_hcd : dum->hs_hcd)))
1612 		return NULL;
1613 	if (!dum->ints_enabled)
1614 		return NULL;
1615 	if ((address & ~USB_DIR_IN) == 0)
1616 		return &dum->ep[0];
1617 	for (i = 1; i < DUMMY_ENDPOINTS; i++) {
1618 		struct dummy_ep	*ep = &dum->ep[i];
1619 
1620 		if (!ep->desc)
1621 			continue;
1622 		if (ep->desc->bEndpointAddress == address)
1623 			return ep;
1624 	}
1625 	return NULL;
1626 }
1627 
1628 #undef is_active
1629 
1630 #define Dev_Request	(USB_TYPE_STANDARD | USB_RECIP_DEVICE)
1631 #define Dev_InRequest	(Dev_Request | USB_DIR_IN)
1632 #define Intf_Request	(USB_TYPE_STANDARD | USB_RECIP_INTERFACE)
1633 #define Intf_InRequest	(Intf_Request | USB_DIR_IN)
1634 #define Ep_Request	(USB_TYPE_STANDARD | USB_RECIP_ENDPOINT)
1635 #define Ep_InRequest	(Ep_Request | USB_DIR_IN)
1636 
1637 
1638 /**
1639  * handle_control_request() - handles all control transfers
1640  * @dum_hcd: pointer to dummy (the_controller)
1641  * @urb: the urb request to handle
1642  * @setup: pointer to the setup data for a USB device control
1643  *	 request
1644  * @status: pointer to request handling status
1645  *
1646  * Return 0 - if the request was handled
1647  *	  1 - if the request wasn't handles
1648  *	  error code on error
1649  */
1650 static int handle_control_request(struct dummy_hcd *dum_hcd, struct urb *urb,
1651 				  struct usb_ctrlrequest *setup,
1652 				  int *status)
1653 {
1654 	struct dummy_ep		*ep2;
1655 	struct dummy		*dum = dum_hcd->dum;
1656 	int			ret_val = 1;
1657 	unsigned	w_index;
1658 	unsigned	w_value;
1659 
1660 	w_index = le16_to_cpu(setup->wIndex);
1661 	w_value = le16_to_cpu(setup->wValue);
1662 	switch (setup->bRequest) {
1663 	case USB_REQ_SET_ADDRESS:
1664 		if (setup->bRequestType != Dev_Request)
1665 			break;
1666 		dum->address = w_value;
1667 		*status = 0;
1668 		dev_dbg(udc_dev(dum), "set_address = %d\n",
1669 				w_value);
1670 		ret_val = 0;
1671 		break;
1672 	case USB_REQ_SET_FEATURE:
1673 		if (setup->bRequestType == Dev_Request) {
1674 			ret_val = 0;
1675 			switch (w_value) {
1676 			case USB_DEVICE_REMOTE_WAKEUP:
1677 				break;
1678 			case USB_DEVICE_B_HNP_ENABLE:
1679 				dum->gadget.b_hnp_enable = 1;
1680 				break;
1681 			case USB_DEVICE_A_HNP_SUPPORT:
1682 				dum->gadget.a_hnp_support = 1;
1683 				break;
1684 			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1685 				dum->gadget.a_alt_hnp_support = 1;
1686 				break;
1687 			case USB_DEVICE_U1_ENABLE:
1688 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1689 				    HCD_USB3)
1690 					w_value = USB_DEV_STAT_U1_ENABLED;
1691 				else
1692 					ret_val = -EOPNOTSUPP;
1693 				break;
1694 			case USB_DEVICE_U2_ENABLE:
1695 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1696 				    HCD_USB3)
1697 					w_value = USB_DEV_STAT_U2_ENABLED;
1698 				else
1699 					ret_val = -EOPNOTSUPP;
1700 				break;
1701 			case USB_DEVICE_LTM_ENABLE:
1702 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1703 				    HCD_USB3)
1704 					w_value = USB_DEV_STAT_LTM_ENABLED;
1705 				else
1706 					ret_val = -EOPNOTSUPP;
1707 				break;
1708 			default:
1709 				ret_val = -EOPNOTSUPP;
1710 			}
1711 			if (ret_val == 0) {
1712 				dum->devstatus |= (1 << w_value);
1713 				*status = 0;
1714 			}
1715 		} else if (setup->bRequestType == Ep_Request) {
1716 			/* endpoint halt */
1717 			ep2 = find_endpoint(dum, w_index);
1718 			if (!ep2 || ep2->ep.name == ep0name) {
1719 				ret_val = -EOPNOTSUPP;
1720 				break;
1721 			}
1722 			ep2->halted = 1;
1723 			ret_val = 0;
1724 			*status = 0;
1725 		}
1726 		break;
1727 	case USB_REQ_CLEAR_FEATURE:
1728 		if (setup->bRequestType == Dev_Request) {
1729 			ret_val = 0;
1730 			switch (w_value) {
1731 			case USB_DEVICE_REMOTE_WAKEUP:
1732 				w_value = USB_DEVICE_REMOTE_WAKEUP;
1733 				break;
1734 			case USB_DEVICE_U1_ENABLE:
1735 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1736 				    HCD_USB3)
1737 					w_value = USB_DEV_STAT_U1_ENABLED;
1738 				else
1739 					ret_val = -EOPNOTSUPP;
1740 				break;
1741 			case USB_DEVICE_U2_ENABLE:
1742 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1743 				    HCD_USB3)
1744 					w_value = USB_DEV_STAT_U2_ENABLED;
1745 				else
1746 					ret_val = -EOPNOTSUPP;
1747 				break;
1748 			case USB_DEVICE_LTM_ENABLE:
1749 				if (dummy_hcd_to_hcd(dum_hcd)->speed ==
1750 				    HCD_USB3)
1751 					w_value = USB_DEV_STAT_LTM_ENABLED;
1752 				else
1753 					ret_val = -EOPNOTSUPP;
1754 				break;
1755 			default:
1756 				ret_val = -EOPNOTSUPP;
1757 				break;
1758 			}
1759 			if (ret_val == 0) {
1760 				dum->devstatus &= ~(1 << w_value);
1761 				*status = 0;
1762 			}
1763 		} else if (setup->bRequestType == Ep_Request) {
1764 			/* endpoint halt */
1765 			ep2 = find_endpoint(dum, w_index);
1766 			if (!ep2) {
1767 				ret_val = -EOPNOTSUPP;
1768 				break;
1769 			}
1770 			if (!ep2->wedged)
1771 				ep2->halted = 0;
1772 			ret_val = 0;
1773 			*status = 0;
1774 		}
1775 		break;
1776 	case USB_REQ_GET_STATUS:
1777 		if (setup->bRequestType == Dev_InRequest
1778 				|| setup->bRequestType == Intf_InRequest
1779 				|| setup->bRequestType == Ep_InRequest) {
1780 			char *buf;
1781 			/*
1782 			 * device: remote wakeup, selfpowered
1783 			 * interface: nothing
1784 			 * endpoint: halt
1785 			 */
1786 			buf = (char *)urb->transfer_buffer;
1787 			if (urb->transfer_buffer_length > 0) {
1788 				if (setup->bRequestType == Ep_InRequest) {
1789 					ep2 = find_endpoint(dum, w_index);
1790 					if (!ep2) {
1791 						ret_val = -EOPNOTSUPP;
1792 						break;
1793 					}
1794 					buf[0] = ep2->halted;
1795 				} else if (setup->bRequestType ==
1796 					   Dev_InRequest) {
1797 					buf[0] = (u8)dum->devstatus;
1798 				} else
1799 					buf[0] = 0;
1800 			}
1801 			if (urb->transfer_buffer_length > 1)
1802 				buf[1] = 0;
1803 			urb->actual_length = min_t(u32, 2,
1804 				urb->transfer_buffer_length);
1805 			ret_val = 0;
1806 			*status = 0;
1807 		}
1808 		break;
1809 	}
1810 	return ret_val;
1811 }
1812 
1813 /*
1814  * Drive both sides of the transfers; looks like irq handlers to both
1815  * drivers except that the callbacks are invoked from soft interrupt
1816  * context.
1817  */
1818 static enum hrtimer_restart dummy_timer(struct hrtimer *t)
1819 {
1820 	struct dummy_hcd	*dum_hcd = timer_container_of(dum_hcd, t,
1821 							      timer);
1822 	struct dummy		*dum = dum_hcd->dum;
1823 	struct urbp		*urbp, *tmp;
1824 	unsigned long		flags;
1825 	int			limit, total;
1826 	int			i;
1827 
1828 	/* simplistic model for one frame's bandwidth */
1829 	/* FIXME: account for transaction and packet overhead */
1830 	switch (dum->gadget.speed) {
1831 	case USB_SPEED_LOW:
1832 		total = 8/*bytes*/ * 12/*packets*/;
1833 		break;
1834 	case USB_SPEED_FULL:
1835 		total = 64/*bytes*/ * 19/*packets*/;
1836 		break;
1837 	case USB_SPEED_HIGH:
1838 		total = 512/*bytes*/ * 13/*packets*/ * 8/*uframes*/;
1839 		break;
1840 	case USB_SPEED_SUPER:
1841 		/* Bus speed is 500000 bytes/ms, so use a little less */
1842 		total = 490000;
1843 		break;
1844 	default:	/* Can't happen */
1845 		dev_err(dummy_dev(dum_hcd), "bogus device speed\n");
1846 		total = 0;
1847 		break;
1848 	}
1849 
1850 	/* look at each urb queued by the host side driver */
1851 	spin_lock_irqsave(&dum->lock, flags);
1852 	dum_hcd->timer_pending = 0;
1853 
1854 	if (!dum_hcd->udev) {
1855 		dev_err(dummy_dev(dum_hcd),
1856 				"timer fired with no URBs pending?\n");
1857 		spin_unlock_irqrestore(&dum->lock, flags);
1858 		return HRTIMER_NORESTART;
1859 	}
1860 	dum_hcd->next_frame_urbp = NULL;
1861 
1862 	for (i = 0; i < DUMMY_ENDPOINTS; i++) {
1863 		if (!ep_info[i].name)
1864 			break;
1865 		dum->ep[i].already_seen = 0;
1866 	}
1867 
1868 restart:
1869 	list_for_each_entry_safe(urbp, tmp, &dum_hcd->urbp_list, urbp_list) {
1870 		struct urb		*urb;
1871 		struct dummy_request	*req;
1872 		u8			address;
1873 		struct dummy_ep		*ep = NULL;
1874 		int			status = -EINPROGRESS;
1875 
1876 		/* stop when we reach URBs queued after the timer interrupt */
1877 		if (urbp == dum_hcd->next_frame_urbp)
1878 			break;
1879 
1880 		urb = urbp->urb;
1881 		if (urb->unlinked)
1882 			goto return_urb;
1883 		else if (dum_hcd->rh_state != DUMMY_RH_RUNNING)
1884 			continue;
1885 
1886 		/* Used up this frame's bandwidth? */
1887 		if (total <= 0)
1888 			continue;
1889 
1890 		/* find the gadget's ep for this request (if configured) */
1891 		address = usb_pipeendpoint (urb->pipe);
1892 		if (usb_urb_dir_in(urb))
1893 			address |= USB_DIR_IN;
1894 		ep = find_endpoint(dum, address);
1895 		if (!ep) {
1896 			/* set_configuration() disagreement */
1897 			dev_dbg(dummy_dev(dum_hcd),
1898 				"no ep configured for urb %p\n",
1899 				urb);
1900 			status = -EPROTO;
1901 			goto return_urb;
1902 		}
1903 
1904 		if (ep->already_seen)
1905 			continue;
1906 		ep->already_seen = 1;
1907 		if (ep == &dum->ep[0] && urb->error_count) {
1908 			ep->setup_stage = 1;	/* a new urb */
1909 			urb->error_count = 0;
1910 		}
1911 		if (ep->halted && !ep->setup_stage) {
1912 			/* NOTE: must not be iso! */
1913 			dev_dbg(dummy_dev(dum_hcd), "ep %s halted, urb %p\n",
1914 					ep->ep.name, urb);
1915 			status = -EPIPE;
1916 			goto return_urb;
1917 		}
1918 		/* FIXME make sure both ends agree on maxpacket */
1919 
1920 		/* handle control requests */
1921 		if (ep == &dum->ep[0] && ep->setup_stage) {
1922 			struct usb_ctrlrequest		setup;
1923 			int				value;
1924 
1925 			setup = *(struct usb_ctrlrequest *) urb->setup_packet;
1926 			/* paranoia, in case of stale queued data */
1927 			list_for_each_entry(req, &ep->queue, queue) {
1928 				list_del_init(&req->queue);
1929 				req->req.status = -EOVERFLOW;
1930 				dev_dbg(udc_dev(dum), "stale req = %p\n",
1931 						req);
1932 
1933 				dummy_giveback(dum, &ep->ep, req);
1934 				ep->already_seen = 0;
1935 				goto restart;
1936 			}
1937 
1938 			/* gadget driver never sees set_address or operations
1939 			 * on standard feature flags.  some hardware doesn't
1940 			 * even expose them.
1941 			 */
1942 			ep->last_io = jiffies;
1943 			ep->setup_stage = 0;
1944 			ep->halted = 0;
1945 
1946 			value = handle_control_request(dum_hcd, urb, &setup,
1947 						       &status);
1948 
1949 			/* gadget driver handles all other requests.  block
1950 			 * until setup() returns; no reentrancy issues etc.
1951 			 */
1952 			if (value > 0) {
1953 				++dum->callback_usage;
1954 				spin_unlock(&dum->lock);
1955 				value = dum->driver->setup(&dum->gadget,
1956 						&setup);
1957 				spin_lock(&dum->lock);
1958 				--dum->callback_usage;
1959 
1960 				if (value >= 0) {
1961 					/* no delays (max 64KB data stage) */
1962 					limit = 64*1024;
1963 					goto treat_control_like_bulk;
1964 				}
1965 				/* error, see below */
1966 			}
1967 
1968 			if (value < 0) {
1969 				if (value != -EOPNOTSUPP)
1970 					dev_dbg(udc_dev(dum),
1971 						"setup --> %d\n",
1972 						value);
1973 				status = -EPIPE;
1974 				urb->actual_length = 0;
1975 			}
1976 
1977 			goto return_urb;
1978 		}
1979 
1980 		/* non-control requests */
1981 		limit = total;
1982 		switch (usb_pipetype(urb->pipe)) {
1983 		case PIPE_ISOCHRONOUS:
1984 			/*
1985 			 * We don't support isochronous.  But if we did,
1986 			 * here are some of the issues we'd have to face:
1987 			 *
1988 			 * Is it urb->interval since the last xfer?
1989 			 * Use urb->iso_frame_desc[i].
1990 			 * Complete whether or not ep has requests queued.
1991 			 * Report random errors, to debug drivers.
1992 			 */
1993 			limit = max(limit, periodic_bytes(dum, ep));
1994 			status = -EINVAL;	/* fail all xfers */
1995 			break;
1996 
1997 		case PIPE_INTERRUPT:
1998 			/* FIXME is it urb->interval since the last xfer?
1999 			 * this almost certainly polls too fast.
2000 			 */
2001 			limit = max(limit, periodic_bytes(dum, ep));
2002 			fallthrough;
2003 
2004 		default:
2005 treat_control_like_bulk:
2006 			ep->last_io = jiffies;
2007 			total -= transfer(dum_hcd, urb, ep, limit, &status);
2008 			break;
2009 		}
2010 
2011 		/* incomplete transfer? */
2012 		if (status == -EINPROGRESS)
2013 			continue;
2014 
2015 return_urb:
2016 		list_del(&urbp->urbp_list);
2017 		kfree(urbp);
2018 		if (ep)
2019 			ep->already_seen = ep->setup_stage = 0;
2020 
2021 		usb_hcd_unlink_urb_from_ep(dummy_hcd_to_hcd(dum_hcd), urb);
2022 		spin_unlock(&dum->lock);
2023 		usb_hcd_giveback_urb(dummy_hcd_to_hcd(dum_hcd), urb, status);
2024 		spin_lock(&dum->lock);
2025 
2026 		goto restart;
2027 	}
2028 
2029 	if (list_empty(&dum_hcd->urbp_list)) {
2030 		usb_put_dev(dum_hcd->udev);
2031 		dum_hcd->udev = NULL;
2032 	} else if (!dum_hcd->timer_pending &&
2033 			dum_hcd->rh_state == DUMMY_RH_RUNNING) {
2034 		/* want a 1 msec delay here */
2035 		dum_hcd->timer_pending = 1;
2036 		hrtimer_start(&dum_hcd->timer, ns_to_ktime(DUMMY_TIMER_INT_NSECS),
2037 				HRTIMER_MODE_REL_SOFT);
2038 	}
2039 
2040 	spin_unlock_irqrestore(&dum->lock, flags);
2041 
2042 	return HRTIMER_NORESTART;
2043 }
2044 
2045 /*-------------------------------------------------------------------------*/
2046 
2047 #define PORT_C_MASK \
2048 	((USB_PORT_STAT_C_CONNECTION \
2049 	| USB_PORT_STAT_C_ENABLE \
2050 	| USB_PORT_STAT_C_SUSPEND \
2051 	| USB_PORT_STAT_C_OVERCURRENT \
2052 	| USB_PORT_STAT_C_RESET) << 16)
2053 
2054 static int dummy_hub_status(struct usb_hcd *hcd, char *buf)
2055 {
2056 	struct dummy_hcd	*dum_hcd;
2057 	unsigned long		flags;
2058 	int			retval = 0;
2059 
2060 	dum_hcd = hcd_to_dummy_hcd(hcd);
2061 
2062 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2063 	if (!HCD_HW_ACCESSIBLE(hcd))
2064 		goto done;
2065 
2066 	if (dum_hcd->resuming && time_after_eq(jiffies, dum_hcd->re_timeout)) {
2067 		dum_hcd->port_status |= (USB_PORT_STAT_C_SUSPEND << 16);
2068 		dum_hcd->port_status &= ~USB_PORT_STAT_SUSPEND;
2069 		set_link_state(dum_hcd);
2070 	}
2071 
2072 	if ((dum_hcd->port_status & PORT_C_MASK) != 0) {
2073 		*buf = (1 << 1);
2074 		dev_dbg(dummy_dev(dum_hcd), "port status 0x%08x has changes\n",
2075 				dum_hcd->port_status);
2076 		retval = 1;
2077 		if (dum_hcd->rh_state == DUMMY_RH_SUSPENDED)
2078 			usb_hcd_resume_root_hub(hcd);
2079 	}
2080 done:
2081 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2082 	return retval;
2083 }
2084 
2085 /* usb 3.0 root hub device descriptor */
2086 static struct {
2087 	struct usb_bos_descriptor bos;
2088 	struct usb_ss_cap_descriptor ss_cap;
2089 } __packed usb3_bos_desc = {
2090 
2091 	.bos = {
2092 		.bLength		= USB_DT_BOS_SIZE,
2093 		.bDescriptorType	= USB_DT_BOS,
2094 		.wTotalLength		= cpu_to_le16(sizeof(usb3_bos_desc)),
2095 		.bNumDeviceCaps		= 1,
2096 	},
2097 	.ss_cap = {
2098 		.bLength		= USB_DT_USB_SS_CAP_SIZE,
2099 		.bDescriptorType	= USB_DT_DEVICE_CAPABILITY,
2100 		.bDevCapabilityType	= USB_SS_CAP_TYPE,
2101 		.wSpeedSupported	= cpu_to_le16(USB_5GBPS_OPERATION),
2102 		.bFunctionalitySupport	= ilog2(USB_5GBPS_OPERATION),
2103 	},
2104 };
2105 
2106 static inline void
2107 ss_hub_descriptor(struct usb_hub_descriptor *desc)
2108 {
2109 	memset(desc, 0, sizeof *desc);
2110 	desc->bDescriptorType = USB_DT_SS_HUB;
2111 	desc->bDescLength = 12;
2112 	desc->wHubCharacteristics = cpu_to_le16(
2113 			HUB_CHAR_INDV_PORT_LPSM |
2114 			HUB_CHAR_COMMON_OCPM);
2115 	desc->bNbrPorts = 1;
2116 	desc->u.ss.bHubHdrDecLat = 0x04; /* Worst case: 0.4 micro sec*/
2117 	desc->u.ss.DeviceRemovable = 0;
2118 }
2119 
2120 static inline void hub_descriptor(struct usb_hub_descriptor *desc)
2121 {
2122 	memset(desc, 0, sizeof *desc);
2123 	desc->bDescriptorType = USB_DT_HUB;
2124 	desc->bDescLength = 9;
2125 	desc->wHubCharacteristics = cpu_to_le16(
2126 			HUB_CHAR_INDV_PORT_LPSM |
2127 			HUB_CHAR_COMMON_OCPM);
2128 	desc->bNbrPorts = 1;
2129 	desc->u.hs.DeviceRemovable[0] = 0;
2130 	desc->u.hs.DeviceRemovable[1] = 0xff;	/* PortPwrCtrlMask */
2131 }
2132 
2133 static int dummy_hub_control(
2134 	struct usb_hcd	*hcd,
2135 	u16		typeReq,
2136 	u16		wValue,
2137 	u16		wIndex,
2138 	char		*buf,
2139 	u16		wLength
2140 ) {
2141 	struct dummy_hcd *dum_hcd;
2142 	int		retval = 0;
2143 	unsigned long	flags;
2144 
2145 	if (!HCD_HW_ACCESSIBLE(hcd))
2146 		return -ETIMEDOUT;
2147 
2148 	dum_hcd = hcd_to_dummy_hcd(hcd);
2149 
2150 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2151 	switch (typeReq) {
2152 	case ClearHubFeature:
2153 		break;
2154 	case ClearPortFeature:
2155 		if (wIndex != 1)
2156 			goto error;
2157 		switch (wValue) {
2158 		case USB_PORT_FEAT_SUSPEND:
2159 			if (hcd->speed == HCD_USB3) {
2160 				dev_dbg(dummy_dev(dum_hcd),
2161 					 "USB_PORT_FEAT_SUSPEND req not "
2162 					 "supported for USB 3.0 roothub\n");
2163 				goto error;
2164 			}
2165 			if (dum_hcd->port_status & USB_PORT_STAT_SUSPEND) {
2166 				/* 20msec resume signaling */
2167 				dum_hcd->resuming = 1;
2168 				dum_hcd->re_timeout = jiffies +
2169 						msecs_to_jiffies(20);
2170 			}
2171 			break;
2172 		case USB_PORT_FEAT_POWER:
2173 			dev_dbg(dummy_dev(dum_hcd), "power-off\n");
2174 			if (hcd->speed == HCD_USB3)
2175 				dum_hcd->port_status &= ~USB_SS_PORT_STAT_POWER;
2176 			else
2177 				dum_hcd->port_status &= ~USB_PORT_STAT_POWER;
2178 			set_link_state(dum_hcd);
2179 			break;
2180 		case USB_PORT_FEAT_ENABLE:
2181 		case USB_PORT_FEAT_C_ENABLE:
2182 		case USB_PORT_FEAT_C_SUSPEND:
2183 			/* Not allowed for USB-3 */
2184 			if (hcd->speed == HCD_USB3)
2185 				goto error;
2186 			fallthrough;
2187 		case USB_PORT_FEAT_C_CONNECTION:
2188 		case USB_PORT_FEAT_C_RESET:
2189 			dum_hcd->port_status &= ~(1 << wValue);
2190 			set_link_state(dum_hcd);
2191 			break;
2192 		default:
2193 		/* Disallow INDICATOR and C_OVER_CURRENT */
2194 			goto error;
2195 		}
2196 		break;
2197 	case GetHubDescriptor:
2198 		if (hcd->speed == HCD_USB3 &&
2199 				(wLength < USB_DT_SS_HUB_SIZE ||
2200 				 wValue != (USB_DT_SS_HUB << 8))) {
2201 			dev_dbg(dummy_dev(dum_hcd),
2202 				"Wrong hub descriptor type for "
2203 				"USB 3.0 roothub.\n");
2204 			goto error;
2205 		}
2206 		if (hcd->speed == HCD_USB3)
2207 			ss_hub_descriptor((struct usb_hub_descriptor *) buf);
2208 		else
2209 			hub_descriptor((struct usb_hub_descriptor *) buf);
2210 		break;
2211 
2212 	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
2213 		if (hcd->speed != HCD_USB3)
2214 			goto error;
2215 
2216 		if ((wValue >> 8) != USB_DT_BOS)
2217 			goto error;
2218 
2219 		memcpy(buf, &usb3_bos_desc, sizeof(usb3_bos_desc));
2220 		retval = sizeof(usb3_bos_desc);
2221 		break;
2222 
2223 	case GetHubStatus:
2224 		*(__le32 *) buf = cpu_to_le32(0);
2225 		break;
2226 	case GetPortStatus:
2227 		if (wIndex != 1)
2228 			retval = -EPIPE;
2229 
2230 		/* whoever resets or resumes must GetPortStatus to
2231 		 * complete it!!
2232 		 */
2233 		if (dum_hcd->resuming &&
2234 				time_after_eq(jiffies, dum_hcd->re_timeout)) {
2235 			dum_hcd->port_status |= (USB_PORT_STAT_C_SUSPEND << 16);
2236 			dum_hcd->port_status &= ~USB_PORT_STAT_SUSPEND;
2237 		}
2238 		if ((dum_hcd->port_status & USB_PORT_STAT_RESET) != 0 &&
2239 				time_after_eq(jiffies, dum_hcd->re_timeout)) {
2240 			dum_hcd->port_status |= (USB_PORT_STAT_C_RESET << 16);
2241 			dum_hcd->port_status &= ~USB_PORT_STAT_RESET;
2242 			if (dum_hcd->dum->pullup) {
2243 				dum_hcd->port_status |= USB_PORT_STAT_ENABLE;
2244 
2245 				if (hcd->speed < HCD_USB3) {
2246 					switch (dum_hcd->dum->gadget.speed) {
2247 					case USB_SPEED_HIGH:
2248 						dum_hcd->port_status |=
2249 						      USB_PORT_STAT_HIGH_SPEED;
2250 						break;
2251 					case USB_SPEED_LOW:
2252 						dum_hcd->dum->gadget.ep0->
2253 							maxpacket = 8;
2254 						dum_hcd->port_status |=
2255 							USB_PORT_STAT_LOW_SPEED;
2256 						break;
2257 					default:
2258 						break;
2259 					}
2260 				}
2261 			}
2262 		}
2263 		set_link_state(dum_hcd);
2264 		((__le16 *) buf)[0] = cpu_to_le16(dum_hcd->port_status);
2265 		((__le16 *) buf)[1] = cpu_to_le16(dum_hcd->port_status >> 16);
2266 		break;
2267 	case SetHubFeature:
2268 		retval = -EPIPE;
2269 		break;
2270 	case SetPortFeature:
2271 		if (wIndex != 1)
2272 			goto error;
2273 		switch (wValue) {
2274 		case USB_PORT_FEAT_LINK_STATE:
2275 			if (hcd->speed != HCD_USB3) {
2276 				dev_dbg(dummy_dev(dum_hcd),
2277 					 "USB_PORT_FEAT_LINK_STATE req not "
2278 					 "supported for USB 2.0 roothub\n");
2279 				goto error;
2280 			}
2281 			/*
2282 			 * Since this is dummy we don't have an actual link so
2283 			 * there is nothing to do for the SET_LINK_STATE cmd
2284 			 */
2285 			break;
2286 		case USB_PORT_FEAT_U1_TIMEOUT:
2287 		case USB_PORT_FEAT_U2_TIMEOUT:
2288 			/* TODO: add suspend/resume support! */
2289 			if (hcd->speed != HCD_USB3) {
2290 				dev_dbg(dummy_dev(dum_hcd),
2291 					 "USB_PORT_FEAT_U1/2_TIMEOUT req not "
2292 					 "supported for USB 2.0 roothub\n");
2293 				goto error;
2294 			}
2295 			break;
2296 		case USB_PORT_FEAT_SUSPEND:
2297 			/* Applicable only for USB2.0 hub */
2298 			if (hcd->speed == HCD_USB3) {
2299 				dev_dbg(dummy_dev(dum_hcd),
2300 					 "USB_PORT_FEAT_SUSPEND req not "
2301 					 "supported for USB 3.0 roothub\n");
2302 				goto error;
2303 			}
2304 			if (dum_hcd->active) {
2305 				dum_hcd->port_status |= USB_PORT_STAT_SUSPEND;
2306 
2307 				/* HNP would happen here; for now we
2308 				 * assume b_bus_req is always true.
2309 				 */
2310 				set_link_state(dum_hcd);
2311 				if (((1 << USB_DEVICE_B_HNP_ENABLE)
2312 						& dum_hcd->dum->devstatus) != 0)
2313 					dev_dbg(dummy_dev(dum_hcd),
2314 							"no HNP yet!\n");
2315 			}
2316 			break;
2317 		case USB_PORT_FEAT_POWER:
2318 			if (hcd->speed == HCD_USB3)
2319 				dum_hcd->port_status |= USB_SS_PORT_STAT_POWER;
2320 			else
2321 				dum_hcd->port_status |= USB_PORT_STAT_POWER;
2322 			set_link_state(dum_hcd);
2323 			break;
2324 		case USB_PORT_FEAT_BH_PORT_RESET:
2325 			/* Applicable only for USB3.0 hub */
2326 			if (hcd->speed != HCD_USB3) {
2327 				dev_dbg(dummy_dev(dum_hcd),
2328 					 "USB_PORT_FEAT_BH_PORT_RESET req not "
2329 					 "supported for USB 2.0 roothub\n");
2330 				goto error;
2331 			}
2332 			fallthrough;
2333 		case USB_PORT_FEAT_RESET:
2334 			if (!(dum_hcd->port_status & USB_PORT_STAT_CONNECTION))
2335 				break;
2336 			/* if it's already enabled, disable */
2337 			if (hcd->speed == HCD_USB3) {
2338 				dum_hcd->port_status =
2339 					(USB_SS_PORT_STAT_POWER |
2340 					 USB_PORT_STAT_CONNECTION |
2341 					 USB_PORT_STAT_RESET);
2342 			} else {
2343 				dum_hcd->port_status &= ~(USB_PORT_STAT_ENABLE
2344 					| USB_PORT_STAT_LOW_SPEED
2345 					| USB_PORT_STAT_HIGH_SPEED);
2346 				dum_hcd->port_status |= USB_PORT_STAT_RESET;
2347 			}
2348 			/*
2349 			 * We want to reset device status. All but the
2350 			 * Self powered feature
2351 			 */
2352 			dum_hcd->dum->devstatus &=
2353 				(1 << USB_DEVICE_SELF_POWERED);
2354 			/*
2355 			 * FIXME USB3.0: what is the correct reset signaling
2356 			 * interval? Is it still 50msec as for HS?
2357 			 */
2358 			dum_hcd->re_timeout = jiffies + msecs_to_jiffies(50);
2359 			set_link_state(dum_hcd);
2360 			break;
2361 		case USB_PORT_FEAT_C_CONNECTION:
2362 		case USB_PORT_FEAT_C_RESET:
2363 		case USB_PORT_FEAT_C_ENABLE:
2364 		case USB_PORT_FEAT_C_SUSPEND:
2365 			/* Not allowed for USB-3, and ignored for USB-2 */
2366 			if (hcd->speed == HCD_USB3)
2367 				goto error;
2368 			break;
2369 		default:
2370 		/* Disallow TEST, INDICATOR, and C_OVER_CURRENT */
2371 			goto error;
2372 		}
2373 		break;
2374 	case GetPortErrorCount:
2375 		if (hcd->speed != HCD_USB3) {
2376 			dev_dbg(dummy_dev(dum_hcd),
2377 				 "GetPortErrorCount req not "
2378 				 "supported for USB 2.0 roothub\n");
2379 			goto error;
2380 		}
2381 		/* We'll always return 0 since this is a dummy hub */
2382 		*(__le32 *) buf = cpu_to_le32(0);
2383 		break;
2384 	case SetHubDepth:
2385 		if (hcd->speed != HCD_USB3) {
2386 			dev_dbg(dummy_dev(dum_hcd),
2387 				 "SetHubDepth req not supported for "
2388 				 "USB 2.0 roothub\n");
2389 			goto error;
2390 		}
2391 		break;
2392 	default:
2393 		dev_dbg(dummy_dev(dum_hcd),
2394 			"hub control req%04x v%04x i%04x l%d\n",
2395 			typeReq, wValue, wIndex, wLength);
2396 error:
2397 		/* "protocol stall" on error */
2398 		retval = -EPIPE;
2399 	}
2400 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2401 
2402 	if ((dum_hcd->port_status & PORT_C_MASK) != 0)
2403 		usb_hcd_poll_rh_status(hcd);
2404 	return retval;
2405 }
2406 
2407 static int dummy_bus_suspend(struct usb_hcd *hcd)
2408 {
2409 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2410 
2411 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
2412 
2413 	spin_lock_irq(&dum_hcd->dum->lock);
2414 	dum_hcd->rh_state = DUMMY_RH_SUSPENDED;
2415 	set_link_state(dum_hcd);
2416 	hcd->state = HC_STATE_SUSPENDED;
2417 	spin_unlock_irq(&dum_hcd->dum->lock);
2418 	return 0;
2419 }
2420 
2421 static int dummy_bus_resume(struct usb_hcd *hcd)
2422 {
2423 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2424 	int rc = 0;
2425 
2426 	dev_dbg(&hcd->self.root_hub->dev, "%s\n", __func__);
2427 
2428 	spin_lock_irq(&dum_hcd->dum->lock);
2429 	if (!HCD_HW_ACCESSIBLE(hcd)) {
2430 		rc = -ESHUTDOWN;
2431 	} else {
2432 		dum_hcd->rh_state = DUMMY_RH_RUNNING;
2433 		set_link_state(dum_hcd);
2434 		if (!list_empty(&dum_hcd->urbp_list)) {
2435 			dum_hcd->timer_pending = 1;
2436 			hrtimer_start(&dum_hcd->timer, ns_to_ktime(0), HRTIMER_MODE_REL_SOFT);
2437 		}
2438 		hcd->state = HC_STATE_RUNNING;
2439 	}
2440 	spin_unlock_irq(&dum_hcd->dum->lock);
2441 	return rc;
2442 }
2443 
2444 /*-------------------------------------------------------------------------*/
2445 
2446 static inline ssize_t show_urb(char *buf, size_t size, struct urb *urb)
2447 {
2448 	int ep = usb_pipeendpoint(urb->pipe);
2449 
2450 	return scnprintf(buf, size,
2451 		"urb/%p %s ep%d%s%s len %d/%d\n",
2452 		urb,
2453 		({ char *s;
2454 		switch (urb->dev->speed) {
2455 		case USB_SPEED_LOW:
2456 			s = "ls";
2457 			break;
2458 		case USB_SPEED_FULL:
2459 			s = "fs";
2460 			break;
2461 		case USB_SPEED_HIGH:
2462 			s = "hs";
2463 			break;
2464 		case USB_SPEED_SUPER:
2465 			s = "ss";
2466 			break;
2467 		default:
2468 			s = "?";
2469 			break;
2470 		 } s; }),
2471 		ep, ep ? (usb_urb_dir_in(urb) ? "in" : "out") : "",
2472 		({ char *s; \
2473 		switch (usb_pipetype(urb->pipe)) { \
2474 		case PIPE_CONTROL: \
2475 			s = ""; \
2476 			break; \
2477 		case PIPE_BULK: \
2478 			s = "-bulk"; \
2479 			break; \
2480 		case PIPE_INTERRUPT: \
2481 			s = "-int"; \
2482 			break; \
2483 		default: \
2484 			s = "-iso"; \
2485 			break; \
2486 		} s; }),
2487 		urb->actual_length, urb->transfer_buffer_length);
2488 }
2489 
2490 static ssize_t urbs_show(struct device *dev, struct device_attribute *attr,
2491 		char *buf)
2492 {
2493 	struct usb_hcd		*hcd = dev_get_drvdata(dev);
2494 	struct dummy_hcd	*dum_hcd = hcd_to_dummy_hcd(hcd);
2495 	struct urbp		*urbp;
2496 	size_t			size = 0;
2497 	unsigned long		flags;
2498 
2499 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2500 	list_for_each_entry(urbp, &dum_hcd->urbp_list, urbp_list) {
2501 		size_t		temp;
2502 
2503 		temp = show_urb(buf, PAGE_SIZE - size, urbp->urb);
2504 		buf += temp;
2505 		size += temp;
2506 	}
2507 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2508 
2509 	return size;
2510 }
2511 static DEVICE_ATTR_RO(urbs);
2512 
2513 static int dummy_start_ss(struct dummy_hcd *dum_hcd)
2514 {
2515 	hrtimer_setup(&dum_hcd->timer, dummy_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
2516 	dum_hcd->rh_state = DUMMY_RH_RUNNING;
2517 	dum_hcd->stream_en_ep = 0;
2518 	INIT_LIST_HEAD(&dum_hcd->urbp_list);
2519 	dummy_hcd_to_hcd(dum_hcd)->power_budget = POWER_BUDGET_3;
2520 	dummy_hcd_to_hcd(dum_hcd)->state = HC_STATE_RUNNING;
2521 	dummy_hcd_to_hcd(dum_hcd)->uses_new_polling = 1;
2522 #ifdef CONFIG_USB_OTG
2523 	dummy_hcd_to_hcd(dum_hcd)->self.otg_port = 1;
2524 #endif
2525 	return 0;
2526 
2527 	/* FIXME 'urbs' should be a per-device thing, maybe in usbcore */
2528 	return device_create_file(dummy_dev(dum_hcd), &dev_attr_urbs);
2529 }
2530 
2531 static int dummy_start(struct usb_hcd *hcd)
2532 {
2533 	struct dummy_hcd	*dum_hcd = hcd_to_dummy_hcd(hcd);
2534 
2535 	/*
2536 	 * HOST side init ... we emulate a root hub that'll only ever
2537 	 * talk to one device (the gadget side).  Also appears in sysfs,
2538 	 * just like more familiar pci-based HCDs.
2539 	 */
2540 	if (!usb_hcd_is_primary_hcd(hcd))
2541 		return dummy_start_ss(dum_hcd);
2542 
2543 	spin_lock_init(&dum_hcd->dum->lock);
2544 	hrtimer_setup(&dum_hcd->timer, dummy_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
2545 	dum_hcd->rh_state = DUMMY_RH_RUNNING;
2546 
2547 	INIT_LIST_HEAD(&dum_hcd->urbp_list);
2548 
2549 	hcd->power_budget = POWER_BUDGET;
2550 	hcd->state = HC_STATE_RUNNING;
2551 	hcd->uses_new_polling = 1;
2552 
2553 #ifdef CONFIG_USB_OTG
2554 	hcd->self.otg_port = 1;
2555 #endif
2556 
2557 	/* FIXME 'urbs' should be a per-device thing, maybe in usbcore */
2558 	return device_create_file(dummy_dev(dum_hcd), &dev_attr_urbs);
2559 }
2560 
2561 static void dummy_stop(struct usb_hcd *hcd)
2562 {
2563 	struct dummy_hcd	*dum_hcd = hcd_to_dummy_hcd(hcd);
2564 
2565 	hrtimer_cancel(&dum_hcd->timer);
2566 	dum_hcd->timer_pending = 0;
2567 	device_remove_file(dummy_dev(dum_hcd), &dev_attr_urbs);
2568 	dev_info(dummy_dev(dum_hcd), "stopped\n");
2569 }
2570 
2571 /*-------------------------------------------------------------------------*/
2572 
2573 static int dummy_h_get_frame(struct usb_hcd *hcd)
2574 {
2575 	return dummy_g_get_frame(NULL);
2576 }
2577 
2578 static int dummy_setup(struct usb_hcd *hcd)
2579 {
2580 	struct dummy *dum;
2581 
2582 	dum = *((void **)dev_get_platdata(hcd->self.controller));
2583 	hcd->self.sg_tablesize = ~0;
2584 	if (usb_hcd_is_primary_hcd(hcd)) {
2585 		dum->hs_hcd = hcd_to_dummy_hcd(hcd);
2586 		dum->hs_hcd->dum = dum;
2587 		/*
2588 		 * Mark the first roothub as being USB 2.0.
2589 		 * The USB 3.0 roothub will be registered later by
2590 		 * dummy_hcd_probe()
2591 		 */
2592 		hcd->speed = HCD_USB2;
2593 		hcd->self.root_hub->speed = USB_SPEED_HIGH;
2594 	} else {
2595 		dum->ss_hcd = hcd_to_dummy_hcd(hcd);
2596 		dum->ss_hcd->dum = dum;
2597 		hcd->speed = HCD_USB3;
2598 		hcd->self.root_hub->speed = USB_SPEED_SUPER;
2599 	}
2600 	return 0;
2601 }
2602 
2603 /* Change a group of bulk endpoints to support multiple stream IDs */
2604 static int dummy_alloc_streams(struct usb_hcd *hcd, struct usb_device *udev,
2605 	struct usb_host_endpoint **eps, unsigned int num_eps,
2606 	unsigned int num_streams, gfp_t mem_flags)
2607 {
2608 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2609 	unsigned long flags;
2610 	int max_stream;
2611 	int ret_streams = num_streams;
2612 	unsigned int index;
2613 	unsigned int i;
2614 
2615 	if (!num_eps)
2616 		return -EINVAL;
2617 
2618 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2619 	for (i = 0; i < num_eps; i++) {
2620 		index = dummy_get_ep_idx(&eps[i]->desc);
2621 		if ((1 << index) & dum_hcd->stream_en_ep) {
2622 			ret_streams = -EINVAL;
2623 			goto out;
2624 		}
2625 		max_stream = usb_ss_max_streams(&eps[i]->ss_ep_comp);
2626 		if (!max_stream) {
2627 			ret_streams = -EINVAL;
2628 			goto out;
2629 		}
2630 		if (max_stream < ret_streams) {
2631 			dev_dbg(dummy_dev(dum_hcd), "Ep 0x%x only supports %u "
2632 					"stream IDs.\n",
2633 					eps[i]->desc.bEndpointAddress,
2634 					max_stream);
2635 			ret_streams = max_stream;
2636 		}
2637 	}
2638 
2639 	for (i = 0; i < num_eps; i++) {
2640 		index = dummy_get_ep_idx(&eps[i]->desc);
2641 		dum_hcd->stream_en_ep |= 1 << index;
2642 		set_max_streams_for_pipe(dum_hcd,
2643 				usb_endpoint_num(&eps[i]->desc), ret_streams);
2644 	}
2645 out:
2646 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2647 	return ret_streams;
2648 }
2649 
2650 /* Reverts a group of bulk endpoints back to not using stream IDs. */
2651 static int dummy_free_streams(struct usb_hcd *hcd, struct usb_device *udev,
2652 	struct usb_host_endpoint **eps, unsigned int num_eps,
2653 	gfp_t mem_flags)
2654 {
2655 	struct dummy_hcd *dum_hcd = hcd_to_dummy_hcd(hcd);
2656 	unsigned long flags;
2657 	int ret;
2658 	unsigned int index;
2659 	unsigned int i;
2660 
2661 	spin_lock_irqsave(&dum_hcd->dum->lock, flags);
2662 	for (i = 0; i < num_eps; i++) {
2663 		index = dummy_get_ep_idx(&eps[i]->desc);
2664 		if (!((1 << index) & dum_hcd->stream_en_ep)) {
2665 			ret = -EINVAL;
2666 			goto out;
2667 		}
2668 	}
2669 
2670 	for (i = 0; i < num_eps; i++) {
2671 		index = dummy_get_ep_idx(&eps[i]->desc);
2672 		dum_hcd->stream_en_ep &= ~(1 << index);
2673 		set_max_streams_for_pipe(dum_hcd,
2674 				usb_endpoint_num(&eps[i]->desc), 0);
2675 	}
2676 	ret = 0;
2677 out:
2678 	spin_unlock_irqrestore(&dum_hcd->dum->lock, flags);
2679 	return ret;
2680 }
2681 
2682 static struct hc_driver dummy_hcd = {
2683 	.description =		(char *) driver_name,
2684 	.product_desc =		"Dummy host controller",
2685 	.hcd_priv_size =	sizeof(struct dummy_hcd),
2686 
2687 	.reset =		dummy_setup,
2688 	.start =		dummy_start,
2689 	.stop =			dummy_stop,
2690 
2691 	.urb_enqueue =		dummy_urb_enqueue,
2692 	.urb_dequeue =		dummy_urb_dequeue,
2693 
2694 	.get_frame_number =	dummy_h_get_frame,
2695 
2696 	.hub_status_data =	dummy_hub_status,
2697 	.hub_control =		dummy_hub_control,
2698 	.bus_suspend =		dummy_bus_suspend,
2699 	.bus_resume =		dummy_bus_resume,
2700 
2701 	.alloc_streams =	dummy_alloc_streams,
2702 	.free_streams =		dummy_free_streams,
2703 };
2704 
2705 static int dummy_hcd_probe(struct platform_device *pdev)
2706 {
2707 	struct dummy		*dum;
2708 	struct usb_hcd		*hs_hcd;
2709 	struct usb_hcd		*ss_hcd;
2710 	int			retval;
2711 
2712 	dev_info(&pdev->dev, "%s, driver " DRIVER_VERSION "\n", driver_desc);
2713 	dum = *((void **)dev_get_platdata(&pdev->dev));
2714 
2715 	if (mod_data.is_super_speed)
2716 		dummy_hcd.flags = HCD_USB3 | HCD_SHARED;
2717 	else if (mod_data.is_high_speed)
2718 		dummy_hcd.flags = HCD_USB2;
2719 	else
2720 		dummy_hcd.flags = HCD_USB11;
2721 	hs_hcd = usb_create_hcd(&dummy_hcd, &pdev->dev, dev_name(&pdev->dev));
2722 	if (!hs_hcd)
2723 		return -ENOMEM;
2724 	hs_hcd->has_tt = 1;
2725 
2726 	retval = usb_add_hcd(hs_hcd, 0, 0);
2727 	if (retval)
2728 		goto put_usb2_hcd;
2729 
2730 	if (mod_data.is_super_speed) {
2731 		ss_hcd = usb_create_shared_hcd(&dummy_hcd, &pdev->dev,
2732 					dev_name(&pdev->dev), hs_hcd);
2733 		if (!ss_hcd) {
2734 			retval = -ENOMEM;
2735 			goto dealloc_usb2_hcd;
2736 		}
2737 
2738 		retval = usb_add_hcd(ss_hcd, 0, 0);
2739 		if (retval)
2740 			goto put_usb3_hcd;
2741 	}
2742 	return 0;
2743 
2744 put_usb3_hcd:
2745 	usb_put_hcd(ss_hcd);
2746 dealloc_usb2_hcd:
2747 	usb_remove_hcd(hs_hcd);
2748 put_usb2_hcd:
2749 	usb_put_hcd(hs_hcd);
2750 	dum->hs_hcd = dum->ss_hcd = NULL;
2751 	return retval;
2752 }
2753 
2754 static void dummy_hcd_remove(struct platform_device *pdev)
2755 {
2756 	struct dummy		*dum;
2757 
2758 	dum = hcd_to_dummy_hcd(platform_get_drvdata(pdev))->dum;
2759 
2760 	if (dum->ss_hcd) {
2761 		usb_remove_hcd(dummy_hcd_to_hcd(dum->ss_hcd));
2762 		usb_put_hcd(dummy_hcd_to_hcd(dum->ss_hcd));
2763 	}
2764 
2765 	usb_remove_hcd(dummy_hcd_to_hcd(dum->hs_hcd));
2766 	usb_put_hcd(dummy_hcd_to_hcd(dum->hs_hcd));
2767 
2768 	dum->hs_hcd = NULL;
2769 	dum->ss_hcd = NULL;
2770 }
2771 
2772 static int dummy_hcd_suspend(struct platform_device *pdev, pm_message_t state)
2773 {
2774 	struct usb_hcd		*hcd;
2775 	struct dummy_hcd	*dum_hcd;
2776 	int			rc = 0;
2777 
2778 	dev_dbg(&pdev->dev, "%s\n", __func__);
2779 
2780 	hcd = platform_get_drvdata(pdev);
2781 	dum_hcd = hcd_to_dummy_hcd(hcd);
2782 	if (dum_hcd->rh_state == DUMMY_RH_RUNNING) {
2783 		dev_warn(&pdev->dev, "Root hub isn't suspended!\n");
2784 		rc = -EBUSY;
2785 	} else
2786 		clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2787 	return rc;
2788 }
2789 
2790 static int dummy_hcd_resume(struct platform_device *pdev)
2791 {
2792 	struct usb_hcd		*hcd;
2793 
2794 	dev_dbg(&pdev->dev, "%s\n", __func__);
2795 
2796 	hcd = platform_get_drvdata(pdev);
2797 	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2798 	usb_hcd_poll_rh_status(hcd);
2799 	return 0;
2800 }
2801 
2802 static struct platform_driver dummy_hcd_driver = {
2803 	.probe		= dummy_hcd_probe,
2804 	.remove		= dummy_hcd_remove,
2805 	.suspend	= dummy_hcd_suspend,
2806 	.resume		= dummy_hcd_resume,
2807 	.driver		= {
2808 		.name	= driver_name,
2809 	},
2810 };
2811 
2812 /*-------------------------------------------------------------------------*/
2813 #define MAX_NUM_UDC	32
2814 static struct platform_device *the_udc_pdev[MAX_NUM_UDC];
2815 static struct platform_device *the_hcd_pdev[MAX_NUM_UDC];
2816 
2817 static int __init dummy_hcd_init(void)
2818 {
2819 	int	retval = -ENOMEM;
2820 	int	i;
2821 	struct	dummy *dum[MAX_NUM_UDC] = {};
2822 
2823 	if (usb_disabled())
2824 		return -ENODEV;
2825 
2826 	if (!mod_data.is_high_speed && mod_data.is_super_speed)
2827 		return -EINVAL;
2828 
2829 	if (mod_data.num < 1 || mod_data.num > MAX_NUM_UDC) {
2830 		pr_err("Number of emulated UDC must be in range of 1...%d\n",
2831 				MAX_NUM_UDC);
2832 		return -EINVAL;
2833 	}
2834 
2835 	for (i = 0; i < mod_data.num; i++) {
2836 		the_hcd_pdev[i] = platform_device_alloc(driver_name, i);
2837 		if (!the_hcd_pdev[i]) {
2838 			i--;
2839 			while (i >= 0)
2840 				platform_device_put(the_hcd_pdev[i--]);
2841 			return retval;
2842 		}
2843 	}
2844 	for (i = 0; i < mod_data.num; i++) {
2845 		the_udc_pdev[i] = platform_device_alloc(gadget_name, i);
2846 		if (!the_udc_pdev[i]) {
2847 			i--;
2848 			while (i >= 0)
2849 				platform_device_put(the_udc_pdev[i--]);
2850 			goto err_alloc_udc;
2851 		}
2852 	}
2853 	for (i = 0; i < mod_data.num; i++) {
2854 		dum[i] = kzalloc_obj(struct dummy);
2855 		if (!dum[i]) {
2856 			retval = -ENOMEM;
2857 			goto err_add_pdata;
2858 		}
2859 		retval = platform_device_add_data(the_hcd_pdev[i], &dum[i],
2860 				sizeof(void *));
2861 		if (retval)
2862 			goto err_add_pdata;
2863 		retval = platform_device_add_data(the_udc_pdev[i], &dum[i],
2864 				sizeof(void *));
2865 		if (retval)
2866 			goto err_add_pdata;
2867 	}
2868 
2869 	retval = platform_driver_register(&dummy_hcd_driver);
2870 	if (retval < 0)
2871 		goto err_add_pdata;
2872 	retval = platform_driver_register(&dummy_udc_driver);
2873 	if (retval < 0)
2874 		goto err_register_udc_driver;
2875 
2876 	for (i = 0; i < mod_data.num; i++) {
2877 		retval = platform_device_add(the_hcd_pdev[i]);
2878 		if (retval < 0) {
2879 			i--;
2880 			while (i >= 0)
2881 				platform_device_del(the_hcd_pdev[i--]);
2882 			goto err_add_hcd;
2883 		}
2884 	}
2885 	for (i = 0; i < mod_data.num; i++) {
2886 		if (!dum[i]->hs_hcd ||
2887 				(!dum[i]->ss_hcd && mod_data.is_super_speed)) {
2888 			/*
2889 			 * The hcd was added successfully but its probe
2890 			 * function failed for some reason.
2891 			 */
2892 			retval = -EINVAL;
2893 			goto err_add_udc;
2894 		}
2895 	}
2896 
2897 	for (i = 0; i < mod_data.num; i++) {
2898 		retval = platform_device_add(the_udc_pdev[i]);
2899 		if (retval < 0) {
2900 			i--;
2901 			while (i >= 0)
2902 				platform_device_del(the_udc_pdev[i--]);
2903 			goto err_add_udc;
2904 		}
2905 	}
2906 
2907 	for (i = 0; i < mod_data.num; i++) {
2908 		if (!platform_get_drvdata(the_udc_pdev[i])) {
2909 			/*
2910 			 * The udc was added successfully but its probe
2911 			 * function failed for some reason.
2912 			 */
2913 			retval = -EINVAL;
2914 			goto err_probe_udc;
2915 		}
2916 	}
2917 	return retval;
2918 
2919 err_probe_udc:
2920 	for (i = 0; i < mod_data.num; i++)
2921 		platform_device_del(the_udc_pdev[i]);
2922 err_add_udc:
2923 	for (i = 0; i < mod_data.num; i++)
2924 		platform_device_del(the_hcd_pdev[i]);
2925 err_add_hcd:
2926 	platform_driver_unregister(&dummy_udc_driver);
2927 err_register_udc_driver:
2928 	platform_driver_unregister(&dummy_hcd_driver);
2929 err_add_pdata:
2930 	for (i = 0; i < mod_data.num; i++)
2931 		kfree(dum[i]);
2932 	for (i = 0; i < mod_data.num; i++)
2933 		platform_device_put(the_udc_pdev[i]);
2934 err_alloc_udc:
2935 	for (i = 0; i < mod_data.num; i++)
2936 		platform_device_put(the_hcd_pdev[i]);
2937 	return retval;
2938 }
2939 module_init(dummy_hcd_init);
2940 
2941 static void __exit dummy_hcd_cleanup(void)
2942 {
2943 	int i;
2944 
2945 	for (i = 0; i < mod_data.num; i++) {
2946 		struct dummy *dum;
2947 
2948 		dum = *((void **)dev_get_platdata(&the_udc_pdev[i]->dev));
2949 
2950 		platform_device_unregister(the_udc_pdev[i]);
2951 		platform_device_unregister(the_hcd_pdev[i]);
2952 		kfree(dum);
2953 	}
2954 	platform_driver_unregister(&dummy_udc_driver);
2955 	platform_driver_unregister(&dummy_hcd_driver);
2956 }
2957 module_exit(dummy_hcd_cleanup);
2958