xref: /linux/drivers/usb/dwc3/ep0.c (revision 1553a1c48281243359a9529a10ddb551f3b967ab)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ep0.c - DesignWare USB3 DRD Controller Endpoint 0 Handling
4  *
5  * Copyright (C) 2010-2011 Texas Instruments Incorporated - https://www.ti.com
6  *
7  * Authors: Felipe Balbi <balbi@ti.com>,
8  *	    Sebastian Andrzej Siewior <bigeasy@linutronix.de>
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/spinlock.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/list.h>
19 #include <linux/dma-mapping.h>
20 
21 #include <linux/usb/ch9.h>
22 #include <linux/usb/gadget.h>
23 #include <linux/usb/composite.h>
24 
25 #include "core.h"
26 #include "debug.h"
27 #include "gadget.h"
28 #include "io.h"
29 
30 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep);
31 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
32 		struct dwc3_ep *dep, struct dwc3_request *req);
33 static int dwc3_ep0_delegate_req(struct dwc3 *dwc,
34 				 struct usb_ctrlrequest *ctrl);
35 
36 static void dwc3_ep0_prepare_one_trb(struct dwc3_ep *dep,
37 		dma_addr_t buf_dma, u32 len, u32 type, bool chain)
38 {
39 	struct dwc3_trb			*trb;
40 	struct dwc3			*dwc;
41 
42 	dwc = dep->dwc;
43 	trb = &dwc->ep0_trb[dep->trb_enqueue];
44 
45 	if (chain)
46 		dep->trb_enqueue++;
47 
48 	trb->bpl = lower_32_bits(buf_dma);
49 	trb->bph = upper_32_bits(buf_dma);
50 	trb->size = len;
51 	trb->ctrl = type;
52 
53 	trb->ctrl |= (DWC3_TRB_CTRL_HWO
54 			| DWC3_TRB_CTRL_ISP_IMI);
55 
56 	if (chain)
57 		trb->ctrl |= DWC3_TRB_CTRL_CHN;
58 	else
59 		trb->ctrl |= (DWC3_TRB_CTRL_IOC
60 				| DWC3_TRB_CTRL_LST);
61 
62 	trace_dwc3_prepare_trb(dep, trb);
63 }
64 
65 static int dwc3_ep0_start_trans(struct dwc3_ep *dep)
66 {
67 	struct dwc3_gadget_ep_cmd_params params;
68 	struct dwc3			*dwc;
69 	int				ret;
70 
71 	if (dep->flags & DWC3_EP_TRANSFER_STARTED)
72 		return 0;
73 
74 	dwc = dep->dwc;
75 
76 	memset(&params, 0, sizeof(params));
77 	params.param0 = upper_32_bits(dwc->ep0_trb_addr);
78 	params.param1 = lower_32_bits(dwc->ep0_trb_addr);
79 
80 	ret = dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_STARTTRANSFER, &params);
81 	if (ret < 0)
82 		return ret;
83 
84 	dwc->ep0_next_event = DWC3_EP0_COMPLETE;
85 
86 	return 0;
87 }
88 
89 static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep,
90 		struct dwc3_request *req)
91 {
92 	struct dwc3		*dwc = dep->dwc;
93 
94 	req->request.actual	= 0;
95 	req->request.status	= -EINPROGRESS;
96 	req->epnum		= dep->number;
97 
98 	list_add_tail(&req->list, &dep->pending_list);
99 
100 	/*
101 	 * Gadget driver might not be quick enough to queue a request
102 	 * before we get a Transfer Not Ready event on this endpoint.
103 	 *
104 	 * In that case, we will set DWC3_EP_PENDING_REQUEST. When that
105 	 * flag is set, it's telling us that as soon as Gadget queues the
106 	 * required request, we should kick the transfer here because the
107 	 * IRQ we were waiting for is long gone.
108 	 */
109 	if (dep->flags & DWC3_EP_PENDING_REQUEST) {
110 		unsigned int direction;
111 
112 		direction = !!(dep->flags & DWC3_EP0_DIR_IN);
113 
114 		if (dwc->ep0state != EP0_DATA_PHASE) {
115 			dev_WARN(dwc->dev, "Unexpected pending request\n");
116 			return 0;
117 		}
118 
119 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
120 
121 		dep->flags &= ~(DWC3_EP_PENDING_REQUEST |
122 				DWC3_EP0_DIR_IN);
123 
124 		return 0;
125 	}
126 
127 	/*
128 	 * In case gadget driver asked us to delay the STATUS phase,
129 	 * handle it here.
130 	 */
131 	if (dwc->delayed_status) {
132 		unsigned int direction;
133 
134 		direction = !dwc->ep0_expect_in;
135 		dwc->delayed_status = false;
136 		usb_gadget_set_state(dwc->gadget, USB_STATE_CONFIGURED);
137 
138 		if (dwc->ep0state == EP0_STATUS_PHASE)
139 			__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
140 
141 		return 0;
142 	}
143 
144 	/*
145 	 * Unfortunately we have uncovered a limitation wrt the Data Phase.
146 	 *
147 	 * Section 9.4 says we can wait for the XferNotReady(DATA) event to
148 	 * come before issueing Start Transfer command, but if we do, we will
149 	 * miss situations where the host starts another SETUP phase instead of
150 	 * the DATA phase.  Such cases happen at least on TD.7.6 of the Link
151 	 * Layer Compliance Suite.
152 	 *
153 	 * The problem surfaces due to the fact that in case of back-to-back
154 	 * SETUP packets there will be no XferNotReady(DATA) generated and we
155 	 * will be stuck waiting for XferNotReady(DATA) forever.
156 	 *
157 	 * By looking at tables 9-13 and 9-14 of the Databook, we can see that
158 	 * it tells us to start Data Phase right away. It also mentions that if
159 	 * we receive a SETUP phase instead of the DATA phase, core will issue
160 	 * XferComplete for the DATA phase, before actually initiating it in
161 	 * the wire, with the TRB's status set to "SETUP_PENDING". Such status
162 	 * can only be used to print some debugging logs, as the core expects
163 	 * us to go through to the STATUS phase and start a CONTROL_STATUS TRB,
164 	 * just so it completes right away, without transferring anything and,
165 	 * only then, we can go back to the SETUP phase.
166 	 *
167 	 * Because of this scenario, SNPS decided to change the programming
168 	 * model of control transfers and support on-demand transfers only for
169 	 * the STATUS phase. To fix the issue we have now, we will always wait
170 	 * for gadget driver to queue the DATA phase's struct usb_request, then
171 	 * start it right away.
172 	 *
173 	 * If we're actually in a 2-stage transfer, we will wait for
174 	 * XferNotReady(STATUS).
175 	 */
176 	if (dwc->three_stage_setup) {
177 		unsigned int direction;
178 
179 		direction = dwc->ep0_expect_in;
180 		dwc->ep0state = EP0_DATA_PHASE;
181 
182 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
183 
184 		dep->flags &= ~DWC3_EP0_DIR_IN;
185 	}
186 
187 	return 0;
188 }
189 
190 int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
191 		gfp_t gfp_flags)
192 {
193 	struct dwc3_request		*req = to_dwc3_request(request);
194 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
195 	struct dwc3			*dwc = dep->dwc;
196 
197 	unsigned long			flags;
198 
199 	int				ret;
200 
201 	spin_lock_irqsave(&dwc->lock, flags);
202 	if (!dep->endpoint.desc || !dwc->pullups_connected || !dwc->connected) {
203 		dev_err(dwc->dev, "%s: can't queue to disabled endpoint\n",
204 				dep->name);
205 		ret = -ESHUTDOWN;
206 		goto out;
207 	}
208 
209 	/* we share one TRB for ep0/1 */
210 	if (!list_empty(&dep->pending_list)) {
211 		ret = -EBUSY;
212 		goto out;
213 	}
214 
215 	ret = __dwc3_gadget_ep0_queue(dep, req);
216 
217 out:
218 	spin_unlock_irqrestore(&dwc->lock, flags);
219 
220 	return ret;
221 }
222 
223 void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
224 {
225 	struct dwc3_ep		*dep;
226 
227 	/* reinitialize physical ep1 */
228 	dep = dwc->eps[1];
229 	dep->flags = DWC3_EP_ENABLED;
230 
231 	/* stall is always issued on EP0 */
232 	dep = dwc->eps[0];
233 	__dwc3_gadget_ep_set_halt(dep, 1, false);
234 	dep->flags = DWC3_EP_ENABLED;
235 	dwc->delayed_status = false;
236 
237 	if (!list_empty(&dep->pending_list)) {
238 		struct dwc3_request	*req;
239 
240 		req = next_request(&dep->pending_list);
241 		if (!dwc->connected)
242 			dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
243 		else
244 			dwc3_gadget_giveback(dep, req, -ECONNRESET);
245 	}
246 
247 	dwc->eps[0]->trb_enqueue = 0;
248 	dwc->eps[1]->trb_enqueue = 0;
249 	dwc->ep0state = EP0_SETUP_PHASE;
250 	dwc3_ep0_out_start(dwc);
251 }
252 
253 int __dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
254 {
255 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
256 	struct dwc3			*dwc = dep->dwc;
257 
258 	dwc3_ep0_stall_and_restart(dwc);
259 
260 	return 0;
261 }
262 
263 int dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
264 {
265 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
266 	struct dwc3			*dwc = dep->dwc;
267 	unsigned long			flags;
268 	int				ret;
269 
270 	spin_lock_irqsave(&dwc->lock, flags);
271 	ret = __dwc3_gadget_ep0_set_halt(ep, value);
272 	spin_unlock_irqrestore(&dwc->lock, flags);
273 
274 	return ret;
275 }
276 
277 void dwc3_ep0_out_start(struct dwc3 *dwc)
278 {
279 	struct dwc3_ep			*dep;
280 	int				ret;
281 	int                             i;
282 
283 	complete(&dwc->ep0_in_setup);
284 
285 	dep = dwc->eps[0];
286 	dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 8,
287 			DWC3_TRBCTL_CONTROL_SETUP, false);
288 	ret = dwc3_ep0_start_trans(dep);
289 	WARN_ON(ret < 0);
290 	for (i = 2; i < DWC3_ENDPOINTS_NUM; i++) {
291 		struct dwc3_ep *dwc3_ep;
292 
293 		dwc3_ep = dwc->eps[i];
294 		if (!dwc3_ep)
295 			continue;
296 
297 		if (!(dwc3_ep->flags & DWC3_EP_DELAY_STOP))
298 			continue;
299 
300 		dwc3_ep->flags &= ~DWC3_EP_DELAY_STOP;
301 		if (dwc->connected)
302 			dwc3_stop_active_transfer(dwc3_ep, true, true);
303 		else
304 			dwc3_remove_requests(dwc, dwc3_ep, -ESHUTDOWN);
305 	}
306 }
307 
308 static struct dwc3_ep *dwc3_wIndex_to_dep(struct dwc3 *dwc, __le16 wIndex_le)
309 {
310 	struct dwc3_ep		*dep;
311 	u32			windex = le16_to_cpu(wIndex_le);
312 	u32			epnum;
313 
314 	epnum = (windex & USB_ENDPOINT_NUMBER_MASK) << 1;
315 	if ((windex & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN)
316 		epnum |= 1;
317 
318 	dep = dwc->eps[epnum];
319 	if (dep == NULL)
320 		return NULL;
321 
322 	if (dep->flags & DWC3_EP_ENABLED)
323 		return dep;
324 
325 	return NULL;
326 }
327 
328 static void dwc3_ep0_status_cmpl(struct usb_ep *ep, struct usb_request *req)
329 {
330 }
331 /*
332  * ch 9.4.5
333  */
334 static int dwc3_ep0_handle_status(struct dwc3 *dwc,
335 		struct usb_ctrlrequest *ctrl)
336 {
337 	struct dwc3_ep		*dep;
338 	u32			recip;
339 	u32			value;
340 	u32			reg;
341 	u16			usb_status = 0;
342 	__le16			*response_pkt;
343 
344 	/* We don't support PTM_STATUS */
345 	value = le16_to_cpu(ctrl->wValue);
346 	if (value != 0)
347 		return -EINVAL;
348 
349 	recip = ctrl->bRequestType & USB_RECIP_MASK;
350 	switch (recip) {
351 	case USB_RECIP_DEVICE:
352 		/*
353 		 * LTM will be set once we know how to set this in HW.
354 		 */
355 		usb_status |= dwc->gadget->is_selfpowered;
356 
357 		if ((dwc->speed == DWC3_DSTS_SUPERSPEED) ||
358 		    (dwc->speed == DWC3_DSTS_SUPERSPEED_PLUS)) {
359 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
360 			if (reg & DWC3_DCTL_INITU1ENA)
361 				usb_status |= 1 << USB_DEV_STAT_U1_ENABLED;
362 			if (reg & DWC3_DCTL_INITU2ENA)
363 				usb_status |= 1 << USB_DEV_STAT_U2_ENABLED;
364 		} else {
365 			usb_status |= dwc->gadget->wakeup_armed <<
366 					USB_DEVICE_REMOTE_WAKEUP;
367 		}
368 
369 		break;
370 
371 	case USB_RECIP_INTERFACE:
372 		/*
373 		 * Function Remote Wake Capable	D0
374 		 * Function Remote Wakeup	D1
375 		 */
376 		return dwc3_ep0_delegate_req(dwc, ctrl);
377 
378 	case USB_RECIP_ENDPOINT:
379 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
380 		if (!dep)
381 			return -EINVAL;
382 
383 		if (dep->flags & DWC3_EP_STALL)
384 			usb_status = 1 << USB_ENDPOINT_HALT;
385 		break;
386 	default:
387 		return -EINVAL;
388 	}
389 
390 	response_pkt = (__le16 *) dwc->setup_buf;
391 	*response_pkt = cpu_to_le16(usb_status);
392 
393 	dep = dwc->eps[0];
394 	dwc->ep0_usb_req.dep = dep;
395 	dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
396 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
397 	dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
398 
399 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
400 }
401 
402 static int dwc3_ep0_handle_u1(struct dwc3 *dwc, enum usb_device_state state,
403 		int set)
404 {
405 	u32 reg;
406 
407 	if (state != USB_STATE_CONFIGURED)
408 		return -EINVAL;
409 	if ((dwc->speed != DWC3_DSTS_SUPERSPEED) &&
410 			(dwc->speed != DWC3_DSTS_SUPERSPEED_PLUS))
411 		return -EINVAL;
412 	if (set && dwc->dis_u1_entry_quirk)
413 		return -EINVAL;
414 
415 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
416 	if (set)
417 		reg |= DWC3_DCTL_INITU1ENA;
418 	else
419 		reg &= ~DWC3_DCTL_INITU1ENA;
420 	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
421 
422 	return 0;
423 }
424 
425 static int dwc3_ep0_handle_u2(struct dwc3 *dwc, enum usb_device_state state,
426 		int set)
427 {
428 	u32 reg;
429 
430 
431 	if (state != USB_STATE_CONFIGURED)
432 		return -EINVAL;
433 	if ((dwc->speed != DWC3_DSTS_SUPERSPEED) &&
434 			(dwc->speed != DWC3_DSTS_SUPERSPEED_PLUS))
435 		return -EINVAL;
436 	if (set && dwc->dis_u2_entry_quirk)
437 		return -EINVAL;
438 
439 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
440 	if (set)
441 		reg |= DWC3_DCTL_INITU2ENA;
442 	else
443 		reg &= ~DWC3_DCTL_INITU2ENA;
444 	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
445 
446 	return 0;
447 }
448 
449 static int dwc3_ep0_handle_test(struct dwc3 *dwc, enum usb_device_state state,
450 		u32 wIndex, int set)
451 {
452 	if ((wIndex & 0xff) != 0)
453 		return -EINVAL;
454 	if (!set)
455 		return -EINVAL;
456 
457 	switch (wIndex >> 8) {
458 	case USB_TEST_J:
459 	case USB_TEST_K:
460 	case USB_TEST_SE0_NAK:
461 	case USB_TEST_PACKET:
462 	case USB_TEST_FORCE_ENABLE:
463 		dwc->test_mode_nr = wIndex >> 8;
464 		dwc->test_mode = true;
465 		break;
466 	default:
467 		return -EINVAL;
468 	}
469 
470 	return 0;
471 }
472 
473 static int dwc3_ep0_handle_device(struct dwc3 *dwc,
474 		struct usb_ctrlrequest *ctrl, int set)
475 {
476 	enum usb_device_state	state;
477 	u32			wValue;
478 	u32			wIndex;
479 	int			ret = 0;
480 
481 	wValue = le16_to_cpu(ctrl->wValue);
482 	wIndex = le16_to_cpu(ctrl->wIndex);
483 	state = dwc->gadget->state;
484 
485 	switch (wValue) {
486 	case USB_DEVICE_REMOTE_WAKEUP:
487 		if (dwc->wakeup_configured)
488 			dwc->gadget->wakeup_armed = set;
489 		else
490 			ret = -EINVAL;
491 		break;
492 	/*
493 	 * 9.4.1 says only for SS, in AddressState only for
494 	 * default control pipe
495 	 */
496 	case USB_DEVICE_U1_ENABLE:
497 		ret = dwc3_ep0_handle_u1(dwc, state, set);
498 		break;
499 	case USB_DEVICE_U2_ENABLE:
500 		ret = dwc3_ep0_handle_u2(dwc, state, set);
501 		break;
502 	case USB_DEVICE_LTM_ENABLE:
503 		ret = -EINVAL;
504 		break;
505 	case USB_DEVICE_TEST_MODE:
506 		ret = dwc3_ep0_handle_test(dwc, state, wIndex, set);
507 		break;
508 	default:
509 		ret = -EINVAL;
510 	}
511 
512 	return ret;
513 }
514 
515 static int dwc3_ep0_handle_intf(struct dwc3 *dwc,
516 		struct usb_ctrlrequest *ctrl, int set)
517 {
518 	u32			wValue;
519 	int			ret = 0;
520 
521 	wValue = le16_to_cpu(ctrl->wValue);
522 
523 	switch (wValue) {
524 	case USB_INTRF_FUNC_SUSPEND:
525 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
526 		break;
527 	default:
528 		ret = -EINVAL;
529 	}
530 
531 	return ret;
532 }
533 
534 static int dwc3_ep0_handle_endpoint(struct dwc3 *dwc,
535 		struct usb_ctrlrequest *ctrl, int set)
536 {
537 	struct dwc3_ep		*dep;
538 	u32			wValue;
539 	int			ret;
540 
541 	wValue = le16_to_cpu(ctrl->wValue);
542 
543 	switch (wValue) {
544 	case USB_ENDPOINT_HALT:
545 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
546 		if (!dep)
547 			return -EINVAL;
548 
549 		if (set == 0 && (dep->flags & DWC3_EP_WEDGE))
550 			break;
551 
552 		ret = __dwc3_gadget_ep_set_halt(dep, set, true);
553 		if (ret)
554 			return -EINVAL;
555 
556 		/* ClearFeature(Halt) may need delayed status */
557 		if (!set && (dep->flags & DWC3_EP_END_TRANSFER_PENDING))
558 			return USB_GADGET_DELAYED_STATUS;
559 
560 		break;
561 	default:
562 		return -EINVAL;
563 	}
564 
565 	return 0;
566 }
567 
568 static int dwc3_ep0_handle_feature(struct dwc3 *dwc,
569 		struct usb_ctrlrequest *ctrl, int set)
570 {
571 	u32			recip;
572 	int			ret;
573 
574 	recip = ctrl->bRequestType & USB_RECIP_MASK;
575 
576 	switch (recip) {
577 	case USB_RECIP_DEVICE:
578 		ret = dwc3_ep0_handle_device(dwc, ctrl, set);
579 		break;
580 	case USB_RECIP_INTERFACE:
581 		ret = dwc3_ep0_handle_intf(dwc, ctrl, set);
582 		break;
583 	case USB_RECIP_ENDPOINT:
584 		ret = dwc3_ep0_handle_endpoint(dwc, ctrl, set);
585 		break;
586 	default:
587 		ret = -EINVAL;
588 	}
589 
590 	return ret;
591 }
592 
593 static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
594 {
595 	enum usb_device_state state = dwc->gadget->state;
596 	u32 addr;
597 	u32 reg;
598 
599 	addr = le16_to_cpu(ctrl->wValue);
600 	if (addr > 127) {
601 		dev_err(dwc->dev, "invalid device address %d\n", addr);
602 		return -EINVAL;
603 	}
604 
605 	if (state == USB_STATE_CONFIGURED) {
606 		dev_err(dwc->dev, "can't SetAddress() from Configured State\n");
607 		return -EINVAL;
608 	}
609 
610 	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
611 	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
612 	reg |= DWC3_DCFG_DEVADDR(addr);
613 	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
614 
615 	if (addr)
616 		usb_gadget_set_state(dwc->gadget, USB_STATE_ADDRESS);
617 	else
618 		usb_gadget_set_state(dwc->gadget, USB_STATE_DEFAULT);
619 
620 	return 0;
621 }
622 
623 static int dwc3_ep0_delegate_req(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
624 {
625 	int ret = -EINVAL;
626 
627 	if (dwc->async_callbacks) {
628 		spin_unlock(&dwc->lock);
629 		ret = dwc->gadget_driver->setup(dwc->gadget, ctrl);
630 		spin_lock(&dwc->lock);
631 	}
632 	return ret;
633 }
634 
635 static int dwc3_ep0_set_config(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
636 {
637 	enum usb_device_state state = dwc->gadget->state;
638 	u32 cfg;
639 	int ret;
640 	u32 reg;
641 
642 	cfg = le16_to_cpu(ctrl->wValue);
643 
644 	switch (state) {
645 	case USB_STATE_DEFAULT:
646 		return -EINVAL;
647 
648 	case USB_STATE_ADDRESS:
649 		dwc3_gadget_start_config(dwc, 2);
650 		dwc3_gadget_clear_tx_fifos(dwc);
651 
652 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
653 		/* if the cfg matches and the cfg is non zero */
654 		if (cfg && (!ret || (ret == USB_GADGET_DELAYED_STATUS))) {
655 
656 			/*
657 			 * only change state if set_config has already
658 			 * been processed. If gadget driver returns
659 			 * USB_GADGET_DELAYED_STATUS, we will wait
660 			 * to change the state on the next usb_ep_queue()
661 			 */
662 			if (ret == 0)
663 				usb_gadget_set_state(dwc->gadget,
664 						USB_STATE_CONFIGURED);
665 
666 			/*
667 			 * Enable transition to U1/U2 state when
668 			 * nothing is pending from application.
669 			 */
670 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
671 			if (!dwc->dis_u1_entry_quirk)
672 				reg |= DWC3_DCTL_ACCEPTU1ENA;
673 			if (!dwc->dis_u2_entry_quirk)
674 				reg |= DWC3_DCTL_ACCEPTU2ENA;
675 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
676 		}
677 		break;
678 
679 	case USB_STATE_CONFIGURED:
680 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
681 		if (!cfg && !ret)
682 			usb_gadget_set_state(dwc->gadget,
683 					USB_STATE_ADDRESS);
684 		break;
685 	default:
686 		ret = -EINVAL;
687 	}
688 	return ret;
689 }
690 
691 static void dwc3_ep0_set_sel_cmpl(struct usb_ep *ep, struct usb_request *req)
692 {
693 	struct dwc3_ep	*dep = to_dwc3_ep(ep);
694 	struct dwc3	*dwc = dep->dwc;
695 
696 	u32		param = 0;
697 	u32		reg;
698 
699 	struct timing {
700 		u8	u1sel;
701 		u8	u1pel;
702 		__le16	u2sel;
703 		__le16	u2pel;
704 	} __packed timing;
705 
706 	int		ret;
707 
708 	memcpy(&timing, req->buf, sizeof(timing));
709 
710 	dwc->u1sel = timing.u1sel;
711 	dwc->u1pel = timing.u1pel;
712 	dwc->u2sel = le16_to_cpu(timing.u2sel);
713 	dwc->u2pel = le16_to_cpu(timing.u2pel);
714 
715 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
716 	if (reg & DWC3_DCTL_INITU2ENA)
717 		param = dwc->u2pel;
718 	if (reg & DWC3_DCTL_INITU1ENA)
719 		param = dwc->u1pel;
720 
721 	/*
722 	 * According to Synopsys Databook, if parameter is
723 	 * greater than 125, a value of zero should be
724 	 * programmed in the register.
725 	 */
726 	if (param > 125)
727 		param = 0;
728 
729 	/* now that we have the time, issue DGCMD Set Sel */
730 	ret = dwc3_send_gadget_generic_command(dwc,
731 			DWC3_DGCMD_SET_PERIODIC_PAR, param);
732 	WARN_ON(ret < 0);
733 }
734 
735 static int dwc3_ep0_set_sel(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
736 {
737 	struct dwc3_ep	*dep;
738 	enum usb_device_state state = dwc->gadget->state;
739 	u16		wLength;
740 
741 	if (state == USB_STATE_DEFAULT)
742 		return -EINVAL;
743 
744 	wLength = le16_to_cpu(ctrl->wLength);
745 
746 	if (wLength != 6) {
747 		dev_err(dwc->dev, "Set SEL should be 6 bytes, got %d\n",
748 				wLength);
749 		return -EINVAL;
750 	}
751 
752 	/*
753 	 * To handle Set SEL we need to receive 6 bytes from Host. So let's
754 	 * queue a usb_request for 6 bytes.
755 	 *
756 	 * Remember, though, this controller can't handle non-wMaxPacketSize
757 	 * aligned transfers on the OUT direction, so we queue a request for
758 	 * wMaxPacketSize instead.
759 	 */
760 	dep = dwc->eps[0];
761 	dwc->ep0_usb_req.dep = dep;
762 	dwc->ep0_usb_req.request.length = dep->endpoint.maxpacket;
763 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
764 	dwc->ep0_usb_req.request.complete = dwc3_ep0_set_sel_cmpl;
765 
766 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
767 }
768 
769 static int dwc3_ep0_set_isoch_delay(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
770 {
771 	u16		wLength;
772 	u16		wValue;
773 	u16		wIndex;
774 
775 	wValue = le16_to_cpu(ctrl->wValue);
776 	wLength = le16_to_cpu(ctrl->wLength);
777 	wIndex = le16_to_cpu(ctrl->wIndex);
778 
779 	if (wIndex || wLength)
780 		return -EINVAL;
781 
782 	dwc->gadget->isoch_delay = wValue;
783 
784 	return 0;
785 }
786 
787 static int dwc3_ep0_std_request(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
788 {
789 	int ret;
790 
791 	switch (ctrl->bRequest) {
792 	case USB_REQ_GET_STATUS:
793 		ret = dwc3_ep0_handle_status(dwc, ctrl);
794 		break;
795 	case USB_REQ_CLEAR_FEATURE:
796 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 0);
797 		break;
798 	case USB_REQ_SET_FEATURE:
799 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 1);
800 		break;
801 	case USB_REQ_SET_ADDRESS:
802 		ret = dwc3_ep0_set_address(dwc, ctrl);
803 		break;
804 	case USB_REQ_SET_CONFIGURATION:
805 		ret = dwc3_ep0_set_config(dwc, ctrl);
806 		break;
807 	case USB_REQ_SET_SEL:
808 		ret = dwc3_ep0_set_sel(dwc, ctrl);
809 		break;
810 	case USB_REQ_SET_ISOCH_DELAY:
811 		ret = dwc3_ep0_set_isoch_delay(dwc, ctrl);
812 		break;
813 	default:
814 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
815 		break;
816 	}
817 
818 	return ret;
819 }
820 
821 static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
822 		const struct dwc3_event_depevt *event)
823 {
824 	struct usb_ctrlrequest *ctrl = (void *) dwc->ep0_trb;
825 	int ret = -EINVAL;
826 	u32 len;
827 
828 	if (!dwc->gadget_driver || !dwc->softconnect || !dwc->connected)
829 		goto out;
830 
831 	trace_dwc3_ctrl_req(ctrl);
832 
833 	len = le16_to_cpu(ctrl->wLength);
834 	if (!len) {
835 		dwc->three_stage_setup = false;
836 		dwc->ep0_expect_in = false;
837 		dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
838 	} else {
839 		dwc->three_stage_setup = true;
840 		dwc->ep0_expect_in = !!(ctrl->bRequestType & USB_DIR_IN);
841 		dwc->ep0_next_event = DWC3_EP0_NRDY_DATA;
842 	}
843 
844 	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
845 		ret = dwc3_ep0_std_request(dwc, ctrl);
846 	else
847 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
848 
849 	if (ret == USB_GADGET_DELAYED_STATUS)
850 		dwc->delayed_status = true;
851 
852 out:
853 	if (ret < 0)
854 		dwc3_ep0_stall_and_restart(dwc);
855 }
856 
857 static void dwc3_ep0_complete_data(struct dwc3 *dwc,
858 		const struct dwc3_event_depevt *event)
859 {
860 	struct dwc3_request	*r;
861 	struct usb_request	*ur;
862 	struct dwc3_trb		*trb;
863 	struct dwc3_ep		*ep0;
864 	u32			transferred = 0;
865 	u32			status;
866 	u32			length;
867 	u8			epnum;
868 
869 	epnum = event->endpoint_number;
870 	ep0 = dwc->eps[0];
871 
872 	dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
873 	trb = dwc->ep0_trb;
874 	trace_dwc3_complete_trb(ep0, trb);
875 
876 	r = next_request(&ep0->pending_list);
877 	if (!r)
878 		return;
879 
880 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
881 	if (status == DWC3_TRBSTS_SETUP_PENDING) {
882 		dwc->setup_packet_pending = true;
883 		if (r)
884 			dwc3_gadget_giveback(ep0, r, -ECONNRESET);
885 
886 		return;
887 	}
888 
889 	ur = &r->request;
890 
891 	length = trb->size & DWC3_TRB_SIZE_MASK;
892 	transferred = ur->length - length;
893 	ur->actual += transferred;
894 
895 	if ((IS_ALIGNED(ur->length, ep0->endpoint.maxpacket) &&
896 	     ur->length && ur->zero) || dwc->ep0_bounced) {
897 		trb++;
898 		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
899 		trace_dwc3_complete_trb(ep0, trb);
900 
901 		if (r->direction)
902 			dwc->eps[1]->trb_enqueue = 0;
903 		else
904 			dwc->eps[0]->trb_enqueue = 0;
905 
906 		dwc->ep0_bounced = false;
907 	}
908 
909 	if ((epnum & 1) && ur->actual < ur->length)
910 		dwc3_ep0_stall_and_restart(dwc);
911 	else
912 		dwc3_gadget_giveback(ep0, r, 0);
913 }
914 
915 static void dwc3_ep0_complete_status(struct dwc3 *dwc,
916 		const struct dwc3_event_depevt *event)
917 {
918 	struct dwc3_request	*r;
919 	struct dwc3_ep		*dep;
920 	struct dwc3_trb		*trb;
921 	u32			status;
922 
923 	dep = dwc->eps[0];
924 	trb = dwc->ep0_trb;
925 
926 	trace_dwc3_complete_trb(dep, trb);
927 
928 	if (!list_empty(&dep->pending_list)) {
929 		r = next_request(&dep->pending_list);
930 
931 		dwc3_gadget_giveback(dep, r, 0);
932 	}
933 
934 	if (dwc->test_mode) {
935 		int ret;
936 
937 		ret = dwc3_gadget_set_test_mode(dwc, dwc->test_mode_nr);
938 		if (ret < 0) {
939 			dev_err(dwc->dev, "invalid test #%d\n",
940 					dwc->test_mode_nr);
941 			dwc3_ep0_stall_and_restart(dwc);
942 			return;
943 		}
944 	}
945 
946 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
947 	if (status == DWC3_TRBSTS_SETUP_PENDING)
948 		dwc->setup_packet_pending = true;
949 
950 	dwc->ep0state = EP0_SETUP_PHASE;
951 	dwc3_ep0_out_start(dwc);
952 }
953 
954 static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
955 			const struct dwc3_event_depevt *event)
956 {
957 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
958 
959 	dep->flags &= ~DWC3_EP_TRANSFER_STARTED;
960 	dep->resource_index = 0;
961 	dwc->setup_packet_pending = false;
962 
963 	switch (dwc->ep0state) {
964 	case EP0_SETUP_PHASE:
965 		dwc3_ep0_inspect_setup(dwc, event);
966 		break;
967 
968 	case EP0_DATA_PHASE:
969 		dwc3_ep0_complete_data(dwc, event);
970 		break;
971 
972 	case EP0_STATUS_PHASE:
973 		dwc3_ep0_complete_status(dwc, event);
974 		break;
975 	default:
976 		WARN(true, "UNKNOWN ep0state %d\n", dwc->ep0state);
977 	}
978 }
979 
980 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
981 		struct dwc3_ep *dep, struct dwc3_request *req)
982 {
983 	unsigned int		trb_length = 0;
984 	int			ret;
985 
986 	req->direction = !!dep->number;
987 
988 	if (req->request.length == 0) {
989 		if (!req->direction)
990 			trb_length = dep->endpoint.maxpacket;
991 
992 		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr, trb_length,
993 				DWC3_TRBCTL_CONTROL_DATA, false);
994 		ret = dwc3_ep0_start_trans(dep);
995 	} else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
996 			&& (dep->number == 0)) {
997 		u32	maxpacket;
998 		u32	rem;
999 
1000 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
1001 				&req->request, dep->number);
1002 		if (ret)
1003 			return;
1004 
1005 		maxpacket = dep->endpoint.maxpacket;
1006 		rem = req->request.length % maxpacket;
1007 		dwc->ep0_bounced = true;
1008 
1009 		/* prepare normal TRB */
1010 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
1011 					 req->request.length,
1012 					 DWC3_TRBCTL_CONTROL_DATA,
1013 					 true);
1014 
1015 		req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1];
1016 
1017 		/* Now prepare one extra TRB to align transfer size */
1018 		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr,
1019 					 maxpacket - rem,
1020 					 DWC3_TRBCTL_CONTROL_DATA,
1021 					 false);
1022 		ret = dwc3_ep0_start_trans(dep);
1023 	} else if (IS_ALIGNED(req->request.length, dep->endpoint.maxpacket) &&
1024 		   req->request.length && req->request.zero) {
1025 
1026 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
1027 				&req->request, dep->number);
1028 		if (ret)
1029 			return;
1030 
1031 		/* prepare normal TRB */
1032 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
1033 					 req->request.length,
1034 					 DWC3_TRBCTL_CONTROL_DATA,
1035 					 true);
1036 
1037 		req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1];
1038 
1039 		if (!req->direction)
1040 			trb_length = dep->endpoint.maxpacket;
1041 
1042 		/* Now prepare one extra TRB to align transfer size */
1043 		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr,
1044 					 trb_length, DWC3_TRBCTL_CONTROL_DATA,
1045 					 false);
1046 		ret = dwc3_ep0_start_trans(dep);
1047 	} else {
1048 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
1049 				&req->request, dep->number);
1050 		if (ret)
1051 			return;
1052 
1053 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
1054 				req->request.length, DWC3_TRBCTL_CONTROL_DATA,
1055 				false);
1056 
1057 		req->trb = &dwc->ep0_trb[dep->trb_enqueue];
1058 
1059 		ret = dwc3_ep0_start_trans(dep);
1060 	}
1061 
1062 	WARN_ON(ret < 0);
1063 }
1064 
1065 static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
1066 {
1067 	struct dwc3		*dwc = dep->dwc;
1068 	u32			type;
1069 
1070 	type = dwc->three_stage_setup ? DWC3_TRBCTL_CONTROL_STATUS3
1071 		: DWC3_TRBCTL_CONTROL_STATUS2;
1072 
1073 	dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 0, type, false);
1074 	return dwc3_ep0_start_trans(dep);
1075 }
1076 
1077 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)
1078 {
1079 	WARN_ON(dwc3_ep0_start_control_status(dep));
1080 }
1081 
1082 static void dwc3_ep0_do_control_status(struct dwc3 *dwc,
1083 		const struct dwc3_event_depevt *event)
1084 {
1085 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
1086 
1087 	__dwc3_ep0_do_control_status(dwc, dep);
1088 }
1089 
1090 void dwc3_ep0_send_delayed_status(struct dwc3 *dwc)
1091 {
1092 	unsigned int direction = !dwc->ep0_expect_in;
1093 
1094 	dwc->delayed_status = false;
1095 	dwc->clear_stall_protocol = 0;
1096 
1097 	if (dwc->ep0state != EP0_STATUS_PHASE)
1098 		return;
1099 
1100 	__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
1101 }
1102 
1103 void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep)
1104 {
1105 	struct dwc3_gadget_ep_cmd_params params;
1106 	u32			cmd;
1107 	int			ret;
1108 
1109 	/*
1110 	 * For status/DATA OUT stage, TRB will be queued on ep0 out
1111 	 * endpoint for which resource index is zero. Hence allow
1112 	 * queuing ENDXFER command for ep0 out endpoint.
1113 	 */
1114 	if (!dep->resource_index && dep->number)
1115 		return;
1116 
1117 	cmd = DWC3_DEPCMD_ENDTRANSFER;
1118 	cmd |= DWC3_DEPCMD_CMDIOC;
1119 	cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
1120 	memset(&params, 0, sizeof(params));
1121 	ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
1122 	WARN_ON_ONCE(ret);
1123 	dep->resource_index = 0;
1124 }
1125 
1126 static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
1127 		const struct dwc3_event_depevt *event)
1128 {
1129 	switch (event->status) {
1130 	case DEPEVT_STATUS_CONTROL_DATA:
1131 		if (!dwc->softconnect || !dwc->connected)
1132 			return;
1133 		/*
1134 		 * We already have a DATA transfer in the controller's cache,
1135 		 * if we receive a XferNotReady(DATA) we will ignore it, unless
1136 		 * it's for the wrong direction.
1137 		 *
1138 		 * In that case, we must issue END_TRANSFER command to the Data
1139 		 * Phase we already have started and issue SetStall on the
1140 		 * control endpoint.
1141 		 */
1142 		if (dwc->ep0_expect_in != event->endpoint_number) {
1143 			struct dwc3_ep	*dep = dwc->eps[dwc->ep0_expect_in];
1144 
1145 			dev_err(dwc->dev, "unexpected direction for Data Phase\n");
1146 			dwc3_ep0_end_control_data(dwc, dep);
1147 			dwc3_ep0_stall_and_restart(dwc);
1148 			return;
1149 		}
1150 
1151 		break;
1152 
1153 	case DEPEVT_STATUS_CONTROL_STATUS:
1154 		if (dwc->ep0_next_event != DWC3_EP0_NRDY_STATUS)
1155 			return;
1156 
1157 		if (dwc->setup_packet_pending) {
1158 			dwc3_ep0_stall_and_restart(dwc);
1159 			return;
1160 		}
1161 
1162 		dwc->ep0state = EP0_STATUS_PHASE;
1163 
1164 		if (dwc->delayed_status) {
1165 			struct dwc3_ep *dep = dwc->eps[0];
1166 
1167 			WARN_ON_ONCE(event->endpoint_number != 1);
1168 			/*
1169 			 * We should handle the delay STATUS phase here if the
1170 			 * request for handling delay STATUS has been queued
1171 			 * into the list.
1172 			 */
1173 			if (!list_empty(&dep->pending_list)) {
1174 				dwc->delayed_status = false;
1175 				usb_gadget_set_state(dwc->gadget,
1176 						     USB_STATE_CONFIGURED);
1177 				dwc3_ep0_do_control_status(dwc, event);
1178 			}
1179 
1180 			return;
1181 		}
1182 
1183 		dwc3_ep0_do_control_status(dwc, event);
1184 	}
1185 }
1186 
1187 void dwc3_ep0_interrupt(struct dwc3 *dwc,
1188 		const struct dwc3_event_depevt *event)
1189 {
1190 	struct dwc3_ep	*dep = dwc->eps[event->endpoint_number];
1191 	u8		cmd;
1192 
1193 	switch (event->endpoint_event) {
1194 	case DWC3_DEPEVT_XFERCOMPLETE:
1195 		dwc3_ep0_xfer_complete(dwc, event);
1196 		break;
1197 
1198 	case DWC3_DEPEVT_XFERNOTREADY:
1199 		dwc3_ep0_xfernotready(dwc, event);
1200 		break;
1201 
1202 	case DWC3_DEPEVT_XFERINPROGRESS:
1203 	case DWC3_DEPEVT_RXTXFIFOEVT:
1204 	case DWC3_DEPEVT_STREAMEVT:
1205 		break;
1206 	case DWC3_DEPEVT_EPCMDCMPLT:
1207 		cmd = DEPEVT_PARAMETER_CMD(event->parameters);
1208 
1209 		if (cmd == DWC3_DEPCMD_ENDTRANSFER) {
1210 			dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;
1211 			dep->flags &= ~DWC3_EP_TRANSFER_STARTED;
1212 		}
1213 		break;
1214 	default:
1215 		dev_err(dwc->dev, "unknown endpoint event %d\n", event->endpoint_event);
1216 		break;
1217 	}
1218 }
1219