xref: /linux/drivers/usb/dwc3/ep0.c (revision 44f57d78)
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 - http://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 
34 static void dwc3_ep0_prepare_one_trb(struct dwc3_ep *dep,
35 		dma_addr_t buf_dma, u32 len, u32 type, bool chain)
36 {
37 	struct dwc3_trb			*trb;
38 	struct dwc3			*dwc;
39 
40 	dwc = dep->dwc;
41 	trb = &dwc->ep0_trb[dep->trb_enqueue];
42 
43 	if (chain)
44 		dep->trb_enqueue++;
45 
46 	trb->bpl = lower_32_bits(buf_dma);
47 	trb->bph = upper_32_bits(buf_dma);
48 	trb->size = len;
49 	trb->ctrl = type;
50 
51 	trb->ctrl |= (DWC3_TRB_CTRL_HWO
52 			| DWC3_TRB_CTRL_ISP_IMI);
53 
54 	if (chain)
55 		trb->ctrl |= DWC3_TRB_CTRL_CHN;
56 	else
57 		trb->ctrl |= (DWC3_TRB_CTRL_IOC
58 				| DWC3_TRB_CTRL_LST);
59 
60 	trace_dwc3_prepare_trb(dep, trb);
61 }
62 
63 static int dwc3_ep0_start_trans(struct dwc3_ep *dep)
64 {
65 	struct dwc3_gadget_ep_cmd_params params;
66 	struct dwc3			*dwc;
67 	int				ret;
68 
69 	if (dep->flags & DWC3_EP_TRANSFER_STARTED)
70 		return 0;
71 
72 	dwc = dep->dwc;
73 
74 	memset(&params, 0, sizeof(params));
75 	params.param0 = upper_32_bits(dwc->ep0_trb_addr);
76 	params.param1 = lower_32_bits(dwc->ep0_trb_addr);
77 
78 	ret = dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_STARTTRANSFER, &params);
79 	if (ret < 0)
80 		return ret;
81 
82 	dwc->ep0_next_event = DWC3_EP0_COMPLETE;
83 
84 	return 0;
85 }
86 
87 static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep,
88 		struct dwc3_request *req)
89 {
90 	struct dwc3		*dwc = dep->dwc;
91 
92 	req->request.actual	= 0;
93 	req->request.status	= -EINPROGRESS;
94 	req->epnum		= dep->number;
95 
96 	list_add_tail(&req->list, &dep->pending_list);
97 
98 	/*
99 	 * Gadget driver might not be quick enough to queue a request
100 	 * before we get a Transfer Not Ready event on this endpoint.
101 	 *
102 	 * In that case, we will set DWC3_EP_PENDING_REQUEST. When that
103 	 * flag is set, it's telling us that as soon as Gadget queues the
104 	 * required request, we should kick the transfer here because the
105 	 * IRQ we were waiting for is long gone.
106 	 */
107 	if (dep->flags & DWC3_EP_PENDING_REQUEST) {
108 		unsigned	direction;
109 
110 		direction = !!(dep->flags & DWC3_EP0_DIR_IN);
111 
112 		if (dwc->ep0state != EP0_DATA_PHASE) {
113 			dev_WARN(dwc->dev, "Unexpected pending request\n");
114 			return 0;
115 		}
116 
117 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
118 
119 		dep->flags &= ~(DWC3_EP_PENDING_REQUEST |
120 				DWC3_EP0_DIR_IN);
121 
122 		return 0;
123 	}
124 
125 	/*
126 	 * In case gadget driver asked us to delay the STATUS phase,
127 	 * handle it here.
128 	 */
129 	if (dwc->delayed_status) {
130 		unsigned	direction;
131 
132 		direction = !dwc->ep0_expect_in;
133 		dwc->delayed_status = false;
134 		usb_gadget_set_state(&dwc->gadget, USB_STATE_CONFIGURED);
135 
136 		if (dwc->ep0state == EP0_STATUS_PHASE)
137 			__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
138 
139 		return 0;
140 	}
141 
142 	/*
143 	 * Unfortunately we have uncovered a limitation wrt the Data Phase.
144 	 *
145 	 * Section 9.4 says we can wait for the XferNotReady(DATA) event to
146 	 * come before issueing Start Transfer command, but if we do, we will
147 	 * miss situations where the host starts another SETUP phase instead of
148 	 * the DATA phase.  Such cases happen at least on TD.7.6 of the Link
149 	 * Layer Compliance Suite.
150 	 *
151 	 * The problem surfaces due to the fact that in case of back-to-back
152 	 * SETUP packets there will be no XferNotReady(DATA) generated and we
153 	 * will be stuck waiting for XferNotReady(DATA) forever.
154 	 *
155 	 * By looking at tables 9-13 and 9-14 of the Databook, we can see that
156 	 * it tells us to start Data Phase right away. It also mentions that if
157 	 * we receive a SETUP phase instead of the DATA phase, core will issue
158 	 * XferComplete for the DATA phase, before actually initiating it in
159 	 * the wire, with the TRB's status set to "SETUP_PENDING". Such status
160 	 * can only be used to print some debugging logs, as the core expects
161 	 * us to go through to the STATUS phase and start a CONTROL_STATUS TRB,
162 	 * just so it completes right away, without transferring anything and,
163 	 * only then, we can go back to the SETUP phase.
164 	 *
165 	 * Because of this scenario, SNPS decided to change the programming
166 	 * model of control transfers and support on-demand transfers only for
167 	 * the STATUS phase. To fix the issue we have now, we will always wait
168 	 * for gadget driver to queue the DATA phase's struct usb_request, then
169 	 * start it right away.
170 	 *
171 	 * If we're actually in a 2-stage transfer, we will wait for
172 	 * XferNotReady(STATUS).
173 	 */
174 	if (dwc->three_stage_setup) {
175 		unsigned        direction;
176 
177 		direction = dwc->ep0_expect_in;
178 		dwc->ep0state = EP0_DATA_PHASE;
179 
180 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
181 
182 		dep->flags &= ~DWC3_EP0_DIR_IN;
183 	}
184 
185 	return 0;
186 }
187 
188 int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
189 		gfp_t gfp_flags)
190 {
191 	struct dwc3_request		*req = to_dwc3_request(request);
192 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
193 	struct dwc3			*dwc = dep->dwc;
194 
195 	unsigned long			flags;
196 
197 	int				ret;
198 
199 	spin_lock_irqsave(&dwc->lock, flags);
200 	if (!dep->endpoint.desc) {
201 		dev_err(dwc->dev, "%s: can't queue to disabled endpoint\n",
202 				dep->name);
203 		ret = -ESHUTDOWN;
204 		goto out;
205 	}
206 
207 	/* we share one TRB for ep0/1 */
208 	if (!list_empty(&dep->pending_list)) {
209 		ret = -EBUSY;
210 		goto out;
211 	}
212 
213 	ret = __dwc3_gadget_ep0_queue(dep, req);
214 
215 out:
216 	spin_unlock_irqrestore(&dwc->lock, flags);
217 
218 	return ret;
219 }
220 
221 static void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
222 {
223 	struct dwc3_ep		*dep;
224 
225 	/* reinitialize physical ep1 */
226 	dep = dwc->eps[1];
227 	dep->flags = DWC3_EP_ENABLED;
228 
229 	/* stall is always issued on EP0 */
230 	dep = dwc->eps[0];
231 	__dwc3_gadget_ep_set_halt(dep, 1, false);
232 	dep->flags = DWC3_EP_ENABLED;
233 	dwc->delayed_status = false;
234 
235 	if (!list_empty(&dep->pending_list)) {
236 		struct dwc3_request	*req;
237 
238 		req = next_request(&dep->pending_list);
239 		dwc3_gadget_giveback(dep, req, -ECONNRESET);
240 	}
241 
242 	dwc->ep0state = EP0_SETUP_PHASE;
243 	dwc3_ep0_out_start(dwc);
244 }
245 
246 int __dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
247 {
248 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
249 	struct dwc3			*dwc = dep->dwc;
250 
251 	dwc3_ep0_stall_and_restart(dwc);
252 
253 	return 0;
254 }
255 
256 int dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
257 {
258 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
259 	struct dwc3			*dwc = dep->dwc;
260 	unsigned long			flags;
261 	int				ret;
262 
263 	spin_lock_irqsave(&dwc->lock, flags);
264 	ret = __dwc3_gadget_ep0_set_halt(ep, value);
265 	spin_unlock_irqrestore(&dwc->lock, flags);
266 
267 	return ret;
268 }
269 
270 void dwc3_ep0_out_start(struct dwc3 *dwc)
271 {
272 	struct dwc3_ep			*dep;
273 	int				ret;
274 
275 	complete(&dwc->ep0_in_setup);
276 
277 	dep = dwc->eps[0];
278 	dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 8,
279 			DWC3_TRBCTL_CONTROL_SETUP, false);
280 	ret = dwc3_ep0_start_trans(dep);
281 	WARN_ON(ret < 0);
282 }
283 
284 static struct dwc3_ep *dwc3_wIndex_to_dep(struct dwc3 *dwc, __le16 wIndex_le)
285 {
286 	struct dwc3_ep		*dep;
287 	u32			windex = le16_to_cpu(wIndex_le);
288 	u32			epnum;
289 
290 	epnum = (windex & USB_ENDPOINT_NUMBER_MASK) << 1;
291 	if ((windex & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN)
292 		epnum |= 1;
293 
294 	dep = dwc->eps[epnum];
295 	if (dep->flags & DWC3_EP_ENABLED)
296 		return dep;
297 
298 	return NULL;
299 }
300 
301 static void dwc3_ep0_status_cmpl(struct usb_ep *ep, struct usb_request *req)
302 {
303 }
304 /*
305  * ch 9.4.5
306  */
307 static int dwc3_ep0_handle_status(struct dwc3 *dwc,
308 		struct usb_ctrlrequest *ctrl)
309 {
310 	struct dwc3_ep		*dep;
311 	u32			recip;
312 	u32			value;
313 	u32			reg;
314 	u16			usb_status = 0;
315 	__le16			*response_pkt;
316 
317 	/* We don't support PTM_STATUS */
318 	value = le16_to_cpu(ctrl->wValue);
319 	if (value != 0)
320 		return -EINVAL;
321 
322 	recip = ctrl->bRequestType & USB_RECIP_MASK;
323 	switch (recip) {
324 	case USB_RECIP_DEVICE:
325 		/*
326 		 * LTM will be set once we know how to set this in HW.
327 		 */
328 		usb_status |= dwc->gadget.is_selfpowered;
329 
330 		if ((dwc->speed == DWC3_DSTS_SUPERSPEED) ||
331 		    (dwc->speed == DWC3_DSTS_SUPERSPEED_PLUS)) {
332 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
333 			if (reg & DWC3_DCTL_INITU1ENA)
334 				usb_status |= 1 << USB_DEV_STAT_U1_ENABLED;
335 			if (reg & DWC3_DCTL_INITU2ENA)
336 				usb_status |= 1 << USB_DEV_STAT_U2_ENABLED;
337 		}
338 
339 		break;
340 
341 	case USB_RECIP_INTERFACE:
342 		/*
343 		 * Function Remote Wake Capable	D0
344 		 * Function Remote Wakeup	D1
345 		 */
346 		break;
347 
348 	case USB_RECIP_ENDPOINT:
349 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
350 		if (!dep)
351 			return -EINVAL;
352 
353 		if (dep->flags & DWC3_EP_STALL)
354 			usb_status = 1 << USB_ENDPOINT_HALT;
355 		break;
356 	default:
357 		return -EINVAL;
358 	}
359 
360 	response_pkt = (__le16 *) dwc->setup_buf;
361 	*response_pkt = cpu_to_le16(usb_status);
362 
363 	dep = dwc->eps[0];
364 	dwc->ep0_usb_req.dep = dep;
365 	dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
366 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
367 	dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
368 
369 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
370 }
371 
372 static int dwc3_ep0_handle_u1(struct dwc3 *dwc, enum usb_device_state state,
373 		int set)
374 {
375 	u32 reg;
376 
377 	if (state != USB_STATE_CONFIGURED)
378 		return -EINVAL;
379 	if ((dwc->speed != DWC3_DSTS_SUPERSPEED) &&
380 			(dwc->speed != DWC3_DSTS_SUPERSPEED_PLUS))
381 		return -EINVAL;
382 
383 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
384 	if (set)
385 		reg |= DWC3_DCTL_INITU1ENA;
386 	else
387 		reg &= ~DWC3_DCTL_INITU1ENA;
388 	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
389 
390 	return 0;
391 }
392 
393 static int dwc3_ep0_handle_u2(struct dwc3 *dwc, enum usb_device_state state,
394 		int set)
395 {
396 	u32 reg;
397 
398 
399 	if (state != USB_STATE_CONFIGURED)
400 		return -EINVAL;
401 	if ((dwc->speed != DWC3_DSTS_SUPERSPEED) &&
402 			(dwc->speed != DWC3_DSTS_SUPERSPEED_PLUS))
403 		return -EINVAL;
404 
405 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
406 	if (set)
407 		reg |= DWC3_DCTL_INITU2ENA;
408 	else
409 		reg &= ~DWC3_DCTL_INITU2ENA;
410 	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
411 
412 	return 0;
413 }
414 
415 static int dwc3_ep0_handle_test(struct dwc3 *dwc, enum usb_device_state state,
416 		u32 wIndex, int set)
417 {
418 	if ((wIndex & 0xff) != 0)
419 		return -EINVAL;
420 	if (!set)
421 		return -EINVAL;
422 
423 	switch (wIndex >> 8) {
424 	case TEST_J:
425 	case TEST_K:
426 	case TEST_SE0_NAK:
427 	case TEST_PACKET:
428 	case TEST_FORCE_EN:
429 		dwc->test_mode_nr = wIndex >> 8;
430 		dwc->test_mode = true;
431 		break;
432 	default:
433 		return -EINVAL;
434 	}
435 
436 	return 0;
437 }
438 
439 static int dwc3_ep0_handle_device(struct dwc3 *dwc,
440 		struct usb_ctrlrequest *ctrl, int set)
441 {
442 	enum usb_device_state	state;
443 	u32			wValue;
444 	u32			wIndex;
445 	int			ret = 0;
446 
447 	wValue = le16_to_cpu(ctrl->wValue);
448 	wIndex = le16_to_cpu(ctrl->wIndex);
449 	state = dwc->gadget.state;
450 
451 	switch (wValue) {
452 	case USB_DEVICE_REMOTE_WAKEUP:
453 		break;
454 	/*
455 	 * 9.4.1 says only only for SS, in AddressState only for
456 	 * default control pipe
457 	 */
458 	case USB_DEVICE_U1_ENABLE:
459 		ret = dwc3_ep0_handle_u1(dwc, state, set);
460 		break;
461 	case USB_DEVICE_U2_ENABLE:
462 		ret = dwc3_ep0_handle_u2(dwc, state, set);
463 		break;
464 	case USB_DEVICE_LTM_ENABLE:
465 		ret = -EINVAL;
466 		break;
467 	case USB_DEVICE_TEST_MODE:
468 		ret = dwc3_ep0_handle_test(dwc, state, wIndex, set);
469 		break;
470 	default:
471 		ret = -EINVAL;
472 	}
473 
474 	return ret;
475 }
476 
477 static int dwc3_ep0_handle_intf(struct dwc3 *dwc,
478 		struct usb_ctrlrequest *ctrl, int set)
479 {
480 	u32			wValue;
481 	int			ret = 0;
482 
483 	wValue = le16_to_cpu(ctrl->wValue);
484 
485 	switch (wValue) {
486 	case USB_INTRF_FUNC_SUSPEND:
487 		/*
488 		 * REVISIT: Ideally we would enable some low power mode here,
489 		 * however it's unclear what we should be doing here.
490 		 *
491 		 * For now, we're not doing anything, just making sure we return
492 		 * 0 so USB Command Verifier tests pass without any errors.
493 		 */
494 		break;
495 	default:
496 		ret = -EINVAL;
497 	}
498 
499 	return ret;
500 }
501 
502 static int dwc3_ep0_handle_endpoint(struct dwc3 *dwc,
503 		struct usb_ctrlrequest *ctrl, int set)
504 {
505 	struct dwc3_ep		*dep;
506 	u32			wValue;
507 	int			ret;
508 
509 	wValue = le16_to_cpu(ctrl->wValue);
510 
511 	switch (wValue) {
512 	case USB_ENDPOINT_HALT:
513 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
514 		if (!dep)
515 			return -EINVAL;
516 
517 		if (set == 0 && (dep->flags & DWC3_EP_WEDGE))
518 			break;
519 
520 		ret = __dwc3_gadget_ep_set_halt(dep, set, true);
521 		if (ret)
522 			return -EINVAL;
523 		break;
524 	default:
525 		return -EINVAL;
526 	}
527 
528 	return 0;
529 }
530 
531 static int dwc3_ep0_handle_feature(struct dwc3 *dwc,
532 		struct usb_ctrlrequest *ctrl, int set)
533 {
534 	u32			recip;
535 	int			ret;
536 
537 	recip = ctrl->bRequestType & USB_RECIP_MASK;
538 
539 	switch (recip) {
540 	case USB_RECIP_DEVICE:
541 		ret = dwc3_ep0_handle_device(dwc, ctrl, set);
542 		break;
543 	case USB_RECIP_INTERFACE:
544 		ret = dwc3_ep0_handle_intf(dwc, ctrl, set);
545 		break;
546 	case USB_RECIP_ENDPOINT:
547 		ret = dwc3_ep0_handle_endpoint(dwc, ctrl, set);
548 		break;
549 	default:
550 		ret = -EINVAL;
551 	}
552 
553 	return ret;
554 }
555 
556 static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
557 {
558 	enum usb_device_state state = dwc->gadget.state;
559 	u32 addr;
560 	u32 reg;
561 
562 	addr = le16_to_cpu(ctrl->wValue);
563 	if (addr > 127) {
564 		dev_err(dwc->dev, "invalid device address %d\n", addr);
565 		return -EINVAL;
566 	}
567 
568 	if (state == USB_STATE_CONFIGURED) {
569 		dev_err(dwc->dev, "can't SetAddress() from Configured State\n");
570 		return -EINVAL;
571 	}
572 
573 	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
574 	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
575 	reg |= DWC3_DCFG_DEVADDR(addr);
576 	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
577 
578 	if (addr)
579 		usb_gadget_set_state(&dwc->gadget, USB_STATE_ADDRESS);
580 	else
581 		usb_gadget_set_state(&dwc->gadget, USB_STATE_DEFAULT);
582 
583 	return 0;
584 }
585 
586 static int dwc3_ep0_delegate_req(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
587 {
588 	int ret;
589 
590 	spin_unlock(&dwc->lock);
591 	ret = dwc->gadget_driver->setup(&dwc->gadget, ctrl);
592 	spin_lock(&dwc->lock);
593 	return ret;
594 }
595 
596 static int dwc3_ep0_set_config(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
597 {
598 	enum usb_device_state state = dwc->gadget.state;
599 	u32 cfg;
600 	int ret;
601 	u32 reg;
602 
603 	cfg = le16_to_cpu(ctrl->wValue);
604 
605 	switch (state) {
606 	case USB_STATE_DEFAULT:
607 		return -EINVAL;
608 
609 	case USB_STATE_ADDRESS:
610 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
611 		/* if the cfg matches and the cfg is non zero */
612 		if (cfg && (!ret || (ret == USB_GADGET_DELAYED_STATUS))) {
613 
614 			/*
615 			 * only change state if set_config has already
616 			 * been processed. If gadget driver returns
617 			 * USB_GADGET_DELAYED_STATUS, we will wait
618 			 * to change the state on the next usb_ep_queue()
619 			 */
620 			if (ret == 0)
621 				usb_gadget_set_state(&dwc->gadget,
622 						USB_STATE_CONFIGURED);
623 
624 			/*
625 			 * Enable transition to U1/U2 state when
626 			 * nothing is pending from application.
627 			 */
628 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
629 			reg |= (DWC3_DCTL_ACCEPTU1ENA | DWC3_DCTL_ACCEPTU2ENA);
630 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
631 		}
632 		break;
633 
634 	case USB_STATE_CONFIGURED:
635 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
636 		if (!cfg && !ret)
637 			usb_gadget_set_state(&dwc->gadget,
638 					USB_STATE_ADDRESS);
639 		break;
640 	default:
641 		ret = -EINVAL;
642 	}
643 	return ret;
644 }
645 
646 static void dwc3_ep0_set_sel_cmpl(struct usb_ep *ep, struct usb_request *req)
647 {
648 	struct dwc3_ep	*dep = to_dwc3_ep(ep);
649 	struct dwc3	*dwc = dep->dwc;
650 
651 	u32		param = 0;
652 	u32		reg;
653 
654 	struct timing {
655 		u8	u1sel;
656 		u8	u1pel;
657 		__le16	u2sel;
658 		__le16	u2pel;
659 	} __packed timing;
660 
661 	int		ret;
662 
663 	memcpy(&timing, req->buf, sizeof(timing));
664 
665 	dwc->u1sel = timing.u1sel;
666 	dwc->u1pel = timing.u1pel;
667 	dwc->u2sel = le16_to_cpu(timing.u2sel);
668 	dwc->u2pel = le16_to_cpu(timing.u2pel);
669 
670 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
671 	if (reg & DWC3_DCTL_INITU2ENA)
672 		param = dwc->u2pel;
673 	if (reg & DWC3_DCTL_INITU1ENA)
674 		param = dwc->u1pel;
675 
676 	/*
677 	 * According to Synopsys Databook, if parameter is
678 	 * greater than 125, a value of zero should be
679 	 * programmed in the register.
680 	 */
681 	if (param > 125)
682 		param = 0;
683 
684 	/* now that we have the time, issue DGCMD Set Sel */
685 	ret = dwc3_send_gadget_generic_command(dwc,
686 			DWC3_DGCMD_SET_PERIODIC_PAR, param);
687 	WARN_ON(ret < 0);
688 }
689 
690 static int dwc3_ep0_set_sel(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
691 {
692 	struct dwc3_ep	*dep;
693 	enum usb_device_state state = dwc->gadget.state;
694 	u16		wLength;
695 
696 	if (state == USB_STATE_DEFAULT)
697 		return -EINVAL;
698 
699 	wLength = le16_to_cpu(ctrl->wLength);
700 
701 	if (wLength != 6) {
702 		dev_err(dwc->dev, "Set SEL should be 6 bytes, got %d\n",
703 				wLength);
704 		return -EINVAL;
705 	}
706 
707 	/*
708 	 * To handle Set SEL we need to receive 6 bytes from Host. So let's
709 	 * queue a usb_request for 6 bytes.
710 	 *
711 	 * Remember, though, this controller can't handle non-wMaxPacketSize
712 	 * aligned transfers on the OUT direction, so we queue a request for
713 	 * wMaxPacketSize instead.
714 	 */
715 	dep = dwc->eps[0];
716 	dwc->ep0_usb_req.dep = dep;
717 	dwc->ep0_usb_req.request.length = dep->endpoint.maxpacket;
718 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
719 	dwc->ep0_usb_req.request.complete = dwc3_ep0_set_sel_cmpl;
720 
721 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
722 }
723 
724 static int dwc3_ep0_set_isoch_delay(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
725 {
726 	u16		wLength;
727 	u16		wValue;
728 	u16		wIndex;
729 
730 	wValue = le16_to_cpu(ctrl->wValue);
731 	wLength = le16_to_cpu(ctrl->wLength);
732 	wIndex = le16_to_cpu(ctrl->wIndex);
733 
734 	if (wIndex || wLength)
735 		return -EINVAL;
736 
737 	dwc->gadget.isoch_delay = wValue;
738 
739 	return 0;
740 }
741 
742 static int dwc3_ep0_std_request(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
743 {
744 	int ret;
745 
746 	switch (ctrl->bRequest) {
747 	case USB_REQ_GET_STATUS:
748 		ret = dwc3_ep0_handle_status(dwc, ctrl);
749 		break;
750 	case USB_REQ_CLEAR_FEATURE:
751 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 0);
752 		break;
753 	case USB_REQ_SET_FEATURE:
754 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 1);
755 		break;
756 	case USB_REQ_SET_ADDRESS:
757 		ret = dwc3_ep0_set_address(dwc, ctrl);
758 		break;
759 	case USB_REQ_SET_CONFIGURATION:
760 		ret = dwc3_ep0_set_config(dwc, ctrl);
761 		break;
762 	case USB_REQ_SET_SEL:
763 		ret = dwc3_ep0_set_sel(dwc, ctrl);
764 		break;
765 	case USB_REQ_SET_ISOCH_DELAY:
766 		ret = dwc3_ep0_set_isoch_delay(dwc, ctrl);
767 		break;
768 	default:
769 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
770 		break;
771 	}
772 
773 	return ret;
774 }
775 
776 static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
777 		const struct dwc3_event_depevt *event)
778 {
779 	struct usb_ctrlrequest *ctrl = (void *) dwc->ep0_trb;
780 	int ret = -EINVAL;
781 	u32 len;
782 
783 	if (!dwc->gadget_driver)
784 		goto out;
785 
786 	trace_dwc3_ctrl_req(ctrl);
787 
788 	len = le16_to_cpu(ctrl->wLength);
789 	if (!len) {
790 		dwc->three_stage_setup = false;
791 		dwc->ep0_expect_in = false;
792 		dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
793 	} else {
794 		dwc->three_stage_setup = true;
795 		dwc->ep0_expect_in = !!(ctrl->bRequestType & USB_DIR_IN);
796 		dwc->ep0_next_event = DWC3_EP0_NRDY_DATA;
797 	}
798 
799 	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
800 		ret = dwc3_ep0_std_request(dwc, ctrl);
801 	else
802 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
803 
804 	if (ret == USB_GADGET_DELAYED_STATUS)
805 		dwc->delayed_status = true;
806 
807 out:
808 	if (ret < 0)
809 		dwc3_ep0_stall_and_restart(dwc);
810 }
811 
812 static void dwc3_ep0_complete_data(struct dwc3 *dwc,
813 		const struct dwc3_event_depevt *event)
814 {
815 	struct dwc3_request	*r;
816 	struct usb_request	*ur;
817 	struct dwc3_trb		*trb;
818 	struct dwc3_ep		*ep0;
819 	u32			transferred = 0;
820 	u32			status;
821 	u32			length;
822 	u8			epnum;
823 
824 	epnum = event->endpoint_number;
825 	ep0 = dwc->eps[0];
826 
827 	dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
828 	trb = dwc->ep0_trb;
829 	trace_dwc3_complete_trb(ep0, trb);
830 
831 	r = next_request(&ep0->pending_list);
832 	if (!r)
833 		return;
834 
835 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
836 	if (status == DWC3_TRBSTS_SETUP_PENDING) {
837 		dwc->setup_packet_pending = true;
838 		if (r)
839 			dwc3_gadget_giveback(ep0, r, -ECONNRESET);
840 
841 		return;
842 	}
843 
844 	ur = &r->request;
845 
846 	length = trb->size & DWC3_TRB_SIZE_MASK;
847 	transferred = ur->length - length;
848 	ur->actual += transferred;
849 
850 	if ((IS_ALIGNED(ur->length, ep0->endpoint.maxpacket) &&
851 	     ur->length && ur->zero) || dwc->ep0_bounced) {
852 		trb++;
853 		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
854 		trace_dwc3_complete_trb(ep0, trb);
855 
856 		if (r->direction)
857 			dwc->eps[1]->trb_enqueue = 0;
858 		else
859 			dwc->eps[0]->trb_enqueue = 0;
860 
861 		dwc->ep0_bounced = false;
862 	}
863 
864 	if ((epnum & 1) && ur->actual < ur->length)
865 		dwc3_ep0_stall_and_restart(dwc);
866 	else
867 		dwc3_gadget_giveback(ep0, r, 0);
868 }
869 
870 static void dwc3_ep0_complete_status(struct dwc3 *dwc,
871 		const struct dwc3_event_depevt *event)
872 {
873 	struct dwc3_request	*r;
874 	struct dwc3_ep		*dep;
875 	struct dwc3_trb		*trb;
876 	u32			status;
877 
878 	dep = dwc->eps[0];
879 	trb = dwc->ep0_trb;
880 
881 	trace_dwc3_complete_trb(dep, trb);
882 
883 	if (!list_empty(&dep->pending_list)) {
884 		r = next_request(&dep->pending_list);
885 
886 		dwc3_gadget_giveback(dep, r, 0);
887 	}
888 
889 	if (dwc->test_mode) {
890 		int ret;
891 
892 		ret = dwc3_gadget_set_test_mode(dwc, dwc->test_mode_nr);
893 		if (ret < 0) {
894 			dev_err(dwc->dev, "invalid test #%d\n",
895 					dwc->test_mode_nr);
896 			dwc3_ep0_stall_and_restart(dwc);
897 			return;
898 		}
899 	}
900 
901 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
902 	if (status == DWC3_TRBSTS_SETUP_PENDING)
903 		dwc->setup_packet_pending = true;
904 
905 	dwc->ep0state = EP0_SETUP_PHASE;
906 	dwc3_ep0_out_start(dwc);
907 }
908 
909 static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
910 			const struct dwc3_event_depevt *event)
911 {
912 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
913 
914 	dep->flags &= ~DWC3_EP_TRANSFER_STARTED;
915 	dep->resource_index = 0;
916 	dwc->setup_packet_pending = false;
917 
918 	switch (dwc->ep0state) {
919 	case EP0_SETUP_PHASE:
920 		dwc3_ep0_inspect_setup(dwc, event);
921 		break;
922 
923 	case EP0_DATA_PHASE:
924 		dwc3_ep0_complete_data(dwc, event);
925 		break;
926 
927 	case EP0_STATUS_PHASE:
928 		dwc3_ep0_complete_status(dwc, event);
929 		break;
930 	default:
931 		WARN(true, "UNKNOWN ep0state %d\n", dwc->ep0state);
932 	}
933 }
934 
935 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
936 		struct dwc3_ep *dep, struct dwc3_request *req)
937 {
938 	int			ret;
939 
940 	req->direction = !!dep->number;
941 
942 	if (req->request.length == 0) {
943 		dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 0,
944 				DWC3_TRBCTL_CONTROL_DATA, false);
945 		ret = dwc3_ep0_start_trans(dep);
946 	} else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
947 			&& (dep->number == 0)) {
948 		u32	maxpacket;
949 		u32	rem;
950 
951 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
952 				&req->request, dep->number);
953 		if (ret)
954 			return;
955 
956 		maxpacket = dep->endpoint.maxpacket;
957 		rem = req->request.length % maxpacket;
958 		dwc->ep0_bounced = true;
959 
960 		/* prepare normal TRB */
961 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
962 					 req->request.length,
963 					 DWC3_TRBCTL_CONTROL_DATA,
964 					 true);
965 
966 		req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1];
967 
968 		/* Now prepare one extra TRB to align transfer size */
969 		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr,
970 					 maxpacket - rem,
971 					 DWC3_TRBCTL_CONTROL_DATA,
972 					 false);
973 		ret = dwc3_ep0_start_trans(dep);
974 	} else if (IS_ALIGNED(req->request.length, dep->endpoint.maxpacket) &&
975 		   req->request.length && req->request.zero) {
976 
977 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
978 				&req->request, dep->number);
979 		if (ret)
980 			return;
981 
982 		/* prepare normal TRB */
983 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
984 					 req->request.length,
985 					 DWC3_TRBCTL_CONTROL_DATA,
986 					 true);
987 
988 		req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1];
989 
990 		/* Now prepare one extra TRB to align transfer size */
991 		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr,
992 					 0, DWC3_TRBCTL_CONTROL_DATA,
993 					 false);
994 		ret = dwc3_ep0_start_trans(dep);
995 	} else {
996 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
997 				&req->request, dep->number);
998 		if (ret)
999 			return;
1000 
1001 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
1002 				req->request.length, DWC3_TRBCTL_CONTROL_DATA,
1003 				false);
1004 
1005 		req->trb = &dwc->ep0_trb[dep->trb_enqueue];
1006 
1007 		ret = dwc3_ep0_start_trans(dep);
1008 	}
1009 
1010 	WARN_ON(ret < 0);
1011 }
1012 
1013 static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
1014 {
1015 	struct dwc3		*dwc = dep->dwc;
1016 	u32			type;
1017 
1018 	type = dwc->three_stage_setup ? DWC3_TRBCTL_CONTROL_STATUS3
1019 		: DWC3_TRBCTL_CONTROL_STATUS2;
1020 
1021 	dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 0, type, false);
1022 	return dwc3_ep0_start_trans(dep);
1023 }
1024 
1025 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)
1026 {
1027 	WARN_ON(dwc3_ep0_start_control_status(dep));
1028 }
1029 
1030 static void dwc3_ep0_do_control_status(struct dwc3 *dwc,
1031 		const struct dwc3_event_depevt *event)
1032 {
1033 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
1034 
1035 	__dwc3_ep0_do_control_status(dwc, dep);
1036 }
1037 
1038 static void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep)
1039 {
1040 	struct dwc3_gadget_ep_cmd_params params;
1041 	u32			cmd;
1042 	int			ret;
1043 
1044 	if (!dep->resource_index)
1045 		return;
1046 
1047 	cmd = DWC3_DEPCMD_ENDTRANSFER;
1048 	cmd |= DWC3_DEPCMD_CMDIOC;
1049 	cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
1050 	memset(&params, 0, sizeof(params));
1051 	ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
1052 	WARN_ON_ONCE(ret);
1053 	dep->resource_index = 0;
1054 }
1055 
1056 static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
1057 		const struct dwc3_event_depevt *event)
1058 {
1059 	switch (event->status) {
1060 	case DEPEVT_STATUS_CONTROL_DATA:
1061 		/*
1062 		 * We already have a DATA transfer in the controller's cache,
1063 		 * if we receive a XferNotReady(DATA) we will ignore it, unless
1064 		 * it's for the wrong direction.
1065 		 *
1066 		 * In that case, we must issue END_TRANSFER command to the Data
1067 		 * Phase we already have started and issue SetStall on the
1068 		 * control endpoint.
1069 		 */
1070 		if (dwc->ep0_expect_in != event->endpoint_number) {
1071 			struct dwc3_ep	*dep = dwc->eps[dwc->ep0_expect_in];
1072 
1073 			dev_err(dwc->dev, "unexpected direction for Data Phase\n");
1074 			dwc3_ep0_end_control_data(dwc, dep);
1075 			dwc3_ep0_stall_and_restart(dwc);
1076 			return;
1077 		}
1078 
1079 		break;
1080 
1081 	case DEPEVT_STATUS_CONTROL_STATUS:
1082 		if (dwc->ep0_next_event != DWC3_EP0_NRDY_STATUS)
1083 			return;
1084 
1085 		dwc->ep0state = EP0_STATUS_PHASE;
1086 
1087 		if (dwc->delayed_status) {
1088 			struct dwc3_ep *dep = dwc->eps[0];
1089 
1090 			WARN_ON_ONCE(event->endpoint_number != 1);
1091 			/*
1092 			 * We should handle the delay STATUS phase here if the
1093 			 * request for handling delay STATUS has been queued
1094 			 * into the list.
1095 			 */
1096 			if (!list_empty(&dep->pending_list)) {
1097 				dwc->delayed_status = false;
1098 				usb_gadget_set_state(&dwc->gadget,
1099 						     USB_STATE_CONFIGURED);
1100 				dwc3_ep0_do_control_status(dwc, event);
1101 			}
1102 
1103 			return;
1104 		}
1105 
1106 		dwc3_ep0_do_control_status(dwc, event);
1107 	}
1108 }
1109 
1110 void dwc3_ep0_interrupt(struct dwc3 *dwc,
1111 		const struct dwc3_event_depevt *event)
1112 {
1113 	switch (event->endpoint_event) {
1114 	case DWC3_DEPEVT_XFERCOMPLETE:
1115 		dwc3_ep0_xfer_complete(dwc, event);
1116 		break;
1117 
1118 	case DWC3_DEPEVT_XFERNOTREADY:
1119 		dwc3_ep0_xfernotready(dwc, event);
1120 		break;
1121 
1122 	case DWC3_DEPEVT_XFERINPROGRESS:
1123 	case DWC3_DEPEVT_RXTXFIFOEVT:
1124 	case DWC3_DEPEVT_STREAMEVT:
1125 	case DWC3_DEPEVT_EPCMDCMPLT:
1126 		break;
1127 	}
1128 }
1129