xref: /openbmc/linux/drivers/usb/dwc3/ep0.c (revision 6db6b729)
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 		dwc3_gadget_giveback(dep, req, -ECONNRESET);
242 	}
243 
244 	dwc->eps[0]->trb_enqueue = 0;
245 	dwc->eps[1]->trb_enqueue = 0;
246 	dwc->ep0state = EP0_SETUP_PHASE;
247 	dwc3_ep0_out_start(dwc);
248 }
249 
250 int __dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
251 {
252 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
253 	struct dwc3			*dwc = dep->dwc;
254 
255 	dwc3_ep0_stall_and_restart(dwc);
256 
257 	return 0;
258 }
259 
260 int dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
261 {
262 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
263 	struct dwc3			*dwc = dep->dwc;
264 	unsigned long			flags;
265 	int				ret;
266 
267 	spin_lock_irqsave(&dwc->lock, flags);
268 	ret = __dwc3_gadget_ep0_set_halt(ep, value);
269 	spin_unlock_irqrestore(&dwc->lock, flags);
270 
271 	return ret;
272 }
273 
274 void dwc3_ep0_out_start(struct dwc3 *dwc)
275 {
276 	struct dwc3_ep			*dep;
277 	int				ret;
278 	int                             i;
279 
280 	complete(&dwc->ep0_in_setup);
281 
282 	dep = dwc->eps[0];
283 	dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 8,
284 			DWC3_TRBCTL_CONTROL_SETUP, false);
285 	ret = dwc3_ep0_start_trans(dep);
286 	WARN_ON(ret < 0);
287 	for (i = 2; i < DWC3_ENDPOINTS_NUM; i++) {
288 		struct dwc3_ep *dwc3_ep;
289 
290 		dwc3_ep = dwc->eps[i];
291 		if (!dwc3_ep)
292 			continue;
293 
294 		if (!(dwc3_ep->flags & DWC3_EP_DELAY_STOP))
295 			continue;
296 
297 		dwc3_ep->flags &= ~DWC3_EP_DELAY_STOP;
298 		if (dwc->connected)
299 			dwc3_stop_active_transfer(dwc3_ep, true, true);
300 		else
301 			dwc3_remove_requests(dwc, dwc3_ep, -ESHUTDOWN);
302 	}
303 }
304 
305 static struct dwc3_ep *dwc3_wIndex_to_dep(struct dwc3 *dwc, __le16 wIndex_le)
306 {
307 	struct dwc3_ep		*dep;
308 	u32			windex = le16_to_cpu(wIndex_le);
309 	u32			epnum;
310 
311 	epnum = (windex & USB_ENDPOINT_NUMBER_MASK) << 1;
312 	if ((windex & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN)
313 		epnum |= 1;
314 
315 	dep = dwc->eps[epnum];
316 	if (dep == NULL)
317 		return NULL;
318 
319 	if (dep->flags & DWC3_EP_ENABLED)
320 		return dep;
321 
322 	return NULL;
323 }
324 
325 static void dwc3_ep0_status_cmpl(struct usb_ep *ep, struct usb_request *req)
326 {
327 }
328 /*
329  * ch 9.4.5
330  */
331 static int dwc3_ep0_handle_status(struct dwc3 *dwc,
332 		struct usb_ctrlrequest *ctrl)
333 {
334 	struct dwc3_ep		*dep;
335 	u32			recip;
336 	u32			value;
337 	u32			reg;
338 	u16			usb_status = 0;
339 	__le16			*response_pkt;
340 
341 	/* We don't support PTM_STATUS */
342 	value = le16_to_cpu(ctrl->wValue);
343 	if (value != 0)
344 		return -EINVAL;
345 
346 	recip = ctrl->bRequestType & USB_RECIP_MASK;
347 	switch (recip) {
348 	case USB_RECIP_DEVICE:
349 		/*
350 		 * LTM will be set once we know how to set this in HW.
351 		 */
352 		usb_status |= dwc->gadget->is_selfpowered;
353 
354 		if ((dwc->speed == DWC3_DSTS_SUPERSPEED) ||
355 		    (dwc->speed == DWC3_DSTS_SUPERSPEED_PLUS)) {
356 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
357 			if (reg & DWC3_DCTL_INITU1ENA)
358 				usb_status |= 1 << USB_DEV_STAT_U1_ENABLED;
359 			if (reg & DWC3_DCTL_INITU2ENA)
360 				usb_status |= 1 << USB_DEV_STAT_U2_ENABLED;
361 		} else {
362 			usb_status |= dwc->gadget->wakeup_armed <<
363 					USB_DEVICE_REMOTE_WAKEUP;
364 		}
365 
366 		break;
367 
368 	case USB_RECIP_INTERFACE:
369 		/*
370 		 * Function Remote Wake Capable	D0
371 		 * Function Remote Wakeup	D1
372 		 */
373 		return dwc3_ep0_delegate_req(dwc, ctrl);
374 
375 	case USB_RECIP_ENDPOINT:
376 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
377 		if (!dep)
378 			return -EINVAL;
379 
380 		if (dep->flags & DWC3_EP_STALL)
381 			usb_status = 1 << USB_ENDPOINT_HALT;
382 		break;
383 	default:
384 		return -EINVAL;
385 	}
386 
387 	response_pkt = (__le16 *) dwc->setup_buf;
388 	*response_pkt = cpu_to_le16(usb_status);
389 
390 	dep = dwc->eps[0];
391 	dwc->ep0_usb_req.dep = dep;
392 	dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
393 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
394 	dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
395 
396 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
397 }
398 
399 static int dwc3_ep0_handle_u1(struct dwc3 *dwc, enum usb_device_state state,
400 		int set)
401 {
402 	u32 reg;
403 
404 	if (state != USB_STATE_CONFIGURED)
405 		return -EINVAL;
406 	if ((dwc->speed != DWC3_DSTS_SUPERSPEED) &&
407 			(dwc->speed != DWC3_DSTS_SUPERSPEED_PLUS))
408 		return -EINVAL;
409 	if (set && dwc->dis_u1_entry_quirk)
410 		return -EINVAL;
411 
412 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
413 	if (set)
414 		reg |= DWC3_DCTL_INITU1ENA;
415 	else
416 		reg &= ~DWC3_DCTL_INITU1ENA;
417 	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
418 
419 	return 0;
420 }
421 
422 static int dwc3_ep0_handle_u2(struct dwc3 *dwc, enum usb_device_state state,
423 		int set)
424 {
425 	u32 reg;
426 
427 
428 	if (state != USB_STATE_CONFIGURED)
429 		return -EINVAL;
430 	if ((dwc->speed != DWC3_DSTS_SUPERSPEED) &&
431 			(dwc->speed != DWC3_DSTS_SUPERSPEED_PLUS))
432 		return -EINVAL;
433 	if (set && dwc->dis_u2_entry_quirk)
434 		return -EINVAL;
435 
436 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
437 	if (set)
438 		reg |= DWC3_DCTL_INITU2ENA;
439 	else
440 		reg &= ~DWC3_DCTL_INITU2ENA;
441 	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
442 
443 	return 0;
444 }
445 
446 static int dwc3_ep0_handle_test(struct dwc3 *dwc, enum usb_device_state state,
447 		u32 wIndex, int set)
448 {
449 	if ((wIndex & 0xff) != 0)
450 		return -EINVAL;
451 	if (!set)
452 		return -EINVAL;
453 
454 	switch (wIndex >> 8) {
455 	case USB_TEST_J:
456 	case USB_TEST_K:
457 	case USB_TEST_SE0_NAK:
458 	case USB_TEST_PACKET:
459 	case USB_TEST_FORCE_ENABLE:
460 		dwc->test_mode_nr = wIndex >> 8;
461 		dwc->test_mode = true;
462 		break;
463 	default:
464 		return -EINVAL;
465 	}
466 
467 	return 0;
468 }
469 
470 static int dwc3_ep0_handle_device(struct dwc3 *dwc,
471 		struct usb_ctrlrequest *ctrl, int set)
472 {
473 	enum usb_device_state	state;
474 	u32			wValue;
475 	u32			wIndex;
476 	int			ret = 0;
477 
478 	wValue = le16_to_cpu(ctrl->wValue);
479 	wIndex = le16_to_cpu(ctrl->wIndex);
480 	state = dwc->gadget->state;
481 
482 	switch (wValue) {
483 	case USB_DEVICE_REMOTE_WAKEUP:
484 		if (dwc->wakeup_configured)
485 			dwc->gadget->wakeup_armed = set;
486 		else
487 			ret = -EINVAL;
488 		break;
489 	/*
490 	 * 9.4.1 says only for SS, in AddressState only for
491 	 * default control pipe
492 	 */
493 	case USB_DEVICE_U1_ENABLE:
494 		ret = dwc3_ep0_handle_u1(dwc, state, set);
495 		break;
496 	case USB_DEVICE_U2_ENABLE:
497 		ret = dwc3_ep0_handle_u2(dwc, state, set);
498 		break;
499 	case USB_DEVICE_LTM_ENABLE:
500 		ret = -EINVAL;
501 		break;
502 	case USB_DEVICE_TEST_MODE:
503 		ret = dwc3_ep0_handle_test(dwc, state, wIndex, set);
504 		break;
505 	default:
506 		ret = -EINVAL;
507 	}
508 
509 	return ret;
510 }
511 
512 static int dwc3_ep0_handle_intf(struct dwc3 *dwc,
513 		struct usb_ctrlrequest *ctrl, int set)
514 {
515 	u32			wValue;
516 	int			ret = 0;
517 
518 	wValue = le16_to_cpu(ctrl->wValue);
519 
520 	switch (wValue) {
521 	case USB_INTRF_FUNC_SUSPEND:
522 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
523 		break;
524 	default:
525 		ret = -EINVAL;
526 	}
527 
528 	return ret;
529 }
530 
531 static int dwc3_ep0_handle_endpoint(struct dwc3 *dwc,
532 		struct usb_ctrlrequest *ctrl, int set)
533 {
534 	struct dwc3_ep		*dep;
535 	u32			wValue;
536 	int			ret;
537 
538 	wValue = le16_to_cpu(ctrl->wValue);
539 
540 	switch (wValue) {
541 	case USB_ENDPOINT_HALT:
542 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
543 		if (!dep)
544 			return -EINVAL;
545 
546 		if (set == 0 && (dep->flags & DWC3_EP_WEDGE))
547 			break;
548 
549 		ret = __dwc3_gadget_ep_set_halt(dep, set, true);
550 		if (ret)
551 			return -EINVAL;
552 
553 		/* ClearFeature(Halt) may need delayed status */
554 		if (!set && (dep->flags & DWC3_EP_END_TRANSFER_PENDING))
555 			return USB_GADGET_DELAYED_STATUS;
556 
557 		break;
558 	default:
559 		return -EINVAL;
560 	}
561 
562 	return 0;
563 }
564 
565 static int dwc3_ep0_handle_feature(struct dwc3 *dwc,
566 		struct usb_ctrlrequest *ctrl, int set)
567 {
568 	u32			recip;
569 	int			ret;
570 
571 	recip = ctrl->bRequestType & USB_RECIP_MASK;
572 
573 	switch (recip) {
574 	case USB_RECIP_DEVICE:
575 		ret = dwc3_ep0_handle_device(dwc, ctrl, set);
576 		break;
577 	case USB_RECIP_INTERFACE:
578 		ret = dwc3_ep0_handle_intf(dwc, ctrl, set);
579 		break;
580 	case USB_RECIP_ENDPOINT:
581 		ret = dwc3_ep0_handle_endpoint(dwc, ctrl, set);
582 		break;
583 	default:
584 		ret = -EINVAL;
585 	}
586 
587 	return ret;
588 }
589 
590 static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
591 {
592 	enum usb_device_state state = dwc->gadget->state;
593 	u32 addr;
594 	u32 reg;
595 
596 	addr = le16_to_cpu(ctrl->wValue);
597 	if (addr > 127) {
598 		dev_err(dwc->dev, "invalid device address %d\n", addr);
599 		return -EINVAL;
600 	}
601 
602 	if (state == USB_STATE_CONFIGURED) {
603 		dev_err(dwc->dev, "can't SetAddress() from Configured State\n");
604 		return -EINVAL;
605 	}
606 
607 	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
608 	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
609 	reg |= DWC3_DCFG_DEVADDR(addr);
610 	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
611 
612 	if (addr)
613 		usb_gadget_set_state(dwc->gadget, USB_STATE_ADDRESS);
614 	else
615 		usb_gadget_set_state(dwc->gadget, USB_STATE_DEFAULT);
616 
617 	return 0;
618 }
619 
620 static int dwc3_ep0_delegate_req(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
621 {
622 	int ret = -EINVAL;
623 
624 	if (dwc->async_callbacks) {
625 		spin_unlock(&dwc->lock);
626 		ret = dwc->gadget_driver->setup(dwc->gadget, ctrl);
627 		spin_lock(&dwc->lock);
628 	}
629 	return ret;
630 }
631 
632 static int dwc3_ep0_set_config(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
633 {
634 	enum usb_device_state state = dwc->gadget->state;
635 	u32 cfg;
636 	int ret;
637 	u32 reg;
638 
639 	cfg = le16_to_cpu(ctrl->wValue);
640 
641 	switch (state) {
642 	case USB_STATE_DEFAULT:
643 		return -EINVAL;
644 
645 	case USB_STATE_ADDRESS:
646 		dwc3_gadget_clear_tx_fifos(dwc);
647 
648 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
649 		/* if the cfg matches and the cfg is non zero */
650 		if (cfg && (!ret || (ret == USB_GADGET_DELAYED_STATUS))) {
651 
652 			/*
653 			 * only change state if set_config has already
654 			 * been processed. If gadget driver returns
655 			 * USB_GADGET_DELAYED_STATUS, we will wait
656 			 * to change the state on the next usb_ep_queue()
657 			 */
658 			if (ret == 0)
659 				usb_gadget_set_state(dwc->gadget,
660 						USB_STATE_CONFIGURED);
661 
662 			/*
663 			 * Enable transition to U1/U2 state when
664 			 * nothing is pending from application.
665 			 */
666 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
667 			if (!dwc->dis_u1_entry_quirk)
668 				reg |= DWC3_DCTL_ACCEPTU1ENA;
669 			if (!dwc->dis_u2_entry_quirk)
670 				reg |= DWC3_DCTL_ACCEPTU2ENA;
671 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
672 		}
673 		break;
674 
675 	case USB_STATE_CONFIGURED:
676 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
677 		if (!cfg && !ret)
678 			usb_gadget_set_state(dwc->gadget,
679 					USB_STATE_ADDRESS);
680 		break;
681 	default:
682 		ret = -EINVAL;
683 	}
684 	return ret;
685 }
686 
687 static void dwc3_ep0_set_sel_cmpl(struct usb_ep *ep, struct usb_request *req)
688 {
689 	struct dwc3_ep	*dep = to_dwc3_ep(ep);
690 	struct dwc3	*dwc = dep->dwc;
691 
692 	u32		param = 0;
693 	u32		reg;
694 
695 	struct timing {
696 		u8	u1sel;
697 		u8	u1pel;
698 		__le16	u2sel;
699 		__le16	u2pel;
700 	} __packed timing;
701 
702 	int		ret;
703 
704 	memcpy(&timing, req->buf, sizeof(timing));
705 
706 	dwc->u1sel = timing.u1sel;
707 	dwc->u1pel = timing.u1pel;
708 	dwc->u2sel = le16_to_cpu(timing.u2sel);
709 	dwc->u2pel = le16_to_cpu(timing.u2pel);
710 
711 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
712 	if (reg & DWC3_DCTL_INITU2ENA)
713 		param = dwc->u2pel;
714 	if (reg & DWC3_DCTL_INITU1ENA)
715 		param = dwc->u1pel;
716 
717 	/*
718 	 * According to Synopsys Databook, if parameter is
719 	 * greater than 125, a value of zero should be
720 	 * programmed in the register.
721 	 */
722 	if (param > 125)
723 		param = 0;
724 
725 	/* now that we have the time, issue DGCMD Set Sel */
726 	ret = dwc3_send_gadget_generic_command(dwc,
727 			DWC3_DGCMD_SET_PERIODIC_PAR, param);
728 	WARN_ON(ret < 0);
729 }
730 
731 static int dwc3_ep0_set_sel(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
732 {
733 	struct dwc3_ep	*dep;
734 	enum usb_device_state state = dwc->gadget->state;
735 	u16		wLength;
736 
737 	if (state == USB_STATE_DEFAULT)
738 		return -EINVAL;
739 
740 	wLength = le16_to_cpu(ctrl->wLength);
741 
742 	if (wLength != 6) {
743 		dev_err(dwc->dev, "Set SEL should be 6 bytes, got %d\n",
744 				wLength);
745 		return -EINVAL;
746 	}
747 
748 	/*
749 	 * To handle Set SEL we need to receive 6 bytes from Host. So let's
750 	 * queue a usb_request for 6 bytes.
751 	 *
752 	 * Remember, though, this controller can't handle non-wMaxPacketSize
753 	 * aligned transfers on the OUT direction, so we queue a request for
754 	 * wMaxPacketSize instead.
755 	 */
756 	dep = dwc->eps[0];
757 	dwc->ep0_usb_req.dep = dep;
758 	dwc->ep0_usb_req.request.length = dep->endpoint.maxpacket;
759 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
760 	dwc->ep0_usb_req.request.complete = dwc3_ep0_set_sel_cmpl;
761 
762 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
763 }
764 
765 static int dwc3_ep0_set_isoch_delay(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
766 {
767 	u16		wLength;
768 	u16		wValue;
769 	u16		wIndex;
770 
771 	wValue = le16_to_cpu(ctrl->wValue);
772 	wLength = le16_to_cpu(ctrl->wLength);
773 	wIndex = le16_to_cpu(ctrl->wIndex);
774 
775 	if (wIndex || wLength)
776 		return -EINVAL;
777 
778 	dwc->gadget->isoch_delay = wValue;
779 
780 	return 0;
781 }
782 
783 static int dwc3_ep0_std_request(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
784 {
785 	int ret;
786 
787 	switch (ctrl->bRequest) {
788 	case USB_REQ_GET_STATUS:
789 		ret = dwc3_ep0_handle_status(dwc, ctrl);
790 		break;
791 	case USB_REQ_CLEAR_FEATURE:
792 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 0);
793 		break;
794 	case USB_REQ_SET_FEATURE:
795 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 1);
796 		break;
797 	case USB_REQ_SET_ADDRESS:
798 		ret = dwc3_ep0_set_address(dwc, ctrl);
799 		break;
800 	case USB_REQ_SET_CONFIGURATION:
801 		ret = dwc3_ep0_set_config(dwc, ctrl);
802 		break;
803 	case USB_REQ_SET_SEL:
804 		ret = dwc3_ep0_set_sel(dwc, ctrl);
805 		break;
806 	case USB_REQ_SET_ISOCH_DELAY:
807 		ret = dwc3_ep0_set_isoch_delay(dwc, ctrl);
808 		break;
809 	default:
810 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
811 		break;
812 	}
813 
814 	return ret;
815 }
816 
817 static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
818 		const struct dwc3_event_depevt *event)
819 {
820 	struct usb_ctrlrequest *ctrl = (void *) dwc->ep0_trb;
821 	int ret = -EINVAL;
822 	u32 len;
823 
824 	if (!dwc->gadget_driver || !dwc->softconnect || !dwc->connected)
825 		goto out;
826 
827 	trace_dwc3_ctrl_req(ctrl);
828 
829 	len = le16_to_cpu(ctrl->wLength);
830 	if (!len) {
831 		dwc->three_stage_setup = false;
832 		dwc->ep0_expect_in = false;
833 		dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
834 	} else {
835 		dwc->three_stage_setup = true;
836 		dwc->ep0_expect_in = !!(ctrl->bRequestType & USB_DIR_IN);
837 		dwc->ep0_next_event = DWC3_EP0_NRDY_DATA;
838 	}
839 
840 	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
841 		ret = dwc3_ep0_std_request(dwc, ctrl);
842 	else
843 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
844 
845 	if (ret == USB_GADGET_DELAYED_STATUS)
846 		dwc->delayed_status = true;
847 
848 out:
849 	if (ret < 0)
850 		dwc3_ep0_stall_and_restart(dwc);
851 }
852 
853 static void dwc3_ep0_complete_data(struct dwc3 *dwc,
854 		const struct dwc3_event_depevt *event)
855 {
856 	struct dwc3_request	*r;
857 	struct usb_request	*ur;
858 	struct dwc3_trb		*trb;
859 	struct dwc3_ep		*ep0;
860 	u32			transferred = 0;
861 	u32			status;
862 	u32			length;
863 	u8			epnum;
864 
865 	epnum = event->endpoint_number;
866 	ep0 = dwc->eps[0];
867 
868 	dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
869 	trb = dwc->ep0_trb;
870 	trace_dwc3_complete_trb(ep0, trb);
871 
872 	r = next_request(&ep0->pending_list);
873 	if (!r)
874 		return;
875 
876 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
877 	if (status == DWC3_TRBSTS_SETUP_PENDING) {
878 		dwc->setup_packet_pending = true;
879 		if (r)
880 			dwc3_gadget_giveback(ep0, r, -ECONNRESET);
881 
882 		return;
883 	}
884 
885 	ur = &r->request;
886 
887 	length = trb->size & DWC3_TRB_SIZE_MASK;
888 	transferred = ur->length - length;
889 	ur->actual += transferred;
890 
891 	if ((IS_ALIGNED(ur->length, ep0->endpoint.maxpacket) &&
892 	     ur->length && ur->zero) || dwc->ep0_bounced) {
893 		trb++;
894 		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
895 		trace_dwc3_complete_trb(ep0, trb);
896 
897 		if (r->direction)
898 			dwc->eps[1]->trb_enqueue = 0;
899 		else
900 			dwc->eps[0]->trb_enqueue = 0;
901 
902 		dwc->ep0_bounced = false;
903 	}
904 
905 	if ((epnum & 1) && ur->actual < ur->length)
906 		dwc3_ep0_stall_and_restart(dwc);
907 	else
908 		dwc3_gadget_giveback(ep0, r, 0);
909 }
910 
911 static void dwc3_ep0_complete_status(struct dwc3 *dwc,
912 		const struct dwc3_event_depevt *event)
913 {
914 	struct dwc3_request	*r;
915 	struct dwc3_ep		*dep;
916 	struct dwc3_trb		*trb;
917 	u32			status;
918 
919 	dep = dwc->eps[0];
920 	trb = dwc->ep0_trb;
921 
922 	trace_dwc3_complete_trb(dep, trb);
923 
924 	if (!list_empty(&dep->pending_list)) {
925 		r = next_request(&dep->pending_list);
926 
927 		dwc3_gadget_giveback(dep, r, 0);
928 	}
929 
930 	if (dwc->test_mode) {
931 		int ret;
932 
933 		ret = dwc3_gadget_set_test_mode(dwc, dwc->test_mode_nr);
934 		if (ret < 0) {
935 			dev_err(dwc->dev, "invalid test #%d\n",
936 					dwc->test_mode_nr);
937 			dwc3_ep0_stall_and_restart(dwc);
938 			return;
939 		}
940 	}
941 
942 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
943 	if (status == DWC3_TRBSTS_SETUP_PENDING)
944 		dwc->setup_packet_pending = true;
945 
946 	dwc->ep0state = EP0_SETUP_PHASE;
947 	dwc3_ep0_out_start(dwc);
948 }
949 
950 static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
951 			const struct dwc3_event_depevt *event)
952 {
953 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
954 
955 	dep->flags &= ~DWC3_EP_TRANSFER_STARTED;
956 	dep->resource_index = 0;
957 	dwc->setup_packet_pending = false;
958 
959 	switch (dwc->ep0state) {
960 	case EP0_SETUP_PHASE:
961 		dwc3_ep0_inspect_setup(dwc, event);
962 		break;
963 
964 	case EP0_DATA_PHASE:
965 		dwc3_ep0_complete_data(dwc, event);
966 		break;
967 
968 	case EP0_STATUS_PHASE:
969 		dwc3_ep0_complete_status(dwc, event);
970 		break;
971 	default:
972 		WARN(true, "UNKNOWN ep0state %d\n", dwc->ep0state);
973 	}
974 }
975 
976 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
977 		struct dwc3_ep *dep, struct dwc3_request *req)
978 {
979 	unsigned int		trb_length = 0;
980 	int			ret;
981 
982 	req->direction = !!dep->number;
983 
984 	if (req->request.length == 0) {
985 		if (!req->direction)
986 			trb_length = dep->endpoint.maxpacket;
987 
988 		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr, trb_length,
989 				DWC3_TRBCTL_CONTROL_DATA, false);
990 		ret = dwc3_ep0_start_trans(dep);
991 	} else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
992 			&& (dep->number == 0)) {
993 		u32	maxpacket;
994 		u32	rem;
995 
996 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
997 				&req->request, dep->number);
998 		if (ret)
999 			return;
1000 
1001 		maxpacket = dep->endpoint.maxpacket;
1002 		rem = req->request.length % maxpacket;
1003 		dwc->ep0_bounced = true;
1004 
1005 		/* prepare normal TRB */
1006 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
1007 					 req->request.length,
1008 					 DWC3_TRBCTL_CONTROL_DATA,
1009 					 true);
1010 
1011 		req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1];
1012 
1013 		/* Now prepare one extra TRB to align transfer size */
1014 		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr,
1015 					 maxpacket - rem,
1016 					 DWC3_TRBCTL_CONTROL_DATA,
1017 					 false);
1018 		ret = dwc3_ep0_start_trans(dep);
1019 	} else if (IS_ALIGNED(req->request.length, dep->endpoint.maxpacket) &&
1020 		   req->request.length && req->request.zero) {
1021 
1022 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
1023 				&req->request, dep->number);
1024 		if (ret)
1025 			return;
1026 
1027 		/* prepare normal TRB */
1028 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
1029 					 req->request.length,
1030 					 DWC3_TRBCTL_CONTROL_DATA,
1031 					 true);
1032 
1033 		req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1];
1034 
1035 		if (!req->direction)
1036 			trb_length = dep->endpoint.maxpacket;
1037 
1038 		/* Now prepare one extra TRB to align transfer size */
1039 		dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr,
1040 					 trb_length, DWC3_TRBCTL_CONTROL_DATA,
1041 					 false);
1042 		ret = dwc3_ep0_start_trans(dep);
1043 	} else {
1044 		ret = usb_gadget_map_request_by_dev(dwc->sysdev,
1045 				&req->request, dep->number);
1046 		if (ret)
1047 			return;
1048 
1049 		dwc3_ep0_prepare_one_trb(dep, req->request.dma,
1050 				req->request.length, DWC3_TRBCTL_CONTROL_DATA,
1051 				false);
1052 
1053 		req->trb = &dwc->ep0_trb[dep->trb_enqueue];
1054 
1055 		ret = dwc3_ep0_start_trans(dep);
1056 	}
1057 
1058 	WARN_ON(ret < 0);
1059 }
1060 
1061 static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
1062 {
1063 	struct dwc3		*dwc = dep->dwc;
1064 	u32			type;
1065 
1066 	type = dwc->three_stage_setup ? DWC3_TRBCTL_CONTROL_STATUS3
1067 		: DWC3_TRBCTL_CONTROL_STATUS2;
1068 
1069 	dwc3_ep0_prepare_one_trb(dep, dwc->ep0_trb_addr, 0, type, false);
1070 	return dwc3_ep0_start_trans(dep);
1071 }
1072 
1073 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)
1074 {
1075 	WARN_ON(dwc3_ep0_start_control_status(dep));
1076 }
1077 
1078 static void dwc3_ep0_do_control_status(struct dwc3 *dwc,
1079 		const struct dwc3_event_depevt *event)
1080 {
1081 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
1082 
1083 	__dwc3_ep0_do_control_status(dwc, dep);
1084 }
1085 
1086 void dwc3_ep0_send_delayed_status(struct dwc3 *dwc)
1087 {
1088 	unsigned int direction = !dwc->ep0_expect_in;
1089 
1090 	dwc->delayed_status = false;
1091 	dwc->clear_stall_protocol = 0;
1092 
1093 	if (dwc->ep0state != EP0_STATUS_PHASE)
1094 		return;
1095 
1096 	__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
1097 }
1098 
1099 void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep)
1100 {
1101 	struct dwc3_gadget_ep_cmd_params params;
1102 	u32			cmd;
1103 	int			ret;
1104 
1105 	/*
1106 	 * For status/DATA OUT stage, TRB will be queued on ep0 out
1107 	 * endpoint for which resource index is zero. Hence allow
1108 	 * queuing ENDXFER command for ep0 out endpoint.
1109 	 */
1110 	if (!dep->resource_index && dep->number)
1111 		return;
1112 
1113 	cmd = DWC3_DEPCMD_ENDTRANSFER;
1114 	cmd |= DWC3_DEPCMD_CMDIOC;
1115 	cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
1116 	memset(&params, 0, sizeof(params));
1117 	ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
1118 	WARN_ON_ONCE(ret);
1119 	dep->resource_index = 0;
1120 }
1121 
1122 static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
1123 		const struct dwc3_event_depevt *event)
1124 {
1125 	switch (event->status) {
1126 	case DEPEVT_STATUS_CONTROL_DATA:
1127 		if (!dwc->softconnect || !dwc->connected)
1128 			return;
1129 		/*
1130 		 * We already have a DATA transfer in the controller's cache,
1131 		 * if we receive a XferNotReady(DATA) we will ignore it, unless
1132 		 * it's for the wrong direction.
1133 		 *
1134 		 * In that case, we must issue END_TRANSFER command to the Data
1135 		 * Phase we already have started and issue SetStall on the
1136 		 * control endpoint.
1137 		 */
1138 		if (dwc->ep0_expect_in != event->endpoint_number) {
1139 			struct dwc3_ep	*dep = dwc->eps[dwc->ep0_expect_in];
1140 
1141 			dev_err(dwc->dev, "unexpected direction for Data Phase\n");
1142 			dwc3_ep0_end_control_data(dwc, dep);
1143 			dwc3_ep0_stall_and_restart(dwc);
1144 			return;
1145 		}
1146 
1147 		break;
1148 
1149 	case DEPEVT_STATUS_CONTROL_STATUS:
1150 		if (dwc->ep0_next_event != DWC3_EP0_NRDY_STATUS)
1151 			return;
1152 
1153 		if (dwc->setup_packet_pending) {
1154 			dwc3_ep0_stall_and_restart(dwc);
1155 			return;
1156 		}
1157 
1158 		dwc->ep0state = EP0_STATUS_PHASE;
1159 
1160 		if (dwc->delayed_status) {
1161 			struct dwc3_ep *dep = dwc->eps[0];
1162 
1163 			WARN_ON_ONCE(event->endpoint_number != 1);
1164 			/*
1165 			 * We should handle the delay STATUS phase here if the
1166 			 * request for handling delay STATUS has been queued
1167 			 * into the list.
1168 			 */
1169 			if (!list_empty(&dep->pending_list)) {
1170 				dwc->delayed_status = false;
1171 				usb_gadget_set_state(dwc->gadget,
1172 						     USB_STATE_CONFIGURED);
1173 				dwc3_ep0_do_control_status(dwc, event);
1174 			}
1175 
1176 			return;
1177 		}
1178 
1179 		dwc3_ep0_do_control_status(dwc, event);
1180 	}
1181 }
1182 
1183 void dwc3_ep0_interrupt(struct dwc3 *dwc,
1184 		const struct dwc3_event_depevt *event)
1185 {
1186 	struct dwc3_ep	*dep = dwc->eps[event->endpoint_number];
1187 	u8		cmd;
1188 
1189 	switch (event->endpoint_event) {
1190 	case DWC3_DEPEVT_XFERCOMPLETE:
1191 		dwc3_ep0_xfer_complete(dwc, event);
1192 		break;
1193 
1194 	case DWC3_DEPEVT_XFERNOTREADY:
1195 		dwc3_ep0_xfernotready(dwc, event);
1196 		break;
1197 
1198 	case DWC3_DEPEVT_XFERINPROGRESS:
1199 	case DWC3_DEPEVT_RXTXFIFOEVT:
1200 	case DWC3_DEPEVT_STREAMEVT:
1201 		break;
1202 	case DWC3_DEPEVT_EPCMDCMPLT:
1203 		cmd = DEPEVT_PARAMETER_CMD(event->parameters);
1204 
1205 		if (cmd == DWC3_DEPCMD_ENDTRANSFER) {
1206 			dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;
1207 			dep->flags &= ~DWC3_EP_TRANSFER_STARTED;
1208 		}
1209 		break;
1210 	default:
1211 		dev_err(dwc->dev, "unknown endpoint event %d\n", event->endpoint_event);
1212 		break;
1213 	}
1214 }
1215