xref: /rk3399_rockchip-uboot/drivers/usb/dwc3/ep0.c (revision b6d959acaae08fa217f539245893c663d63a8b7a)
1 /**
2  * ep0.c - DesignWare USB3 DRD Controller Endpoint 0 Handling
3  *
4  * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com
5  *
6  * Authors: Felipe Balbi <balbi@ti.com>,
7  *	    Sebastian Andrzej Siewior <bigeasy@linutronix.de>
8  *
9  * Taken from Linux Kernel v3.19-rc1 (drivers/usb/dwc3/ep0.c) and ported
10  * to uboot.
11  *
12  * commit c00552ebaf : Merge 3.18-rc7 into usb-next
13  *
14  * SPDX-License-Identifier:     GPL-2.0
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/list.h>
19 
20 #include <linux/usb/ch9.h>
21 #include <linux/usb/gadget.h>
22 #include <linux/usb/composite.h>
23 
24 #include "core.h"
25 #include "gadget.h"
26 #include "io.h"
27 
28 #include "linux-compat.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 const char *dwc3_ep0_state_string(enum dwc3_ep0_state state)
35 {
36 	switch (state) {
37 	case EP0_UNCONNECTED:
38 		return "Unconnected";
39 	case EP0_SETUP_PHASE:
40 		return "Setup Phase";
41 	case EP0_DATA_PHASE:
42 		return "Data Phase";
43 	case EP0_STATUS_PHASE:
44 		return "Status Phase";
45 	default:
46 		return "UNKNOWN";
47 	}
48 }
49 
50 static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
51 		u32 len, u32 type)
52 {
53 	struct dwc3_gadget_ep_cmd_params params;
54 	struct dwc3_trb			*trb;
55 	struct dwc3_ep			*dep;
56 
57 	int				ret;
58 
59 	dep = dwc->eps[epnum];
60 	if (dep->flags & DWC3_EP_BUSY) {
61 		dev_vdbg(dwc->dev, "%s still busy", dep->name);
62 		return 0;
63 	}
64 
65 	trb = dwc->ep0_trb;
66 
67 	trb->bpl = lower_32_bits(buf_dma);
68 	trb->bph = upper_32_bits(buf_dma);
69 	trb->size = len;
70 	trb->ctrl = type;
71 
72 	trb->ctrl |= (DWC3_TRB_CTRL_HWO
73 			| DWC3_TRB_CTRL_LST
74 			| DWC3_TRB_CTRL_IOC
75 			| DWC3_TRB_CTRL_ISP_IMI);
76 
77 	memset(&params, 0, sizeof(params));
78 	params.param0 = upper_32_bits(dwc->ep0_trb_addr);
79 	params.param1 = lower_32_bits(dwc->ep0_trb_addr);
80 
81 	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
82 			DWC3_DEPCMD_STARTTRANSFER, &params);
83 	if (ret < 0) {
84 		dev_dbg(dwc->dev, "%s STARTTRANSFER failed", dep->name);
85 		return ret;
86 	}
87 
88 	dep->flags |= DWC3_EP_BUSY;
89 	dep->resource_index = dwc3_gadget_ep_get_transfer_index(dwc,
90 			dep->number);
91 
92 	dwc->ep0_next_event = DWC3_EP0_COMPLETE;
93 
94 	return 0;
95 }
96 
97 static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep,
98 		struct dwc3_request *req)
99 {
100 	struct dwc3		*dwc = dep->dwc;
101 
102 	req->request.actual	= 0;
103 	req->request.status	= -EINPROGRESS;
104 	req->epnum		= dep->number;
105 
106 	list_add_tail(&req->list, &dep->request_list);
107 
108 	/*
109 	 * Gadget driver might not be quick enough to queue a request
110 	 * before we get a Transfer Not Ready event on this endpoint.
111 	 *
112 	 * In that case, we will set DWC3_EP_PENDING_REQUEST. When that
113 	 * flag is set, it's telling us that as soon as Gadget queues the
114 	 * required request, we should kick the transfer here because the
115 	 * IRQ we were waiting for is long gone.
116 	 */
117 	if (dep->flags & DWC3_EP_PENDING_REQUEST) {
118 		unsigned	direction;
119 
120 		direction = !!(dep->flags & DWC3_EP0_DIR_IN);
121 
122 		if (dwc->ep0state != EP0_DATA_PHASE) {
123 			dev_WARN(dwc->dev, "Unexpected pending request\n");
124 			return 0;
125 		}
126 
127 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
128 
129 		dep->flags &= ~(DWC3_EP_PENDING_REQUEST |
130 				DWC3_EP0_DIR_IN);
131 
132 		return 0;
133 	}
134 
135 	/*
136 	 * In case gadget driver asked us to delay the STATUS phase,
137 	 * handle it here.
138 	 */
139 	if (dwc->delayed_status) {
140 		unsigned	direction;
141 
142 		direction = !dwc->ep0_expect_in;
143 		dwc->delayed_status = false;
144 		usb_gadget_set_state(&dwc->gadget, USB_STATE_CONFIGURED);
145 
146 		if (dwc->ep0state == EP0_STATUS_PHASE)
147 			__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
148 		else
149 			dev_dbg(dwc->dev, "too early for delayed status");
150 
151 		return 0;
152 	}
153 
154 	/*
155 	 * Unfortunately we have uncovered a limitation wrt the Data Phase.
156 	 *
157 	 * Section 9.4 says we can wait for the XferNotReady(DATA) event to
158 	 * come before issueing Start Transfer command, but if we do, we will
159 	 * miss situations where the host starts another SETUP phase instead of
160 	 * the DATA phase.  Such cases happen at least on TD.7.6 of the Link
161 	 * Layer Compliance Suite.
162 	 *
163 	 * The problem surfaces due to the fact that in case of back-to-back
164 	 * SETUP packets there will be no XferNotReady(DATA) generated and we
165 	 * will be stuck waiting for XferNotReady(DATA) forever.
166 	 *
167 	 * By looking at tables 9-13 and 9-14 of the Databook, we can see that
168 	 * it tells us to start Data Phase right away. It also mentions that if
169 	 * we receive a SETUP phase instead of the DATA phase, core will issue
170 	 * XferComplete for the DATA phase, before actually initiating it in
171 	 * the wire, with the TRB's status set to "SETUP_PENDING". Such status
172 	 * can only be used to print some debugging logs, as the core expects
173 	 * us to go through to the STATUS phase and start a CONTROL_STATUS TRB,
174 	 * just so it completes right away, without transferring anything and,
175 	 * only then, we can go back to the SETUP phase.
176 	 *
177 	 * Because of this scenario, SNPS decided to change the programming
178 	 * model of control transfers and support on-demand transfers only for
179 	 * the STATUS phase. To fix the issue we have now, we will always wait
180 	 * for gadget driver to queue the DATA phase's struct usb_request, then
181 	 * start it right away.
182 	 *
183 	 * If we're actually in a 2-stage transfer, we will wait for
184 	 * XferNotReady(STATUS).
185 	 */
186 	if (dwc->three_stage_setup) {
187 		unsigned        direction;
188 
189 		direction = dwc->ep0_expect_in;
190 		dwc->ep0state = EP0_DATA_PHASE;
191 
192 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
193 
194 		dep->flags &= ~DWC3_EP0_DIR_IN;
195 	}
196 
197 	return 0;
198 }
199 
200 int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
201 		gfp_t gfp_flags)
202 {
203 	struct dwc3_request		*req = to_dwc3_request(request);
204 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
205 	struct dwc3			*dwc = dep->dwc;
206 
207 	unsigned long			flags;
208 
209 	int				ret;
210 
211 	spin_lock_irqsave(&dwc->lock, flags);
212 	if (!dep->endpoint.desc) {
213 		dev_dbg(dwc->dev, "trying to queue request %p to disabled %s",
214 				request, dep->name);
215 		ret = -ESHUTDOWN;
216 		goto out;
217 	}
218 
219 	/* we share one TRB for ep0/1 */
220 	if (!list_empty(&dep->request_list)) {
221 		ret = -EBUSY;
222 		goto out;
223 	}
224 
225 	dev_vdbg(dwc->dev, "queueing request %p to %s length %d state '%s'",
226 			request, dep->name, request->length,
227 			dwc3_ep0_state_string(dwc->ep0state));
228 
229 	ret = __dwc3_gadget_ep0_queue(dep, req);
230 
231 out:
232 	spin_unlock_irqrestore(&dwc->lock, flags);
233 
234 	return ret;
235 }
236 
237 static void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
238 {
239 	struct dwc3_ep		*dep;
240 
241 	/* reinitialize physical ep1 */
242 	dep = dwc->eps[1];
243 	dep->flags = DWC3_EP_ENABLED;
244 
245 	/* stall is always issued on EP0 */
246 	dep = dwc->eps[0];
247 	__dwc3_gadget_ep_set_halt(dep, 1, false);
248 	dep->flags = DWC3_EP_ENABLED;
249 	dwc->delayed_status = false;
250 
251 	if (!list_empty(&dep->request_list)) {
252 		struct dwc3_request	*req;
253 
254 		req = next_request(&dep->request_list);
255 		dwc3_gadget_giveback(dep, req, -ECONNRESET);
256 	}
257 
258 	dwc->ep0state = EP0_SETUP_PHASE;
259 	dwc3_ep0_out_start(dwc);
260 }
261 
262 int __dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
263 {
264 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
265 	struct dwc3			*dwc = dep->dwc;
266 
267 	dwc3_ep0_stall_and_restart(dwc);
268 
269 	return 0;
270 }
271 
272 int dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
273 {
274 	unsigned long			flags;
275 	int				ret;
276 
277 	spin_lock_irqsave(&dwc->lock, flags);
278 	ret = __dwc3_gadget_ep0_set_halt(ep, value);
279 	spin_unlock_irqrestore(&dwc->lock, flags);
280 
281 	return ret;
282 }
283 
284 void dwc3_ep0_out_start(struct dwc3 *dwc)
285 {
286 	int				ret;
287 
288 	ret = dwc3_ep0_start_trans(dwc, 0, dwc->ctrl_req_addr, 8,
289 			DWC3_TRBCTL_CONTROL_SETUP);
290 	WARN_ON(ret < 0);
291 }
292 
293 static struct dwc3_ep *dwc3_wIndex_to_dep(struct dwc3 *dwc, __le16 wIndex_le)
294 {
295 	struct dwc3_ep		*dep;
296 	u32			windex = le16_to_cpu(wIndex_le);
297 	u32			epnum;
298 
299 	epnum = (windex & USB_ENDPOINT_NUMBER_MASK) << 1;
300 	if ((windex & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN)
301 		epnum |= 1;
302 
303 	dep = dwc->eps[epnum];
304 	if (dep->flags & DWC3_EP_ENABLED)
305 		return dep;
306 
307 	return NULL;
308 }
309 
310 static void dwc3_ep0_status_cmpl(struct usb_ep *ep, struct usb_request *req)
311 {
312 }
313 /*
314  * ch 9.4.5
315  */
316 static int dwc3_ep0_handle_status(struct dwc3 *dwc,
317 		struct usb_ctrlrequest *ctrl)
318 {
319 	struct dwc3_ep		*dep;
320 	u32			recip;
321 	u32			reg;
322 	u16			usb_status = 0;
323 	__le16			*response_pkt;
324 
325 	recip = ctrl->bRequestType & USB_RECIP_MASK;
326 	switch (recip) {
327 	case USB_RECIP_DEVICE:
328 		/*
329 		 * LTM will be set once we know how to set this in HW.
330 		 */
331 		usb_status |= dwc->is_selfpowered << USB_DEVICE_SELF_POWERED;
332 
333 		if (dwc->speed == DWC3_DSTS_SUPERSPEED) {
334 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
335 			if (reg & DWC3_DCTL_INITU1ENA)
336 				usb_status |= 1 << USB_DEV_STAT_U1_ENABLED;
337 			if (reg & DWC3_DCTL_INITU2ENA)
338 				usb_status |= 1 << USB_DEV_STAT_U2_ENABLED;
339 		}
340 
341 		break;
342 
343 	case USB_RECIP_INTERFACE:
344 		/*
345 		 * Function Remote Wake Capable	D0
346 		 * Function Remote Wakeup	D1
347 		 */
348 		break;
349 
350 	case USB_RECIP_ENDPOINT:
351 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
352 		if (!dep)
353 			return -EINVAL;
354 
355 		if (dep->flags & DWC3_EP_STALL)
356 			usb_status = 1 << USB_ENDPOINT_HALT;
357 		break;
358 	default:
359 		return -EINVAL;
360 	}
361 
362 	response_pkt = (__le16 *) dwc->setup_buf;
363 	*response_pkt = cpu_to_le16(usb_status);
364 
365 	dep = dwc->eps[0];
366 	dwc->ep0_usb_req.dep = dep;
367 	dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
368 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
369 	dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
370 
371 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
372 }
373 
374 static int dwc3_ep0_handle_feature(struct dwc3 *dwc,
375 		struct usb_ctrlrequest *ctrl, int set)
376 {
377 	struct dwc3_ep		*dep;
378 	u32			recip;
379 	u32			wValue;
380 	u32			wIndex;
381 	u32			reg;
382 	int			ret;
383 	enum usb_device_state	state;
384 
385 	wValue = le16_to_cpu(ctrl->wValue);
386 	wIndex = le16_to_cpu(ctrl->wIndex);
387 	recip = ctrl->bRequestType & USB_RECIP_MASK;
388 	state = dwc->gadget.state;
389 
390 	switch (recip) {
391 	case USB_RECIP_DEVICE:
392 
393 		switch (wValue) {
394 		case USB_DEVICE_REMOTE_WAKEUP:
395 			break;
396 		/*
397 		 * 9.4.1 says only only for SS, in AddressState only for
398 		 * default control pipe
399 		 */
400 		case USB_DEVICE_U1_ENABLE:
401 			if (state != USB_STATE_CONFIGURED)
402 				return -EINVAL;
403 			if (dwc->speed != DWC3_DSTS_SUPERSPEED)
404 				return -EINVAL;
405 
406 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
407 			if (set)
408 				reg |= DWC3_DCTL_INITU1ENA;
409 			else
410 				reg &= ~DWC3_DCTL_INITU1ENA;
411 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
412 			break;
413 
414 		case USB_DEVICE_U2_ENABLE:
415 			if (state != USB_STATE_CONFIGURED)
416 				return -EINVAL;
417 			if (dwc->speed != DWC3_DSTS_SUPERSPEED)
418 				return -EINVAL;
419 
420 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
421 			if (set)
422 				reg |= DWC3_DCTL_INITU2ENA;
423 			else
424 				reg &= ~DWC3_DCTL_INITU2ENA;
425 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
426 			break;
427 
428 		case USB_DEVICE_LTM_ENABLE:
429 			return -EINVAL;
430 
431 		case USB_DEVICE_TEST_MODE:
432 			if ((wIndex & 0xff) != 0)
433 				return -EINVAL;
434 			if (!set)
435 				return -EINVAL;
436 
437 			dwc->test_mode_nr = wIndex >> 8;
438 			dwc->test_mode = true;
439 			break;
440 		default:
441 			return -EINVAL;
442 		}
443 		break;
444 
445 	case USB_RECIP_INTERFACE:
446 		switch (wValue) {
447 		case USB_INTRF_FUNC_SUSPEND:
448 			if (wIndex & USB_INTRF_FUNC_SUSPEND_LP)
449 				/* XXX enable Low power suspend */
450 				;
451 			if (wIndex & USB_INTRF_FUNC_SUSPEND_RW)
452 				/* XXX enable remote wakeup */
453 				;
454 			break;
455 		default:
456 			return -EINVAL;
457 		}
458 		break;
459 
460 	case USB_RECIP_ENDPOINT:
461 		switch (wValue) {
462 		case USB_ENDPOINT_HALT:
463 			dep = dwc3_wIndex_to_dep(dwc, wIndex);
464 			if (!dep)
465 				return -EINVAL;
466 			if (set == 0 && (dep->flags & DWC3_EP_WEDGE))
467 				break;
468 			ret = __dwc3_gadget_ep_set_halt(dep, set, true);
469 			if (ret)
470 				return -EINVAL;
471 			break;
472 		default:
473 			return -EINVAL;
474 		}
475 		break;
476 
477 	default:
478 		return -EINVAL;
479 	}
480 
481 	return 0;
482 }
483 
484 static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
485 {
486 	enum usb_device_state state = dwc->gadget.state;
487 	u32 addr;
488 	u32 reg;
489 
490 	addr = le16_to_cpu(ctrl->wValue);
491 	if (addr > 127) {
492 		dev_dbg(dwc->dev, "invalid device address %d", addr);
493 		return -EINVAL;
494 	}
495 
496 	if (state == USB_STATE_CONFIGURED) {
497 		dev_dbg(dwc->dev, "trying to set address when configured");
498 		return -EINVAL;
499 	}
500 
501 	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
502 	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
503 	reg |= DWC3_DCFG_DEVADDR(addr);
504 	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
505 
506 	if (addr)
507 		usb_gadget_set_state(&dwc->gadget, USB_STATE_ADDRESS);
508 	else
509 		usb_gadget_set_state(&dwc->gadget, USB_STATE_DEFAULT);
510 
511 	return 0;
512 }
513 
514 static int dwc3_ep0_delegate_req(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
515 {
516 	int ret;
517 
518 	spin_unlock(&dwc->lock);
519 	ret = dwc->gadget_driver->setup(&dwc->gadget, ctrl);
520 	spin_lock(&dwc->lock);
521 	return ret;
522 }
523 
524 static int dwc3_ep0_set_config(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
525 {
526 	enum usb_device_state state = dwc->gadget.state;
527 	u32 cfg;
528 	int ret;
529 	u32 reg;
530 
531 	dwc->start_config_issued = false;
532 	cfg = le16_to_cpu(ctrl->wValue);
533 
534 	switch (state) {
535 	case USB_STATE_DEFAULT:
536 		return -EINVAL;
537 
538 	case USB_STATE_ADDRESS:
539 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
540 		/* if the cfg matches and the cfg is non zero */
541 		if (cfg && (!ret || (ret == USB_GADGET_DELAYED_STATUS))) {
542 
543 			/*
544 			 * only change state if set_config has already
545 			 * been processed. If gadget driver returns
546 			 * USB_GADGET_DELAYED_STATUS, we will wait
547 			 * to change the state on the next usb_ep_queue()
548 			 */
549 			if (ret == 0)
550 				usb_gadget_set_state(&dwc->gadget,
551 						USB_STATE_CONFIGURED);
552 
553 			/*
554 			 * Enable transition to U1/U2 state when
555 			 * nothing is pending from application.
556 			 */
557 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
558 			reg |= (DWC3_DCTL_ACCEPTU1ENA | DWC3_DCTL_ACCEPTU2ENA);
559 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
560 
561 			dwc->resize_fifos = true;
562 			dev_dbg(dwc->dev, "resize FIFOs flag SET");
563 		}
564 		break;
565 
566 	case USB_STATE_CONFIGURED:
567 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
568 		if (!cfg && !ret)
569 			usb_gadget_set_state(&dwc->gadget,
570 					USB_STATE_ADDRESS);
571 		break;
572 	default:
573 		ret = -EINVAL;
574 	}
575 	return ret;
576 }
577 
578 static void dwc3_ep0_set_sel_cmpl(struct usb_ep *ep, struct usb_request *req)
579 {
580 	struct dwc3_ep	*dep = to_dwc3_ep(ep);
581 	struct dwc3	*dwc = dep->dwc;
582 
583 	u32		param = 0;
584 	u32		reg;
585 
586 	struct timing {
587 		u8	u1sel;
588 		u8	u1pel;
589 		u16	u2sel;
590 		u16	u2pel;
591 	} __packed timing;
592 
593 	int		ret;
594 
595 	memcpy(&timing, req->buf, sizeof(timing));
596 
597 	dwc->u1sel = timing.u1sel;
598 	dwc->u1pel = timing.u1pel;
599 	dwc->u2sel = le16_to_cpu(timing.u2sel);
600 	dwc->u2pel = le16_to_cpu(timing.u2pel);
601 
602 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
603 	if (reg & DWC3_DCTL_INITU2ENA)
604 		param = dwc->u2pel;
605 	if (reg & DWC3_DCTL_INITU1ENA)
606 		param = dwc->u1pel;
607 
608 	/*
609 	 * According to Synopsys Databook, if parameter is
610 	 * greater than 125, a value of zero should be
611 	 * programmed in the register.
612 	 */
613 	if (param > 125)
614 		param = 0;
615 
616 	/* now that we have the time, issue DGCMD Set Sel */
617 	ret = dwc3_send_gadget_generic_command(dwc,
618 			DWC3_DGCMD_SET_PERIODIC_PAR, param);
619 	WARN_ON(ret < 0);
620 }
621 
622 static int dwc3_ep0_set_sel(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
623 {
624 	struct dwc3_ep	*dep;
625 	enum usb_device_state state = dwc->gadget.state;
626 	u16		wLength;
627 
628 	if (state == USB_STATE_DEFAULT)
629 		return -EINVAL;
630 
631 	wLength = le16_to_cpu(ctrl->wLength);
632 
633 	if (wLength != 6) {
634 		dev_err(dwc->dev, "Set SEL should be 6 bytes, got %d\n",
635 				wLength);
636 		return -EINVAL;
637 	}
638 
639 	/*
640 	 * To handle Set SEL we need to receive 6 bytes from Host. So let's
641 	 * queue a usb_request for 6 bytes.
642 	 *
643 	 * Remember, though, this controller can't handle non-wMaxPacketSize
644 	 * aligned transfers on the OUT direction, so we queue a request for
645 	 * wMaxPacketSize instead.
646 	 */
647 	dep = dwc->eps[0];
648 	dwc->ep0_usb_req.dep = dep;
649 	dwc->ep0_usb_req.request.length = dep->endpoint.maxpacket;
650 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
651 	dwc->ep0_usb_req.request.complete = dwc3_ep0_set_sel_cmpl;
652 
653 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
654 }
655 
656 static int dwc3_ep0_set_isoch_delay(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
657 {
658 	u16		wLength;
659 	u16		wValue;
660 	u16		wIndex;
661 
662 	wValue = le16_to_cpu(ctrl->wValue);
663 	wLength = le16_to_cpu(ctrl->wLength);
664 	wIndex = le16_to_cpu(ctrl->wIndex);
665 
666 	if (wIndex || wLength)
667 		return -EINVAL;
668 
669 	/*
670 	 * REVISIT It's unclear from Databook what to do with this
671 	 * value. For now, just cache it.
672 	 */
673 	dwc->isoch_delay = wValue;
674 
675 	return 0;
676 }
677 
678 static int dwc3_ep0_std_request(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
679 {
680 	int ret;
681 
682 	switch (ctrl->bRequest) {
683 	case USB_REQ_GET_STATUS:
684 		dev_vdbg(dwc->dev, "USB_REQ_GET_STATUS");
685 		ret = dwc3_ep0_handle_status(dwc, ctrl);
686 		break;
687 	case USB_REQ_CLEAR_FEATURE:
688 		dev_vdbg(dwc->dev, "USB_REQ_CLEAR_FEATURE");
689 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 0);
690 		break;
691 	case USB_REQ_SET_FEATURE:
692 		dev_vdbg(dwc->dev, "USB_REQ_SET_FEATURE");
693 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 1);
694 		break;
695 	case USB_REQ_SET_ADDRESS:
696 		dev_vdbg(dwc->dev, "USB_REQ_SET_ADDRESS");
697 		ret = dwc3_ep0_set_address(dwc, ctrl);
698 		break;
699 	case USB_REQ_SET_CONFIGURATION:
700 		dev_vdbg(dwc->dev, "USB_REQ_SET_CONFIGURATION");
701 		ret = dwc3_ep0_set_config(dwc, ctrl);
702 		break;
703 	case USB_REQ_SET_SEL:
704 		dev_vdbg(dwc->dev, "USB_REQ_SET_SEL");
705 		ret = dwc3_ep0_set_sel(dwc, ctrl);
706 		break;
707 	case USB_REQ_SET_ISOCH_DELAY:
708 		dev_vdbg(dwc->dev, "USB_REQ_SET_ISOCH_DELAY");
709 		ret = dwc3_ep0_set_isoch_delay(dwc, ctrl);
710 		break;
711 	default:
712 		dev_vdbg(dwc->dev, "Forwarding to gadget driver");
713 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
714 		break;
715 	}
716 
717 	return ret;
718 }
719 
720 static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
721 		const struct dwc3_event_depevt *event)
722 {
723 	struct usb_ctrlrequest *ctrl = dwc->ctrl_req;
724 	int ret = -EINVAL;
725 	u32 len;
726 
727 	if (!dwc->gadget_driver)
728 		goto out;
729 
730 	len = le16_to_cpu(ctrl->wLength);
731 	if (!len) {
732 		dwc->three_stage_setup = false;
733 		dwc->ep0_expect_in = false;
734 		dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
735 	} else {
736 		dwc->three_stage_setup = true;
737 		dwc->ep0_expect_in = !!(ctrl->bRequestType & USB_DIR_IN);
738 		dwc->ep0_next_event = DWC3_EP0_NRDY_DATA;
739 	}
740 
741 	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
742 		ret = dwc3_ep0_std_request(dwc, ctrl);
743 	else
744 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
745 
746 	if (ret == USB_GADGET_DELAYED_STATUS)
747 		dwc->delayed_status = true;
748 
749 out:
750 	if (ret < 0)
751 		dwc3_ep0_stall_and_restart(dwc);
752 }
753 
754 static void dwc3_ep0_complete_data(struct dwc3 *dwc,
755 		const struct dwc3_event_depevt *event)
756 {
757 	struct dwc3_request	*r = NULL;
758 	struct usb_request	*ur;
759 	struct dwc3_trb		*trb;
760 	struct dwc3_ep		*ep0;
761 	u32			transferred;
762 	u32			status;
763 	u32			length;
764 	u8			epnum;
765 
766 	epnum = event->endpoint_number;
767 	ep0 = dwc->eps[0];
768 
769 	dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
770 
771 	trb = dwc->ep0_trb;
772 
773 	r = next_request(&ep0->request_list);
774 	if (!r)
775 		return;
776 
777 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
778 	if (status == DWC3_TRBSTS_SETUP_PENDING) {
779 		dev_dbg(dwc->dev, "Setup Pending received");
780 
781 		if (r)
782 			dwc3_gadget_giveback(ep0, r, -ECONNRESET);
783 
784 		return;
785 	}
786 
787 	ur = &r->request;
788 
789 	length = trb->size & DWC3_TRB_SIZE_MASK;
790 
791 	if (dwc->ep0_bounced) {
792 		unsigned transfer_size = ur->length;
793 		unsigned maxp = ep0->endpoint.maxpacket;
794 
795 		transfer_size += (maxp - (transfer_size % maxp));
796 		transferred = min_t(u32, ur->length,
797 				transfer_size - length);
798 		memcpy(ur->buf, dwc->ep0_bounce, transferred);
799 	} else {
800 		transferred = ur->length - length;
801 	}
802 
803 	ur->actual += transferred;
804 
805 	if ((epnum & 1) && ur->actual < ur->length) {
806 		/* for some reason we did not get everything out */
807 
808 		dwc3_ep0_stall_and_restart(dwc);
809 	} else {
810 		dwc3_gadget_giveback(ep0, r, 0);
811 
812 		if (IS_ALIGNED(ur->length, ep0->endpoint.maxpacket) &&
813 				ur->length && ur->zero) {
814 			int ret;
815 
816 			dwc->ep0_next_event = DWC3_EP0_COMPLETE;
817 
818 			ret = dwc3_ep0_start_trans(dwc, epnum,
819 					dwc->ctrl_req_addr, 0,
820 					DWC3_TRBCTL_CONTROL_DATA);
821 			WARN_ON(ret < 0);
822 		}
823 	}
824 }
825 
826 static void dwc3_ep0_complete_status(struct dwc3 *dwc,
827 		const struct dwc3_event_depevt *event)
828 {
829 	struct dwc3_request	*r;
830 	struct dwc3_ep		*dep;
831 	struct dwc3_trb		*trb;
832 	u32			status;
833 
834 	dep = dwc->eps[0];
835 	trb = dwc->ep0_trb;
836 
837 	if (!list_empty(&dep->request_list)) {
838 		r = next_request(&dep->request_list);
839 
840 		dwc3_gadget_giveback(dep, r, 0);
841 	}
842 
843 	if (dwc->test_mode) {
844 		int ret;
845 
846 		ret = dwc3_gadget_set_test_mode(dwc, dwc->test_mode_nr);
847 		if (ret < 0) {
848 			dev_dbg(dwc->dev, "Invalid Test #%d",
849 					dwc->test_mode_nr);
850 			dwc3_ep0_stall_and_restart(dwc);
851 			return;
852 		}
853 	}
854 
855 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
856 	if (status == DWC3_TRBSTS_SETUP_PENDING)
857 		dev_dbg(dwc->dev, "Setup Pending received");
858 
859 	dwc->ep0state = EP0_SETUP_PHASE;
860 	dwc3_ep0_out_start(dwc);
861 }
862 
863 static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
864 			const struct dwc3_event_depevt *event)
865 {
866 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
867 
868 	dep->flags &= ~DWC3_EP_BUSY;
869 	dep->resource_index = 0;
870 	dwc->setup_packet_pending = false;
871 
872 	switch (dwc->ep0state) {
873 	case EP0_SETUP_PHASE:
874 		dev_vdbg(dwc->dev, "Setup Phase");
875 		dwc3_ep0_inspect_setup(dwc, event);
876 		break;
877 
878 	case EP0_DATA_PHASE:
879 		dev_vdbg(dwc->dev, "Data Phase");
880 		dwc3_ep0_complete_data(dwc, event);
881 		break;
882 
883 	case EP0_STATUS_PHASE:
884 		dev_vdbg(dwc->dev, "Status Phase");
885 		dwc3_ep0_complete_status(dwc, event);
886 		break;
887 	default:
888 		WARN(true, "UNKNOWN ep0state %d\n", dwc->ep0state);
889 	}
890 }
891 
892 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
893 		struct dwc3_ep *dep, struct dwc3_request *req)
894 {
895 	int			ret;
896 
897 	req->direction = !!dep->number;
898 
899 	if (req->request.length == 0) {
900 		ret = dwc3_ep0_start_trans(dwc, dep->number,
901 				dwc->ctrl_req_addr, 0,
902 				DWC3_TRBCTL_CONTROL_DATA);
903 	} else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
904 			&& (dep->number == 0)) {
905 		u32	transfer_size;
906 		u32	maxpacket;
907 
908 		ret = usb_gadget_map_request(&dwc->gadget, &req->request,
909 				dep->number);
910 		if (ret) {
911 			dev_dbg(dwc->dev, "failed to map request\n");
912 			return;
913 		}
914 
915 		WARN_ON(req->request.length > DWC3_EP0_BOUNCE_SIZE);
916 
917 		maxpacket = dep->endpoint.maxpacket;
918 		transfer_size = roundup(req->request.length, maxpacket);
919 
920 		dwc->ep0_bounced = true;
921 
922 		/*
923 		 * REVISIT in case request length is bigger than
924 		 * DWC3_EP0_BOUNCE_SIZE we will need two chained
925 		 * TRBs to handle the transfer.
926 		 */
927 		ret = dwc3_ep0_start_trans(dwc, dep->number,
928 				dwc->ep0_bounce_addr, transfer_size,
929 				DWC3_TRBCTL_CONTROL_DATA);
930 	} else {
931 		ret = usb_gadget_map_request(&dwc->gadget, &req->request,
932 				dep->number);
933 		if (ret) {
934 			dev_dbg(dwc->dev, "failed to map request\n");
935 			return;
936 		}
937 
938 		ret = dwc3_ep0_start_trans(dwc, dep->number, req->request.dma,
939 				req->request.length, DWC3_TRBCTL_CONTROL_DATA);
940 	}
941 
942 	WARN_ON(ret < 0);
943 }
944 
945 static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
946 {
947 	struct dwc3		*dwc = dep->dwc;
948 	u32			type;
949 
950 	type = dwc->three_stage_setup ? DWC3_TRBCTL_CONTROL_STATUS3
951 		: DWC3_TRBCTL_CONTROL_STATUS2;
952 
953 	return dwc3_ep0_start_trans(dwc, dep->number,
954 			dwc->ctrl_req_addr, 0, type);
955 }
956 
957 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)
958 {
959 	if (dwc->resize_fifos) {
960 		dev_dbg(dwc->dev, "Resizing FIFOs");
961 		dwc3_gadget_resize_tx_fifos(dwc);
962 		dwc->resize_fifos = 0;
963 	}
964 
965 	WARN_ON(dwc3_ep0_start_control_status(dep));
966 }
967 
968 static void dwc3_ep0_do_control_status(struct dwc3 *dwc,
969 		const struct dwc3_event_depevt *event)
970 {
971 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
972 
973 	__dwc3_ep0_do_control_status(dwc, dep);
974 }
975 
976 static void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep)
977 {
978 	struct dwc3_gadget_ep_cmd_params params;
979 	u32			cmd;
980 	int			ret;
981 
982 	if (!dep->resource_index)
983 		return;
984 
985 	cmd = DWC3_DEPCMD_ENDTRANSFER;
986 	cmd |= DWC3_DEPCMD_CMDIOC;
987 	cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
988 	memset(&params, 0, sizeof(params));
989 	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
990 	WARN_ON_ONCE(ret);
991 	dep->resource_index = 0;
992 }
993 
994 static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
995 		const struct dwc3_event_depevt *event)
996 {
997 	dwc->setup_packet_pending = true;
998 
999 	switch (event->status) {
1000 	case DEPEVT_STATUS_CONTROL_DATA:
1001 		dev_vdbg(dwc->dev, "Control Data");
1002 
1003 		/*
1004 		 * We already have a DATA transfer in the controller's cache,
1005 		 * if we receive a XferNotReady(DATA) we will ignore it, unless
1006 		 * it's for the wrong direction.
1007 		 *
1008 		 * In that case, we must issue END_TRANSFER command to the Data
1009 		 * Phase we already have started and issue SetStall on the
1010 		 * control endpoint.
1011 		 */
1012 		if (dwc->ep0_expect_in != event->endpoint_number) {
1013 			struct dwc3_ep	*dep = dwc->eps[dwc->ep0_expect_in];
1014 
1015 			dev_vdbg(dwc->dev, "Wrong direction for Data phase");
1016 			dwc3_ep0_end_control_data(dwc, dep);
1017 			dwc3_ep0_stall_and_restart(dwc);
1018 			return;
1019 		}
1020 
1021 		break;
1022 
1023 	case DEPEVT_STATUS_CONTROL_STATUS:
1024 		if (dwc->ep0_next_event != DWC3_EP0_NRDY_STATUS)
1025 			return;
1026 
1027 		dev_vdbg(dwc->dev, "Control Status");
1028 
1029 		dwc->ep0state = EP0_STATUS_PHASE;
1030 
1031 		if (dwc->delayed_status) {
1032 			WARN_ON_ONCE(event->endpoint_number != 1);
1033 			dev_vdbg(dwc->dev, "Delayed Status");
1034 			return;
1035 		}
1036 
1037 		dwc3_ep0_do_control_status(dwc, event);
1038 	}
1039 }
1040 
1041 void dwc3_ep0_interrupt(struct dwc3 *dwc,
1042 		const struct dwc3_event_depevt *event)
1043 {
1044 	u8			epnum = event->endpoint_number;
1045 
1046 	dev_dbg(dwc->dev, "%s while ep%d%s in state '%s'",
1047 			dwc3_ep_event_string(event->endpoint_event),
1048 			epnum >> 1, (epnum & 1) ? "in" : "out",
1049 			dwc3_ep0_state_string(dwc->ep0state));
1050 
1051 	switch (event->endpoint_event) {
1052 	case DWC3_DEPEVT_XFERCOMPLETE:
1053 		dwc3_ep0_xfer_complete(dwc, event);
1054 		break;
1055 
1056 	case DWC3_DEPEVT_XFERNOTREADY:
1057 		dwc3_ep0_xfernotready(dwc, event);
1058 		break;
1059 
1060 	case DWC3_DEPEVT_XFERINPROGRESS:
1061 	case DWC3_DEPEVT_RXTXFIFOEVT:
1062 	case DWC3_DEPEVT_STREAMEVT:
1063 	case DWC3_DEPEVT_EPCMDCMPLT:
1064 		break;
1065 	}
1066 }
1067