xref: /rk3399_rockchip-uboot/drivers/usb/dwc3/ep0.c (revision 1f78f8fedab10f7b30559d6db9b142be5b6daf75)
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 	dwc3_flush_cache((int)buf_dma, len);
78 	dwc3_flush_cache((int)trb, sizeof(*trb));
79 
80 	memset(&params, 0, sizeof(params));
81 	params.param0 = upper_32_bits(dwc->ep0_trb_addr);
82 	params.param1 = lower_32_bits(dwc->ep0_trb_addr);
83 
84 	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
85 			DWC3_DEPCMD_STARTTRANSFER, &params);
86 	if (ret < 0) {
87 		dev_dbg(dwc->dev, "%s STARTTRANSFER failed", dep->name);
88 		return ret;
89 	}
90 
91 	dep->flags |= DWC3_EP_BUSY;
92 	dep->resource_index = dwc3_gadget_ep_get_transfer_index(dwc,
93 			dep->number);
94 
95 	dwc->ep0_next_event = DWC3_EP0_COMPLETE;
96 
97 	return 0;
98 }
99 
100 static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep,
101 		struct dwc3_request *req)
102 {
103 	struct dwc3		*dwc = dep->dwc;
104 
105 	req->request.actual	= 0;
106 	req->request.status	= -EINPROGRESS;
107 	req->epnum		= dep->number;
108 
109 	list_add_tail(&req->list, &dep->request_list);
110 
111 	/*
112 	 * Gadget driver might not be quick enough to queue a request
113 	 * before we get a Transfer Not Ready event on this endpoint.
114 	 *
115 	 * In that case, we will set DWC3_EP_PENDING_REQUEST. When that
116 	 * flag is set, it's telling us that as soon as Gadget queues the
117 	 * required request, we should kick the transfer here because the
118 	 * IRQ we were waiting for is long gone.
119 	 */
120 	if (dep->flags & DWC3_EP_PENDING_REQUEST) {
121 		unsigned	direction;
122 
123 		direction = !!(dep->flags & DWC3_EP0_DIR_IN);
124 
125 		if (dwc->ep0state != EP0_DATA_PHASE) {
126 			dev_WARN(dwc->dev, "Unexpected pending request\n");
127 			return 0;
128 		}
129 
130 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
131 
132 		dep->flags &= ~(DWC3_EP_PENDING_REQUEST |
133 				DWC3_EP0_DIR_IN);
134 
135 		return 0;
136 	}
137 
138 	/*
139 	 * In case gadget driver asked us to delay the STATUS phase,
140 	 * handle it here.
141 	 */
142 	if (dwc->delayed_status) {
143 		unsigned	direction;
144 
145 		direction = !dwc->ep0_expect_in;
146 		dwc->delayed_status = false;
147 		usb_gadget_set_state(&dwc->gadget, USB_STATE_CONFIGURED);
148 
149 		if (dwc->ep0state == EP0_STATUS_PHASE)
150 			__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
151 		else
152 			dev_dbg(dwc->dev, "too early for delayed status");
153 
154 		return 0;
155 	}
156 
157 	/*
158 	 * Unfortunately we have uncovered a limitation wrt the Data Phase.
159 	 *
160 	 * Section 9.4 says we can wait for the XferNotReady(DATA) event to
161 	 * come before issueing Start Transfer command, but if we do, we will
162 	 * miss situations where the host starts another SETUP phase instead of
163 	 * the DATA phase.  Such cases happen at least on TD.7.6 of the Link
164 	 * Layer Compliance Suite.
165 	 *
166 	 * The problem surfaces due to the fact that in case of back-to-back
167 	 * SETUP packets there will be no XferNotReady(DATA) generated and we
168 	 * will be stuck waiting for XferNotReady(DATA) forever.
169 	 *
170 	 * By looking at tables 9-13 and 9-14 of the Databook, we can see that
171 	 * it tells us to start Data Phase right away. It also mentions that if
172 	 * we receive a SETUP phase instead of the DATA phase, core will issue
173 	 * XferComplete for the DATA phase, before actually initiating it in
174 	 * the wire, with the TRB's status set to "SETUP_PENDING". Such status
175 	 * can only be used to print some debugging logs, as the core expects
176 	 * us to go through to the STATUS phase and start a CONTROL_STATUS TRB,
177 	 * just so it completes right away, without transferring anything and,
178 	 * only then, we can go back to the SETUP phase.
179 	 *
180 	 * Because of this scenario, SNPS decided to change the programming
181 	 * model of control transfers and support on-demand transfers only for
182 	 * the STATUS phase. To fix the issue we have now, we will always wait
183 	 * for gadget driver to queue the DATA phase's struct usb_request, then
184 	 * start it right away.
185 	 *
186 	 * If we're actually in a 2-stage transfer, we will wait for
187 	 * XferNotReady(STATUS).
188 	 */
189 	if (dwc->three_stage_setup) {
190 		unsigned        direction;
191 
192 		direction = dwc->ep0_expect_in;
193 		dwc->ep0state = EP0_DATA_PHASE;
194 
195 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
196 
197 		dep->flags &= ~DWC3_EP0_DIR_IN;
198 	}
199 
200 	return 0;
201 }
202 
203 int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
204 		gfp_t gfp_flags)
205 {
206 	struct dwc3_request		*req = to_dwc3_request(request);
207 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
208 	struct dwc3			*dwc = dep->dwc;
209 
210 	unsigned long			flags;
211 
212 	int				ret;
213 
214 	spin_lock_irqsave(&dwc->lock, flags);
215 	if (!dep->endpoint.desc) {
216 		dev_dbg(dwc->dev, "trying to queue request %p to disabled %s",
217 				request, dep->name);
218 		ret = -ESHUTDOWN;
219 		goto out;
220 	}
221 
222 	/* we share one TRB for ep0/1 */
223 	if (!list_empty(&dep->request_list)) {
224 		ret = -EBUSY;
225 		goto out;
226 	}
227 
228 	dev_vdbg(dwc->dev, "queueing request %p to %s length %d state '%s'",
229 			request, dep->name, request->length,
230 			dwc3_ep0_state_string(dwc->ep0state));
231 
232 	ret = __dwc3_gadget_ep0_queue(dep, req);
233 
234 out:
235 	spin_unlock_irqrestore(&dwc->lock, flags);
236 
237 	return ret;
238 }
239 
240 static void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
241 {
242 	struct dwc3_ep		*dep;
243 
244 	/* reinitialize physical ep1 */
245 	dep = dwc->eps[1];
246 	dep->flags = DWC3_EP_ENABLED;
247 
248 	/* stall is always issued on EP0 */
249 	dep = dwc->eps[0];
250 	__dwc3_gadget_ep_set_halt(dep, 1, false);
251 	dep->flags = DWC3_EP_ENABLED;
252 	dwc->delayed_status = false;
253 
254 	if (!list_empty(&dep->request_list)) {
255 		struct dwc3_request	*req;
256 
257 		req = next_request(&dep->request_list);
258 		dwc3_gadget_giveback(dep, req, -ECONNRESET);
259 	}
260 
261 	dwc->ep0state = EP0_SETUP_PHASE;
262 	dwc3_ep0_out_start(dwc);
263 }
264 
265 int __dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
266 {
267 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
268 	struct dwc3			*dwc = dep->dwc;
269 
270 	dwc3_ep0_stall_and_restart(dwc);
271 
272 	return 0;
273 }
274 
275 int dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
276 {
277 	unsigned long			flags;
278 	int				ret;
279 
280 	spin_lock_irqsave(&dwc->lock, flags);
281 	ret = __dwc3_gadget_ep0_set_halt(ep, value);
282 	spin_unlock_irqrestore(&dwc->lock, flags);
283 
284 	return ret;
285 }
286 
287 void dwc3_ep0_out_start(struct dwc3 *dwc)
288 {
289 	int				ret;
290 
291 	ret = dwc3_ep0_start_trans(dwc, 0, dwc->ctrl_req_addr, 8,
292 			DWC3_TRBCTL_CONTROL_SETUP);
293 	WARN_ON(ret < 0);
294 }
295 
296 static struct dwc3_ep *dwc3_wIndex_to_dep(struct dwc3 *dwc, __le16 wIndex_le)
297 {
298 	struct dwc3_ep		*dep;
299 	u32			windex = le16_to_cpu(wIndex_le);
300 	u32			epnum;
301 
302 	epnum = (windex & USB_ENDPOINT_NUMBER_MASK) << 1;
303 	if ((windex & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN)
304 		epnum |= 1;
305 
306 	dep = dwc->eps[epnum];
307 	if (dep->flags & DWC3_EP_ENABLED)
308 		return dep;
309 
310 	return NULL;
311 }
312 
313 static void dwc3_ep0_status_cmpl(struct usb_ep *ep, struct usb_request *req)
314 {
315 }
316 /*
317  * ch 9.4.5
318  */
319 static int dwc3_ep0_handle_status(struct dwc3 *dwc,
320 		struct usb_ctrlrequest *ctrl)
321 {
322 	struct dwc3_ep		*dep;
323 	u32			recip;
324 	u32			reg;
325 	u16			usb_status = 0;
326 	__le16			*response_pkt;
327 
328 	recip = ctrl->bRequestType & USB_RECIP_MASK;
329 	switch (recip) {
330 	case USB_RECIP_DEVICE:
331 		/*
332 		 * LTM will be set once we know how to set this in HW.
333 		 */
334 		usb_status |= dwc->is_selfpowered << USB_DEVICE_SELF_POWERED;
335 
336 		if (dwc->speed == DWC3_DSTS_SUPERSPEED) {
337 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
338 			if (reg & DWC3_DCTL_INITU1ENA)
339 				usb_status |= 1 << USB_DEV_STAT_U1_ENABLED;
340 			if (reg & DWC3_DCTL_INITU2ENA)
341 				usb_status |= 1 << USB_DEV_STAT_U2_ENABLED;
342 		}
343 
344 		break;
345 
346 	case USB_RECIP_INTERFACE:
347 		/*
348 		 * Function Remote Wake Capable	D0
349 		 * Function Remote Wakeup	D1
350 		 */
351 		break;
352 
353 	case USB_RECIP_ENDPOINT:
354 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
355 		if (!dep)
356 			return -EINVAL;
357 
358 		if (dep->flags & DWC3_EP_STALL)
359 			usb_status = 1 << USB_ENDPOINT_HALT;
360 		break;
361 	default:
362 		return -EINVAL;
363 	}
364 
365 	response_pkt = (__le16 *) dwc->setup_buf;
366 	*response_pkt = cpu_to_le16(usb_status);
367 
368 	dep = dwc->eps[0];
369 	dwc->ep0_usb_req.dep = dep;
370 	dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
371 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
372 	dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
373 
374 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
375 }
376 
377 static int dwc3_ep0_handle_feature(struct dwc3 *dwc,
378 		struct usb_ctrlrequest *ctrl, int set)
379 {
380 	struct dwc3_ep		*dep;
381 	u32			recip;
382 	u32			wValue;
383 	u32			wIndex;
384 	u32			reg;
385 	int			ret;
386 	enum usb_device_state	state;
387 
388 	wValue = le16_to_cpu(ctrl->wValue);
389 	wIndex = le16_to_cpu(ctrl->wIndex);
390 	recip = ctrl->bRequestType & USB_RECIP_MASK;
391 	state = dwc->gadget.state;
392 
393 	switch (recip) {
394 	case USB_RECIP_DEVICE:
395 
396 		switch (wValue) {
397 		case USB_DEVICE_REMOTE_WAKEUP:
398 			break;
399 		/*
400 		 * 9.4.1 says only only for SS, in AddressState only for
401 		 * default control pipe
402 		 */
403 		case USB_DEVICE_U1_ENABLE:
404 			if (state != USB_STATE_CONFIGURED)
405 				return -EINVAL;
406 			if (dwc->speed != DWC3_DSTS_SUPERSPEED)
407 				return -EINVAL;
408 
409 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
410 			if (set)
411 				reg |= DWC3_DCTL_INITU1ENA;
412 			else
413 				reg &= ~DWC3_DCTL_INITU1ENA;
414 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
415 			break;
416 
417 		case USB_DEVICE_U2_ENABLE:
418 			if (state != USB_STATE_CONFIGURED)
419 				return -EINVAL;
420 			if (dwc->speed != DWC3_DSTS_SUPERSPEED)
421 				return -EINVAL;
422 
423 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
424 			if (set)
425 				reg |= DWC3_DCTL_INITU2ENA;
426 			else
427 				reg &= ~DWC3_DCTL_INITU2ENA;
428 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
429 			break;
430 
431 		case USB_DEVICE_LTM_ENABLE:
432 			return -EINVAL;
433 
434 		case USB_DEVICE_TEST_MODE:
435 			if ((wIndex & 0xff) != 0)
436 				return -EINVAL;
437 			if (!set)
438 				return -EINVAL;
439 
440 			dwc->test_mode_nr = wIndex >> 8;
441 			dwc->test_mode = true;
442 			break;
443 		default:
444 			return -EINVAL;
445 		}
446 		break;
447 
448 	case USB_RECIP_INTERFACE:
449 		switch (wValue) {
450 		case USB_INTRF_FUNC_SUSPEND:
451 			if (wIndex & USB_INTRF_FUNC_SUSPEND_LP)
452 				/* XXX enable Low power suspend */
453 				;
454 			if (wIndex & USB_INTRF_FUNC_SUSPEND_RW)
455 				/* XXX enable remote wakeup */
456 				;
457 			break;
458 		default:
459 			return -EINVAL;
460 		}
461 		break;
462 
463 	case USB_RECIP_ENDPOINT:
464 		switch (wValue) {
465 		case USB_ENDPOINT_HALT:
466 			dep = dwc3_wIndex_to_dep(dwc, wIndex);
467 			if (!dep)
468 				return -EINVAL;
469 			if (set == 0 && (dep->flags & DWC3_EP_WEDGE))
470 				break;
471 			ret = __dwc3_gadget_ep_set_halt(dep, set, true);
472 			if (ret)
473 				return -EINVAL;
474 			break;
475 		default:
476 			return -EINVAL;
477 		}
478 		break;
479 
480 	default:
481 		return -EINVAL;
482 	}
483 
484 	return 0;
485 }
486 
487 static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
488 {
489 	enum usb_device_state state = dwc->gadget.state;
490 	u32 addr;
491 	u32 reg;
492 
493 	addr = le16_to_cpu(ctrl->wValue);
494 	if (addr > 127) {
495 		dev_dbg(dwc->dev, "invalid device address %d", addr);
496 		return -EINVAL;
497 	}
498 
499 	if (state == USB_STATE_CONFIGURED) {
500 		dev_dbg(dwc->dev, "trying to set address when configured");
501 		return -EINVAL;
502 	}
503 
504 	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
505 	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
506 	reg |= DWC3_DCFG_DEVADDR(addr);
507 	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
508 
509 	if (addr)
510 		usb_gadget_set_state(&dwc->gadget, USB_STATE_ADDRESS);
511 	else
512 		usb_gadget_set_state(&dwc->gadget, USB_STATE_DEFAULT);
513 
514 	return 0;
515 }
516 
517 static int dwc3_ep0_delegate_req(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
518 {
519 	int ret;
520 
521 	spin_unlock(&dwc->lock);
522 	ret = dwc->gadget_driver->setup(&dwc->gadget, ctrl);
523 	spin_lock(&dwc->lock);
524 	return ret;
525 }
526 
527 static int dwc3_ep0_set_config(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
528 {
529 	enum usb_device_state state = dwc->gadget.state;
530 	u32 cfg;
531 	int ret;
532 	u32 reg;
533 
534 	dwc->start_config_issued = false;
535 	cfg = le16_to_cpu(ctrl->wValue);
536 
537 	switch (state) {
538 	case USB_STATE_DEFAULT:
539 		return -EINVAL;
540 
541 	case USB_STATE_ADDRESS:
542 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
543 		/* if the cfg matches and the cfg is non zero */
544 		if (cfg && (!ret || (ret == USB_GADGET_DELAYED_STATUS))) {
545 
546 			/*
547 			 * only change state if set_config has already
548 			 * been processed. If gadget driver returns
549 			 * USB_GADGET_DELAYED_STATUS, we will wait
550 			 * to change the state on the next usb_ep_queue()
551 			 */
552 			if (ret == 0)
553 				usb_gadget_set_state(&dwc->gadget,
554 						USB_STATE_CONFIGURED);
555 
556 			/*
557 			 * Enable transition to U1/U2 state when
558 			 * nothing is pending from application.
559 			 */
560 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
561 			reg |= (DWC3_DCTL_ACCEPTU1ENA | DWC3_DCTL_ACCEPTU2ENA);
562 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
563 
564 			dwc->resize_fifos = true;
565 			dev_dbg(dwc->dev, "resize FIFOs flag SET");
566 		}
567 		break;
568 
569 	case USB_STATE_CONFIGURED:
570 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
571 		if (!cfg && !ret)
572 			usb_gadget_set_state(&dwc->gadget,
573 					USB_STATE_ADDRESS);
574 		break;
575 	default:
576 		ret = -EINVAL;
577 	}
578 	return ret;
579 }
580 
581 static void dwc3_ep0_set_sel_cmpl(struct usb_ep *ep, struct usb_request *req)
582 {
583 	struct dwc3_ep	*dep = to_dwc3_ep(ep);
584 	struct dwc3	*dwc = dep->dwc;
585 
586 	u32		param = 0;
587 	u32		reg;
588 
589 	struct timing {
590 		u8	u1sel;
591 		u8	u1pel;
592 		u16	u2sel;
593 		u16	u2pel;
594 	} __packed timing;
595 
596 	int		ret;
597 
598 	memcpy(&timing, req->buf, sizeof(timing));
599 
600 	dwc->u1sel = timing.u1sel;
601 	dwc->u1pel = timing.u1pel;
602 	dwc->u2sel = le16_to_cpu(timing.u2sel);
603 	dwc->u2pel = le16_to_cpu(timing.u2pel);
604 
605 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
606 	if (reg & DWC3_DCTL_INITU2ENA)
607 		param = dwc->u2pel;
608 	if (reg & DWC3_DCTL_INITU1ENA)
609 		param = dwc->u1pel;
610 
611 	/*
612 	 * According to Synopsys Databook, if parameter is
613 	 * greater than 125, a value of zero should be
614 	 * programmed in the register.
615 	 */
616 	if (param > 125)
617 		param = 0;
618 
619 	/* now that we have the time, issue DGCMD Set Sel */
620 	ret = dwc3_send_gadget_generic_command(dwc,
621 			DWC3_DGCMD_SET_PERIODIC_PAR, param);
622 	WARN_ON(ret < 0);
623 }
624 
625 static int dwc3_ep0_set_sel(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
626 {
627 	struct dwc3_ep	*dep;
628 	enum usb_device_state state = dwc->gadget.state;
629 	u16		wLength;
630 
631 	if (state == USB_STATE_DEFAULT)
632 		return -EINVAL;
633 
634 	wLength = le16_to_cpu(ctrl->wLength);
635 
636 	if (wLength != 6) {
637 		dev_err(dwc->dev, "Set SEL should be 6 bytes, got %d\n",
638 				wLength);
639 		return -EINVAL;
640 	}
641 
642 	/*
643 	 * To handle Set SEL we need to receive 6 bytes from Host. So let's
644 	 * queue a usb_request for 6 bytes.
645 	 *
646 	 * Remember, though, this controller can't handle non-wMaxPacketSize
647 	 * aligned transfers on the OUT direction, so we queue a request for
648 	 * wMaxPacketSize instead.
649 	 */
650 	dep = dwc->eps[0];
651 	dwc->ep0_usb_req.dep = dep;
652 	dwc->ep0_usb_req.request.length = dep->endpoint.maxpacket;
653 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
654 	dwc->ep0_usb_req.request.complete = dwc3_ep0_set_sel_cmpl;
655 
656 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
657 }
658 
659 static int dwc3_ep0_set_isoch_delay(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
660 {
661 	u16		wLength;
662 	u16		wValue;
663 	u16		wIndex;
664 
665 	wValue = le16_to_cpu(ctrl->wValue);
666 	wLength = le16_to_cpu(ctrl->wLength);
667 	wIndex = le16_to_cpu(ctrl->wIndex);
668 
669 	if (wIndex || wLength)
670 		return -EINVAL;
671 
672 	/*
673 	 * REVISIT It's unclear from Databook what to do with this
674 	 * value. For now, just cache it.
675 	 */
676 	dwc->isoch_delay = wValue;
677 
678 	return 0;
679 }
680 
681 static int dwc3_ep0_std_request(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
682 {
683 	int ret;
684 
685 	switch (ctrl->bRequest) {
686 	case USB_REQ_GET_STATUS:
687 		dev_vdbg(dwc->dev, "USB_REQ_GET_STATUS");
688 		ret = dwc3_ep0_handle_status(dwc, ctrl);
689 		break;
690 	case USB_REQ_CLEAR_FEATURE:
691 		dev_vdbg(dwc->dev, "USB_REQ_CLEAR_FEATURE");
692 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 0);
693 		break;
694 	case USB_REQ_SET_FEATURE:
695 		dev_vdbg(dwc->dev, "USB_REQ_SET_FEATURE");
696 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 1);
697 		break;
698 	case USB_REQ_SET_ADDRESS:
699 		dev_vdbg(dwc->dev, "USB_REQ_SET_ADDRESS");
700 		ret = dwc3_ep0_set_address(dwc, ctrl);
701 		break;
702 	case USB_REQ_SET_CONFIGURATION:
703 		dev_vdbg(dwc->dev, "USB_REQ_SET_CONFIGURATION");
704 		ret = dwc3_ep0_set_config(dwc, ctrl);
705 		break;
706 	case USB_REQ_SET_SEL:
707 		dev_vdbg(dwc->dev, "USB_REQ_SET_SEL");
708 		ret = dwc3_ep0_set_sel(dwc, ctrl);
709 		break;
710 	case USB_REQ_SET_ISOCH_DELAY:
711 		dev_vdbg(dwc->dev, "USB_REQ_SET_ISOCH_DELAY");
712 		ret = dwc3_ep0_set_isoch_delay(dwc, ctrl);
713 		break;
714 	default:
715 		dev_vdbg(dwc->dev, "Forwarding to gadget driver");
716 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
717 		break;
718 	}
719 
720 	return ret;
721 }
722 
723 static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
724 		const struct dwc3_event_depevt *event)
725 {
726 	struct usb_ctrlrequest *ctrl = dwc->ctrl_req;
727 	int ret = -EINVAL;
728 	u32 len;
729 
730 	if (!dwc->gadget_driver)
731 		goto out;
732 
733 	len = le16_to_cpu(ctrl->wLength);
734 	if (!len) {
735 		dwc->three_stage_setup = false;
736 		dwc->ep0_expect_in = false;
737 		dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
738 	} else {
739 		dwc->three_stage_setup = true;
740 		dwc->ep0_expect_in = !!(ctrl->bRequestType & USB_DIR_IN);
741 		dwc->ep0_next_event = DWC3_EP0_NRDY_DATA;
742 	}
743 
744 	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
745 		ret = dwc3_ep0_std_request(dwc, ctrl);
746 	else
747 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
748 
749 	if (ret == USB_GADGET_DELAYED_STATUS)
750 		dwc->delayed_status = true;
751 
752 out:
753 	if (ret < 0)
754 		dwc3_ep0_stall_and_restart(dwc);
755 }
756 
757 static void dwc3_ep0_complete_data(struct dwc3 *dwc,
758 		const struct dwc3_event_depevt *event)
759 {
760 	struct dwc3_request	*r = NULL;
761 	struct usb_request	*ur;
762 	struct dwc3_trb		*trb;
763 	struct dwc3_ep		*ep0;
764 	unsigned		transfer_size = 0;
765 	unsigned		maxp;
766 	void			*buf;
767 	u32			transferred = 0;
768 	u32			status;
769 	u32			length;
770 	u8			epnum;
771 
772 	epnum = event->endpoint_number;
773 	ep0 = dwc->eps[0];
774 
775 	dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
776 
777 	trb = dwc->ep0_trb;
778 
779 	r = next_request(&ep0->request_list);
780 	if (!r)
781 		return;
782 
783 	dwc3_flush_cache((int)trb, sizeof(*trb));
784 
785 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
786 	if (status == DWC3_TRBSTS_SETUP_PENDING) {
787 		dev_dbg(dwc->dev, "Setup Pending received");
788 
789 		if (r)
790 			dwc3_gadget_giveback(ep0, r, -ECONNRESET);
791 
792 		return;
793 	}
794 
795 	ur = &r->request;
796 	buf = ur->buf;
797 
798 	length = trb->size & DWC3_TRB_SIZE_MASK;
799 
800 	maxp = ep0->endpoint.maxpacket;
801 
802 	if (dwc->ep0_bounced) {
803 		transfer_size = roundup((ur->length - transfer_size),
804 					maxp);
805 		transferred = min_t(u32, ur->length - transferred,
806 				    transfer_size - length);
807 		dwc3_flush_cache((int)dwc->ep0_bounce, DWC3_EP0_BOUNCE_SIZE);
808 		memcpy(buf, dwc->ep0_bounce, transferred);
809 	} else {
810 		transferred = ur->length - length;
811 	}
812 
813 	ur->actual += transferred;
814 
815 	if ((epnum & 1) && ur->actual < ur->length) {
816 		/* for some reason we did not get everything out */
817 
818 		dwc3_ep0_stall_and_restart(dwc);
819 	} else {
820 		dwc3_gadget_giveback(ep0, r, 0);
821 
822 		if (IS_ALIGNED(ur->length, ep0->endpoint.maxpacket) &&
823 				ur->length && ur->zero) {
824 			int ret;
825 
826 			dwc->ep0_next_event = DWC3_EP0_COMPLETE;
827 
828 			ret = dwc3_ep0_start_trans(dwc, epnum,
829 					dwc->ctrl_req_addr, 0,
830 					DWC3_TRBCTL_CONTROL_DATA);
831 			WARN_ON(ret < 0);
832 		}
833 	}
834 }
835 
836 static void dwc3_ep0_complete_status(struct dwc3 *dwc,
837 		const struct dwc3_event_depevt *event)
838 {
839 	struct dwc3_request	*r;
840 	struct dwc3_ep		*dep;
841 	struct dwc3_trb		*trb;
842 	u32			status;
843 
844 	dep = dwc->eps[0];
845 	trb = dwc->ep0_trb;
846 
847 	if (!list_empty(&dep->request_list)) {
848 		r = next_request(&dep->request_list);
849 
850 		dwc3_gadget_giveback(dep, r, 0);
851 	}
852 
853 	if (dwc->test_mode) {
854 		int ret;
855 
856 		ret = dwc3_gadget_set_test_mode(dwc, dwc->test_mode_nr);
857 		if (ret < 0) {
858 			dev_dbg(dwc->dev, "Invalid Test #%d",
859 					dwc->test_mode_nr);
860 			dwc3_ep0_stall_and_restart(dwc);
861 			return;
862 		}
863 	}
864 
865 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
866 	if (status == DWC3_TRBSTS_SETUP_PENDING)
867 		dev_dbg(dwc->dev, "Setup Pending received");
868 
869 	dwc->ep0state = EP0_SETUP_PHASE;
870 	dwc3_ep0_out_start(dwc);
871 }
872 
873 static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
874 			const struct dwc3_event_depevt *event)
875 {
876 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
877 
878 	dep->flags &= ~DWC3_EP_BUSY;
879 	dep->resource_index = 0;
880 	dwc->setup_packet_pending = false;
881 
882 	switch (dwc->ep0state) {
883 	case EP0_SETUP_PHASE:
884 		dev_vdbg(dwc->dev, "Setup Phase");
885 		dwc3_ep0_inspect_setup(dwc, event);
886 		break;
887 
888 	case EP0_DATA_PHASE:
889 		dev_vdbg(dwc->dev, "Data Phase");
890 		dwc3_ep0_complete_data(dwc, event);
891 		break;
892 
893 	case EP0_STATUS_PHASE:
894 		dev_vdbg(dwc->dev, "Status Phase");
895 		dwc3_ep0_complete_status(dwc, event);
896 		break;
897 	default:
898 		WARN(true, "UNKNOWN ep0state %d\n", dwc->ep0state);
899 	}
900 }
901 
902 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
903 		struct dwc3_ep *dep, struct dwc3_request *req)
904 {
905 	int			ret;
906 
907 	req->direction = !!dep->number;
908 
909 	if (req->request.length == 0) {
910 		ret = dwc3_ep0_start_trans(dwc, dep->number,
911 				dwc->ctrl_req_addr, 0,
912 				DWC3_TRBCTL_CONTROL_DATA);
913 	} else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
914 			&& (dep->number == 0)) {
915 		u32	transfer_size;
916 		u32	maxpacket;
917 
918 		ret = usb_gadget_map_request(&dwc->gadget, &req->request,
919 				dep->number);
920 		if (ret) {
921 			dev_dbg(dwc->dev, "failed to map request\n");
922 			return;
923 		}
924 
925 		WARN_ON(req->request.length > DWC3_EP0_BOUNCE_SIZE);
926 
927 		maxpacket = dep->endpoint.maxpacket;
928 		transfer_size = roundup(req->request.length, maxpacket);
929 
930 		dwc->ep0_bounced = true;
931 
932 		/*
933 		 * REVISIT in case request length is bigger than
934 		 * DWC3_EP0_BOUNCE_SIZE we will need two chained
935 		 * TRBs to handle the transfer.
936 		 */
937 		ret = dwc3_ep0_start_trans(dwc, dep->number,
938 				dwc->ep0_bounce_addr, transfer_size,
939 				DWC3_TRBCTL_CONTROL_DATA);
940 	} else {
941 		ret = usb_gadget_map_request(&dwc->gadget, &req->request,
942 				dep->number);
943 		if (ret) {
944 			dev_dbg(dwc->dev, "failed to map request\n");
945 			return;
946 		}
947 
948 		ret = dwc3_ep0_start_trans(dwc, dep->number, req->request.dma,
949 				req->request.length, DWC3_TRBCTL_CONTROL_DATA);
950 	}
951 
952 	WARN_ON(ret < 0);
953 }
954 
955 static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
956 {
957 	struct dwc3		*dwc = dep->dwc;
958 	u32			type;
959 
960 	type = dwc->three_stage_setup ? DWC3_TRBCTL_CONTROL_STATUS3
961 		: DWC3_TRBCTL_CONTROL_STATUS2;
962 
963 	return dwc3_ep0_start_trans(dwc, dep->number,
964 			dwc->ctrl_req_addr, 0, type);
965 }
966 
967 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)
968 {
969 	if (dwc->resize_fifos) {
970 		dev_dbg(dwc->dev, "Resizing FIFOs");
971 		dwc3_gadget_resize_tx_fifos(dwc);
972 		dwc->resize_fifos = 0;
973 	}
974 
975 	WARN_ON(dwc3_ep0_start_control_status(dep));
976 }
977 
978 static void dwc3_ep0_do_control_status(struct dwc3 *dwc,
979 		const struct dwc3_event_depevt *event)
980 {
981 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
982 
983 	__dwc3_ep0_do_control_status(dwc, dep);
984 }
985 
986 static void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep)
987 {
988 	struct dwc3_gadget_ep_cmd_params params;
989 	u32			cmd;
990 	int			ret;
991 
992 	if (!dep->resource_index)
993 		return;
994 
995 	cmd = DWC3_DEPCMD_ENDTRANSFER;
996 	cmd |= DWC3_DEPCMD_CMDIOC;
997 	cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
998 	memset(&params, 0, sizeof(params));
999 	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
1000 	WARN_ON_ONCE(ret);
1001 	dep->resource_index = 0;
1002 }
1003 
1004 static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
1005 		const struct dwc3_event_depevt *event)
1006 {
1007 	dwc->setup_packet_pending = true;
1008 
1009 	switch (event->status) {
1010 	case DEPEVT_STATUS_CONTROL_DATA:
1011 		dev_vdbg(dwc->dev, "Control Data");
1012 
1013 		/*
1014 		 * We already have a DATA transfer in the controller's cache,
1015 		 * if we receive a XferNotReady(DATA) we will ignore it, unless
1016 		 * it's for the wrong direction.
1017 		 *
1018 		 * In that case, we must issue END_TRANSFER command to the Data
1019 		 * Phase we already have started and issue SetStall on the
1020 		 * control endpoint.
1021 		 */
1022 		if (dwc->ep0_expect_in != event->endpoint_number) {
1023 			struct dwc3_ep	*dep = dwc->eps[dwc->ep0_expect_in];
1024 
1025 			dev_vdbg(dwc->dev, "Wrong direction for Data phase");
1026 			dwc3_ep0_end_control_data(dwc, dep);
1027 			dwc3_ep0_stall_and_restart(dwc);
1028 			return;
1029 		}
1030 
1031 		break;
1032 
1033 	case DEPEVT_STATUS_CONTROL_STATUS:
1034 		if (dwc->ep0_next_event != DWC3_EP0_NRDY_STATUS)
1035 			return;
1036 
1037 		dev_vdbg(dwc->dev, "Control Status");
1038 
1039 		dwc->ep0state = EP0_STATUS_PHASE;
1040 
1041 		if (dwc->delayed_status) {
1042 			WARN_ON_ONCE(event->endpoint_number != 1);
1043 			dev_vdbg(dwc->dev, "Delayed Status");
1044 			return;
1045 		}
1046 
1047 		dwc3_ep0_do_control_status(dwc, event);
1048 	}
1049 }
1050 
1051 void dwc3_ep0_interrupt(struct dwc3 *dwc,
1052 		const struct dwc3_event_depevt *event)
1053 {
1054 	u8			epnum = event->endpoint_number;
1055 
1056 	dev_dbg(dwc->dev, "%s while ep%d%s in state '%s'",
1057 			dwc3_ep_event_string(event->endpoint_event),
1058 			epnum >> 1, (epnum & 1) ? "in" : "out",
1059 			dwc3_ep0_state_string(dwc->ep0state));
1060 
1061 	switch (event->endpoint_event) {
1062 	case DWC3_DEPEVT_XFERCOMPLETE:
1063 		dwc3_ep0_xfer_complete(dwc, event);
1064 		break;
1065 
1066 	case DWC3_DEPEVT_XFERNOTREADY:
1067 		dwc3_ep0_xfernotready(dwc, event);
1068 		break;
1069 
1070 	case DWC3_DEPEVT_XFERINPROGRESS:
1071 	case DWC3_DEPEVT_RXTXFIFOEVT:
1072 	case DWC3_DEPEVT_STREAMEVT:
1073 	case DWC3_DEPEVT_EPCMDCMPLT:
1074 		break;
1075 	}
1076 }
1077