xref: /linux/drivers/usb/dwc3/ep0.c (revision 95e9fd10f06cb5642028b6b851e32b8c8afb4571)
1 /**
2  * ep0.c - DesignWare USB3 DRD Controller Endpoint 0 Handling
3  *
4  * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
5  *
6  * Authors: Felipe Balbi <balbi@ti.com>,
7  *	    Sebastian Andrzej Siewior <bigeasy@linutronix.de>
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions, and the following disclaimer,
14  *    without modification.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. The names of the above-listed copyright holders may not be used
19  *    to endorse or promote products derived from this software without
20  *    specific prior written permission.
21  *
22  * ALTERNATIVELY, this software may be distributed under the terms of the
23  * GNU General Public License ("GPL") version 2, as published by the Free
24  * Software Foundation.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
27  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
28  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
30  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
31  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
32  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
33  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
34  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
35  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
36  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <linux/kernel.h>
40 #include <linux/slab.h>
41 #include <linux/spinlock.h>
42 #include <linux/platform_device.h>
43 #include <linux/pm_runtime.h>
44 #include <linux/interrupt.h>
45 #include <linux/io.h>
46 #include <linux/list.h>
47 #include <linux/dma-mapping.h>
48 
49 #include <linux/usb/ch9.h>
50 #include <linux/usb/gadget.h>
51 #include <linux/usb/composite.h>
52 
53 #include "core.h"
54 #include "gadget.h"
55 #include "io.h"
56 
57 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep);
58 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
59 		struct dwc3_ep *dep, struct dwc3_request *req);
60 
61 static const char *dwc3_ep0_state_string(enum dwc3_ep0_state state)
62 {
63 	switch (state) {
64 	case EP0_UNCONNECTED:
65 		return "Unconnected";
66 	case EP0_SETUP_PHASE:
67 		return "Setup Phase";
68 	case EP0_DATA_PHASE:
69 		return "Data Phase";
70 	case EP0_STATUS_PHASE:
71 		return "Status Phase";
72 	default:
73 		return "UNKNOWN";
74 	}
75 }
76 
77 static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
78 		u32 len, u32 type)
79 {
80 	struct dwc3_gadget_ep_cmd_params params;
81 	struct dwc3_trb			*trb;
82 	struct dwc3_ep			*dep;
83 
84 	int				ret;
85 
86 	dep = dwc->eps[epnum];
87 	if (dep->flags & DWC3_EP_BUSY) {
88 		dev_vdbg(dwc->dev, "%s: still busy\n", dep->name);
89 		return 0;
90 	}
91 
92 	trb = dwc->ep0_trb;
93 
94 	trb->bpl = lower_32_bits(buf_dma);
95 	trb->bph = upper_32_bits(buf_dma);
96 	trb->size = len;
97 	trb->ctrl = type;
98 
99 	trb->ctrl |= (DWC3_TRB_CTRL_HWO
100 			| DWC3_TRB_CTRL_LST
101 			| DWC3_TRB_CTRL_IOC
102 			| DWC3_TRB_CTRL_ISP_IMI);
103 
104 	memset(&params, 0, sizeof(params));
105 	params.param0 = upper_32_bits(dwc->ep0_trb_addr);
106 	params.param1 = lower_32_bits(dwc->ep0_trb_addr);
107 
108 	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
109 			DWC3_DEPCMD_STARTTRANSFER, &params);
110 	if (ret < 0) {
111 		dev_dbg(dwc->dev, "failed to send STARTTRANSFER command\n");
112 		return ret;
113 	}
114 
115 	dep->flags |= DWC3_EP_BUSY;
116 	dep->resource_index = dwc3_gadget_ep_get_transfer_index(dwc,
117 			dep->number);
118 
119 	dwc->ep0_next_event = DWC3_EP0_COMPLETE;
120 
121 	return 0;
122 }
123 
124 static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep,
125 		struct dwc3_request *req)
126 {
127 	struct dwc3		*dwc = dep->dwc;
128 	int			ret = 0;
129 
130 	req->request.actual	= 0;
131 	req->request.status	= -EINPROGRESS;
132 	req->epnum		= dep->number;
133 
134 	list_add_tail(&req->list, &dep->request_list);
135 
136 	/*
137 	 * Gadget driver might not be quick enough to queue a request
138 	 * before we get a Transfer Not Ready event on this endpoint.
139 	 *
140 	 * In that case, we will set DWC3_EP_PENDING_REQUEST. When that
141 	 * flag is set, it's telling us that as soon as Gadget queues the
142 	 * required request, we should kick the transfer here because the
143 	 * IRQ we were waiting for is long gone.
144 	 */
145 	if (dep->flags & DWC3_EP_PENDING_REQUEST) {
146 		unsigned	direction;
147 
148 		direction = !!(dep->flags & DWC3_EP0_DIR_IN);
149 
150 		if (dwc->ep0state != EP0_DATA_PHASE) {
151 			dev_WARN(dwc->dev, "Unexpected pending request\n");
152 			return 0;
153 		}
154 
155 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
156 
157 		dep->flags &= ~(DWC3_EP_PENDING_REQUEST |
158 				DWC3_EP0_DIR_IN);
159 	} else if (dwc->delayed_status) {
160 		dwc->delayed_status = false;
161 
162 		if (dwc->ep0state == EP0_STATUS_PHASE)
163 			__dwc3_ep0_do_control_status(dwc, dwc->eps[1]);
164 		else
165 			dev_dbg(dwc->dev, "too early for delayed status\n");
166 	}
167 
168 	return ret;
169 }
170 
171 int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
172 		gfp_t gfp_flags)
173 {
174 	struct dwc3_request		*req = to_dwc3_request(request);
175 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
176 	struct dwc3			*dwc = dep->dwc;
177 
178 	unsigned long			flags;
179 
180 	int				ret;
181 
182 	spin_lock_irqsave(&dwc->lock, flags);
183 	if (!dep->endpoint.desc) {
184 		dev_dbg(dwc->dev, "trying to queue request %p to disabled %s\n",
185 				request, dep->name);
186 		ret = -ESHUTDOWN;
187 		goto out;
188 	}
189 
190 	/* we share one TRB for ep0/1 */
191 	if (!list_empty(&dep->request_list)) {
192 		ret = -EBUSY;
193 		goto out;
194 	}
195 
196 	dev_vdbg(dwc->dev, "queueing request %p to %s length %d, state '%s'\n",
197 			request, dep->name, request->length,
198 			dwc3_ep0_state_string(dwc->ep0state));
199 
200 	ret = __dwc3_gadget_ep0_queue(dep, req);
201 
202 out:
203 	spin_unlock_irqrestore(&dwc->lock, flags);
204 
205 	return ret;
206 }
207 
208 static void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
209 {
210 	struct dwc3_ep		*dep = dwc->eps[0];
211 
212 	/* stall is always issued on EP0 */
213 	__dwc3_gadget_ep_set_halt(dep, 1);
214 	dep->flags = DWC3_EP_ENABLED;
215 	dwc->delayed_status = false;
216 
217 	if (!list_empty(&dep->request_list)) {
218 		struct dwc3_request	*req;
219 
220 		req = next_request(&dep->request_list);
221 		dwc3_gadget_giveback(dep, req, -ECONNRESET);
222 	}
223 
224 	dwc->ep0state = EP0_SETUP_PHASE;
225 	dwc3_ep0_out_start(dwc);
226 }
227 
228 int dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
229 {
230 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
231 	struct dwc3			*dwc = dep->dwc;
232 
233 	dwc3_ep0_stall_and_restart(dwc);
234 
235 	return 0;
236 }
237 
238 void dwc3_ep0_out_start(struct dwc3 *dwc)
239 {
240 	int				ret;
241 
242 	ret = dwc3_ep0_start_trans(dwc, 0, dwc->ctrl_req_addr, 8,
243 			DWC3_TRBCTL_CONTROL_SETUP);
244 	WARN_ON(ret < 0);
245 }
246 
247 static struct dwc3_ep *dwc3_wIndex_to_dep(struct dwc3 *dwc, __le16 wIndex_le)
248 {
249 	struct dwc3_ep		*dep;
250 	u32			windex = le16_to_cpu(wIndex_le);
251 	u32			epnum;
252 
253 	epnum = (windex & USB_ENDPOINT_NUMBER_MASK) << 1;
254 	if ((windex & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN)
255 		epnum |= 1;
256 
257 	dep = dwc->eps[epnum];
258 	if (dep->flags & DWC3_EP_ENABLED)
259 		return dep;
260 
261 	return NULL;
262 }
263 
264 static void dwc3_ep0_status_cmpl(struct usb_ep *ep, struct usb_request *req)
265 {
266 }
267 /*
268  * ch 9.4.5
269  */
270 static int dwc3_ep0_handle_status(struct dwc3 *dwc,
271 		struct usb_ctrlrequest *ctrl)
272 {
273 	struct dwc3_ep		*dep;
274 	u32			recip;
275 	u32			reg;
276 	u16			usb_status = 0;
277 	__le16			*response_pkt;
278 
279 	recip = ctrl->bRequestType & USB_RECIP_MASK;
280 	switch (recip) {
281 	case USB_RECIP_DEVICE:
282 		/*
283 		 * LTM will be set once we know how to set this in HW.
284 		 */
285 		usb_status |= dwc->is_selfpowered << USB_DEVICE_SELF_POWERED;
286 
287 		if (dwc->speed == DWC3_DSTS_SUPERSPEED) {
288 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
289 			if (reg & DWC3_DCTL_INITU1ENA)
290 				usb_status |= 1 << USB_DEV_STAT_U1_ENABLED;
291 			if (reg & DWC3_DCTL_INITU2ENA)
292 				usb_status |= 1 << USB_DEV_STAT_U2_ENABLED;
293 		}
294 
295 		break;
296 
297 	case USB_RECIP_INTERFACE:
298 		/*
299 		 * Function Remote Wake Capable	D0
300 		 * Function Remote Wakeup	D1
301 		 */
302 		break;
303 
304 	case USB_RECIP_ENDPOINT:
305 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
306 		if (!dep)
307 			return -EINVAL;
308 
309 		if (dep->flags & DWC3_EP_STALL)
310 			usb_status = 1 << USB_ENDPOINT_HALT;
311 		break;
312 	default:
313 		return -EINVAL;
314 	};
315 
316 	response_pkt = (__le16 *) dwc->setup_buf;
317 	*response_pkt = cpu_to_le16(usb_status);
318 
319 	dep = dwc->eps[0];
320 	dwc->ep0_usb_req.dep = dep;
321 	dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
322 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
323 	dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
324 
325 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
326 }
327 
328 static int dwc3_ep0_handle_feature(struct dwc3 *dwc,
329 		struct usb_ctrlrequest *ctrl, int set)
330 {
331 	struct dwc3_ep		*dep;
332 	u32			recip;
333 	u32			wValue;
334 	u32			wIndex;
335 	u32			reg;
336 	int			ret;
337 
338 	wValue = le16_to_cpu(ctrl->wValue);
339 	wIndex = le16_to_cpu(ctrl->wIndex);
340 	recip = ctrl->bRequestType & USB_RECIP_MASK;
341 	switch (recip) {
342 	case USB_RECIP_DEVICE:
343 
344 		switch (wValue) {
345 		case USB_DEVICE_REMOTE_WAKEUP:
346 			break;
347 		/*
348 		 * 9.4.1 says only only for SS, in AddressState only for
349 		 * default control pipe
350 		 */
351 		case USB_DEVICE_U1_ENABLE:
352 			if (dwc->dev_state != DWC3_CONFIGURED_STATE)
353 				return -EINVAL;
354 			if (dwc->speed != DWC3_DSTS_SUPERSPEED)
355 				return -EINVAL;
356 
357 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
358 			if (set)
359 				reg |= DWC3_DCTL_INITU1ENA;
360 			else
361 				reg &= ~DWC3_DCTL_INITU1ENA;
362 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
363 			break;
364 
365 		case USB_DEVICE_U2_ENABLE:
366 			if (dwc->dev_state != DWC3_CONFIGURED_STATE)
367 				return -EINVAL;
368 			if (dwc->speed != DWC3_DSTS_SUPERSPEED)
369 				return -EINVAL;
370 
371 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
372 			if (set)
373 				reg |= DWC3_DCTL_INITU2ENA;
374 			else
375 				reg &= ~DWC3_DCTL_INITU2ENA;
376 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
377 			break;
378 
379 		case USB_DEVICE_LTM_ENABLE:
380 			return -EINVAL;
381 			break;
382 
383 		case USB_DEVICE_TEST_MODE:
384 			if ((wIndex & 0xff) != 0)
385 				return -EINVAL;
386 			if (!set)
387 				return -EINVAL;
388 
389 			dwc->test_mode_nr = wIndex >> 8;
390 			dwc->test_mode = true;
391 			break;
392 		default:
393 			return -EINVAL;
394 		}
395 		break;
396 
397 	case USB_RECIP_INTERFACE:
398 		switch (wValue) {
399 		case USB_INTRF_FUNC_SUSPEND:
400 			if (wIndex & USB_INTRF_FUNC_SUSPEND_LP)
401 				/* XXX enable Low power suspend */
402 				;
403 			if (wIndex & USB_INTRF_FUNC_SUSPEND_RW)
404 				/* XXX enable remote wakeup */
405 				;
406 			break;
407 		default:
408 			return -EINVAL;
409 		}
410 		break;
411 
412 	case USB_RECIP_ENDPOINT:
413 		switch (wValue) {
414 		case USB_ENDPOINT_HALT:
415 			dep = dwc3_wIndex_to_dep(dwc, wIndex);
416 			if (!dep)
417 				return -EINVAL;
418 			ret = __dwc3_gadget_ep_set_halt(dep, set);
419 			if (ret)
420 				return -EINVAL;
421 			break;
422 		default:
423 			return -EINVAL;
424 		}
425 		break;
426 
427 	default:
428 		return -EINVAL;
429 	};
430 
431 	return 0;
432 }
433 
434 static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
435 {
436 	u32 addr;
437 	u32 reg;
438 
439 	addr = le16_to_cpu(ctrl->wValue);
440 	if (addr > 127) {
441 		dev_dbg(dwc->dev, "invalid device address %d\n", addr);
442 		return -EINVAL;
443 	}
444 
445 	if (dwc->dev_state == DWC3_CONFIGURED_STATE) {
446 		dev_dbg(dwc->dev, "trying to set address when configured\n");
447 		return -EINVAL;
448 	}
449 
450 	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
451 	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
452 	reg |= DWC3_DCFG_DEVADDR(addr);
453 	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
454 
455 	if (addr)
456 		dwc->dev_state = DWC3_ADDRESS_STATE;
457 	else
458 		dwc->dev_state = DWC3_DEFAULT_STATE;
459 
460 	return 0;
461 }
462 
463 static int dwc3_ep0_delegate_req(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
464 {
465 	int ret;
466 
467 	spin_unlock(&dwc->lock);
468 	ret = dwc->gadget_driver->setup(&dwc->gadget, ctrl);
469 	spin_lock(&dwc->lock);
470 	return ret;
471 }
472 
473 static int dwc3_ep0_set_config(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
474 {
475 	u32 cfg;
476 	int ret;
477 	u32 reg;
478 
479 	dwc->start_config_issued = false;
480 	cfg = le16_to_cpu(ctrl->wValue);
481 
482 	switch (dwc->dev_state) {
483 	case DWC3_DEFAULT_STATE:
484 		return -EINVAL;
485 		break;
486 
487 	case DWC3_ADDRESS_STATE:
488 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
489 		/* if the cfg matches and the cfg is non zero */
490 		if (cfg && (!ret || (ret == USB_GADGET_DELAYED_STATUS))) {
491 			dwc->dev_state = DWC3_CONFIGURED_STATE;
492 			/*
493 			 * Enable transition to U1/U2 state when
494 			 * nothing is pending from application.
495 			 */
496 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
497 			reg |= (DWC3_DCTL_ACCEPTU1ENA | DWC3_DCTL_ACCEPTU2ENA);
498 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
499 
500 			dwc->resize_fifos = true;
501 			dev_dbg(dwc->dev, "resize fifos flag SET\n");
502 		}
503 		break;
504 
505 	case DWC3_CONFIGURED_STATE:
506 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
507 		if (!cfg)
508 			dwc->dev_state = DWC3_ADDRESS_STATE;
509 		break;
510 	default:
511 		ret = -EINVAL;
512 	}
513 	return ret;
514 }
515 
516 static void dwc3_ep0_set_sel_cmpl(struct usb_ep *ep, struct usb_request *req)
517 {
518 	struct dwc3_ep	*dep = to_dwc3_ep(ep);
519 	struct dwc3	*dwc = dep->dwc;
520 
521 	u32		param = 0;
522 	u32		reg;
523 
524 	struct timing {
525 		u8	u1sel;
526 		u8	u1pel;
527 		u16	u2sel;
528 		u16	u2pel;
529 	} __packed timing;
530 
531 	int		ret;
532 
533 	memcpy(&timing, req->buf, sizeof(timing));
534 
535 	dwc->u1sel = timing.u1sel;
536 	dwc->u1pel = timing.u1pel;
537 	dwc->u2sel = le16_to_cpu(timing.u2sel);
538 	dwc->u2pel = le16_to_cpu(timing.u2pel);
539 
540 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
541 	if (reg & DWC3_DCTL_INITU2ENA)
542 		param = dwc->u2pel;
543 	if (reg & DWC3_DCTL_INITU1ENA)
544 		param = dwc->u1pel;
545 
546 	/*
547 	 * According to Synopsys Databook, if parameter is
548 	 * greater than 125, a value of zero should be
549 	 * programmed in the register.
550 	 */
551 	if (param > 125)
552 		param = 0;
553 
554 	/* now that we have the time, issue DGCMD Set Sel */
555 	ret = dwc3_send_gadget_generic_command(dwc,
556 			DWC3_DGCMD_SET_PERIODIC_PAR, param);
557 	WARN_ON(ret < 0);
558 }
559 
560 static int dwc3_ep0_set_sel(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
561 {
562 	struct dwc3_ep	*dep;
563 	u16		wLength;
564 	u16		wValue;
565 
566 	if (dwc->dev_state == DWC3_DEFAULT_STATE)
567 		return -EINVAL;
568 
569 	wValue = le16_to_cpu(ctrl->wValue);
570 	wLength = le16_to_cpu(ctrl->wLength);
571 
572 	if (wLength != 6) {
573 		dev_err(dwc->dev, "Set SEL should be 6 bytes, got %d\n",
574 				wLength);
575 		return -EINVAL;
576 	}
577 
578 	/*
579 	 * To handle Set SEL we need to receive 6 bytes from Host. So let's
580 	 * queue a usb_request for 6 bytes.
581 	 *
582 	 * Remember, though, this controller can't handle non-wMaxPacketSize
583 	 * aligned transfers on the OUT direction, so we queue a request for
584 	 * wMaxPacketSize instead.
585 	 */
586 	dep = dwc->eps[0];
587 	dwc->ep0_usb_req.dep = dep;
588 	dwc->ep0_usb_req.request.length = dep->endpoint.maxpacket;
589 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
590 	dwc->ep0_usb_req.request.complete = dwc3_ep0_set_sel_cmpl;
591 
592 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
593 }
594 
595 static int dwc3_ep0_set_isoch_delay(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
596 {
597 	u16		wLength;
598 	u16		wValue;
599 	u16		wIndex;
600 
601 	wValue = le16_to_cpu(ctrl->wValue);
602 	wLength = le16_to_cpu(ctrl->wLength);
603 	wIndex = le16_to_cpu(ctrl->wIndex);
604 
605 	if (wIndex || wLength)
606 		return -EINVAL;
607 
608 	/*
609 	 * REVISIT It's unclear from Databook what to do with this
610 	 * value. For now, just cache it.
611 	 */
612 	dwc->isoch_delay = wValue;
613 
614 	return 0;
615 }
616 
617 static int dwc3_ep0_std_request(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
618 {
619 	int ret;
620 
621 	switch (ctrl->bRequest) {
622 	case USB_REQ_GET_STATUS:
623 		dev_vdbg(dwc->dev, "USB_REQ_GET_STATUS\n");
624 		ret = dwc3_ep0_handle_status(dwc, ctrl);
625 		break;
626 	case USB_REQ_CLEAR_FEATURE:
627 		dev_vdbg(dwc->dev, "USB_REQ_CLEAR_FEATURE\n");
628 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 0);
629 		break;
630 	case USB_REQ_SET_FEATURE:
631 		dev_vdbg(dwc->dev, "USB_REQ_SET_FEATURE\n");
632 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 1);
633 		break;
634 	case USB_REQ_SET_ADDRESS:
635 		dev_vdbg(dwc->dev, "USB_REQ_SET_ADDRESS\n");
636 		ret = dwc3_ep0_set_address(dwc, ctrl);
637 		break;
638 	case USB_REQ_SET_CONFIGURATION:
639 		dev_vdbg(dwc->dev, "USB_REQ_SET_CONFIGURATION\n");
640 		ret = dwc3_ep0_set_config(dwc, ctrl);
641 		break;
642 	case USB_REQ_SET_SEL:
643 		dev_vdbg(dwc->dev, "USB_REQ_SET_SEL\n");
644 		ret = dwc3_ep0_set_sel(dwc, ctrl);
645 		break;
646 	case USB_REQ_SET_ISOCH_DELAY:
647 		dev_vdbg(dwc->dev, "USB_REQ_SET_ISOCH_DELAY\n");
648 		ret = dwc3_ep0_set_isoch_delay(dwc, ctrl);
649 		break;
650 	default:
651 		dev_vdbg(dwc->dev, "Forwarding to gadget driver\n");
652 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
653 		break;
654 	};
655 
656 	return ret;
657 }
658 
659 static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
660 		const struct dwc3_event_depevt *event)
661 {
662 	struct usb_ctrlrequest *ctrl = dwc->ctrl_req;
663 	int ret = -EINVAL;
664 	u32 len;
665 
666 	if (!dwc->gadget_driver)
667 		goto out;
668 
669 	len = le16_to_cpu(ctrl->wLength);
670 	if (!len) {
671 		dwc->three_stage_setup = false;
672 		dwc->ep0_expect_in = false;
673 		dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
674 	} else {
675 		dwc->three_stage_setup = true;
676 		dwc->ep0_expect_in = !!(ctrl->bRequestType & USB_DIR_IN);
677 		dwc->ep0_next_event = DWC3_EP0_NRDY_DATA;
678 	}
679 
680 	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
681 		ret = dwc3_ep0_std_request(dwc, ctrl);
682 	else
683 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
684 
685 	if (ret == USB_GADGET_DELAYED_STATUS)
686 		dwc->delayed_status = true;
687 
688 out:
689 	if (ret < 0)
690 		dwc3_ep0_stall_and_restart(dwc);
691 }
692 
693 static void dwc3_ep0_complete_data(struct dwc3 *dwc,
694 		const struct dwc3_event_depevt *event)
695 {
696 	struct dwc3_request	*r = NULL;
697 	struct usb_request	*ur;
698 	struct dwc3_trb		*trb;
699 	struct dwc3_ep		*ep0;
700 	u32			transferred;
701 	u32			length;
702 	u8			epnum;
703 
704 	epnum = event->endpoint_number;
705 	ep0 = dwc->eps[0];
706 
707 	dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
708 
709 	r = next_request(&ep0->request_list);
710 	ur = &r->request;
711 
712 	trb = dwc->ep0_trb;
713 	length = trb->size & DWC3_TRB_SIZE_MASK;
714 
715 	if (dwc->ep0_bounced) {
716 		unsigned transfer_size = ur->length;
717 		unsigned maxp = ep0->endpoint.maxpacket;
718 
719 		transfer_size += (maxp - (transfer_size % maxp));
720 		transferred = min_t(u32, ur->length,
721 				transfer_size - length);
722 		memcpy(ur->buf, dwc->ep0_bounce, transferred);
723 		dwc->ep0_bounced = false;
724 	} else {
725 		transferred = ur->length - length;
726 	}
727 
728 	ur->actual += transferred;
729 
730 	if ((epnum & 1) && ur->actual < ur->length) {
731 		/* for some reason we did not get everything out */
732 
733 		dwc3_ep0_stall_and_restart(dwc);
734 	} else {
735 		/*
736 		 * handle the case where we have to send a zero packet. This
737 		 * seems to be case when req.length > maxpacket. Could it be?
738 		 */
739 		if (r)
740 			dwc3_gadget_giveback(ep0, r, 0);
741 	}
742 }
743 
744 static void dwc3_ep0_complete_status(struct dwc3 *dwc,
745 		const struct dwc3_event_depevt *event)
746 {
747 	struct dwc3_request	*r;
748 	struct dwc3_ep		*dep;
749 
750 	dep = dwc->eps[0];
751 
752 	if (!list_empty(&dep->request_list)) {
753 		r = next_request(&dep->request_list);
754 
755 		dwc3_gadget_giveback(dep, r, 0);
756 	}
757 
758 	if (dwc->test_mode) {
759 		int ret;
760 
761 		ret = dwc3_gadget_set_test_mode(dwc, dwc->test_mode_nr);
762 		if (ret < 0) {
763 			dev_dbg(dwc->dev, "Invalid Test #%d\n",
764 					dwc->test_mode_nr);
765 			dwc3_ep0_stall_and_restart(dwc);
766 			return;
767 		}
768 	}
769 
770 	dwc->ep0state = EP0_SETUP_PHASE;
771 	dwc3_ep0_out_start(dwc);
772 }
773 
774 static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
775 			const struct dwc3_event_depevt *event)
776 {
777 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
778 
779 	dep->flags &= ~DWC3_EP_BUSY;
780 	dep->resource_index = 0;
781 	dwc->setup_packet_pending = false;
782 
783 	switch (dwc->ep0state) {
784 	case EP0_SETUP_PHASE:
785 		dev_vdbg(dwc->dev, "Inspecting Setup Bytes\n");
786 		dwc3_ep0_inspect_setup(dwc, event);
787 		break;
788 
789 	case EP0_DATA_PHASE:
790 		dev_vdbg(dwc->dev, "Data Phase\n");
791 		dwc3_ep0_complete_data(dwc, event);
792 		break;
793 
794 	case EP0_STATUS_PHASE:
795 		dev_vdbg(dwc->dev, "Status Phase\n");
796 		dwc3_ep0_complete_status(dwc, event);
797 		break;
798 	default:
799 		WARN(true, "UNKNOWN ep0state %d\n", dwc->ep0state);
800 	}
801 }
802 
803 static void dwc3_ep0_do_control_setup(struct dwc3 *dwc,
804 		const struct dwc3_event_depevt *event)
805 {
806 	dwc3_ep0_out_start(dwc);
807 }
808 
809 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
810 		struct dwc3_ep *dep, struct dwc3_request *req)
811 {
812 	int			ret;
813 
814 	req->direction = !!dep->number;
815 
816 	if (req->request.length == 0) {
817 		ret = dwc3_ep0_start_trans(dwc, dep->number,
818 				dwc->ctrl_req_addr, 0,
819 				DWC3_TRBCTL_CONTROL_DATA);
820 	} else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
821 			&& (dep->number == 0)) {
822 		u32		transfer_size;
823 
824 		ret = usb_gadget_map_request(&dwc->gadget, &req->request,
825 				dep->number);
826 		if (ret) {
827 			dev_dbg(dwc->dev, "failed to map request\n");
828 			return;
829 		}
830 
831 		WARN_ON(req->request.length > DWC3_EP0_BOUNCE_SIZE);
832 
833 		transfer_size = roundup(req->request.length,
834 				(u32) dep->endpoint.maxpacket);
835 
836 		dwc->ep0_bounced = true;
837 
838 		/*
839 		 * REVISIT in case request length is bigger than
840 		 * DWC3_EP0_BOUNCE_SIZE we will need two chained
841 		 * TRBs to handle the transfer.
842 		 */
843 		ret = dwc3_ep0_start_trans(dwc, dep->number,
844 				dwc->ep0_bounce_addr, transfer_size,
845 				DWC3_TRBCTL_CONTROL_DATA);
846 	} else {
847 		ret = usb_gadget_map_request(&dwc->gadget, &req->request,
848 				dep->number);
849 		if (ret) {
850 			dev_dbg(dwc->dev, "failed to map request\n");
851 			return;
852 		}
853 
854 		ret = dwc3_ep0_start_trans(dwc, dep->number, req->request.dma,
855 				req->request.length, DWC3_TRBCTL_CONTROL_DATA);
856 	}
857 
858 	WARN_ON(ret < 0);
859 }
860 
861 static void dwc3_ep0_do_control_data(struct dwc3 *dwc,
862 		const struct dwc3_event_depevt *event)
863 {
864 	struct dwc3_ep		*dep;
865 	struct dwc3_request	*req;
866 
867 	dep = dwc->eps[0];
868 
869 	if (list_empty(&dep->request_list)) {
870 		dev_vdbg(dwc->dev, "pending request for EP0 Data phase\n");
871 		dep->flags |= DWC3_EP_PENDING_REQUEST;
872 
873 		if (event->endpoint_number)
874 			dep->flags |= DWC3_EP0_DIR_IN;
875 		return;
876 	}
877 
878 	req = next_request(&dep->request_list);
879 	dep = dwc->eps[event->endpoint_number];
880 
881 	__dwc3_ep0_do_control_data(dwc, dep, req);
882 }
883 
884 static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
885 {
886 	struct dwc3		*dwc = dep->dwc;
887 	u32			type;
888 
889 	type = dwc->three_stage_setup ? DWC3_TRBCTL_CONTROL_STATUS3
890 		: DWC3_TRBCTL_CONTROL_STATUS2;
891 
892 	return dwc3_ep0_start_trans(dwc, dep->number,
893 			dwc->ctrl_req_addr, 0, type);
894 }
895 
896 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)
897 {
898 	if (dwc->resize_fifos) {
899 		dev_dbg(dwc->dev, "starting to resize fifos\n");
900 		dwc3_gadget_resize_tx_fifos(dwc);
901 		dwc->resize_fifos = 0;
902 	}
903 
904 	WARN_ON(dwc3_ep0_start_control_status(dep));
905 }
906 
907 static void dwc3_ep0_do_control_status(struct dwc3 *dwc,
908 		const struct dwc3_event_depevt *event)
909 {
910 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
911 
912 	__dwc3_ep0_do_control_status(dwc, dep);
913 }
914 
915 static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
916 		const struct dwc3_event_depevt *event)
917 {
918 	dwc->setup_packet_pending = true;
919 
920 	/*
921 	 * This part is very tricky: If we have just handled
922 	 * XferNotReady(Setup) and we're now expecting a
923 	 * XferComplete but, instead, we receive another
924 	 * XferNotReady(Setup), we should STALL and restart
925 	 * the state machine.
926 	 *
927 	 * In all other cases, we just continue waiting
928 	 * for the XferComplete event.
929 	 *
930 	 * We are a little bit unsafe here because we're
931 	 * not trying to ensure that last event was, indeed,
932 	 * XferNotReady(Setup).
933 	 *
934 	 * Still, we don't expect any condition where that
935 	 * should happen and, even if it does, it would be
936 	 * another error condition.
937 	 */
938 	if (dwc->ep0_next_event == DWC3_EP0_COMPLETE) {
939 		switch (event->status) {
940 		case DEPEVT_STATUS_CONTROL_SETUP:
941 			dev_vdbg(dwc->dev, "Unexpected XferNotReady(Setup)\n");
942 			dwc3_ep0_stall_and_restart(dwc);
943 			break;
944 		case DEPEVT_STATUS_CONTROL_DATA:
945 			/* FALLTHROUGH */
946 		case DEPEVT_STATUS_CONTROL_STATUS:
947 			/* FALLTHROUGH */
948 		default:
949 			dev_vdbg(dwc->dev, "waiting for XferComplete\n");
950 		}
951 
952 		return;
953 	}
954 
955 	switch (event->status) {
956 	case DEPEVT_STATUS_CONTROL_SETUP:
957 		dev_vdbg(dwc->dev, "Control Setup\n");
958 
959 		dwc->ep0state = EP0_SETUP_PHASE;
960 
961 		dwc3_ep0_do_control_setup(dwc, event);
962 		break;
963 
964 	case DEPEVT_STATUS_CONTROL_DATA:
965 		dev_vdbg(dwc->dev, "Control Data\n");
966 
967 		dwc->ep0state = EP0_DATA_PHASE;
968 
969 		if (dwc->ep0_next_event != DWC3_EP0_NRDY_DATA) {
970 			dev_vdbg(dwc->dev, "Expected %d got %d\n",
971 					dwc->ep0_next_event,
972 					DWC3_EP0_NRDY_DATA);
973 
974 			dwc3_ep0_stall_and_restart(dwc);
975 			return;
976 		}
977 
978 		/*
979 		 * One of the possible error cases is when Host _does_
980 		 * request for Data Phase, but it does so on the wrong
981 		 * direction.
982 		 *
983 		 * Here, we already know ep0_next_event is DATA (see above),
984 		 * so we only need to check for direction.
985 		 */
986 		if (dwc->ep0_expect_in != event->endpoint_number) {
987 			dev_vdbg(dwc->dev, "Wrong direction for Data phase\n");
988 			dwc3_ep0_stall_and_restart(dwc);
989 			return;
990 		}
991 
992 		dwc3_ep0_do_control_data(dwc, event);
993 		break;
994 
995 	case DEPEVT_STATUS_CONTROL_STATUS:
996 		dev_vdbg(dwc->dev, "Control Status\n");
997 
998 		dwc->ep0state = EP0_STATUS_PHASE;
999 
1000 		if (dwc->ep0_next_event != DWC3_EP0_NRDY_STATUS) {
1001 			dev_vdbg(dwc->dev, "Expected %d got %d\n",
1002 					dwc->ep0_next_event,
1003 					DWC3_EP0_NRDY_STATUS);
1004 
1005 			dwc3_ep0_stall_and_restart(dwc);
1006 			return;
1007 		}
1008 
1009 		if (dwc->delayed_status) {
1010 			WARN_ON_ONCE(event->endpoint_number != 1);
1011 			dev_vdbg(dwc->dev, "Mass Storage delayed status\n");
1012 			return;
1013 		}
1014 
1015 		dwc3_ep0_do_control_status(dwc, event);
1016 	}
1017 }
1018 
1019 void dwc3_ep0_interrupt(struct dwc3 *dwc,
1020 		const struct dwc3_event_depevt *event)
1021 {
1022 	u8			epnum = event->endpoint_number;
1023 
1024 	dev_dbg(dwc->dev, "%s while ep%d%s in state '%s'\n",
1025 			dwc3_ep_event_string(event->endpoint_event),
1026 			epnum >> 1, (epnum & 1) ? "in" : "out",
1027 			dwc3_ep0_state_string(dwc->ep0state));
1028 
1029 	switch (event->endpoint_event) {
1030 	case DWC3_DEPEVT_XFERCOMPLETE:
1031 		dwc3_ep0_xfer_complete(dwc, event);
1032 		break;
1033 
1034 	case DWC3_DEPEVT_XFERNOTREADY:
1035 		dwc3_ep0_xfernotready(dwc, event);
1036 		break;
1037 
1038 	case DWC3_DEPEVT_XFERINPROGRESS:
1039 	case DWC3_DEPEVT_RXTXFIFOEVT:
1040 	case DWC3_DEPEVT_STREAMEVT:
1041 	case DWC3_DEPEVT_EPCMDCMPLT:
1042 		break;
1043 	}
1044 }
1045