xref: /linux/drivers/usb/dwc3/ep0.c (revision 861e10be08c69808065d755d3e3cab5d520a2d32)
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 
129 	req->request.actual	= 0;
130 	req->request.status	= -EINPROGRESS;
131 	req->epnum		= dep->number;
132 
133 	list_add_tail(&req->list, &dep->request_list);
134 
135 	/*
136 	 * Gadget driver might not be quick enough to queue a request
137 	 * before we get a Transfer Not Ready event on this endpoint.
138 	 *
139 	 * In that case, we will set DWC3_EP_PENDING_REQUEST. When that
140 	 * flag is set, it's telling us that as soon as Gadget queues the
141 	 * required request, we should kick the transfer here because the
142 	 * IRQ we were waiting for is long gone.
143 	 */
144 	if (dep->flags & DWC3_EP_PENDING_REQUEST) {
145 		unsigned	direction;
146 
147 		direction = !!(dep->flags & DWC3_EP0_DIR_IN);
148 
149 		if (dwc->ep0state != EP0_DATA_PHASE) {
150 			dev_WARN(dwc->dev, "Unexpected pending request\n");
151 			return 0;
152 		}
153 
154 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
155 
156 		dep->flags &= ~(DWC3_EP_PENDING_REQUEST |
157 				DWC3_EP0_DIR_IN);
158 
159 		return 0;
160 	}
161 
162 	/*
163 	 * In case gadget driver asked us to delay the STATUS phase,
164 	 * handle it here.
165 	 */
166 	if (dwc->delayed_status) {
167 		unsigned	direction;
168 
169 		direction = !dwc->ep0_expect_in;
170 		dwc->delayed_status = false;
171 
172 		if (dwc->ep0state == EP0_STATUS_PHASE)
173 			__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
174 		else
175 			dev_dbg(dwc->dev, "too early for delayed status\n");
176 
177 		return 0;
178 	}
179 
180 	/*
181 	 * Unfortunately we have uncovered a limitation wrt the Data Phase.
182 	 *
183 	 * Section 9.4 says we can wait for the XferNotReady(DATA) event to
184 	 * come before issueing Start Transfer command, but if we do, we will
185 	 * miss situations where the host starts another SETUP phase instead of
186 	 * the DATA phase.  Such cases happen at least on TD.7.6 of the Link
187 	 * Layer Compliance Suite.
188 	 *
189 	 * The problem surfaces due to the fact that in case of back-to-back
190 	 * SETUP packets there will be no XferNotReady(DATA) generated and we
191 	 * will be stuck waiting for XferNotReady(DATA) forever.
192 	 *
193 	 * By looking at tables 9-13 and 9-14 of the Databook, we can see that
194 	 * it tells us to start Data Phase right away. It also mentions that if
195 	 * we receive a SETUP phase instead of the DATA phase, core will issue
196 	 * XferComplete for the DATA phase, before actually initiating it in
197 	 * the wire, with the TRB's status set to "SETUP_PENDING". Such status
198 	 * can only be used to print some debugging logs, as the core expects
199 	 * us to go through to the STATUS phase and start a CONTROL_STATUS TRB,
200 	 * just so it completes right away, without transferring anything and,
201 	 * only then, we can go back to the SETUP phase.
202 	 *
203 	 * Because of this scenario, SNPS decided to change the programming
204 	 * model of control transfers and support on-demand transfers only for
205 	 * the STATUS phase. To fix the issue we have now, we will always wait
206 	 * for gadget driver to queue the DATA phase's struct usb_request, then
207 	 * start it right away.
208 	 *
209 	 * If we're actually in a 2-stage transfer, we will wait for
210 	 * XferNotReady(STATUS).
211 	 */
212 	if (dwc->three_stage_setup) {
213 		unsigned        direction;
214 
215 		direction = dwc->ep0_expect_in;
216 		dwc->ep0state = EP0_DATA_PHASE;
217 
218 		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction], req);
219 
220 		dep->flags &= ~DWC3_EP0_DIR_IN;
221 	}
222 
223 	return 0;
224 }
225 
226 int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
227 		gfp_t gfp_flags)
228 {
229 	struct dwc3_request		*req = to_dwc3_request(request);
230 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
231 	struct dwc3			*dwc = dep->dwc;
232 
233 	unsigned long			flags;
234 
235 	int				ret;
236 
237 	spin_lock_irqsave(&dwc->lock, flags);
238 	if (!dep->endpoint.desc) {
239 		dev_dbg(dwc->dev, "trying to queue request %p to disabled %s\n",
240 				request, dep->name);
241 		ret = -ESHUTDOWN;
242 		goto out;
243 	}
244 
245 	/* we share one TRB for ep0/1 */
246 	if (!list_empty(&dep->request_list)) {
247 		ret = -EBUSY;
248 		goto out;
249 	}
250 
251 	dev_vdbg(dwc->dev, "queueing request %p to %s length %d, state '%s'\n",
252 			request, dep->name, request->length,
253 			dwc3_ep0_state_string(dwc->ep0state));
254 
255 	ret = __dwc3_gadget_ep0_queue(dep, req);
256 
257 out:
258 	spin_unlock_irqrestore(&dwc->lock, flags);
259 
260 	return ret;
261 }
262 
263 static void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
264 {
265 	struct dwc3_ep		*dep;
266 
267 	/* reinitialize physical ep1 */
268 	dep = dwc->eps[1];
269 	dep->flags = DWC3_EP_ENABLED;
270 
271 	/* stall is always issued on EP0 */
272 	dep = dwc->eps[0];
273 	__dwc3_gadget_ep_set_halt(dep, 1);
274 	dep->flags = DWC3_EP_ENABLED;
275 	dwc->delayed_status = false;
276 
277 	if (!list_empty(&dep->request_list)) {
278 		struct dwc3_request	*req;
279 
280 		req = next_request(&dep->request_list);
281 		dwc3_gadget_giveback(dep, req, -ECONNRESET);
282 	}
283 
284 	dwc->ep0state = EP0_SETUP_PHASE;
285 	dwc3_ep0_out_start(dwc);
286 }
287 
288 int dwc3_gadget_ep0_set_halt(struct usb_ep *ep, int value)
289 {
290 	struct dwc3_ep			*dep = to_dwc3_ep(ep);
291 	struct dwc3			*dwc = dep->dwc;
292 
293 	dwc3_ep0_stall_and_restart(dwc);
294 
295 	return 0;
296 }
297 
298 void dwc3_ep0_out_start(struct dwc3 *dwc)
299 {
300 	int				ret;
301 
302 	ret = dwc3_ep0_start_trans(dwc, 0, dwc->ctrl_req_addr, 8,
303 			DWC3_TRBCTL_CONTROL_SETUP);
304 	WARN_ON(ret < 0);
305 }
306 
307 static struct dwc3_ep *dwc3_wIndex_to_dep(struct dwc3 *dwc, __le16 wIndex_le)
308 {
309 	struct dwc3_ep		*dep;
310 	u32			windex = le16_to_cpu(wIndex_le);
311 	u32			epnum;
312 
313 	epnum = (windex & USB_ENDPOINT_NUMBER_MASK) << 1;
314 	if ((windex & USB_ENDPOINT_DIR_MASK) == USB_DIR_IN)
315 		epnum |= 1;
316 
317 	dep = dwc->eps[epnum];
318 	if (dep->flags & DWC3_EP_ENABLED)
319 		return dep;
320 
321 	return NULL;
322 }
323 
324 static void dwc3_ep0_status_cmpl(struct usb_ep *ep, struct usb_request *req)
325 {
326 }
327 /*
328  * ch 9.4.5
329  */
330 static int dwc3_ep0_handle_status(struct dwc3 *dwc,
331 		struct usb_ctrlrequest *ctrl)
332 {
333 	struct dwc3_ep		*dep;
334 	u32			recip;
335 	u32			reg;
336 	u16			usb_status = 0;
337 	__le16			*response_pkt;
338 
339 	recip = ctrl->bRequestType & USB_RECIP_MASK;
340 	switch (recip) {
341 	case USB_RECIP_DEVICE:
342 		/*
343 		 * LTM will be set once we know how to set this in HW.
344 		 */
345 		usb_status |= dwc->is_selfpowered << USB_DEVICE_SELF_POWERED;
346 
347 		if (dwc->speed == DWC3_DSTS_SUPERSPEED) {
348 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
349 			if (reg & DWC3_DCTL_INITU1ENA)
350 				usb_status |= 1 << USB_DEV_STAT_U1_ENABLED;
351 			if (reg & DWC3_DCTL_INITU2ENA)
352 				usb_status |= 1 << USB_DEV_STAT_U2_ENABLED;
353 		}
354 
355 		break;
356 
357 	case USB_RECIP_INTERFACE:
358 		/*
359 		 * Function Remote Wake Capable	D0
360 		 * Function Remote Wakeup	D1
361 		 */
362 		break;
363 
364 	case USB_RECIP_ENDPOINT:
365 		dep = dwc3_wIndex_to_dep(dwc, ctrl->wIndex);
366 		if (!dep)
367 			return -EINVAL;
368 
369 		if (dep->flags & DWC3_EP_STALL)
370 			usb_status = 1 << USB_ENDPOINT_HALT;
371 		break;
372 	default:
373 		return -EINVAL;
374 	};
375 
376 	response_pkt = (__le16 *) dwc->setup_buf;
377 	*response_pkt = cpu_to_le16(usb_status);
378 
379 	dep = dwc->eps[0];
380 	dwc->ep0_usb_req.dep = dep;
381 	dwc->ep0_usb_req.request.length = sizeof(*response_pkt);
382 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
383 	dwc->ep0_usb_req.request.complete = dwc3_ep0_status_cmpl;
384 
385 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
386 }
387 
388 static int dwc3_ep0_handle_feature(struct dwc3 *dwc,
389 		struct usb_ctrlrequest *ctrl, int set)
390 {
391 	struct dwc3_ep		*dep;
392 	u32			recip;
393 	u32			wValue;
394 	u32			wIndex;
395 	u32			reg;
396 	int			ret;
397 
398 	wValue = le16_to_cpu(ctrl->wValue);
399 	wIndex = le16_to_cpu(ctrl->wIndex);
400 	recip = ctrl->bRequestType & USB_RECIP_MASK;
401 	switch (recip) {
402 	case USB_RECIP_DEVICE:
403 
404 		switch (wValue) {
405 		case USB_DEVICE_REMOTE_WAKEUP:
406 			break;
407 		/*
408 		 * 9.4.1 says only only for SS, in AddressState only for
409 		 * default control pipe
410 		 */
411 		case USB_DEVICE_U1_ENABLE:
412 			if (dwc->dev_state != DWC3_CONFIGURED_STATE)
413 				return -EINVAL;
414 			if (dwc->speed != DWC3_DSTS_SUPERSPEED)
415 				return -EINVAL;
416 
417 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
418 			if (set)
419 				reg |= DWC3_DCTL_INITU1ENA;
420 			else
421 				reg &= ~DWC3_DCTL_INITU1ENA;
422 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
423 			break;
424 
425 		case USB_DEVICE_U2_ENABLE:
426 			if (dwc->dev_state != DWC3_CONFIGURED_STATE)
427 				return -EINVAL;
428 			if (dwc->speed != DWC3_DSTS_SUPERSPEED)
429 				return -EINVAL;
430 
431 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
432 			if (set)
433 				reg |= DWC3_DCTL_INITU2ENA;
434 			else
435 				reg &= ~DWC3_DCTL_INITU2ENA;
436 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
437 			break;
438 
439 		case USB_DEVICE_LTM_ENABLE:
440 			return -EINVAL;
441 			break;
442 
443 		case USB_DEVICE_TEST_MODE:
444 			if ((wIndex & 0xff) != 0)
445 				return -EINVAL;
446 			if (!set)
447 				return -EINVAL;
448 
449 			dwc->test_mode_nr = wIndex >> 8;
450 			dwc->test_mode = true;
451 			break;
452 		default:
453 			return -EINVAL;
454 		}
455 		break;
456 
457 	case USB_RECIP_INTERFACE:
458 		switch (wValue) {
459 		case USB_INTRF_FUNC_SUSPEND:
460 			if (wIndex & USB_INTRF_FUNC_SUSPEND_LP)
461 				/* XXX enable Low power suspend */
462 				;
463 			if (wIndex & USB_INTRF_FUNC_SUSPEND_RW)
464 				/* XXX enable remote wakeup */
465 				;
466 			break;
467 		default:
468 			return -EINVAL;
469 		}
470 		break;
471 
472 	case USB_RECIP_ENDPOINT:
473 		switch (wValue) {
474 		case USB_ENDPOINT_HALT:
475 			dep = dwc3_wIndex_to_dep(dwc, wIndex);
476 			if (!dep)
477 				return -EINVAL;
478 			ret = __dwc3_gadget_ep_set_halt(dep, set);
479 			if (ret)
480 				return -EINVAL;
481 			break;
482 		default:
483 			return -EINVAL;
484 		}
485 		break;
486 
487 	default:
488 		return -EINVAL;
489 	};
490 
491 	return 0;
492 }
493 
494 static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
495 {
496 	u32 addr;
497 	u32 reg;
498 
499 	addr = le16_to_cpu(ctrl->wValue);
500 	if (addr > 127) {
501 		dev_dbg(dwc->dev, "invalid device address %d\n", addr);
502 		return -EINVAL;
503 	}
504 
505 	if (dwc->dev_state == DWC3_CONFIGURED_STATE) {
506 		dev_dbg(dwc->dev, "trying to set address when configured\n");
507 		return -EINVAL;
508 	}
509 
510 	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
511 	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
512 	reg |= DWC3_DCFG_DEVADDR(addr);
513 	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
514 
515 	if (addr)
516 		dwc->dev_state = DWC3_ADDRESS_STATE;
517 	else
518 		dwc->dev_state = DWC3_DEFAULT_STATE;
519 
520 	return 0;
521 }
522 
523 static int dwc3_ep0_delegate_req(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
524 {
525 	int ret;
526 
527 	spin_unlock(&dwc->lock);
528 	ret = dwc->gadget_driver->setup(&dwc->gadget, ctrl);
529 	spin_lock(&dwc->lock);
530 	return ret;
531 }
532 
533 static int dwc3_ep0_set_config(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
534 {
535 	u32 cfg;
536 	int ret;
537 	u32 reg;
538 
539 	dwc->start_config_issued = false;
540 	cfg = le16_to_cpu(ctrl->wValue);
541 
542 	switch (dwc->dev_state) {
543 	case DWC3_DEFAULT_STATE:
544 		return -EINVAL;
545 		break;
546 
547 	case DWC3_ADDRESS_STATE:
548 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
549 		/* if the cfg matches and the cfg is non zero */
550 		if (cfg && (!ret || (ret == USB_GADGET_DELAYED_STATUS))) {
551 			dwc->dev_state = DWC3_CONFIGURED_STATE;
552 			/*
553 			 * Enable transition to U1/U2 state when
554 			 * nothing is pending from application.
555 			 */
556 			reg = dwc3_readl(dwc->regs, DWC3_DCTL);
557 			reg |= (DWC3_DCTL_ACCEPTU1ENA | DWC3_DCTL_ACCEPTU2ENA);
558 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
559 
560 			dwc->resize_fifos = true;
561 			dev_dbg(dwc->dev, "resize fifos flag SET\n");
562 		}
563 		break;
564 
565 	case DWC3_CONFIGURED_STATE:
566 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
567 		if (!cfg)
568 			dwc->dev_state = DWC3_ADDRESS_STATE;
569 		break;
570 	default:
571 		ret = -EINVAL;
572 	}
573 	return ret;
574 }
575 
576 static void dwc3_ep0_set_sel_cmpl(struct usb_ep *ep, struct usb_request *req)
577 {
578 	struct dwc3_ep	*dep = to_dwc3_ep(ep);
579 	struct dwc3	*dwc = dep->dwc;
580 
581 	u32		param = 0;
582 	u32		reg;
583 
584 	struct timing {
585 		u8	u1sel;
586 		u8	u1pel;
587 		u16	u2sel;
588 		u16	u2pel;
589 	} __packed timing;
590 
591 	int		ret;
592 
593 	memcpy(&timing, req->buf, sizeof(timing));
594 
595 	dwc->u1sel = timing.u1sel;
596 	dwc->u1pel = timing.u1pel;
597 	dwc->u2sel = le16_to_cpu(timing.u2sel);
598 	dwc->u2pel = le16_to_cpu(timing.u2pel);
599 
600 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
601 	if (reg & DWC3_DCTL_INITU2ENA)
602 		param = dwc->u2pel;
603 	if (reg & DWC3_DCTL_INITU1ENA)
604 		param = dwc->u1pel;
605 
606 	/*
607 	 * According to Synopsys Databook, if parameter is
608 	 * greater than 125, a value of zero should be
609 	 * programmed in the register.
610 	 */
611 	if (param > 125)
612 		param = 0;
613 
614 	/* now that we have the time, issue DGCMD Set Sel */
615 	ret = dwc3_send_gadget_generic_command(dwc,
616 			DWC3_DGCMD_SET_PERIODIC_PAR, param);
617 	WARN_ON(ret < 0);
618 }
619 
620 static int dwc3_ep0_set_sel(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
621 {
622 	struct dwc3_ep	*dep;
623 	u16		wLength;
624 	u16		wValue;
625 
626 	if (dwc->dev_state == DWC3_DEFAULT_STATE)
627 		return -EINVAL;
628 
629 	wValue = le16_to_cpu(ctrl->wValue);
630 	wLength = le16_to_cpu(ctrl->wLength);
631 
632 	if (wLength != 6) {
633 		dev_err(dwc->dev, "Set SEL should be 6 bytes, got %d\n",
634 				wLength);
635 		return -EINVAL;
636 	}
637 
638 	/*
639 	 * To handle Set SEL we need to receive 6 bytes from Host. So let's
640 	 * queue a usb_request for 6 bytes.
641 	 *
642 	 * Remember, though, this controller can't handle non-wMaxPacketSize
643 	 * aligned transfers on the OUT direction, so we queue a request for
644 	 * wMaxPacketSize instead.
645 	 */
646 	dep = dwc->eps[0];
647 	dwc->ep0_usb_req.dep = dep;
648 	dwc->ep0_usb_req.request.length = dep->endpoint.maxpacket;
649 	dwc->ep0_usb_req.request.buf = dwc->setup_buf;
650 	dwc->ep0_usb_req.request.complete = dwc3_ep0_set_sel_cmpl;
651 
652 	return __dwc3_gadget_ep0_queue(dep, &dwc->ep0_usb_req);
653 }
654 
655 static int dwc3_ep0_set_isoch_delay(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
656 {
657 	u16		wLength;
658 	u16		wValue;
659 	u16		wIndex;
660 
661 	wValue = le16_to_cpu(ctrl->wValue);
662 	wLength = le16_to_cpu(ctrl->wLength);
663 	wIndex = le16_to_cpu(ctrl->wIndex);
664 
665 	if (wIndex || wLength)
666 		return -EINVAL;
667 
668 	/*
669 	 * REVISIT It's unclear from Databook what to do with this
670 	 * value. For now, just cache it.
671 	 */
672 	dwc->isoch_delay = wValue;
673 
674 	return 0;
675 }
676 
677 static int dwc3_ep0_std_request(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
678 {
679 	int ret;
680 
681 	switch (ctrl->bRequest) {
682 	case USB_REQ_GET_STATUS:
683 		dev_vdbg(dwc->dev, "USB_REQ_GET_STATUS\n");
684 		ret = dwc3_ep0_handle_status(dwc, ctrl);
685 		break;
686 	case USB_REQ_CLEAR_FEATURE:
687 		dev_vdbg(dwc->dev, "USB_REQ_CLEAR_FEATURE\n");
688 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 0);
689 		break;
690 	case USB_REQ_SET_FEATURE:
691 		dev_vdbg(dwc->dev, "USB_REQ_SET_FEATURE\n");
692 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 1);
693 		break;
694 	case USB_REQ_SET_ADDRESS:
695 		dev_vdbg(dwc->dev, "USB_REQ_SET_ADDRESS\n");
696 		ret = dwc3_ep0_set_address(dwc, ctrl);
697 		break;
698 	case USB_REQ_SET_CONFIGURATION:
699 		dev_vdbg(dwc->dev, "USB_REQ_SET_CONFIGURATION\n");
700 		ret = dwc3_ep0_set_config(dwc, ctrl);
701 		break;
702 	case USB_REQ_SET_SEL:
703 		dev_vdbg(dwc->dev, "USB_REQ_SET_SEL\n");
704 		ret = dwc3_ep0_set_sel(dwc, ctrl);
705 		break;
706 	case USB_REQ_SET_ISOCH_DELAY:
707 		dev_vdbg(dwc->dev, "USB_REQ_SET_ISOCH_DELAY\n");
708 		ret = dwc3_ep0_set_isoch_delay(dwc, ctrl);
709 		break;
710 	default:
711 		dev_vdbg(dwc->dev, "Forwarding to gadget driver\n");
712 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
713 		break;
714 	};
715 
716 	return ret;
717 }
718 
719 static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
720 		const struct dwc3_event_depevt *event)
721 {
722 	struct usb_ctrlrequest *ctrl = dwc->ctrl_req;
723 	int ret = -EINVAL;
724 	u32 len;
725 
726 	if (!dwc->gadget_driver)
727 		goto out;
728 
729 	len = le16_to_cpu(ctrl->wLength);
730 	if (!len) {
731 		dwc->three_stage_setup = false;
732 		dwc->ep0_expect_in = false;
733 		dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
734 	} else {
735 		dwc->three_stage_setup = true;
736 		dwc->ep0_expect_in = !!(ctrl->bRequestType & USB_DIR_IN);
737 		dwc->ep0_next_event = DWC3_EP0_NRDY_DATA;
738 	}
739 
740 	if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
741 		ret = dwc3_ep0_std_request(dwc, ctrl);
742 	else
743 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
744 
745 	if (ret == USB_GADGET_DELAYED_STATUS)
746 		dwc->delayed_status = true;
747 
748 out:
749 	if (ret < 0)
750 		dwc3_ep0_stall_and_restart(dwc);
751 }
752 
753 static void dwc3_ep0_complete_data(struct dwc3 *dwc,
754 		const struct dwc3_event_depevt *event)
755 {
756 	struct dwc3_request	*r = NULL;
757 	struct usb_request	*ur;
758 	struct dwc3_trb		*trb;
759 	struct dwc3_ep		*ep0;
760 	u32			transferred;
761 	u32			status;
762 	u32			length;
763 	u8			epnum;
764 
765 	epnum = event->endpoint_number;
766 	ep0 = dwc->eps[0];
767 
768 	dwc->ep0_next_event = DWC3_EP0_NRDY_STATUS;
769 
770 	r = next_request(&ep0->request_list);
771 	ur = &r->request;
772 
773 	trb = dwc->ep0_trb;
774 
775 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
776 	if (status == DWC3_TRBSTS_SETUP_PENDING) {
777 		dev_dbg(dwc->dev, "Setup Pending received\n");
778 
779 		if (r)
780 			dwc3_gadget_giveback(ep0, r, -ECONNRESET);
781 
782 		return;
783 	}
784 
785 	length = trb->size & DWC3_TRB_SIZE_MASK;
786 
787 	if (dwc->ep0_bounced) {
788 		unsigned transfer_size = ur->length;
789 		unsigned maxp = ep0->endpoint.maxpacket;
790 
791 		transfer_size += (maxp - (transfer_size % maxp));
792 		transferred = min_t(u32, ur->length,
793 				transfer_size - length);
794 		memcpy(ur->buf, dwc->ep0_bounce, transferred);
795 	} else {
796 		transferred = ur->length - length;
797 	}
798 
799 	ur->actual += transferred;
800 
801 	if ((epnum & 1) && ur->actual < ur->length) {
802 		/* for some reason we did not get everything out */
803 
804 		dwc3_ep0_stall_and_restart(dwc);
805 	} else {
806 		/*
807 		 * handle the case where we have to send a zero packet. This
808 		 * seems to be case when req.length > maxpacket. Could it be?
809 		 */
810 		if (r)
811 			dwc3_gadget_giveback(ep0, r, 0);
812 	}
813 }
814 
815 static void dwc3_ep0_complete_status(struct dwc3 *dwc,
816 		const struct dwc3_event_depevt *event)
817 {
818 	struct dwc3_request	*r;
819 	struct dwc3_ep		*dep;
820 	struct dwc3_trb		*trb;
821 	u32			status;
822 
823 	dep = dwc->eps[0];
824 	trb = dwc->ep0_trb;
825 
826 	if (!list_empty(&dep->request_list)) {
827 		r = next_request(&dep->request_list);
828 
829 		dwc3_gadget_giveback(dep, r, 0);
830 	}
831 
832 	if (dwc->test_mode) {
833 		int ret;
834 
835 		ret = dwc3_gadget_set_test_mode(dwc, dwc->test_mode_nr);
836 		if (ret < 0) {
837 			dev_dbg(dwc->dev, "Invalid Test #%d\n",
838 					dwc->test_mode_nr);
839 			dwc3_ep0_stall_and_restart(dwc);
840 			return;
841 		}
842 	}
843 
844 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
845 	if (status == DWC3_TRBSTS_SETUP_PENDING)
846 		dev_dbg(dwc->dev, "Setup Pending received\n");
847 
848 	dwc->ep0state = EP0_SETUP_PHASE;
849 	dwc3_ep0_out_start(dwc);
850 }
851 
852 static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
853 			const struct dwc3_event_depevt *event)
854 {
855 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
856 
857 	dep->flags &= ~DWC3_EP_BUSY;
858 	dep->resource_index = 0;
859 	dwc->setup_packet_pending = false;
860 
861 	switch (dwc->ep0state) {
862 	case EP0_SETUP_PHASE:
863 		dev_vdbg(dwc->dev, "Inspecting Setup Bytes\n");
864 		dwc3_ep0_inspect_setup(dwc, event);
865 		break;
866 
867 	case EP0_DATA_PHASE:
868 		dev_vdbg(dwc->dev, "Data Phase\n");
869 		dwc3_ep0_complete_data(dwc, event);
870 		break;
871 
872 	case EP0_STATUS_PHASE:
873 		dev_vdbg(dwc->dev, "Status Phase\n");
874 		dwc3_ep0_complete_status(dwc, event);
875 		break;
876 	default:
877 		WARN(true, "UNKNOWN ep0state %d\n", dwc->ep0state);
878 	}
879 }
880 
881 static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
882 		struct dwc3_ep *dep, struct dwc3_request *req)
883 {
884 	int			ret;
885 
886 	req->direction = !!dep->number;
887 
888 	if (req->request.length == 0) {
889 		ret = dwc3_ep0_start_trans(dwc, dep->number,
890 				dwc->ctrl_req_addr, 0,
891 				DWC3_TRBCTL_CONTROL_DATA);
892 	} else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
893 			&& (dep->number == 0)) {
894 		u32		transfer_size;
895 
896 		ret = usb_gadget_map_request(&dwc->gadget, &req->request,
897 				dep->number);
898 		if (ret) {
899 			dev_dbg(dwc->dev, "failed to map request\n");
900 			return;
901 		}
902 
903 		WARN_ON(req->request.length > DWC3_EP0_BOUNCE_SIZE);
904 
905 		transfer_size = roundup(req->request.length,
906 				(u32) dep->endpoint.maxpacket);
907 
908 		dwc->ep0_bounced = true;
909 
910 		/*
911 		 * REVISIT in case request length is bigger than
912 		 * DWC3_EP0_BOUNCE_SIZE we will need two chained
913 		 * TRBs to handle the transfer.
914 		 */
915 		ret = dwc3_ep0_start_trans(dwc, dep->number,
916 				dwc->ep0_bounce_addr, transfer_size,
917 				DWC3_TRBCTL_CONTROL_DATA);
918 	} else {
919 		ret = usb_gadget_map_request(&dwc->gadget, &req->request,
920 				dep->number);
921 		if (ret) {
922 			dev_dbg(dwc->dev, "failed to map request\n");
923 			return;
924 		}
925 
926 		ret = dwc3_ep0_start_trans(dwc, dep->number, req->request.dma,
927 				req->request.length, DWC3_TRBCTL_CONTROL_DATA);
928 	}
929 
930 	WARN_ON(ret < 0);
931 }
932 
933 static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
934 {
935 	struct dwc3		*dwc = dep->dwc;
936 	u32			type;
937 
938 	type = dwc->three_stage_setup ? DWC3_TRBCTL_CONTROL_STATUS3
939 		: DWC3_TRBCTL_CONTROL_STATUS2;
940 
941 	return dwc3_ep0_start_trans(dwc, dep->number,
942 			dwc->ctrl_req_addr, 0, type);
943 }
944 
945 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)
946 {
947 	if (dwc->resize_fifos) {
948 		dev_dbg(dwc->dev, "starting to resize fifos\n");
949 		dwc3_gadget_resize_tx_fifos(dwc);
950 		dwc->resize_fifos = 0;
951 	}
952 
953 	WARN_ON(dwc3_ep0_start_control_status(dep));
954 }
955 
956 static void dwc3_ep0_do_control_status(struct dwc3 *dwc,
957 		const struct dwc3_event_depevt *event)
958 {
959 	struct dwc3_ep		*dep = dwc->eps[event->endpoint_number];
960 
961 	__dwc3_ep0_do_control_status(dwc, dep);
962 }
963 
964 static void dwc3_ep0_end_control_data(struct dwc3 *dwc, struct dwc3_ep *dep)
965 {
966 	struct dwc3_gadget_ep_cmd_params params;
967 	u32			cmd;
968 	int			ret;
969 
970 	if (!dep->resource_index)
971 		return;
972 
973 	cmd = DWC3_DEPCMD_ENDTRANSFER;
974 	cmd |= DWC3_DEPCMD_CMDIOC;
975 	cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
976 	memset(&params, 0, sizeof(params));
977 	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
978 	WARN_ON_ONCE(ret);
979 	dep->resource_index = 0;
980 }
981 
982 static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
983 		const struct dwc3_event_depevt *event)
984 {
985 	dwc->setup_packet_pending = true;
986 
987 	switch (event->status) {
988 	case DEPEVT_STATUS_CONTROL_DATA:
989 		dev_vdbg(dwc->dev, "Control Data\n");
990 
991 		/*
992 		 * We already have a DATA transfer in the controller's cache,
993 		 * if we receive a XferNotReady(DATA) we will ignore it, unless
994 		 * it's for the wrong direction.
995 		 *
996 		 * In that case, we must issue END_TRANSFER command to the Data
997 		 * Phase we already have started and issue SetStall on the
998 		 * control endpoint.
999 		 */
1000 		if (dwc->ep0_expect_in != event->endpoint_number) {
1001 			struct dwc3_ep	*dep = dwc->eps[dwc->ep0_expect_in];
1002 
1003 			dev_vdbg(dwc->dev, "Wrong direction for Data phase\n");
1004 			dwc3_ep0_end_control_data(dwc, dep);
1005 			dwc3_ep0_stall_and_restart(dwc);
1006 			return;
1007 		}
1008 
1009 		break;
1010 
1011 	case DEPEVT_STATUS_CONTROL_STATUS:
1012 		if (dwc->ep0_next_event != DWC3_EP0_NRDY_STATUS)
1013 			return;
1014 
1015 		dev_vdbg(dwc->dev, "Control Status\n");
1016 
1017 		dwc->ep0state = EP0_STATUS_PHASE;
1018 
1019 		if (dwc->delayed_status) {
1020 			WARN_ON_ONCE(event->endpoint_number != 1);
1021 			dev_vdbg(dwc->dev, "Mass Storage delayed status\n");
1022 			return;
1023 		}
1024 
1025 		dwc3_ep0_do_control_status(dwc, event);
1026 	}
1027 }
1028 
1029 void dwc3_ep0_interrupt(struct dwc3 *dwc,
1030 		const struct dwc3_event_depevt *event)
1031 {
1032 	u8			epnum = event->endpoint_number;
1033 
1034 	dev_dbg(dwc->dev, "%s while ep%d%s in state '%s'\n",
1035 			dwc3_ep_event_string(event->endpoint_event),
1036 			epnum >> 1, (epnum & 1) ? "in" : "out",
1037 			dwc3_ep0_state_string(dwc->ep0state));
1038 
1039 	switch (event->endpoint_event) {
1040 	case DWC3_DEPEVT_XFERCOMPLETE:
1041 		dwc3_ep0_xfer_complete(dwc, event);
1042 		break;
1043 
1044 	case DWC3_DEPEVT_XFERNOTREADY:
1045 		dwc3_ep0_xfernotready(dwc, event);
1046 		break;
1047 
1048 	case DWC3_DEPEVT_XFERINPROGRESS:
1049 	case DWC3_DEPEVT_RXTXFIFOEVT:
1050 	case DWC3_DEPEVT_STREAMEVT:
1051 	case DWC3_DEPEVT_EPCMDCMPLT:
1052 		break;
1053 	}
1054 }
1055