1// SPDX-License-Identifier: GPL-2.0
2/*
3 * mtu3_gadget.c - MediaTek usb3 DRD peripheral support
4 *
5 * Copyright (C) 2016 MediaTek Inc.
6 *
7 * Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
8 */
9
10#include "mtu3.h"
11
12void mtu3_req_complete(struct mtu3_ep *mep,
13		       struct usb_request *req, int status)
14__releases(mep->mtu->lock)
15__acquires(mep->mtu->lock)
16{
17	struct mtu3_request *mreq = to_mtu3_request(req);
18	struct mtu3 *mtu = mreq->mtu;
19
20	list_del(&mreq->list);
21	if (req->status == -EINPROGRESS)
22		req->status = status;
23
24	spin_unlock(&mtu->lock);
25
26	/* ep0 makes use of PIO, needn't unmap it */
27	if (mep->epnum)
28		usb_gadget_unmap_request(&mtu->g, req, mep->is_in);
29
30	dev_dbg(mtu->dev, "%s complete req: %p, sts %d, %d/%d\n",
31		mep->name, req, req->status, req->actual, req->length);
32
33	usb_gadget_giveback_request(&mep->ep, req);
34	spin_lock(&mtu->lock);
35}
36
37static void nuke(struct mtu3_ep *mep, const int status)
38{
39	struct mtu3_request *mreq = NULL;
40
41	if (list_empty(&mep->req_list))
42		return;
43
44	dev_dbg(mep->mtu->dev, "abort %s's req: sts %d\n", mep->name, status);
45
46	/* exclude EP0 */
47	if (mep->epnum)
48		mtu3_qmu_flush(mep);
49
50	while (!list_empty(&mep->req_list)) {
51		mreq = list_first_entry(&mep->req_list,
52					struct mtu3_request, list);
53		mtu3_req_complete(mep, &mreq->request, status);
54	}
55}
56
57static int mtu3_ep_enable(struct mtu3_ep *mep)
58{
59	const struct usb_endpoint_descriptor *desc;
60	const struct usb_ss_ep_comp_descriptor *comp_desc;
61	struct mtu3 *mtu = mep->mtu;
62	u32 interval = 0;
63	u32 mult = 0;
64	u32 burst = 0;
65	int max_packet;
66	int ret;
67
68	desc = mep->desc;
69	comp_desc = mep->comp_desc;
70	mep->type = usb_endpoint_type(desc);
71	max_packet = usb_endpoint_maxp(desc);
72	mep->maxp = max_packet & GENMASK(10, 0);
73
74	switch (mtu->g.speed) {
75	case USB_SPEED_SUPER:
76	case USB_SPEED_SUPER_PLUS:
77		if (usb_endpoint_xfer_int(desc) ||
78		    usb_endpoint_xfer_isoc(desc)) {
79			interval = desc->bInterval;
80			interval = clamp_val(interval, 1, 16) - 1;
81			if (usb_endpoint_xfer_isoc(desc) && comp_desc)
82				mult = comp_desc->bmAttributes;
83		}
84		if (comp_desc)
85			burst = comp_desc->bMaxBurst;
86
87		break;
88	case USB_SPEED_HIGH:
89		if (usb_endpoint_xfer_isoc(desc) ||
90		    usb_endpoint_xfer_int(desc)) {
91			interval = desc->bInterval;
92			interval = clamp_val(interval, 1, 16) - 1;
93			burst = (max_packet & GENMASK(12, 11)) >> 11;
94		}
95		break;
96	default:
97		break; /*others are ignored */
98	}
99
100	dev_dbg(mtu->dev, "%s maxp:%d, interval:%d, burst:%d, mult:%d\n",
101		__func__, mep->maxp, interval, burst, mult);
102
103	mep->ep.maxpacket = mep->maxp;
104	mep->ep.desc = desc;
105	mep->ep.comp_desc = comp_desc;
106	mep->slot = mtu->slot;
107
108	ret = mtu3_config_ep(mtu, mep, interval, burst, mult);
109	if (ret < 0)
110		return ret;
111
112	ret = mtu3_gpd_ring_alloc(mep);
113	if (ret < 0) {
114		mtu3_deconfig_ep(mtu, mep);
115		return ret;
116	}
117
118	mtu3_qmu_start(mep);
119
120	return 0;
121}
122
123static int mtu3_ep_disable(struct mtu3_ep *mep)
124{
125	struct mtu3 *mtu = mep->mtu;
126
127	mtu3_qmu_stop(mep);
128
129	/* abort all pending requests */
130	nuke(mep, -ESHUTDOWN);
131	mtu3_deconfig_ep(mtu, mep);
132	mtu3_gpd_ring_free(mep);
133
134	mep->desc = NULL;
135	mep->ep.desc = NULL;
136	mep->comp_desc = NULL;
137	mep->type = 0;
138	mep->flags = 0;
139
140	return 0;
141}
142
143static int mtu3_gadget_ep_enable(struct usb_ep *ep,
144				 const struct usb_endpoint_descriptor *desc)
145{
146	struct mtu3_ep *mep;
147	struct mtu3 *mtu;
148	unsigned long flags;
149	int ret = -EINVAL;
150
151	if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
152		pr_debug("%s invalid parameters\n", __func__);
153		return -EINVAL;
154	}
155
156	if (!desc->wMaxPacketSize) {
157		pr_debug("%s missing wMaxPacketSize\n", __func__);
158		return -EINVAL;
159	}
160	mep = to_mtu3_ep(ep);
161	mtu = mep->mtu;
162
163	/* check ep number and direction against endpoint */
164	if (usb_endpoint_num(desc) != mep->epnum)
165		return -EINVAL;
166
167	if (!!usb_endpoint_dir_in(desc) ^ !!mep->is_in)
168		return -EINVAL;
169
170	dev_dbg(mtu->dev, "%s %s\n", __func__, ep->name);
171
172	if (mep->flags & MTU3_EP_ENABLED) {
173		dev_warn(mtu->dev, "%s is already enabled\n", mep->name);
174		return 0;
175	}
176
177	spin_lock_irqsave(&mtu->lock, flags);
178	mep->desc = desc;
179	mep->comp_desc = ep->comp_desc;
180
181	ret = mtu3_ep_enable(mep);
182	if (ret)
183		goto error;
184
185	mep->flags = MTU3_EP_ENABLED;
186	mtu->active_ep++;
187
188error:
189	spin_unlock_irqrestore(&mtu->lock, flags);
190
191	dev_dbg(mtu->dev, "%s active_ep=%d\n", __func__, mtu->active_ep);
192
193	return ret;
194}
195
196static int mtu3_gadget_ep_disable(struct usb_ep *ep)
197{
198	struct mtu3_ep *mep = to_mtu3_ep(ep);
199	struct mtu3 *mtu = mep->mtu;
200	unsigned long flags;
201
202	dev_dbg(mtu->dev, "%s %s\n", __func__, mep->name);
203
204	if (!(mep->flags & MTU3_EP_ENABLED)) {
205		dev_warn(mtu->dev, "%s is already disabled\n", mep->name);
206		return 0;
207	}
208
209	spin_lock_irqsave(&mtu->lock, flags);
210	mtu3_ep_disable(mep);
211	mep->flags = 0;
212	mtu->active_ep--;
213	spin_unlock_irqrestore(&mtu->lock, flags);
214
215	dev_dbg(mtu->dev, "%s active_ep=%d, mtu3 is_active=%d\n",
216		__func__, mtu->active_ep, mtu->is_active);
217
218	return 0;
219}
220
221struct usb_request *mtu3_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
222{
223	struct mtu3_ep *mep = to_mtu3_ep(ep);
224	struct mtu3_request *mreq;
225
226	mreq = kzalloc(sizeof(*mreq), gfp_flags);
227	if (!mreq)
228		return NULL;
229
230	mreq->request.dma = DMA_ADDR_INVALID;
231	mreq->epnum = mep->epnum;
232	mreq->mep = mep;
233
234	return &mreq->request;
235}
236
237void mtu3_free_request(struct usb_ep *ep, struct usb_request *req)
238{
239	struct mtu3_request *mreq = to_mtu3_request(req);
240
241	kfree(mreq);
242}
243
244static int mtu3_gadget_queue(struct usb_ep *ep,
245			     struct usb_request *req, gfp_t gfp_flags)
246{
247	struct mtu3_ep *mep = to_mtu3_ep(ep);
248	struct mtu3_request *mreq = to_mtu3_request(req);
249	struct mtu3 *mtu = mep->mtu;
250	unsigned long flags;
251	int ret = 0;
252
253	if (!req->buf)
254		return -ENODATA;
255
256	if (mreq->mep != mep)
257		return -EINVAL;
258
259	dev_dbg(mtu->dev, "%s %s EP%d(%s), req=%p, maxp=%d, len#%d\n",
260		__func__, mep->is_in ? "TX" : "RX", mreq->epnum, ep->name,
261		mreq, ep->maxpacket, mreq->request.length);
262
263	if (req->length > GPD_BUF_SIZE) {
264		dev_warn(mtu->dev,
265			 "req length > supported MAX:%d requested:%d\n",
266			 GPD_BUF_SIZE, req->length);
267		return -EOPNOTSUPP;
268	}
269
270	/* don't queue if the ep is down */
271	if (!mep->desc) {
272		dev_dbg(mtu->dev, "req=%p queued to %s while it's disabled\n",
273			req, ep->name);
274		return -ESHUTDOWN;
275	}
276
277	mreq->mtu = mtu;
278	mreq->request.actual = 0;
279	mreq->request.status = -EINPROGRESS;
280
281	ret = usb_gadget_map_request(&mtu->g, req, mep->is_in);
282	if (ret) {
283		dev_err(mtu->dev, "dma mapping failed\n");
284		return ret;
285	}
286
287	spin_lock_irqsave(&mtu->lock, flags);
288
289	if (mtu3_prepare_transfer(mep)) {
290		ret = -EAGAIN;
291		goto error;
292	}
293
294	list_add_tail(&mreq->list, &mep->req_list);
295	mtu3_insert_gpd(mep, mreq);
296	mtu3_qmu_resume(mep);
297
298error:
299	spin_unlock_irqrestore(&mtu->lock, flags);
300
301	return ret;
302}
303
304static int mtu3_gadget_dequeue(struct usb_ep *ep, struct usb_request *req)
305{
306	struct mtu3_ep *mep = to_mtu3_ep(ep);
307	struct mtu3_request *mreq = to_mtu3_request(req);
308	struct mtu3_request *r;
309	struct mtu3 *mtu = mep->mtu;
310	unsigned long flags;
311	int ret = 0;
312
313	if (mreq->mep != mep)
314		return -EINVAL;
315
316	dev_dbg(mtu->dev, "%s : req=%p\n", __func__, req);
317
318	spin_lock_irqsave(&mtu->lock, flags);
319
320	list_for_each_entry(r, &mep->req_list, list) {
321		if (r == mreq)
322			break;
323	}
324	if (r != mreq) {
325		dev_dbg(mtu->dev, "req=%p not queued to %s\n", req, ep->name);
326		ret = -EINVAL;
327		goto done;
328	}
329
330	mtu3_qmu_flush(mep);  /* REVISIT: set BPS ?? */
331	mtu3_req_complete(mep, req, -ECONNRESET);
332	mtu3_qmu_start(mep);
333
334done:
335	spin_unlock_irqrestore(&mtu->lock, flags);
336
337	return ret;
338}
339
340/*
341 * Set or clear the halt bit of an EP.
342 * A halted EP won't TX/RX any data but will queue requests.
343 */
344static int mtu3_gadget_ep_set_halt(struct usb_ep *ep, int value)
345{
346	struct mtu3_ep *mep = to_mtu3_ep(ep);
347	struct mtu3 *mtu = mep->mtu;
348	struct mtu3_request *mreq;
349	unsigned long flags = 0;
350	int ret = 0;
351
352	dev_dbg(mtu->dev, "%s : %s...", __func__, ep->name);
353
354	spin_lock_irqsave(&mtu->lock, flags);
355
356	if (mep->type == USB_ENDPOINT_XFER_ISOC) {
357		ret = -EINVAL;
358		goto done;
359	}
360
361	mreq = next_request(mep);
362	if (value) {
363		/*
364		 * If there is not request for TX-EP, QMU will not transfer
365		 * data to TX-FIFO, so no need check whether TX-FIFO
366		 * holds bytes or not here
367		 */
368		if (mreq) {
369			dev_dbg(mtu->dev, "req in progress, cannot halt %s\n",
370				ep->name);
371			ret = -EAGAIN;
372			goto done;
373		}
374	} else {
375		mep->flags &= ~MTU3_EP_WEDGE;
376	}
377
378	dev_dbg(mtu->dev, "%s %s stall\n", ep->name, value ? "set" : "clear");
379
380	mtu3_ep_stall_set(mep, value);
381
382done:
383	spin_unlock_irqrestore(&mtu->lock, flags);
384
385	return ret;
386}
387
388/* Sets the halt feature with the clear requests ignored */
389static int mtu3_gadget_ep_set_wedge(struct usb_ep *ep)
390{
391	struct mtu3_ep *mep = to_mtu3_ep(ep);
392
393	mep->flags |= MTU3_EP_WEDGE;
394
395	return usb_ep_set_halt(ep);
396}
397
398static const struct usb_ep_ops mtu3_ep_ops = {
399	.enable = mtu3_gadget_ep_enable,
400	.disable = mtu3_gadget_ep_disable,
401	.alloc_request = mtu3_alloc_request,
402	.free_request = mtu3_free_request,
403	.queue = mtu3_gadget_queue,
404	.dequeue = mtu3_gadget_dequeue,
405	.set_halt = mtu3_gadget_ep_set_halt,
406	.set_wedge = mtu3_gadget_ep_set_wedge,
407};
408
409static int mtu3_gadget_get_frame(struct usb_gadget *gadget)
410{
411	struct mtu3 *mtu = gadget_to_mtu3(gadget);
412
413	return (int)mtu3_readl(mtu->mac_base, U3D_USB20_FRAME_NUM);
414}
415
416static int mtu3_gadget_wakeup(struct usb_gadget *gadget)
417{
418	struct mtu3 *mtu = gadget_to_mtu3(gadget);
419	unsigned long flags;
420
421	dev_dbg(mtu->dev, "%s\n", __func__);
422
423	/* remote wakeup feature is not enabled by host */
424	if (!mtu->may_wakeup)
425		return  -EOPNOTSUPP;
426
427	spin_lock_irqsave(&mtu->lock, flags);
428	if (mtu->g.speed >= USB_SPEED_SUPER) {
429		mtu3_setbits(mtu->mac_base, U3D_LINK_POWER_CONTROL, UX_EXIT);
430	} else {
431		mtu3_setbits(mtu->mac_base, U3D_POWER_MANAGEMENT, RESUME);
432		spin_unlock_irqrestore(&mtu->lock, flags);
433		mdelay(10);
434		spin_lock_irqsave(&mtu->lock, flags);
435		mtu3_clrbits(mtu->mac_base, U3D_POWER_MANAGEMENT, RESUME);
436	}
437	spin_unlock_irqrestore(&mtu->lock, flags);
438	return 0;
439}
440
441static int mtu3_gadget_set_self_powered(struct usb_gadget *gadget,
442					int is_selfpowered)
443{
444	struct mtu3 *mtu = gadget_to_mtu3(gadget);
445
446	mtu->is_self_powered = !!is_selfpowered;
447	return 0;
448}
449
450static int mtu3_gadget_pullup(struct usb_gadget *gadget, int is_on)
451{
452	struct mtu3 *mtu = gadget_to_mtu3(gadget);
453	unsigned long flags;
454
455	dev_dbg(mtu->dev, "%s (%s) for %sactive device\n", __func__,
456		is_on ? "on" : "off", mtu->is_active ? "" : "in");
457
458	/* we'd rather not pullup unless the device is active. */
459	spin_lock_irqsave(&mtu->lock, flags);
460
461	is_on = !!is_on;
462	if (!mtu->is_active) {
463		/* save it for mtu3_start() to process the request */
464		mtu->softconnect = is_on;
465	} else if (is_on != mtu->softconnect) {
466		mtu->softconnect = is_on;
467		mtu3_dev_on_off(mtu, is_on);
468	}
469
470	spin_unlock_irqrestore(&mtu->lock, flags);
471
472	return 0;
473}
474
475static int mtu3_gadget_start(struct usb_gadget *gadget,
476			     struct usb_gadget_driver *driver)
477{
478	struct mtu3 *mtu = gadget_to_mtu3(gadget);
479	unsigned long flags;
480
481	if (mtu->gadget_driver) {
482		dev_err(mtu->dev, "%s is already bound to %s\n",
483			mtu->g.name, mtu->gadget_driver->function);
484		return -EBUSY;
485	}
486
487	dev_dbg(mtu->dev, "bind driver %s\n", driver->function);
488
489	spin_lock_irqsave(&mtu->lock, flags);
490
491	mtu->softconnect = 0;
492	mtu->gadget_driver = driver;
493	mtu3_start(mtu);
494
495	spin_unlock_irqrestore(&mtu->lock, flags);
496
497	return 0;
498}
499
500static void stop_activity(struct mtu3 *mtu)
501{
502	int i;
503
504	mtu->g.speed = USB_SPEED_UNKNOWN;
505
506	/* deactivate the hardware */
507	if (mtu->softconnect) {
508		mtu->softconnect = 0;
509		mtu3_dev_on_off(mtu, 0);
510	}
511
512	/*
513	 * killing any outstanding requests will quiesce the driver;
514	 * then report disconnect
515	 */
516	nuke(mtu->ep0, -ESHUTDOWN);
517	for (i = 1; i < mtu->num_eps; i++) {
518		nuke(mtu->in_eps + i, -ESHUTDOWN);
519		nuke(mtu->out_eps + i, -ESHUTDOWN);
520	}
521}
522
523static int mtu3_gadget_stop(struct usb_gadget *g)
524{
525	struct mtu3 *mtu = gadget_to_mtu3(g);
526	unsigned long flags;
527
528	dev_dbg(mtu->dev, "%s\n", __func__);
529
530	spin_lock_irqsave(&mtu->lock, flags);
531
532	stop_activity(mtu);
533	mtu->gadget_driver = NULL;
534	mtu3_stop(mtu);
535
536	spin_unlock_irqrestore(&mtu->lock, flags);
537
538	return 0;
539}
540
541static void
542mtu3_gadget_set_speed(struct usb_gadget *g, enum usb_device_speed speed)
543{
544	struct mtu3 *mtu = gadget_to_mtu3(g);
545	unsigned long flags;
546
547	dev_dbg(mtu->dev, "%s %d\n", __func__, speed);
548
549	spin_lock_irqsave(&mtu->lock, flags);
550	mtu3_set_speed(mtu, speed);
551	spin_unlock_irqrestore(&mtu->lock, flags);
552}
553
554static const struct usb_gadget_ops mtu3_gadget_ops = {
555	.get_frame = mtu3_gadget_get_frame,
556	.wakeup = mtu3_gadget_wakeup,
557	.set_selfpowered = mtu3_gadget_set_self_powered,
558	.pullup = mtu3_gadget_pullup,
559	.udc_start = mtu3_gadget_start,
560	.udc_stop = mtu3_gadget_stop,
561	.udc_set_speed = mtu3_gadget_set_speed,
562};
563
564static void mtu3_state_reset(struct mtu3 *mtu)
565{
566	mtu->address = 0;
567	mtu->ep0_state = MU3D_EP0_STATE_SETUP;
568	mtu->may_wakeup = 0;
569	mtu->u1_enable = 0;
570	mtu->u2_enable = 0;
571	mtu->delayed_status = false;
572	mtu->test_mode = false;
573}
574
575static void init_hw_ep(struct mtu3 *mtu, struct mtu3_ep *mep,
576		       u32 epnum, u32 is_in)
577{
578	mep->epnum = epnum;
579	mep->mtu = mtu;
580	mep->is_in = is_in;
581
582	INIT_LIST_HEAD(&mep->req_list);
583
584	sprintf(mep->name, "ep%d%s", epnum,
585		!epnum ? "" : (is_in ? "in" : "out"));
586
587	mep->ep.name = mep->name;
588	INIT_LIST_HEAD(&mep->ep.ep_list);
589
590	/* initialize maxpacket as SS */
591	if (!epnum) {
592		usb_ep_set_maxpacket_limit(&mep->ep, USB_HS_MAXP);
593		mep->ep.ops = &mtu3_ep0_ops;
594		mtu->g.ep0 = &mep->ep;
595	} else {
596		usb_ep_set_maxpacket_limit(&mep->ep, USB_SS_MAXP);
597		mep->ep.ops = &mtu3_ep_ops;
598		list_add_tail(&mep->ep.ep_list, &mtu->g.ep_list);
599	}
600
601	dev_dbg(mtu->dev, "%s, name=%s, maxp=%d\n", __func__, mep->ep.name,
602		mep->ep.maxpacket);
603}
604
605static void mtu3_gadget_init_eps(struct mtu3 *mtu)
606{
607	u8 epnum;
608
609	/* initialize endpoint list just once */
610	INIT_LIST_HEAD(&mtu->g.ep_list);
611
612	dev_dbg(mtu->dev, "%s num_eps(1 for a pair of tx&rx ep)=%d\n",
613		__func__, mtu->num_eps);
614
615	init_hw_ep(mtu, mtu->ep0, 0, 0);
616	for (epnum = 1; epnum < mtu->num_eps; epnum++) {
617		init_hw_ep(mtu, mtu->in_eps + epnum, epnum, 1);
618		init_hw_ep(mtu, mtu->out_eps + epnum, epnum, 0);
619	}
620}
621
622int mtu3_gadget_setup(struct mtu3 *mtu)
623{
624	mtu->g.ops = &mtu3_gadget_ops;
625	mtu->g.max_speed = mtu->max_speed;
626	mtu->g.speed = USB_SPEED_UNKNOWN;
627	mtu->g.is_dualspeed = 1;
628	mtu->g.name = MTU3_DRIVER_NAME;
629	mtu->is_active = 0;
630	mtu->delayed_status = false;
631
632	mtu3_gadget_init_eps(mtu);
633
634	return usb_add_gadget_udc((struct device *)mtu->dev, &mtu->g);
635}
636
637void mtu3_gadget_cleanup(struct mtu3 *mtu)
638{
639	usb_del_gadget_udc(&mtu->g);
640}
641
642void mtu3_gadget_resume(struct mtu3 *mtu)
643{
644	dev_dbg(mtu->dev, "gadget RESUME\n");
645	if (mtu->gadget_driver && mtu->gadget_driver->resume) {
646		spin_unlock(&mtu->lock);
647		mtu->gadget_driver->resume(&mtu->g);
648		spin_lock(&mtu->lock);
649	}
650}
651
652/* called when SOF packets stop for 3+ msec or enters U3 */
653void mtu3_gadget_suspend(struct mtu3 *mtu)
654{
655	dev_dbg(mtu->dev, "gadget SUSPEND\n");
656	if (mtu->gadget_driver && mtu->gadget_driver->suspend) {
657		spin_unlock(&mtu->lock);
658		mtu->gadget_driver->suspend(&mtu->g);
659		spin_lock(&mtu->lock);
660	}
661}
662
663/* called when VBUS drops below session threshold, and in other cases */
664void mtu3_gadget_disconnect(struct mtu3 *mtu)
665{
666	dev_dbg(mtu->dev, "gadget DISCONNECT\n");
667	if (mtu->gadget_driver && mtu->gadget_driver->disconnect) {
668		spin_unlock(&mtu->lock);
669		mtu->gadget_driver->disconnect(&mtu->g);
670		spin_lock(&mtu->lock);
671	}
672
673	mtu3_state_reset(mtu);
674	usb_gadget_set_state(&mtu->g, USB_STATE_NOTATTACHED);
675}
676
677void mtu3_gadget_reset(struct mtu3 *mtu)
678{
679	dev_dbg(mtu->dev, "gadget RESET\n");
680
681	/* report disconnect, if we didn't flush EP state */
682	if (mtu->g.speed != USB_SPEED_UNKNOWN)
683		mtu3_gadget_disconnect(mtu);
684	else
685		mtu3_state_reset(mtu);
686}
687