gadget.c revision c6f83f386c2f7987a344368e33e55840c12bd38f
1/**
2 * gadget.c - DesignWare USB3 DRD Controller Gadget Framework Link
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/delay.h>
41#include <linux/slab.h>
42#include <linux/spinlock.h>
43#include <linux/platform_device.h>
44#include <linux/pm_runtime.h>
45#include <linux/interrupt.h>
46#include <linux/io.h>
47#include <linux/list.h>
48#include <linux/dma-mapping.h>
49
50#include <linux/usb/ch9.h>
51#include <linux/usb/gadget.h>
52
53#include "core.h"
54#include "gadget.h"
55#include "io.h"
56
57/**
58 * dwc3_gadget_set_test_mode - Enables USB2 Test Modes
59 * @dwc: pointer to our context structure
60 * @mode: the mode to set (J, K SE0 NAK, Force Enable)
61 *
62 * Caller should take care of locking. This function will
63 * return 0 on success or -EINVAL if wrong Test Selector
64 * is passed
65 */
66int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode)
67{
68	u32		reg;
69
70	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
71	reg &= ~DWC3_DCTL_TSTCTRL_MASK;
72
73	switch (mode) {
74	case TEST_J:
75	case TEST_K:
76	case TEST_SE0_NAK:
77	case TEST_PACKET:
78	case TEST_FORCE_EN:
79		reg |= mode << 1;
80		break;
81	default:
82		return -EINVAL;
83	}
84
85	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
86
87	return 0;
88}
89
90/**
91 * dwc3_gadget_set_link_state - Sets USB Link to a particular State
92 * @dwc: pointer to our context structure
93 * @state: the state to put link into
94 *
95 * Caller should take care of locking. This function will
96 * return 0 on success or -ETIMEDOUT.
97 */
98int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
99{
100	int		retries = 10000;
101	u32		reg;
102
103	/*
104	 * Wait until device controller is ready. Only applies to 1.94a and
105	 * later RTL.
106	 */
107	if (dwc->revision >= DWC3_REVISION_194A) {
108		while (--retries) {
109			reg = dwc3_readl(dwc->regs, DWC3_DSTS);
110			if (reg & DWC3_DSTS_DCNRD)
111				udelay(5);
112			else
113				break;
114		}
115
116		if (retries <= 0)
117			return -ETIMEDOUT;
118	}
119
120	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
121	reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
122
123	/* set requested state */
124	reg |= DWC3_DCTL_ULSTCHNGREQ(state);
125	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
126
127	/*
128	 * The following code is racy when called from dwc3_gadget_wakeup,
129	 * and is not needed, at least on newer versions
130	 */
131	if (dwc->revision >= DWC3_REVISION_194A)
132		return 0;
133
134	/* wait for a change in DSTS */
135	retries = 10000;
136	while (--retries) {
137		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
138
139		if (DWC3_DSTS_USBLNKST(reg) == state)
140			return 0;
141
142		udelay(5);
143	}
144
145	dev_vdbg(dwc->dev, "link state change request timed out\n");
146
147	return -ETIMEDOUT;
148}
149
150/**
151 * dwc3_gadget_resize_tx_fifos - reallocate fifo spaces for current use-case
152 * @dwc: pointer to our context structure
153 *
154 * This function will a best effort FIFO allocation in order
155 * to improve FIFO usage and throughput, while still allowing
156 * us to enable as many endpoints as possible.
157 *
158 * Keep in mind that this operation will be highly dependent
159 * on the configured size for RAM1 - which contains TxFifo -,
160 * the amount of endpoints enabled on coreConsultant tool, and
161 * the width of the Master Bus.
162 *
163 * In the ideal world, we would always be able to satisfy the
164 * following equation:
165 *
166 * ((512 + 2 * MDWIDTH-Bytes) + (Number of IN Endpoints - 1) * \
167 * (3 * (1024 + MDWIDTH-Bytes) + MDWIDTH-Bytes)) / MDWIDTH-Bytes
168 *
169 * Unfortunately, due to many variables that's not always the case.
170 */
171int dwc3_gadget_resize_tx_fifos(struct dwc3 *dwc)
172{
173	int		last_fifo_depth = 0;
174	int		ram1_depth;
175	int		fifo_size;
176	int		mdwidth;
177	int		num;
178
179	if (!dwc->needs_fifo_resize)
180		return 0;
181
182	ram1_depth = DWC3_RAM1_DEPTH(dwc->hwparams.hwparams7);
183	mdwidth = DWC3_MDWIDTH(dwc->hwparams.hwparams0);
184
185	/* MDWIDTH is represented in bits, we need it in bytes */
186	mdwidth >>= 3;
187
188	/*
189	 * FIXME For now we will only allocate 1 wMaxPacketSize space
190	 * for each enabled endpoint, later patches will come to
191	 * improve this algorithm so that we better use the internal
192	 * FIFO space
193	 */
194	for (num = 0; num < DWC3_ENDPOINTS_NUM; num++) {
195		struct dwc3_ep	*dep = dwc->eps[num];
196		int		fifo_number = dep->number >> 1;
197		int		mult = 1;
198		int		tmp;
199
200		if (!(dep->number & 1))
201			continue;
202
203		if (!(dep->flags & DWC3_EP_ENABLED))
204			continue;
205
206		if (usb_endpoint_xfer_bulk(dep->endpoint.desc)
207				|| usb_endpoint_xfer_isoc(dep->endpoint.desc))
208			mult = 3;
209
210		/*
211		 * REVISIT: the following assumes we will always have enough
212		 * space available on the FIFO RAM for all possible use cases.
213		 * Make sure that's true somehow and change FIFO allocation
214		 * accordingly.
215		 *
216		 * If we have Bulk or Isochronous endpoints, we want
217		 * them to be able to be very, very fast. So we're giving
218		 * those endpoints a fifo_size which is enough for 3 full
219		 * packets
220		 */
221		tmp = mult * (dep->endpoint.maxpacket + mdwidth);
222		tmp += mdwidth;
223
224		fifo_size = DIV_ROUND_UP(tmp, mdwidth);
225
226		fifo_size |= (last_fifo_depth << 16);
227
228		dev_vdbg(dwc->dev, "%s: Fifo Addr %04x Size %d\n",
229				dep->name, last_fifo_depth, fifo_size & 0xffff);
230
231		dwc3_writel(dwc->regs, DWC3_GTXFIFOSIZ(fifo_number),
232				fifo_size);
233
234		last_fifo_depth += (fifo_size & 0xffff);
235	}
236
237	return 0;
238}
239
240void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
241		int status)
242{
243	struct dwc3			*dwc = dep->dwc;
244
245	if (req->queued) {
246		if (req->request.num_mapped_sgs)
247			dep->busy_slot += req->request.num_mapped_sgs;
248		else
249			dep->busy_slot++;
250
251		/*
252		 * Skip LINK TRB. We can't use req->trb and check for
253		 * DWC3_TRBCTL_LINK_TRB because it points the TRB we just
254		 * completed (not the LINK TRB).
255		 */
256		if (((dep->busy_slot & DWC3_TRB_MASK) == DWC3_TRB_NUM - 1) &&
257				usb_endpoint_xfer_isoc(dep->endpoint.desc))
258			dep->busy_slot++;
259	}
260	list_del(&req->list);
261	req->trb = NULL;
262
263	if (req->request.status == -EINPROGRESS)
264		req->request.status = status;
265
266	usb_gadget_unmap_request(&dwc->gadget, &req->request,
267			req->direction);
268
269	dev_dbg(dwc->dev, "request %p from %s completed %d/%d ===> %d\n",
270			req, dep->name, req->request.actual,
271			req->request.length, status);
272
273	spin_unlock(&dwc->lock);
274	req->request.complete(&dep->endpoint, &req->request);
275	spin_lock(&dwc->lock);
276}
277
278static const char *dwc3_gadget_ep_cmd_string(u8 cmd)
279{
280	switch (cmd) {
281	case DWC3_DEPCMD_DEPSTARTCFG:
282		return "Start New Configuration";
283	case DWC3_DEPCMD_ENDTRANSFER:
284		return "End Transfer";
285	case DWC3_DEPCMD_UPDATETRANSFER:
286		return "Update Transfer";
287	case DWC3_DEPCMD_STARTTRANSFER:
288		return "Start Transfer";
289	case DWC3_DEPCMD_CLEARSTALL:
290		return "Clear Stall";
291	case DWC3_DEPCMD_SETSTALL:
292		return "Set Stall";
293	case DWC3_DEPCMD_GETEPSTATE:
294		return "Get Endpoint State";
295	case DWC3_DEPCMD_SETTRANSFRESOURCE:
296		return "Set Endpoint Transfer Resource";
297	case DWC3_DEPCMD_SETEPCONFIG:
298		return "Set Endpoint Configuration";
299	default:
300		return "UNKNOWN command";
301	}
302}
303
304int dwc3_send_gadget_generic_command(struct dwc3 *dwc, int cmd, u32 param)
305{
306	u32		timeout = 500;
307	u32		reg;
308
309	dwc3_writel(dwc->regs, DWC3_DGCMDPAR, param);
310	dwc3_writel(dwc->regs, DWC3_DGCMD, cmd | DWC3_DGCMD_CMDACT);
311
312	do {
313		reg = dwc3_readl(dwc->regs, DWC3_DGCMD);
314		if (!(reg & DWC3_DGCMD_CMDACT)) {
315			dev_vdbg(dwc->dev, "Command Complete --> %d\n",
316					DWC3_DGCMD_STATUS(reg));
317			return 0;
318		}
319
320		/*
321		 * We can't sleep here, because it's also called from
322		 * interrupt context.
323		 */
324		timeout--;
325		if (!timeout)
326			return -ETIMEDOUT;
327		udelay(1);
328	} while (1);
329}
330
331int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
332		unsigned cmd, struct dwc3_gadget_ep_cmd_params *params)
333{
334	struct dwc3_ep		*dep = dwc->eps[ep];
335	u32			timeout = 500;
336	u32			reg;
337
338	dev_vdbg(dwc->dev, "%s: cmd '%s' params %08x %08x %08x\n",
339			dep->name,
340			dwc3_gadget_ep_cmd_string(cmd), params->param0,
341			params->param1, params->param2);
342
343	dwc3_writel(dwc->regs, DWC3_DEPCMDPAR0(ep), params->param0);
344	dwc3_writel(dwc->regs, DWC3_DEPCMDPAR1(ep), params->param1);
345	dwc3_writel(dwc->regs, DWC3_DEPCMDPAR2(ep), params->param2);
346
347	dwc3_writel(dwc->regs, DWC3_DEPCMD(ep), cmd | DWC3_DEPCMD_CMDACT);
348	do {
349		reg = dwc3_readl(dwc->regs, DWC3_DEPCMD(ep));
350		if (!(reg & DWC3_DEPCMD_CMDACT)) {
351			dev_vdbg(dwc->dev, "Command Complete --> %d\n",
352					DWC3_DEPCMD_STATUS(reg));
353			return 0;
354		}
355
356		/*
357		 * We can't sleep here, because it is also called from
358		 * interrupt context.
359		 */
360		timeout--;
361		if (!timeout)
362			return -ETIMEDOUT;
363
364		udelay(1);
365	} while (1);
366}
367
368static dma_addr_t dwc3_trb_dma_offset(struct dwc3_ep *dep,
369		struct dwc3_trb *trb)
370{
371	u32		offset = (char *) trb - (char *) dep->trb_pool;
372
373	return dep->trb_pool_dma + offset;
374}
375
376static int dwc3_alloc_trb_pool(struct dwc3_ep *dep)
377{
378	struct dwc3		*dwc = dep->dwc;
379
380	if (dep->trb_pool)
381		return 0;
382
383	if (dep->number == 0 || dep->number == 1)
384		return 0;
385
386	dep->trb_pool = dma_alloc_coherent(dwc->dev,
387			sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
388			&dep->trb_pool_dma, GFP_KERNEL);
389	if (!dep->trb_pool) {
390		dev_err(dep->dwc->dev, "failed to allocate trb pool for %s\n",
391				dep->name);
392		return -ENOMEM;
393	}
394
395	return 0;
396}
397
398static void dwc3_free_trb_pool(struct dwc3_ep *dep)
399{
400	struct dwc3		*dwc = dep->dwc;
401
402	dma_free_coherent(dwc->dev, sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
403			dep->trb_pool, dep->trb_pool_dma);
404
405	dep->trb_pool = NULL;
406	dep->trb_pool_dma = 0;
407}
408
409static int dwc3_gadget_start_config(struct dwc3 *dwc, struct dwc3_ep *dep)
410{
411	struct dwc3_gadget_ep_cmd_params params;
412	u32			cmd;
413
414	memset(&params, 0x00, sizeof(params));
415
416	if (dep->number != 1) {
417		cmd = DWC3_DEPCMD_DEPSTARTCFG;
418		/* XferRscIdx == 0 for ep0 and 2 for the remaining */
419		if (dep->number > 1) {
420			if (dwc->start_config_issued)
421				return 0;
422			dwc->start_config_issued = true;
423			cmd |= DWC3_DEPCMD_PARAM(2);
424		}
425
426		return dwc3_send_gadget_ep_cmd(dwc, 0, cmd, &params);
427	}
428
429	return 0;
430}
431
432static int dwc3_gadget_set_ep_config(struct dwc3 *dwc, struct dwc3_ep *dep,
433		const struct usb_endpoint_descriptor *desc,
434		const struct usb_ss_ep_comp_descriptor *comp_desc,
435		bool ignore)
436{
437	struct dwc3_gadget_ep_cmd_params params;
438
439	memset(&params, 0x00, sizeof(params));
440
441	params.param0 = DWC3_DEPCFG_EP_TYPE(usb_endpoint_type(desc))
442		| DWC3_DEPCFG_MAX_PACKET_SIZE(usb_endpoint_maxp(desc))
443		| DWC3_DEPCFG_BURST_SIZE(dep->endpoint.maxburst - 1);
444
445	if (ignore)
446		params.param0 |= DWC3_DEPCFG_IGN_SEQ_NUM;
447
448	params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN
449		| DWC3_DEPCFG_XFER_NOT_READY_EN;
450
451	if (usb_ss_max_streams(comp_desc) && usb_endpoint_xfer_bulk(desc)) {
452		params.param1 |= DWC3_DEPCFG_STREAM_CAPABLE
453			| DWC3_DEPCFG_STREAM_EVENT_EN;
454		dep->stream_capable = true;
455	}
456
457	if (usb_endpoint_xfer_isoc(desc))
458		params.param1 |= DWC3_DEPCFG_XFER_IN_PROGRESS_EN;
459
460	/*
461	 * We are doing 1:1 mapping for endpoints, meaning
462	 * Physical Endpoints 2 maps to Logical Endpoint 2 and
463	 * so on. We consider the direction bit as part of the physical
464	 * endpoint number. So USB endpoint 0x81 is 0x03.
465	 */
466	params.param1 |= DWC3_DEPCFG_EP_NUMBER(dep->number);
467
468	/*
469	 * We must use the lower 16 TX FIFOs even though
470	 * HW might have more
471	 */
472	if (dep->direction)
473		params.param0 |= DWC3_DEPCFG_FIFO_NUMBER(dep->number >> 1);
474
475	if (desc->bInterval) {
476		params.param1 |= DWC3_DEPCFG_BINTERVAL_M1(desc->bInterval - 1);
477		dep->interval = 1 << (desc->bInterval - 1);
478	}
479
480	return dwc3_send_gadget_ep_cmd(dwc, dep->number,
481			DWC3_DEPCMD_SETEPCONFIG, &params);
482}
483
484static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep)
485{
486	struct dwc3_gadget_ep_cmd_params params;
487
488	memset(&params, 0x00, sizeof(params));
489
490	params.param0 = DWC3_DEPXFERCFG_NUM_XFER_RES(1);
491
492	return dwc3_send_gadget_ep_cmd(dwc, dep->number,
493			DWC3_DEPCMD_SETTRANSFRESOURCE, &params);
494}
495
496/**
497 * __dwc3_gadget_ep_enable - Initializes a HW endpoint
498 * @dep: endpoint to be initialized
499 * @desc: USB Endpoint Descriptor
500 *
501 * Caller should take care of locking
502 */
503static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
504		const struct usb_endpoint_descriptor *desc,
505		const struct usb_ss_ep_comp_descriptor *comp_desc,
506		bool ignore)
507{
508	struct dwc3		*dwc = dep->dwc;
509	u32			reg;
510	int			ret = -ENOMEM;
511
512	if (!(dep->flags & DWC3_EP_ENABLED)) {
513		ret = dwc3_gadget_start_config(dwc, dep);
514		if (ret)
515			return ret;
516	}
517
518	ret = dwc3_gadget_set_ep_config(dwc, dep, desc, comp_desc, ignore);
519	if (ret)
520		return ret;
521
522	if (!(dep->flags & DWC3_EP_ENABLED)) {
523		struct dwc3_trb	*trb_st_hw;
524		struct dwc3_trb	*trb_link;
525
526		ret = dwc3_gadget_set_xfer_resource(dwc, dep);
527		if (ret)
528			return ret;
529
530		dep->endpoint.desc = desc;
531		dep->comp_desc = comp_desc;
532		dep->type = usb_endpoint_type(desc);
533		dep->flags |= DWC3_EP_ENABLED;
534
535		reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
536		reg |= DWC3_DALEPENA_EP(dep->number);
537		dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
538
539		if (!usb_endpoint_xfer_isoc(desc))
540			return 0;
541
542		memset(&trb_link, 0, sizeof(trb_link));
543
544		/* Link TRB for ISOC. The HWO bit is never reset */
545		trb_st_hw = &dep->trb_pool[0];
546
547		trb_link = &dep->trb_pool[DWC3_TRB_NUM - 1];
548
549		trb_link->bpl = lower_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
550		trb_link->bph = upper_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
551		trb_link->ctrl |= DWC3_TRBCTL_LINK_TRB;
552		trb_link->ctrl |= DWC3_TRB_CTRL_HWO;
553	}
554
555	return 0;
556}
557
558static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum);
559static void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep)
560{
561	struct dwc3_request		*req;
562
563	if (!list_empty(&dep->req_queued)) {
564		dwc3_stop_active_transfer(dwc, dep->number);
565
566		/* - giveback all requests to gadget driver */
567		while (!list_empty(&dep->req_queued)) {
568			req = next_request(&dep->req_queued);
569
570			dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
571		}
572	}
573
574	while (!list_empty(&dep->request_list)) {
575		req = next_request(&dep->request_list);
576
577		dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
578	}
579}
580
581/**
582 * __dwc3_gadget_ep_disable - Disables a HW endpoint
583 * @dep: the endpoint to disable
584 *
585 * This function also removes requests which are currently processed ny the
586 * hardware and those which are not yet scheduled.
587 * Caller should take care of locking.
588 */
589static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)
590{
591	struct dwc3		*dwc = dep->dwc;
592	u32			reg;
593
594	dwc3_remove_requests(dwc, dep);
595
596	reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
597	reg &= ~DWC3_DALEPENA_EP(dep->number);
598	dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
599
600	dep->stream_capable = false;
601	dep->endpoint.desc = NULL;
602	dep->comp_desc = NULL;
603	dep->type = 0;
604	dep->flags = 0;
605
606	return 0;
607}
608
609/* -------------------------------------------------------------------------- */
610
611static int dwc3_gadget_ep0_enable(struct usb_ep *ep,
612		const struct usb_endpoint_descriptor *desc)
613{
614	return -EINVAL;
615}
616
617static int dwc3_gadget_ep0_disable(struct usb_ep *ep)
618{
619	return -EINVAL;
620}
621
622/* -------------------------------------------------------------------------- */
623
624static int dwc3_gadget_ep_enable(struct usb_ep *ep,
625		const struct usb_endpoint_descriptor *desc)
626{
627	struct dwc3_ep			*dep;
628	struct dwc3			*dwc;
629	unsigned long			flags;
630	int				ret;
631
632	if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
633		pr_debug("dwc3: invalid parameters\n");
634		return -EINVAL;
635	}
636
637	if (!desc->wMaxPacketSize) {
638		pr_debug("dwc3: missing wMaxPacketSize\n");
639		return -EINVAL;
640	}
641
642	dep = to_dwc3_ep(ep);
643	dwc = dep->dwc;
644
645	if (dep->flags & DWC3_EP_ENABLED) {
646		dev_WARN_ONCE(dwc->dev, true, "%s is already enabled\n",
647				dep->name);
648		return 0;
649	}
650
651	switch (usb_endpoint_type(desc)) {
652	case USB_ENDPOINT_XFER_CONTROL:
653		strlcat(dep->name, "-control", sizeof(dep->name));
654		break;
655	case USB_ENDPOINT_XFER_ISOC:
656		strlcat(dep->name, "-isoc", sizeof(dep->name));
657		break;
658	case USB_ENDPOINT_XFER_BULK:
659		strlcat(dep->name, "-bulk", sizeof(dep->name));
660		break;
661	case USB_ENDPOINT_XFER_INT:
662		strlcat(dep->name, "-int", sizeof(dep->name));
663		break;
664	default:
665		dev_err(dwc->dev, "invalid endpoint transfer type\n");
666	}
667
668	dev_vdbg(dwc->dev, "Enabling %s\n", dep->name);
669
670	spin_lock_irqsave(&dwc->lock, flags);
671	ret = __dwc3_gadget_ep_enable(dep, desc, ep->comp_desc, false);
672	spin_unlock_irqrestore(&dwc->lock, flags);
673
674	return ret;
675}
676
677static int dwc3_gadget_ep_disable(struct usb_ep *ep)
678{
679	struct dwc3_ep			*dep;
680	struct dwc3			*dwc;
681	unsigned long			flags;
682	int				ret;
683
684	if (!ep) {
685		pr_debug("dwc3: invalid parameters\n");
686		return -EINVAL;
687	}
688
689	dep = to_dwc3_ep(ep);
690	dwc = dep->dwc;
691
692	if (!(dep->flags & DWC3_EP_ENABLED)) {
693		dev_WARN_ONCE(dwc->dev, true, "%s is already disabled\n",
694				dep->name);
695		return 0;
696	}
697
698	snprintf(dep->name, sizeof(dep->name), "ep%d%s",
699			dep->number >> 1,
700			(dep->number & 1) ? "in" : "out");
701
702	spin_lock_irqsave(&dwc->lock, flags);
703	ret = __dwc3_gadget_ep_disable(dep);
704	spin_unlock_irqrestore(&dwc->lock, flags);
705
706	return ret;
707}
708
709static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
710	gfp_t gfp_flags)
711{
712	struct dwc3_request		*req;
713	struct dwc3_ep			*dep = to_dwc3_ep(ep);
714	struct dwc3			*dwc = dep->dwc;
715
716	req = kzalloc(sizeof(*req), gfp_flags);
717	if (!req) {
718		dev_err(dwc->dev, "not enough memory\n");
719		return NULL;
720	}
721
722	req->epnum	= dep->number;
723	req->dep	= dep;
724
725	return &req->request;
726}
727
728static void dwc3_gadget_ep_free_request(struct usb_ep *ep,
729		struct usb_request *request)
730{
731	struct dwc3_request		*req = to_dwc3_request(request);
732
733	kfree(req);
734}
735
736/**
737 * dwc3_prepare_one_trb - setup one TRB from one request
738 * @dep: endpoint for which this request is prepared
739 * @req: dwc3_request pointer
740 */
741static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
742		struct dwc3_request *req, dma_addr_t dma,
743		unsigned length, unsigned last, unsigned chain)
744{
745	struct dwc3		*dwc = dep->dwc;
746	struct dwc3_trb		*trb;
747
748	unsigned int		cur_slot;
749
750	dev_vdbg(dwc->dev, "%s: req %p dma %08llx length %d%s%s\n",
751			dep->name, req, (unsigned long long) dma,
752			length, last ? " last" : "",
753			chain ? " chain" : "");
754
755	trb = &dep->trb_pool[dep->free_slot & DWC3_TRB_MASK];
756	cur_slot = dep->free_slot;
757	dep->free_slot++;
758
759	/* Skip the LINK-TRB on ISOC */
760	if (((cur_slot & DWC3_TRB_MASK) == DWC3_TRB_NUM - 1) &&
761			usb_endpoint_xfer_isoc(dep->endpoint.desc))
762		return;
763
764	if (!req->trb) {
765		dwc3_gadget_move_request_queued(req);
766		req->trb = trb;
767		req->trb_dma = dwc3_trb_dma_offset(dep, trb);
768	}
769
770	trb->size = DWC3_TRB_SIZE_LENGTH(length);
771	trb->bpl = lower_32_bits(dma);
772	trb->bph = upper_32_bits(dma);
773
774	switch (usb_endpoint_type(dep->endpoint.desc)) {
775	case USB_ENDPOINT_XFER_CONTROL:
776		trb->ctrl = DWC3_TRBCTL_CONTROL_SETUP;
777		break;
778
779	case USB_ENDPOINT_XFER_ISOC:
780		trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;
781
782		if (!req->request.no_interrupt)
783			trb->ctrl |= DWC3_TRB_CTRL_IOC;
784		break;
785
786	case USB_ENDPOINT_XFER_BULK:
787	case USB_ENDPOINT_XFER_INT:
788		trb->ctrl = DWC3_TRBCTL_NORMAL;
789		break;
790	default:
791		/*
792		 * This is only possible with faulty memory because we
793		 * checked it already :)
794		 */
795		BUG();
796	}
797
798	if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
799		trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
800		trb->ctrl |= DWC3_TRB_CTRL_CSP;
801	} else {
802		if (chain)
803			trb->ctrl |= DWC3_TRB_CTRL_CHN;
804
805		if (last)
806			trb->ctrl |= DWC3_TRB_CTRL_LST;
807	}
808
809	if (usb_endpoint_xfer_bulk(dep->endpoint.desc) && dep->stream_capable)
810		trb->ctrl |= DWC3_TRB_CTRL_SID_SOFN(req->request.stream_id);
811
812	trb->ctrl |= DWC3_TRB_CTRL_HWO;
813}
814
815/*
816 * dwc3_prepare_trbs - setup TRBs from requests
817 * @dep: endpoint for which requests are being prepared
818 * @starting: true if the endpoint is idle and no requests are queued.
819 *
820 * The function goes through the requests list and sets up TRBs for the
821 * transfers. The function returns once there are no more TRBs available or
822 * it runs out of requests.
823 */
824static void dwc3_prepare_trbs(struct dwc3_ep *dep, bool starting)
825{
826	struct dwc3_request	*req, *n;
827	u32			trbs_left;
828	u32			max;
829	unsigned int		last_one = 0;
830
831	BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
832
833	/* the first request must not be queued */
834	trbs_left = (dep->busy_slot - dep->free_slot) & DWC3_TRB_MASK;
835
836	/* Can't wrap around on a non-isoc EP since there's no link TRB */
837	if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
838		max = DWC3_TRB_NUM - (dep->free_slot & DWC3_TRB_MASK);
839		if (trbs_left > max)
840			trbs_left = max;
841	}
842
843	/*
844	 * If busy & slot are equal than it is either full or empty. If we are
845	 * starting to process requests then we are empty. Otherwise we are
846	 * full and don't do anything
847	 */
848	if (!trbs_left) {
849		if (!starting)
850			return;
851		trbs_left = DWC3_TRB_NUM;
852		/*
853		 * In case we start from scratch, we queue the ISOC requests
854		 * starting from slot 1. This is done because we use ring
855		 * buffer and have no LST bit to stop us. Instead, we place
856		 * IOC bit every TRB_NUM/4. We try to avoid having an interrupt
857		 * after the first request so we start at slot 1 and have
858		 * 7 requests proceed before we hit the first IOC.
859		 * Other transfer types don't use the ring buffer and are
860		 * processed from the first TRB until the last one. Since we
861		 * don't wrap around we have to start at the beginning.
862		 */
863		if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
864			dep->busy_slot = 1;
865			dep->free_slot = 1;
866		} else {
867			dep->busy_slot = 0;
868			dep->free_slot = 0;
869		}
870	}
871
872	/* The last TRB is a link TRB, not used for xfer */
873	if ((trbs_left <= 1) && usb_endpoint_xfer_isoc(dep->endpoint.desc))
874		return;
875
876	list_for_each_entry_safe(req, n, &dep->request_list, list) {
877		unsigned	length;
878		dma_addr_t	dma;
879
880		if (req->request.num_mapped_sgs > 0) {
881			struct usb_request *request = &req->request;
882			struct scatterlist *sg = request->sg;
883			struct scatterlist *s;
884			int		i;
885
886			for_each_sg(sg, s, request->num_mapped_sgs, i) {
887				unsigned chain = true;
888
889				length = sg_dma_len(s);
890				dma = sg_dma_address(s);
891
892				if (i == (request->num_mapped_sgs - 1) ||
893						sg_is_last(s)) {
894					last_one = true;
895					chain = false;
896				}
897
898				trbs_left--;
899				if (!trbs_left)
900					last_one = true;
901
902				if (last_one)
903					chain = false;
904
905				dwc3_prepare_one_trb(dep, req, dma, length,
906						last_one, chain);
907
908				if (last_one)
909					break;
910			}
911		} else {
912			dma = req->request.dma;
913			length = req->request.length;
914			trbs_left--;
915
916			if (!trbs_left)
917				last_one = 1;
918
919			/* Is this the last request? */
920			if (list_is_last(&req->list, &dep->request_list))
921				last_one = 1;
922
923			dwc3_prepare_one_trb(dep, req, dma, length,
924					last_one, false);
925
926			if (last_one)
927				break;
928		}
929	}
930}
931
932static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep, u16 cmd_param,
933		int start_new)
934{
935	struct dwc3_gadget_ep_cmd_params params;
936	struct dwc3_request		*req;
937	struct dwc3			*dwc = dep->dwc;
938	int				ret;
939	u32				cmd;
940
941	if (start_new && (dep->flags & DWC3_EP_BUSY)) {
942		dev_vdbg(dwc->dev, "%s: endpoint busy\n", dep->name);
943		return -EBUSY;
944	}
945	dep->flags &= ~DWC3_EP_PENDING_REQUEST;
946
947	/*
948	 * If we are getting here after a short-out-packet we don't enqueue any
949	 * new requests as we try to set the IOC bit only on the last request.
950	 */
951	if (start_new) {
952		if (list_empty(&dep->req_queued))
953			dwc3_prepare_trbs(dep, start_new);
954
955		/* req points to the first request which will be sent */
956		req = next_request(&dep->req_queued);
957	} else {
958		dwc3_prepare_trbs(dep, start_new);
959
960		/*
961		 * req points to the first request where HWO changed from 0 to 1
962		 */
963		req = next_request(&dep->req_queued);
964	}
965	if (!req) {
966		dep->flags |= DWC3_EP_PENDING_REQUEST;
967		return 0;
968	}
969
970	memset(&params, 0, sizeof(params));
971	params.param0 = upper_32_bits(req->trb_dma);
972	params.param1 = lower_32_bits(req->trb_dma);
973
974	if (start_new)
975		cmd = DWC3_DEPCMD_STARTTRANSFER;
976	else
977		cmd = DWC3_DEPCMD_UPDATETRANSFER;
978
979	cmd |= DWC3_DEPCMD_PARAM(cmd_param);
980	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
981	if (ret < 0) {
982		dev_dbg(dwc->dev, "failed to send STARTTRANSFER command\n");
983
984		/*
985		 * FIXME we need to iterate over the list of requests
986		 * here and stop, unmap, free and del each of the linked
987		 * requests instead of what we do now.
988		 */
989		usb_gadget_unmap_request(&dwc->gadget, &req->request,
990				req->direction);
991		list_del(&req->list);
992		return ret;
993	}
994
995	dep->flags |= DWC3_EP_BUSY;
996
997	if (start_new) {
998		dep->resource_index = dwc3_gadget_ep_get_transfer_index(dwc,
999				dep->number);
1000		WARN_ON_ONCE(!dep->resource_index);
1001	}
1002
1003	return 0;
1004}
1005
1006static void __dwc3_gadget_start_isoc(struct dwc3 *dwc,
1007		struct dwc3_ep *dep, u32 cur_uf)
1008{
1009	u32 uf;
1010
1011	if (list_empty(&dep->request_list)) {
1012		dev_vdbg(dwc->dev, "ISOC ep %s run out for requests.\n",
1013			dep->name);
1014		return;
1015	}
1016
1017	/* 4 micro frames in the future */
1018	uf = cur_uf + dep->interval * 4;
1019
1020	__dwc3_gadget_kick_transfer(dep, uf, 1);
1021}
1022
1023static void dwc3_gadget_start_isoc(struct dwc3 *dwc,
1024		struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
1025{
1026	u32 cur_uf, mask;
1027
1028	mask = ~(dep->interval - 1);
1029	cur_uf = event->parameters & mask;
1030
1031	__dwc3_gadget_start_isoc(dwc, dep, cur_uf);
1032}
1033
1034static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
1035{
1036	struct dwc3		*dwc = dep->dwc;
1037	int			ret;
1038
1039	req->request.actual	= 0;
1040	req->request.status	= -EINPROGRESS;
1041	req->direction		= dep->direction;
1042	req->epnum		= dep->number;
1043
1044	/*
1045	 * We only add to our list of requests now and
1046	 * start consuming the list once we get XferNotReady
1047	 * IRQ.
1048	 *
1049	 * That way, we avoid doing anything that we don't need
1050	 * to do now and defer it until the point we receive a
1051	 * particular token from the Host side.
1052	 *
1053	 * This will also avoid Host cancelling URBs due to too
1054	 * many NAKs.
1055	 */
1056	ret = usb_gadget_map_request(&dwc->gadget, &req->request,
1057			dep->direction);
1058	if (ret)
1059		return ret;
1060
1061	list_add_tail(&req->list, &dep->request_list);
1062
1063	/*
1064	 * There are a few special cases:
1065	 *
1066	 * 1. XferNotReady with empty list of requests. We need to kick the
1067	 *    transfer here in that situation, otherwise we will be NAKing
1068	 *    forever. If we get XferNotReady before gadget driver has a
1069	 *    chance to queue a request, we will ACK the IRQ but won't be
1070	 *    able to receive the data until the next request is queued.
1071	 *    The following code is handling exactly that.
1072	 *
1073	 */
1074	if (dep->flags & DWC3_EP_PENDING_REQUEST) {
1075		ret = __dwc3_gadget_kick_transfer(dep, 0, true);
1076		if (ret && ret != -EBUSY)
1077			dev_dbg(dwc->dev, "%s: failed to kick transfers\n",
1078					dep->name);
1079	}
1080
1081	/*
1082	 * 2. XferInProgress on Isoc EP with an active transfer. We need to
1083	 *    kick the transfer here after queuing a request, otherwise the
1084	 *    core may not see the modified TRB(s).
1085	 */
1086	if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
1087			(dep->flags & DWC3_EP_BUSY) &&
1088			!(dep->flags & DWC3_EP_MISSED_ISOC)) {
1089		WARN_ON_ONCE(!dep->resource_index);
1090		ret = __dwc3_gadget_kick_transfer(dep, dep->resource_index,
1091				false);
1092		if (ret && ret != -EBUSY)
1093			dev_dbg(dwc->dev, "%s: failed to kick transfers\n",
1094					dep->name);
1095	}
1096
1097	/*
1098	 * 3. Missed ISOC Handling. We need to start isoc transfer on the saved
1099	 * uframe number.
1100	 */
1101	if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
1102		(dep->flags & DWC3_EP_MISSED_ISOC)) {
1103			__dwc3_gadget_start_isoc(dwc, dep, dep->current_uf);
1104			dep->flags &= ~DWC3_EP_MISSED_ISOC;
1105	}
1106
1107	return 0;
1108}
1109
1110static int dwc3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
1111	gfp_t gfp_flags)
1112{
1113	struct dwc3_request		*req = to_dwc3_request(request);
1114	struct dwc3_ep			*dep = to_dwc3_ep(ep);
1115	struct dwc3			*dwc = dep->dwc;
1116
1117	unsigned long			flags;
1118
1119	int				ret;
1120
1121	if (!dep->endpoint.desc) {
1122		dev_dbg(dwc->dev, "trying to queue request %p to disabled %s\n",
1123				request, ep->name);
1124		return -ESHUTDOWN;
1125	}
1126
1127	dev_vdbg(dwc->dev, "queing request %p to %s length %d\n",
1128			request, ep->name, request->length);
1129
1130	spin_lock_irqsave(&dwc->lock, flags);
1131	ret = __dwc3_gadget_ep_queue(dep, req);
1132	spin_unlock_irqrestore(&dwc->lock, flags);
1133
1134	return ret;
1135}
1136
1137static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
1138		struct usb_request *request)
1139{
1140	struct dwc3_request		*req = to_dwc3_request(request);
1141	struct dwc3_request		*r = NULL;
1142
1143	struct dwc3_ep			*dep = to_dwc3_ep(ep);
1144	struct dwc3			*dwc = dep->dwc;
1145
1146	unsigned long			flags;
1147	int				ret = 0;
1148
1149	spin_lock_irqsave(&dwc->lock, flags);
1150
1151	list_for_each_entry(r, &dep->request_list, list) {
1152		if (r == req)
1153			break;
1154	}
1155
1156	if (r != req) {
1157		list_for_each_entry(r, &dep->req_queued, list) {
1158			if (r == req)
1159				break;
1160		}
1161		if (r == req) {
1162			/* wait until it is processed */
1163			dwc3_stop_active_transfer(dwc, dep->number);
1164			goto out1;
1165		}
1166		dev_err(dwc->dev, "request %p was not queued to %s\n",
1167				request, ep->name);
1168		ret = -EINVAL;
1169		goto out0;
1170	}
1171
1172out1:
1173	/* giveback the request */
1174	dwc3_gadget_giveback(dep, req, -ECONNRESET);
1175
1176out0:
1177	spin_unlock_irqrestore(&dwc->lock, flags);
1178
1179	return ret;
1180}
1181
1182int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value)
1183{
1184	struct dwc3_gadget_ep_cmd_params	params;
1185	struct dwc3				*dwc = dep->dwc;
1186	int					ret;
1187
1188	memset(&params, 0x00, sizeof(params));
1189
1190	if (value) {
1191		ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
1192			DWC3_DEPCMD_SETSTALL, &params);
1193		if (ret)
1194			dev_err(dwc->dev, "failed to %s STALL on %s\n",
1195					value ? "set" : "clear",
1196					dep->name);
1197		else
1198			dep->flags |= DWC3_EP_STALL;
1199	} else {
1200		if (dep->flags & DWC3_EP_WEDGE)
1201			return 0;
1202
1203		ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
1204			DWC3_DEPCMD_CLEARSTALL, &params);
1205		if (ret)
1206			dev_err(dwc->dev, "failed to %s STALL on %s\n",
1207					value ? "set" : "clear",
1208					dep->name);
1209		else
1210			dep->flags &= ~DWC3_EP_STALL;
1211	}
1212
1213	return ret;
1214}
1215
1216static int dwc3_gadget_ep_set_halt(struct usb_ep *ep, int value)
1217{
1218	struct dwc3_ep			*dep = to_dwc3_ep(ep);
1219	struct dwc3			*dwc = dep->dwc;
1220
1221	unsigned long			flags;
1222
1223	int				ret;
1224
1225	spin_lock_irqsave(&dwc->lock, flags);
1226
1227	if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1228		dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
1229		ret = -EINVAL;
1230		goto out;
1231	}
1232
1233	ret = __dwc3_gadget_ep_set_halt(dep, value);
1234out:
1235	spin_unlock_irqrestore(&dwc->lock, flags);
1236
1237	return ret;
1238}
1239
1240static int dwc3_gadget_ep_set_wedge(struct usb_ep *ep)
1241{
1242	struct dwc3_ep			*dep = to_dwc3_ep(ep);
1243	struct dwc3			*dwc = dep->dwc;
1244	unsigned long			flags;
1245
1246	spin_lock_irqsave(&dwc->lock, flags);
1247	dep->flags |= DWC3_EP_WEDGE;
1248	spin_unlock_irqrestore(&dwc->lock, flags);
1249
1250	if (dep->number == 0 || dep->number == 1)
1251		return dwc3_gadget_ep0_set_halt(ep, 1);
1252	else
1253		return dwc3_gadget_ep_set_halt(ep, 1);
1254}
1255
1256/* -------------------------------------------------------------------------- */
1257
1258static struct usb_endpoint_descriptor dwc3_gadget_ep0_desc = {
1259	.bLength	= USB_DT_ENDPOINT_SIZE,
1260	.bDescriptorType = USB_DT_ENDPOINT,
1261	.bmAttributes	= USB_ENDPOINT_XFER_CONTROL,
1262};
1263
1264static const struct usb_ep_ops dwc3_gadget_ep0_ops = {
1265	.enable		= dwc3_gadget_ep0_enable,
1266	.disable	= dwc3_gadget_ep0_disable,
1267	.alloc_request	= dwc3_gadget_ep_alloc_request,
1268	.free_request	= dwc3_gadget_ep_free_request,
1269	.queue		= dwc3_gadget_ep0_queue,
1270	.dequeue	= dwc3_gadget_ep_dequeue,
1271	.set_halt	= dwc3_gadget_ep0_set_halt,
1272	.set_wedge	= dwc3_gadget_ep_set_wedge,
1273};
1274
1275static const struct usb_ep_ops dwc3_gadget_ep_ops = {
1276	.enable		= dwc3_gadget_ep_enable,
1277	.disable	= dwc3_gadget_ep_disable,
1278	.alloc_request	= dwc3_gadget_ep_alloc_request,
1279	.free_request	= dwc3_gadget_ep_free_request,
1280	.queue		= dwc3_gadget_ep_queue,
1281	.dequeue	= dwc3_gadget_ep_dequeue,
1282	.set_halt	= dwc3_gadget_ep_set_halt,
1283	.set_wedge	= dwc3_gadget_ep_set_wedge,
1284};
1285
1286/* -------------------------------------------------------------------------- */
1287
1288static int dwc3_gadget_get_frame(struct usb_gadget *g)
1289{
1290	struct dwc3		*dwc = gadget_to_dwc(g);
1291	u32			reg;
1292
1293	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1294	return DWC3_DSTS_SOFFN(reg);
1295}
1296
1297static int dwc3_gadget_wakeup(struct usb_gadget *g)
1298{
1299	struct dwc3		*dwc = gadget_to_dwc(g);
1300
1301	unsigned long		timeout;
1302	unsigned long		flags;
1303
1304	u32			reg;
1305
1306	int			ret = 0;
1307
1308	u8			link_state;
1309	u8			speed;
1310
1311	spin_lock_irqsave(&dwc->lock, flags);
1312
1313	/*
1314	 * According to the Databook Remote wakeup request should
1315	 * be issued only when the device is in early suspend state.
1316	 *
1317	 * We can check that via USB Link State bits in DSTS register.
1318	 */
1319	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1320
1321	speed = reg & DWC3_DSTS_CONNECTSPD;
1322	if (speed == DWC3_DSTS_SUPERSPEED) {
1323		dev_dbg(dwc->dev, "no wakeup on SuperSpeed\n");
1324		ret = -EINVAL;
1325		goto out;
1326	}
1327
1328	link_state = DWC3_DSTS_USBLNKST(reg);
1329
1330	switch (link_state) {
1331	case DWC3_LINK_STATE_RX_DET:	/* in HS, means Early Suspend */
1332	case DWC3_LINK_STATE_U3:	/* in HS, means SUSPEND */
1333		break;
1334	default:
1335		dev_dbg(dwc->dev, "can't wakeup from link state %d\n",
1336				link_state);
1337		ret = -EINVAL;
1338		goto out;
1339	}
1340
1341	ret = dwc3_gadget_set_link_state(dwc, DWC3_LINK_STATE_RECOV);
1342	if (ret < 0) {
1343		dev_err(dwc->dev, "failed to put link in Recovery\n");
1344		goto out;
1345	}
1346
1347	/* Recent versions do this automatically */
1348	if (dwc->revision < DWC3_REVISION_194A) {
1349		/* write zeroes to Link Change Request */
1350		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1351		reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
1352		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1353	}
1354
1355	/* poll until Link State changes to ON */
1356	timeout = jiffies + msecs_to_jiffies(100);
1357
1358	while (!time_after(jiffies, timeout)) {
1359		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1360
1361		/* in HS, means ON */
1362		if (DWC3_DSTS_USBLNKST(reg) == DWC3_LINK_STATE_U0)
1363			break;
1364	}
1365
1366	if (DWC3_DSTS_USBLNKST(reg) != DWC3_LINK_STATE_U0) {
1367		dev_err(dwc->dev, "failed to send remote wakeup\n");
1368		ret = -EINVAL;
1369	}
1370
1371out:
1372	spin_unlock_irqrestore(&dwc->lock, flags);
1373
1374	return ret;
1375}
1376
1377static int dwc3_gadget_set_selfpowered(struct usb_gadget *g,
1378		int is_selfpowered)
1379{
1380	struct dwc3		*dwc = gadget_to_dwc(g);
1381	unsigned long		flags;
1382
1383	spin_lock_irqsave(&dwc->lock, flags);
1384	dwc->is_selfpowered = !!is_selfpowered;
1385	spin_unlock_irqrestore(&dwc->lock, flags);
1386
1387	return 0;
1388}
1389
1390static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on)
1391{
1392	u32			reg;
1393	u32			timeout = 500;
1394
1395	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1396	if (is_on) {
1397		if (dwc->revision <= DWC3_REVISION_187A) {
1398			reg &= ~DWC3_DCTL_TRGTULST_MASK;
1399			reg |= DWC3_DCTL_TRGTULST_RX_DET;
1400		}
1401
1402		if (dwc->revision >= DWC3_REVISION_194A)
1403			reg &= ~DWC3_DCTL_KEEP_CONNECT;
1404		reg |= DWC3_DCTL_RUN_STOP;
1405	} else {
1406		reg &= ~DWC3_DCTL_RUN_STOP;
1407	}
1408
1409	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1410
1411	do {
1412		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1413		if (is_on) {
1414			if (!(reg & DWC3_DSTS_DEVCTRLHLT))
1415				break;
1416		} else {
1417			if (reg & DWC3_DSTS_DEVCTRLHLT)
1418				break;
1419		}
1420		timeout--;
1421		if (!timeout)
1422			return -ETIMEDOUT;
1423		udelay(1);
1424	} while (1);
1425
1426	dev_vdbg(dwc->dev, "gadget %s data soft-%s\n",
1427			dwc->gadget_driver
1428			? dwc->gadget_driver->function : "no-function",
1429			is_on ? "connect" : "disconnect");
1430
1431	return 0;
1432}
1433
1434static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
1435{
1436	struct dwc3		*dwc = gadget_to_dwc(g);
1437	unsigned long		flags;
1438	int			ret;
1439
1440	is_on = !!is_on;
1441
1442	spin_lock_irqsave(&dwc->lock, flags);
1443	ret = dwc3_gadget_run_stop(dwc, is_on);
1444	spin_unlock_irqrestore(&dwc->lock, flags);
1445
1446	return ret;
1447}
1448
1449static int dwc3_gadget_start(struct usb_gadget *g,
1450		struct usb_gadget_driver *driver)
1451{
1452	struct dwc3		*dwc = gadget_to_dwc(g);
1453	struct dwc3_ep		*dep;
1454	unsigned long		flags;
1455	int			ret = 0;
1456	u32			reg;
1457
1458	spin_lock_irqsave(&dwc->lock, flags);
1459
1460	if (dwc->gadget_driver) {
1461		dev_err(dwc->dev, "%s is already bound to %s\n",
1462				dwc->gadget.name,
1463				dwc->gadget_driver->driver.name);
1464		ret = -EBUSY;
1465		goto err0;
1466	}
1467
1468	dwc->gadget_driver	= driver;
1469	dwc->gadget.dev.driver	= &driver->driver;
1470
1471	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
1472	reg &= ~(DWC3_DCFG_SPEED_MASK);
1473
1474	/**
1475	 * WORKAROUND: DWC3 revision < 2.20a have an issue
1476	 * which would cause metastability state on Run/Stop
1477	 * bit if we try to force the IP to USB2-only mode.
1478	 *
1479	 * Because of that, we cannot configure the IP to any
1480	 * speed other than the SuperSpeed
1481	 *
1482	 * Refers to:
1483	 *
1484	 * STAR#9000525659: Clock Domain Crossing on DCTL in
1485	 * USB 2.0 Mode
1486	 */
1487	if (dwc->revision < DWC3_REVISION_220A)
1488		reg |= DWC3_DCFG_SUPERSPEED;
1489	else
1490		reg |= dwc->maximum_speed;
1491	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
1492
1493	dwc->start_config_issued = false;
1494
1495	/* Start with SuperSpeed Default */
1496	dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
1497
1498	dep = dwc->eps[0];
1499	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false);
1500	if (ret) {
1501		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1502		goto err0;
1503	}
1504
1505	dep = dwc->eps[1];
1506	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, false);
1507	if (ret) {
1508		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1509		goto err1;
1510	}
1511
1512	/* begin to receive SETUP packets */
1513	dwc->ep0state = EP0_SETUP_PHASE;
1514	dwc3_ep0_out_start(dwc);
1515
1516	spin_unlock_irqrestore(&dwc->lock, flags);
1517
1518	return 0;
1519
1520err1:
1521	__dwc3_gadget_ep_disable(dwc->eps[0]);
1522
1523err0:
1524	spin_unlock_irqrestore(&dwc->lock, flags);
1525
1526	return ret;
1527}
1528
1529static int dwc3_gadget_stop(struct usb_gadget *g,
1530		struct usb_gadget_driver *driver)
1531{
1532	struct dwc3		*dwc = gadget_to_dwc(g);
1533	unsigned long		flags;
1534
1535	spin_lock_irqsave(&dwc->lock, flags);
1536
1537	__dwc3_gadget_ep_disable(dwc->eps[0]);
1538	__dwc3_gadget_ep_disable(dwc->eps[1]);
1539
1540	dwc->gadget_driver	= NULL;
1541	dwc->gadget.dev.driver	= NULL;
1542
1543	spin_unlock_irqrestore(&dwc->lock, flags);
1544
1545	return 0;
1546}
1547
1548static const struct usb_gadget_ops dwc3_gadget_ops = {
1549	.get_frame		= dwc3_gadget_get_frame,
1550	.wakeup			= dwc3_gadget_wakeup,
1551	.set_selfpowered	= dwc3_gadget_set_selfpowered,
1552	.pullup			= dwc3_gadget_pullup,
1553	.udc_start		= dwc3_gadget_start,
1554	.udc_stop		= dwc3_gadget_stop,
1555};
1556
1557/* -------------------------------------------------------------------------- */
1558
1559static int __devinit dwc3_gadget_init_endpoints(struct dwc3 *dwc)
1560{
1561	struct dwc3_ep			*dep;
1562	u8				epnum;
1563
1564	INIT_LIST_HEAD(&dwc->gadget.ep_list);
1565
1566	for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
1567		dep = kzalloc(sizeof(*dep), GFP_KERNEL);
1568		if (!dep) {
1569			dev_err(dwc->dev, "can't allocate endpoint %d\n",
1570					epnum);
1571			return -ENOMEM;
1572		}
1573
1574		dep->dwc = dwc;
1575		dep->number = epnum;
1576		dwc->eps[epnum] = dep;
1577
1578		snprintf(dep->name, sizeof(dep->name), "ep%d%s", epnum >> 1,
1579				(epnum & 1) ? "in" : "out");
1580		dep->endpoint.name = dep->name;
1581		dep->direction = (epnum & 1);
1582
1583		if (epnum == 0 || epnum == 1) {
1584			dep->endpoint.maxpacket = 512;
1585			dep->endpoint.ops = &dwc3_gadget_ep0_ops;
1586			if (!epnum)
1587				dwc->gadget.ep0 = &dep->endpoint;
1588		} else {
1589			int		ret;
1590
1591			dep->endpoint.maxpacket = 1024;
1592			dep->endpoint.max_streams = 15;
1593			dep->endpoint.ops = &dwc3_gadget_ep_ops;
1594			list_add_tail(&dep->endpoint.ep_list,
1595					&dwc->gadget.ep_list);
1596
1597			ret = dwc3_alloc_trb_pool(dep);
1598			if (ret)
1599				return ret;
1600		}
1601
1602		INIT_LIST_HEAD(&dep->request_list);
1603		INIT_LIST_HEAD(&dep->req_queued);
1604	}
1605
1606	return 0;
1607}
1608
1609static void dwc3_gadget_free_endpoints(struct dwc3 *dwc)
1610{
1611	struct dwc3_ep			*dep;
1612	u8				epnum;
1613
1614	for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
1615		dep = dwc->eps[epnum];
1616		dwc3_free_trb_pool(dep);
1617
1618		if (epnum != 0 && epnum != 1)
1619			list_del(&dep->endpoint.ep_list);
1620
1621		kfree(dep);
1622	}
1623}
1624
1625static void dwc3_gadget_release(struct device *dev)
1626{
1627	dev_dbg(dev, "%s\n", __func__);
1628}
1629
1630/* -------------------------------------------------------------------------- */
1631static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
1632		const struct dwc3_event_depevt *event, int status)
1633{
1634	struct dwc3_request	*req;
1635	struct dwc3_trb		*trb;
1636	unsigned int		count;
1637	unsigned int		s_pkt = 0;
1638	unsigned int		trb_status;
1639
1640	do {
1641		req = next_request(&dep->req_queued);
1642		if (!req) {
1643			WARN_ON_ONCE(1);
1644			return 1;
1645		}
1646
1647		trb = req->trb;
1648
1649		if ((trb->ctrl & DWC3_TRB_CTRL_HWO) && status != -ESHUTDOWN)
1650			/*
1651			 * We continue despite the error. There is not much we
1652			 * can do. If we don't clean it up we loop forever. If
1653			 * we skip the TRB then it gets overwritten after a
1654			 * while since we use them in a ring buffer. A BUG()
1655			 * would help. Lets hope that if this occurs, someone
1656			 * fixes the root cause instead of looking away :)
1657			 */
1658			dev_err(dwc->dev, "%s's TRB (%p) still owned by HW\n",
1659					dep->name, req->trb);
1660		count = trb->size & DWC3_TRB_SIZE_MASK;
1661
1662		if (dep->direction) {
1663			if (count) {
1664				trb_status = DWC3_TRB_SIZE_TRBSTS(trb->size);
1665				if (trb_status == DWC3_TRBSTS_MISSED_ISOC) {
1666					dev_dbg(dwc->dev, "incomplete IN transfer %s\n",
1667							dep->name);
1668					dep->current_uf = event->parameters &
1669						~(dep->interval - 1);
1670					dep->flags |= DWC3_EP_MISSED_ISOC;
1671				} else {
1672					dev_err(dwc->dev, "incomplete IN transfer %s\n",
1673							dep->name);
1674					status = -ECONNRESET;
1675				}
1676			}
1677		} else {
1678			if (count && (event->status & DEPEVT_STATUS_SHORT))
1679				s_pkt = 1;
1680		}
1681
1682		/*
1683		 * We assume here we will always receive the entire data block
1684		 * which we should receive. Meaning, if we program RX to
1685		 * receive 4K but we receive only 2K, we assume that's all we
1686		 * should receive and we simply bounce the request back to the
1687		 * gadget driver for further processing.
1688		 */
1689		req->request.actual += req->request.length - count;
1690		dwc3_gadget_giveback(dep, req, status);
1691		if (s_pkt)
1692			break;
1693		if ((event->status & DEPEVT_STATUS_LST) &&
1694				(trb->ctrl & (DWC3_TRB_CTRL_LST |
1695						DWC3_TRB_CTRL_HWO)))
1696			break;
1697		if ((event->status & DEPEVT_STATUS_IOC) &&
1698				(trb->ctrl & DWC3_TRB_CTRL_IOC))
1699			break;
1700	} while (1);
1701
1702	if ((event->status & DEPEVT_STATUS_IOC) &&
1703			(trb->ctrl & DWC3_TRB_CTRL_IOC))
1704		return 0;
1705	return 1;
1706}
1707
1708static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc,
1709		struct dwc3_ep *dep, const struct dwc3_event_depevt *event,
1710		int start_new)
1711{
1712	unsigned		status = 0;
1713	int			clean_busy;
1714
1715	if (event->status & DEPEVT_STATUS_BUSERR)
1716		status = -ECONNRESET;
1717
1718	clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status);
1719	if (clean_busy)
1720		dep->flags &= ~DWC3_EP_BUSY;
1721
1722	/*
1723	 * WORKAROUND: This is the 2nd half of U1/U2 -> U0 workaround.
1724	 * See dwc3_gadget_linksts_change_interrupt() for 1st half.
1725	 */
1726	if (dwc->revision < DWC3_REVISION_183A) {
1727		u32		reg;
1728		int		i;
1729
1730		for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
1731			dep = dwc->eps[i];
1732
1733			if (!(dep->flags & DWC3_EP_ENABLED))
1734				continue;
1735
1736			if (!list_empty(&dep->req_queued))
1737				return;
1738		}
1739
1740		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1741		reg |= dwc->u1u2;
1742		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1743
1744		dwc->u1u2 = 0;
1745	}
1746}
1747
1748static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
1749		const struct dwc3_event_depevt *event)
1750{
1751	struct dwc3_ep		*dep;
1752	u8			epnum = event->endpoint_number;
1753
1754	dep = dwc->eps[epnum];
1755
1756	if (!(dep->flags & DWC3_EP_ENABLED))
1757		return;
1758
1759	dev_vdbg(dwc->dev, "%s: %s\n", dep->name,
1760			dwc3_ep_event_string(event->endpoint_event));
1761
1762	if (epnum == 0 || epnum == 1) {
1763		dwc3_ep0_interrupt(dwc, event);
1764		return;
1765	}
1766
1767	switch (event->endpoint_event) {
1768	case DWC3_DEPEVT_XFERCOMPLETE:
1769		dep->resource_index = 0;
1770
1771		if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1772			dev_dbg(dwc->dev, "%s is an Isochronous endpoint\n",
1773					dep->name);
1774			return;
1775		}
1776
1777		dwc3_endpoint_transfer_complete(dwc, dep, event, 1);
1778		break;
1779	case DWC3_DEPEVT_XFERINPROGRESS:
1780		if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1781			dev_dbg(dwc->dev, "%s is not an Isochronous endpoint\n",
1782					dep->name);
1783			return;
1784		}
1785
1786		dwc3_endpoint_transfer_complete(dwc, dep, event, 0);
1787		break;
1788	case DWC3_DEPEVT_XFERNOTREADY:
1789		if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1790			dwc3_gadget_start_isoc(dwc, dep, event);
1791		} else {
1792			int ret;
1793
1794			dev_vdbg(dwc->dev, "%s: reason %s\n",
1795					dep->name, event->status &
1796					DEPEVT_STATUS_TRANSFER_ACTIVE
1797					? "Transfer Active"
1798					: "Transfer Not Active");
1799
1800			ret = __dwc3_gadget_kick_transfer(dep, 0, 1);
1801			if (!ret || ret == -EBUSY)
1802				return;
1803
1804			dev_dbg(dwc->dev, "%s: failed to kick transfers\n",
1805					dep->name);
1806		}
1807
1808		break;
1809	case DWC3_DEPEVT_STREAMEVT:
1810		if (!usb_endpoint_xfer_bulk(dep->endpoint.desc)) {
1811			dev_err(dwc->dev, "Stream event for non-Bulk %s\n",
1812					dep->name);
1813			return;
1814		}
1815
1816		switch (event->status) {
1817		case DEPEVT_STREAMEVT_FOUND:
1818			dev_vdbg(dwc->dev, "Stream %d found and started\n",
1819					event->parameters);
1820
1821			break;
1822		case DEPEVT_STREAMEVT_NOTFOUND:
1823			/* FALLTHROUGH */
1824		default:
1825			dev_dbg(dwc->dev, "Couldn't find suitable stream\n");
1826		}
1827		break;
1828	case DWC3_DEPEVT_RXTXFIFOEVT:
1829		dev_dbg(dwc->dev, "%s FIFO Overrun\n", dep->name);
1830		break;
1831	case DWC3_DEPEVT_EPCMDCMPLT:
1832		dev_vdbg(dwc->dev, "Endpoint Command Complete\n");
1833		break;
1834	}
1835}
1836
1837static void dwc3_disconnect_gadget(struct dwc3 *dwc)
1838{
1839	if (dwc->gadget_driver && dwc->gadget_driver->disconnect) {
1840		spin_unlock(&dwc->lock);
1841		dwc->gadget_driver->disconnect(&dwc->gadget);
1842		spin_lock(&dwc->lock);
1843	}
1844}
1845
1846static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum)
1847{
1848	struct dwc3_ep *dep;
1849	struct dwc3_gadget_ep_cmd_params params;
1850	u32 cmd;
1851	int ret;
1852
1853	dep = dwc->eps[epnum];
1854
1855	if (!dep->resource_index)
1856		return;
1857
1858	/*
1859	 * NOTICE: We are violating what the Databook says about the
1860	 * EndTransfer command. Ideally we would _always_ wait for the
1861	 * EndTransfer Command Completion IRQ, but that's causing too
1862	 * much trouble synchronizing between us and gadget driver.
1863	 *
1864	 * We have discussed this with the IP Provider and it was
1865	 * suggested to giveback all requests here, but give HW some
1866	 * extra time to synchronize with the interconnect. We're using
1867	 * an arbitraty 100us delay for that.
1868	 *
1869	 * Note also that a similar handling was tested by Synopsys
1870	 * (thanks a lot Paul) and nothing bad has come out of it.
1871	 * In short, what we're doing is:
1872	 *
1873	 * - Issue EndTransfer WITH CMDIOC bit set
1874	 * - Wait 100us
1875	 */
1876
1877	cmd = DWC3_DEPCMD_ENDTRANSFER;
1878	cmd |= DWC3_DEPCMD_HIPRI_FORCERM | DWC3_DEPCMD_CMDIOC;
1879	cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
1880	memset(&params, 0, sizeof(params));
1881	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number, cmd, &params);
1882	WARN_ON_ONCE(ret);
1883	dep->resource_index = 0;
1884
1885	udelay(100);
1886}
1887
1888static void dwc3_stop_active_transfers(struct dwc3 *dwc)
1889{
1890	u32 epnum;
1891
1892	for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
1893		struct dwc3_ep *dep;
1894
1895		dep = dwc->eps[epnum];
1896		if (!(dep->flags & DWC3_EP_ENABLED))
1897			continue;
1898
1899		dwc3_remove_requests(dwc, dep);
1900	}
1901}
1902
1903static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
1904{
1905	u32 epnum;
1906
1907	for (epnum = 1; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
1908		struct dwc3_ep *dep;
1909		struct dwc3_gadget_ep_cmd_params params;
1910		int ret;
1911
1912		dep = dwc->eps[epnum];
1913
1914		if (!(dep->flags & DWC3_EP_STALL))
1915			continue;
1916
1917		dep->flags &= ~DWC3_EP_STALL;
1918
1919		memset(&params, 0, sizeof(params));
1920		ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
1921				DWC3_DEPCMD_CLEARSTALL, &params);
1922		WARN_ON_ONCE(ret);
1923	}
1924}
1925
1926static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
1927{
1928	int			reg;
1929
1930	dev_vdbg(dwc->dev, "%s\n", __func__);
1931
1932	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1933	reg &= ~DWC3_DCTL_INITU1ENA;
1934	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1935
1936	reg &= ~DWC3_DCTL_INITU2ENA;
1937	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1938
1939	dwc3_disconnect_gadget(dwc);
1940	dwc->start_config_issued = false;
1941
1942	dwc->gadget.speed = USB_SPEED_UNKNOWN;
1943	dwc->setup_packet_pending = false;
1944}
1945
1946static void dwc3_gadget_usb3_phy_suspend(struct dwc3 *dwc, int suspend)
1947{
1948	u32			reg;
1949
1950	reg = dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0));
1951
1952	if (suspend)
1953		reg |= DWC3_GUSB3PIPECTL_SUSPHY;
1954	else
1955		reg &= ~DWC3_GUSB3PIPECTL_SUSPHY;
1956
1957	dwc3_writel(dwc->regs, DWC3_GUSB3PIPECTL(0), reg);
1958}
1959
1960static void dwc3_gadget_usb2_phy_suspend(struct dwc3 *dwc, int suspend)
1961{
1962	u32			reg;
1963
1964	reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
1965
1966	if (suspend)
1967		reg |= DWC3_GUSB2PHYCFG_SUSPHY;
1968	else
1969		reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
1970
1971	dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
1972}
1973
1974static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
1975{
1976	u32			reg;
1977
1978	dev_vdbg(dwc->dev, "%s\n", __func__);
1979
1980	/*
1981	 * WORKAROUND: DWC3 revisions <1.88a have an issue which
1982	 * would cause a missing Disconnect Event if there's a
1983	 * pending Setup Packet in the FIFO.
1984	 *
1985	 * There's no suggested workaround on the official Bug
1986	 * report, which states that "unless the driver/application
1987	 * is doing any special handling of a disconnect event,
1988	 * there is no functional issue".
1989	 *
1990	 * Unfortunately, it turns out that we _do_ some special
1991	 * handling of a disconnect event, namely complete all
1992	 * pending transfers, notify gadget driver of the
1993	 * disconnection, and so on.
1994	 *
1995	 * Our suggested workaround is to follow the Disconnect
1996	 * Event steps here, instead, based on a setup_packet_pending
1997	 * flag. Such flag gets set whenever we have a XferNotReady
1998	 * event on EP0 and gets cleared on XferComplete for the
1999	 * same endpoint.
2000	 *
2001	 * Refers to:
2002	 *
2003	 * STAR#9000466709: RTL: Device : Disconnect event not
2004	 * generated if setup packet pending in FIFO
2005	 */
2006	if (dwc->revision < DWC3_REVISION_188A) {
2007		if (dwc->setup_packet_pending)
2008			dwc3_gadget_disconnect_interrupt(dwc);
2009	}
2010
2011	/* after reset -> Default State */
2012	dwc->dev_state = DWC3_DEFAULT_STATE;
2013
2014	/* Recent versions support automatic phy suspend and don't need this */
2015	if (dwc->revision < DWC3_REVISION_194A) {
2016		/* Resume PHYs */
2017		dwc3_gadget_usb2_phy_suspend(dwc, false);
2018		dwc3_gadget_usb3_phy_suspend(dwc, false);
2019	}
2020
2021	if (dwc->gadget.speed != USB_SPEED_UNKNOWN)
2022		dwc3_disconnect_gadget(dwc);
2023
2024	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2025	reg &= ~DWC3_DCTL_TSTCTRL_MASK;
2026	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2027	dwc->test_mode = false;
2028
2029	dwc3_stop_active_transfers(dwc);
2030	dwc3_clear_stall_all_ep(dwc);
2031	dwc->start_config_issued = false;
2032
2033	/* Reset device address to zero */
2034	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2035	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
2036	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2037}
2038
2039static void dwc3_update_ram_clk_sel(struct dwc3 *dwc, u32 speed)
2040{
2041	u32 reg;
2042	u32 usb30_clock = DWC3_GCTL_CLK_BUS;
2043
2044	/*
2045	 * We change the clock only at SS but I dunno why I would want to do
2046	 * this. Maybe it becomes part of the power saving plan.
2047	 */
2048
2049	if (speed != DWC3_DSTS_SUPERSPEED)
2050		return;
2051
2052	/*
2053	 * RAMClkSel is reset to 0 after USB reset, so it must be reprogrammed
2054	 * each time on Connect Done.
2055	 */
2056	if (!usb30_clock)
2057		return;
2058
2059	reg = dwc3_readl(dwc->regs, DWC3_GCTL);
2060	reg |= DWC3_GCTL_RAMCLKSEL(usb30_clock);
2061	dwc3_writel(dwc->regs, DWC3_GCTL, reg);
2062}
2063
2064static void dwc3_gadget_phy_suspend(struct dwc3 *dwc, u8 speed)
2065{
2066	switch (speed) {
2067	case USB_SPEED_SUPER:
2068		dwc3_gadget_usb2_phy_suspend(dwc, true);
2069		break;
2070	case USB_SPEED_HIGH:
2071	case USB_SPEED_FULL:
2072	case USB_SPEED_LOW:
2073		dwc3_gadget_usb3_phy_suspend(dwc, true);
2074		break;
2075	}
2076}
2077
2078static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
2079{
2080	struct dwc3_gadget_ep_cmd_params params;
2081	struct dwc3_ep		*dep;
2082	int			ret;
2083	u32			reg;
2084	u8			speed;
2085
2086	dev_vdbg(dwc->dev, "%s\n", __func__);
2087
2088	memset(&params, 0x00, sizeof(params));
2089
2090	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
2091	speed = reg & DWC3_DSTS_CONNECTSPD;
2092	dwc->speed = speed;
2093
2094	dwc3_update_ram_clk_sel(dwc, speed);
2095
2096	switch (speed) {
2097	case DWC3_DCFG_SUPERSPEED:
2098		/*
2099		 * WORKAROUND: DWC3 revisions <1.90a have an issue which
2100		 * would cause a missing USB3 Reset event.
2101		 *
2102		 * In such situations, we should force a USB3 Reset
2103		 * event by calling our dwc3_gadget_reset_interrupt()
2104		 * routine.
2105		 *
2106		 * Refers to:
2107		 *
2108		 * STAR#9000483510: RTL: SS : USB3 reset event may
2109		 * not be generated always when the link enters poll
2110		 */
2111		if (dwc->revision < DWC3_REVISION_190A)
2112			dwc3_gadget_reset_interrupt(dwc);
2113
2114		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
2115		dwc->gadget.ep0->maxpacket = 512;
2116		dwc->gadget.speed = USB_SPEED_SUPER;
2117		break;
2118	case DWC3_DCFG_HIGHSPEED:
2119		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2120		dwc->gadget.ep0->maxpacket = 64;
2121		dwc->gadget.speed = USB_SPEED_HIGH;
2122		break;
2123	case DWC3_DCFG_FULLSPEED2:
2124	case DWC3_DCFG_FULLSPEED1:
2125		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2126		dwc->gadget.ep0->maxpacket = 64;
2127		dwc->gadget.speed = USB_SPEED_FULL;
2128		break;
2129	case DWC3_DCFG_LOWSPEED:
2130		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(8);
2131		dwc->gadget.ep0->maxpacket = 8;
2132		dwc->gadget.speed = USB_SPEED_LOW;
2133		break;
2134	}
2135
2136	/* Recent versions support automatic phy suspend and don't need this */
2137	if (dwc->revision < DWC3_REVISION_194A) {
2138		/* Suspend unneeded PHY */
2139		dwc3_gadget_phy_suspend(dwc, dwc->gadget.speed);
2140	}
2141
2142	dep = dwc->eps[0];
2143	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true);
2144	if (ret) {
2145		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2146		return;
2147	}
2148
2149	dep = dwc->eps[1];
2150	ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL, true);
2151	if (ret) {
2152		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2153		return;
2154	}
2155
2156	/*
2157	 * Configure PHY via GUSB3PIPECTLn if required.
2158	 *
2159	 * Update GTXFIFOSIZn
2160	 *
2161	 * In both cases reset values should be sufficient.
2162	 */
2163}
2164
2165static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
2166{
2167	dev_vdbg(dwc->dev, "%s\n", __func__);
2168
2169	/*
2170	 * TODO take core out of low power mode when that's
2171	 * implemented.
2172	 */
2173
2174	dwc->gadget_driver->resume(&dwc->gadget);
2175}
2176
2177static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
2178		unsigned int evtinfo)
2179{
2180	enum dwc3_link_state	next = evtinfo & DWC3_LINK_STATE_MASK;
2181
2182	/*
2183	 * WORKAROUND: DWC3 Revisions <1.83a have an issue which, depending
2184	 * on the link partner, the USB session might do multiple entry/exit
2185	 * of low power states before a transfer takes place.
2186	 *
2187	 * Due to this problem, we might experience lower throughput. The
2188	 * suggested workaround is to disable DCTL[12:9] bits if we're
2189	 * transitioning from U1/U2 to U0 and enable those bits again
2190	 * after a transfer completes and there are no pending transfers
2191	 * on any of the enabled endpoints.
2192	 *
2193	 * This is the first half of that workaround.
2194	 *
2195	 * Refers to:
2196	 *
2197	 * STAR#9000446952: RTL: Device SS : if U1/U2 ->U0 takes >128us
2198	 * core send LGO_Ux entering U0
2199	 */
2200	if (dwc->revision < DWC3_REVISION_183A) {
2201		if (next == DWC3_LINK_STATE_U0) {
2202			u32	u1u2;
2203			u32	reg;
2204
2205			switch (dwc->link_state) {
2206			case DWC3_LINK_STATE_U1:
2207			case DWC3_LINK_STATE_U2:
2208				reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2209				u1u2 = reg & (DWC3_DCTL_INITU2ENA
2210						| DWC3_DCTL_ACCEPTU2ENA
2211						| DWC3_DCTL_INITU1ENA
2212						| DWC3_DCTL_ACCEPTU1ENA);
2213
2214				if (!dwc->u1u2)
2215					dwc->u1u2 = reg & u1u2;
2216
2217				reg &= ~u1u2;
2218
2219				dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2220				break;
2221			default:
2222				/* do nothing */
2223				break;
2224			}
2225		}
2226	}
2227
2228	dwc->link_state = next;
2229
2230	dev_vdbg(dwc->dev, "%s link %d\n", __func__, dwc->link_state);
2231}
2232
2233static void dwc3_gadget_interrupt(struct dwc3 *dwc,
2234		const struct dwc3_event_devt *event)
2235{
2236	switch (event->type) {
2237	case DWC3_DEVICE_EVENT_DISCONNECT:
2238		dwc3_gadget_disconnect_interrupt(dwc);
2239		break;
2240	case DWC3_DEVICE_EVENT_RESET:
2241		dwc3_gadget_reset_interrupt(dwc);
2242		break;
2243	case DWC3_DEVICE_EVENT_CONNECT_DONE:
2244		dwc3_gadget_conndone_interrupt(dwc);
2245		break;
2246	case DWC3_DEVICE_EVENT_WAKEUP:
2247		dwc3_gadget_wakeup_interrupt(dwc);
2248		break;
2249	case DWC3_DEVICE_EVENT_LINK_STATUS_CHANGE:
2250		dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);
2251		break;
2252	case DWC3_DEVICE_EVENT_EOPF:
2253		dev_vdbg(dwc->dev, "End of Periodic Frame\n");
2254		break;
2255	case DWC3_DEVICE_EVENT_SOF:
2256		dev_vdbg(dwc->dev, "Start of Periodic Frame\n");
2257		break;
2258	case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
2259		dev_vdbg(dwc->dev, "Erratic Error\n");
2260		break;
2261	case DWC3_DEVICE_EVENT_CMD_CMPL:
2262		dev_vdbg(dwc->dev, "Command Complete\n");
2263		break;
2264	case DWC3_DEVICE_EVENT_OVERFLOW:
2265		dev_vdbg(dwc->dev, "Overflow\n");
2266		break;
2267	default:
2268		dev_dbg(dwc->dev, "UNKNOWN IRQ %d\n", event->type);
2269	}
2270}
2271
2272static void dwc3_process_event_entry(struct dwc3 *dwc,
2273		const union dwc3_event *event)
2274{
2275	/* Endpoint IRQ, handle it and return early */
2276	if (event->type.is_devspec == 0) {
2277		/* depevt */
2278		return dwc3_endpoint_interrupt(dwc, &event->depevt);
2279	}
2280
2281	switch (event->type.type) {
2282	case DWC3_EVENT_TYPE_DEV:
2283		dwc3_gadget_interrupt(dwc, &event->devt);
2284		break;
2285	/* REVISIT what to do with Carkit and I2C events ? */
2286	default:
2287		dev_err(dwc->dev, "UNKNOWN IRQ type %d\n", event->raw);
2288	}
2289}
2290
2291static irqreturn_t dwc3_process_event_buf(struct dwc3 *dwc, u32 buf)
2292{
2293	struct dwc3_event_buffer *evt;
2294	int left;
2295	u32 count;
2296
2297	count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(buf));
2298	count &= DWC3_GEVNTCOUNT_MASK;
2299	if (!count)
2300		return IRQ_NONE;
2301
2302	evt = dwc->ev_buffs[buf];
2303	left = count;
2304
2305	while (left > 0) {
2306		union dwc3_event event;
2307
2308		event.raw = *(u32 *) (evt->buf + evt->lpos);
2309
2310		dwc3_process_event_entry(dwc, &event);
2311		/*
2312		 * XXX we wrap around correctly to the next entry as almost all
2313		 * entries are 4 bytes in size. There is one entry which has 12
2314		 * bytes which is a regular entry followed by 8 bytes data. ATM
2315		 * I don't know how things are organized if were get next to the
2316		 * a boundary so I worry about that once we try to handle that.
2317		 */
2318		evt->lpos = (evt->lpos + 4) % DWC3_EVENT_BUFFERS_SIZE;
2319		left -= 4;
2320
2321		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(buf), 4);
2322	}
2323
2324	return IRQ_HANDLED;
2325}
2326
2327static irqreturn_t dwc3_interrupt(int irq, void *_dwc)
2328{
2329	struct dwc3			*dwc = _dwc;
2330	int				i;
2331	irqreturn_t			ret = IRQ_NONE;
2332
2333	spin_lock(&dwc->lock);
2334
2335	for (i = 0; i < dwc->num_event_buffers; i++) {
2336		irqreturn_t status;
2337
2338		status = dwc3_process_event_buf(dwc, i);
2339		if (status == IRQ_HANDLED)
2340			ret = status;
2341	}
2342
2343	spin_unlock(&dwc->lock);
2344
2345	return ret;
2346}
2347
2348/**
2349 * dwc3_gadget_init - Initializes gadget related registers
2350 * @dwc: pointer to our controller context structure
2351 *
2352 * Returns 0 on success otherwise negative errno.
2353 */
2354int __devinit dwc3_gadget_init(struct dwc3 *dwc)
2355{
2356	u32					reg;
2357	int					ret;
2358	int					irq;
2359
2360	dwc->ctrl_req = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
2361			&dwc->ctrl_req_addr, GFP_KERNEL);
2362	if (!dwc->ctrl_req) {
2363		dev_err(dwc->dev, "failed to allocate ctrl request\n");
2364		ret = -ENOMEM;
2365		goto err0;
2366	}
2367
2368	dwc->ep0_trb = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
2369			&dwc->ep0_trb_addr, GFP_KERNEL);
2370	if (!dwc->ep0_trb) {
2371		dev_err(dwc->dev, "failed to allocate ep0 trb\n");
2372		ret = -ENOMEM;
2373		goto err1;
2374	}
2375
2376	dwc->setup_buf = kzalloc(DWC3_EP0_BOUNCE_SIZE, GFP_KERNEL);
2377	if (!dwc->setup_buf) {
2378		dev_err(dwc->dev, "failed to allocate setup buffer\n");
2379		ret = -ENOMEM;
2380		goto err2;
2381	}
2382
2383	dwc->ep0_bounce = dma_alloc_coherent(dwc->dev,
2384			DWC3_EP0_BOUNCE_SIZE, &dwc->ep0_bounce_addr,
2385			GFP_KERNEL);
2386	if (!dwc->ep0_bounce) {
2387		dev_err(dwc->dev, "failed to allocate ep0 bounce buffer\n");
2388		ret = -ENOMEM;
2389		goto err3;
2390	}
2391
2392	dev_set_name(&dwc->gadget.dev, "gadget");
2393
2394	dwc->gadget.ops			= &dwc3_gadget_ops;
2395	dwc->gadget.max_speed		= USB_SPEED_SUPER;
2396	dwc->gadget.speed		= USB_SPEED_UNKNOWN;
2397	dwc->gadget.dev.parent		= dwc->dev;
2398	dwc->gadget.sg_supported	= true;
2399
2400	dma_set_coherent_mask(&dwc->gadget.dev, dwc->dev->coherent_dma_mask);
2401
2402	dwc->gadget.dev.dma_parms	= dwc->dev->dma_parms;
2403	dwc->gadget.dev.dma_mask	= dwc->dev->dma_mask;
2404	dwc->gadget.dev.release		= dwc3_gadget_release;
2405	dwc->gadget.name		= "dwc3-gadget";
2406
2407	/*
2408	 * REVISIT: Here we should clear all pending IRQs to be
2409	 * sure we're starting from a well known location.
2410	 */
2411
2412	ret = dwc3_gadget_init_endpoints(dwc);
2413	if (ret)
2414		goto err4;
2415
2416	irq = platform_get_irq(to_platform_device(dwc->dev), 0);
2417
2418	ret = request_irq(irq, dwc3_interrupt, IRQF_SHARED,
2419			"dwc3", dwc);
2420	if (ret) {
2421		dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
2422				irq, ret);
2423		goto err5;
2424	}
2425
2426	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2427	reg |= DWC3_DCFG_LPM_CAP;
2428	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2429
2430	/* Enable all but Start and End of Frame IRQs */
2431	reg = (DWC3_DEVTEN_VNDRDEVTSTRCVEDEN |
2432			DWC3_DEVTEN_EVNTOVERFLOWEN |
2433			DWC3_DEVTEN_CMDCMPLTEN |
2434			DWC3_DEVTEN_ERRTICERREN |
2435			DWC3_DEVTEN_WKUPEVTEN |
2436			DWC3_DEVTEN_ULSTCNGEN |
2437			DWC3_DEVTEN_CONNECTDONEEN |
2438			DWC3_DEVTEN_USBRSTEN |
2439			DWC3_DEVTEN_DISCONNEVTEN);
2440	dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
2441
2442	/* Enable USB2 LPM and automatic phy suspend only on recent versions */
2443	if (dwc->revision >= DWC3_REVISION_194A) {
2444		reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2445		reg |= DWC3_DCFG_LPM_CAP;
2446		dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2447
2448		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2449		reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
2450
2451		/* TODO: This should be configurable */
2452		reg |= DWC3_DCTL_HIRD_THRES(28);
2453
2454		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2455
2456		dwc3_gadget_usb2_phy_suspend(dwc, false);
2457		dwc3_gadget_usb3_phy_suspend(dwc, false);
2458	}
2459
2460	ret = device_register(&dwc->gadget.dev);
2461	if (ret) {
2462		dev_err(dwc->dev, "failed to register gadget device\n");
2463		put_device(&dwc->gadget.dev);
2464		goto err6;
2465	}
2466
2467	ret = usb_add_gadget_udc(dwc->dev, &dwc->gadget);
2468	if (ret) {
2469		dev_err(dwc->dev, "failed to register udc\n");
2470		goto err7;
2471	}
2472
2473	return 0;
2474
2475err7:
2476	device_unregister(&dwc->gadget.dev);
2477
2478err6:
2479	dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
2480	free_irq(irq, dwc);
2481
2482err5:
2483	dwc3_gadget_free_endpoints(dwc);
2484
2485err4:
2486	dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
2487			dwc->ep0_bounce, dwc->ep0_bounce_addr);
2488
2489err3:
2490	kfree(dwc->setup_buf);
2491
2492err2:
2493	dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
2494			dwc->ep0_trb, dwc->ep0_trb_addr);
2495
2496err1:
2497	dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
2498			dwc->ctrl_req, dwc->ctrl_req_addr);
2499
2500err0:
2501	return ret;
2502}
2503
2504void dwc3_gadget_exit(struct dwc3 *dwc)
2505{
2506	int			irq;
2507
2508	usb_del_gadget_udc(&dwc->gadget);
2509	irq = platform_get_irq(to_platform_device(dwc->dev), 0);
2510
2511	dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
2512	free_irq(irq, dwc);
2513
2514	dwc3_gadget_free_endpoints(dwc);
2515
2516	dma_free_coherent(dwc->dev, DWC3_EP0_BOUNCE_SIZE,
2517			dwc->ep0_bounce, dwc->ep0_bounce_addr);
2518
2519	kfree(dwc->setup_buf);
2520
2521	dma_free_coherent(dwc->dev, sizeof(*dwc->ep0_trb),
2522			dwc->ep0_trb, dwc->ep0_trb_addr);
2523
2524	dma_free_coherent(dwc->dev, sizeof(*dwc->ctrl_req),
2525			dwc->ctrl_req, dwc->ctrl_req_addr);
2526
2527	device_unregister(&dwc->gadget.dev);
2528}
2529