1/*
2 * MUSB OTG driver peripheral support
3 *
4 * Copyright 2005 Mentor Graphics Corporation
5 * Copyright (C) 2005-2006 by Texas Instruments
6 * Copyright (C) 2006-2007 Nokia Corporation
7 * Copyright (C) 2009 MontaVista Software, Inc. <source@mvista.com>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * version 2 as published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
21 * 02110-1301 USA
22 *
23 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
26 * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
29 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
30 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 *
34 */
35
36#include <linux/kernel.h>
37#include <linux/list.h>
38#include <linux/timer.h>
39#include <linux/module.h>
40#include <linux/smp.h>
41#include <linux/spinlock.h>
42#include <linux/delay.h>
43#include <linux/dma-mapping.h>
44#include <linux/slab.h>
45
46#include "musb_core.h"
47
48
49/* ----------------------------------------------------------------------- */
50
51#define is_buffer_mapped(req) (is_dma_capable() && \
52					(req->map_state != UN_MAPPED))
53
54/* Maps the buffer to dma  */
55
56static inline void map_dma_buffer(struct musb_request *request,
57			struct musb *musb, struct musb_ep *musb_ep)
58{
59	int compatible = true;
60	struct dma_controller *dma = musb->dma_controller;
61
62	request->map_state = UN_MAPPED;
63
64	if (!is_dma_capable() || !musb_ep->dma)
65		return;
66
67	/* Check if DMA engine can handle this request.
68	 * DMA code must reject the USB request explicitly.
69	 * Default behaviour is to map the request.
70	 */
71	if (dma->is_compatible)
72		compatible = dma->is_compatible(musb_ep->dma,
73				musb_ep->packet_sz, request->request.buf,
74				request->request.length);
75	if (!compatible)
76		return;
77
78	if (request->request.dma == DMA_ADDR_INVALID) {
79		dma_addr_t dma_addr;
80		int ret;
81
82		dma_addr = dma_map_single(
83				musb->controller,
84				request->request.buf,
85				request->request.length,
86				request->tx
87					? DMA_TO_DEVICE
88					: DMA_FROM_DEVICE);
89		ret = dma_mapping_error(musb->controller, dma_addr);
90		if (ret)
91			return;
92
93		request->request.dma = dma_addr;
94		request->map_state = MUSB_MAPPED;
95	} else {
96		dma_sync_single_for_device(musb->controller,
97			request->request.dma,
98			request->request.length,
99			request->tx
100				? DMA_TO_DEVICE
101				: DMA_FROM_DEVICE);
102		request->map_state = PRE_MAPPED;
103	}
104}
105
106/* Unmap the buffer from dma and maps it back to cpu */
107static inline void unmap_dma_buffer(struct musb_request *request,
108				struct musb *musb)
109{
110	struct musb_ep *musb_ep = request->ep;
111
112	if (!is_buffer_mapped(request) || !musb_ep->dma)
113		return;
114
115	if (request->request.dma == DMA_ADDR_INVALID) {
116		dev_vdbg(musb->controller,
117				"not unmapping a never mapped buffer\n");
118		return;
119	}
120	if (request->map_state == MUSB_MAPPED) {
121		dma_unmap_single(musb->controller,
122			request->request.dma,
123			request->request.length,
124			request->tx
125				? DMA_TO_DEVICE
126				: DMA_FROM_DEVICE);
127		request->request.dma = DMA_ADDR_INVALID;
128	} else { /* PRE_MAPPED */
129		dma_sync_single_for_cpu(musb->controller,
130			request->request.dma,
131			request->request.length,
132			request->tx
133				? DMA_TO_DEVICE
134				: DMA_FROM_DEVICE);
135	}
136	request->map_state = UN_MAPPED;
137}
138
139/*
140 * Immediately complete a request.
141 *
142 * @param request the request to complete
143 * @param status the status to complete the request with
144 * Context: controller locked, IRQs blocked.
145 */
146void musb_g_giveback(
147	struct musb_ep		*ep,
148	struct usb_request	*request,
149	int			status)
150__releases(ep->musb->lock)
151__acquires(ep->musb->lock)
152{
153	struct musb_request	*req;
154	struct musb		*musb;
155	int			busy = ep->busy;
156
157	req = to_musb_request(request);
158
159	list_del(&req->list);
160	if (req->request.status == -EINPROGRESS)
161		req->request.status = status;
162	musb = req->musb;
163
164	ep->busy = 1;
165	spin_unlock(&musb->lock);
166
167	if (!dma_mapping_error(&musb->g.dev, request->dma))
168		unmap_dma_buffer(req, musb);
169
170	if (request->status == 0)
171		dev_dbg(musb->controller, "%s done request %p,  %d/%d\n",
172				ep->end_point.name, request,
173				req->request.actual, req->request.length);
174	else
175		dev_dbg(musb->controller, "%s request %p, %d/%d fault %d\n",
176				ep->end_point.name, request,
177				req->request.actual, req->request.length,
178				request->status);
179	usb_gadget_giveback_request(&req->ep->end_point, &req->request);
180	spin_lock(&musb->lock);
181	ep->busy = busy;
182}
183
184/* ----------------------------------------------------------------------- */
185
186/*
187 * Abort requests queued to an endpoint using the status. Synchronous.
188 * caller locked controller and blocked irqs, and selected this ep.
189 */
190static void nuke(struct musb_ep *ep, const int status)
191{
192	struct musb		*musb = ep->musb;
193	struct musb_request	*req = NULL;
194	void __iomem *epio = ep->musb->endpoints[ep->current_epnum].regs;
195
196	ep->busy = 1;
197
198	if (is_dma_capable() && ep->dma) {
199		struct dma_controller	*c = ep->musb->dma_controller;
200		int value;
201
202		if (ep->is_in) {
203			/*
204			 * The programming guide says that we must not clear
205			 * the DMAMODE bit before DMAENAB, so we only
206			 * clear it in the second write...
207			 */
208			musb_writew(epio, MUSB_TXCSR,
209				    MUSB_TXCSR_DMAMODE | MUSB_TXCSR_FLUSHFIFO);
210			musb_writew(epio, MUSB_TXCSR,
211					0 | MUSB_TXCSR_FLUSHFIFO);
212		} else {
213			musb_writew(epio, MUSB_RXCSR,
214					0 | MUSB_RXCSR_FLUSHFIFO);
215			musb_writew(epio, MUSB_RXCSR,
216					0 | MUSB_RXCSR_FLUSHFIFO);
217		}
218
219		value = c->channel_abort(ep->dma);
220		dev_dbg(musb->controller, "%s: abort DMA --> %d\n",
221				ep->name, value);
222		c->channel_release(ep->dma);
223		ep->dma = NULL;
224	}
225
226	while (!list_empty(&ep->req_list)) {
227		req = list_first_entry(&ep->req_list, struct musb_request, list);
228		musb_g_giveback(ep, &req->request, status);
229	}
230}
231
232/* ----------------------------------------------------------------------- */
233
234/* Data transfers - pure PIO, pure DMA, or mixed mode */
235
236/*
237 * This assumes the separate CPPI engine is responding to DMA requests
238 * from the usb core ... sequenced a bit differently from mentor dma.
239 */
240
241static inline int max_ep_writesize(struct musb *musb, struct musb_ep *ep)
242{
243	if (can_bulk_split(musb, ep->type))
244		return ep->hw_ep->max_packet_sz_tx;
245	else
246		return ep->packet_sz;
247}
248
249/*
250 * An endpoint is transmitting data. This can be called either from
251 * the IRQ routine or from ep.queue() to kickstart a request on an
252 * endpoint.
253 *
254 * Context: controller locked, IRQs blocked, endpoint selected
255 */
256static void txstate(struct musb *musb, struct musb_request *req)
257{
258	u8			epnum = req->epnum;
259	struct musb_ep		*musb_ep;
260	void __iomem		*epio = musb->endpoints[epnum].regs;
261	struct usb_request	*request;
262	u16			fifo_count = 0, csr;
263	int			use_dma = 0;
264
265	musb_ep = req->ep;
266
267	/* Check if EP is disabled */
268	if (!musb_ep->desc) {
269		dev_dbg(musb->controller, "ep:%s disabled - ignore request\n",
270						musb_ep->end_point.name);
271		return;
272	}
273
274	/* we shouldn't get here while DMA is active ... but we do ... */
275	if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) {
276		dev_dbg(musb->controller, "dma pending...\n");
277		return;
278	}
279
280	/* read TXCSR before */
281	csr = musb_readw(epio, MUSB_TXCSR);
282
283	request = &req->request;
284	fifo_count = min(max_ep_writesize(musb, musb_ep),
285			(int)(request->length - request->actual));
286
287	if (csr & MUSB_TXCSR_TXPKTRDY) {
288		dev_dbg(musb->controller, "%s old packet still ready , txcsr %03x\n",
289				musb_ep->end_point.name, csr);
290		return;
291	}
292
293	if (csr & MUSB_TXCSR_P_SENDSTALL) {
294		dev_dbg(musb->controller, "%s stalling, txcsr %03x\n",
295				musb_ep->end_point.name, csr);
296		return;
297	}
298
299	dev_dbg(musb->controller, "hw_ep%d, maxpacket %d, fifo count %d, txcsr %03x\n",
300			epnum, musb_ep->packet_sz, fifo_count,
301			csr);
302
303#ifndef	CONFIG_MUSB_PIO_ONLY
304	if (is_buffer_mapped(req)) {
305		struct dma_controller	*c = musb->dma_controller;
306		size_t request_size;
307
308		/* setup DMA, then program endpoint CSR */
309		request_size = min_t(size_t, request->length - request->actual,
310					musb_ep->dma->max_len);
311
312		use_dma = (request->dma != DMA_ADDR_INVALID && request_size);
313
314		/* MUSB_TXCSR_P_ISO is still set correctly */
315
316		if (musb_dma_inventra(musb) || musb_dma_ux500(musb)) {
317			if (request_size < musb_ep->packet_sz)
318				musb_ep->dma->desired_mode = 0;
319			else
320				musb_ep->dma->desired_mode = 1;
321
322			use_dma = use_dma && c->channel_program(
323					musb_ep->dma, musb_ep->packet_sz,
324					musb_ep->dma->desired_mode,
325					request->dma + request->actual, request_size);
326			if (use_dma) {
327				if (musb_ep->dma->desired_mode == 0) {
328					/*
329					 * We must not clear the DMAMODE bit
330					 * before the DMAENAB bit -- and the
331					 * latter doesn't always get cleared
332					 * before we get here...
333					 */
334					csr &= ~(MUSB_TXCSR_AUTOSET
335						| MUSB_TXCSR_DMAENAB);
336					musb_writew(epio, MUSB_TXCSR, csr
337						| MUSB_TXCSR_P_WZC_BITS);
338					csr &= ~MUSB_TXCSR_DMAMODE;
339					csr |= (MUSB_TXCSR_DMAENAB |
340							MUSB_TXCSR_MODE);
341					/* against programming guide */
342				} else {
343					csr |= (MUSB_TXCSR_DMAENAB
344							| MUSB_TXCSR_DMAMODE
345							| MUSB_TXCSR_MODE);
346					/*
347					 * Enable Autoset according to table
348					 * below
349					 * bulk_split hb_mult	Autoset_Enable
350					 *	0	0	Yes(Normal)
351					 *	0	>0	No(High BW ISO)
352					 *	1	0	Yes(HS bulk)
353					 *	1	>0	Yes(FS bulk)
354					 */
355					if (!musb_ep->hb_mult ||
356						(musb_ep->hb_mult &&
357						 can_bulk_split(musb,
358						    musb_ep->type)))
359						csr |= MUSB_TXCSR_AUTOSET;
360				}
361				csr &= ~MUSB_TXCSR_P_UNDERRUN;
362
363				musb_writew(epio, MUSB_TXCSR, csr);
364			}
365		}
366
367		if (is_cppi_enabled(musb)) {
368			/* program endpoint CSR first, then setup DMA */
369			csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
370			csr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_DMAMODE |
371				MUSB_TXCSR_MODE;
372			musb_writew(epio, MUSB_TXCSR, (MUSB_TXCSR_P_WZC_BITS &
373						~MUSB_TXCSR_P_UNDERRUN) | csr);
374
375			/* ensure writebuffer is empty */
376			csr = musb_readw(epio, MUSB_TXCSR);
377
378			/*
379			 * NOTE host side sets DMAENAB later than this; both are
380			 * OK since the transfer dma glue (between CPPI and
381			 * Mentor fifos) just tells CPPI it could start. Data
382			 * only moves to the USB TX fifo when both fifos are
383			 * ready.
384			 */
385			/*
386			 * "mode" is irrelevant here; handle terminating ZLPs
387			 * like PIO does, since the hardware RNDIS mode seems
388			 * unreliable except for the
389			 * last-packet-is-already-short case.
390			 */
391			use_dma = use_dma && c->channel_program(
392					musb_ep->dma, musb_ep->packet_sz,
393					0,
394					request->dma + request->actual,
395					request_size);
396			if (!use_dma) {
397				c->channel_release(musb_ep->dma);
398				musb_ep->dma = NULL;
399				csr &= ~MUSB_TXCSR_DMAENAB;
400				musb_writew(epio, MUSB_TXCSR, csr);
401				/* invariant: prequest->buf is non-null */
402			}
403		} else if (tusb_dma_omap(musb))
404			use_dma = use_dma && c->channel_program(
405					musb_ep->dma, musb_ep->packet_sz,
406					request->zero,
407					request->dma + request->actual,
408					request_size);
409	}
410#endif
411
412	if (!use_dma) {
413		/*
414		 * Unmap the dma buffer back to cpu if dma channel
415		 * programming fails
416		 */
417		unmap_dma_buffer(req, musb);
418
419		musb_write_fifo(musb_ep->hw_ep, fifo_count,
420				(u8 *) (request->buf + request->actual));
421		request->actual += fifo_count;
422		csr |= MUSB_TXCSR_TXPKTRDY;
423		csr &= ~MUSB_TXCSR_P_UNDERRUN;
424		musb_writew(epio, MUSB_TXCSR, csr);
425	}
426
427	/* host may already have the data when this message shows... */
428	dev_dbg(musb->controller, "%s TX/IN %s len %d/%d, txcsr %04x, fifo %d/%d\n",
429			musb_ep->end_point.name, use_dma ? "dma" : "pio",
430			request->actual, request->length,
431			musb_readw(epio, MUSB_TXCSR),
432			fifo_count,
433			musb_readw(epio, MUSB_TXMAXP));
434}
435
436/*
437 * FIFO state update (e.g. data ready).
438 * Called from IRQ,  with controller locked.
439 */
440void musb_g_tx(struct musb *musb, u8 epnum)
441{
442	u16			csr;
443	struct musb_request	*req;
444	struct usb_request	*request;
445	u8 __iomem		*mbase = musb->mregs;
446	struct musb_ep		*musb_ep = &musb->endpoints[epnum].ep_in;
447	void __iomem		*epio = musb->endpoints[epnum].regs;
448	struct dma_channel	*dma;
449
450	musb_ep_select(mbase, epnum);
451	req = next_request(musb_ep);
452	request = &req->request;
453
454	csr = musb_readw(epio, MUSB_TXCSR);
455	dev_dbg(musb->controller, "<== %s, txcsr %04x\n", musb_ep->end_point.name, csr);
456
457	dma = is_dma_capable() ? musb_ep->dma : NULL;
458
459	/*
460	 * REVISIT: for high bandwidth, MUSB_TXCSR_P_INCOMPTX
461	 * probably rates reporting as a host error.
462	 */
463	if (csr & MUSB_TXCSR_P_SENTSTALL) {
464		csr |=	MUSB_TXCSR_P_WZC_BITS;
465		csr &= ~MUSB_TXCSR_P_SENTSTALL;
466		musb_writew(epio, MUSB_TXCSR, csr);
467		return;
468	}
469
470	if (csr & MUSB_TXCSR_P_UNDERRUN) {
471		/* We NAKed, no big deal... little reason to care. */
472		csr |=	 MUSB_TXCSR_P_WZC_BITS;
473		csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
474		musb_writew(epio, MUSB_TXCSR, csr);
475		dev_vdbg(musb->controller, "underrun on ep%d, req %p\n",
476				epnum, request);
477	}
478
479	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
480		/*
481		 * SHOULD NOT HAPPEN... has with CPPI though, after
482		 * changing SENDSTALL (and other cases); harmless?
483		 */
484		dev_dbg(musb->controller, "%s dma still busy?\n", musb_ep->end_point.name);
485		return;
486	}
487
488	if (request) {
489		u8	is_dma = 0;
490		bool	short_packet = false;
491
492		if (dma && (csr & MUSB_TXCSR_DMAENAB)) {
493			is_dma = 1;
494			csr |= MUSB_TXCSR_P_WZC_BITS;
495			csr &= ~(MUSB_TXCSR_DMAENAB | MUSB_TXCSR_P_UNDERRUN |
496				 MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_AUTOSET);
497			musb_writew(epio, MUSB_TXCSR, csr);
498			/* Ensure writebuffer is empty. */
499			csr = musb_readw(epio, MUSB_TXCSR);
500			request->actual += musb_ep->dma->actual_len;
501			dev_dbg(musb->controller, "TXCSR%d %04x, DMA off, len %zu, req %p\n",
502				epnum, csr, musb_ep->dma->actual_len, request);
503		}
504
505		/*
506		 * First, maybe a terminating short packet. Some DMA
507		 * engines might handle this by themselves.
508		 */
509		if ((request->zero && request->length)
510			&& (request->length % musb_ep->packet_sz == 0)
511			&& (request->actual == request->length))
512				short_packet = true;
513
514		if ((musb_dma_inventra(musb) || musb_dma_ux500(musb)) &&
515			(is_dma && (!dma->desired_mode ||
516				(request->actual &
517					(musb_ep->packet_sz - 1)))))
518				short_packet = true;
519
520		if (short_packet) {
521			/*
522			 * On DMA completion, FIFO may not be
523			 * available yet...
524			 */
525			if (csr & MUSB_TXCSR_TXPKTRDY)
526				return;
527
528			dev_dbg(musb->controller, "sending zero pkt\n");
529			musb_writew(epio, MUSB_TXCSR, MUSB_TXCSR_MODE
530					| MUSB_TXCSR_TXPKTRDY);
531			request->zero = 0;
532		}
533
534		if (request->actual == request->length) {
535			musb_g_giveback(musb_ep, request, 0);
536			/*
537			 * In the giveback function the MUSB lock is
538			 * released and acquired after sometime. During
539			 * this time period the INDEX register could get
540			 * changed by the gadget_queue function especially
541			 * on SMP systems. Reselect the INDEX to be sure
542			 * we are reading/modifying the right registers
543			 */
544			musb_ep_select(mbase, epnum);
545			req = musb_ep->desc ? next_request(musb_ep) : NULL;
546			if (!req) {
547				dev_dbg(musb->controller, "%s idle now\n",
548					musb_ep->end_point.name);
549				return;
550			}
551		}
552
553		txstate(musb, req);
554	}
555}
556
557/* ------------------------------------------------------------ */
558
559/*
560 * Context: controller locked, IRQs blocked, endpoint selected
561 */
562static void rxstate(struct musb *musb, struct musb_request *req)
563{
564	const u8		epnum = req->epnum;
565	struct usb_request	*request = &req->request;
566	struct musb_ep		*musb_ep;
567	void __iomem		*epio = musb->endpoints[epnum].regs;
568	unsigned		len = 0;
569	u16			fifo_count;
570	u16			csr = musb_readw(epio, MUSB_RXCSR);
571	struct musb_hw_ep	*hw_ep = &musb->endpoints[epnum];
572	u8			use_mode_1;
573
574	if (hw_ep->is_shared_fifo)
575		musb_ep = &hw_ep->ep_in;
576	else
577		musb_ep = &hw_ep->ep_out;
578
579	fifo_count = musb_ep->packet_sz;
580
581	/* Check if EP is disabled */
582	if (!musb_ep->desc) {
583		dev_dbg(musb->controller, "ep:%s disabled - ignore request\n",
584						musb_ep->end_point.name);
585		return;
586	}
587
588	/* We shouldn't get here while DMA is active, but we do... */
589	if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) {
590		dev_dbg(musb->controller, "DMA pending...\n");
591		return;
592	}
593
594	if (csr & MUSB_RXCSR_P_SENDSTALL) {
595		dev_dbg(musb->controller, "%s stalling, RXCSR %04x\n",
596		    musb_ep->end_point.name, csr);
597		return;
598	}
599
600	if (is_cppi_enabled(musb) && is_buffer_mapped(req)) {
601		struct dma_controller	*c = musb->dma_controller;
602		struct dma_channel	*channel = musb_ep->dma;
603
604		/* NOTE:  CPPI won't actually stop advancing the DMA
605		 * queue after short packet transfers, so this is almost
606		 * always going to run as IRQ-per-packet DMA so that
607		 * faults will be handled correctly.
608		 */
609		if (c->channel_program(channel,
610				musb_ep->packet_sz,
611				!request->short_not_ok,
612				request->dma + request->actual,
613				request->length - request->actual)) {
614
615			/* make sure that if an rxpkt arrived after the irq,
616			 * the cppi engine will be ready to take it as soon
617			 * as DMA is enabled
618			 */
619			csr &= ~(MUSB_RXCSR_AUTOCLEAR
620					| MUSB_RXCSR_DMAMODE);
621			csr |= MUSB_RXCSR_DMAENAB | MUSB_RXCSR_P_WZC_BITS;
622			musb_writew(epio, MUSB_RXCSR, csr);
623			return;
624		}
625	}
626
627	if (csr & MUSB_RXCSR_RXPKTRDY) {
628		fifo_count = musb_readw(epio, MUSB_RXCOUNT);
629
630		/*
631		 * Enable Mode 1 on RX transfers only when short_not_ok flag
632		 * is set. Currently short_not_ok flag is set only from
633		 * file_storage and f_mass_storage drivers
634		 */
635
636		if (request->short_not_ok && fifo_count == musb_ep->packet_sz)
637			use_mode_1 = 1;
638		else
639			use_mode_1 = 0;
640
641		if (request->actual < request->length) {
642			if (!is_buffer_mapped(req))
643				goto buffer_aint_mapped;
644
645			if (musb_dma_inventra(musb)) {
646				struct dma_controller	*c;
647				struct dma_channel	*channel;
648				int			use_dma = 0;
649				unsigned int transfer_size;
650
651				c = musb->dma_controller;
652				channel = musb_ep->dma;
653
654	/* We use DMA Req mode 0 in rx_csr, and DMA controller operates in
655	 * mode 0 only. So we do not get endpoint interrupts due to DMA
656	 * completion. We only get interrupts from DMA controller.
657	 *
658	 * We could operate in DMA mode 1 if we knew the size of the tranfer
659	 * in advance. For mass storage class, request->length = what the host
660	 * sends, so that'd work.  But for pretty much everything else,
661	 * request->length is routinely more than what the host sends. For
662	 * most these gadgets, end of is signified either by a short packet,
663	 * or filling the last byte of the buffer.  (Sending extra data in
664	 * that last pckate should trigger an overflow fault.)  But in mode 1,
665	 * we don't get DMA completion interrupt for short packets.
666	 *
667	 * Theoretically, we could enable DMAReq irq (MUSB_RXCSR_DMAMODE = 1),
668	 * to get endpoint interrupt on every DMA req, but that didn't seem
669	 * to work reliably.
670	 *
671	 * REVISIT an updated g_file_storage can set req->short_not_ok, which
672	 * then becomes usable as a runtime "use mode 1" hint...
673	 */
674
675				/* Experimental: Mode1 works with mass storage use cases */
676				if (use_mode_1) {
677					csr |= MUSB_RXCSR_AUTOCLEAR;
678					musb_writew(epio, MUSB_RXCSR, csr);
679					csr |= MUSB_RXCSR_DMAENAB;
680					musb_writew(epio, MUSB_RXCSR, csr);
681
682					/*
683					 * this special sequence (enabling and then
684					 * disabling MUSB_RXCSR_DMAMODE) is required
685					 * to get DMAReq to activate
686					 */
687					musb_writew(epio, MUSB_RXCSR,
688						csr | MUSB_RXCSR_DMAMODE);
689					musb_writew(epio, MUSB_RXCSR, csr);
690
691					transfer_size = min_t(unsigned int,
692							request->length -
693							request->actual,
694							channel->max_len);
695					musb_ep->dma->desired_mode = 1;
696				} else {
697					if (!musb_ep->hb_mult &&
698						musb_ep->hw_ep->rx_double_buffered)
699						csr |= MUSB_RXCSR_AUTOCLEAR;
700					csr |= MUSB_RXCSR_DMAENAB;
701					musb_writew(epio, MUSB_RXCSR, csr);
702
703					transfer_size = min(request->length - request->actual,
704							(unsigned)fifo_count);
705					musb_ep->dma->desired_mode = 0;
706				}
707
708				use_dma = c->channel_program(
709						channel,
710						musb_ep->packet_sz,
711						channel->desired_mode,
712						request->dma
713						+ request->actual,
714						transfer_size);
715
716				if (use_dma)
717					return;
718			}
719
720			if ((musb_dma_ux500(musb)) &&
721				(request->actual < request->length)) {
722
723				struct dma_controller *c;
724				struct dma_channel *channel;
725				unsigned int transfer_size = 0;
726
727				c = musb->dma_controller;
728				channel = musb_ep->dma;
729
730				/* In case first packet is short */
731				if (fifo_count < musb_ep->packet_sz)
732					transfer_size = fifo_count;
733				else if (request->short_not_ok)
734					transfer_size =	min_t(unsigned int,
735							request->length -
736							request->actual,
737							channel->max_len);
738				else
739					transfer_size = min_t(unsigned int,
740							request->length -
741							request->actual,
742							(unsigned)fifo_count);
743
744				csr &= ~MUSB_RXCSR_DMAMODE;
745				csr |= (MUSB_RXCSR_DMAENAB |
746					MUSB_RXCSR_AUTOCLEAR);
747
748				musb_writew(epio, MUSB_RXCSR, csr);
749
750				if (transfer_size <= musb_ep->packet_sz) {
751					musb_ep->dma->desired_mode = 0;
752				} else {
753					musb_ep->dma->desired_mode = 1;
754					/* Mode must be set after DMAENAB */
755					csr |= MUSB_RXCSR_DMAMODE;
756					musb_writew(epio, MUSB_RXCSR, csr);
757				}
758
759				if (c->channel_program(channel,
760							musb_ep->packet_sz,
761							channel->desired_mode,
762							request->dma
763							+ request->actual,
764							transfer_size))
765
766					return;
767			}
768
769			len = request->length - request->actual;
770			dev_dbg(musb->controller, "%s OUT/RX pio fifo %d/%d, maxpacket %d\n",
771					musb_ep->end_point.name,
772					fifo_count, len,
773					musb_ep->packet_sz);
774
775			fifo_count = min_t(unsigned, len, fifo_count);
776
777			if (tusb_dma_omap(musb)) {
778				struct dma_controller *c = musb->dma_controller;
779				struct dma_channel *channel = musb_ep->dma;
780				u32 dma_addr = request->dma + request->actual;
781				int ret;
782
783				ret = c->channel_program(channel,
784						musb_ep->packet_sz,
785						channel->desired_mode,
786						dma_addr,
787						fifo_count);
788				if (ret)
789					return;
790			}
791
792			/*
793			 * Unmap the dma buffer back to cpu if dma channel
794			 * programming fails. This buffer is mapped if the
795			 * channel allocation is successful
796			 */
797			unmap_dma_buffer(req, musb);
798
799			/*
800			 * Clear DMAENAB and AUTOCLEAR for the
801			 * PIO mode transfer
802			 */
803			csr &= ~(MUSB_RXCSR_DMAENAB | MUSB_RXCSR_AUTOCLEAR);
804			musb_writew(epio, MUSB_RXCSR, csr);
805
806buffer_aint_mapped:
807			musb_read_fifo(musb_ep->hw_ep, fifo_count, (u8 *)
808					(request->buf + request->actual));
809			request->actual += fifo_count;
810
811			/* REVISIT if we left anything in the fifo, flush
812			 * it and report -EOVERFLOW
813			 */
814
815			/* ack the read! */
816			csr |= MUSB_RXCSR_P_WZC_BITS;
817			csr &= ~MUSB_RXCSR_RXPKTRDY;
818			musb_writew(epio, MUSB_RXCSR, csr);
819		}
820	}
821
822	/* reach the end or short packet detected */
823	if (request->actual == request->length ||
824	    fifo_count < musb_ep->packet_sz)
825		musb_g_giveback(musb_ep, request, 0);
826}
827
828/*
829 * Data ready for a request; called from IRQ
830 */
831void musb_g_rx(struct musb *musb, u8 epnum)
832{
833	u16			csr;
834	struct musb_request	*req;
835	struct usb_request	*request;
836	void __iomem		*mbase = musb->mregs;
837	struct musb_ep		*musb_ep;
838	void __iomem		*epio = musb->endpoints[epnum].regs;
839	struct dma_channel	*dma;
840	struct musb_hw_ep	*hw_ep = &musb->endpoints[epnum];
841
842	if (hw_ep->is_shared_fifo)
843		musb_ep = &hw_ep->ep_in;
844	else
845		musb_ep = &hw_ep->ep_out;
846
847	musb_ep_select(mbase, epnum);
848
849	req = next_request(musb_ep);
850	if (!req)
851		return;
852
853	request = &req->request;
854
855	csr = musb_readw(epio, MUSB_RXCSR);
856	dma = is_dma_capable() ? musb_ep->dma : NULL;
857
858	dev_dbg(musb->controller, "<== %s, rxcsr %04x%s %p\n", musb_ep->end_point.name,
859			csr, dma ? " (dma)" : "", request);
860
861	if (csr & MUSB_RXCSR_P_SENTSTALL) {
862		csr |= MUSB_RXCSR_P_WZC_BITS;
863		csr &= ~MUSB_RXCSR_P_SENTSTALL;
864		musb_writew(epio, MUSB_RXCSR, csr);
865		return;
866	}
867
868	if (csr & MUSB_RXCSR_P_OVERRUN) {
869		/* csr |= MUSB_RXCSR_P_WZC_BITS; */
870		csr &= ~MUSB_RXCSR_P_OVERRUN;
871		musb_writew(epio, MUSB_RXCSR, csr);
872
873		dev_dbg(musb->controller, "%s iso overrun on %p\n", musb_ep->name, request);
874		if (request->status == -EINPROGRESS)
875			request->status = -EOVERFLOW;
876	}
877	if (csr & MUSB_RXCSR_INCOMPRX) {
878		/* REVISIT not necessarily an error */
879		dev_dbg(musb->controller, "%s, incomprx\n", musb_ep->end_point.name);
880	}
881
882	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
883		/* "should not happen"; likely RXPKTRDY pending for DMA */
884		dev_dbg(musb->controller, "%s busy, csr %04x\n",
885			musb_ep->end_point.name, csr);
886		return;
887	}
888
889	if (dma && (csr & MUSB_RXCSR_DMAENAB)) {
890		csr &= ~(MUSB_RXCSR_AUTOCLEAR
891				| MUSB_RXCSR_DMAENAB
892				| MUSB_RXCSR_DMAMODE);
893		musb_writew(epio, MUSB_RXCSR,
894			MUSB_RXCSR_P_WZC_BITS | csr);
895
896		request->actual += musb_ep->dma->actual_len;
897
898		dev_dbg(musb->controller, "RXCSR%d %04x, dma off, %04x, len %zu, req %p\n",
899			epnum, csr,
900			musb_readw(epio, MUSB_RXCSR),
901			musb_ep->dma->actual_len, request);
902
903#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_TUSB_OMAP_DMA) || \
904	defined(CONFIG_USB_UX500_DMA)
905		/* Autoclear doesn't clear RxPktRdy for short packets */
906		if ((dma->desired_mode == 0 && !hw_ep->rx_double_buffered)
907				|| (dma->actual_len
908					& (musb_ep->packet_sz - 1))) {
909			/* ack the read! */
910			csr &= ~MUSB_RXCSR_RXPKTRDY;
911			musb_writew(epio, MUSB_RXCSR, csr);
912		}
913
914		/* incomplete, and not short? wait for next IN packet */
915		if ((request->actual < request->length)
916				&& (musb_ep->dma->actual_len
917					== musb_ep->packet_sz)) {
918			/* In double buffer case, continue to unload fifo if
919 			 * there is Rx packet in FIFO.
920 			 **/
921			csr = musb_readw(epio, MUSB_RXCSR);
922			if ((csr & MUSB_RXCSR_RXPKTRDY) &&
923				hw_ep->rx_double_buffered)
924				goto exit;
925			return;
926		}
927#endif
928		musb_g_giveback(musb_ep, request, 0);
929		/*
930		 * In the giveback function the MUSB lock is
931		 * released and acquired after sometime. During
932		 * this time period the INDEX register could get
933		 * changed by the gadget_queue function especially
934		 * on SMP systems. Reselect the INDEX to be sure
935		 * we are reading/modifying the right registers
936		 */
937		musb_ep_select(mbase, epnum);
938
939		req = next_request(musb_ep);
940		if (!req)
941			return;
942	}
943#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_TUSB_OMAP_DMA) || \
944	defined(CONFIG_USB_UX500_DMA)
945exit:
946#endif
947	/* Analyze request */
948	rxstate(musb, req);
949}
950
951/* ------------------------------------------------------------ */
952
953static int musb_gadget_enable(struct usb_ep *ep,
954			const struct usb_endpoint_descriptor *desc)
955{
956	unsigned long		flags;
957	struct musb_ep		*musb_ep;
958	struct musb_hw_ep	*hw_ep;
959	void __iomem		*regs;
960	struct musb		*musb;
961	void __iomem	*mbase;
962	u8		epnum;
963	u16		csr;
964	unsigned	tmp;
965	int		status = -EINVAL;
966
967	if (!ep || !desc)
968		return -EINVAL;
969
970	musb_ep = to_musb_ep(ep);
971	hw_ep = musb_ep->hw_ep;
972	regs = hw_ep->regs;
973	musb = musb_ep->musb;
974	mbase = musb->mregs;
975	epnum = musb_ep->current_epnum;
976
977	spin_lock_irqsave(&musb->lock, flags);
978
979	if (musb_ep->desc) {
980		status = -EBUSY;
981		goto fail;
982	}
983	musb_ep->type = usb_endpoint_type(desc);
984
985	/* check direction and (later) maxpacket size against endpoint */
986	if (usb_endpoint_num(desc) != epnum)
987		goto fail;
988
989	/* REVISIT this rules out high bandwidth periodic transfers */
990	tmp = usb_endpoint_maxp(desc);
991	if (tmp & ~0x07ff) {
992		int ok;
993
994		if (usb_endpoint_dir_in(desc))
995			ok = musb->hb_iso_tx;
996		else
997			ok = musb->hb_iso_rx;
998
999		if (!ok) {
1000			dev_dbg(musb->controller, "no support for high bandwidth ISO\n");
1001			goto fail;
1002		}
1003		musb_ep->hb_mult = (tmp >> 11) & 3;
1004	} else {
1005		musb_ep->hb_mult = 0;
1006	}
1007
1008	musb_ep->packet_sz = tmp & 0x7ff;
1009	tmp = musb_ep->packet_sz * (musb_ep->hb_mult + 1);
1010
1011	/* enable the interrupts for the endpoint, set the endpoint
1012	 * packet size (or fail), set the mode, clear the fifo
1013	 */
1014	musb_ep_select(mbase, epnum);
1015	if (usb_endpoint_dir_in(desc)) {
1016
1017		if (hw_ep->is_shared_fifo)
1018			musb_ep->is_in = 1;
1019		if (!musb_ep->is_in)
1020			goto fail;
1021
1022		if (tmp > hw_ep->max_packet_sz_tx) {
1023			dev_dbg(musb->controller, "packet size beyond hardware FIFO size\n");
1024			goto fail;
1025		}
1026
1027		musb->intrtxe |= (1 << epnum);
1028		musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe);
1029
1030		/* REVISIT if can_bulk_split(), use by updating "tmp";
1031		 * likewise high bandwidth periodic tx
1032		 */
1033		/* Set TXMAXP with the FIFO size of the endpoint
1034		 * to disable double buffering mode.
1035		 */
1036		if (musb->double_buffer_not_ok) {
1037			musb_writew(regs, MUSB_TXMAXP, hw_ep->max_packet_sz_tx);
1038		} else {
1039			if (can_bulk_split(musb, musb_ep->type))
1040				musb_ep->hb_mult = (hw_ep->max_packet_sz_tx /
1041							musb_ep->packet_sz) - 1;
1042			musb_writew(regs, MUSB_TXMAXP, musb_ep->packet_sz
1043					| (musb_ep->hb_mult << 11));
1044		}
1045
1046		csr = MUSB_TXCSR_MODE | MUSB_TXCSR_CLRDATATOG;
1047		if (musb_readw(regs, MUSB_TXCSR)
1048				& MUSB_TXCSR_FIFONOTEMPTY)
1049			csr |= MUSB_TXCSR_FLUSHFIFO;
1050		if (musb_ep->type == USB_ENDPOINT_XFER_ISOC)
1051			csr |= MUSB_TXCSR_P_ISO;
1052
1053		/* set twice in case of double buffering */
1054		musb_writew(regs, MUSB_TXCSR, csr);
1055		/* REVISIT may be inappropriate w/o FIFONOTEMPTY ... */
1056		musb_writew(regs, MUSB_TXCSR, csr);
1057
1058	} else {
1059
1060		if (hw_ep->is_shared_fifo)
1061			musb_ep->is_in = 0;
1062		if (musb_ep->is_in)
1063			goto fail;
1064
1065		if (tmp > hw_ep->max_packet_sz_rx) {
1066			dev_dbg(musb->controller, "packet size beyond hardware FIFO size\n");
1067			goto fail;
1068		}
1069
1070		musb->intrrxe |= (1 << epnum);
1071		musb_writew(mbase, MUSB_INTRRXE, musb->intrrxe);
1072
1073		/* REVISIT if can_bulk_combine() use by updating "tmp"
1074		 * likewise high bandwidth periodic rx
1075		 */
1076		/* Set RXMAXP with the FIFO size of the endpoint
1077		 * to disable double buffering mode.
1078		 */
1079		if (musb->double_buffer_not_ok)
1080			musb_writew(regs, MUSB_RXMAXP, hw_ep->max_packet_sz_tx);
1081		else
1082			musb_writew(regs, MUSB_RXMAXP, musb_ep->packet_sz
1083					| (musb_ep->hb_mult << 11));
1084
1085		/* force shared fifo to OUT-only mode */
1086		if (hw_ep->is_shared_fifo) {
1087			csr = musb_readw(regs, MUSB_TXCSR);
1088			csr &= ~(MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY);
1089			musb_writew(regs, MUSB_TXCSR, csr);
1090		}
1091
1092		csr = MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_CLRDATATOG;
1093		if (musb_ep->type == USB_ENDPOINT_XFER_ISOC)
1094			csr |= MUSB_RXCSR_P_ISO;
1095		else if (musb_ep->type == USB_ENDPOINT_XFER_INT)
1096			csr |= MUSB_RXCSR_DISNYET;
1097
1098		/* set twice in case of double buffering */
1099		musb_writew(regs, MUSB_RXCSR, csr);
1100		musb_writew(regs, MUSB_RXCSR, csr);
1101	}
1102
1103	/* NOTE:  all the I/O code _should_ work fine without DMA, in case
1104	 * for some reason you run out of channels here.
1105	 */
1106	if (is_dma_capable() && musb->dma_controller) {
1107		struct dma_controller	*c = musb->dma_controller;
1108
1109		musb_ep->dma = c->channel_alloc(c, hw_ep,
1110				(desc->bEndpointAddress & USB_DIR_IN));
1111	} else
1112		musb_ep->dma = NULL;
1113
1114	musb_ep->desc = desc;
1115	musb_ep->busy = 0;
1116	musb_ep->wedged = 0;
1117	status = 0;
1118
1119	pr_debug("%s periph: enabled %s for %s %s, %smaxpacket %d\n",
1120			musb_driver_name, musb_ep->end_point.name,
1121			({ char *s; switch (musb_ep->type) {
1122			case USB_ENDPOINT_XFER_BULK:	s = "bulk"; break;
1123			case USB_ENDPOINT_XFER_INT:	s = "int"; break;
1124			default:			s = "iso"; break;
1125			} s; }),
1126			musb_ep->is_in ? "IN" : "OUT",
1127			musb_ep->dma ? "dma, " : "",
1128			musb_ep->packet_sz);
1129
1130	schedule_work(&musb->irq_work);
1131
1132fail:
1133	spin_unlock_irqrestore(&musb->lock, flags);
1134	return status;
1135}
1136
1137/*
1138 * Disable an endpoint flushing all requests queued.
1139 */
1140static int musb_gadget_disable(struct usb_ep *ep)
1141{
1142	unsigned long	flags;
1143	struct musb	*musb;
1144	u8		epnum;
1145	struct musb_ep	*musb_ep;
1146	void __iomem	*epio;
1147	int		status = 0;
1148
1149	musb_ep = to_musb_ep(ep);
1150	musb = musb_ep->musb;
1151	epnum = musb_ep->current_epnum;
1152	epio = musb->endpoints[epnum].regs;
1153
1154	spin_lock_irqsave(&musb->lock, flags);
1155	musb_ep_select(musb->mregs, epnum);
1156
1157	/* zero the endpoint sizes */
1158	if (musb_ep->is_in) {
1159		musb->intrtxe &= ~(1 << epnum);
1160		musb_writew(musb->mregs, MUSB_INTRTXE, musb->intrtxe);
1161		musb_writew(epio, MUSB_TXMAXP, 0);
1162	} else {
1163		musb->intrrxe &= ~(1 << epnum);
1164		musb_writew(musb->mregs, MUSB_INTRRXE, musb->intrrxe);
1165		musb_writew(epio, MUSB_RXMAXP, 0);
1166	}
1167
1168	musb_ep->desc = NULL;
1169	musb_ep->end_point.desc = NULL;
1170
1171	/* abort all pending DMA and requests */
1172	nuke(musb_ep, -ESHUTDOWN);
1173
1174	schedule_work(&musb->irq_work);
1175
1176	spin_unlock_irqrestore(&(musb->lock), flags);
1177
1178	dev_dbg(musb->controller, "%s\n", musb_ep->end_point.name);
1179
1180	return status;
1181}
1182
1183/*
1184 * Allocate a request for an endpoint.
1185 * Reused by ep0 code.
1186 */
1187struct usb_request *musb_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1188{
1189	struct musb_ep		*musb_ep = to_musb_ep(ep);
1190	struct musb		*musb = musb_ep->musb;
1191	struct musb_request	*request = NULL;
1192
1193	request = kzalloc(sizeof *request, gfp_flags);
1194	if (!request) {
1195		dev_dbg(musb->controller, "not enough memory\n");
1196		return NULL;
1197	}
1198
1199	request->request.dma = DMA_ADDR_INVALID;
1200	request->epnum = musb_ep->current_epnum;
1201	request->ep = musb_ep;
1202
1203	return &request->request;
1204}
1205
1206/*
1207 * Free a request
1208 * Reused by ep0 code.
1209 */
1210void musb_free_request(struct usb_ep *ep, struct usb_request *req)
1211{
1212	kfree(to_musb_request(req));
1213}
1214
1215static LIST_HEAD(buffers);
1216
1217struct free_record {
1218	struct list_head	list;
1219	struct device		*dev;
1220	unsigned		bytes;
1221	dma_addr_t		dma;
1222};
1223
1224/*
1225 * Context: controller locked, IRQs blocked.
1226 */
1227void musb_ep_restart(struct musb *musb, struct musb_request *req)
1228{
1229	dev_dbg(musb->controller, "<== %s request %p len %u on hw_ep%d\n",
1230		req->tx ? "TX/IN" : "RX/OUT",
1231		&req->request, req->request.length, req->epnum);
1232
1233	musb_ep_select(musb->mregs, req->epnum);
1234	if (req->tx)
1235		txstate(musb, req);
1236	else
1237		rxstate(musb, req);
1238}
1239
1240static int musb_gadget_queue(struct usb_ep *ep, struct usb_request *req,
1241			gfp_t gfp_flags)
1242{
1243	struct musb_ep		*musb_ep;
1244	struct musb_request	*request;
1245	struct musb		*musb;
1246	int			status = 0;
1247	unsigned long		lockflags;
1248
1249	if (!ep || !req)
1250		return -EINVAL;
1251	if (!req->buf)
1252		return -ENODATA;
1253
1254	musb_ep = to_musb_ep(ep);
1255	musb = musb_ep->musb;
1256
1257	request = to_musb_request(req);
1258	request->musb = musb;
1259
1260	if (request->ep != musb_ep)
1261		return -EINVAL;
1262
1263	dev_dbg(musb->controller, "<== to %s request=%p\n", ep->name, req);
1264
1265	/* request is mine now... */
1266	request->request.actual = 0;
1267	request->request.status = -EINPROGRESS;
1268	request->epnum = musb_ep->current_epnum;
1269	request->tx = musb_ep->is_in;
1270
1271	map_dma_buffer(request, musb, musb_ep);
1272
1273	spin_lock_irqsave(&musb->lock, lockflags);
1274
1275	/* don't queue if the ep is down */
1276	if (!musb_ep->desc) {
1277		dev_dbg(musb->controller, "req %p queued to %s while ep %s\n",
1278				req, ep->name, "disabled");
1279		status = -ESHUTDOWN;
1280		unmap_dma_buffer(request, musb);
1281		goto unlock;
1282	}
1283
1284	/* add request to the list */
1285	list_add_tail(&request->list, &musb_ep->req_list);
1286
1287	/* it this is the head of the queue, start i/o ... */
1288	if (!musb_ep->busy && &request->list == musb_ep->req_list.next)
1289		musb_ep_restart(musb, request);
1290
1291unlock:
1292	spin_unlock_irqrestore(&musb->lock, lockflags);
1293	return status;
1294}
1295
1296static int musb_gadget_dequeue(struct usb_ep *ep, struct usb_request *request)
1297{
1298	struct musb_ep		*musb_ep = to_musb_ep(ep);
1299	struct musb_request	*req = to_musb_request(request);
1300	struct musb_request	*r;
1301	unsigned long		flags;
1302	int			status = 0;
1303	struct musb		*musb = musb_ep->musb;
1304
1305	if (!ep || !request || to_musb_request(request)->ep != musb_ep)
1306		return -EINVAL;
1307
1308	spin_lock_irqsave(&musb->lock, flags);
1309
1310	list_for_each_entry(r, &musb_ep->req_list, list) {
1311		if (r == req)
1312			break;
1313	}
1314	if (r != req) {
1315		dev_dbg(musb->controller, "request %p not queued to %s\n", request, ep->name);
1316		status = -EINVAL;
1317		goto done;
1318	}
1319
1320	/* if the hardware doesn't have the request, easy ... */
1321	if (musb_ep->req_list.next != &req->list || musb_ep->busy)
1322		musb_g_giveback(musb_ep, request, -ECONNRESET);
1323
1324	/* ... else abort the dma transfer ... */
1325	else if (is_dma_capable() && musb_ep->dma) {
1326		struct dma_controller	*c = musb->dma_controller;
1327
1328		musb_ep_select(musb->mregs, musb_ep->current_epnum);
1329		if (c->channel_abort)
1330			status = c->channel_abort(musb_ep->dma);
1331		else
1332			status = -EBUSY;
1333		if (status == 0)
1334			musb_g_giveback(musb_ep, request, -ECONNRESET);
1335	} else {
1336		/* NOTE: by sticking to easily tested hardware/driver states,
1337		 * we leave counting of in-flight packets imprecise.
1338		 */
1339		musb_g_giveback(musb_ep, request, -ECONNRESET);
1340	}
1341
1342done:
1343	spin_unlock_irqrestore(&musb->lock, flags);
1344	return status;
1345}
1346
1347/*
1348 * Set or clear the halt bit of an endpoint. A halted enpoint won't tx/rx any
1349 * data but will queue requests.
1350 *
1351 * exported to ep0 code
1352 */
1353static int musb_gadget_set_halt(struct usb_ep *ep, int value)
1354{
1355	struct musb_ep		*musb_ep = to_musb_ep(ep);
1356	u8			epnum = musb_ep->current_epnum;
1357	struct musb		*musb = musb_ep->musb;
1358	void __iomem		*epio = musb->endpoints[epnum].regs;
1359	void __iomem		*mbase;
1360	unsigned long		flags;
1361	u16			csr;
1362	struct musb_request	*request;
1363	int			status = 0;
1364
1365	if (!ep)
1366		return -EINVAL;
1367	mbase = musb->mregs;
1368
1369	spin_lock_irqsave(&musb->lock, flags);
1370
1371	if ((USB_ENDPOINT_XFER_ISOC == musb_ep->type)) {
1372		status = -EINVAL;
1373		goto done;
1374	}
1375
1376	musb_ep_select(mbase, epnum);
1377
1378	request = next_request(musb_ep);
1379	if (value) {
1380		if (request) {
1381			dev_dbg(musb->controller, "request in progress, cannot halt %s\n",
1382			    ep->name);
1383			status = -EAGAIN;
1384			goto done;
1385		}
1386		/* Cannot portably stall with non-empty FIFO */
1387		if (musb_ep->is_in) {
1388			csr = musb_readw(epio, MUSB_TXCSR);
1389			if (csr & MUSB_TXCSR_FIFONOTEMPTY) {
1390				dev_dbg(musb->controller, "FIFO busy, cannot halt %s\n", ep->name);
1391				status = -EAGAIN;
1392				goto done;
1393			}
1394		}
1395	} else
1396		musb_ep->wedged = 0;
1397
1398	/* set/clear the stall and toggle bits */
1399	dev_dbg(musb->controller, "%s: %s stall\n", ep->name, value ? "set" : "clear");
1400	if (musb_ep->is_in) {
1401		csr = musb_readw(epio, MUSB_TXCSR);
1402		csr |= MUSB_TXCSR_P_WZC_BITS
1403			| MUSB_TXCSR_CLRDATATOG;
1404		if (value)
1405			csr |= MUSB_TXCSR_P_SENDSTALL;
1406		else
1407			csr &= ~(MUSB_TXCSR_P_SENDSTALL
1408				| MUSB_TXCSR_P_SENTSTALL);
1409		csr &= ~MUSB_TXCSR_TXPKTRDY;
1410		musb_writew(epio, MUSB_TXCSR, csr);
1411	} else {
1412		csr = musb_readw(epio, MUSB_RXCSR);
1413		csr |= MUSB_RXCSR_P_WZC_BITS
1414			| MUSB_RXCSR_FLUSHFIFO
1415			| MUSB_RXCSR_CLRDATATOG;
1416		if (value)
1417			csr |= MUSB_RXCSR_P_SENDSTALL;
1418		else
1419			csr &= ~(MUSB_RXCSR_P_SENDSTALL
1420				| MUSB_RXCSR_P_SENTSTALL);
1421		musb_writew(epio, MUSB_RXCSR, csr);
1422	}
1423
1424	/* maybe start the first request in the queue */
1425	if (!musb_ep->busy && !value && request) {
1426		dev_dbg(musb->controller, "restarting the request\n");
1427		musb_ep_restart(musb, request);
1428	}
1429
1430done:
1431	spin_unlock_irqrestore(&musb->lock, flags);
1432	return status;
1433}
1434
1435/*
1436 * Sets the halt feature with the clear requests ignored
1437 */
1438static int musb_gadget_set_wedge(struct usb_ep *ep)
1439{
1440	struct musb_ep		*musb_ep = to_musb_ep(ep);
1441
1442	if (!ep)
1443		return -EINVAL;
1444
1445	musb_ep->wedged = 1;
1446
1447	return usb_ep_set_halt(ep);
1448}
1449
1450static int musb_gadget_fifo_status(struct usb_ep *ep)
1451{
1452	struct musb_ep		*musb_ep = to_musb_ep(ep);
1453	void __iomem		*epio = musb_ep->hw_ep->regs;
1454	int			retval = -EINVAL;
1455
1456	if (musb_ep->desc && !musb_ep->is_in) {
1457		struct musb		*musb = musb_ep->musb;
1458		int			epnum = musb_ep->current_epnum;
1459		void __iomem		*mbase = musb->mregs;
1460		unsigned long		flags;
1461
1462		spin_lock_irqsave(&musb->lock, flags);
1463
1464		musb_ep_select(mbase, epnum);
1465		/* FIXME return zero unless RXPKTRDY is set */
1466		retval = musb_readw(epio, MUSB_RXCOUNT);
1467
1468		spin_unlock_irqrestore(&musb->lock, flags);
1469	}
1470	return retval;
1471}
1472
1473static void musb_gadget_fifo_flush(struct usb_ep *ep)
1474{
1475	struct musb_ep	*musb_ep = to_musb_ep(ep);
1476	struct musb	*musb = musb_ep->musb;
1477	u8		epnum = musb_ep->current_epnum;
1478	void __iomem	*epio = musb->endpoints[epnum].regs;
1479	void __iomem	*mbase;
1480	unsigned long	flags;
1481	u16		csr;
1482
1483	mbase = musb->mregs;
1484
1485	spin_lock_irqsave(&musb->lock, flags);
1486	musb_ep_select(mbase, (u8) epnum);
1487
1488	/* disable interrupts */
1489	musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe & ~(1 << epnum));
1490
1491	if (musb_ep->is_in) {
1492		csr = musb_readw(epio, MUSB_TXCSR);
1493		if (csr & MUSB_TXCSR_FIFONOTEMPTY) {
1494			csr |= MUSB_TXCSR_FLUSHFIFO | MUSB_TXCSR_P_WZC_BITS;
1495			/*
1496			 * Setting both TXPKTRDY and FLUSHFIFO makes controller
1497			 * to interrupt current FIFO loading, but not flushing
1498			 * the already loaded ones.
1499			 */
1500			csr &= ~MUSB_TXCSR_TXPKTRDY;
1501			musb_writew(epio, MUSB_TXCSR, csr);
1502			/* REVISIT may be inappropriate w/o FIFONOTEMPTY ... */
1503			musb_writew(epio, MUSB_TXCSR, csr);
1504		}
1505	} else {
1506		csr = musb_readw(epio, MUSB_RXCSR);
1507		csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_P_WZC_BITS;
1508		musb_writew(epio, MUSB_RXCSR, csr);
1509		musb_writew(epio, MUSB_RXCSR, csr);
1510	}
1511
1512	/* re-enable interrupt */
1513	musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe);
1514	spin_unlock_irqrestore(&musb->lock, flags);
1515}
1516
1517static const struct usb_ep_ops musb_ep_ops = {
1518	.enable		= musb_gadget_enable,
1519	.disable	= musb_gadget_disable,
1520	.alloc_request	= musb_alloc_request,
1521	.free_request	= musb_free_request,
1522	.queue		= musb_gadget_queue,
1523	.dequeue	= musb_gadget_dequeue,
1524	.set_halt	= musb_gadget_set_halt,
1525	.set_wedge	= musb_gadget_set_wedge,
1526	.fifo_status	= musb_gadget_fifo_status,
1527	.fifo_flush	= musb_gadget_fifo_flush
1528};
1529
1530/* ----------------------------------------------------------------------- */
1531
1532static int musb_gadget_get_frame(struct usb_gadget *gadget)
1533{
1534	struct musb	*musb = gadget_to_musb(gadget);
1535
1536	return (int)musb_readw(musb->mregs, MUSB_FRAME);
1537}
1538
1539static int musb_gadget_wakeup(struct usb_gadget *gadget)
1540{
1541	struct musb	*musb = gadget_to_musb(gadget);
1542	void __iomem	*mregs = musb->mregs;
1543	unsigned long	flags;
1544	int		status = -EINVAL;
1545	u8		power, devctl;
1546	int		retries;
1547
1548	spin_lock_irqsave(&musb->lock, flags);
1549
1550	switch (musb->xceiv->otg->state) {
1551	case OTG_STATE_B_PERIPHERAL:
1552		/* NOTE:  OTG state machine doesn't include B_SUSPENDED;
1553		 * that's part of the standard usb 1.1 state machine, and
1554		 * doesn't affect OTG transitions.
1555		 */
1556		if (musb->may_wakeup && musb->is_suspended)
1557			break;
1558		goto done;
1559	case OTG_STATE_B_IDLE:
1560		/* Start SRP ... OTG not required. */
1561		devctl = musb_readb(mregs, MUSB_DEVCTL);
1562		dev_dbg(musb->controller, "Sending SRP: devctl: %02x\n", devctl);
1563		devctl |= MUSB_DEVCTL_SESSION;
1564		musb_writeb(mregs, MUSB_DEVCTL, devctl);
1565		devctl = musb_readb(mregs, MUSB_DEVCTL);
1566		retries = 100;
1567		while (!(devctl & MUSB_DEVCTL_SESSION)) {
1568			devctl = musb_readb(mregs, MUSB_DEVCTL);
1569			if (retries-- < 1)
1570				break;
1571		}
1572		retries = 10000;
1573		while (devctl & MUSB_DEVCTL_SESSION) {
1574			devctl = musb_readb(mregs, MUSB_DEVCTL);
1575			if (retries-- < 1)
1576				break;
1577		}
1578
1579		spin_unlock_irqrestore(&musb->lock, flags);
1580		otg_start_srp(musb->xceiv->otg);
1581		spin_lock_irqsave(&musb->lock, flags);
1582
1583		/* Block idling for at least 1s */
1584		musb_platform_try_idle(musb,
1585			jiffies + msecs_to_jiffies(1 * HZ));
1586
1587		status = 0;
1588		goto done;
1589	default:
1590		dev_dbg(musb->controller, "Unhandled wake: %s\n",
1591			usb_otg_state_string(musb->xceiv->otg->state));
1592		goto done;
1593	}
1594
1595	status = 0;
1596
1597	power = musb_readb(mregs, MUSB_POWER);
1598	power |= MUSB_POWER_RESUME;
1599	musb_writeb(mregs, MUSB_POWER, power);
1600	dev_dbg(musb->controller, "issue wakeup\n");
1601
1602	/* FIXME do this next chunk in a timer callback, no udelay */
1603	mdelay(2);
1604
1605	power = musb_readb(mregs, MUSB_POWER);
1606	power &= ~MUSB_POWER_RESUME;
1607	musb_writeb(mregs, MUSB_POWER, power);
1608done:
1609	spin_unlock_irqrestore(&musb->lock, flags);
1610	return status;
1611}
1612
1613static int
1614musb_gadget_set_self_powered(struct usb_gadget *gadget, int is_selfpowered)
1615{
1616	gadget->is_selfpowered = !!is_selfpowered;
1617	return 0;
1618}
1619
1620static void musb_pullup(struct musb *musb, int is_on)
1621{
1622	u8 power;
1623
1624	power = musb_readb(musb->mregs, MUSB_POWER);
1625	if (is_on)
1626		power |= MUSB_POWER_SOFTCONN;
1627	else
1628		power &= ~MUSB_POWER_SOFTCONN;
1629
1630	/* FIXME if on, HdrcStart; if off, HdrcStop */
1631
1632	dev_dbg(musb->controller, "gadget D+ pullup %s\n",
1633		is_on ? "on" : "off");
1634	musb_writeb(musb->mregs, MUSB_POWER, power);
1635}
1636
1637#if 0
1638static int musb_gadget_vbus_session(struct usb_gadget *gadget, int is_active)
1639{
1640	dev_dbg(musb->controller, "<= %s =>\n", __func__);
1641
1642	/*
1643	 * FIXME iff driver's softconnect flag is set (as it is during probe,
1644	 * though that can clear it), just musb_pullup().
1645	 */
1646
1647	return -EINVAL;
1648}
1649#endif
1650
1651static int musb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
1652{
1653	struct musb	*musb = gadget_to_musb(gadget);
1654
1655	if (!musb->xceiv->set_power)
1656		return -EOPNOTSUPP;
1657	return usb_phy_set_power(musb->xceiv, mA);
1658}
1659
1660static int musb_gadget_pullup(struct usb_gadget *gadget, int is_on)
1661{
1662	struct musb	*musb = gadget_to_musb(gadget);
1663	unsigned long	flags;
1664
1665	is_on = !!is_on;
1666
1667	pm_runtime_get_sync(musb->controller);
1668
1669	/* NOTE: this assumes we are sensing vbus; we'd rather
1670	 * not pullup unless the B-session is active.
1671	 */
1672	spin_lock_irqsave(&musb->lock, flags);
1673	if (is_on != musb->softconnect) {
1674		musb->softconnect = is_on;
1675		musb_pullup(musb, is_on);
1676	}
1677	spin_unlock_irqrestore(&musb->lock, flags);
1678
1679	pm_runtime_put(musb->controller);
1680
1681	return 0;
1682}
1683
1684#ifdef CONFIG_BLACKFIN
1685static struct usb_ep *musb_match_ep(struct usb_gadget *g,
1686		struct usb_endpoint_descriptor *desc,
1687		struct usb_ss_ep_comp_descriptor *ep_comp)
1688{
1689	struct usb_ep *ep = NULL;
1690
1691	switch (usb_endpoint_type(desc)) {
1692	case USB_ENDPOINT_XFER_ISOC:
1693	case USB_ENDPOINT_XFER_BULK:
1694		if (usb_endpoint_dir_in(desc))
1695			ep = gadget_find_ep_by_name(g, "ep5in");
1696		else
1697			ep = gadget_find_ep_by_name(g, "ep6out");
1698		break;
1699	case USB_ENDPOINT_XFER_INT:
1700		if (usb_endpoint_dir_in(desc))
1701			ep = gadget_find_ep_by_name(g, "ep1in");
1702		else
1703			ep = gadget_find_ep_by_name(g, "ep2out");
1704		break;
1705	default:
1706		break;
1707	}
1708
1709	if (ep && usb_gadget_ep_match_desc(g, ep, desc, ep_comp))
1710		return ep;
1711
1712	return NULL;
1713}
1714#else
1715#define musb_match_ep NULL
1716#endif
1717
1718static int musb_gadget_start(struct usb_gadget *g,
1719		struct usb_gadget_driver *driver);
1720static int musb_gadget_stop(struct usb_gadget *g);
1721
1722static const struct usb_gadget_ops musb_gadget_operations = {
1723	.get_frame		= musb_gadget_get_frame,
1724	.wakeup			= musb_gadget_wakeup,
1725	.set_selfpowered	= musb_gadget_set_self_powered,
1726	/* .vbus_session		= musb_gadget_vbus_session, */
1727	.vbus_draw		= musb_gadget_vbus_draw,
1728	.pullup			= musb_gadget_pullup,
1729	.udc_start		= musb_gadget_start,
1730	.udc_stop		= musb_gadget_stop,
1731	.match_ep		= musb_match_ep,
1732};
1733
1734/* ----------------------------------------------------------------------- */
1735
1736/* Registration */
1737
1738/* Only this registration code "knows" the rule (from USB standards)
1739 * about there being only one external upstream port.  It assumes
1740 * all peripheral ports are external...
1741 */
1742
1743static void
1744init_peripheral_ep(struct musb *musb, struct musb_ep *ep, u8 epnum, int is_in)
1745{
1746	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1747
1748	memset(ep, 0, sizeof *ep);
1749
1750	ep->current_epnum = epnum;
1751	ep->musb = musb;
1752	ep->hw_ep = hw_ep;
1753	ep->is_in = is_in;
1754
1755	INIT_LIST_HEAD(&ep->req_list);
1756
1757	sprintf(ep->name, "ep%d%s", epnum,
1758			(!epnum || hw_ep->is_shared_fifo) ? "" : (
1759				is_in ? "in" : "out"));
1760	ep->end_point.name = ep->name;
1761	INIT_LIST_HEAD(&ep->end_point.ep_list);
1762	if (!epnum) {
1763		usb_ep_set_maxpacket_limit(&ep->end_point, 64);
1764		ep->end_point.caps.type_control = true;
1765		ep->end_point.ops = &musb_g_ep0_ops;
1766		musb->g.ep0 = &ep->end_point;
1767	} else {
1768		if (is_in)
1769			usb_ep_set_maxpacket_limit(&ep->end_point, hw_ep->max_packet_sz_tx);
1770		else
1771			usb_ep_set_maxpacket_limit(&ep->end_point, hw_ep->max_packet_sz_rx);
1772		ep->end_point.caps.type_iso = true;
1773		ep->end_point.caps.type_bulk = true;
1774		ep->end_point.caps.type_int = true;
1775		ep->end_point.ops = &musb_ep_ops;
1776		list_add_tail(&ep->end_point.ep_list, &musb->g.ep_list);
1777	}
1778
1779	if (!epnum || hw_ep->is_shared_fifo) {
1780		ep->end_point.caps.dir_in = true;
1781		ep->end_point.caps.dir_out = true;
1782	} else if (is_in)
1783		ep->end_point.caps.dir_in = true;
1784	else
1785		ep->end_point.caps.dir_out = true;
1786}
1787
1788/*
1789 * Initialize the endpoints exposed to peripheral drivers, with backlinks
1790 * to the rest of the driver state.
1791 */
1792static inline void musb_g_init_endpoints(struct musb *musb)
1793{
1794	u8			epnum;
1795	struct musb_hw_ep	*hw_ep;
1796	unsigned		count = 0;
1797
1798	/* initialize endpoint list just once */
1799	INIT_LIST_HEAD(&(musb->g.ep_list));
1800
1801	for (epnum = 0, hw_ep = musb->endpoints;
1802			epnum < musb->nr_endpoints;
1803			epnum++, hw_ep++) {
1804		if (hw_ep->is_shared_fifo /* || !epnum */) {
1805			init_peripheral_ep(musb, &hw_ep->ep_in, epnum, 0);
1806			count++;
1807		} else {
1808			if (hw_ep->max_packet_sz_tx) {
1809				init_peripheral_ep(musb, &hw_ep->ep_in,
1810							epnum, 1);
1811				count++;
1812			}
1813			if (hw_ep->max_packet_sz_rx) {
1814				init_peripheral_ep(musb, &hw_ep->ep_out,
1815							epnum, 0);
1816				count++;
1817			}
1818		}
1819	}
1820}
1821
1822/* called once during driver setup to initialize and link into
1823 * the driver model; memory is zeroed.
1824 */
1825int musb_gadget_setup(struct musb *musb)
1826{
1827	int status;
1828
1829	/* REVISIT minor race:  if (erroneously) setting up two
1830	 * musb peripherals at the same time, only the bus lock
1831	 * is probably held.
1832	 */
1833
1834	musb->g.ops = &musb_gadget_operations;
1835	musb->g.max_speed = USB_SPEED_HIGH;
1836	musb->g.speed = USB_SPEED_UNKNOWN;
1837
1838	MUSB_DEV_MODE(musb);
1839	musb->xceiv->otg->default_a = 0;
1840	musb->xceiv->otg->state = OTG_STATE_B_IDLE;
1841
1842	/* this "gadget" abstracts/virtualizes the controller */
1843	musb->g.name = musb_driver_name;
1844#if IS_ENABLED(CONFIG_USB_MUSB_DUAL_ROLE)
1845	musb->g.is_otg = 1;
1846#elif IS_ENABLED(CONFIG_USB_MUSB_GADGET)
1847	musb->g.is_otg = 0;
1848#endif
1849
1850	musb_g_init_endpoints(musb);
1851
1852	musb->is_active = 0;
1853	musb_platform_try_idle(musb, 0);
1854
1855	status = usb_add_gadget_udc(musb->controller, &musb->g);
1856	if (status)
1857		goto err;
1858
1859	return 0;
1860err:
1861	musb->g.dev.parent = NULL;
1862	device_unregister(&musb->g.dev);
1863	return status;
1864}
1865
1866void musb_gadget_cleanup(struct musb *musb)
1867{
1868	if (musb->port_mode == MUSB_PORT_MODE_HOST)
1869		return;
1870	usb_del_gadget_udc(&musb->g);
1871}
1872
1873/*
1874 * Register the gadget driver. Used by gadget drivers when
1875 * registering themselves with the controller.
1876 *
1877 * -EINVAL something went wrong (not driver)
1878 * -EBUSY another gadget is already using the controller
1879 * -ENOMEM no memory to perform the operation
1880 *
1881 * @param driver the gadget driver
1882 * @return <0 if error, 0 if everything is fine
1883 */
1884static int musb_gadget_start(struct usb_gadget *g,
1885		struct usb_gadget_driver *driver)
1886{
1887	struct musb		*musb = gadget_to_musb(g);
1888	struct usb_otg		*otg = musb->xceiv->otg;
1889	unsigned long		flags;
1890	int			retval = 0;
1891
1892	if (driver->max_speed < USB_SPEED_HIGH) {
1893		retval = -EINVAL;
1894		goto err;
1895	}
1896
1897	pm_runtime_get_sync(musb->controller);
1898
1899	musb->softconnect = 0;
1900	musb->gadget_driver = driver;
1901
1902	spin_lock_irqsave(&musb->lock, flags);
1903	musb->is_active = 1;
1904
1905	otg_set_peripheral(otg, &musb->g);
1906	musb->xceiv->otg->state = OTG_STATE_B_IDLE;
1907	spin_unlock_irqrestore(&musb->lock, flags);
1908
1909	musb_start(musb);
1910
1911	/* REVISIT:  funcall to other code, which also
1912	 * handles power budgeting ... this way also
1913	 * ensures HdrcStart is indirectly called.
1914	 */
1915	if (musb->xceiv->last_event == USB_EVENT_ID)
1916		musb_platform_set_vbus(musb, 1);
1917
1918	if (musb->xceiv->last_event == USB_EVENT_NONE)
1919		pm_runtime_put(musb->controller);
1920
1921	return 0;
1922
1923err:
1924	return retval;
1925}
1926
1927/*
1928 * Unregister the gadget driver. Used by gadget drivers when
1929 * unregistering themselves from the controller.
1930 *
1931 * @param driver the gadget driver to unregister
1932 */
1933static int musb_gadget_stop(struct usb_gadget *g)
1934{
1935	struct musb	*musb = gadget_to_musb(g);
1936	unsigned long	flags;
1937
1938	if (musb->xceiv->last_event == USB_EVENT_NONE)
1939		pm_runtime_get_sync(musb->controller);
1940
1941	/*
1942	 * REVISIT always use otg_set_peripheral() here too;
1943	 * this needs to shut down the OTG engine.
1944	 */
1945
1946	spin_lock_irqsave(&musb->lock, flags);
1947
1948	musb_hnp_stop(musb);
1949
1950	(void) musb_gadget_vbus_draw(&musb->g, 0);
1951
1952	musb->xceiv->otg->state = OTG_STATE_UNDEFINED;
1953	musb_stop(musb);
1954	otg_set_peripheral(musb->xceiv->otg, NULL);
1955
1956	musb->is_active = 0;
1957	musb->gadget_driver = NULL;
1958	musb_platform_try_idle(musb, 0);
1959	spin_unlock_irqrestore(&musb->lock, flags);
1960
1961	/*
1962	 * FIXME we need to be able to register another
1963	 * gadget driver here and have everything work;
1964	 * that currently misbehaves.
1965	 */
1966
1967	pm_runtime_put(musb->controller);
1968
1969	return 0;
1970}
1971
1972/* ----------------------------------------------------------------------- */
1973
1974/* lifecycle operations called through plat_uds.c */
1975
1976void musb_g_resume(struct musb *musb)
1977{
1978	musb->is_suspended = 0;
1979	switch (musb->xceiv->otg->state) {
1980	case OTG_STATE_B_IDLE:
1981		break;
1982	case OTG_STATE_B_WAIT_ACON:
1983	case OTG_STATE_B_PERIPHERAL:
1984		musb->is_active = 1;
1985		if (musb->gadget_driver && musb->gadget_driver->resume) {
1986			spin_unlock(&musb->lock);
1987			musb->gadget_driver->resume(&musb->g);
1988			spin_lock(&musb->lock);
1989		}
1990		break;
1991	default:
1992		WARNING("unhandled RESUME transition (%s)\n",
1993				usb_otg_state_string(musb->xceiv->otg->state));
1994	}
1995}
1996
1997/* called when SOF packets stop for 3+ msec */
1998void musb_g_suspend(struct musb *musb)
1999{
2000	u8	devctl;
2001
2002	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
2003	dev_dbg(musb->controller, "devctl %02x\n", devctl);
2004
2005	switch (musb->xceiv->otg->state) {
2006	case OTG_STATE_B_IDLE:
2007		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
2008			musb->xceiv->otg->state = OTG_STATE_B_PERIPHERAL;
2009		break;
2010	case OTG_STATE_B_PERIPHERAL:
2011		musb->is_suspended = 1;
2012		if (musb->gadget_driver && musb->gadget_driver->suspend) {
2013			spin_unlock(&musb->lock);
2014			musb->gadget_driver->suspend(&musb->g);
2015			spin_lock(&musb->lock);
2016		}
2017		break;
2018	default:
2019		/* REVISIT if B_HOST, clear DEVCTL.HOSTREQ;
2020		 * A_PERIPHERAL may need care too
2021		 */
2022		WARNING("unhandled SUSPEND transition (%s)\n",
2023				usb_otg_state_string(musb->xceiv->otg->state));
2024	}
2025}
2026
2027/* Called during SRP */
2028void musb_g_wakeup(struct musb *musb)
2029{
2030	musb_gadget_wakeup(&musb->g);
2031}
2032
2033/* called when VBUS drops below session threshold, and in other cases */
2034void musb_g_disconnect(struct musb *musb)
2035{
2036	void __iomem	*mregs = musb->mregs;
2037	u8	devctl = musb_readb(mregs, MUSB_DEVCTL);
2038
2039	dev_dbg(musb->controller, "devctl %02x\n", devctl);
2040
2041	/* clear HR */
2042	musb_writeb(mregs, MUSB_DEVCTL, devctl & MUSB_DEVCTL_SESSION);
2043
2044	/* don't draw vbus until new b-default session */
2045	(void) musb_gadget_vbus_draw(&musb->g, 0);
2046
2047	musb->g.speed = USB_SPEED_UNKNOWN;
2048	if (musb->gadget_driver && musb->gadget_driver->disconnect) {
2049		spin_unlock(&musb->lock);
2050		musb->gadget_driver->disconnect(&musb->g);
2051		spin_lock(&musb->lock);
2052	}
2053
2054	switch (musb->xceiv->otg->state) {
2055	default:
2056		dev_dbg(musb->controller, "Unhandled disconnect %s, setting a_idle\n",
2057			usb_otg_state_string(musb->xceiv->otg->state));
2058		musb->xceiv->otg->state = OTG_STATE_A_IDLE;
2059		MUSB_HST_MODE(musb);
2060		break;
2061	case OTG_STATE_A_PERIPHERAL:
2062		musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
2063		MUSB_HST_MODE(musb);
2064		break;
2065	case OTG_STATE_B_WAIT_ACON:
2066	case OTG_STATE_B_HOST:
2067	case OTG_STATE_B_PERIPHERAL:
2068	case OTG_STATE_B_IDLE:
2069		musb->xceiv->otg->state = OTG_STATE_B_IDLE;
2070		break;
2071	case OTG_STATE_B_SRP_INIT:
2072		break;
2073	}
2074
2075	musb->is_active = 0;
2076}
2077
2078void musb_g_reset(struct musb *musb)
2079__releases(musb->lock)
2080__acquires(musb->lock)
2081{
2082	void __iomem	*mbase = musb->mregs;
2083	u8		devctl = musb_readb(mbase, MUSB_DEVCTL);
2084	u8		power;
2085
2086	dev_dbg(musb->controller, "<== %s driver '%s'\n",
2087			(devctl & MUSB_DEVCTL_BDEVICE)
2088				? "B-Device" : "A-Device",
2089			musb->gadget_driver
2090				? musb->gadget_driver->driver.name
2091				: NULL
2092			);
2093
2094	/* report reset, if we didn't already (flushing EP state) */
2095	if (musb->gadget_driver && musb->g.speed != USB_SPEED_UNKNOWN) {
2096		spin_unlock(&musb->lock);
2097		usb_gadget_udc_reset(&musb->g, musb->gadget_driver);
2098		spin_lock(&musb->lock);
2099	}
2100
2101	/* clear HR */
2102	else if (devctl & MUSB_DEVCTL_HR)
2103		musb_writeb(mbase, MUSB_DEVCTL, MUSB_DEVCTL_SESSION);
2104
2105
2106	/* what speed did we negotiate? */
2107	power = musb_readb(mbase, MUSB_POWER);
2108	musb->g.speed = (power & MUSB_POWER_HSMODE)
2109			? USB_SPEED_HIGH : USB_SPEED_FULL;
2110
2111	/* start in USB_STATE_DEFAULT */
2112	musb->is_active = 1;
2113	musb->is_suspended = 0;
2114	MUSB_DEV_MODE(musb);
2115	musb->address = 0;
2116	musb->ep0_state = MUSB_EP0_STAGE_SETUP;
2117
2118	musb->may_wakeup = 0;
2119	musb->g.b_hnp_enable = 0;
2120	musb->g.a_alt_hnp_support = 0;
2121	musb->g.a_hnp_support = 0;
2122	musb->g.quirk_zlp_not_supp = 1;
2123
2124	/* Normal reset, as B-Device;
2125	 * or else after HNP, as A-Device
2126	 */
2127	if (!musb->g.is_otg) {
2128		/* USB device controllers that are not OTG compatible
2129		 * may not have DEVCTL register in silicon.
2130		 * In that case, do not rely on devctl for setting
2131		 * peripheral mode.
2132		 */
2133		musb->xceiv->otg->state = OTG_STATE_B_PERIPHERAL;
2134		musb->g.is_a_peripheral = 0;
2135	} else if (devctl & MUSB_DEVCTL_BDEVICE) {
2136		musb->xceiv->otg->state = OTG_STATE_B_PERIPHERAL;
2137		musb->g.is_a_peripheral = 0;
2138	} else {
2139		musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
2140		musb->g.is_a_peripheral = 1;
2141	}
2142
2143	/* start with default limits on VBUS power draw */
2144	(void) musb_gadget_vbus_draw(&musb->g, 8);
2145}
2146