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