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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 #include "musb_trace.h"
48 
49 
50 /* ----------------------------------------------------------------------- */
51 
52 #define is_buffer_mapped(req) (is_dma_capable() && \
53 					(req->map_state != UN_MAPPED))
54 
55 /* Maps the buffer to dma  */
56 
map_dma_buffer(struct musb_request * request,struct musb * musb,struct musb_ep * musb_ep)57 static inline void map_dma_buffer(struct musb_request *request,
58 			struct musb *musb, struct musb_ep *musb_ep)
59 {
60 	int compatible = true;
61 	struct dma_controller *dma = musb->dma_controller;
62 
63 	request->map_state = UN_MAPPED;
64 
65 	if (!is_dma_capable() || !musb_ep->dma)
66 		return;
67 
68 	/* Check if DMA engine can handle this request.
69 	 * DMA code must reject the USB request explicitly.
70 	 * Default behaviour is to map the request.
71 	 */
72 	if (dma->is_compatible)
73 		compatible = dma->is_compatible(musb_ep->dma,
74 				musb_ep->packet_sz, request->request.buf,
75 				request->request.length);
76 	if (!compatible)
77 		return;
78 
79 	if (request->request.dma == DMA_ADDR_INVALID) {
80 		dma_addr_t dma_addr;
81 		int ret;
82 
83 		dma_addr = dma_map_single(
84 				musb->controller,
85 				request->request.buf,
86 				request->request.length,
87 				request->tx
88 					? DMA_TO_DEVICE
89 					: DMA_FROM_DEVICE);
90 		ret = dma_mapping_error(musb->controller, dma_addr);
91 		if (ret)
92 			return;
93 
94 		request->request.dma = dma_addr;
95 		request->map_state = MUSB_MAPPED;
96 	} else {
97 		dma_sync_single_for_device(musb->controller,
98 			request->request.dma,
99 			request->request.length,
100 			request->tx
101 				? DMA_TO_DEVICE
102 				: DMA_FROM_DEVICE);
103 		request->map_state = PRE_MAPPED;
104 	}
105 }
106 
107 /* Unmap the buffer from dma and maps it back to cpu */
unmap_dma_buffer(struct musb_request * request,struct musb * musb)108 static inline void unmap_dma_buffer(struct musb_request *request,
109 				struct musb *musb)
110 {
111 	struct musb_ep *musb_ep = request->ep;
112 
113 	if (!is_buffer_mapped(request) || !musb_ep->dma)
114 		return;
115 
116 	if (request->request.dma == DMA_ADDR_INVALID) {
117 		dev_vdbg(musb->controller,
118 				"not unmapping a never mapped buffer\n");
119 		return;
120 	}
121 	if (request->map_state == MUSB_MAPPED) {
122 		dma_unmap_single(musb->controller,
123 			request->request.dma,
124 			request->request.length,
125 			request->tx
126 				? DMA_TO_DEVICE
127 				: DMA_FROM_DEVICE);
128 		request->request.dma = DMA_ADDR_INVALID;
129 	} else { /* PRE_MAPPED */
130 		dma_sync_single_for_cpu(musb->controller,
131 			request->request.dma,
132 			request->request.length,
133 			request->tx
134 				? DMA_TO_DEVICE
135 				: DMA_FROM_DEVICE);
136 	}
137 	request->map_state = UN_MAPPED;
138 }
139 
140 /*
141  * Immediately complete a request.
142  *
143  * @param request the request to complete
144  * @param status the status to complete the request with
145  * Context: controller locked, IRQs blocked.
146  */
musb_g_giveback(struct musb_ep * ep,struct usb_request * request,int status)147 void musb_g_giveback(
148 	struct musb_ep		*ep,
149 	struct usb_request	*request,
150 	int			status)
151 __releases(ep->musb->lock)
152 __acquires(ep->musb->lock)
153 {
154 	struct musb_request	*req;
155 	struct musb		*musb;
156 	int			busy = ep->busy;
157 
158 	req = to_musb_request(request);
159 
160 	list_del(&req->list);
161 	if (req->request.status == -EINPROGRESS)
162 		req->request.status = status;
163 	musb = req->musb;
164 
165 	ep->busy = 1;
166 	spin_unlock(&musb->lock);
167 
168 	if (!dma_mapping_error(&musb->g.dev, request->dma))
169 		unmap_dma_buffer(req, musb);
170 
171 	trace_musb_req_gb(req);
172 	usb_gadget_giveback_request(&req->ep->end_point, &req->request);
173 	spin_lock(&musb->lock);
174 	ep->busy = busy;
175 }
176 
177 /* ----------------------------------------------------------------------- */
178 
179 /*
180  * Abort requests queued to an endpoint using the status. Synchronous.
181  * caller locked controller and blocked irqs, and selected this ep.
182  */
nuke(struct musb_ep * ep,const int status)183 static void nuke(struct musb_ep *ep, const int status)
184 {
185 	struct musb		*musb = ep->musb;
186 	struct musb_request	*req = NULL;
187 	void __iomem *epio = ep->musb->endpoints[ep->current_epnum].regs;
188 
189 	ep->busy = 1;
190 
191 	if (is_dma_capable() && ep->dma) {
192 		struct dma_controller	*c = ep->musb->dma_controller;
193 		int value;
194 
195 		if (ep->is_in) {
196 			/*
197 			 * The programming guide says that we must not clear
198 			 * the DMAMODE bit before DMAENAB, so we only
199 			 * clear it in the second write...
200 			 */
201 			musb_writew(epio, MUSB_TXCSR,
202 				    MUSB_TXCSR_DMAMODE | MUSB_TXCSR_FLUSHFIFO);
203 			musb_writew(epio, MUSB_TXCSR,
204 					0 | MUSB_TXCSR_FLUSHFIFO);
205 		} else {
206 			musb_writew(epio, MUSB_RXCSR,
207 					0 | MUSB_RXCSR_FLUSHFIFO);
208 			musb_writew(epio, MUSB_RXCSR,
209 					0 | MUSB_RXCSR_FLUSHFIFO);
210 		}
211 
212 		value = c->channel_abort(ep->dma);
213 		musb_dbg(musb, "%s: abort DMA --> %d", ep->name, value);
214 		c->channel_release(ep->dma);
215 		ep->dma = NULL;
216 	}
217 
218 	while (!list_empty(&ep->req_list)) {
219 		req = list_first_entry(&ep->req_list, struct musb_request, list);
220 		musb_g_giveback(ep, &req->request, status);
221 	}
222 }
223 
224 /* ----------------------------------------------------------------------- */
225 
226 /* Data transfers - pure PIO, pure DMA, or mixed mode */
227 
228 /*
229  * This assumes the separate CPPI engine is responding to DMA requests
230  * from the usb core ... sequenced a bit differently from mentor dma.
231  */
232 
max_ep_writesize(struct musb * musb,struct musb_ep * ep)233 static inline int max_ep_writesize(struct musb *musb, struct musb_ep *ep)
234 {
235 	if (can_bulk_split(musb, ep->type))
236 		return ep->hw_ep->max_packet_sz_tx;
237 	else
238 		return ep->packet_sz;
239 }
240 
241 /*
242  * An endpoint is transmitting data. This can be called either from
243  * the IRQ routine or from ep.queue() to kickstart a request on an
244  * endpoint.
245  *
246  * Context: controller locked, IRQs blocked, endpoint selected
247  */
txstate(struct musb * musb,struct musb_request * req)248 static void txstate(struct musb *musb, struct musb_request *req)
249 {
250 	u8			epnum = req->epnum;
251 	struct musb_ep		*musb_ep;
252 	void __iomem		*epio = musb->endpoints[epnum].regs;
253 	struct usb_request	*request;
254 	u16			fifo_count = 0, csr;
255 	int			use_dma = 0;
256 
257 	musb_ep = req->ep;
258 
259 	/* Check if EP is disabled */
260 	if (!musb_ep->desc) {
261 		musb_dbg(musb, "ep:%s disabled - ignore request",
262 						musb_ep->end_point.name);
263 		return;
264 	}
265 
266 	/* we shouldn't get here while DMA is active ... but we do ... */
267 	if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) {
268 		musb_dbg(musb, "dma pending...");
269 		return;
270 	}
271 
272 	/* read TXCSR before */
273 	csr = musb_readw(epio, MUSB_TXCSR);
274 
275 	request = &req->request;
276 	fifo_count = min(max_ep_writesize(musb, musb_ep),
277 			(int)(request->length - request->actual));
278 
279 	if (csr & MUSB_TXCSR_TXPKTRDY) {
280 		musb_dbg(musb, "%s old packet still ready , txcsr %03x",
281 				musb_ep->end_point.name, csr);
282 		return;
283 	}
284 
285 	if (csr & MUSB_TXCSR_P_SENDSTALL) {
286 		musb_dbg(musb, "%s stalling, txcsr %03x",
287 				musb_ep->end_point.name, csr);
288 		return;
289 	}
290 
291 	musb_dbg(musb, "hw_ep%d, maxpacket %d, fifo count %d, txcsr %03x",
292 			epnum, musb_ep->packet_sz, fifo_count,
293 			csr);
294 
295 #ifndef	CONFIG_MUSB_PIO_ONLY
296 	if (is_buffer_mapped(req)) {
297 		struct dma_controller	*c = musb->dma_controller;
298 		size_t request_size;
299 
300 		/* setup DMA, then program endpoint CSR */
301 		request_size = min_t(size_t, request->length - request->actual,
302 					musb_ep->dma->max_len);
303 
304 		use_dma = (request->dma != DMA_ADDR_INVALID && request_size);
305 
306 		/* MUSB_TXCSR_P_ISO is still set correctly */
307 
308 		if (musb_dma_inventra(musb) || musb_dma_ux500(musb)) {
309 			if (request_size < musb_ep->packet_sz)
310 				musb_ep->dma->desired_mode = 0;
311 			else
312 				musb_ep->dma->desired_mode = 1;
313 
314 			use_dma = use_dma && c->channel_program(
315 					musb_ep->dma, musb_ep->packet_sz,
316 					musb_ep->dma->desired_mode,
317 					request->dma + request->actual, request_size);
318 			if (use_dma) {
319 				if (musb_ep->dma->desired_mode == 0) {
320 					/*
321 					 * We must not clear the DMAMODE bit
322 					 * before the DMAENAB bit -- and the
323 					 * latter doesn't always get cleared
324 					 * before we get here...
325 					 */
326 					csr &= ~(MUSB_TXCSR_AUTOSET
327 						| MUSB_TXCSR_DMAENAB);
328 					musb_writew(epio, MUSB_TXCSR, csr
329 						| MUSB_TXCSR_P_WZC_BITS);
330 					csr &= ~MUSB_TXCSR_DMAMODE;
331 					csr |= (MUSB_TXCSR_DMAENAB |
332 							MUSB_TXCSR_MODE);
333 					/* against programming guide */
334 				} else {
335 					csr |= (MUSB_TXCSR_DMAENAB
336 							| MUSB_TXCSR_DMAMODE
337 							| MUSB_TXCSR_MODE);
338 					/*
339 					 * Enable Autoset according to table
340 					 * below
341 					 * bulk_split hb_mult	Autoset_Enable
342 					 *	0	0	Yes(Normal)
343 					 *	0	>0	No(High BW ISO)
344 					 *	1	0	Yes(HS bulk)
345 					 *	1	>0	Yes(FS bulk)
346 					 */
347 					if (!musb_ep->hb_mult ||
348 					    can_bulk_split(musb,
349 							   musb_ep->type))
350 						csr |= MUSB_TXCSR_AUTOSET;
351 				}
352 				csr &= ~MUSB_TXCSR_P_UNDERRUN;
353 
354 				musb_writew(epio, MUSB_TXCSR, csr);
355 			}
356 		}
357 
358 		if (is_cppi_enabled(musb)) {
359 			/* program endpoint CSR first, then setup DMA */
360 			csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
361 			csr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_DMAMODE |
362 				MUSB_TXCSR_MODE;
363 			musb_writew(epio, MUSB_TXCSR, (MUSB_TXCSR_P_WZC_BITS &
364 						~MUSB_TXCSR_P_UNDERRUN) | csr);
365 
366 			/* ensure writebuffer is empty */
367 			csr = musb_readw(epio, MUSB_TXCSR);
368 
369 			/*
370 			 * NOTE host side sets DMAENAB later than this; both are
371 			 * OK since the transfer dma glue (between CPPI and
372 			 * Mentor fifos) just tells CPPI it could start. Data
373 			 * only moves to the USB TX fifo when both fifos are
374 			 * ready.
375 			 */
376 			/*
377 			 * "mode" is irrelevant here; handle terminating ZLPs
378 			 * like PIO does, since the hardware RNDIS mode seems
379 			 * unreliable except for the
380 			 * last-packet-is-already-short case.
381 			 */
382 			use_dma = use_dma && c->channel_program(
383 					musb_ep->dma, musb_ep->packet_sz,
384 					0,
385 					request->dma + request->actual,
386 					request_size);
387 			if (!use_dma) {
388 				c->channel_release(musb_ep->dma);
389 				musb_ep->dma = NULL;
390 				csr &= ~MUSB_TXCSR_DMAENAB;
391 				musb_writew(epio, MUSB_TXCSR, csr);
392 				/* invariant: prequest->buf is non-null */
393 			}
394 		} else if (tusb_dma_omap(musb))
395 			use_dma = use_dma && c->channel_program(
396 					musb_ep->dma, musb_ep->packet_sz,
397 					request->zero,
398 					request->dma + request->actual,
399 					request_size);
400 	}
401 #endif
402 
403 	if (!use_dma) {
404 		/*
405 		 * Unmap the dma buffer back to cpu if dma channel
406 		 * programming fails
407 		 */
408 		unmap_dma_buffer(req, musb);
409 
410 		musb_write_fifo(musb_ep->hw_ep, fifo_count,
411 				(u8 *) (request->buf + request->actual));
412 		request->actual += fifo_count;
413 		csr |= MUSB_TXCSR_TXPKTRDY;
414 		csr &= ~MUSB_TXCSR_P_UNDERRUN;
415 		musb_writew(epio, MUSB_TXCSR, csr);
416 	}
417 
418 	/* host may already have the data when this message shows... */
419 	musb_dbg(musb, "%s TX/IN %s len %d/%d, txcsr %04x, fifo %d/%d",
420 			musb_ep->end_point.name, use_dma ? "dma" : "pio",
421 			request->actual, request->length,
422 			musb_readw(epio, MUSB_TXCSR),
423 			fifo_count,
424 			musb_readw(epio, MUSB_TXMAXP));
425 }
426 
427 /*
428  * FIFO state update (e.g. data ready).
429  * Called from IRQ,  with controller locked.
430  */
musb_g_tx(struct musb * musb,u8 epnum)431 void musb_g_tx(struct musb *musb, u8 epnum)
432 {
433 	u16			csr;
434 	struct musb_request	*req;
435 	struct usb_request	*request;
436 	u8 __iomem		*mbase = musb->mregs;
437 	struct musb_ep		*musb_ep = &musb->endpoints[epnum].ep_in;
438 	void __iomem		*epio = musb->endpoints[epnum].regs;
439 	struct dma_channel	*dma;
440 
441 	musb_ep_select(mbase, epnum);
442 	req = next_request(musb_ep);
443 	request = &req->request;
444 
445 	csr = musb_readw(epio, MUSB_TXCSR);
446 	musb_dbg(musb, "<== %s, txcsr %04x", musb_ep->end_point.name, csr);
447 
448 	dma = is_dma_capable() ? musb_ep->dma : NULL;
449 
450 	/*
451 	 * REVISIT: for high bandwidth, MUSB_TXCSR_P_INCOMPTX
452 	 * probably rates reporting as a host error.
453 	 */
454 	if (csr & MUSB_TXCSR_P_SENTSTALL) {
455 		csr |=	MUSB_TXCSR_P_WZC_BITS;
456 		csr &= ~MUSB_TXCSR_P_SENTSTALL;
457 		musb_writew(epio, MUSB_TXCSR, csr);
458 		return;
459 	}
460 
461 	if (csr & MUSB_TXCSR_P_UNDERRUN) {
462 		/* We NAKed, no big deal... little reason to care. */
463 		csr |=	 MUSB_TXCSR_P_WZC_BITS;
464 		csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
465 		musb_writew(epio, MUSB_TXCSR, csr);
466 		dev_vdbg(musb->controller, "underrun on ep%d, req %p\n",
467 				epnum, request);
468 	}
469 
470 	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
471 		/*
472 		 * SHOULD NOT HAPPEN... has with CPPI though, after
473 		 * changing SENDSTALL (and other cases); harmless?
474 		 */
475 		musb_dbg(musb, "%s dma still busy?", musb_ep->end_point.name);
476 		return;
477 	}
478 
479 	if (request) {
480 
481 		trace_musb_req_tx(req);
482 
483 		if (dma && (csr & MUSB_TXCSR_DMAENAB)) {
484 			csr |= MUSB_TXCSR_P_WZC_BITS;
485 			csr &= ~(MUSB_TXCSR_DMAENAB | MUSB_TXCSR_P_UNDERRUN |
486 				 MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_AUTOSET);
487 			musb_writew(epio, MUSB_TXCSR, csr);
488 			/* Ensure writebuffer is empty. */
489 			csr = musb_readw(epio, MUSB_TXCSR);
490 			request->actual += musb_ep->dma->actual_len;
491 			musb_dbg(musb, "TXCSR%d %04x, DMA off, len %zu, req %p",
492 				epnum, csr, musb_ep->dma->actual_len, request);
493 		}
494 
495 		/*
496 		 * First, maybe a terminating short packet. Some DMA
497 		 * engines might handle this by themselves.
498 		 */
499 		if ((request->zero && request->length)
500 			&& (request->length % musb_ep->packet_sz == 0)
501 			&& (request->actual == request->length)) {
502 
503 			/*
504 			 * On DMA completion, FIFO may not be
505 			 * available yet...
506 			 */
507 			if (csr & MUSB_TXCSR_TXPKTRDY)
508 				return;
509 
510 			musb_writew(epio, MUSB_TXCSR, MUSB_TXCSR_MODE
511 					| MUSB_TXCSR_TXPKTRDY);
512 			request->zero = 0;
513 		}
514 
515 		if (request->actual == request->length) {
516 			musb_g_giveback(musb_ep, request, 0);
517 			/*
518 			 * In the giveback function the MUSB lock is
519 			 * released and acquired after sometime. During
520 			 * this time period the INDEX register could get
521 			 * changed by the gadget_queue function especially
522 			 * on SMP systems. Reselect the INDEX to be sure
523 			 * we are reading/modifying the right registers
524 			 */
525 			musb_ep_select(mbase, epnum);
526 			req = musb_ep->desc ? next_request(musb_ep) : NULL;
527 			if (!req) {
528 				musb_dbg(musb, "%s idle now",
529 					musb_ep->end_point.name);
530 				return;
531 			}
532 		}
533 
534 		txstate(musb, req);
535 	}
536 }
537 
538 /* ------------------------------------------------------------ */
539 
540 /*
541  * Context: controller locked, IRQs blocked, endpoint selected
542  */
rxstate(struct musb * musb,struct musb_request * req)543 static void rxstate(struct musb *musb, struct musb_request *req)
544 {
545 	const u8		epnum = req->epnum;
546 	struct usb_request	*request = &req->request;
547 	struct musb_ep		*musb_ep;
548 	void __iomem		*epio = musb->endpoints[epnum].regs;
549 	unsigned		len = 0;
550 	u16			fifo_count;
551 	u16			csr = musb_readw(epio, MUSB_RXCSR);
552 	struct musb_hw_ep	*hw_ep = &musb->endpoints[epnum];
553 	u8			use_mode_1;
554 
555 	if (hw_ep->is_shared_fifo)
556 		musb_ep = &hw_ep->ep_in;
557 	else
558 		musb_ep = &hw_ep->ep_out;
559 
560 	fifo_count = musb_ep->packet_sz;
561 
562 	/* Check if EP is disabled */
563 	if (!musb_ep->desc) {
564 		musb_dbg(musb, "ep:%s disabled - ignore request",
565 						musb_ep->end_point.name);
566 		return;
567 	}
568 
569 	/* We shouldn't get here while DMA is active, but we do... */
570 	if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) {
571 		musb_dbg(musb, "DMA pending...");
572 		return;
573 	}
574 
575 	if (csr & MUSB_RXCSR_P_SENDSTALL) {
576 		musb_dbg(musb, "%s stalling, RXCSR %04x",
577 		    musb_ep->end_point.name, csr);
578 		return;
579 	}
580 
581 	if (is_cppi_enabled(musb) && is_buffer_mapped(req)) {
582 		struct dma_controller	*c = musb->dma_controller;
583 		struct dma_channel	*channel = musb_ep->dma;
584 
585 		/* NOTE:  CPPI won't actually stop advancing the DMA
586 		 * queue after short packet transfers, so this is almost
587 		 * always going to run as IRQ-per-packet DMA so that
588 		 * faults will be handled correctly.
589 		 */
590 		if (c->channel_program(channel,
591 				musb_ep->packet_sz,
592 				!request->short_not_ok,
593 				request->dma + request->actual,
594 				request->length - request->actual)) {
595 
596 			/* make sure that if an rxpkt arrived after the irq,
597 			 * the cppi engine will be ready to take it as soon
598 			 * as DMA is enabled
599 			 */
600 			csr &= ~(MUSB_RXCSR_AUTOCLEAR
601 					| MUSB_RXCSR_DMAMODE);
602 			csr |= MUSB_RXCSR_DMAENAB | MUSB_RXCSR_P_WZC_BITS;
603 			musb_writew(epio, MUSB_RXCSR, csr);
604 			return;
605 		}
606 	}
607 
608 	if (csr & MUSB_RXCSR_RXPKTRDY) {
609 		fifo_count = musb_readw(epio, MUSB_RXCOUNT);
610 
611 		/*
612 		 * Enable Mode 1 on RX transfers only when short_not_ok flag
613 		 * is set. Currently short_not_ok flag is set only from
614 		 * file_storage and f_mass_storage drivers
615 		 */
616 
617 		if (request->short_not_ok && fifo_count == musb_ep->packet_sz)
618 			use_mode_1 = 1;
619 		else
620 			use_mode_1 = 0;
621 
622 		if (request->actual < request->length) {
623 			if (!is_buffer_mapped(req))
624 				goto buffer_aint_mapped;
625 
626 			if (musb_dma_inventra(musb)) {
627 				struct dma_controller	*c;
628 				struct dma_channel	*channel;
629 				int			use_dma = 0;
630 				unsigned int transfer_size;
631 
632 				c = musb->dma_controller;
633 				channel = musb_ep->dma;
634 
635 	/* We use DMA Req mode 0 in rx_csr, and DMA controller operates in
636 	 * mode 0 only. So we do not get endpoint interrupts due to DMA
637 	 * completion. We only get interrupts from DMA controller.
638 	 *
639 	 * We could operate in DMA mode 1 if we knew the size of the tranfer
640 	 * in advance. For mass storage class, request->length = what the host
641 	 * sends, so that'd work.  But for pretty much everything else,
642 	 * request->length is routinely more than what the host sends. For
643 	 * most these gadgets, end of is signified either by a short packet,
644 	 * or filling the last byte of the buffer.  (Sending extra data in
645 	 * that last pckate should trigger an overflow fault.)  But in mode 1,
646 	 * we don't get DMA completion interrupt for short packets.
647 	 *
648 	 * Theoretically, we could enable DMAReq irq (MUSB_RXCSR_DMAMODE = 1),
649 	 * to get endpoint interrupt on every DMA req, but that didn't seem
650 	 * to work reliably.
651 	 *
652 	 * REVISIT an updated g_file_storage can set req->short_not_ok, which
653 	 * then becomes usable as a runtime "use mode 1" hint...
654 	 */
655 
656 				/* Experimental: Mode1 works with mass storage use cases */
657 				if (use_mode_1) {
658 					csr |= MUSB_RXCSR_AUTOCLEAR;
659 					musb_writew(epio, MUSB_RXCSR, csr);
660 					csr |= MUSB_RXCSR_DMAENAB;
661 					musb_writew(epio, MUSB_RXCSR, csr);
662 
663 					/*
664 					 * this special sequence (enabling and then
665 					 * disabling MUSB_RXCSR_DMAMODE) is required
666 					 * to get DMAReq to activate
667 					 */
668 					musb_writew(epio, MUSB_RXCSR,
669 						csr | MUSB_RXCSR_DMAMODE);
670 					musb_writew(epio, MUSB_RXCSR, csr);
671 
672 					transfer_size = min_t(unsigned int,
673 							request->length -
674 							request->actual,
675 							channel->max_len);
676 					musb_ep->dma->desired_mode = 1;
677 				} else {
678 					if (!musb_ep->hb_mult &&
679 						musb_ep->hw_ep->rx_double_buffered)
680 						csr |= MUSB_RXCSR_AUTOCLEAR;
681 					csr |= MUSB_RXCSR_DMAENAB;
682 					musb_writew(epio, MUSB_RXCSR, csr);
683 
684 					transfer_size = min(request->length - request->actual,
685 							(unsigned)fifo_count);
686 					musb_ep->dma->desired_mode = 0;
687 				}
688 
689 				use_dma = c->channel_program(
690 						channel,
691 						musb_ep->packet_sz,
692 						channel->desired_mode,
693 						request->dma
694 						+ request->actual,
695 						transfer_size);
696 
697 				if (use_dma)
698 					return;
699 			}
700 
701 			if ((musb_dma_ux500(musb)) &&
702 				(request->actual < request->length)) {
703 
704 				struct dma_controller *c;
705 				struct dma_channel *channel;
706 				unsigned int transfer_size = 0;
707 
708 				c = musb->dma_controller;
709 				channel = musb_ep->dma;
710 
711 				/* In case first packet is short */
712 				if (fifo_count < musb_ep->packet_sz)
713 					transfer_size = fifo_count;
714 				else if (request->short_not_ok)
715 					transfer_size =	min_t(unsigned int,
716 							request->length -
717 							request->actual,
718 							channel->max_len);
719 				else
720 					transfer_size = min_t(unsigned int,
721 							request->length -
722 							request->actual,
723 							(unsigned)fifo_count);
724 
725 				csr &= ~MUSB_RXCSR_DMAMODE;
726 				csr |= (MUSB_RXCSR_DMAENAB |
727 					MUSB_RXCSR_AUTOCLEAR);
728 
729 				musb_writew(epio, MUSB_RXCSR, csr);
730 
731 				if (transfer_size <= musb_ep->packet_sz) {
732 					musb_ep->dma->desired_mode = 0;
733 				} else {
734 					musb_ep->dma->desired_mode = 1;
735 					/* Mode must be set after DMAENAB */
736 					csr |= MUSB_RXCSR_DMAMODE;
737 					musb_writew(epio, MUSB_RXCSR, csr);
738 				}
739 
740 				if (c->channel_program(channel,
741 							musb_ep->packet_sz,
742 							channel->desired_mode,
743 							request->dma
744 							+ request->actual,
745 							transfer_size))
746 
747 					return;
748 			}
749 
750 			len = request->length - request->actual;
751 			musb_dbg(musb, "%s OUT/RX pio fifo %d/%d, maxpacket %d",
752 					musb_ep->end_point.name,
753 					fifo_count, len,
754 					musb_ep->packet_sz);
755 
756 			fifo_count = min_t(unsigned, len, fifo_count);
757 
758 			if (tusb_dma_omap(musb)) {
759 				struct dma_controller *c = musb->dma_controller;
760 				struct dma_channel *channel = musb_ep->dma;
761 				u32 dma_addr = request->dma + request->actual;
762 				int ret;
763 
764 				ret = c->channel_program(channel,
765 						musb_ep->packet_sz,
766 						channel->desired_mode,
767 						dma_addr,
768 						fifo_count);
769 				if (ret)
770 					return;
771 			}
772 
773 			/*
774 			 * Unmap the dma buffer back to cpu if dma channel
775 			 * programming fails. This buffer is mapped if the
776 			 * channel allocation is successful
777 			 */
778 			unmap_dma_buffer(req, musb);
779 
780 			/*
781 			 * Clear DMAENAB and AUTOCLEAR for the
782 			 * PIO mode transfer
783 			 */
784 			csr &= ~(MUSB_RXCSR_DMAENAB | MUSB_RXCSR_AUTOCLEAR);
785 			musb_writew(epio, MUSB_RXCSR, csr);
786 
787 buffer_aint_mapped:
788 			musb_read_fifo(musb_ep->hw_ep, fifo_count, (u8 *)
789 					(request->buf + request->actual));
790 			request->actual += fifo_count;
791 
792 			/* REVISIT if we left anything in the fifo, flush
793 			 * it and report -EOVERFLOW
794 			 */
795 
796 			/* ack the read! */
797 			csr |= MUSB_RXCSR_P_WZC_BITS;
798 			csr &= ~MUSB_RXCSR_RXPKTRDY;
799 			musb_writew(epio, MUSB_RXCSR, csr);
800 		}
801 	}
802 
803 	/* reach the end or short packet detected */
804 	if (request->actual == request->length ||
805 	    fifo_count < musb_ep->packet_sz)
806 		musb_g_giveback(musb_ep, request, 0);
807 }
808 
809 /*
810  * Data ready for a request; called from IRQ
811  */
musb_g_rx(struct musb * musb,u8 epnum)812 void musb_g_rx(struct musb *musb, u8 epnum)
813 {
814 	u16			csr;
815 	struct musb_request	*req;
816 	struct usb_request	*request;
817 	void __iomem		*mbase = musb->mregs;
818 	struct musb_ep		*musb_ep;
819 	void __iomem		*epio = musb->endpoints[epnum].regs;
820 	struct dma_channel	*dma;
821 	struct musb_hw_ep	*hw_ep = &musb->endpoints[epnum];
822 
823 	if (hw_ep->is_shared_fifo)
824 		musb_ep = &hw_ep->ep_in;
825 	else
826 		musb_ep = &hw_ep->ep_out;
827 
828 	musb_ep_select(mbase, epnum);
829 
830 	req = next_request(musb_ep);
831 	if (!req)
832 		return;
833 
834 	trace_musb_req_rx(req);
835 	request = &req->request;
836 
837 	csr = musb_readw(epio, MUSB_RXCSR);
838 	dma = is_dma_capable() ? musb_ep->dma : NULL;
839 
840 	musb_dbg(musb, "<== %s, rxcsr %04x%s %p", musb_ep->end_point.name,
841 			csr, dma ? " (dma)" : "", request);
842 
843 	if (csr & MUSB_RXCSR_P_SENTSTALL) {
844 		csr |= MUSB_RXCSR_P_WZC_BITS;
845 		csr &= ~MUSB_RXCSR_P_SENTSTALL;
846 		musb_writew(epio, MUSB_RXCSR, csr);
847 		return;
848 	}
849 
850 	if (csr & MUSB_RXCSR_P_OVERRUN) {
851 		/* csr |= MUSB_RXCSR_P_WZC_BITS; */
852 		csr &= ~MUSB_RXCSR_P_OVERRUN;
853 		musb_writew(epio, MUSB_RXCSR, csr);
854 
855 		musb_dbg(musb, "%s iso overrun on %p", musb_ep->name, request);
856 		if (request->status == -EINPROGRESS)
857 			request->status = -EOVERFLOW;
858 	}
859 	if (csr & MUSB_RXCSR_INCOMPRX) {
860 		/* REVISIT not necessarily an error */
861 		musb_dbg(musb, "%s, incomprx", musb_ep->end_point.name);
862 	}
863 
864 	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
865 		/* "should not happen"; likely RXPKTRDY pending for DMA */
866 		musb_dbg(musb, "%s busy, csr %04x",
867 			musb_ep->end_point.name, csr);
868 		return;
869 	}
870 
871 	if (dma && (csr & MUSB_RXCSR_DMAENAB)) {
872 		csr &= ~(MUSB_RXCSR_AUTOCLEAR
873 				| MUSB_RXCSR_DMAENAB
874 				| MUSB_RXCSR_DMAMODE);
875 		musb_writew(epio, MUSB_RXCSR,
876 			MUSB_RXCSR_P_WZC_BITS | csr);
877 
878 		request->actual += musb_ep->dma->actual_len;
879 
880 #if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_TUSB_OMAP_DMA) || \
881 	defined(CONFIG_USB_UX500_DMA)
882 		/* Autoclear doesn't clear RxPktRdy for short packets */
883 		if ((dma->desired_mode == 0 && !hw_ep->rx_double_buffered)
884 				|| (dma->actual_len
885 					& (musb_ep->packet_sz - 1))) {
886 			/* ack the read! */
887 			csr &= ~MUSB_RXCSR_RXPKTRDY;
888 			musb_writew(epio, MUSB_RXCSR, csr);
889 		}
890 
891 		/* incomplete, and not short? wait for next IN packet */
892 		if ((request->actual < request->length)
893 				&& (musb_ep->dma->actual_len
894 					== musb_ep->packet_sz)) {
895 			/* In double buffer case, continue to unload fifo if
896  			 * there is Rx packet in FIFO.
897  			 **/
898 			csr = musb_readw(epio, MUSB_RXCSR);
899 			if ((csr & MUSB_RXCSR_RXPKTRDY) &&
900 				hw_ep->rx_double_buffered)
901 				goto exit;
902 			return;
903 		}
904 #endif
905 		musb_g_giveback(musb_ep, request, 0);
906 		/*
907 		 * In the giveback function the MUSB lock is
908 		 * released and acquired after sometime. During
909 		 * this time period the INDEX register could get
910 		 * changed by the gadget_queue function especially
911 		 * on SMP systems. Reselect the INDEX to be sure
912 		 * we are reading/modifying the right registers
913 		 */
914 		musb_ep_select(mbase, epnum);
915 
916 		req = next_request(musb_ep);
917 		if (!req)
918 			return;
919 	}
920 #if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_TUSB_OMAP_DMA) || \
921 	defined(CONFIG_USB_UX500_DMA)
922 exit:
923 #endif
924 	/* Analyze request */
925 	rxstate(musb, req);
926 }
927 
928 /* ------------------------------------------------------------ */
929 
musb_gadget_enable(struct usb_ep * ep,const struct usb_endpoint_descriptor * desc)930 static int musb_gadget_enable(struct usb_ep *ep,
931 			const struct usb_endpoint_descriptor *desc)
932 {
933 	unsigned long		flags;
934 	struct musb_ep		*musb_ep;
935 	struct musb_hw_ep	*hw_ep;
936 	void __iomem		*regs;
937 	struct musb		*musb;
938 	void __iomem	*mbase;
939 	u8		epnum;
940 	u16		csr;
941 	unsigned	tmp;
942 	int		status = -EINVAL;
943 
944 	if (!ep || !desc)
945 		return -EINVAL;
946 
947 	musb_ep = to_musb_ep(ep);
948 	hw_ep = musb_ep->hw_ep;
949 	regs = hw_ep->regs;
950 	musb = musb_ep->musb;
951 	mbase = musb->mregs;
952 	epnum = musb_ep->current_epnum;
953 
954 	spin_lock_irqsave(&musb->lock, flags);
955 
956 	if (musb_ep->desc) {
957 		status = -EBUSY;
958 		goto fail;
959 	}
960 	musb_ep->type = usb_endpoint_type(desc);
961 
962 	/* check direction and (later) maxpacket size against endpoint */
963 	if (usb_endpoint_num(desc) != epnum)
964 		goto fail;
965 
966 	/* REVISIT this rules out high bandwidth periodic transfers */
967 	tmp = usb_endpoint_maxp_mult(desc) - 1;
968 	if (tmp) {
969 		int ok;
970 
971 		if (usb_endpoint_dir_in(desc))
972 			ok = musb->hb_iso_tx;
973 		else
974 			ok = musb->hb_iso_rx;
975 
976 		if (!ok) {
977 			musb_dbg(musb, "no support for high bandwidth ISO");
978 			goto fail;
979 		}
980 		musb_ep->hb_mult = tmp;
981 	} else {
982 		musb_ep->hb_mult = 0;
983 	}
984 
985 	musb_ep->packet_sz = usb_endpoint_maxp(desc);
986 	tmp = musb_ep->packet_sz * (musb_ep->hb_mult + 1);
987 
988 	/* enable the interrupts for the endpoint, set the endpoint
989 	 * packet size (or fail), set the mode, clear the fifo
990 	 */
991 	musb_ep_select(mbase, epnum);
992 	if (usb_endpoint_dir_in(desc)) {
993 
994 		if (hw_ep->is_shared_fifo)
995 			musb_ep->is_in = 1;
996 		if (!musb_ep->is_in)
997 			goto fail;
998 
999 		if (tmp > hw_ep->max_packet_sz_tx) {
1000 			musb_dbg(musb, "packet size beyond hardware FIFO size");
1001 			goto fail;
1002 		}
1003 
1004 		musb->intrtxe |= (1 << epnum);
1005 		musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe);
1006 
1007 		/* REVISIT if can_bulk_split(), use by updating "tmp";
1008 		 * likewise high bandwidth periodic tx
1009 		 */
1010 		/* Set TXMAXP with the FIFO size of the endpoint
1011 		 * to disable double buffering mode.
1012 		 */
1013 		if (musb->double_buffer_not_ok) {
1014 			musb_writew(regs, MUSB_TXMAXP, hw_ep->max_packet_sz_tx);
1015 		} else {
1016 			if (can_bulk_split(musb, musb_ep->type))
1017 				musb_ep->hb_mult = (hw_ep->max_packet_sz_tx /
1018 							musb_ep->packet_sz) - 1;
1019 			musb_writew(regs, MUSB_TXMAXP, musb_ep->packet_sz
1020 					| (musb_ep->hb_mult << 11));
1021 		}
1022 
1023 		csr = MUSB_TXCSR_MODE | MUSB_TXCSR_CLRDATATOG;
1024 		if (musb_readw(regs, MUSB_TXCSR)
1025 				& MUSB_TXCSR_FIFONOTEMPTY)
1026 			csr |= MUSB_TXCSR_FLUSHFIFO;
1027 		if (musb_ep->type == USB_ENDPOINT_XFER_ISOC)
1028 			csr |= MUSB_TXCSR_P_ISO;
1029 
1030 		/* set twice in case of double buffering */
1031 		musb_writew(regs, MUSB_TXCSR, csr);
1032 		/* REVISIT may be inappropriate w/o FIFONOTEMPTY ... */
1033 		musb_writew(regs, MUSB_TXCSR, csr);
1034 
1035 	} else {
1036 
1037 		if (hw_ep->is_shared_fifo)
1038 			musb_ep->is_in = 0;
1039 		if (musb_ep->is_in)
1040 			goto fail;
1041 
1042 		if (tmp > hw_ep->max_packet_sz_rx) {
1043 			musb_dbg(musb, "packet size beyond hardware FIFO size");
1044 			goto fail;
1045 		}
1046 
1047 		musb->intrrxe |= (1 << epnum);
1048 		musb_writew(mbase, MUSB_INTRRXE, musb->intrrxe);
1049 
1050 		/* REVISIT if can_bulk_combine() use by updating "tmp"
1051 		 * likewise high bandwidth periodic rx
1052 		 */
1053 		/* Set RXMAXP with the FIFO size of the endpoint
1054 		 * to disable double buffering mode.
1055 		 */
1056 		if (musb->double_buffer_not_ok)
1057 			musb_writew(regs, MUSB_RXMAXP, hw_ep->max_packet_sz_tx);
1058 		else
1059 			musb_writew(regs, MUSB_RXMAXP, musb_ep->packet_sz
1060 					| (musb_ep->hb_mult << 11));
1061 
1062 		/* force shared fifo to OUT-only mode */
1063 		if (hw_ep->is_shared_fifo) {
1064 			csr = musb_readw(regs, MUSB_TXCSR);
1065 			csr &= ~(MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY);
1066 			musb_writew(regs, MUSB_TXCSR, csr);
1067 		}
1068 
1069 		csr = MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_CLRDATATOG;
1070 		if (musb_ep->type == USB_ENDPOINT_XFER_ISOC)
1071 			csr |= MUSB_RXCSR_P_ISO;
1072 		else if (musb_ep->type == USB_ENDPOINT_XFER_INT)
1073 			csr |= MUSB_RXCSR_DISNYET;
1074 
1075 		/* set twice in case of double buffering */
1076 		musb_writew(regs, MUSB_RXCSR, csr);
1077 		musb_writew(regs, MUSB_RXCSR, csr);
1078 	}
1079 
1080 	/* NOTE:  all the I/O code _should_ work fine without DMA, in case
1081 	 * for some reason you run out of channels here.
1082 	 */
1083 	if (is_dma_capable() && musb->dma_controller) {
1084 		struct dma_controller	*c = musb->dma_controller;
1085 
1086 		musb_ep->dma = c->channel_alloc(c, hw_ep,
1087 				(desc->bEndpointAddress & USB_DIR_IN));
1088 	} else
1089 		musb_ep->dma = NULL;
1090 
1091 	musb_ep->desc = desc;
1092 	musb_ep->busy = 0;
1093 	musb_ep->wedged = 0;
1094 	status = 0;
1095 
1096 	pr_debug("%s periph: enabled %s for %s %s, %smaxpacket %d\n",
1097 			musb_driver_name, musb_ep->end_point.name,
1098 			musb_ep_xfertype_string(musb_ep->type),
1099 			musb_ep->is_in ? "IN" : "OUT",
1100 			musb_ep->dma ? "dma, " : "",
1101 			musb_ep->packet_sz);
1102 
1103 	schedule_delayed_work(&musb->irq_work, 0);
1104 
1105 fail:
1106 	spin_unlock_irqrestore(&musb->lock, flags);
1107 	return status;
1108 }
1109 
1110 /*
1111  * Disable an endpoint flushing all requests queued.
1112  */
musb_gadget_disable(struct usb_ep * ep)1113 static int musb_gadget_disable(struct usb_ep *ep)
1114 {
1115 	unsigned long	flags;
1116 	struct musb	*musb;
1117 	u8		epnum;
1118 	struct musb_ep	*musb_ep;
1119 	void __iomem	*epio;
1120 	int		status = 0;
1121 
1122 	musb_ep = to_musb_ep(ep);
1123 	musb = musb_ep->musb;
1124 	epnum = musb_ep->current_epnum;
1125 	epio = musb->endpoints[epnum].regs;
1126 
1127 	spin_lock_irqsave(&musb->lock, flags);
1128 	musb_ep_select(musb->mregs, epnum);
1129 
1130 	/* zero the endpoint sizes */
1131 	if (musb_ep->is_in) {
1132 		musb->intrtxe &= ~(1 << epnum);
1133 		musb_writew(musb->mregs, MUSB_INTRTXE, musb->intrtxe);
1134 		musb_writew(epio, MUSB_TXMAXP, 0);
1135 	} else {
1136 		musb->intrrxe &= ~(1 << epnum);
1137 		musb_writew(musb->mregs, MUSB_INTRRXE, musb->intrrxe);
1138 		musb_writew(epio, MUSB_RXMAXP, 0);
1139 	}
1140 
1141 	/* abort all pending DMA and requests */
1142 	nuke(musb_ep, -ESHUTDOWN);
1143 
1144 	musb_ep->desc = NULL;
1145 	musb_ep->end_point.desc = NULL;
1146 
1147 	schedule_delayed_work(&musb->irq_work, 0);
1148 
1149 	spin_unlock_irqrestore(&(musb->lock), flags);
1150 
1151 	musb_dbg(musb, "%s", musb_ep->end_point.name);
1152 
1153 	return status;
1154 }
1155 
1156 /*
1157  * Allocate a request for an endpoint.
1158  * Reused by ep0 code.
1159  */
musb_alloc_request(struct usb_ep * ep,gfp_t gfp_flags)1160 struct usb_request *musb_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1161 {
1162 	struct musb_ep		*musb_ep = to_musb_ep(ep);
1163 	struct musb_request	*request = NULL;
1164 
1165 	request = kzalloc(sizeof *request, gfp_flags);
1166 	if (!request)
1167 		return NULL;
1168 
1169 	request->request.dma = DMA_ADDR_INVALID;
1170 	request->epnum = musb_ep->current_epnum;
1171 	request->ep = musb_ep;
1172 
1173 	trace_musb_req_alloc(request);
1174 	return &request->request;
1175 }
1176 
1177 /*
1178  * Free a request
1179  * Reused by ep0 code.
1180  */
musb_free_request(struct usb_ep * ep,struct usb_request * req)1181 void musb_free_request(struct usb_ep *ep, struct usb_request *req)
1182 {
1183 	struct musb_request *request = to_musb_request(req);
1184 
1185 	trace_musb_req_free(request);
1186 	kfree(request);
1187 }
1188 
1189 static LIST_HEAD(buffers);
1190 
1191 struct free_record {
1192 	struct list_head	list;
1193 	struct device		*dev;
1194 	unsigned		bytes;
1195 	dma_addr_t		dma;
1196 };
1197 
1198 /*
1199  * Context: controller locked, IRQs blocked.
1200  */
musb_ep_restart(struct musb * musb,struct musb_request * req)1201 void musb_ep_restart(struct musb *musb, struct musb_request *req)
1202 {
1203 	trace_musb_req_start(req);
1204 	musb_ep_select(musb->mregs, req->epnum);
1205 	if (req->tx)
1206 		txstate(musb, req);
1207 	else
1208 		rxstate(musb, req);
1209 }
1210 
musb_ep_restart_resume_work(struct musb * musb,void * data)1211 static int musb_ep_restart_resume_work(struct musb *musb, void *data)
1212 {
1213 	struct musb_request *req = data;
1214 
1215 	musb_ep_restart(musb, req);
1216 
1217 	return 0;
1218 }
1219 
musb_gadget_queue(struct usb_ep * ep,struct usb_request * req,gfp_t gfp_flags)1220 static int musb_gadget_queue(struct usb_ep *ep, struct usb_request *req,
1221 			gfp_t gfp_flags)
1222 {
1223 	struct musb_ep		*musb_ep;
1224 	struct musb_request	*request;
1225 	struct musb		*musb;
1226 	int			status;
1227 	unsigned long		lockflags;
1228 
1229 	if (!ep || !req)
1230 		return -EINVAL;
1231 	if (!req->buf)
1232 		return -ENODATA;
1233 
1234 	musb_ep = to_musb_ep(ep);
1235 	musb = musb_ep->musb;
1236 
1237 	request = to_musb_request(req);
1238 	request->musb = musb;
1239 
1240 	if (request->ep != musb_ep)
1241 		return -EINVAL;
1242 
1243 	status = pm_runtime_get(musb->controller);
1244 	if ((status != -EINPROGRESS) && status < 0) {
1245 		dev_err(musb->controller,
1246 			"pm runtime get failed in %s\n",
1247 			__func__);
1248 		pm_runtime_put_noidle(musb->controller);
1249 
1250 		return status;
1251 	}
1252 	status = 0;
1253 
1254 	trace_musb_req_enq(request);
1255 
1256 	/* request is mine now... */
1257 	request->request.actual = 0;
1258 	request->request.status = -EINPROGRESS;
1259 	request->epnum = musb_ep->current_epnum;
1260 	request->tx = musb_ep->is_in;
1261 
1262 	map_dma_buffer(request, musb, musb_ep);
1263 
1264 	spin_lock_irqsave(&musb->lock, lockflags);
1265 
1266 	/* don't queue if the ep is down */
1267 	if (!musb_ep->desc) {
1268 		musb_dbg(musb, "req %p queued to %s while ep %s",
1269 				req, ep->name, "disabled");
1270 		status = -ESHUTDOWN;
1271 		unmap_dma_buffer(request, musb);
1272 		goto unlock;
1273 	}
1274 
1275 	/* add request to the list */
1276 	list_add_tail(&request->list, &musb_ep->req_list);
1277 
1278 	/* it this is the head of the queue, start i/o ... */
1279 	if (!musb_ep->busy && &request->list == musb_ep->req_list.next) {
1280 		status = musb_queue_resume_work(musb,
1281 						musb_ep_restart_resume_work,
1282 						request);
1283 		if (status < 0)
1284 			dev_err(musb->controller, "%s resume work: %i\n",
1285 				__func__, status);
1286 	}
1287 
1288 unlock:
1289 	spin_unlock_irqrestore(&musb->lock, lockflags);
1290 	pm_runtime_mark_last_busy(musb->controller);
1291 	pm_runtime_put_autosuspend(musb->controller);
1292 
1293 	return status;
1294 }
1295 
musb_gadget_dequeue(struct usb_ep * ep,struct usb_request * request)1296 static 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 || req->ep != musb_ep)
1306 		return -EINVAL;
1307 
1308 	trace_musb_req_deq(req);
1309 
1310 	spin_lock_irqsave(&musb->lock, flags);
1311 
1312 	list_for_each_entry(r, &musb_ep->req_list, list) {
1313 		if (r == req)
1314 			break;
1315 	}
1316 	if (r != req) {
1317 		dev_err(musb->controller, "request %p not queued to %s\n",
1318 				request, ep->name);
1319 		status = -EINVAL;
1320 		goto done;
1321 	}
1322 
1323 	/* if the hardware doesn't have the request, easy ... */
1324 	if (musb_ep->req_list.next != &req->list || musb_ep->busy)
1325 		musb_g_giveback(musb_ep, request, -ECONNRESET);
1326 
1327 	/* ... else abort the dma transfer ... */
1328 	else if (is_dma_capable() && musb_ep->dma) {
1329 		struct dma_controller	*c = musb->dma_controller;
1330 
1331 		musb_ep_select(musb->mregs, musb_ep->current_epnum);
1332 		if (c->channel_abort)
1333 			status = c->channel_abort(musb_ep->dma);
1334 		else
1335 			status = -EBUSY;
1336 		if (status == 0)
1337 			musb_g_giveback(musb_ep, request, -ECONNRESET);
1338 	} else {
1339 		/* NOTE: by sticking to easily tested hardware/driver states,
1340 		 * we leave counting of in-flight packets imprecise.
1341 		 */
1342 		musb_g_giveback(musb_ep, request, -ECONNRESET);
1343 	}
1344 
1345 done:
1346 	spin_unlock_irqrestore(&musb->lock, flags);
1347 	return status;
1348 }
1349 
1350 /*
1351  * Set or clear the halt bit of an endpoint. A halted enpoint won't tx/rx any
1352  * data but will queue requests.
1353  *
1354  * exported to ep0 code
1355  */
musb_gadget_set_halt(struct usb_ep * ep,int value)1356 static int musb_gadget_set_halt(struct usb_ep *ep, int value)
1357 {
1358 	struct musb_ep		*musb_ep = to_musb_ep(ep);
1359 	u8			epnum = musb_ep->current_epnum;
1360 	struct musb		*musb = musb_ep->musb;
1361 	void __iomem		*epio = musb->endpoints[epnum].regs;
1362 	void __iomem		*mbase;
1363 	unsigned long		flags;
1364 	u16			csr;
1365 	struct musb_request	*request;
1366 	int			status = 0;
1367 
1368 	if (!ep)
1369 		return -EINVAL;
1370 	mbase = musb->mregs;
1371 
1372 	spin_lock_irqsave(&musb->lock, flags);
1373 
1374 	if ((USB_ENDPOINT_XFER_ISOC == musb_ep->type)) {
1375 		status = -EINVAL;
1376 		goto done;
1377 	}
1378 
1379 	musb_ep_select(mbase, epnum);
1380 
1381 	request = next_request(musb_ep);
1382 	if (value) {
1383 		if (request) {
1384 			musb_dbg(musb, "request in progress, cannot halt %s",
1385 			    ep->name);
1386 			status = -EAGAIN;
1387 			goto done;
1388 		}
1389 		/* Cannot portably stall with non-empty FIFO */
1390 		if (musb_ep->is_in) {
1391 			csr = musb_readw(epio, MUSB_TXCSR);
1392 			if (csr & MUSB_TXCSR_FIFONOTEMPTY) {
1393 				musb_dbg(musb, "FIFO busy, cannot halt %s",
1394 						ep->name);
1395 				status = -EAGAIN;
1396 				goto done;
1397 			}
1398 		}
1399 	} else
1400 		musb_ep->wedged = 0;
1401 
1402 	/* set/clear the stall and toggle bits */
1403 	musb_dbg(musb, "%s: %s stall", ep->name, value ? "set" : "clear");
1404 	if (musb_ep->is_in) {
1405 		csr = musb_readw(epio, MUSB_TXCSR);
1406 		csr |= MUSB_TXCSR_P_WZC_BITS
1407 			| MUSB_TXCSR_CLRDATATOG;
1408 		if (value)
1409 			csr |= MUSB_TXCSR_P_SENDSTALL;
1410 		else
1411 			csr &= ~(MUSB_TXCSR_P_SENDSTALL
1412 				| MUSB_TXCSR_P_SENTSTALL);
1413 		csr &= ~MUSB_TXCSR_TXPKTRDY;
1414 		musb_writew(epio, MUSB_TXCSR, csr);
1415 	} else {
1416 		csr = musb_readw(epio, MUSB_RXCSR);
1417 		csr |= MUSB_RXCSR_P_WZC_BITS
1418 			| MUSB_RXCSR_FLUSHFIFO
1419 			| MUSB_RXCSR_CLRDATATOG;
1420 		if (value)
1421 			csr |= MUSB_RXCSR_P_SENDSTALL;
1422 		else
1423 			csr &= ~(MUSB_RXCSR_P_SENDSTALL
1424 				| MUSB_RXCSR_P_SENTSTALL);
1425 		musb_writew(epio, MUSB_RXCSR, csr);
1426 	}
1427 
1428 	/* maybe start the first request in the queue */
1429 	if (!musb_ep->busy && !value && request) {
1430 		musb_dbg(musb, "restarting the request");
1431 		musb_ep_restart(musb, request);
1432 	}
1433 
1434 done:
1435 	spin_unlock_irqrestore(&musb->lock, flags);
1436 	return status;
1437 }
1438 
1439 /*
1440  * Sets the halt feature with the clear requests ignored
1441  */
musb_gadget_set_wedge(struct usb_ep * ep)1442 static int musb_gadget_set_wedge(struct usb_ep *ep)
1443 {
1444 	struct musb_ep		*musb_ep = to_musb_ep(ep);
1445 
1446 	if (!ep)
1447 		return -EINVAL;
1448 
1449 	musb_ep->wedged = 1;
1450 
1451 	return usb_ep_set_halt(ep);
1452 }
1453 
musb_gadget_fifo_status(struct usb_ep * ep)1454 static int musb_gadget_fifo_status(struct usb_ep *ep)
1455 {
1456 	struct musb_ep		*musb_ep = to_musb_ep(ep);
1457 	void __iomem		*epio = musb_ep->hw_ep->regs;
1458 	int			retval = -EINVAL;
1459 
1460 	if (musb_ep->desc && !musb_ep->is_in) {
1461 		struct musb		*musb = musb_ep->musb;
1462 		int			epnum = musb_ep->current_epnum;
1463 		void __iomem		*mbase = musb->mregs;
1464 		unsigned long		flags;
1465 
1466 		spin_lock_irqsave(&musb->lock, flags);
1467 
1468 		musb_ep_select(mbase, epnum);
1469 		/* FIXME return zero unless RXPKTRDY is set */
1470 		retval = musb_readw(epio, MUSB_RXCOUNT);
1471 
1472 		spin_unlock_irqrestore(&musb->lock, flags);
1473 	}
1474 	return retval;
1475 }
1476 
musb_gadget_fifo_flush(struct usb_ep * ep)1477 static void musb_gadget_fifo_flush(struct usb_ep *ep)
1478 {
1479 	struct musb_ep	*musb_ep = to_musb_ep(ep);
1480 	struct musb	*musb = musb_ep->musb;
1481 	u8		epnum = musb_ep->current_epnum;
1482 	void __iomem	*epio = musb->endpoints[epnum].regs;
1483 	void __iomem	*mbase;
1484 	unsigned long	flags;
1485 	u16		csr;
1486 
1487 	mbase = musb->mregs;
1488 
1489 	spin_lock_irqsave(&musb->lock, flags);
1490 	musb_ep_select(mbase, (u8) epnum);
1491 
1492 	/* disable interrupts */
1493 	musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe & ~(1 << epnum));
1494 
1495 	if (musb_ep->is_in) {
1496 		csr = musb_readw(epio, MUSB_TXCSR);
1497 		if (csr & MUSB_TXCSR_FIFONOTEMPTY) {
1498 			csr |= MUSB_TXCSR_FLUSHFIFO | MUSB_TXCSR_P_WZC_BITS;
1499 			/*
1500 			 * Setting both TXPKTRDY and FLUSHFIFO makes controller
1501 			 * to interrupt current FIFO loading, but not flushing
1502 			 * the already loaded ones.
1503 			 */
1504 			csr &= ~MUSB_TXCSR_TXPKTRDY;
1505 			musb_writew(epio, MUSB_TXCSR, csr);
1506 			/* REVISIT may be inappropriate w/o FIFONOTEMPTY ... */
1507 			musb_writew(epio, MUSB_TXCSR, csr);
1508 		}
1509 	} else {
1510 		csr = musb_readw(epio, MUSB_RXCSR);
1511 		csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_P_WZC_BITS;
1512 		musb_writew(epio, MUSB_RXCSR, csr);
1513 		musb_writew(epio, MUSB_RXCSR, csr);
1514 	}
1515 
1516 	/* re-enable interrupt */
1517 	musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe);
1518 	spin_unlock_irqrestore(&musb->lock, flags);
1519 }
1520 
1521 static const struct usb_ep_ops musb_ep_ops = {
1522 	.enable		= musb_gadget_enable,
1523 	.disable	= musb_gadget_disable,
1524 	.alloc_request	= musb_alloc_request,
1525 	.free_request	= musb_free_request,
1526 	.queue		= musb_gadget_queue,
1527 	.dequeue	= musb_gadget_dequeue,
1528 	.set_halt	= musb_gadget_set_halt,
1529 	.set_wedge	= musb_gadget_set_wedge,
1530 	.fifo_status	= musb_gadget_fifo_status,
1531 	.fifo_flush	= musb_gadget_fifo_flush
1532 };
1533 
1534 /* ----------------------------------------------------------------------- */
1535 
musb_gadget_get_frame(struct usb_gadget * gadget)1536 static int musb_gadget_get_frame(struct usb_gadget *gadget)
1537 {
1538 	struct musb	*musb = gadget_to_musb(gadget);
1539 
1540 	return (int)musb_readw(musb->mregs, MUSB_FRAME);
1541 }
1542 
musb_gadget_wakeup(struct usb_gadget * gadget)1543 static int musb_gadget_wakeup(struct usb_gadget *gadget)
1544 {
1545 	struct musb	*musb = gadget_to_musb(gadget);
1546 	void __iomem	*mregs = musb->mregs;
1547 	unsigned long	flags;
1548 	int		status = -EINVAL;
1549 	u8		power, devctl;
1550 	int		retries;
1551 
1552 	spin_lock_irqsave(&musb->lock, flags);
1553 
1554 	switch (musb->xceiv->otg->state) {
1555 	case OTG_STATE_B_PERIPHERAL:
1556 		/* NOTE:  OTG state machine doesn't include B_SUSPENDED;
1557 		 * that's part of the standard usb 1.1 state machine, and
1558 		 * doesn't affect OTG transitions.
1559 		 */
1560 		if (musb->may_wakeup && musb->is_suspended)
1561 			break;
1562 		goto done;
1563 	case OTG_STATE_B_IDLE:
1564 		/* Start SRP ... OTG not required. */
1565 		devctl = musb_readb(mregs, MUSB_DEVCTL);
1566 		musb_dbg(musb, "Sending SRP: devctl: %02x", devctl);
1567 		devctl |= MUSB_DEVCTL_SESSION;
1568 		musb_writeb(mregs, MUSB_DEVCTL, devctl);
1569 		devctl = musb_readb(mregs, MUSB_DEVCTL);
1570 		retries = 100;
1571 		while (!(devctl & MUSB_DEVCTL_SESSION)) {
1572 			devctl = musb_readb(mregs, MUSB_DEVCTL);
1573 			if (retries-- < 1)
1574 				break;
1575 		}
1576 		retries = 10000;
1577 		while (devctl & MUSB_DEVCTL_SESSION) {
1578 			devctl = musb_readb(mregs, MUSB_DEVCTL);
1579 			if (retries-- < 1)
1580 				break;
1581 		}
1582 
1583 		spin_unlock_irqrestore(&musb->lock, flags);
1584 		otg_start_srp(musb->xceiv->otg);
1585 		spin_lock_irqsave(&musb->lock, flags);
1586 
1587 		/* Block idling for at least 1s */
1588 		musb_platform_try_idle(musb,
1589 			jiffies + msecs_to_jiffies(1 * HZ));
1590 
1591 		status = 0;
1592 		goto done;
1593 	default:
1594 		musb_dbg(musb, "Unhandled wake: %s",
1595 			usb_otg_state_string(musb->xceiv->otg->state));
1596 		goto done;
1597 	}
1598 
1599 	status = 0;
1600 
1601 	power = musb_readb(mregs, MUSB_POWER);
1602 	power |= MUSB_POWER_RESUME;
1603 	musb_writeb(mregs, MUSB_POWER, power);
1604 	musb_dbg(musb, "issue wakeup");
1605 
1606 	/* FIXME do this next chunk in a timer callback, no udelay */
1607 	mdelay(2);
1608 
1609 	power = musb_readb(mregs, MUSB_POWER);
1610 	power &= ~MUSB_POWER_RESUME;
1611 	musb_writeb(mregs, MUSB_POWER, power);
1612 done:
1613 	spin_unlock_irqrestore(&musb->lock, flags);
1614 	return status;
1615 }
1616 
1617 static int
musb_gadget_set_self_powered(struct usb_gadget * gadget,int is_selfpowered)1618 musb_gadget_set_self_powered(struct usb_gadget *gadget, int is_selfpowered)
1619 {
1620 	gadget->is_selfpowered = !!is_selfpowered;
1621 	return 0;
1622 }
1623 
musb_pullup(struct musb * musb,int is_on)1624 static void musb_pullup(struct musb *musb, int is_on)
1625 {
1626 	u8 power;
1627 
1628 	power = musb_readb(musb->mregs, MUSB_POWER);
1629 	if (is_on)
1630 		power |= MUSB_POWER_SOFTCONN;
1631 	else
1632 		power &= ~MUSB_POWER_SOFTCONN;
1633 
1634 	/* FIXME if on, HdrcStart; if off, HdrcStop */
1635 
1636 	musb_dbg(musb, "gadget D+ pullup %s",
1637 		is_on ? "on" : "off");
1638 	musb_writeb(musb->mregs, MUSB_POWER, power);
1639 }
1640 
1641 #if 0
1642 static int musb_gadget_vbus_session(struct usb_gadget *gadget, int is_active)
1643 {
1644 	musb_dbg(musb, "<= %s =>\n", __func__);
1645 
1646 	/*
1647 	 * FIXME iff driver's softconnect flag is set (as it is during probe,
1648 	 * though that can clear it), just musb_pullup().
1649 	 */
1650 
1651 	return -EINVAL;
1652 }
1653 #endif
1654 
musb_gadget_vbus_draw(struct usb_gadget * gadget,unsigned mA)1655 static int musb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
1656 {
1657 	struct musb	*musb = gadget_to_musb(gadget);
1658 
1659 	if (!musb->xceiv->set_power)
1660 		return -EOPNOTSUPP;
1661 	return usb_phy_set_power(musb->xceiv, mA);
1662 }
1663 
musb_gadget_work(struct work_struct * work)1664 static void musb_gadget_work(struct work_struct *work)
1665 {
1666 	struct musb *musb;
1667 	unsigned long flags;
1668 
1669 	musb = container_of(work, struct musb, gadget_work.work);
1670 	pm_runtime_get_sync(musb->controller);
1671 	spin_lock_irqsave(&musb->lock, flags);
1672 	musb_pullup(musb, musb->softconnect);
1673 	spin_unlock_irqrestore(&musb->lock, flags);
1674 	pm_runtime_mark_last_busy(musb->controller);
1675 	pm_runtime_put_autosuspend(musb->controller);
1676 }
1677 
musb_gadget_pullup(struct usb_gadget * gadget,int is_on)1678 static int musb_gadget_pullup(struct usb_gadget *gadget, int is_on)
1679 {
1680 	struct musb	*musb = gadget_to_musb(gadget);
1681 	unsigned long	flags;
1682 
1683 	is_on = !!is_on;
1684 
1685 	/* NOTE: this assumes we are sensing vbus; we'd rather
1686 	 * not pullup unless the B-session is active.
1687 	 */
1688 	spin_lock_irqsave(&musb->lock, flags);
1689 	if (is_on != musb->softconnect) {
1690 		musb->softconnect = is_on;
1691 		schedule_delayed_work(&musb->gadget_work, 0);
1692 	}
1693 	spin_unlock_irqrestore(&musb->lock, flags);
1694 
1695 	return 0;
1696 }
1697 
1698 #ifdef CONFIG_BLACKFIN
musb_match_ep(struct usb_gadget * g,struct usb_endpoint_descriptor * desc,struct usb_ss_ep_comp_descriptor * ep_comp)1699 static struct usb_ep *musb_match_ep(struct usb_gadget *g,
1700 		struct usb_endpoint_descriptor *desc,
1701 		struct usb_ss_ep_comp_descriptor *ep_comp)
1702 {
1703 	struct usb_ep *ep = NULL;
1704 
1705 	switch (usb_endpoint_type(desc)) {
1706 	case USB_ENDPOINT_XFER_ISOC:
1707 	case USB_ENDPOINT_XFER_BULK:
1708 		if (usb_endpoint_dir_in(desc))
1709 			ep = gadget_find_ep_by_name(g, "ep5in");
1710 		else
1711 			ep = gadget_find_ep_by_name(g, "ep6out");
1712 		break;
1713 	case USB_ENDPOINT_XFER_INT:
1714 		if (usb_endpoint_dir_in(desc))
1715 			ep = gadget_find_ep_by_name(g, "ep1in");
1716 		else
1717 			ep = gadget_find_ep_by_name(g, "ep2out");
1718 		break;
1719 	default:
1720 		break;
1721 	}
1722 
1723 	if (ep && usb_gadget_ep_match_desc(g, ep, desc, ep_comp))
1724 		return ep;
1725 
1726 	return NULL;
1727 }
1728 #else
1729 #define musb_match_ep NULL
1730 #endif
1731 
1732 static int musb_gadget_start(struct usb_gadget *g,
1733 		struct usb_gadget_driver *driver);
1734 static int musb_gadget_stop(struct usb_gadget *g);
1735 
1736 static const struct usb_gadget_ops musb_gadget_operations = {
1737 	.get_frame		= musb_gadget_get_frame,
1738 	.wakeup			= musb_gadget_wakeup,
1739 	.set_selfpowered	= musb_gadget_set_self_powered,
1740 	/* .vbus_session		= musb_gadget_vbus_session, */
1741 	.vbus_draw		= musb_gadget_vbus_draw,
1742 	.pullup			= musb_gadget_pullup,
1743 	.udc_start		= musb_gadget_start,
1744 	.udc_stop		= musb_gadget_stop,
1745 	.match_ep		= musb_match_ep,
1746 };
1747 
1748 /* ----------------------------------------------------------------------- */
1749 
1750 /* Registration */
1751 
1752 /* Only this registration code "knows" the rule (from USB standards)
1753  * about there being only one external upstream port.  It assumes
1754  * all peripheral ports are external...
1755  */
1756 
1757 static void
init_peripheral_ep(struct musb * musb,struct musb_ep * ep,u8 epnum,int is_in)1758 init_peripheral_ep(struct musb *musb, struct musb_ep *ep, u8 epnum, int is_in)
1759 {
1760 	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1761 
1762 	memset(ep, 0, sizeof *ep);
1763 
1764 	ep->current_epnum = epnum;
1765 	ep->musb = musb;
1766 	ep->hw_ep = hw_ep;
1767 	ep->is_in = is_in;
1768 
1769 	INIT_LIST_HEAD(&ep->req_list);
1770 
1771 	sprintf(ep->name, "ep%d%s", epnum,
1772 			(!epnum || hw_ep->is_shared_fifo) ? "" : (
1773 				is_in ? "in" : "out"));
1774 	ep->end_point.name = ep->name;
1775 	INIT_LIST_HEAD(&ep->end_point.ep_list);
1776 	if (!epnum) {
1777 		usb_ep_set_maxpacket_limit(&ep->end_point, 64);
1778 		ep->end_point.caps.type_control = true;
1779 		ep->end_point.ops = &musb_g_ep0_ops;
1780 		musb->g.ep0 = &ep->end_point;
1781 	} else {
1782 		if (is_in)
1783 			usb_ep_set_maxpacket_limit(&ep->end_point, hw_ep->max_packet_sz_tx);
1784 		else
1785 			usb_ep_set_maxpacket_limit(&ep->end_point, hw_ep->max_packet_sz_rx);
1786 		ep->end_point.caps.type_iso = true;
1787 		ep->end_point.caps.type_bulk = true;
1788 		ep->end_point.caps.type_int = true;
1789 		ep->end_point.ops = &musb_ep_ops;
1790 		list_add_tail(&ep->end_point.ep_list, &musb->g.ep_list);
1791 	}
1792 
1793 	if (!epnum || hw_ep->is_shared_fifo) {
1794 		ep->end_point.caps.dir_in = true;
1795 		ep->end_point.caps.dir_out = true;
1796 	} else if (is_in)
1797 		ep->end_point.caps.dir_in = true;
1798 	else
1799 		ep->end_point.caps.dir_out = true;
1800 }
1801 
1802 /*
1803  * Initialize the endpoints exposed to peripheral drivers, with backlinks
1804  * to the rest of the driver state.
1805  */
musb_g_init_endpoints(struct musb * musb)1806 static inline void musb_g_init_endpoints(struct musb *musb)
1807 {
1808 	u8			epnum;
1809 	struct musb_hw_ep	*hw_ep;
1810 	unsigned		count = 0;
1811 
1812 	/* initialize endpoint list just once */
1813 	INIT_LIST_HEAD(&(musb->g.ep_list));
1814 
1815 	for (epnum = 0, hw_ep = musb->endpoints;
1816 			epnum < musb->nr_endpoints;
1817 			epnum++, hw_ep++) {
1818 		if (hw_ep->is_shared_fifo /* || !epnum */) {
1819 			init_peripheral_ep(musb, &hw_ep->ep_in, epnum, 0);
1820 			count++;
1821 		} else {
1822 			if (hw_ep->max_packet_sz_tx) {
1823 				init_peripheral_ep(musb, &hw_ep->ep_in,
1824 							epnum, 1);
1825 				count++;
1826 			}
1827 			if (hw_ep->max_packet_sz_rx) {
1828 				init_peripheral_ep(musb, &hw_ep->ep_out,
1829 							epnum, 0);
1830 				count++;
1831 			}
1832 		}
1833 	}
1834 }
1835 
1836 /* called once during driver setup to initialize and link into
1837  * the driver model; memory is zeroed.
1838  */
musb_gadget_setup(struct musb * musb)1839 int musb_gadget_setup(struct musb *musb)
1840 {
1841 	int status;
1842 
1843 	/* REVISIT minor race:  if (erroneously) setting up two
1844 	 * musb peripherals at the same time, only the bus lock
1845 	 * is probably held.
1846 	 */
1847 
1848 	musb->g.ops = &musb_gadget_operations;
1849 	musb->g.max_speed = USB_SPEED_HIGH;
1850 	musb->g.speed = USB_SPEED_UNKNOWN;
1851 
1852 	MUSB_DEV_MODE(musb);
1853 	musb->xceiv->otg->default_a = 0;
1854 	musb->xceiv->otg->state = OTG_STATE_B_IDLE;
1855 
1856 	/* this "gadget" abstracts/virtualizes the controller */
1857 	musb->g.name = musb_driver_name;
1858 #if IS_ENABLED(CONFIG_USB_MUSB_DUAL_ROLE)
1859 	musb->g.is_otg = 1;
1860 #elif IS_ENABLED(CONFIG_USB_MUSB_GADGET)
1861 	musb->g.is_otg = 0;
1862 #endif
1863 	INIT_DELAYED_WORK(&musb->gadget_work, musb_gadget_work);
1864 	musb_g_init_endpoints(musb);
1865 
1866 	musb->is_active = 0;
1867 	musb_platform_try_idle(musb, 0);
1868 
1869 	status = usb_add_gadget_udc(musb->controller, &musb->g);
1870 	if (status)
1871 		goto err;
1872 
1873 	return 0;
1874 err:
1875 	musb->g.dev.parent = NULL;
1876 	device_unregister(&musb->g.dev);
1877 	return status;
1878 }
1879 
musb_gadget_cleanup(struct musb * musb)1880 void musb_gadget_cleanup(struct musb *musb)
1881 {
1882 	if (musb->port_mode == MUSB_PORT_MODE_HOST)
1883 		return;
1884 
1885 	cancel_delayed_work_sync(&musb->gadget_work);
1886 	usb_del_gadget_udc(&musb->g);
1887 }
1888 
1889 /*
1890  * Register the gadget driver. Used by gadget drivers when
1891  * registering themselves with the controller.
1892  *
1893  * -EINVAL something went wrong (not driver)
1894  * -EBUSY another gadget is already using the controller
1895  * -ENOMEM no memory to perform the operation
1896  *
1897  * @param driver the gadget driver
1898  * @return <0 if error, 0 if everything is fine
1899  */
musb_gadget_start(struct usb_gadget * g,struct usb_gadget_driver * driver)1900 static int musb_gadget_start(struct usb_gadget *g,
1901 		struct usb_gadget_driver *driver)
1902 {
1903 	struct musb		*musb = gadget_to_musb(g);
1904 	struct usb_otg		*otg = musb->xceiv->otg;
1905 	unsigned long		flags;
1906 	int			retval = 0;
1907 
1908 	if (driver->max_speed < USB_SPEED_HIGH) {
1909 		retval = -EINVAL;
1910 		goto err;
1911 	}
1912 
1913 	pm_runtime_get_sync(musb->controller);
1914 
1915 	musb->softconnect = 0;
1916 	musb->gadget_driver = driver;
1917 
1918 	spin_lock_irqsave(&musb->lock, flags);
1919 	musb->is_active = 1;
1920 
1921 	otg_set_peripheral(otg, &musb->g);
1922 	musb->xceiv->otg->state = OTG_STATE_B_IDLE;
1923 	spin_unlock_irqrestore(&musb->lock, flags);
1924 
1925 	musb_start(musb);
1926 
1927 	/* REVISIT:  funcall to other code, which also
1928 	 * handles power budgeting ... this way also
1929 	 * ensures HdrcStart is indirectly called.
1930 	 */
1931 	if (musb->xceiv->last_event == USB_EVENT_ID)
1932 		musb_platform_set_vbus(musb, 1);
1933 
1934 	pm_runtime_mark_last_busy(musb->controller);
1935 	pm_runtime_put_autosuspend(musb->controller);
1936 
1937 	return 0;
1938 
1939 err:
1940 	return retval;
1941 }
1942 
1943 /*
1944  * Unregister the gadget driver. Used by gadget drivers when
1945  * unregistering themselves from the controller.
1946  *
1947  * @param driver the gadget driver to unregister
1948  */
musb_gadget_stop(struct usb_gadget * g)1949 static int musb_gadget_stop(struct usb_gadget *g)
1950 {
1951 	struct musb	*musb = gadget_to_musb(g);
1952 	unsigned long	flags;
1953 
1954 	pm_runtime_get_sync(musb->controller);
1955 
1956 	/*
1957 	 * REVISIT always use otg_set_peripheral() here too;
1958 	 * this needs to shut down the OTG engine.
1959 	 */
1960 
1961 	spin_lock_irqsave(&musb->lock, flags);
1962 
1963 	musb_hnp_stop(musb);
1964 
1965 	(void) musb_gadget_vbus_draw(&musb->g, 0);
1966 
1967 	musb->xceiv->otg->state = OTG_STATE_UNDEFINED;
1968 	musb_stop(musb);
1969 	otg_set_peripheral(musb->xceiv->otg, NULL);
1970 
1971 	musb->is_active = 0;
1972 	musb->gadget_driver = NULL;
1973 	musb_platform_try_idle(musb, 0);
1974 	spin_unlock_irqrestore(&musb->lock, flags);
1975 
1976 	/*
1977 	 * FIXME we need to be able to register another
1978 	 * gadget driver here and have everything work;
1979 	 * that currently misbehaves.
1980 	 */
1981 
1982 	/* Force check of devctl register for PM runtime */
1983 	schedule_delayed_work(&musb->irq_work, 0);
1984 
1985 	pm_runtime_mark_last_busy(musb->controller);
1986 	pm_runtime_put_autosuspend(musb->controller);
1987 
1988 	return 0;
1989 }
1990 
1991 /* ----------------------------------------------------------------------- */
1992 
1993 /* lifecycle operations called through plat_uds.c */
1994 
musb_g_resume(struct musb * musb)1995 void musb_g_resume(struct musb *musb)
1996 {
1997 	musb->is_suspended = 0;
1998 	switch (musb->xceiv->otg->state) {
1999 	case OTG_STATE_B_IDLE:
2000 		break;
2001 	case OTG_STATE_B_WAIT_ACON:
2002 	case OTG_STATE_B_PERIPHERAL:
2003 		musb->is_active = 1;
2004 		if (musb->gadget_driver && musb->gadget_driver->resume) {
2005 			spin_unlock(&musb->lock);
2006 			musb->gadget_driver->resume(&musb->g);
2007 			spin_lock(&musb->lock);
2008 		}
2009 		break;
2010 	default:
2011 		WARNING("unhandled RESUME transition (%s)\n",
2012 				usb_otg_state_string(musb->xceiv->otg->state));
2013 	}
2014 }
2015 
2016 /* called when SOF packets stop for 3+ msec */
musb_g_suspend(struct musb * musb)2017 void musb_g_suspend(struct musb *musb)
2018 {
2019 	u8	devctl;
2020 
2021 	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
2022 	musb_dbg(musb, "musb_g_suspend: devctl %02x", devctl);
2023 
2024 	switch (musb->xceiv->otg->state) {
2025 	case OTG_STATE_B_IDLE:
2026 		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
2027 			musb->xceiv->otg->state = OTG_STATE_B_PERIPHERAL;
2028 		break;
2029 	case OTG_STATE_B_PERIPHERAL:
2030 		musb->is_suspended = 1;
2031 		if (musb->gadget_driver && musb->gadget_driver->suspend) {
2032 			spin_unlock(&musb->lock);
2033 			musb->gadget_driver->suspend(&musb->g);
2034 			spin_lock(&musb->lock);
2035 		}
2036 		break;
2037 	default:
2038 		/* REVISIT if B_HOST, clear DEVCTL.HOSTREQ;
2039 		 * A_PERIPHERAL may need care too
2040 		 */
2041 		WARNING("unhandled SUSPEND transition (%s)",
2042 				usb_otg_state_string(musb->xceiv->otg->state));
2043 	}
2044 }
2045 
2046 /* Called during SRP */
musb_g_wakeup(struct musb * musb)2047 void musb_g_wakeup(struct musb *musb)
2048 {
2049 	musb_gadget_wakeup(&musb->g);
2050 }
2051 
2052 /* called when VBUS drops below session threshold, and in other cases */
musb_g_disconnect(struct musb * musb)2053 void musb_g_disconnect(struct musb *musb)
2054 {
2055 	void __iomem	*mregs = musb->mregs;
2056 	u8	devctl = musb_readb(mregs, MUSB_DEVCTL);
2057 
2058 	musb_dbg(musb, "musb_g_disconnect: devctl %02x", devctl);
2059 
2060 	/* clear HR */
2061 	musb_writeb(mregs, MUSB_DEVCTL, devctl & MUSB_DEVCTL_SESSION);
2062 
2063 	/* don't draw vbus until new b-default session */
2064 	(void) musb_gadget_vbus_draw(&musb->g, 0);
2065 
2066 	musb->g.speed = USB_SPEED_UNKNOWN;
2067 	if (musb->gadget_driver && musb->gadget_driver->disconnect) {
2068 		spin_unlock(&musb->lock);
2069 		musb->gadget_driver->disconnect(&musb->g);
2070 		spin_lock(&musb->lock);
2071 	}
2072 
2073 	switch (musb->xceiv->otg->state) {
2074 	default:
2075 		musb_dbg(musb, "Unhandled disconnect %s, setting a_idle",
2076 			usb_otg_state_string(musb->xceiv->otg->state));
2077 		musb->xceiv->otg->state = OTG_STATE_A_IDLE;
2078 		MUSB_HST_MODE(musb);
2079 		break;
2080 	case OTG_STATE_A_PERIPHERAL:
2081 		musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
2082 		MUSB_HST_MODE(musb);
2083 		break;
2084 	case OTG_STATE_B_WAIT_ACON:
2085 	case OTG_STATE_B_HOST:
2086 	case OTG_STATE_B_PERIPHERAL:
2087 	case OTG_STATE_B_IDLE:
2088 		musb->xceiv->otg->state = OTG_STATE_B_IDLE;
2089 		break;
2090 	case OTG_STATE_B_SRP_INIT:
2091 		break;
2092 	}
2093 
2094 	musb->is_active = 0;
2095 }
2096 
musb_g_reset(struct musb * musb)2097 void musb_g_reset(struct musb *musb)
2098 __releases(musb->lock)
2099 __acquires(musb->lock)
2100 {
2101 	void __iomem	*mbase = musb->mregs;
2102 	u8		devctl = musb_readb(mbase, MUSB_DEVCTL);
2103 	u8		power;
2104 
2105 	musb_dbg(musb, "<== %s driver '%s'",
2106 			(devctl & MUSB_DEVCTL_BDEVICE)
2107 				? "B-Device" : "A-Device",
2108 			musb->gadget_driver
2109 				? musb->gadget_driver->driver.name
2110 				: NULL
2111 			);
2112 
2113 	/* report reset, if we didn't already (flushing EP state) */
2114 	if (musb->gadget_driver && musb->g.speed != USB_SPEED_UNKNOWN) {
2115 		spin_unlock(&musb->lock);
2116 		usb_gadget_udc_reset(&musb->g, musb->gadget_driver);
2117 		spin_lock(&musb->lock);
2118 	}
2119 
2120 	/* clear HR */
2121 	else if (devctl & MUSB_DEVCTL_HR)
2122 		musb_writeb(mbase, MUSB_DEVCTL, MUSB_DEVCTL_SESSION);
2123 
2124 
2125 	/* what speed did we negotiate? */
2126 	power = musb_readb(mbase, MUSB_POWER);
2127 	musb->g.speed = (power & MUSB_POWER_HSMODE)
2128 			? USB_SPEED_HIGH : USB_SPEED_FULL;
2129 
2130 	/* start in USB_STATE_DEFAULT */
2131 	musb->is_active = 1;
2132 	musb->is_suspended = 0;
2133 	MUSB_DEV_MODE(musb);
2134 	musb->address = 0;
2135 	musb->ep0_state = MUSB_EP0_STAGE_SETUP;
2136 
2137 	musb->may_wakeup = 0;
2138 	musb->g.b_hnp_enable = 0;
2139 	musb->g.a_alt_hnp_support = 0;
2140 	musb->g.a_hnp_support = 0;
2141 	musb->g.quirk_zlp_not_supp = 1;
2142 
2143 	/* Normal reset, as B-Device;
2144 	 * or else after HNP, as A-Device
2145 	 */
2146 	if (!musb->g.is_otg) {
2147 		/* USB device controllers that are not OTG compatible
2148 		 * may not have DEVCTL register in silicon.
2149 		 * In that case, do not rely on devctl for setting
2150 		 * peripheral mode.
2151 		 */
2152 		musb->xceiv->otg->state = OTG_STATE_B_PERIPHERAL;
2153 		musb->g.is_a_peripheral = 0;
2154 	} else if (devctl & MUSB_DEVCTL_BDEVICE) {
2155 		musb->xceiv->otg->state = OTG_STATE_B_PERIPHERAL;
2156 		musb->g.is_a_peripheral = 0;
2157 	} else {
2158 		musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
2159 		musb->g.is_a_peripheral = 1;
2160 	}
2161 
2162 	/* start with default limits on VBUS power draw */
2163 	(void) musb_gadget_vbus_draw(&musb->g, 8);
2164 }
2165