1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * MUSB OTG driver peripheral support
   4 *
   5 * Copyright 2005 Mentor Graphics Corporation
   6 * Copyright (C) 2005-2006 by Texas Instruments
   7 * Copyright (C) 2006-2007 Nokia Corporation
   8 * Copyright (C) 2009 MontaVista Software, Inc. <source@mvista.com>
   9 */
  10
  11#include <linux/kernel.h>
  12#include <linux/list.h>
  13#include <linux/timer.h>
  14#include <linux/module.h>
  15#include <linux/smp.h>
  16#include <linux/spinlock.h>
  17#include <linux/delay.h>
  18#include <linux/dma-mapping.h>
  19#include <linux/slab.h>
  20
  21#include "musb_core.h"
  22#include "musb_trace.h"
  23
  24
  25/* ----------------------------------------------------------------------- */
  26
  27#define is_buffer_mapped(req) (is_dma_capable() && \
  28					(req->map_state != UN_MAPPED))
  29
  30/* Maps the buffer to dma  */
  31
  32static inline void map_dma_buffer(struct musb_request *request,
  33			struct musb *musb, struct musb_ep *musb_ep)
  34{
  35	int compatible = true;
  36	struct dma_controller *dma = musb->dma_controller;
  37
  38	request->map_state = UN_MAPPED;
  39
  40	if (!is_dma_capable() || !musb_ep->dma)
  41		return;
  42
  43	/* Check if DMA engine can handle this request.
  44	 * DMA code must reject the USB request explicitly.
  45	 * Default behaviour is to map the request.
  46	 */
  47	if (dma->is_compatible)
  48		compatible = dma->is_compatible(musb_ep->dma,
  49				musb_ep->packet_sz, request->request.buf,
  50				request->request.length);
  51	if (!compatible)
  52		return;
  53
  54	if (request->request.dma == DMA_ADDR_INVALID) {
  55		dma_addr_t dma_addr;
  56		int ret;
  57
  58		dma_addr = dma_map_single(
  59				musb->controller,
  60				request->request.buf,
  61				request->request.length,
  62				request->tx
  63					? DMA_TO_DEVICE
  64					: DMA_FROM_DEVICE);
  65		ret = dma_mapping_error(musb->controller, dma_addr);
  66		if (ret)
  67			return;
  68
  69		request->request.dma = dma_addr;
  70		request->map_state = MUSB_MAPPED;
  71	} else {
  72		dma_sync_single_for_device(musb->controller,
  73			request->request.dma,
  74			request->request.length,
  75			request->tx
  76				? DMA_TO_DEVICE
  77				: DMA_FROM_DEVICE);
  78		request->map_state = PRE_MAPPED;
  79	}
  80}
  81
  82/* Unmap the buffer from dma and maps it back to cpu */
  83static inline void unmap_dma_buffer(struct musb_request *request,
  84				struct musb *musb)
  85{
  86	struct musb_ep *musb_ep = request->ep;
  87
  88	if (!is_buffer_mapped(request) || !musb_ep->dma)
  89		return;
  90
  91	if (request->request.dma == DMA_ADDR_INVALID) {
  92		dev_vdbg(musb->controller,
  93				"not unmapping a never mapped buffer\n");
  94		return;
  95	}
  96	if (request->map_state == MUSB_MAPPED) {
  97		dma_unmap_single(musb->controller,
  98			request->request.dma,
  99			request->request.length,
 100			request->tx
 101				? DMA_TO_DEVICE
 102				: DMA_FROM_DEVICE);
 103		request->request.dma = DMA_ADDR_INVALID;
 104	} else { /* PRE_MAPPED */
 105		dma_sync_single_for_cpu(musb->controller,
 106			request->request.dma,
 107			request->request.length,
 108			request->tx
 109				? DMA_TO_DEVICE
 110				: DMA_FROM_DEVICE);
 111	}
 112	request->map_state = UN_MAPPED;
 113}
 114
 115/*
 116 * Immediately complete a request.
 117 *
 118 * @param request the request to complete
 119 * @param status the status to complete the request with
 120 * Context: controller locked, IRQs blocked.
 121 */
 122void musb_g_giveback(
 123	struct musb_ep		*ep,
 124	struct usb_request	*request,
 125	int			status)
 126__releases(ep->musb->lock)
 127__acquires(ep->musb->lock)
 128{
 129	struct musb_request	*req;
 130	struct musb		*musb;
 131	int			busy = ep->busy;
 132
 133	req = to_musb_request(request);
 134
 135	list_del(&req->list);
 136	if (req->request.status == -EINPROGRESS)
 137		req->request.status = status;
 138	musb = req->musb;
 139
 140	ep->busy = 1;
 141	spin_unlock(&musb->lock);
 142
 143	if (!dma_mapping_error(&musb->g.dev, request->dma))
 144		unmap_dma_buffer(req, musb);
 145
 146	trace_musb_req_gb(req);
 147	usb_gadget_giveback_request(&req->ep->end_point, &req->request);
 148	spin_lock(&musb->lock);
 149	ep->busy = busy;
 150}
 151
 152/* ----------------------------------------------------------------------- */
 153
 154/*
 155 * Abort requests queued to an endpoint using the status. Synchronous.
 156 * caller locked controller and blocked irqs, and selected this ep.
 157 */
 158static void nuke(struct musb_ep *ep, const int status)
 159{
 160	struct musb		*musb = ep->musb;
 161	struct musb_request	*req = NULL;
 162	void __iomem *epio = ep->musb->endpoints[ep->current_epnum].regs;
 163
 164	ep->busy = 1;
 165
 166	if (is_dma_capable() && ep->dma) {
 167		struct dma_controller	*c = ep->musb->dma_controller;
 168		int value;
 169
 170		if (ep->is_in) {
 171			/*
 172			 * The programming guide says that we must not clear
 173			 * the DMAMODE bit before DMAENAB, so we only
 174			 * clear it in the second write...
 175			 */
 176			musb_writew(epio, MUSB_TXCSR,
 177				    MUSB_TXCSR_DMAMODE | MUSB_TXCSR_FLUSHFIFO);
 178			musb_writew(epio, MUSB_TXCSR,
 179					0 | MUSB_TXCSR_FLUSHFIFO);
 180		} else {
 181			musb_writew(epio, MUSB_RXCSR,
 182					0 | MUSB_RXCSR_FLUSHFIFO);
 183			musb_writew(epio, MUSB_RXCSR,
 184					0 | MUSB_RXCSR_FLUSHFIFO);
 185		}
 186
 187		value = c->channel_abort(ep->dma);
 188		musb_dbg(musb, "%s: abort DMA --> %d", ep->name, value);
 189		c->channel_release(ep->dma);
 190		ep->dma = NULL;
 191	}
 192
 193	while (!list_empty(&ep->req_list)) {
 194		req = list_first_entry(&ep->req_list, struct musb_request, list);
 195		musb_g_giveback(ep, &req->request, status);
 196	}
 197}
 198
 199/* ----------------------------------------------------------------------- */
 200
 201/* Data transfers - pure PIO, pure DMA, or mixed mode */
 202
 203/*
 204 * This assumes the separate CPPI engine is responding to DMA requests
 205 * from the usb core ... sequenced a bit differently from mentor dma.
 206 */
 207
 208static inline int max_ep_writesize(struct musb *musb, struct musb_ep *ep)
 209{
 210	if (can_bulk_split(musb, ep->type))
 211		return ep->hw_ep->max_packet_sz_tx;
 212	else
 213		return ep->packet_sz;
 214}
 215
 216/*
 217 * An endpoint is transmitting data. This can be called either from
 218 * the IRQ routine or from ep.queue() to kickstart a request on an
 219 * endpoint.
 220 *
 221 * Context: controller locked, IRQs blocked, endpoint selected
 222 */
 223static void txstate(struct musb *musb, struct musb_request *req)
 224{
 225	u8			epnum = req->epnum;
 226	struct musb_ep		*musb_ep;
 227	void __iomem		*epio = musb->endpoints[epnum].regs;
 228	struct usb_request	*request;
 229	u16			fifo_count = 0, csr;
 230	int			use_dma = 0;
 231
 232	musb_ep = req->ep;
 233
 234	/* Check if EP is disabled */
 235	if (!musb_ep->desc) {
 236		musb_dbg(musb, "ep:%s disabled - ignore request",
 237						musb_ep->end_point.name);
 238		return;
 239	}
 240
 241	/* we shouldn't get here while DMA is active ... but we do ... */
 242	if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) {
 243		musb_dbg(musb, "dma pending...");
 244		return;
 245	}
 246
 247	/* read TXCSR before */
 248	csr = musb_readw(epio, MUSB_TXCSR);
 249
 250	request = &req->request;
 251	fifo_count = min(max_ep_writesize(musb, musb_ep),
 252			(int)(request->length - request->actual));
 253
 254	if (csr & MUSB_TXCSR_TXPKTRDY) {
 255		musb_dbg(musb, "%s old packet still ready , txcsr %03x",
 256				musb_ep->end_point.name, csr);
 257		return;
 258	}
 259
 260	if (csr & MUSB_TXCSR_P_SENDSTALL) {
 261		musb_dbg(musb, "%s stalling, txcsr %03x",
 262				musb_ep->end_point.name, csr);
 263		return;
 264	}
 265
 266	musb_dbg(musb, "hw_ep%d, maxpacket %d, fifo count %d, txcsr %03x",
 267			epnum, musb_ep->packet_sz, fifo_count,
 268			csr);
 269
 270#ifndef	CONFIG_MUSB_PIO_ONLY
 271	if (is_buffer_mapped(req)) {
 272		struct dma_controller	*c = musb->dma_controller;
 273		size_t request_size;
 274
 275		/* setup DMA, then program endpoint CSR */
 276		request_size = min_t(size_t, request->length - request->actual,
 277					musb_ep->dma->max_len);
 278
 279		use_dma = (request->dma != DMA_ADDR_INVALID && request_size);
 280
 281		/* MUSB_TXCSR_P_ISO is still set correctly */
 282
 283		if (musb_dma_inventra(musb) || musb_dma_ux500(musb)) {
 284			if (request_size < musb_ep->packet_sz)
 285				musb_ep->dma->desired_mode = 0;
 286			else
 287				musb_ep->dma->desired_mode = 1;
 288
 289			use_dma = use_dma && c->channel_program(
 290					musb_ep->dma, musb_ep->packet_sz,
 291					musb_ep->dma->desired_mode,
 292					request->dma + request->actual, request_size);
 293			if (use_dma) {
 294				if (musb_ep->dma->desired_mode == 0) {
 295					/*
 296					 * We must not clear the DMAMODE bit
 297					 * before the DMAENAB bit -- and the
 298					 * latter doesn't always get cleared
 299					 * before we get here...
 300					 */
 301					csr &= ~(MUSB_TXCSR_AUTOSET
 302						| MUSB_TXCSR_DMAENAB);
 303					musb_writew(epio, MUSB_TXCSR, csr
 304						| MUSB_TXCSR_P_WZC_BITS);
 305					csr &= ~MUSB_TXCSR_DMAMODE;
 306					csr |= (MUSB_TXCSR_DMAENAB |
 307							MUSB_TXCSR_MODE);
 308					/* against programming guide */
 309				} else {
 310					csr |= (MUSB_TXCSR_DMAENAB
 311							| MUSB_TXCSR_DMAMODE
 312							| MUSB_TXCSR_MODE);
 313					/*
 314					 * Enable Autoset according to table
 315					 * below
 316					 * bulk_split hb_mult	Autoset_Enable
 317					 *	0	0	Yes(Normal)
 318					 *	0	>0	No(High BW ISO)
 319					 *	1	0	Yes(HS bulk)
 320					 *	1	>0	Yes(FS bulk)
 321					 */
 322					if (!musb_ep->hb_mult ||
 323					    can_bulk_split(musb,
 324							   musb_ep->type))
 325						csr |= MUSB_TXCSR_AUTOSET;
 326				}
 327				csr &= ~MUSB_TXCSR_P_UNDERRUN;
 328
 329				musb_writew(epio, MUSB_TXCSR, csr);
 330			}
 331		}
 332
 333		if (is_cppi_enabled(musb)) {
 334			/* program endpoint CSR first, then setup DMA */
 335			csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
 336			csr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_DMAMODE |
 337				MUSB_TXCSR_MODE;
 338			musb_writew(epio, MUSB_TXCSR, (MUSB_TXCSR_P_WZC_BITS &
 339						~MUSB_TXCSR_P_UNDERRUN) | csr);
 340
 341			/* ensure writebuffer is empty */
 342			csr = musb_readw(epio, MUSB_TXCSR);
 343
 344			/*
 345			 * NOTE host side sets DMAENAB later than this; both are
 346			 * OK since the transfer dma glue (between CPPI and
 347			 * Mentor fifos) just tells CPPI it could start. Data
 348			 * only moves to the USB TX fifo when both fifos are
 349			 * ready.
 350			 */
 351			/*
 352			 * "mode" is irrelevant here; handle terminating ZLPs
 353			 * like PIO does, since the hardware RNDIS mode seems
 354			 * unreliable except for the
 355			 * last-packet-is-already-short case.
 356			 */
 357			use_dma = use_dma && c->channel_program(
 358					musb_ep->dma, musb_ep->packet_sz,
 359					0,
 360					request->dma + request->actual,
 361					request_size);
 362			if (!use_dma) {
 363				c->channel_release(musb_ep->dma);
 364				musb_ep->dma = NULL;
 365				csr &= ~MUSB_TXCSR_DMAENAB;
 366				musb_writew(epio, MUSB_TXCSR, csr);
 367				/* invariant: prequest->buf is non-null */
 368			}
 369		} else if (tusb_dma_omap(musb))
 370			use_dma = use_dma && c->channel_program(
 371					musb_ep->dma, musb_ep->packet_sz,
 372					request->zero,
 373					request->dma + request->actual,
 374					request_size);
 375	}
 376#endif
 377
 378	if (!use_dma) {
 379		/*
 380		 * Unmap the dma buffer back to cpu if dma channel
 381		 * programming fails
 382		 */
 383		unmap_dma_buffer(req, musb);
 384
 385		musb_write_fifo(musb_ep->hw_ep, fifo_count,
 386				(u8 *) (request->buf + request->actual));
 387		request->actual += fifo_count;
 388		csr |= MUSB_TXCSR_TXPKTRDY;
 389		csr &= ~MUSB_TXCSR_P_UNDERRUN;
 390		musb_writew(epio, MUSB_TXCSR, csr);
 391	}
 392
 393	/* host may already have the data when this message shows... */
 394	musb_dbg(musb, "%s TX/IN %s len %d/%d, txcsr %04x, fifo %d/%d",
 395			musb_ep->end_point.name, use_dma ? "dma" : "pio",
 396			request->actual, request->length,
 397			musb_readw(epio, MUSB_TXCSR),
 398			fifo_count,
 399			musb_readw(epio, MUSB_TXMAXP));
 400}
 401
 402/*
 403 * FIFO state update (e.g. data ready).
 404 * Called from IRQ,  with controller locked.
 405 */
 406void musb_g_tx(struct musb *musb, u8 epnum)
 407{
 408	u16			csr;
 409	struct musb_request	*req;
 410	struct usb_request	*request;
 411	u8 __iomem		*mbase = musb->mregs;
 412	struct musb_ep		*musb_ep = &musb->endpoints[epnum].ep_in;
 413	void __iomem		*epio = musb->endpoints[epnum].regs;
 414	struct dma_channel	*dma;
 415
 416	musb_ep_select(mbase, epnum);
 417	req = next_request(musb_ep);
 418	request = &req->request;
 419
 420	csr = musb_readw(epio, MUSB_TXCSR);
 421	musb_dbg(musb, "<== %s, txcsr %04x", musb_ep->end_point.name, csr);
 422
 423	dma = is_dma_capable() ? musb_ep->dma : NULL;
 424
 425	/*
 426	 * REVISIT: for high bandwidth, MUSB_TXCSR_P_INCOMPTX
 427	 * probably rates reporting as a host error.
 428	 */
 429	if (csr & MUSB_TXCSR_P_SENTSTALL) {
 430		csr |=	MUSB_TXCSR_P_WZC_BITS;
 431		csr &= ~MUSB_TXCSR_P_SENTSTALL;
 432		musb_writew(epio, MUSB_TXCSR, csr);
 433		return;
 434	}
 435
 436	if (csr & MUSB_TXCSR_P_UNDERRUN) {
 437		/* We NAKed, no big deal... little reason to care. */
 438		csr |=	 MUSB_TXCSR_P_WZC_BITS;
 439		csr &= ~(MUSB_TXCSR_P_UNDERRUN | MUSB_TXCSR_TXPKTRDY);
 440		musb_writew(epio, MUSB_TXCSR, csr);
 441		dev_vdbg(musb->controller, "underrun on ep%d, req %p\n",
 442				epnum, request);
 443	}
 444
 445	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
 446		/*
 447		 * SHOULD NOT HAPPEN... has with CPPI though, after
 448		 * changing SENDSTALL (and other cases); harmless?
 449		 */
 450		musb_dbg(musb, "%s dma still busy?", musb_ep->end_point.name);
 451		return;
 452	}
 453
 454	if (req) {
 455
 456		trace_musb_req_tx(req);
 457
 458		if (dma && (csr & MUSB_TXCSR_DMAENAB)) {
 459			csr |= MUSB_TXCSR_P_WZC_BITS;
 460			csr &= ~(MUSB_TXCSR_DMAENAB | MUSB_TXCSR_P_UNDERRUN |
 461				 MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_AUTOSET);
 462			musb_writew(epio, MUSB_TXCSR, csr);
 463			/* Ensure writebuffer is empty. */
 464			csr = musb_readw(epio, MUSB_TXCSR);
 465			request->actual += musb_ep->dma->actual_len;
 466			musb_dbg(musb, "TXCSR%d %04x, DMA off, len %zu, req %p",
 467				epnum, csr, musb_ep->dma->actual_len, request);
 468		}
 469
 470		/*
 471		 * First, maybe a terminating short packet. Some DMA
 472		 * engines might handle this by themselves.
 473		 */
 474		if ((request->zero && request->length)
 475			&& (request->length % musb_ep->packet_sz == 0)
 476			&& (request->actual == request->length)) {
 477
 478			/*
 479			 * On DMA completion, FIFO may not be
 480			 * available yet...
 481			 */
 482			if (csr & MUSB_TXCSR_TXPKTRDY)
 483				return;
 484
 485			musb_writew(epio, MUSB_TXCSR, MUSB_TXCSR_MODE
 486					| MUSB_TXCSR_TXPKTRDY);
 487			request->zero = 0;
 488		}
 489
 490		if (request->actual == request->length) {
 491			musb_g_giveback(musb_ep, request, 0);
 492			/*
 493			 * In the giveback function the MUSB lock is
 494			 * released and acquired after sometime. During
 495			 * this time period the INDEX register could get
 496			 * changed by the gadget_queue function especially
 497			 * on SMP systems. Reselect the INDEX to be sure
 498			 * we are reading/modifying the right registers
 499			 */
 500			musb_ep_select(mbase, epnum);
 501			req = musb_ep->desc ? next_request(musb_ep) : NULL;
 502			if (!req) {
 503				musb_dbg(musb, "%s idle now",
 504					musb_ep->end_point.name);
 505				return;
 506			}
 507		}
 508
 509		txstate(musb, req);
 510	}
 511}
 512
 513/* ------------------------------------------------------------ */
 514
 515/*
 516 * Context: controller locked, IRQs blocked, endpoint selected
 517 */
 518static void rxstate(struct musb *musb, struct musb_request *req)
 519{
 520	const u8		epnum = req->epnum;
 521	struct usb_request	*request = &req->request;
 522	struct musb_ep		*musb_ep;
 523	void __iomem		*epio = musb->endpoints[epnum].regs;
 524	unsigned		len = 0;
 525	u16			fifo_count;
 526	u16			csr = musb_readw(epio, MUSB_RXCSR);
 527	struct musb_hw_ep	*hw_ep = &musb->endpoints[epnum];
 528	u8			use_mode_1;
 529
 530	if (hw_ep->is_shared_fifo)
 531		musb_ep = &hw_ep->ep_in;
 532	else
 533		musb_ep = &hw_ep->ep_out;
 534
 535	fifo_count = musb_ep->packet_sz;
 536
 537	/* Check if EP is disabled */
 538	if (!musb_ep->desc) {
 539		musb_dbg(musb, "ep:%s disabled - ignore request",
 540						musb_ep->end_point.name);
 541		return;
 542	}
 543
 544	/* We shouldn't get here while DMA is active, but we do... */
 545	if (dma_channel_status(musb_ep->dma) == MUSB_DMA_STATUS_BUSY) {
 546		musb_dbg(musb, "DMA pending...");
 547		return;
 548	}
 549
 550	if (csr & MUSB_RXCSR_P_SENDSTALL) {
 551		musb_dbg(musb, "%s stalling, RXCSR %04x",
 552		    musb_ep->end_point.name, csr);
 553		return;
 554	}
 555
 556	if (is_cppi_enabled(musb) && is_buffer_mapped(req)) {
 557		struct dma_controller	*c = musb->dma_controller;
 558		struct dma_channel	*channel = musb_ep->dma;
 559
 560		/* NOTE:  CPPI won't actually stop advancing the DMA
 561		 * queue after short packet transfers, so this is almost
 562		 * always going to run as IRQ-per-packet DMA so that
 563		 * faults will be handled correctly.
 564		 */
 565		if (c->channel_program(channel,
 566				musb_ep->packet_sz,
 567				!request->short_not_ok,
 568				request->dma + request->actual,
 569				request->length - request->actual)) {
 570
 571			/* make sure that if an rxpkt arrived after the irq,
 572			 * the cppi engine will be ready to take it as soon
 573			 * as DMA is enabled
 574			 */
 575			csr &= ~(MUSB_RXCSR_AUTOCLEAR
 576					| MUSB_RXCSR_DMAMODE);
 577			csr |= MUSB_RXCSR_DMAENAB | MUSB_RXCSR_P_WZC_BITS;
 578			musb_writew(epio, MUSB_RXCSR, csr);
 579			return;
 580		}
 581	}
 582
 583	if (csr & MUSB_RXCSR_RXPKTRDY) {
 584		fifo_count = musb_readw(epio, MUSB_RXCOUNT);
 585
 586		/*
 587		 * Enable Mode 1 on RX transfers only when short_not_ok flag
 588		 * is set. Currently short_not_ok flag is set only from
 589		 * file_storage and f_mass_storage drivers
 590		 */
 591
 592		if (request->short_not_ok && fifo_count == musb_ep->packet_sz)
 593			use_mode_1 = 1;
 594		else
 595			use_mode_1 = 0;
 596
 597		if (request->actual < request->length) {
 598			if (!is_buffer_mapped(req))
 599				goto buffer_aint_mapped;
 600
 601			if (musb_dma_inventra(musb)) {
 602				struct dma_controller	*c;
 603				struct dma_channel	*channel;
 604				int			use_dma = 0;
 605				unsigned int transfer_size;
 606
 607				c = musb->dma_controller;
 608				channel = musb_ep->dma;
 609
 610	/* We use DMA Req mode 0 in rx_csr, and DMA controller operates in
 611	 * mode 0 only. So we do not get endpoint interrupts due to DMA
 612	 * completion. We only get interrupts from DMA controller.
 613	 *
 614	 * We could operate in DMA mode 1 if we knew the size of the transfer
 615	 * in advance. For mass storage class, request->length = what the host
 616	 * sends, so that'd work.  But for pretty much everything else,
 617	 * request->length is routinely more than what the host sends. For
 618	 * most these gadgets, end of is signified either by a short packet,
 619	 * or filling the last byte of the buffer.  (Sending extra data in
 620	 * that last pckate should trigger an overflow fault.)  But in mode 1,
 621	 * we don't get DMA completion interrupt for short packets.
 622	 *
 623	 * Theoretically, we could enable DMAReq irq (MUSB_RXCSR_DMAMODE = 1),
 624	 * to get endpoint interrupt on every DMA req, but that didn't seem
 625	 * to work reliably.
 626	 *
 627	 * REVISIT an updated g_file_storage can set req->short_not_ok, which
 628	 * then becomes usable as a runtime "use mode 1" hint...
 629	 */
 630
 631				/* Experimental: Mode1 works with mass storage use cases */
 632				if (use_mode_1) {
 633					csr |= MUSB_RXCSR_AUTOCLEAR;
 634					musb_writew(epio, MUSB_RXCSR, csr);
 635					csr |= MUSB_RXCSR_DMAENAB;
 636					musb_writew(epio, MUSB_RXCSR, csr);
 637
 638					/*
 639					 * this special sequence (enabling and then
 640					 * disabling MUSB_RXCSR_DMAMODE) is required
 641					 * to get DMAReq to activate
 642					 */
 643					musb_writew(epio, MUSB_RXCSR,
 644						csr | MUSB_RXCSR_DMAMODE);
 645					musb_writew(epio, MUSB_RXCSR, csr);
 646
 647					transfer_size = min_t(unsigned int,
 648							request->length -
 649							request->actual,
 650							channel->max_len);
 651					musb_ep->dma->desired_mode = 1;
 652				} else {
 653					if (!musb_ep->hb_mult &&
 654						musb_ep->hw_ep->rx_double_buffered)
 655						csr |= MUSB_RXCSR_AUTOCLEAR;
 656					csr |= MUSB_RXCSR_DMAENAB;
 657					musb_writew(epio, MUSB_RXCSR, csr);
 658
 659					transfer_size = min(request->length - request->actual,
 660							(unsigned)fifo_count);
 661					musb_ep->dma->desired_mode = 0;
 662				}
 663
 664				use_dma = c->channel_program(
 665						channel,
 666						musb_ep->packet_sz,
 667						channel->desired_mode,
 668						request->dma
 669						+ request->actual,
 670						transfer_size);
 671
 672				if (use_dma)
 673					return;
 674			}
 675
 676			if ((musb_dma_ux500(musb)) &&
 677				(request->actual < request->length)) {
 678
 679				struct dma_controller *c;
 680				struct dma_channel *channel;
 681				unsigned int transfer_size = 0;
 682
 683				c = musb->dma_controller;
 684				channel = musb_ep->dma;
 685
 686				/* In case first packet is short */
 687				if (fifo_count < musb_ep->packet_sz)
 688					transfer_size = fifo_count;
 689				else if (request->short_not_ok)
 690					transfer_size =	min_t(unsigned int,
 691							request->length -
 692							request->actual,
 693							channel->max_len);
 694				else
 695					transfer_size = min_t(unsigned int,
 696							request->length -
 697							request->actual,
 698							(unsigned)fifo_count);
 699
 700				csr &= ~MUSB_RXCSR_DMAMODE;
 701				csr |= (MUSB_RXCSR_DMAENAB |
 702					MUSB_RXCSR_AUTOCLEAR);
 703
 704				musb_writew(epio, MUSB_RXCSR, csr);
 705
 706				if (transfer_size <= musb_ep->packet_sz) {
 707					musb_ep->dma->desired_mode = 0;
 708				} else {
 709					musb_ep->dma->desired_mode = 1;
 710					/* Mode must be set after DMAENAB */
 711					csr |= MUSB_RXCSR_DMAMODE;
 712					musb_writew(epio, MUSB_RXCSR, csr);
 713				}
 714
 715				if (c->channel_program(channel,
 716							musb_ep->packet_sz,
 717							channel->desired_mode,
 718							request->dma
 719							+ request->actual,
 720							transfer_size))
 721
 722					return;
 723			}
 724
 725			len = request->length - request->actual;
 726			musb_dbg(musb, "%s OUT/RX pio fifo %d/%d, maxpacket %d",
 727					musb_ep->end_point.name,
 728					fifo_count, len,
 729					musb_ep->packet_sz);
 730
 731			fifo_count = min_t(unsigned, len, fifo_count);
 732
 733			if (tusb_dma_omap(musb)) {
 734				struct dma_controller *c = musb->dma_controller;
 735				struct dma_channel *channel = musb_ep->dma;
 736				u32 dma_addr = request->dma + request->actual;
 737				int ret;
 738
 739				ret = c->channel_program(channel,
 740						musb_ep->packet_sz,
 741						channel->desired_mode,
 742						dma_addr,
 743						fifo_count);
 744				if (ret)
 745					return;
 746			}
 747
 748			/*
 749			 * Unmap the dma buffer back to cpu if dma channel
 750			 * programming fails. This buffer is mapped if the
 751			 * channel allocation is successful
 752			 */
 753			unmap_dma_buffer(req, musb);
 754
 755			/*
 756			 * Clear DMAENAB and AUTOCLEAR for the
 757			 * PIO mode transfer
 758			 */
 759			csr &= ~(MUSB_RXCSR_DMAENAB | MUSB_RXCSR_AUTOCLEAR);
 760			musb_writew(epio, MUSB_RXCSR, csr);
 761
 762buffer_aint_mapped:
 763			fifo_count = min_t(unsigned int,
 764					request->length - request->actual,
 765					(unsigned int)fifo_count);
 766			musb_read_fifo(musb_ep->hw_ep, fifo_count, (u8 *)
 767					(request->buf + request->actual));
 768			request->actual += fifo_count;
 769
 770			/* REVISIT if we left anything in the fifo, flush
 771			 * it and report -EOVERFLOW
 772			 */
 773
 774			/* ack the read! */
 775			csr |= MUSB_RXCSR_P_WZC_BITS;
 776			csr &= ~MUSB_RXCSR_RXPKTRDY;
 777			musb_writew(epio, MUSB_RXCSR, csr);
 778		}
 779	}
 780
 781	/* reach the end or short packet detected */
 782	if (request->actual == request->length ||
 783	    fifo_count < musb_ep->packet_sz)
 784		musb_g_giveback(musb_ep, request, 0);
 785}
 786
 787/*
 788 * Data ready for a request; called from IRQ
 789 */
 790void musb_g_rx(struct musb *musb, u8 epnum)
 791{
 792	u16			csr;
 793	struct musb_request	*req;
 794	struct usb_request	*request;
 795	void __iomem		*mbase = musb->mregs;
 796	struct musb_ep		*musb_ep;
 797	void __iomem		*epio = musb->endpoints[epnum].regs;
 798	struct dma_channel	*dma;
 799	struct musb_hw_ep	*hw_ep = &musb->endpoints[epnum];
 800
 801	if (hw_ep->is_shared_fifo)
 802		musb_ep = &hw_ep->ep_in;
 803	else
 804		musb_ep = &hw_ep->ep_out;
 805
 806	musb_ep_select(mbase, epnum);
 807
 808	req = next_request(musb_ep);
 809	if (!req)
 810		return;
 811
 812	trace_musb_req_rx(req);
 813	request = &req->request;
 814
 815	csr = musb_readw(epio, MUSB_RXCSR);
 816	dma = is_dma_capable() ? musb_ep->dma : NULL;
 817
 818	musb_dbg(musb, "<== %s, rxcsr %04x%s %p", musb_ep->end_point.name,
 819			csr, dma ? " (dma)" : "", request);
 820
 821	if (csr & MUSB_RXCSR_P_SENTSTALL) {
 822		csr |= MUSB_RXCSR_P_WZC_BITS;
 823		csr &= ~MUSB_RXCSR_P_SENTSTALL;
 824		musb_writew(epio, MUSB_RXCSR, csr);
 825		return;
 826	}
 827
 828	if (csr & MUSB_RXCSR_P_OVERRUN) {
 829		/* csr |= MUSB_RXCSR_P_WZC_BITS; */
 830		csr &= ~MUSB_RXCSR_P_OVERRUN;
 831		musb_writew(epio, MUSB_RXCSR, csr);
 832
 833		musb_dbg(musb, "%s iso overrun on %p", musb_ep->name, request);
 834		if (request->status == -EINPROGRESS)
 835			request->status = -EOVERFLOW;
 836	}
 837	if (csr & MUSB_RXCSR_INCOMPRX) {
 838		/* REVISIT not necessarily an error */
 839		musb_dbg(musb, "%s, incomprx", musb_ep->end_point.name);
 840	}
 841
 842	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
 843		/* "should not happen"; likely RXPKTRDY pending for DMA */
 844		musb_dbg(musb, "%s busy, csr %04x",
 845			musb_ep->end_point.name, csr);
 846		return;
 847	}
 848
 849	if (dma && (csr & MUSB_RXCSR_DMAENAB)) {
 850		csr &= ~(MUSB_RXCSR_AUTOCLEAR
 851				| MUSB_RXCSR_DMAENAB
 852				| MUSB_RXCSR_DMAMODE);
 853		musb_writew(epio, MUSB_RXCSR,
 854			MUSB_RXCSR_P_WZC_BITS | csr);
 855
 856		request->actual += musb_ep->dma->actual_len;
 857
 858#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_TUSB_OMAP_DMA) || \
 859	defined(CONFIG_USB_UX500_DMA)
 860		/* Autoclear doesn't clear RxPktRdy for short packets */
 861		if ((dma->desired_mode == 0 && !hw_ep->rx_double_buffered)
 862				|| (dma->actual_len
 863					& (musb_ep->packet_sz - 1))) {
 864			/* ack the read! */
 865			csr &= ~MUSB_RXCSR_RXPKTRDY;
 866			musb_writew(epio, MUSB_RXCSR, csr);
 867		}
 868
 869		/* incomplete, and not short? wait for next IN packet */
 870		if ((request->actual < request->length)
 871				&& (musb_ep->dma->actual_len
 872					== musb_ep->packet_sz)) {
 873			/* In double buffer case, continue to unload fifo if
 874 			 * there is Rx packet in FIFO.
 875 			 **/
 876			csr = musb_readw(epio, MUSB_RXCSR);
 877			if ((csr & MUSB_RXCSR_RXPKTRDY) &&
 878				hw_ep->rx_double_buffered)
 879				goto exit;
 880			return;
 881		}
 882#endif
 883		musb_g_giveback(musb_ep, request, 0);
 884		/*
 885		 * In the giveback function the MUSB lock is
 886		 * released and acquired after sometime. During
 887		 * this time period the INDEX register could get
 888		 * changed by the gadget_queue function especially
 889		 * on SMP systems. Reselect the INDEX to be sure
 890		 * we are reading/modifying the right registers
 891		 */
 892		musb_ep_select(mbase, epnum);
 893
 894		req = next_request(musb_ep);
 895		if (!req)
 896			return;
 897	}
 898#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_TUSB_OMAP_DMA) || \
 899	defined(CONFIG_USB_UX500_DMA)
 900exit:
 901#endif
 902	/* Analyze request */
 903	rxstate(musb, req);
 904}
 905
 906/* ------------------------------------------------------------ */
 907
 908static int musb_gadget_enable(struct usb_ep *ep,
 909			const struct usb_endpoint_descriptor *desc)
 910{
 911	unsigned long		flags;
 912	struct musb_ep		*musb_ep;
 913	struct musb_hw_ep	*hw_ep;
 914	void __iomem		*regs;
 915	struct musb		*musb;
 916	void __iomem	*mbase;
 917	u8		epnum;
 918	u16		csr;
 919	unsigned	tmp;
 920	int		status = -EINVAL;
 921
 922	if (!ep || !desc)
 923		return -EINVAL;
 924
 925	musb_ep = to_musb_ep(ep);
 926	hw_ep = musb_ep->hw_ep;
 927	regs = hw_ep->regs;
 928	musb = musb_ep->musb;
 929	mbase = musb->mregs;
 930	epnum = musb_ep->current_epnum;
 931
 932	spin_lock_irqsave(&musb->lock, flags);
 933
 934	if (musb_ep->desc) {
 935		status = -EBUSY;
 936		goto fail;
 937	}
 938	musb_ep->type = usb_endpoint_type(desc);
 939
 940	/* check direction and (later) maxpacket size against endpoint */
 941	if (usb_endpoint_num(desc) != epnum)
 942		goto fail;
 943
 944	/* REVISIT this rules out high bandwidth periodic transfers */
 945	tmp = usb_endpoint_maxp_mult(desc) - 1;
 946	if (tmp) {
 947		int ok;
 948
 949		if (usb_endpoint_dir_in(desc))
 950			ok = musb->hb_iso_tx;
 951		else
 952			ok = musb->hb_iso_rx;
 953
 954		if (!ok) {
 955			musb_dbg(musb, "no support for high bandwidth ISO");
 956			goto fail;
 957		}
 958		musb_ep->hb_mult = tmp;
 959	} else {
 960		musb_ep->hb_mult = 0;
 961	}
 962
 963	musb_ep->packet_sz = usb_endpoint_maxp(desc);
 964	tmp = musb_ep->packet_sz * (musb_ep->hb_mult + 1);
 965
 966	/* enable the interrupts for the endpoint, set the endpoint
 967	 * packet size (or fail), set the mode, clear the fifo
 968	 */
 969	musb_ep_select(mbase, epnum);
 970	if (usb_endpoint_dir_in(desc)) {
 971
 972		if (hw_ep->is_shared_fifo)
 973			musb_ep->is_in = 1;
 974		if (!musb_ep->is_in)
 975			goto fail;
 976
 977		if (tmp > hw_ep->max_packet_sz_tx) {
 978			musb_dbg(musb, "packet size beyond hardware FIFO size");
 979			goto fail;
 980		}
 981
 982		musb->intrtxe |= (1 << epnum);
 983		musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe);
 984
 985		/* REVISIT if can_bulk_split(), use by updating "tmp";
 986		 * likewise high bandwidth periodic tx
 987		 */
 988		/* Set TXMAXP with the FIFO size of the endpoint
 989		 * to disable double buffering mode.
 990		 */
 991		if (can_bulk_split(musb, musb_ep->type))
 992			musb_ep->hb_mult = (hw_ep->max_packet_sz_tx /
 993						musb_ep->packet_sz) - 1;
 994		musb_writew(regs, MUSB_TXMAXP, musb_ep->packet_sz
 995				| (musb_ep->hb_mult << 11));
 996
 997		csr = MUSB_TXCSR_MODE | MUSB_TXCSR_CLRDATATOG;
 998		if (musb_readw(regs, MUSB_TXCSR)
 999				& MUSB_TXCSR_FIFONOTEMPTY)
1000			csr |= MUSB_TXCSR_FLUSHFIFO;
1001		if (musb_ep->type == USB_ENDPOINT_XFER_ISOC)
1002			csr |= MUSB_TXCSR_P_ISO;
1003
1004		/* set twice in case of double buffering */
1005		musb_writew(regs, MUSB_TXCSR, csr);
1006		/* REVISIT may be inappropriate w/o FIFONOTEMPTY ... */
1007		musb_writew(regs, MUSB_TXCSR, csr);
1008
1009	} else {
1010
1011		if (hw_ep->is_shared_fifo)
1012			musb_ep->is_in = 0;
1013		if (musb_ep->is_in)
1014			goto fail;
1015
1016		if (tmp > hw_ep->max_packet_sz_rx) {
1017			musb_dbg(musb, "packet size beyond hardware FIFO size");
1018			goto fail;
1019		}
1020
1021		musb->intrrxe |= (1 << epnum);
1022		musb_writew(mbase, MUSB_INTRRXE, musb->intrrxe);
1023
1024		/* REVISIT if can_bulk_combine() use by updating "tmp"
1025		 * likewise high bandwidth periodic rx
1026		 */
1027		/* Set RXMAXP with the FIFO size of the endpoint
1028		 * to disable double buffering mode.
1029		 */
1030		musb_writew(regs, MUSB_RXMAXP, musb_ep->packet_sz
1031				| (musb_ep->hb_mult << 11));
1032
1033		/* force shared fifo to OUT-only mode */
1034		if (hw_ep->is_shared_fifo) {
1035			csr = musb_readw(regs, MUSB_TXCSR);
1036			csr &= ~(MUSB_TXCSR_MODE | MUSB_TXCSR_TXPKTRDY);
1037			musb_writew(regs, MUSB_TXCSR, csr);
1038		}
1039
1040		csr = MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_CLRDATATOG;
1041		if (musb_ep->type == USB_ENDPOINT_XFER_ISOC)
1042			csr |= MUSB_RXCSR_P_ISO;
1043		else if (musb_ep->type == USB_ENDPOINT_XFER_INT)
1044			csr |= MUSB_RXCSR_DISNYET;
1045
1046		/* set twice in case of double buffering */
1047		musb_writew(regs, MUSB_RXCSR, csr);
1048		musb_writew(regs, MUSB_RXCSR, csr);
1049	}
1050
1051	/* NOTE:  all the I/O code _should_ work fine without DMA, in case
1052	 * for some reason you run out of channels here.
1053	 */
1054	if (is_dma_capable() && musb->dma_controller) {
1055		struct dma_controller	*c = musb->dma_controller;
1056
1057		musb_ep->dma = c->channel_alloc(c, hw_ep,
1058				(desc->bEndpointAddress & USB_DIR_IN));
1059	} else
1060		musb_ep->dma = NULL;
1061
1062	musb_ep->desc = desc;
1063	musb_ep->busy = 0;
1064	musb_ep->wedged = 0;
1065	status = 0;
1066
1067	pr_debug("%s periph: enabled %s for %s %s, %smaxpacket %d\n",
1068			musb_driver_name, musb_ep->end_point.name,
1069			musb_ep_xfertype_string(musb_ep->type),
1070			musb_ep->is_in ? "IN" : "OUT",
1071			musb_ep->dma ? "dma, " : "",
1072			musb_ep->packet_sz);
1073
1074	schedule_delayed_work(&musb->irq_work, 0);
1075
1076fail:
1077	spin_unlock_irqrestore(&musb->lock, flags);
1078	return status;
1079}
1080
1081/*
1082 * Disable an endpoint flushing all requests queued.
1083 */
1084static int musb_gadget_disable(struct usb_ep *ep)
1085{
1086	unsigned long	flags;
1087	struct musb	*musb;
1088	u8		epnum;
1089	struct musb_ep	*musb_ep;
1090	void __iomem	*epio;
1091
1092	musb_ep = to_musb_ep(ep);
1093	musb = musb_ep->musb;
1094	epnum = musb_ep->current_epnum;
1095	epio = musb->endpoints[epnum].regs;
1096
1097	spin_lock_irqsave(&musb->lock, flags);
1098	musb_ep_select(musb->mregs, epnum);
1099
1100	/* zero the endpoint sizes */
1101	if (musb_ep->is_in) {
1102		musb->intrtxe &= ~(1 << epnum);
1103		musb_writew(musb->mregs, MUSB_INTRTXE, musb->intrtxe);
1104		musb_writew(epio, MUSB_TXMAXP, 0);
1105	} else {
1106		musb->intrrxe &= ~(1 << epnum);
1107		musb_writew(musb->mregs, MUSB_INTRRXE, musb->intrrxe);
1108		musb_writew(epio, MUSB_RXMAXP, 0);
1109	}
1110
1111	/* abort all pending DMA and requests */
1112	nuke(musb_ep, -ESHUTDOWN);
1113
1114	musb_ep->desc = NULL;
1115	musb_ep->end_point.desc = NULL;
1116
1117	schedule_delayed_work(&musb->irq_work, 0);
1118
1119	spin_unlock_irqrestore(&(musb->lock), flags);
1120
1121	musb_dbg(musb, "%s", musb_ep->end_point.name);
1122
1123	return 0;
1124}
1125
1126/*
1127 * Allocate a request for an endpoint.
1128 * Reused by ep0 code.
1129 */
1130struct usb_request *musb_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1131{
1132	struct musb_ep		*musb_ep = to_musb_ep(ep);
1133	struct musb_request	*request;
1134
1135	request = kzalloc(sizeof *request, gfp_flags);
1136	if (!request)
1137		return NULL;
1138
1139	request->request.dma = DMA_ADDR_INVALID;
1140	request->epnum = musb_ep->current_epnum;
1141	request->ep = musb_ep;
1142
1143	trace_musb_req_alloc(request);
1144	return &request->request;
1145}
1146
1147/*
1148 * Free a request
1149 * Reused by ep0 code.
1150 */
1151void musb_free_request(struct usb_ep *ep, struct usb_request *req)
1152{
1153	struct musb_request *request = to_musb_request(req);
1154
1155	trace_musb_req_free(request);
1156	kfree(request);
1157}
1158
1159static LIST_HEAD(buffers);
1160
1161struct free_record {
1162	struct list_head	list;
1163	struct device		*dev;
1164	unsigned		bytes;
1165	dma_addr_t		dma;
1166};
1167
1168/*
1169 * Context: controller locked, IRQs blocked.
1170 */
1171void musb_ep_restart(struct musb *musb, struct musb_request *req)
1172{
1173	trace_musb_req_start(req);
1174	musb_ep_select(musb->mregs, req->epnum);
1175	if (req->tx)
1176		txstate(musb, req);
1177	else
1178		rxstate(musb, req);
1179}
1180
1181static int musb_ep_restart_resume_work(struct musb *musb, void *data)
1182{
1183	struct musb_request *req = data;
1184
1185	musb_ep_restart(musb, req);
1186
1187	return 0;
1188}
1189
1190static int musb_gadget_queue(struct usb_ep *ep, struct usb_request *req,
1191			gfp_t gfp_flags)
1192{
1193	struct musb_ep		*musb_ep;
1194	struct musb_request	*request;
1195	struct musb		*musb;
1196	int			status;
1197	unsigned long		lockflags;
1198
1199	if (!ep || !req)
1200		return -EINVAL;
1201	if (!req->buf)
1202		return -ENODATA;
1203
1204	musb_ep = to_musb_ep(ep);
1205	musb = musb_ep->musb;
1206
1207	request = to_musb_request(req);
1208	request->musb = musb;
1209
1210	if (request->ep != musb_ep)
1211		return -EINVAL;
1212
1213	status = pm_runtime_get(musb->controller);
1214	if ((status != -EINPROGRESS) && status < 0) {
1215		dev_err(musb->controller,
1216			"pm runtime get failed in %s\n",
1217			__func__);
1218		pm_runtime_put_noidle(musb->controller);
1219
1220		return status;
1221	}
1222	status = 0;
1223
1224	trace_musb_req_enq(request);
1225
1226	/* request is mine now... */
1227	request->request.actual = 0;
1228	request->request.status = -EINPROGRESS;
1229	request->epnum = musb_ep->current_epnum;
1230	request->tx = musb_ep->is_in;
1231
1232	map_dma_buffer(request, musb, musb_ep);
1233
1234	spin_lock_irqsave(&musb->lock, lockflags);
1235
1236	/* don't queue if the ep is down */
1237	if (!musb_ep->desc) {
1238		musb_dbg(musb, "req %p queued to %s while ep %s",
1239				req, ep->name, "disabled");
1240		status = -ESHUTDOWN;
1241		unmap_dma_buffer(request, musb);
1242		goto unlock;
1243	}
1244
1245	/* add request to the list */
1246	list_add_tail(&request->list, &musb_ep->req_list);
1247
1248	/* it this is the head of the queue, start i/o ... */
1249	if (!musb_ep->busy && &request->list == musb_ep->req_list.next) {
1250		status = musb_queue_resume_work(musb,
1251						musb_ep_restart_resume_work,
1252						request);
1253		if (status < 0) {
1254			dev_err(musb->controller, "%s resume work: %i\n",
1255				__func__, status);
1256			list_del(&request->list);
1257		}
1258	}
1259
1260unlock:
1261	spin_unlock_irqrestore(&musb->lock, lockflags);
1262	pm_runtime_mark_last_busy(musb->controller);
1263	pm_runtime_put_autosuspend(musb->controller);
1264
1265	return status;
1266}
1267
1268static int musb_gadget_dequeue(struct usb_ep *ep, struct usb_request *request)
1269{
1270	struct musb_ep		*musb_ep = to_musb_ep(ep);
1271	struct musb_request	*req = to_musb_request(request);
1272	struct musb_request	*r;
1273	unsigned long		flags;
1274	int			status = 0;
1275	struct musb		*musb = musb_ep->musb;
1276
1277	if (!ep || !request || req->ep != musb_ep)
1278		return -EINVAL;
1279
1280	trace_musb_req_deq(req);
1281
1282	spin_lock_irqsave(&musb->lock, flags);
1283
1284	list_for_each_entry(r, &musb_ep->req_list, list) {
1285		if (r == req)
1286			break;
1287	}
1288	if (r != req) {
1289		dev_err(musb->controller, "request %p not queued to %s\n",
1290				request, ep->name);
1291		status = -EINVAL;
1292		goto done;
1293	}
1294
1295	/* if the hardware doesn't have the request, easy ... */
1296	if (musb_ep->req_list.next != &req->list || musb_ep->busy)
1297		musb_g_giveback(musb_ep, request, -ECONNRESET);
1298
1299	/* ... else abort the dma transfer ... */
1300	else if (is_dma_capable() && musb_ep->dma) {
1301		struct dma_controller	*c = musb->dma_controller;
1302
1303		musb_ep_select(musb->mregs, musb_ep->current_epnum);
1304		if (c->channel_abort)
1305			status = c->channel_abort(musb_ep->dma);
1306		else
1307			status = -EBUSY;
1308		if (status == 0)
1309			musb_g_giveback(musb_ep, request, -ECONNRESET);
1310	} else {
1311		/* NOTE: by sticking to easily tested hardware/driver states,
1312		 * we leave counting of in-flight packets imprecise.
1313		 */
1314		musb_g_giveback(musb_ep, request, -ECONNRESET);
1315	}
1316
1317done:
1318	spin_unlock_irqrestore(&musb->lock, flags);
1319	return status;
1320}
1321
1322/*
1323 * Set or clear the halt bit of an endpoint. A halted endpoint won't tx/rx any
1324 * data but will queue requests.
1325 *
1326 * exported to ep0 code
1327 */
1328static int musb_gadget_set_halt(struct usb_ep *ep, int value)
1329{
1330	struct musb_ep		*musb_ep = to_musb_ep(ep);
1331	u8			epnum = musb_ep->current_epnum;
1332	struct musb		*musb = musb_ep->musb;
1333	void __iomem		*epio = musb->endpoints[epnum].regs;
1334	void __iomem		*mbase;
1335	unsigned long		flags;
1336	u16			csr;
1337	struct musb_request	*request;
1338	int			status = 0;
1339
1340	if (!ep)
1341		return -EINVAL;
1342	mbase = musb->mregs;
1343
1344	spin_lock_irqsave(&musb->lock, flags);
1345
1346	if ((USB_ENDPOINT_XFER_ISOC == musb_ep->type)) {
1347		status = -EINVAL;
1348		goto done;
1349	}
1350
1351	musb_ep_select(mbase, epnum);
1352
1353	request = next_request(musb_ep);
1354	if (value) {
1355		if (request) {
1356			musb_dbg(musb, "request in progress, cannot halt %s",
1357			    ep->name);
1358			status = -EAGAIN;
1359			goto done;
1360		}
1361		/* Cannot portably stall with non-empty FIFO */
1362		if (musb_ep->is_in) {
1363			csr = musb_readw(epio, MUSB_TXCSR);
1364			if (csr & MUSB_TXCSR_FIFONOTEMPTY) {
1365				musb_dbg(musb, "FIFO busy, cannot halt %s",
1366						ep->name);
1367				status = -EAGAIN;
1368				goto done;
1369			}
1370		}
1371	} else
1372		musb_ep->wedged = 0;
1373
1374	/* set/clear the stall and toggle bits */
1375	musb_dbg(musb, "%s: %s stall", ep->name, value ? "set" : "clear");
1376	if (musb_ep->is_in) {
1377		csr = musb_readw(epio, MUSB_TXCSR);
1378		csr |= MUSB_TXCSR_P_WZC_BITS
1379			| MUSB_TXCSR_CLRDATATOG;
1380		if (value)
1381			csr |= MUSB_TXCSR_P_SENDSTALL;
1382		else
1383			csr &= ~(MUSB_TXCSR_P_SENDSTALL
1384				| MUSB_TXCSR_P_SENTSTALL);
1385		csr &= ~MUSB_TXCSR_TXPKTRDY;
1386		musb_writew(epio, MUSB_TXCSR, csr);
1387	} else {
1388		csr = musb_readw(epio, MUSB_RXCSR);
1389		csr |= MUSB_RXCSR_P_WZC_BITS
1390			| MUSB_RXCSR_FLUSHFIFO
1391			| MUSB_RXCSR_CLRDATATOG;
1392		if (value)
1393			csr |= MUSB_RXCSR_P_SENDSTALL;
1394		else
1395			csr &= ~(MUSB_RXCSR_P_SENDSTALL
1396				| MUSB_RXCSR_P_SENTSTALL);
1397		musb_writew(epio, MUSB_RXCSR, csr);
1398	}
1399
1400	/* maybe start the first request in the queue */
1401	if (!musb_ep->busy && !value && request) {
1402		musb_dbg(musb, "restarting the request");
1403		musb_ep_restart(musb, request);
1404	}
1405
1406done:
1407	spin_unlock_irqrestore(&musb->lock, flags);
1408	return status;
1409}
1410
1411/*
1412 * Sets the halt feature with the clear requests ignored
1413 */
1414static int musb_gadget_set_wedge(struct usb_ep *ep)
1415{
1416	struct musb_ep		*musb_ep = to_musb_ep(ep);
1417
1418	if (!ep)
1419		return -EINVAL;
1420
1421	musb_ep->wedged = 1;
1422
1423	return usb_ep_set_halt(ep);
1424}
1425
1426static int musb_gadget_fifo_status(struct usb_ep *ep)
1427{
1428	struct musb_ep		*musb_ep = to_musb_ep(ep);
1429	void __iomem		*epio = musb_ep->hw_ep->regs;
1430	int			retval = -EINVAL;
1431
1432	if (musb_ep->desc && !musb_ep->is_in) {
1433		struct musb		*musb = musb_ep->musb;
1434		int			epnum = musb_ep->current_epnum;
1435		void __iomem		*mbase = musb->mregs;
1436		unsigned long		flags;
1437
1438		spin_lock_irqsave(&musb->lock, flags);
1439
1440		musb_ep_select(mbase, epnum);
1441		/* FIXME return zero unless RXPKTRDY is set */
1442		retval = musb_readw(epio, MUSB_RXCOUNT);
1443
1444		spin_unlock_irqrestore(&musb->lock, flags);
1445	}
1446	return retval;
1447}
1448
1449static void musb_gadget_fifo_flush(struct usb_ep *ep)
1450{
1451	struct musb_ep	*musb_ep = to_musb_ep(ep);
1452	struct musb	*musb = musb_ep->musb;
1453	u8		epnum = musb_ep->current_epnum;
1454	void __iomem	*epio = musb->endpoints[epnum].regs;
1455	void __iomem	*mbase;
1456	unsigned long	flags;
1457	u16		csr;
1458
1459	mbase = musb->mregs;
1460
1461	spin_lock_irqsave(&musb->lock, flags);
1462	musb_ep_select(mbase, (u8) epnum);
1463
1464	/* disable interrupts */
1465	musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe & ~(1 << epnum));
1466
1467	if (musb_ep->is_in) {
1468		csr = musb_readw(epio, MUSB_TXCSR);
1469		if (csr & MUSB_TXCSR_FIFONOTEMPTY) {
1470			csr |= MUSB_TXCSR_FLUSHFIFO | MUSB_TXCSR_P_WZC_BITS;
1471			/*
1472			 * Setting both TXPKTRDY and FLUSHFIFO makes controller
1473			 * to interrupt current FIFO loading, but not flushing
1474			 * the already loaded ones.
1475			 */
1476			csr &= ~MUSB_TXCSR_TXPKTRDY;
1477			musb_writew(epio, MUSB_TXCSR, csr);
1478			/* REVISIT may be inappropriate w/o FIFONOTEMPTY ... */
1479			musb_writew(epio, MUSB_TXCSR, csr);
1480		}
1481	} else {
1482		csr = musb_readw(epio, MUSB_RXCSR);
1483		csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_P_WZC_BITS;
1484		musb_writew(epio, MUSB_RXCSR, csr);
1485		musb_writew(epio, MUSB_RXCSR, csr);
1486	}
1487
1488	/* re-enable interrupt */
1489	musb_writew(mbase, MUSB_INTRTXE, musb->intrtxe);
1490	spin_unlock_irqrestore(&musb->lock, flags);
1491}
1492
1493static const struct usb_ep_ops musb_ep_ops = {
1494	.enable		= musb_gadget_enable,
1495	.disable	= musb_gadget_disable,
1496	.alloc_request	= musb_alloc_request,
1497	.free_request	= musb_free_request,
1498	.queue		= musb_gadget_queue,
1499	.dequeue	= musb_gadget_dequeue,
1500	.set_halt	= musb_gadget_set_halt,
1501	.set_wedge	= musb_gadget_set_wedge,
1502	.fifo_status	= musb_gadget_fifo_status,
1503	.fifo_flush	= musb_gadget_fifo_flush
1504};
1505
1506/* ----------------------------------------------------------------------- */
1507
1508static int musb_gadget_get_frame(struct usb_gadget *gadget)
1509{
1510	struct musb	*musb = gadget_to_musb(gadget);
1511
1512	return (int)musb_readw(musb->mregs, MUSB_FRAME);
1513}
1514
1515static int musb_gadget_wakeup(struct usb_gadget *gadget)
1516{
1517	struct musb	*musb = gadget_to_musb(gadget);
1518	void __iomem	*mregs = musb->mregs;
1519	unsigned long	flags;
1520	int		status = -EINVAL;
1521	u8		power, devctl;
1522	int		retries;
1523
1524	spin_lock_irqsave(&musb->lock, flags);
1525
1526	switch (musb_get_state(musb)) {
1527	case OTG_STATE_B_PERIPHERAL:
1528		/* NOTE:  OTG state machine doesn't include B_SUSPENDED;
1529		 * that's part of the standard usb 1.1 state machine, and
1530		 * doesn't affect OTG transitions.
1531		 */
1532		if (musb->may_wakeup && musb->is_suspended)
1533			break;
1534		goto done;
1535	case OTG_STATE_B_IDLE:
1536		/* Start SRP ... OTG not required. */
1537		devctl = musb_readb(mregs, MUSB_DEVCTL);
1538		musb_dbg(musb, "Sending SRP: devctl: %02x", devctl);
1539		devctl |= MUSB_DEVCTL_SESSION;
1540		musb_writeb(mregs, MUSB_DEVCTL, devctl);
1541		devctl = musb_readb(mregs, MUSB_DEVCTL);
1542		retries = 100;
1543		while (!(devctl & MUSB_DEVCTL_SESSION)) {
1544			devctl = musb_readb(mregs, MUSB_DEVCTL);
1545			if (retries-- < 1)
1546				break;
1547		}
1548		retries = 10000;
1549		while (devctl & MUSB_DEVCTL_SESSION) {
1550			devctl = musb_readb(mregs, MUSB_DEVCTL);
1551			if (retries-- < 1)
1552				break;
1553		}
1554
1555		if (musb->xceiv) {
1556			spin_unlock_irqrestore(&musb->lock, flags);
1557			otg_start_srp(musb->xceiv->otg);
1558			spin_lock_irqsave(&musb->lock, flags);
1559		}
1560
1561		/* Block idling for at least 1s */
1562		musb_platform_try_idle(musb,
1563			jiffies + msecs_to_jiffies(1 * HZ));
1564
1565		status = 0;
1566		goto done;
1567	default:
1568		musb_dbg(musb, "Unhandled wake: %s",
1569			 musb_otg_state_string(musb));
1570		goto done;
1571	}
1572
1573	status = 0;
1574
1575	power = musb_readb(mregs, MUSB_POWER);
1576	power |= MUSB_POWER_RESUME;
1577	musb_writeb(mregs, MUSB_POWER, power);
1578	musb_dbg(musb, "issue wakeup");
1579
1580	/* FIXME do this next chunk in a timer callback, no udelay */
1581	mdelay(2);
1582
1583	power = musb_readb(mregs, MUSB_POWER);
1584	power &= ~MUSB_POWER_RESUME;
1585	musb_writeb(mregs, MUSB_POWER, power);
1586done:
1587	spin_unlock_irqrestore(&musb->lock, flags);
1588	return status;
1589}
1590
1591static int
1592musb_gadget_set_self_powered(struct usb_gadget *gadget, int is_selfpowered)
1593{
1594	gadget->is_selfpowered = !!is_selfpowered;
1595	return 0;
1596}
1597
1598static void musb_pullup(struct musb *musb, int is_on)
1599{
1600	u8 power;
1601
1602	power = musb_readb(musb->mregs, MUSB_POWER);
1603	if (is_on)
1604		power |= MUSB_POWER_SOFTCONN;
1605	else
1606		power &= ~MUSB_POWER_SOFTCONN;
1607
1608	/* FIXME if on, HdrcStart; if off, HdrcStop */
1609
1610	musb_dbg(musb, "gadget D+ pullup %s",
1611		is_on ? "on" : "off");
1612	musb_writeb(musb->mregs, MUSB_POWER, power);
1613}
1614
1615#if 0
1616static int musb_gadget_vbus_session(struct usb_gadget *gadget, int is_active)
1617{
1618	musb_dbg(musb, "<= %s =>\n", __func__);
1619
1620	/*
1621	 * FIXME iff driver's softconnect flag is set (as it is during probe,
1622	 * though that can clear it), just musb_pullup().
1623	 */
1624
1625	return -EINVAL;
1626}
1627#endif
1628
1629static int musb_gadget_vbus_draw(struct usb_gadget *gadget, unsigned mA)
1630{
1631	struct musb	*musb = gadget_to_musb(gadget);
1632
1633	return usb_phy_set_power(musb->xceiv, mA);
1634}
1635
1636static void musb_gadget_work(struct work_struct *work)
1637{
1638	struct musb *musb;
1639	unsigned long flags;
1640
1641	musb = container_of(work, struct musb, gadget_work.work);
1642	pm_runtime_get_sync(musb->controller);
1643	spin_lock_irqsave(&musb->lock, flags);
1644	musb_pullup(musb, musb->softconnect);
1645	spin_unlock_irqrestore(&musb->lock, flags);
1646	pm_runtime_mark_last_busy(musb->controller);
1647	pm_runtime_put_autosuspend(musb->controller);
1648}
1649
1650static int musb_gadget_pullup(struct usb_gadget *gadget, int is_on)
1651{
1652	struct musb	*musb = gadget_to_musb(gadget);
1653	unsigned long	flags;
1654
1655	is_on = !!is_on;
1656
1657	/* NOTE: this assumes we are sensing vbus; we'd rather
1658	 * not pullup unless the B-session is active.
1659	 */
1660	spin_lock_irqsave(&musb->lock, flags);
1661	if (is_on != musb->softconnect) {
1662		musb->softconnect = is_on;
1663		schedule_delayed_work(&musb->gadget_work, 0);
1664	}
1665	spin_unlock_irqrestore(&musb->lock, flags);
1666
1667	return 0;
1668}
1669
1670static int musb_gadget_start(struct usb_gadget *g,
1671		struct usb_gadget_driver *driver);
1672static int musb_gadget_stop(struct usb_gadget *g);
1673
1674static const struct usb_gadget_ops musb_gadget_operations = {
1675	.get_frame		= musb_gadget_get_frame,
1676	.wakeup			= musb_gadget_wakeup,
1677	.set_selfpowered	= musb_gadget_set_self_powered,
1678	/* .vbus_session		= musb_gadget_vbus_session, */
1679	.vbus_draw		= musb_gadget_vbus_draw,
1680	.pullup			= musb_gadget_pullup,
1681	.udc_start		= musb_gadget_start,
1682	.udc_stop		= musb_gadget_stop,
1683};
1684
1685/* ----------------------------------------------------------------------- */
1686
1687/* Registration */
1688
1689/* Only this registration code "knows" the rule (from USB standards)
1690 * about there being only one external upstream port.  It assumes
1691 * all peripheral ports are external...
1692 */
1693
1694static void
1695init_peripheral_ep(struct musb *musb, struct musb_ep *ep, u8 epnum, int is_in)
1696{
1697	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1698
1699	memset(ep, 0, sizeof *ep);
1700
1701	ep->current_epnum = epnum;
1702	ep->musb = musb;
1703	ep->hw_ep = hw_ep;
1704	ep->is_in = is_in;
1705
1706	INIT_LIST_HEAD(&ep->req_list);
1707
1708	sprintf(ep->name, "ep%d%s", epnum,
1709			(!epnum || hw_ep->is_shared_fifo) ? "" : (
1710				is_in ? "in" : "out"));
1711	ep->end_point.name = ep->name;
1712	INIT_LIST_HEAD(&ep->end_point.ep_list);
1713	if (!epnum) {
1714		usb_ep_set_maxpacket_limit(&ep->end_point, 64);
1715		ep->end_point.caps.type_control = true;
1716		ep->end_point.ops = &musb_g_ep0_ops;
1717		musb->g.ep0 = &ep->end_point;
1718	} else {
1719		if (is_in)
1720			usb_ep_set_maxpacket_limit(&ep->end_point, hw_ep->max_packet_sz_tx);
1721		else
1722			usb_ep_set_maxpacket_limit(&ep->end_point, hw_ep->max_packet_sz_rx);
1723		ep->end_point.caps.type_iso = true;
1724		ep->end_point.caps.type_bulk = true;
1725		ep->end_point.caps.type_int = true;
1726		ep->end_point.ops = &musb_ep_ops;
1727		list_add_tail(&ep->end_point.ep_list, &musb->g.ep_list);
1728	}
1729
1730	if (!epnum || hw_ep->is_shared_fifo) {
1731		ep->end_point.caps.dir_in = true;
1732		ep->end_point.caps.dir_out = true;
1733	} else if (is_in)
1734		ep->end_point.caps.dir_in = true;
1735	else
1736		ep->end_point.caps.dir_out = true;
1737}
1738
1739/*
1740 * Initialize the endpoints exposed to peripheral drivers, with backlinks
1741 * to the rest of the driver state.
1742 */
1743static inline void musb_g_init_endpoints(struct musb *musb)
1744{
1745	u8			epnum;
1746	struct musb_hw_ep	*hw_ep;
1747	unsigned		count = 0;
1748
1749	/* initialize endpoint list just once */
1750	INIT_LIST_HEAD(&(musb->g.ep_list));
1751
1752	for (epnum = 0, hw_ep = musb->endpoints;
1753			epnum < musb->nr_endpoints;
1754			epnum++, hw_ep++) {
1755		if (hw_ep->is_shared_fifo /* || !epnum */) {
1756			init_peripheral_ep(musb, &hw_ep->ep_in, epnum, 0);
1757			count++;
1758		} else {
1759			if (hw_ep->max_packet_sz_tx) {
1760				init_peripheral_ep(musb, &hw_ep->ep_in,
1761							epnum, 1);
1762				count++;
1763			}
1764			if (hw_ep->max_packet_sz_rx) {
1765				init_peripheral_ep(musb, &hw_ep->ep_out,
1766							epnum, 0);
1767				count++;
1768			}
1769		}
1770	}
1771}
1772
1773/* called once during driver setup to initialize and link into
1774 * the driver model; memory is zeroed.
1775 */
1776int musb_gadget_setup(struct musb *musb)
1777{
1778	int status;
1779
1780	/* REVISIT minor race:  if (erroneously) setting up two
1781	 * musb peripherals at the same time, only the bus lock
1782	 * is probably held.
1783	 */
1784
1785	musb->g.ops = &musb_gadget_operations;
1786	musb->g.max_speed = USB_SPEED_HIGH;
1787	musb->g.speed = USB_SPEED_UNKNOWN;
1788
1789	MUSB_DEV_MODE(musb);
1790	musb_set_state(musb, OTG_STATE_B_IDLE);
1791
1792	/* this "gadget" abstracts/virtualizes the controller */
1793	musb->g.name = musb_driver_name;
1794	/* don't support otg protocols */
1795	musb->g.is_otg = 0;
1796	INIT_DELAYED_WORK(&musb->gadget_work, musb_gadget_work);
1797	musb_g_init_endpoints(musb);
1798
1799	musb->is_active = 0;
1800	musb_platform_try_idle(musb, 0);
1801
1802	status = usb_add_gadget_udc(musb->controller, &musb->g);
1803	if (status)
1804		goto err;
1805
1806	return 0;
1807err:
1808	musb->g.dev.parent = NULL;
1809	device_unregister(&musb->g.dev);
1810	return status;
1811}
1812
1813void musb_gadget_cleanup(struct musb *musb)
1814{
1815	if (musb->port_mode == MUSB_HOST)
1816		return;
1817
1818	cancel_delayed_work_sync(&musb->gadget_work);
1819	usb_del_gadget_udc(&musb->g);
1820}
1821
1822/*
1823 * Register the gadget driver. Used by gadget drivers when
1824 * registering themselves with the controller.
1825 *
1826 * -EINVAL something went wrong (not driver)
1827 * -EBUSY another gadget is already using the controller
1828 * -ENOMEM no memory to perform the operation
1829 *
1830 * @param driver the gadget driver
1831 * @return <0 if error, 0 if everything is fine
1832 */
1833static int musb_gadget_start(struct usb_gadget *g,
1834		struct usb_gadget_driver *driver)
1835{
1836	struct musb		*musb = gadget_to_musb(g);
1837	unsigned long		flags;
1838	int			retval = 0;
1839
1840	if (driver->max_speed < USB_SPEED_HIGH) {
1841		retval = -EINVAL;
1842		goto err;
1843	}
1844
1845	pm_runtime_get_sync(musb->controller);
1846
1847	musb->softconnect = 0;
1848	musb->gadget_driver = driver;
1849
1850	spin_lock_irqsave(&musb->lock, flags);
1851	musb->is_active = 1;
1852
1853	if (musb->xceiv)
1854		otg_set_peripheral(musb->xceiv->otg, &musb->g);
1855	else
1856		phy_set_mode(musb->phy, PHY_MODE_USB_DEVICE);
1857
1858	musb_set_state(musb, OTG_STATE_B_IDLE);
1859	spin_unlock_irqrestore(&musb->lock, flags);
1860
1861	musb_start(musb);
1862
1863	/* REVISIT:  funcall to other code, which also
1864	 * handles power budgeting ... this way also
1865	 * ensures HdrcStart is indirectly called.
1866	 */
1867	if (musb->xceiv && musb->xceiv->last_event == USB_EVENT_ID)
1868		musb_platform_set_vbus(musb, 1);
1869
1870	pm_runtime_mark_last_busy(musb->controller);
1871	pm_runtime_put_autosuspend(musb->controller);
1872
1873	return 0;
1874
1875err:
1876	return retval;
1877}
1878
1879/*
1880 * Unregister the gadget driver. Used by gadget drivers when
1881 * unregistering themselves from the controller.
1882 *
1883 * @param driver the gadget driver to unregister
1884 */
1885static int musb_gadget_stop(struct usb_gadget *g)
1886{
1887	struct musb	*musb = gadget_to_musb(g);
1888	unsigned long	flags;
1889
1890	pm_runtime_get_sync(musb->controller);
1891
1892	/*
1893	 * REVISIT always use otg_set_peripheral() here too;
1894	 * this needs to shut down the OTG engine.
1895	 */
1896
1897	spin_lock_irqsave(&musb->lock, flags);
1898
1899	musb_hnp_stop(musb);
1900
1901	(void) musb_gadget_vbus_draw(&musb->g, 0);
1902
1903	musb_set_state(musb, OTG_STATE_UNDEFINED);
1904	musb_stop(musb);
1905
1906	if (musb->xceiv)
1907		otg_set_peripheral(musb->xceiv->otg, NULL);
1908	else
1909		phy_set_mode(musb->phy, PHY_MODE_INVALID);
1910
1911	musb->is_active = 0;
1912	musb->gadget_driver = NULL;
1913	musb_platform_try_idle(musb, 0);
1914	spin_unlock_irqrestore(&musb->lock, flags);
1915
1916	/*
1917	 * FIXME we need to be able to register another
1918	 * gadget driver here and have everything work;
1919	 * that currently misbehaves.
1920	 */
1921
1922	/* Force check of devctl register for PM runtime */
1923	pm_runtime_mark_last_busy(musb->controller);
1924	pm_runtime_put_autosuspend(musb->controller);
1925
1926	return 0;
1927}
1928
1929/* ----------------------------------------------------------------------- */
1930
1931/* lifecycle operations called through plat_uds.c */
1932
1933void musb_g_resume(struct musb *musb)
1934{
1935	musb->is_suspended = 0;
1936	switch (musb_get_state(musb)) {
1937	case OTG_STATE_B_IDLE:
1938		break;
1939	case OTG_STATE_B_WAIT_ACON:
1940	case OTG_STATE_B_PERIPHERAL:
1941		musb->is_active = 1;
1942		if (musb->gadget_driver && musb->gadget_driver->resume) {
1943			spin_unlock(&musb->lock);
1944			musb->gadget_driver->resume(&musb->g);
1945			spin_lock(&musb->lock);
1946		}
1947		break;
1948	default:
1949		WARNING("unhandled RESUME transition (%s)\n",
1950			musb_otg_state_string(musb));
1951	}
1952}
1953
1954/* called when SOF packets stop for 3+ msec */
1955void musb_g_suspend(struct musb *musb)
1956{
1957	u8	devctl;
1958
1959	devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
1960	musb_dbg(musb, "musb_g_suspend: devctl %02x", devctl);
1961
1962	switch (musb_get_state(musb)) {
1963	case OTG_STATE_B_IDLE:
1964		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
1965			musb_set_state(musb, OTG_STATE_B_PERIPHERAL);
1966		break;
1967	case OTG_STATE_B_PERIPHERAL:
1968		musb->is_suspended = 1;
1969		if (musb->gadget_driver && musb->gadget_driver->suspend) {
1970			spin_unlock(&musb->lock);
1971			musb->gadget_driver->suspend(&musb->g);
1972			spin_lock(&musb->lock);
1973		}
1974		break;
1975	default:
1976		/* REVISIT if B_HOST, clear DEVCTL.HOSTREQ;
1977		 * A_PERIPHERAL may need care too
1978		 */
1979		WARNING("unhandled SUSPEND transition (%s)",
1980			musb_otg_state_string(musb));
1981	}
1982}
1983
1984/* Called during SRP */
1985void musb_g_wakeup(struct musb *musb)
1986{
1987	musb_gadget_wakeup(&musb->g);
1988}
1989
1990/* called when VBUS drops below session threshold, and in other cases */
1991void musb_g_disconnect(struct musb *musb)
1992{
1993	void __iomem	*mregs = musb->mregs;
1994	u8	devctl = musb_readb(mregs, MUSB_DEVCTL);
1995
1996	musb_dbg(musb, "musb_g_disconnect: devctl %02x", devctl);
1997
1998	/* clear HR */
1999	musb_writeb(mregs, MUSB_DEVCTL, devctl & MUSB_DEVCTL_SESSION);
2000
2001	/* don't draw vbus until new b-default session */
2002	(void) musb_gadget_vbus_draw(&musb->g, 0);
2003
2004	musb->g.speed = USB_SPEED_UNKNOWN;
2005	if (musb->gadget_driver && musb->gadget_driver->disconnect) {
2006		spin_unlock(&musb->lock);
2007		musb->gadget_driver->disconnect(&musb->g);
2008		spin_lock(&musb->lock);
2009	}
2010
2011	switch (musb_get_state(musb)) {
2012	default:
2013		musb_dbg(musb, "Unhandled disconnect %s, setting a_idle",
2014			 musb_otg_state_string(musb));
2015		musb_set_state(musb, OTG_STATE_A_IDLE);
2016		MUSB_HST_MODE(musb);
2017		break;
2018	case OTG_STATE_A_PERIPHERAL:
2019		musb_set_state(musb, OTG_STATE_A_WAIT_BCON);
2020		MUSB_HST_MODE(musb);
2021		break;
2022	case OTG_STATE_B_WAIT_ACON:
2023	case OTG_STATE_B_HOST:
2024	case OTG_STATE_B_PERIPHERAL:
2025	case OTG_STATE_B_IDLE:
2026		musb_set_state(musb, OTG_STATE_B_IDLE);
2027		break;
2028	case OTG_STATE_B_SRP_INIT:
2029		break;
2030	}
2031
2032	musb->is_active = 0;
2033}
2034
2035void musb_g_reset(struct musb *musb)
2036__releases(musb->lock)
2037__acquires(musb->lock)
2038{
2039	void __iomem	*mbase = musb->mregs;
2040	u8		devctl = musb_readb(mbase, MUSB_DEVCTL);
2041	u8		power;
2042
2043	musb_dbg(musb, "<== %s driver '%s'",
2044			(devctl & MUSB_DEVCTL_BDEVICE)
2045				? "B-Device" : "A-Device",
2046			musb->gadget_driver
2047				? musb->gadget_driver->driver.name
2048				: NULL
2049			);
2050
2051	/* report reset, if we didn't already (flushing EP state) */
2052	if (musb->gadget_driver && musb->g.speed != USB_SPEED_UNKNOWN) {
2053		spin_unlock(&musb->lock);
2054		usb_gadget_udc_reset(&musb->g, musb->gadget_driver);
2055		spin_lock(&musb->lock);
2056	}
2057
2058	/* clear HR */
2059	else if (devctl & MUSB_DEVCTL_HR)
2060		musb_writeb(mbase, MUSB_DEVCTL, MUSB_DEVCTL_SESSION);
2061
2062
2063	/* what speed did we negotiate? */
2064	power = musb_readb(mbase, MUSB_POWER);
2065	musb->g.speed = (power & MUSB_POWER_HSMODE)
2066			? USB_SPEED_HIGH : USB_SPEED_FULL;
2067
2068	/* start in USB_STATE_DEFAULT */
2069	musb->is_active = 1;
2070	musb->is_suspended = 0;
2071	MUSB_DEV_MODE(musb);
2072	musb->address = 0;
2073	musb->ep0_state = MUSB_EP0_STAGE_SETUP;
2074
2075	musb->may_wakeup = 0;
2076	musb->g.b_hnp_enable = 0;
2077	musb->g.a_alt_hnp_support = 0;
2078	musb->g.a_hnp_support = 0;
2079	musb->g.quirk_zlp_not_supp = 1;
2080
2081	/* Normal reset, as B-Device;
2082	 * or else after HNP, as A-Device
2083	 */
2084	if (!musb->g.is_otg) {
2085		/* USB device controllers that are not OTG compatible
2086		 * may not have DEVCTL register in silicon.
2087		 * In that case, do not rely on devctl for setting
2088		 * peripheral mode.
2089		 */
2090		musb_set_state(musb, OTG_STATE_B_PERIPHERAL);
2091		musb->g.is_a_peripheral = 0;
2092	} else if (devctl & MUSB_DEVCTL_BDEVICE) {
2093		musb_set_state(musb, OTG_STATE_B_PERIPHERAL);
2094		musb->g.is_a_peripheral = 0;
2095	} else {
2096		musb_set_state(musb, OTG_STATE_A_PERIPHERAL);
2097		musb->g.is_a_peripheral = 1;
2098	}
2099
2100	/* start with default limits on VBUS power draw */
2101	(void) musb_gadget_vbus_draw(&musb->g, 8);
2102}