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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * gadget.c - DesignWare USB3 DRD Controller Gadget Framework Link
   4 *
   5 * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
   6 *
   7 * Authors: Felipe Balbi <balbi@ti.com>,
   8 *	    Sebastian Andrzej Siewior <bigeasy@linutronix.de>
   9 */
  10
  11#include <linux/kernel.h>
  12#include <linux/delay.h>
  13#include <linux/slab.h>
  14#include <linux/spinlock.h>
  15#include <linux/platform_device.h>
  16#include <linux/pm_runtime.h>
  17#include <linux/interrupt.h>
  18#include <linux/io.h>
  19#include <linux/list.h>
  20#include <linux/dma-mapping.h>
  21
  22#include <linux/usb/ch9.h>
  23#include <linux/usb/gadget.h>
  24
  25#include "debug.h"
  26#include "core.h"
  27#include "gadget.h"
  28#include "io.h"
  29
  30/**
  31 * dwc3_gadget_set_test_mode - enables usb2 test modes
  32 * @dwc: pointer to our context structure
  33 * @mode: the mode to set (J, K SE0 NAK, Force Enable)
  34 *
  35 * Caller should take care of locking. This function will return 0 on
  36 * success or -EINVAL if wrong Test Selector is passed.
  37 */
  38int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode)
  39{
  40	u32		reg;
  41
  42	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
  43	reg &= ~DWC3_DCTL_TSTCTRL_MASK;
  44
  45	switch (mode) {
  46	case TEST_J:
  47	case TEST_K:
  48	case TEST_SE0_NAK:
  49	case TEST_PACKET:
  50	case TEST_FORCE_EN:
  51		reg |= mode << 1;
  52		break;
  53	default:
  54		return -EINVAL;
  55	}
  56
  57	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
  58
  59	return 0;
  60}
  61
  62/**
  63 * dwc3_gadget_get_link_state - gets current state of usb link
  64 * @dwc: pointer to our context structure
  65 *
  66 * Caller should take care of locking. This function will
  67 * return the link state on success (>= 0) or -ETIMEDOUT.
  68 */
  69int dwc3_gadget_get_link_state(struct dwc3 *dwc)
  70{
  71	u32		reg;
  72
  73	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
  74
  75	return DWC3_DSTS_USBLNKST(reg);
  76}
  77
  78/**
  79 * dwc3_gadget_set_link_state - sets usb link to a particular state
  80 * @dwc: pointer to our context structure
  81 * @state: the state to put link into
  82 *
  83 * Caller should take care of locking. This function will
  84 * return 0 on success or -ETIMEDOUT.
  85 */
  86int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
  87{
  88	int		retries = 10000;
  89	u32		reg;
  90
  91	/*
  92	 * Wait until device controller is ready. Only applies to 1.94a and
  93	 * later RTL.
  94	 */
  95	if (dwc->revision >= DWC3_REVISION_194A) {
  96		while (--retries) {
  97			reg = dwc3_readl(dwc->regs, DWC3_DSTS);
  98			if (reg & DWC3_DSTS_DCNRD)
  99				udelay(5);
 100			else
 101				break;
 102		}
 103
 104		if (retries <= 0)
 105			return -ETIMEDOUT;
 106	}
 107
 108	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
 109	reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
 110
 111	/* set requested state */
 112	reg |= DWC3_DCTL_ULSTCHNGREQ(state);
 113	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
 114
 115	/*
 116	 * The following code is racy when called from dwc3_gadget_wakeup,
 117	 * and is not needed, at least on newer versions
 118	 */
 119	if (dwc->revision >= DWC3_REVISION_194A)
 120		return 0;
 121
 122	/* wait for a change in DSTS */
 123	retries = 10000;
 124	while (--retries) {
 125		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
 126
 127		if (DWC3_DSTS_USBLNKST(reg) == state)
 128			return 0;
 129
 130		udelay(5);
 131	}
 132
 133	return -ETIMEDOUT;
 134}
 135
 136/**
 137 * dwc3_ep_inc_trb - increment a trb index.
 138 * @index: Pointer to the TRB index to increment.
 139 *
 140 * The index should never point to the link TRB. After incrementing,
 141 * if it is point to the link TRB, wrap around to the beginning. The
 142 * link TRB is always at the last TRB entry.
 143 */
 144static void dwc3_ep_inc_trb(u8 *index)
 145{
 146	(*index)++;
 147	if (*index == (DWC3_TRB_NUM - 1))
 148		*index = 0;
 149}
 150
 151/**
 152 * dwc3_ep_inc_enq - increment endpoint's enqueue pointer
 153 * @dep: The endpoint whose enqueue pointer we're incrementing
 154 */
 155static void dwc3_ep_inc_enq(struct dwc3_ep *dep)
 156{
 157	dwc3_ep_inc_trb(&dep->trb_enqueue);
 158}
 159
 160/**
 161 * dwc3_ep_inc_deq - increment endpoint's dequeue pointer
 162 * @dep: The endpoint whose enqueue pointer we're incrementing
 163 */
 164static void dwc3_ep_inc_deq(struct dwc3_ep *dep)
 165{
 166	dwc3_ep_inc_trb(&dep->trb_dequeue);
 167}
 168
 169static void dwc3_gadget_del_and_unmap_request(struct dwc3_ep *dep,
 170		struct dwc3_request *req, int status)
 171{
 172	struct dwc3			*dwc = dep->dwc;
 173
 174	req->started = false;
 175	list_del(&req->list);
 176	req->remaining = 0;
 177
 178	if (req->request.status == -EINPROGRESS)
 179		req->request.status = status;
 180
 181	if (req->trb)
 182		usb_gadget_unmap_request_by_dev(dwc->sysdev,
 183				&req->request, req->direction);
 184
 185	req->trb = NULL;
 186	trace_dwc3_gadget_giveback(req);
 187
 188	if (dep->number > 1)
 189		pm_runtime_put(dwc->dev);
 190}
 191
 192/**
 193 * dwc3_gadget_giveback - call struct usb_request's ->complete callback
 194 * @dep: The endpoint to whom the request belongs to
 195 * @req: The request we're giving back
 196 * @status: completion code for the request
 197 *
 198 * Must be called with controller's lock held and interrupts disabled. This
 199 * function will unmap @req and call its ->complete() callback to notify upper
 200 * layers that it has completed.
 201 */
 202void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
 203		int status)
 204{
 205	struct dwc3			*dwc = dep->dwc;
 206
 207	dwc3_gadget_del_and_unmap_request(dep, req, status);
 208
 209	spin_unlock(&dwc->lock);
 210	usb_gadget_giveback_request(&dep->endpoint, &req->request);
 211	spin_lock(&dwc->lock);
 212}
 213
 214/**
 215 * dwc3_send_gadget_generic_command - issue a generic command for the controller
 216 * @dwc: pointer to the controller context
 217 * @cmd: the command to be issued
 218 * @param: command parameter
 219 *
 220 * Caller should take care of locking. Issue @cmd with a given @param to @dwc
 221 * and wait for its completion.
 222 */
 223int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param)
 224{
 225	u32		timeout = 500;
 226	int		status = 0;
 227	int		ret = 0;
 228	u32		reg;
 229
 230	dwc3_writel(dwc->regs, DWC3_DGCMDPAR, param);
 231	dwc3_writel(dwc->regs, DWC3_DGCMD, cmd | DWC3_DGCMD_CMDACT);
 232
 233	do {
 234		reg = dwc3_readl(dwc->regs, DWC3_DGCMD);
 235		if (!(reg & DWC3_DGCMD_CMDACT)) {
 236			status = DWC3_DGCMD_STATUS(reg);
 237			if (status)
 238				ret = -EINVAL;
 239			break;
 240		}
 241	} while (--timeout);
 242
 243	if (!timeout) {
 244		ret = -ETIMEDOUT;
 245		status = -ETIMEDOUT;
 246	}
 247
 248	trace_dwc3_gadget_generic_cmd(cmd, param, status);
 249
 250	return ret;
 251}
 252
 253static int __dwc3_gadget_wakeup(struct dwc3 *dwc);
 254
 255/**
 256 * dwc3_send_gadget_ep_cmd - issue an endpoint command
 257 * @dep: the endpoint to which the command is going to be issued
 258 * @cmd: the command to be issued
 259 * @params: parameters to the command
 260 *
 261 * Caller should handle locking. This function will issue @cmd with given
 262 * @params to @dep and wait for its completion.
 263 */
 264int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned cmd,
 265		struct dwc3_gadget_ep_cmd_params *params)
 266{
 267	const struct usb_endpoint_descriptor *desc = dep->endpoint.desc;
 268	struct dwc3		*dwc = dep->dwc;
 269	u32			timeout = 1000;
 270	u32			reg;
 271
 272	int			cmd_status = 0;
 273	int			susphy = false;
 274	int			ret = -EINVAL;
 275
 276	/*
 277	 * Synopsys Databook 2.60a states, on section 6.3.2.5.[1-8], that if
 278	 * we're issuing an endpoint command, we must check if
 279	 * GUSB2PHYCFG.SUSPHY bit is set. If it is, then we need to clear it.
 280	 *
 281	 * We will also set SUSPHY bit to what it was before returning as stated
 282	 * by the same section on Synopsys databook.
 283	 */
 284	if (dwc->gadget.speed <= USB_SPEED_HIGH) {
 285		reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
 286		if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) {
 287			susphy = true;
 288			reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
 289			dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
 290		}
 291	}
 292
 293	if (DWC3_DEPCMD_CMD(cmd) == DWC3_DEPCMD_STARTTRANSFER) {
 294		int		needs_wakeup;
 295
 296		needs_wakeup = (dwc->link_state == DWC3_LINK_STATE_U1 ||
 297				dwc->link_state == DWC3_LINK_STATE_U2 ||
 298				dwc->link_state == DWC3_LINK_STATE_U3);
 299
 300		if (unlikely(needs_wakeup)) {
 301			ret = __dwc3_gadget_wakeup(dwc);
 302			dev_WARN_ONCE(dwc->dev, ret, "wakeup failed --> %d\n",
 303					ret);
 304		}
 305	}
 306
 307	dwc3_writel(dep->regs, DWC3_DEPCMDPAR0, params->param0);
 308	dwc3_writel(dep->regs, DWC3_DEPCMDPAR1, params->param1);
 309	dwc3_writel(dep->regs, DWC3_DEPCMDPAR2, params->param2);
 310
 311	/*
 312	 * Synopsys Databook 2.60a states in section 6.3.2.5.6 of that if we're
 313	 * not relying on XferNotReady, we can make use of a special "No
 314	 * Response Update Transfer" command where we should clear both CmdAct
 315	 * and CmdIOC bits.
 316	 *
 317	 * With this, we don't need to wait for command completion and can
 318	 * straight away issue further commands to the endpoint.
 319	 *
 320	 * NOTICE: We're making an assumption that control endpoints will never
 321	 * make use of Update Transfer command. This is a safe assumption
 322	 * because we can never have more than one request at a time with
 323	 * Control Endpoints. If anybody changes that assumption, this chunk
 324	 * needs to be updated accordingly.
 325	 */
 326	if (DWC3_DEPCMD_CMD(cmd) == DWC3_DEPCMD_UPDATETRANSFER &&
 327			!usb_endpoint_xfer_isoc(desc))
 328		cmd &= ~(DWC3_DEPCMD_CMDIOC | DWC3_DEPCMD_CMDACT);
 329	else
 330		cmd |= DWC3_DEPCMD_CMDACT;
 331
 332	dwc3_writel(dep->regs, DWC3_DEPCMD, cmd);
 333	do {
 334		reg = dwc3_readl(dep->regs, DWC3_DEPCMD);
 335		if (!(reg & DWC3_DEPCMD_CMDACT)) {
 336			cmd_status = DWC3_DEPCMD_STATUS(reg);
 337
 338			switch (cmd_status) {
 339			case 0:
 340				ret = 0;
 341				break;
 342			case DEPEVT_TRANSFER_NO_RESOURCE:
 343				ret = -EINVAL;
 344				break;
 345			case DEPEVT_TRANSFER_BUS_EXPIRY:
 346				/*
 347				 * SW issues START TRANSFER command to
 348				 * isochronous ep with future frame interval. If
 349				 * future interval time has already passed when
 350				 * core receives the command, it will respond
 351				 * with an error status of 'Bus Expiry'.
 352				 *
 353				 * Instead of always returning -EINVAL, let's
 354				 * give a hint to the gadget driver that this is
 355				 * the case by returning -EAGAIN.
 356				 */
 357				ret = -EAGAIN;
 358				break;
 359			default:
 360				dev_WARN(dwc->dev, "UNKNOWN cmd status\n");
 361			}
 362
 363			break;
 364		}
 365	} while (--timeout);
 366
 367	if (timeout == 0) {
 368		ret = -ETIMEDOUT;
 369		cmd_status = -ETIMEDOUT;
 370	}
 371
 372	trace_dwc3_gadget_ep_cmd(dep, cmd, params, cmd_status);
 373
 374	if (ret == 0) {
 375		switch (DWC3_DEPCMD_CMD(cmd)) {
 376		case DWC3_DEPCMD_STARTTRANSFER:
 377			dep->flags |= DWC3_EP_TRANSFER_STARTED;
 378			break;
 379		case DWC3_DEPCMD_ENDTRANSFER:
 380			dep->flags &= ~DWC3_EP_TRANSFER_STARTED;
 381			break;
 382		default:
 383			/* nothing */
 384			break;
 385		}
 386	}
 387
 388	if (unlikely(susphy)) {
 389		reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
 390		reg |= DWC3_GUSB2PHYCFG_SUSPHY;
 391		dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
 392	}
 393
 394	return ret;
 395}
 396
 397static int dwc3_send_clear_stall_ep_cmd(struct dwc3_ep *dep)
 398{
 399	struct dwc3 *dwc = dep->dwc;
 400	struct dwc3_gadget_ep_cmd_params params;
 401	u32 cmd = DWC3_DEPCMD_CLEARSTALL;
 402
 403	/*
 404	 * As of core revision 2.60a the recommended programming model
 405	 * is to set the ClearPendIN bit when issuing a Clear Stall EP
 406	 * command for IN endpoints. This is to prevent an issue where
 407	 * some (non-compliant) hosts may not send ACK TPs for pending
 408	 * IN transfers due to a mishandled error condition. Synopsys
 409	 * STAR 9000614252.
 410	 */
 411	if (dep->direction && (dwc->revision >= DWC3_REVISION_260A) &&
 412	    (dwc->gadget.speed >= USB_SPEED_SUPER))
 413		cmd |= DWC3_DEPCMD_CLEARPENDIN;
 414
 415	memset(&params, 0, sizeof(params));
 416
 417	return dwc3_send_gadget_ep_cmd(dep, cmd, &params);
 418}
 419
 420static dma_addr_t dwc3_trb_dma_offset(struct dwc3_ep *dep,
 421		struct dwc3_trb *trb)
 422{
 423	u32		offset = (char *) trb - (char *) dep->trb_pool;
 424
 425	return dep->trb_pool_dma + offset;
 426}
 427
 428static int dwc3_alloc_trb_pool(struct dwc3_ep *dep)
 429{
 430	struct dwc3		*dwc = dep->dwc;
 431
 432	if (dep->trb_pool)
 433		return 0;
 434
 435	dep->trb_pool = dma_alloc_coherent(dwc->sysdev,
 436			sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
 437			&dep->trb_pool_dma, GFP_KERNEL);
 438	if (!dep->trb_pool) {
 439		dev_err(dep->dwc->dev, "failed to allocate trb pool for %s\n",
 440				dep->name);
 441		return -ENOMEM;
 442	}
 443
 444	return 0;
 445}
 446
 447static void dwc3_free_trb_pool(struct dwc3_ep *dep)
 448{
 449	struct dwc3		*dwc = dep->dwc;
 450
 451	dma_free_coherent(dwc->sysdev, sizeof(struct dwc3_trb) * DWC3_TRB_NUM,
 452			dep->trb_pool, dep->trb_pool_dma);
 453
 454	dep->trb_pool = NULL;
 455	dep->trb_pool_dma = 0;
 456}
 457
 458static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep);
 459
 460/**
 461 * dwc3_gadget_start_config - configure ep resources
 462 * @dwc: pointer to our controller context structure
 463 * @dep: endpoint that is being enabled
 464 *
 465 * Issue a %DWC3_DEPCMD_DEPSTARTCFG command to @dep. After the command's
 466 * completion, it will set Transfer Resource for all available endpoints.
 467 *
 468 * The assignment of transfer resources cannot perfectly follow the data book
 469 * due to the fact that the controller driver does not have all knowledge of the
 470 * configuration in advance. It is given this information piecemeal by the
 471 * composite gadget framework after every SET_CONFIGURATION and
 472 * SET_INTERFACE. Trying to follow the databook programming model in this
 473 * scenario can cause errors. For two reasons:
 474 *
 475 * 1) The databook says to do %DWC3_DEPCMD_DEPSTARTCFG for every
 476 * %USB_REQ_SET_CONFIGURATION and %USB_REQ_SET_INTERFACE (8.1.5). This is
 477 * incorrect in the scenario of multiple interfaces.
 478 *
 479 * 2) The databook does not mention doing more %DWC3_DEPCMD_DEPXFERCFG for new
 480 * endpoint on alt setting (8.1.6).
 481 *
 482 * The following simplified method is used instead:
 483 *
 484 * All hardware endpoints can be assigned a transfer resource and this setting
 485 * will stay persistent until either a core reset or hibernation. So whenever we
 486 * do a %DWC3_DEPCMD_DEPSTARTCFG(0) we can go ahead and do
 487 * %DWC3_DEPCMD_DEPXFERCFG for every hardware endpoint as well. We are
 488 * guaranteed that there are as many transfer resources as endpoints.
 489 *
 490 * This function is called for each endpoint when it is being enabled but is
 491 * triggered only when called for EP0-out, which always happens first, and which
 492 * should only happen in one of the above conditions.
 493 */
 494static int dwc3_gadget_start_config(struct dwc3 *dwc, struct dwc3_ep *dep)
 495{
 496	struct dwc3_gadget_ep_cmd_params params;
 497	u32			cmd;
 498	int			i;
 499	int			ret;
 500
 501	if (dep->number)
 502		return 0;
 503
 504	memset(&params, 0x00, sizeof(params));
 505	cmd = DWC3_DEPCMD_DEPSTARTCFG;
 506
 507	ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
 508	if (ret)
 509		return ret;
 510
 511	for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
 512		struct dwc3_ep *dep = dwc->eps[i];
 513
 514		if (!dep)
 515			continue;
 516
 517		ret = dwc3_gadget_set_xfer_resource(dwc, dep);
 518		if (ret)
 519			return ret;
 520	}
 521
 522	return 0;
 523}
 524
 525static int dwc3_gadget_set_ep_config(struct dwc3 *dwc, struct dwc3_ep *dep,
 526		bool modify, bool restore)
 527{
 528	const struct usb_ss_ep_comp_descriptor *comp_desc;
 529	const struct usb_endpoint_descriptor *desc;
 530	struct dwc3_gadget_ep_cmd_params params;
 531
 532	if (dev_WARN_ONCE(dwc->dev, modify && restore,
 533					"Can't modify and restore\n"))
 534		return -EINVAL;
 535
 536	comp_desc = dep->endpoint.comp_desc;
 537	desc = dep->endpoint.desc;
 538
 539	memset(&params, 0x00, sizeof(params));
 540
 541	params.param0 = DWC3_DEPCFG_EP_TYPE(usb_endpoint_type(desc))
 542		| DWC3_DEPCFG_MAX_PACKET_SIZE(usb_endpoint_maxp(desc));
 543
 544	/* Burst size is only needed in SuperSpeed mode */
 545	if (dwc->gadget.speed >= USB_SPEED_SUPER) {
 546		u32 burst = dep->endpoint.maxburst;
 547		params.param0 |= DWC3_DEPCFG_BURST_SIZE(burst - 1);
 548	}
 549
 550	if (modify) {
 551		params.param0 |= DWC3_DEPCFG_ACTION_MODIFY;
 552	} else if (restore) {
 553		params.param0 |= DWC3_DEPCFG_ACTION_RESTORE;
 554		params.param2 |= dep->saved_state;
 555	} else {
 556		params.param0 |= DWC3_DEPCFG_ACTION_INIT;
 557	}
 558
 559	if (usb_endpoint_xfer_control(desc))
 560		params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN;
 561
 562	if (dep->number <= 1 || usb_endpoint_xfer_isoc(desc))
 563		params.param1 |= DWC3_DEPCFG_XFER_NOT_READY_EN;
 564
 565	if (usb_ss_max_streams(comp_desc) && usb_endpoint_xfer_bulk(desc)) {
 566		params.param1 |= DWC3_DEPCFG_STREAM_CAPABLE
 567			| DWC3_DEPCFG_STREAM_EVENT_EN;
 568		dep->stream_capable = true;
 569	}
 570
 571	if (!usb_endpoint_xfer_control(desc))
 572		params.param1 |= DWC3_DEPCFG_XFER_IN_PROGRESS_EN;
 573
 574	/*
 575	 * We are doing 1:1 mapping for endpoints, meaning
 576	 * Physical Endpoints 2 maps to Logical Endpoint 2 and
 577	 * so on. We consider the direction bit as part of the physical
 578	 * endpoint number. So USB endpoint 0x81 is 0x03.
 579	 */
 580	params.param1 |= DWC3_DEPCFG_EP_NUMBER(dep->number);
 581
 582	/*
 583	 * We must use the lower 16 TX FIFOs even though
 584	 * HW might have more
 585	 */
 586	if (dep->direction)
 587		params.param0 |= DWC3_DEPCFG_FIFO_NUMBER(dep->number >> 1);
 588
 589	if (desc->bInterval) {
 590		params.param1 |= DWC3_DEPCFG_BINTERVAL_M1(desc->bInterval - 1);
 591		dep->interval = 1 << (desc->bInterval - 1);
 592	}
 593
 594	return dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETEPCONFIG, &params);
 595}
 596
 597static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep)
 598{
 599	struct dwc3_gadget_ep_cmd_params params;
 600
 601	memset(&params, 0x00, sizeof(params));
 602
 603	params.param0 = DWC3_DEPXFERCFG_NUM_XFER_RES(1);
 604
 605	return dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETTRANSFRESOURCE,
 606			&params);
 607}
 608
 609/**
 610 * __dwc3_gadget_ep_enable - initializes a hw endpoint
 611 * @dep: endpoint to be initialized
 612 * @modify: if true, modify existing endpoint configuration
 613 * @restore: if true, restore endpoint configuration from scratch buffer
 614 *
 615 * Caller should take care of locking. Execute all necessary commands to
 616 * initialize a HW endpoint so it can be used by a gadget driver.
 617 */
 618static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
 619		bool modify, bool restore)
 620{
 621	const struct usb_endpoint_descriptor *desc = dep->endpoint.desc;
 622	struct dwc3		*dwc = dep->dwc;
 623
 624	u32			reg;
 625	int			ret;
 626
 627	if (!(dep->flags & DWC3_EP_ENABLED)) {
 628		ret = dwc3_gadget_start_config(dwc, dep);
 629		if (ret)
 630			return ret;
 631	}
 632
 633	ret = dwc3_gadget_set_ep_config(dwc, dep, modify, restore);
 634	if (ret)
 635		return ret;
 636
 637	if (!(dep->flags & DWC3_EP_ENABLED)) {
 638		struct dwc3_trb	*trb_st_hw;
 639		struct dwc3_trb	*trb_link;
 640
 641		dep->type = usb_endpoint_type(desc);
 642		dep->flags |= DWC3_EP_ENABLED;
 643		dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;
 644
 645		reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
 646		reg |= DWC3_DALEPENA_EP(dep->number);
 647		dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
 648
 649		init_waitqueue_head(&dep->wait_end_transfer);
 650
 651		if (usb_endpoint_xfer_control(desc))
 652			goto out;
 653
 654		/* Initialize the TRB ring */
 655		dep->trb_dequeue = 0;
 656		dep->trb_enqueue = 0;
 657		memset(dep->trb_pool, 0,
 658		       sizeof(struct dwc3_trb) * DWC3_TRB_NUM);
 659
 660		/* Link TRB. The HWO bit is never reset */
 661		trb_st_hw = &dep->trb_pool[0];
 662
 663		trb_link = &dep->trb_pool[DWC3_TRB_NUM - 1];
 664		trb_link->bpl = lower_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
 665		trb_link->bph = upper_32_bits(dwc3_trb_dma_offset(dep, trb_st_hw));
 666		trb_link->ctrl |= DWC3_TRBCTL_LINK_TRB;
 667		trb_link->ctrl |= DWC3_TRB_CTRL_HWO;
 668	}
 669
 670	/*
 671	 * Issue StartTransfer here with no-op TRB so we can always rely on No
 672	 * Response Update Transfer command.
 673	 */
 674	if (usb_endpoint_xfer_bulk(desc)) {
 675		struct dwc3_gadget_ep_cmd_params params;
 676		struct dwc3_trb	*trb;
 677		dma_addr_t trb_dma;
 678		u32 cmd;
 679
 680		memset(&params, 0, sizeof(params));
 681		trb = &dep->trb_pool[0];
 682		trb_dma = dwc3_trb_dma_offset(dep, trb);
 683
 684		params.param0 = upper_32_bits(trb_dma);
 685		params.param1 = lower_32_bits(trb_dma);
 686
 687		cmd = DWC3_DEPCMD_STARTTRANSFER;
 688
 689		ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
 690		if (ret < 0)
 691			return ret;
 692
 693		dep->flags |= DWC3_EP_BUSY;
 694
 695		dep->resource_index = dwc3_gadget_ep_get_transfer_index(dep);
 696		WARN_ON_ONCE(!dep->resource_index);
 697	}
 698
 699
 700out:
 701	trace_dwc3_gadget_ep_enable(dep);
 702
 703	return 0;
 704}
 705
 706static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force);
 707static void dwc3_remove_requests(struct dwc3 *dwc, struct dwc3_ep *dep)
 708{
 709	struct dwc3_request		*req;
 710
 711	dwc3_stop_active_transfer(dwc, dep->number, true);
 712
 713	/* - giveback all requests to gadget driver */
 714	while (!list_empty(&dep->started_list)) {
 715		req = next_request(&dep->started_list);
 716
 717		dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
 718	}
 719
 720	while (!list_empty(&dep->pending_list)) {
 721		req = next_request(&dep->pending_list);
 722
 723		dwc3_gadget_giveback(dep, req, -ESHUTDOWN);
 724	}
 725}
 726
 727/**
 728 * __dwc3_gadget_ep_disable - disables a hw endpoint
 729 * @dep: the endpoint to disable
 730 *
 731 * This function undoes what __dwc3_gadget_ep_enable did and also removes
 732 * requests which are currently being processed by the hardware and those which
 733 * are not yet scheduled.
 734 *
 735 * Caller should take care of locking.
 736 */
 737static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)
 738{
 739	struct dwc3		*dwc = dep->dwc;
 740	u32			reg;
 741
 742	trace_dwc3_gadget_ep_disable(dep);
 743
 744	dwc3_remove_requests(dwc, dep);
 745
 746	/* make sure HW endpoint isn't stalled */
 747	if (dep->flags & DWC3_EP_STALL)
 748		__dwc3_gadget_ep_set_halt(dep, 0, false);
 749
 750	reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
 751	reg &= ~DWC3_DALEPENA_EP(dep->number);
 752	dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
 753
 754	dep->stream_capable = false;
 755	dep->type = 0;
 756	dep->flags &= DWC3_EP_END_TRANSFER_PENDING;
 757
 758	/* Clear out the ep descriptors for non-ep0 */
 759	if (dep->number > 1) {
 760		dep->endpoint.comp_desc = NULL;
 761		dep->endpoint.desc = NULL;
 762	}
 763
 764	return 0;
 765}
 766
 767/* -------------------------------------------------------------------------- */
 768
 769static int dwc3_gadget_ep0_enable(struct usb_ep *ep,
 770		const struct usb_endpoint_descriptor *desc)
 771{
 772	return -EINVAL;
 773}
 774
 775static int dwc3_gadget_ep0_disable(struct usb_ep *ep)
 776{
 777	return -EINVAL;
 778}
 779
 780/* -------------------------------------------------------------------------- */
 781
 782static int dwc3_gadget_ep_enable(struct usb_ep *ep,
 783		const struct usb_endpoint_descriptor *desc)
 784{
 785	struct dwc3_ep			*dep;
 786	struct dwc3			*dwc;
 787	unsigned long			flags;
 788	int				ret;
 789
 790	if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
 791		pr_debug("dwc3: invalid parameters\n");
 792		return -EINVAL;
 793	}
 794
 795	if (!desc->wMaxPacketSize) {
 796		pr_debug("dwc3: missing wMaxPacketSize\n");
 797		return -EINVAL;
 798	}
 799
 800	dep = to_dwc3_ep(ep);
 801	dwc = dep->dwc;
 802
 803	if (dev_WARN_ONCE(dwc->dev, dep->flags & DWC3_EP_ENABLED,
 804					"%s is already enabled\n",
 805					dep->name))
 806		return 0;
 807
 808	spin_lock_irqsave(&dwc->lock, flags);
 809	ret = __dwc3_gadget_ep_enable(dep, false, false);
 810	spin_unlock_irqrestore(&dwc->lock, flags);
 811
 812	return ret;
 813}
 814
 815static int dwc3_gadget_ep_disable(struct usb_ep *ep)
 816{
 817	struct dwc3_ep			*dep;
 818	struct dwc3			*dwc;
 819	unsigned long			flags;
 820	int				ret;
 821
 822	if (!ep) {
 823		pr_debug("dwc3: invalid parameters\n");
 824		return -EINVAL;
 825	}
 826
 827	dep = to_dwc3_ep(ep);
 828	dwc = dep->dwc;
 829
 830	if (dev_WARN_ONCE(dwc->dev, !(dep->flags & DWC3_EP_ENABLED),
 831					"%s is already disabled\n",
 832					dep->name))
 833		return 0;
 834
 835	spin_lock_irqsave(&dwc->lock, flags);
 836	ret = __dwc3_gadget_ep_disable(dep);
 837	spin_unlock_irqrestore(&dwc->lock, flags);
 838
 839	return ret;
 840}
 841
 842static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
 843	gfp_t gfp_flags)
 844{
 845	struct dwc3_request		*req;
 846	struct dwc3_ep			*dep = to_dwc3_ep(ep);
 847
 848	req = kzalloc(sizeof(*req), gfp_flags);
 849	if (!req)
 850		return NULL;
 851
 852	req->epnum	= dep->number;
 853	req->dep	= dep;
 854
 855	dep->allocated_requests++;
 856
 857	trace_dwc3_alloc_request(req);
 858
 859	return &req->request;
 860}
 861
 862static void dwc3_gadget_ep_free_request(struct usb_ep *ep,
 863		struct usb_request *request)
 864{
 865	struct dwc3_request		*req = to_dwc3_request(request);
 866	struct dwc3_ep			*dep = to_dwc3_ep(ep);
 867
 868	dep->allocated_requests--;
 869	trace_dwc3_free_request(req);
 870	kfree(req);
 871}
 872
 873static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep);
 874
 875static void __dwc3_prepare_one_trb(struct dwc3_ep *dep, struct dwc3_trb *trb,
 876		dma_addr_t dma, unsigned length, unsigned chain, unsigned node,
 877		unsigned stream_id, unsigned short_not_ok, unsigned no_interrupt)
 878{
 879	struct dwc3		*dwc = dep->dwc;
 880	struct usb_gadget	*gadget = &dwc->gadget;
 881	enum usb_device_speed	speed = gadget->speed;
 882
 883	dwc3_ep_inc_enq(dep);
 884
 885	trb->size = DWC3_TRB_SIZE_LENGTH(length);
 886	trb->bpl = lower_32_bits(dma);
 887	trb->bph = upper_32_bits(dma);
 888
 889	switch (usb_endpoint_type(dep->endpoint.desc)) {
 890	case USB_ENDPOINT_XFER_CONTROL:
 891		trb->ctrl = DWC3_TRBCTL_CONTROL_SETUP;
 892		break;
 893
 894	case USB_ENDPOINT_XFER_ISOC:
 895		if (!node) {
 896			trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;
 897
 898			/*
 899			 * USB Specification 2.0 Section 5.9.2 states that: "If
 900			 * there is only a single transaction in the microframe,
 901			 * only a DATA0 data packet PID is used.  If there are
 902			 * two transactions per microframe, DATA1 is used for
 903			 * the first transaction data packet and DATA0 is used
 904			 * for the second transaction data packet.  If there are
 905			 * three transactions per microframe, DATA2 is used for
 906			 * the first transaction data packet, DATA1 is used for
 907			 * the second, and DATA0 is used for the third."
 908			 *
 909			 * IOW, we should satisfy the following cases:
 910			 *
 911			 * 1) length <= maxpacket
 912			 *	- DATA0
 913			 *
 914			 * 2) maxpacket < length <= (2 * maxpacket)
 915			 *	- DATA1, DATA0
 916			 *
 917			 * 3) (2 * maxpacket) < length <= (3 * maxpacket)
 918			 *	- DATA2, DATA1, DATA0
 919			 */
 920			if (speed == USB_SPEED_HIGH) {
 921				struct usb_ep *ep = &dep->endpoint;
 922				unsigned int mult = 2;
 923				unsigned int maxp = usb_endpoint_maxp(ep->desc);
 924
 925				if (length <= (2 * maxp))
 926					mult--;
 927
 928				if (length <= maxp)
 929					mult--;
 930
 931				trb->size |= DWC3_TRB_SIZE_PCM1(mult);
 932			}
 933		} else {
 934			trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
 935		}
 936
 937		/* always enable Interrupt on Missed ISOC */
 938		trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
 939		break;
 940
 941	case USB_ENDPOINT_XFER_BULK:
 942	case USB_ENDPOINT_XFER_INT:
 943		trb->ctrl = DWC3_TRBCTL_NORMAL;
 944		break;
 945	default:
 946		/*
 947		 * This is only possible with faulty memory because we
 948		 * checked it already :)
 949		 */
 950		dev_WARN(dwc->dev, "Unknown endpoint type %d\n",
 951				usb_endpoint_type(dep->endpoint.desc));
 952	}
 953
 954	/* always enable Continue on Short Packet */
 955	if (usb_endpoint_dir_out(dep->endpoint.desc)) {
 956		trb->ctrl |= DWC3_TRB_CTRL_CSP;
 957
 958		if (short_not_ok)
 959			trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
 960	}
 961
 962	if ((!no_interrupt && !chain) ||
 963			(dwc3_calc_trbs_left(dep) == 0))
 964		trb->ctrl |= DWC3_TRB_CTRL_IOC;
 965
 966	if (chain)
 967		trb->ctrl |= DWC3_TRB_CTRL_CHN;
 968
 969	if (usb_endpoint_xfer_bulk(dep->endpoint.desc) && dep->stream_capable)
 970		trb->ctrl |= DWC3_TRB_CTRL_SID_SOFN(stream_id);
 971
 972	trb->ctrl |= DWC3_TRB_CTRL_HWO;
 973
 974	trace_dwc3_prepare_trb(dep, trb);
 975}
 976
 977/**
 978 * dwc3_prepare_one_trb - setup one TRB from one request
 979 * @dep: endpoint for which this request is prepared
 980 * @req: dwc3_request pointer
 981 * @chain: should this TRB be chained to the next?
 982 * @node: only for isochronous endpoints. First TRB needs different type.
 983 */
 984static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
 985		struct dwc3_request *req, unsigned chain, unsigned node)
 986{
 987	struct dwc3_trb		*trb;
 988	unsigned		length = req->request.length;
 989	unsigned		stream_id = req->request.stream_id;
 990	unsigned		short_not_ok = req->request.short_not_ok;
 991	unsigned		no_interrupt = req->request.no_interrupt;
 992	dma_addr_t		dma = req->request.dma;
 993
 994	trb = &dep->trb_pool[dep->trb_enqueue];
 995
 996	if (!req->trb) {
 997		dwc3_gadget_move_started_request(req);
 998		req->trb = trb;
 999		req->trb_dma = dwc3_trb_dma_offset(dep, trb);
1000		dep->queued_requests++;
1001	}
1002
1003	__dwc3_prepare_one_trb(dep, trb, dma, length, chain, node,
1004			stream_id, short_not_ok, no_interrupt);
1005}
1006
1007/**
1008 * dwc3_ep_prev_trb - returns the previous TRB in the ring
1009 * @dep: The endpoint with the TRB ring
1010 * @index: The index of the current TRB in the ring
1011 *
1012 * Returns the TRB prior to the one pointed to by the index. If the
1013 * index is 0, we will wrap backwards, skip the link TRB, and return
1014 * the one just before that.
1015 */
1016static struct dwc3_trb *dwc3_ep_prev_trb(struct dwc3_ep *dep, u8 index)
1017{
1018	u8 tmp = index;
1019
1020	if (!tmp)
1021		tmp = DWC3_TRB_NUM - 1;
1022
1023	return &dep->trb_pool[tmp - 1];
1024}
1025
1026static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
1027{
1028	struct dwc3_trb		*tmp;
1029	u8			trbs_left;
1030
1031	/*
1032	 * If enqueue & dequeue are equal than it is either full or empty.
1033	 *
1034	 * One way to know for sure is if the TRB right before us has HWO bit
1035	 * set or not. If it has, then we're definitely full and can't fit any
1036	 * more transfers in our ring.
1037	 */
1038	if (dep->trb_enqueue == dep->trb_dequeue) {
1039		tmp = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
1040		if (tmp->ctrl & DWC3_TRB_CTRL_HWO)
1041			return 0;
1042
1043		return DWC3_TRB_NUM - 1;
1044	}
1045
1046	trbs_left = dep->trb_dequeue - dep->trb_enqueue;
1047	trbs_left &= (DWC3_TRB_NUM - 1);
1048
1049	if (dep->trb_dequeue < dep->trb_enqueue)
1050		trbs_left--;
1051
1052	return trbs_left;
1053}
1054
1055static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
1056		struct dwc3_request *req)
1057{
1058	struct scatterlist *sg = req->sg;
1059	struct scatterlist *s;
1060	int		i;
1061
1062	for_each_sg(sg, s, req->num_pending_sgs, i) {
1063		unsigned int length = req->request.length;
1064		unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);
1065		unsigned int rem = length % maxp;
1066		unsigned chain = true;
1067
1068		if (sg_is_last(s))
1069			chain = false;
1070
1071		if (rem && usb_endpoint_dir_out(dep->endpoint.desc) && !chain) {
1072			struct dwc3	*dwc = dep->dwc;
1073			struct dwc3_trb	*trb;
1074
1075			req->unaligned = true;
1076
1077			/* prepare normal TRB */
1078			dwc3_prepare_one_trb(dep, req, true, i);
1079
1080			/* Now prepare one extra TRB to align transfer size */
1081			trb = &dep->trb_pool[dep->trb_enqueue];
1082			__dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr,
1083					maxp - rem, false, 0,
1084					req->request.stream_id,
1085					req->request.short_not_ok,
1086					req->request.no_interrupt);
1087		} else {
1088			dwc3_prepare_one_trb(dep, req, chain, i);
1089		}
1090
1091		if (!dwc3_calc_trbs_left(dep))
1092			break;
1093	}
1094}
1095
1096static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
1097		struct dwc3_request *req)
1098{
1099	unsigned int length = req->request.length;
1100	unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);
1101	unsigned int rem = length % maxp;
1102
1103	if (rem && usb_endpoint_dir_out(dep->endpoint.desc)) {
1104		struct dwc3	*dwc = dep->dwc;
1105		struct dwc3_trb	*trb;
1106
1107		req->unaligned = true;
1108
1109		/* prepare normal TRB */
1110		dwc3_prepare_one_trb(dep, req, true, 0);
1111
1112		/* Now prepare one extra TRB to align transfer size */
1113		trb = &dep->trb_pool[dep->trb_enqueue];
1114		__dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr, maxp - rem,
1115				false, 0, req->request.stream_id,
1116				req->request.short_not_ok,
1117				req->request.no_interrupt);
1118	} else if (req->request.zero && req->request.length &&
1119		   (IS_ALIGNED(req->request.length,dep->endpoint.maxpacket))) {
1120		struct dwc3	*dwc = dep->dwc;
1121		struct dwc3_trb	*trb;
1122
1123		req->zero = true;
1124
1125		/* prepare normal TRB */
1126		dwc3_prepare_one_trb(dep, req, true, 0);
1127
1128		/* Now prepare one extra TRB to handle ZLP */
1129		trb = &dep->trb_pool[dep->trb_enqueue];
1130		__dwc3_prepare_one_trb(dep, trb, dwc->bounce_addr, 0,
1131				false, 0, req->request.stream_id,
1132				req->request.short_not_ok,
1133				req->request.no_interrupt);
1134	} else {
1135		dwc3_prepare_one_trb(dep, req, false, 0);
1136	}
1137}
1138
1139/*
1140 * dwc3_prepare_trbs - setup TRBs from requests
1141 * @dep: endpoint for which requests are being prepared
1142 *
1143 * The function goes through the requests list and sets up TRBs for the
1144 * transfers. The function returns once there are no more TRBs available or
1145 * it runs out of requests.
1146 */
1147static void dwc3_prepare_trbs(struct dwc3_ep *dep)
1148{
1149	struct dwc3_request	*req, *n;
1150
1151	BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
1152
1153	/*
1154	 * We can get in a situation where there's a request in the started list
1155	 * but there weren't enough TRBs to fully kick it in the first time
1156	 * around, so it has been waiting for more TRBs to be freed up.
1157	 *
1158	 * In that case, we should check if we have a request with pending_sgs
1159	 * in the started list and prepare TRBs for that request first,
1160	 * otherwise we will prepare TRBs completely out of order and that will
1161	 * break things.
1162	 */
1163	list_for_each_entry(req, &dep->started_list, list) {
1164		if (req->num_pending_sgs > 0)
1165			dwc3_prepare_one_trb_sg(dep, req);
1166
1167		if (!dwc3_calc_trbs_left(dep))
1168			return;
1169	}
1170
1171	list_for_each_entry_safe(req, n, &dep->pending_list, list) {
1172		struct dwc3	*dwc = dep->dwc;
1173		int		ret;
1174
1175		ret = usb_gadget_map_request_by_dev(dwc->sysdev, &req->request,
1176						    dep->direction);
1177		if (ret)
1178			return;
1179
1180		req->sg			= req->request.sg;
1181		req->num_pending_sgs	= req->request.num_mapped_sgs;
1182
1183		if (req->num_pending_sgs > 0)
1184			dwc3_prepare_one_trb_sg(dep, req);
1185		else
1186			dwc3_prepare_one_trb_linear(dep, req);
1187
1188		if (!dwc3_calc_trbs_left(dep))
1189			return;
1190	}
1191}
1192
1193static int __dwc3_gadget_kick_transfer(struct dwc3_ep *dep)
1194{
1195	struct dwc3_gadget_ep_cmd_params params;
1196	struct dwc3_request		*req;
1197	int				starting;
1198	int				ret;
1199	u32				cmd;
1200
1201	if (!dwc3_calc_trbs_left(dep))
1202		return 0;
1203
1204	starting = !(dep->flags & DWC3_EP_BUSY);
1205
1206	dwc3_prepare_trbs(dep);
1207	req = next_request(&dep->started_list);
1208	if (!req) {
1209		dep->flags |= DWC3_EP_PENDING_REQUEST;
1210		return 0;
1211	}
1212
1213	memset(&params, 0, sizeof(params));
1214
1215	if (starting) {
1216		params.param0 = upper_32_bits(req->trb_dma);
1217		params.param1 = lower_32_bits(req->trb_dma);
1218		cmd = DWC3_DEPCMD_STARTTRANSFER;
1219
1220		if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
1221			cmd |= DWC3_DEPCMD_PARAM(dep->frame_number);
1222	} else {
1223		cmd = DWC3_DEPCMD_UPDATETRANSFER |
1224			DWC3_DEPCMD_PARAM(dep->resource_index);
1225	}
1226
1227	ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
1228	if (ret < 0) {
1229		/*
1230		 * FIXME we need to iterate over the list of requests
1231		 * here and stop, unmap, free and del each of the linked
1232		 * requests instead of what we do now.
1233		 */
1234		if (req->trb)
1235			memset(req->trb, 0, sizeof(struct dwc3_trb));
1236		dep->queued_requests--;
1237		dwc3_gadget_del_and_unmap_request(dep, req, ret);
1238		return ret;
1239	}
1240
1241	dep->flags |= DWC3_EP_BUSY;
1242
1243	if (starting) {
1244		dep->resource_index = dwc3_gadget_ep_get_transfer_index(dep);
1245		WARN_ON_ONCE(!dep->resource_index);
1246	}
1247
1248	return 0;
1249}
1250
1251static int __dwc3_gadget_get_frame(struct dwc3 *dwc)
1252{
1253	u32			reg;
1254
1255	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1256	return DWC3_DSTS_SOFFN(reg);
1257}
1258
1259static void __dwc3_gadget_start_isoc(struct dwc3 *dwc,
1260		struct dwc3_ep *dep, u32 cur_uf)
1261{
1262	if (list_empty(&dep->pending_list)) {
1263		dev_info(dwc->dev, "%s: ran out of requests\n",
1264				dep->name);
1265		dep->flags |= DWC3_EP_PENDING_REQUEST;
1266		return;
1267	}
1268
1269	/*
1270	 * Schedule the first trb for one interval in the future or at
1271	 * least 4 microframes.
1272	 */
1273	dep->frame_number = cur_uf + max_t(u32, 4, dep->interval);
1274	__dwc3_gadget_kick_transfer(dep);
1275}
1276
1277static void dwc3_gadget_start_isoc(struct dwc3 *dwc,
1278		struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
1279{
1280	u32 cur_uf, mask;
1281
1282	mask = ~(dep->interval - 1);
1283	cur_uf = event->parameters & mask;
1284
1285	__dwc3_gadget_start_isoc(dwc, dep, cur_uf);
1286}
1287
1288static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
1289{
1290	struct dwc3		*dwc = dep->dwc;
1291
1292	if (!dep->endpoint.desc) {
1293		dev_err(dwc->dev, "%s: can't queue to disabled endpoint\n",
1294				dep->name);
1295		return -ESHUTDOWN;
1296	}
1297
1298	if (WARN(req->dep != dep, "request %pK belongs to '%s'\n",
1299				&req->request, req->dep->name))
1300		return -EINVAL;
1301
1302	pm_runtime_get(dwc->dev);
1303
1304	req->request.actual	= 0;
1305	req->request.status	= -EINPROGRESS;
1306	req->direction		= dep->direction;
1307	req->epnum		= dep->number;
1308
1309	trace_dwc3_ep_queue(req);
1310
1311	list_add_tail(&req->list, &dep->pending_list);
1312
1313	/*
1314	 * NOTICE: Isochronous endpoints should NEVER be prestarted. We must
1315	 * wait for a XferNotReady event so we will know what's the current
1316	 * (micro-)frame number.
1317	 *
1318	 * Without this trick, we are very, very likely gonna get Bus Expiry
1319	 * errors which will force us issue EndTransfer command.
1320	 */
1321	if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1322		if ((dep->flags & DWC3_EP_PENDING_REQUEST)) {
1323			if (dep->flags & DWC3_EP_TRANSFER_STARTED) {
1324				dwc3_stop_active_transfer(dwc, dep->number, true);
1325				dep->flags = DWC3_EP_ENABLED;
1326			} else {
1327				u32 cur_uf;
1328
1329				cur_uf = __dwc3_gadget_get_frame(dwc);
1330				__dwc3_gadget_start_isoc(dwc, dep, cur_uf);
1331				dep->flags &= ~DWC3_EP_PENDING_REQUEST;
1332			}
1333			return 0;
1334		}
1335
1336		if ((dep->flags & DWC3_EP_BUSY) &&
1337		    !(dep->flags & DWC3_EP_MISSED_ISOC))
1338			goto out;
1339
1340		return 0;
1341	}
1342
1343out:
1344	return __dwc3_gadget_kick_transfer(dep);
1345}
1346
1347static int dwc3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
1348	gfp_t gfp_flags)
1349{
1350	struct dwc3_request		*req = to_dwc3_request(request);
1351	struct dwc3_ep			*dep = to_dwc3_ep(ep);
1352	struct dwc3			*dwc = dep->dwc;
1353
1354	unsigned long			flags;
1355
1356	int				ret;
1357
1358	spin_lock_irqsave(&dwc->lock, flags);
1359	ret = __dwc3_gadget_ep_queue(dep, req);
1360	spin_unlock_irqrestore(&dwc->lock, flags);
1361
1362	return ret;
1363}
1364
1365static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
1366		struct usb_request *request)
1367{
1368	struct dwc3_request		*req = to_dwc3_request(request);
1369	struct dwc3_request		*r = NULL;
1370
1371	struct dwc3_ep			*dep = to_dwc3_ep(ep);
1372	struct dwc3			*dwc = dep->dwc;
1373
1374	unsigned long			flags;
1375	int				ret = 0;
1376
1377	trace_dwc3_ep_dequeue(req);
1378
1379	spin_lock_irqsave(&dwc->lock, flags);
1380
1381	list_for_each_entry(r, &dep->pending_list, list) {
1382		if (r == req)
1383			break;
1384	}
1385
1386	if (r != req) {
1387		list_for_each_entry(r, &dep->started_list, list) {
1388			if (r == req)
1389				break;
1390		}
1391		if (r == req) {
1392			/* wait until it is processed */
1393			dwc3_stop_active_transfer(dwc, dep->number, true);
1394
1395			/*
1396			 * If request was already started, this means we had to
1397			 * stop the transfer. With that we also need to ignore
1398			 * all TRBs used by the request, however TRBs can only
1399			 * be modified after completion of END_TRANSFER
1400			 * command. So what we do here is that we wait for
1401			 * END_TRANSFER completion and only after that, we jump
1402			 * over TRBs by clearing HWO and incrementing dequeue
1403			 * pointer.
1404			 *
1405			 * Note that we have 2 possible types of transfers here:
1406			 *
1407			 * i) Linear buffer request
1408			 * ii) SG-list based request
1409			 *
1410			 * SG-list based requests will have r->num_pending_sgs
1411			 * set to a valid number (> 0). Linear requests,
1412			 * normally use a single TRB.
1413			 *
1414			 * For each of these two cases, if r->unaligned flag is
1415			 * set, one extra TRB has been used to align transfer
1416			 * size to wMaxPacketSize.
1417			 *
1418			 * All of these cases need to be taken into
1419			 * consideration so we don't mess up our TRB ring
1420			 * pointers.
1421			 */
1422			wait_event_lock_irq(dep->wait_end_transfer,
1423					!(dep->flags & DWC3_EP_END_TRANSFER_PENDING),
1424					dwc->lock);
1425
1426			if (!r->trb)
1427				goto out0;
1428
1429			if (r->num_pending_sgs) {
1430				struct dwc3_trb *trb;
1431				int i = 0;
1432
1433				for (i = 0; i < r->num_pending_sgs; i++) {
1434					trb = r->trb + i;
1435					trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
1436					dwc3_ep_inc_deq(dep);
1437				}
1438
1439				if (r->unaligned || r->zero) {
1440					trb = r->trb + r->num_pending_sgs + 1;
1441					trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
1442					dwc3_ep_inc_deq(dep);
1443				}
1444			} else {
1445				struct dwc3_trb *trb = r->trb;
1446
1447				trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
1448				dwc3_ep_inc_deq(dep);
1449
1450				if (r->unaligned || r->zero) {
1451					trb = r->trb + 1;
1452					trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
1453					dwc3_ep_inc_deq(dep);
1454				}
1455			}
1456			goto out1;
1457		}
1458		dev_err(dwc->dev, "request %pK was not queued to %s\n",
1459				request, ep->name);
1460		ret = -EINVAL;
1461		goto out0;
1462	}
1463
1464out1:
1465	/* giveback the request */
1466	dep->queued_requests--;
1467	dwc3_gadget_giveback(dep, req, -ECONNRESET);
1468
1469out0:
1470	spin_unlock_irqrestore(&dwc->lock, flags);
1471
1472	return ret;
1473}
1474
1475int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
1476{
1477	struct dwc3_gadget_ep_cmd_params	params;
1478	struct dwc3				*dwc = dep->dwc;
1479	int					ret;
1480
1481	if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
1482		dev_err(dwc->dev, "%s is of Isochronous type\n", dep->name);
1483		return -EINVAL;
1484	}
1485
1486	memset(&params, 0x00, sizeof(params));
1487
1488	if (value) {
1489		struct dwc3_trb *trb;
1490
1491		unsigned transfer_in_flight;
1492		unsigned started;
1493
1494		if (dep->flags & DWC3_EP_STALL)
1495			return 0;
1496
1497		if (dep->number > 1)
1498			trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
1499		else
1500			trb = &dwc->ep0_trb[dep->trb_enqueue];
1501
1502		transfer_in_flight = trb->ctrl & DWC3_TRB_CTRL_HWO;
1503		started = !list_empty(&dep->started_list);
1504
1505		if (!protocol && ((dep->direction && transfer_in_flight) ||
1506				(!dep->direction && started))) {
1507			return -EAGAIN;
1508		}
1509
1510		ret = dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETSTALL,
1511				&params);
1512		if (ret)
1513			dev_err(dwc->dev, "failed to set STALL on %s\n",
1514					dep->name);
1515		else
1516			dep->flags |= DWC3_EP_STALL;
1517	} else {
1518		if (!(dep->flags & DWC3_EP_STALL))
1519			return 0;
1520
1521		ret = dwc3_send_clear_stall_ep_cmd(dep);
1522		if (ret)
1523			dev_err(dwc->dev, "failed to clear STALL on %s\n",
1524					dep->name);
1525		else
1526			dep->flags &= ~(DWC3_EP_STALL | DWC3_EP_WEDGE);
1527	}
1528
1529	return ret;
1530}
1531
1532static int dwc3_gadget_ep_set_halt(struct usb_ep *ep, int value)
1533{
1534	struct dwc3_ep			*dep = to_dwc3_ep(ep);
1535	struct dwc3			*dwc = dep->dwc;
1536
1537	unsigned long			flags;
1538
1539	int				ret;
1540
1541	spin_lock_irqsave(&dwc->lock, flags);
1542	ret = __dwc3_gadget_ep_set_halt(dep, value, false);
1543	spin_unlock_irqrestore(&dwc->lock, flags);
1544
1545	return ret;
1546}
1547
1548static int dwc3_gadget_ep_set_wedge(struct usb_ep *ep)
1549{
1550	struct dwc3_ep			*dep = to_dwc3_ep(ep);
1551	struct dwc3			*dwc = dep->dwc;
1552	unsigned long			flags;
1553	int				ret;
1554
1555	spin_lock_irqsave(&dwc->lock, flags);
1556	dep->flags |= DWC3_EP_WEDGE;
1557
1558	if (dep->number == 0 || dep->number == 1)
1559		ret = __dwc3_gadget_ep0_set_halt(ep, 1);
1560	else
1561		ret = __dwc3_gadget_ep_set_halt(dep, 1, false);
1562	spin_unlock_irqrestore(&dwc->lock, flags);
1563
1564	return ret;
1565}
1566
1567/* -------------------------------------------------------------------------- */
1568
1569static struct usb_endpoint_descriptor dwc3_gadget_ep0_desc = {
1570	.bLength	= USB_DT_ENDPOINT_SIZE,
1571	.bDescriptorType = USB_DT_ENDPOINT,
1572	.bmAttributes	= USB_ENDPOINT_XFER_CONTROL,
1573};
1574
1575static const struct usb_ep_ops dwc3_gadget_ep0_ops = {
1576	.enable		= dwc3_gadget_ep0_enable,
1577	.disable	= dwc3_gadget_ep0_disable,
1578	.alloc_request	= dwc3_gadget_ep_alloc_request,
1579	.free_request	= dwc3_gadget_ep_free_request,
1580	.queue		= dwc3_gadget_ep0_queue,
1581	.dequeue	= dwc3_gadget_ep_dequeue,
1582	.set_halt	= dwc3_gadget_ep0_set_halt,
1583	.set_wedge	= dwc3_gadget_ep_set_wedge,
1584};
1585
1586static const struct usb_ep_ops dwc3_gadget_ep_ops = {
1587	.enable		= dwc3_gadget_ep_enable,
1588	.disable	= dwc3_gadget_ep_disable,
1589	.alloc_request	= dwc3_gadget_ep_alloc_request,
1590	.free_request	= dwc3_gadget_ep_free_request,
1591	.queue		= dwc3_gadget_ep_queue,
1592	.dequeue	= dwc3_gadget_ep_dequeue,
1593	.set_halt	= dwc3_gadget_ep_set_halt,
1594	.set_wedge	= dwc3_gadget_ep_set_wedge,
1595};
1596
1597/* -------------------------------------------------------------------------- */
1598
1599static int dwc3_gadget_get_frame(struct usb_gadget *g)
1600{
1601	struct dwc3		*dwc = gadget_to_dwc(g);
1602
1603	return __dwc3_gadget_get_frame(dwc);
1604}
1605
1606static int __dwc3_gadget_wakeup(struct dwc3 *dwc)
1607{
1608	int			retries;
1609
1610	int			ret;
1611	u32			reg;
1612
1613	u8			link_state;
1614	u8			speed;
1615
1616	/*
1617	 * According to the Databook Remote wakeup request should
1618	 * be issued only when the device is in early suspend state.
1619	 *
1620	 * We can check that via USB Link State bits in DSTS register.
1621	 */
1622	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1623
1624	speed = reg & DWC3_DSTS_CONNECTSPD;
1625	if ((speed == DWC3_DSTS_SUPERSPEED) ||
1626	    (speed == DWC3_DSTS_SUPERSPEED_PLUS))
1627		return 0;
1628
1629	link_state = DWC3_DSTS_USBLNKST(reg);
1630
1631	switch (link_state) {
1632	case DWC3_LINK_STATE_RX_DET:	/* in HS, means Early Suspend */
1633	case DWC3_LINK_STATE_U3:	/* in HS, means SUSPEND */
1634		break;
1635	default:
1636		return -EINVAL;
1637	}
1638
1639	ret = dwc3_gadget_set_link_state(dwc, DWC3_LINK_STATE_RECOV);
1640	if (ret < 0) {
1641		dev_err(dwc->dev, "failed to put link in Recovery\n");
1642		return ret;
1643	}
1644
1645	/* Recent versions do this automatically */
1646	if (dwc->revision < DWC3_REVISION_194A) {
1647		/* write zeroes to Link Change Request */
1648		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1649		reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
1650		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1651	}
1652
1653	/* poll until Link State changes to ON */
1654	retries = 20000;
1655
1656	while (retries--) {
1657		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1658
1659		/* in HS, means ON */
1660		if (DWC3_DSTS_USBLNKST(reg) == DWC3_LINK_STATE_U0)
1661			break;
1662	}
1663
1664	if (DWC3_DSTS_USBLNKST(reg) != DWC3_LINK_STATE_U0) {
1665		dev_err(dwc->dev, "failed to send remote wakeup\n");
1666		return -EINVAL;
1667	}
1668
1669	return 0;
1670}
1671
1672static int dwc3_gadget_wakeup(struct usb_gadget *g)
1673{
1674	struct dwc3		*dwc = gadget_to_dwc(g);
1675	unsigned long		flags;
1676	int			ret;
1677
1678	spin_lock_irqsave(&dwc->lock, flags);
1679	ret = __dwc3_gadget_wakeup(dwc);
1680	spin_unlock_irqrestore(&dwc->lock, flags);
1681
1682	return ret;
1683}
1684
1685static int dwc3_gadget_set_selfpowered(struct usb_gadget *g,
1686		int is_selfpowered)
1687{
1688	struct dwc3		*dwc = gadget_to_dwc(g);
1689	unsigned long		flags;
1690
1691	spin_lock_irqsave(&dwc->lock, flags);
1692	g->is_selfpowered = !!is_selfpowered;
1693	spin_unlock_irqrestore(&dwc->lock, flags);
1694
1695	return 0;
1696}
1697
1698static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
1699{
1700	u32			reg;
1701	u32			timeout = 500;
1702
1703	if (pm_runtime_suspended(dwc->dev))
1704		return 0;
1705
1706	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
1707	if (is_on) {
1708		if (dwc->revision <= DWC3_REVISION_187A) {
1709			reg &= ~DWC3_DCTL_TRGTULST_MASK;
1710			reg |= DWC3_DCTL_TRGTULST_RX_DET;
1711		}
1712
1713		if (dwc->revision >= DWC3_REVISION_194A)
1714			reg &= ~DWC3_DCTL_KEEP_CONNECT;
1715		reg |= DWC3_DCTL_RUN_STOP;
1716
1717		if (dwc->has_hibernation)
1718			reg |= DWC3_DCTL_KEEP_CONNECT;
1719
1720		dwc->pullups_connected = true;
1721	} else {
1722		reg &= ~DWC3_DCTL_RUN_STOP;
1723
1724		if (dwc->has_hibernation && !suspend)
1725			reg &= ~DWC3_DCTL_KEEP_CONNECT;
1726
1727		dwc->pullups_connected = false;
1728	}
1729
1730	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
1731
1732	do {
1733		reg = dwc3_readl(dwc->regs, DWC3_DSTS);
1734		reg &= DWC3_DSTS_DEVCTRLHLT;
1735	} while (--timeout && !(!is_on ^ !reg));
1736
1737	if (!timeout)
1738		return -ETIMEDOUT;
1739
1740	return 0;
1741}
1742
1743static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
1744{
1745	struct dwc3		*dwc = gadget_to_dwc(g);
1746	unsigned long		flags;
1747	int			ret;
1748
1749	is_on = !!is_on;
1750
1751	/*
1752	 * Per databook, when we want to stop the gadget, if a control transfer
1753	 * is still in process, complete it and get the core into setup phase.
1754	 */
1755	if (!is_on && dwc->ep0state != EP0_SETUP_PHASE) {
1756		reinit_completion(&dwc->ep0_in_setup);
1757
1758		ret = wait_for_completion_timeout(&dwc->ep0_in_setup,
1759				msecs_to_jiffies(DWC3_PULL_UP_TIMEOUT));
1760		if (ret == 0) {
1761			dev_err(dwc->dev, "timed out waiting for SETUP phase\n");
1762			return -ETIMEDOUT;
1763		}
1764	}
1765
1766	spin_lock_irqsave(&dwc->lock, flags);
1767	ret = dwc3_gadget_run_stop(dwc, is_on, false);
1768	spin_unlock_irqrestore(&dwc->lock, flags);
1769
1770	return ret;
1771}
1772
1773static void dwc3_gadget_enable_irq(struct dwc3 *dwc)
1774{
1775	u32			reg;
1776
1777	/* Enable all but Start and End of Frame IRQs */
1778	reg = (DWC3_DEVTEN_VNDRDEVTSTRCVEDEN |
1779			DWC3_DEVTEN_EVNTOVERFLOWEN |
1780			DWC3_DEVTEN_CMDCMPLTEN |
1781			DWC3_DEVTEN_ERRTICERREN |
1782			DWC3_DEVTEN_WKUPEVTEN |
1783			DWC3_DEVTEN_CONNECTDONEEN |
1784			DWC3_DEVTEN_USBRSTEN |
1785			DWC3_DEVTEN_DISCONNEVTEN);
1786
1787	if (dwc->revision < DWC3_REVISION_250A)
1788		reg |= DWC3_DEVTEN_ULSTCNGEN;
1789
1790	dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
1791}
1792
1793static void dwc3_gadget_disable_irq(struct dwc3 *dwc)
1794{
1795	/* mask all interrupts */
1796	dwc3_writel(dwc->regs, DWC3_DEVTEN, 0x00);
1797}
1798
1799static irqreturn_t dwc3_interrupt(int irq, void *_dwc);
1800static irqreturn_t dwc3_thread_interrupt(int irq, void *_dwc);
1801
1802/**
1803 * dwc3_gadget_setup_nump - calculate and initialize NUMP field of %DWC3_DCFG
1804 * @dwc: pointer to our context structure
1805 *
1806 * The following looks like complex but it's actually very simple. In order to
1807 * calculate the number of packets we can burst at once on OUT transfers, we're
1808 * gonna use RxFIFO size.
1809 *
1810 * To calculate RxFIFO size we need two numbers:
1811 * MDWIDTH = size, in bits, of the internal memory bus
1812 * RAM2_DEPTH = depth, in MDWIDTH, of internal RAM2 (where RxFIFO sits)
1813 *
1814 * Given these two numbers, the formula is simple:
1815 *
1816 * RxFIFO Size = (RAM2_DEPTH * MDWIDTH / 8) - 24 - 16;
1817 *
1818 * 24 bytes is for 3x SETUP packets
1819 * 16 bytes is a clock domain crossing tolerance
1820 *
1821 * Given RxFIFO Size, NUMP = RxFIFOSize / 1024;
1822 */
1823static void dwc3_gadget_setup_nump(struct dwc3 *dwc)
1824{
1825	u32 ram2_depth;
1826	u32 mdwidth;
1827	u32 nump;
1828	u32 reg;
1829
1830	ram2_depth = DWC3_GHWPARAMS7_RAM2_DEPTH(dwc->hwparams.hwparams7);
1831	mdwidth = DWC3_GHWPARAMS0_MDWIDTH(dwc->hwparams.hwparams0);
1832
1833	nump = ((ram2_depth * mdwidth / 8) - 24 - 16) / 1024;
1834	nump = min_t(u32, nump, 16);
1835
1836	/* update NumP */
1837	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
1838	reg &= ~DWC3_DCFG_NUMP_MASK;
1839	reg |= nump << DWC3_DCFG_NUMP_SHIFT;
1840	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
1841}
1842
1843static int __dwc3_gadget_start(struct dwc3 *dwc)
1844{
1845	struct dwc3_ep		*dep;
1846	int			ret = 0;
1847	u32			reg;
1848
1849	/*
1850	 * Use IMOD if enabled via dwc->imod_interval. Otherwise, if
1851	 * the core supports IMOD, disable it.
1852	 */
1853	if (dwc->imod_interval) {
1854		dwc3_writel(dwc->regs, DWC3_DEV_IMOD(0), dwc->imod_interval);
1855		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), DWC3_GEVNTCOUNT_EHB);
1856	} else if (dwc3_has_imod(dwc)) {
1857		dwc3_writel(dwc->regs, DWC3_DEV_IMOD(0), 0);
1858	}
1859
1860	/*
1861	 * We are telling dwc3 that we want to use DCFG.NUMP as ACK TP's NUMP
1862	 * field instead of letting dwc3 itself calculate that automatically.
1863	 *
1864	 * This way, we maximize the chances that we'll be able to get several
1865	 * bursts of data without going through any sort of endpoint throttling.
1866	 */
1867	reg = dwc3_readl(dwc->regs, DWC3_GRXTHRCFG);
1868	if (dwc3_is_usb31(dwc))
1869		reg &= ~DWC31_GRXTHRCFG_PKTCNTSEL;
1870	else
1871		reg &= ~DWC3_GRXTHRCFG_PKTCNTSEL;
1872
1873	dwc3_writel(dwc->regs, DWC3_GRXTHRCFG, reg);
1874
1875	dwc3_gadget_setup_nump(dwc);
1876
1877	/* Start with SuperSpeed Default */
1878	dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
1879
1880	dep = dwc->eps[0];
1881	ret = __dwc3_gadget_ep_enable(dep, false, false);
1882	if (ret) {
1883		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1884		goto err0;
1885	}
1886
1887	dep = dwc->eps[1];
1888	ret = __dwc3_gadget_ep_enable(dep, false, false);
1889	if (ret) {
1890		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
1891		goto err1;
1892	}
1893
1894	/* begin to receive SETUP packets */
1895	dwc->ep0state = EP0_SETUP_PHASE;
1896	dwc3_ep0_out_start(dwc);
1897
1898	dwc3_gadget_enable_irq(dwc);
1899
1900	return 0;
1901
1902err1:
1903	__dwc3_gadget_ep_disable(dwc->eps[0]);
1904
1905err0:
1906	return ret;
1907}
1908
1909static int dwc3_gadget_start(struct usb_gadget *g,
1910		struct usb_gadget_driver *driver)
1911{
1912	struct dwc3		*dwc = gadget_to_dwc(g);
1913	unsigned long		flags;
1914	int			ret = 0;
1915	int			irq;
1916
1917	irq = dwc->irq_gadget;
1918	ret = request_threaded_irq(irq, dwc3_interrupt, dwc3_thread_interrupt,
1919			IRQF_SHARED, "dwc3", dwc->ev_buf);
1920	if (ret) {
1921		dev_err(dwc->dev, "failed to request irq #%d --> %d\n",
1922				irq, ret);
1923		goto err0;
1924	}
1925
1926	spin_lock_irqsave(&dwc->lock, flags);
1927	if (dwc->gadget_driver) {
1928		dev_err(dwc->dev, "%s is already bound to %s\n",
1929				dwc->gadget.name,
1930				dwc->gadget_driver->driver.name);
1931		ret = -EBUSY;
1932		goto err1;
1933	}
1934
1935	dwc->gadget_driver	= driver;
1936
1937	if (pm_runtime_active(dwc->dev))
1938		__dwc3_gadget_start(dwc);
1939
1940	spin_unlock_irqrestore(&dwc->lock, flags);
1941
1942	return 0;
1943
1944err1:
1945	spin_unlock_irqrestore(&dwc->lock, flags);
1946	free_irq(irq, dwc);
1947
1948err0:
1949	return ret;
1950}
1951
1952static void __dwc3_gadget_stop(struct dwc3 *dwc)
1953{
1954	dwc3_gadget_disable_irq(dwc);
1955	__dwc3_gadget_ep_disable(dwc->eps[0]);
1956	__dwc3_gadget_ep_disable(dwc->eps[1]);
1957}
1958
1959static int dwc3_gadget_stop(struct usb_gadget *g)
1960{
1961	struct dwc3		*dwc = gadget_to_dwc(g);
1962	unsigned long		flags;
1963	int			epnum;
1964	u32			tmo_eps = 0;
1965
1966	spin_lock_irqsave(&dwc->lock, flags);
1967
1968	if (pm_runtime_suspended(dwc->dev))
1969		goto out;
1970
1971	__dwc3_gadget_stop(dwc);
1972
1973	for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
1974		struct dwc3_ep  *dep = dwc->eps[epnum];
1975		int ret;
1976
1977		if (!dep)
1978			continue;
1979
1980		if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
1981			continue;
1982
1983		ret = wait_event_interruptible_lock_irq_timeout(dep->wait_end_transfer,
1984			    !(dep->flags & DWC3_EP_END_TRANSFER_PENDING),
1985			    dwc->lock, msecs_to_jiffies(5));
1986
1987		if (ret <= 0) {
1988			/* Timed out or interrupted! There's nothing much
1989			 * we can do so we just log here and print which
1990			 * endpoints timed out at the end.
1991			 */
1992			tmo_eps |= 1 << epnum;
1993			dep->flags &= DWC3_EP_END_TRANSFER_PENDING;
1994		}
1995	}
1996
1997	if (tmo_eps) {
1998		dev_err(dwc->dev,
1999			"end transfer timed out on endpoints 0x%x [bitmap]\n",
2000			tmo_eps);
2001	}
2002
2003out:
2004	dwc->gadget_driver	= NULL;
2005	spin_unlock_irqrestore(&dwc->lock, flags);
2006
2007	free_irq(dwc->irq_gadget, dwc->ev_buf);
2008
2009	return 0;
2010}
2011
2012static void dwc3_gadget_set_speed(struct usb_gadget *g,
2013				  enum usb_device_speed speed)
2014{
2015	struct dwc3		*dwc = gadget_to_dwc(g);
2016	unsigned long		flags;
2017	u32			reg;
2018
2019	spin_lock_irqsave(&dwc->lock, flags);
2020	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2021	reg &= ~(DWC3_DCFG_SPEED_MASK);
2022
2023	/*
2024	 * WORKAROUND: DWC3 revision < 2.20a have an issue
2025	 * which would cause metastability state on Run/Stop
2026	 * bit if we try to force the IP to USB2-only mode.
2027	 *
2028	 * Because of that, we cannot configure the IP to any
2029	 * speed other than the SuperSpeed
2030	 *
2031	 * Refers to:
2032	 *
2033	 * STAR#9000525659: Clock Domain Crossing on DCTL in
2034	 * USB 2.0 Mode
2035	 */
2036	if (dwc->revision < DWC3_REVISION_220A &&
2037	    !dwc->dis_metastability_quirk) {
2038		reg |= DWC3_DCFG_SUPERSPEED;
2039	} else {
2040		switch (speed) {
2041		case USB_SPEED_LOW:
2042			reg |= DWC3_DCFG_LOWSPEED;
2043			break;
2044		case USB_SPEED_FULL:
2045			reg |= DWC3_DCFG_FULLSPEED;
2046			break;
2047		case USB_SPEED_HIGH:
2048			reg |= DWC3_DCFG_HIGHSPEED;
2049			break;
2050		case USB_SPEED_SUPER:
2051			reg |= DWC3_DCFG_SUPERSPEED;
2052			break;
2053		case USB_SPEED_SUPER_PLUS:
2054			if (dwc3_is_usb31(dwc))
2055				reg |= DWC3_DCFG_SUPERSPEED_PLUS;
2056			else
2057				reg |= DWC3_DCFG_SUPERSPEED;
2058			break;
2059		default:
2060			dev_err(dwc->dev, "invalid speed (%d)\n", speed);
2061
2062			if (dwc->revision & DWC3_REVISION_IS_DWC31)
2063				reg |= DWC3_DCFG_SUPERSPEED_PLUS;
2064			else
2065				reg |= DWC3_DCFG_SUPERSPEED;
2066		}
2067	}
2068	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2069
2070	spin_unlock_irqrestore(&dwc->lock, flags);
2071}
2072
2073static const struct usb_gadget_ops dwc3_gadget_ops = {
2074	.get_frame		= dwc3_gadget_get_frame,
2075	.wakeup			= dwc3_gadget_wakeup,
2076	.set_selfpowered	= dwc3_gadget_set_selfpowered,
2077	.pullup			= dwc3_gadget_pullup,
2078	.udc_start		= dwc3_gadget_start,
2079	.udc_stop		= dwc3_gadget_stop,
2080	.udc_set_speed		= dwc3_gadget_set_speed,
2081};
2082
2083/* -------------------------------------------------------------------------- */
2084
2085static int dwc3_gadget_init_endpoints(struct dwc3 *dwc, u8 total)
2086{
2087	struct dwc3_ep			*dep;
2088	u8				epnum;
2089
2090	INIT_LIST_HEAD(&dwc->gadget.ep_list);
2091
2092	for (epnum = 0; epnum < total; epnum++) {
2093		bool			direction = epnum & 1;
2094		u8			num = epnum >> 1;
2095
2096		dep = kzalloc(sizeof(*dep), GFP_KERNEL);
2097		if (!dep)
2098			return -ENOMEM;
2099
2100		dep->dwc = dwc;
2101		dep->number = epnum;
2102		dep->direction = direction;
2103		dep->regs = dwc->regs + DWC3_DEP_BASE(epnum);
2104		dwc->eps[epnum] = dep;
2105
2106		snprintf(dep->name, sizeof(dep->name), "ep%u%s", num,
2107				direction ? "in" : "out");
2108
2109		dep->endpoint.name = dep->name;
2110
2111		if (!(dep->number > 1)) {
2112			dep->endpoint.desc = &dwc3_gadget_ep0_desc;
2113			dep->endpoint.comp_desc = NULL;
2114		}
2115
2116		spin_lock_init(&dep->lock);
2117
2118		if (num == 0) {
2119			usb_ep_set_maxpacket_limit(&dep->endpoint, 512);
2120			dep->endpoint.maxburst = 1;
2121			dep->endpoint.ops = &dwc3_gadget_ep0_ops;
2122			if (!direction)
2123				dwc->gadget.ep0 = &dep->endpoint;
2124		} else if (direction) {
2125			int mdwidth;
2126			int kbytes;
2127			int size;
2128			int ret;
2129
2130			mdwidth = DWC3_MDWIDTH(dwc->hwparams.hwparams0);
2131			/* MDWIDTH is represented in bits, we need it in bytes */
2132			mdwidth /= 8;
2133
2134			size = dwc3_readl(dwc->regs, DWC3_GTXFIFOSIZ(num));
2135			if (dwc3_is_usb31(dwc))
2136				size = DWC31_GTXFIFOSIZ_TXFDEF(size);
2137			else
2138				size = DWC3_GTXFIFOSIZ_TXFDEF(size);
2139
2140			/* FIFO Depth is in MDWDITH bytes. Multiply */
2141			size *= mdwidth;
2142
2143			kbytes = size / 1024;
2144			if (kbytes == 0)
2145				kbytes = 1;
2146
2147			/*
2148			 * FIFO sizes account an extra MDWIDTH * (kbytes + 1) bytes for
2149			 * internal overhead. We don't really know how these are used,
2150			 * but documentation say it exists.
2151			 */
2152			size -= mdwidth * (kbytes + 1);
2153			size /= kbytes;
2154
2155			usb_ep_set_maxpacket_limit(&dep->endpoint, size);
2156
2157			dep->endpoint.max_streams = 15;
2158			dep->endpoint.ops = &dwc3_gadget_ep_ops;
2159			list_add_tail(&dep->endpoint.ep_list,
2160					&dwc->gadget.ep_list);
2161
2162			ret = dwc3_alloc_trb_pool(dep);
2163			if (ret)
2164				return ret;
2165		} else {
2166			int		ret;
2167
2168			usb_ep_set_maxpacket_limit(&dep->endpoint, 1024);
2169			dep->endpoint.max_streams = 15;
2170			dep->endpoint.ops = &dwc3_gadget_ep_ops;
2171			list_add_tail(&dep->endpoint.ep_list,
2172					&dwc->gadget.ep_list);
2173
2174			ret = dwc3_alloc_trb_pool(dep);
2175			if (ret)
2176				return ret;
2177		}
2178
2179		if (num == 0) {
2180			dep->endpoint.caps.type_control = true;
2181		} else {
2182			dep->endpoint.caps.type_iso = true;
2183			dep->endpoint.caps.type_bulk = true;
2184			dep->endpoint.caps.type_int = true;
2185		}
2186
2187		dep->endpoint.caps.dir_in = direction;
2188		dep->endpoint.caps.dir_out = !direction;
2189
2190		INIT_LIST_HEAD(&dep->pending_list);
2191		INIT_LIST_HEAD(&dep->started_list);
2192	}
2193
2194	return 0;
2195}
2196
2197static void dwc3_gadget_free_endpoints(struct dwc3 *dwc)
2198{
2199	struct dwc3_ep			*dep;
2200	u8				epnum;
2201
2202	for (epnum = 0; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
2203		dep = dwc->eps[epnum];
2204		if (!dep)
2205			continue;
2206		/*
2207		 * Physical endpoints 0 and 1 are special; they form the
2208		 * bi-directional USB endpoint 0.
2209		 *
2210		 * For those two physical endpoints, we don't allocate a TRB
2211		 * pool nor do we add them the endpoints list. Due to that, we
2212		 * shouldn't do these two operations otherwise we would end up
2213		 * with all sorts of bugs when removing dwc3.ko.
2214		 */
2215		if (epnum != 0 && epnum != 1) {
2216			dwc3_free_trb_pool(dep);
2217			list_del(&dep->endpoint.ep_list);
2218		}
2219
2220		kfree(dep);
2221	}
2222}
2223
2224/* -------------------------------------------------------------------------- */
2225
2226static int __dwc3_cleanup_done_trbs(struct dwc3 *dwc, struct dwc3_ep *dep,
2227		struct dwc3_request *req, struct dwc3_trb *trb,
2228		const struct dwc3_event_depevt *event, int status,
2229		int chain)
2230{
2231	unsigned int		count;
2232	unsigned int		s_pkt = 0;
2233	unsigned int		trb_status;
2234
2235	dwc3_ep_inc_deq(dep);
2236
2237	if (req->trb == trb)
2238		dep->queued_requests--;
2239
2240	trace_dwc3_complete_trb(dep, trb);
2241
2242	/*
2243	 * If we're in the middle of series of chained TRBs and we
2244	 * receive a short transfer along the way, DWC3 will skip
2245	 * through all TRBs including the last TRB in the chain (the
2246	 * where CHN bit is zero. DWC3 will also avoid clearing HWO
2247	 * bit and SW has to do it manually.
2248	 *
2249	 * We're going to do that here to avoid problems of HW trying
2250	 * to use bogus TRBs for transfers.
2251	 */
2252	if (chain && (trb->ctrl & DWC3_TRB_CTRL_HWO))
2253		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
2254
2255	/*
2256	 * If we're dealing with unaligned size OUT transfer, we will be left
2257	 * with one TRB pending in the ring. We need to manually clear HWO bit
2258	 * from that TRB.
2259	 */
2260	if ((req->zero || req->unaligned) && (trb->ctrl & DWC3_TRB_CTRL_HWO)) {
2261		trb->ctrl &= ~DWC3_TRB_CTRL_HWO;
2262		return 1;
2263	}
2264
2265	count = trb->size & DWC3_TRB_SIZE_MASK;
2266	req->remaining += count;
2267
2268	if ((trb->ctrl & DWC3_TRB_CTRL_HWO) && status != -ESHUTDOWN)
2269		return 1;
2270
2271	if (dep->direction) {
2272		if (count) {
2273			trb_status = DWC3_TRB_SIZE_TRBSTS(trb->size);
2274			if (trb_status == DWC3_TRBSTS_MISSED_ISOC) {
2275				/*
2276				 * If missed isoc occurred and there is
2277				 * no request queued then issue END
2278				 * TRANSFER, so that core generates
2279				 * next xfernotready and we will issue
2280				 * a fresh START TRANSFER.
2281				 * If there are still queued request
2282				 * then wait, do not issue either END
2283				 * or UPDATE TRANSFER, just attach next
2284				 * request in pending_list during
2285				 * giveback.If any future queued request
2286				 * is successfully transferred then we
2287				 * will issue UPDATE TRANSFER for all
2288				 * request in the pending_list.
2289				 */
2290				dep->flags |= DWC3_EP_MISSED_ISOC;
2291			} else {
2292				dev_err(dwc->dev, "incomplete IN transfer %s\n",
2293						dep->name);
2294				status = -ECONNRESET;
2295			}
2296		} else {
2297			dep->flags &= ~DWC3_EP_MISSED_ISOC;
2298		}
2299	} else {
2300		if (count && (event->status & DEPEVT_STATUS_SHORT))
2301			s_pkt = 1;
2302	}
2303
2304	if (s_pkt && !chain)
2305		return 1;
2306
2307	if ((event->status & DEPEVT_STATUS_IOC) &&
2308			(trb->ctrl & DWC3_TRB_CTRL_IOC))
2309		return 1;
2310
2311	return 0;
2312}
2313
2314static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
2315		const struct dwc3_event_depevt *event, int status)
2316{
2317	struct dwc3_request	*req, *n;
2318	struct dwc3_trb		*trb;
2319	bool			ioc = false;
2320	int			ret = 0;
2321
2322	list_for_each_entry_safe(req, n, &dep->started_list, list) {
2323		unsigned length;
2324		int chain;
2325
2326		length = req->request.length;
2327		chain = req->num_pending_sgs > 0;
2328		if (chain) {
2329			struct scatterlist *sg = req->sg;
2330			struct scatterlist *s;
2331			unsigned int pending = req->num_pending_sgs;
2332			unsigned int i;
2333
2334			for_each_sg(sg, s, pending, i) {
2335				trb = &dep->trb_pool[dep->trb_dequeue];
2336
2337				if (trb->ctrl & DWC3_TRB_CTRL_HWO)
2338					break;
2339
2340				req->sg = sg_next(s);
2341				req->num_pending_sgs--;
2342
2343				ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
2344						event, status, chain);
2345				if (ret)
2346					break;
2347			}
2348		} else {
2349			trb = &dep->trb_pool[dep->trb_dequeue];
2350			ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
2351					event, status, chain);
2352		}
2353
2354		if (req->unaligned || req->zero) {
2355			trb = &dep->trb_pool[dep->trb_dequeue];
2356			ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb,
2357					event, status, false);
2358			req->unaligned = false;
2359			req->zero = false;
2360		}
2361
2362		req->request.actual = length - req->remaining;
2363
2364		if ((req->request.actual < length) && req->num_pending_sgs)
2365			return __dwc3_gadget_kick_transfer(dep);
2366
2367		dwc3_gadget_giveback(dep, req, status);
2368
2369		if (ret) {
2370			if ((event->status & DEPEVT_STATUS_IOC) &&
2371			    (trb->ctrl & DWC3_TRB_CTRL_IOC))
2372				ioc = true;
2373			break;
2374		}
2375	}
2376
2377	/*
2378	 * Our endpoint might get disabled by another thread during
2379	 * dwc3_gadget_giveback(). If that happens, we're just gonna return 1
2380	 * early on so DWC3_EP_BUSY flag gets cleared
2381	 */
2382	if (!dep->endpoint.desc)
2383		return 1;
2384
2385	if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
2386			list_empty(&dep->started_list)) {
2387		if (list_empty(&dep->pending_list)) {
2388			/*
2389			 * If there is no entry in request list then do
2390			 * not issue END TRANSFER now. Just set PENDING
2391			 * flag, so that END TRANSFER is issued when an
2392			 * entry is added into request list.
2393			 */
2394			dep->flags = DWC3_EP_PENDING_REQUEST;
2395		} else {
2396			dwc3_stop_active_transfer(dwc, dep->number, true);
2397			dep->flags = DWC3_EP_ENABLED;
2398		}
2399		return 1;
2400	}
2401
2402	if (usb_endpoint_xfer_isoc(dep->endpoint.desc) && ioc)
2403		return 0;
2404
2405	return 1;
2406}
2407
2408static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc,
2409		struct dwc3_ep *dep, const struct dwc3_event_depevt *event)
2410{
2411	unsigned		status = 0;
2412	int			clean_busy;
2413	u32			is_xfer_complete;
2414
2415	is_xfer_complete = (event->endpoint_event == DWC3_DEPEVT_XFERCOMPLETE);
2416
2417	if (event->status & DEPEVT_STATUS_BUSERR)
2418		status = -ECONNRESET;
2419
2420	clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status);
2421	if (clean_busy && (!dep->endpoint.desc || is_xfer_complete ||
2422				usb_endpoint_xfer_isoc(dep->endpoint.desc)))
2423		dep->flags &= ~DWC3_EP_BUSY;
2424
2425	/*
2426	 * WORKAROUND: This is the 2nd half of U1/U2 -> U0 workaround.
2427	 * See dwc3_gadget_linksts_change_interrupt() for 1st half.
2428	 */
2429	if (dwc->revision < DWC3_REVISION_183A) {
2430		u32		reg;
2431		int		i;
2432
2433		for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
2434			dep = dwc->eps[i];
2435
2436			if (!(dep->flags & DWC3_EP_ENABLED))
2437				continue;
2438
2439			if (!list_empty(&dep->started_list))
2440				return;
2441		}
2442
2443		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2444		reg |= dwc->u1u2;
2445		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2446
2447		dwc->u1u2 = 0;
2448	}
2449
2450	/*
2451	 * Our endpoint might get disabled by another thread during
2452	 * dwc3_gadget_giveback(). If that happens, we're just gonna return 1
2453	 * early on so DWC3_EP_BUSY flag gets cleared
2454	 */
2455	if (!dep->endpoint.desc)
2456		return;
2457
2458	if (!usb_endpoint_xfer_isoc(dep->endpoint.desc))
2459		__dwc3_gadget_kick_transfer(dep);
2460}
2461
2462static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
2463		const struct dwc3_event_depevt *event)
2464{
2465	struct dwc3_ep		*dep;
2466	u8			epnum = event->endpoint_number;
2467	u8			cmd;
2468
2469	dep = dwc->eps[epnum];
2470
2471	if (!(dep->flags & DWC3_EP_ENABLED)) {
2472		if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
2473			return;
2474
2475		/* Handle only EPCMDCMPLT when EP disabled */
2476		if (event->endpoint_event != DWC3_DEPEVT_EPCMDCMPLT)
2477			return;
2478	}
2479
2480	if (epnum == 0 || epnum == 1) {
2481		dwc3_ep0_interrupt(dwc, event);
2482		return;
2483	}
2484
2485	switch (event->endpoint_event) {
2486	case DWC3_DEPEVT_XFERCOMPLETE:
2487		dep->resource_index = 0;
2488
2489		if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
2490			dev_err(dwc->dev, "XferComplete for Isochronous endpoint\n");
2491			return;
2492		}
2493
2494		dwc3_endpoint_transfer_complete(dwc, dep, event);
2495		break;
2496	case DWC3_DEPEVT_XFERINPROGRESS:
2497		dwc3_endpoint_transfer_complete(dwc, dep, event);
2498		break;
2499	case DWC3_DEPEVT_XFERNOTREADY:
2500		if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
2501			dwc3_gadget_start_isoc(dwc, dep, event);
2502		else
2503			__dwc3_gadget_kick_transfer(dep);
2504
2505		break;
2506	case DWC3_DEPEVT_STREAMEVT:
2507		if (!usb_endpoint_xfer_bulk(dep->endpoint.desc)) {
2508			dev_err(dwc->dev, "Stream event for non-Bulk %s\n",
2509					dep->name);
2510			return;
2511		}
2512		break;
2513	case DWC3_DEPEVT_EPCMDCMPLT:
2514		cmd = DEPEVT_PARAMETER_CMD(event->parameters);
2515
2516		if (cmd == DWC3_DEPCMD_ENDTRANSFER) {
2517			dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;
2518			wake_up(&dep->wait_end_transfer);
2519		}
2520		break;
2521	case DWC3_DEPEVT_RXTXFIFOEVT:
2522		break;
2523	}
2524}
2525
2526static void dwc3_disconnect_gadget(struct dwc3 *dwc)
2527{
2528	if (dwc->gadget_driver && dwc->gadget_driver->disconnect) {
2529		spin_unlock(&dwc->lock);
2530		dwc->gadget_driver->disconnect(&dwc->gadget);
2531		spin_lock(&dwc->lock);
2532	}
2533}
2534
2535static void dwc3_suspend_gadget(struct dwc3 *dwc)
2536{
2537	if (dwc->gadget_driver && dwc->gadget_driver->suspend) {
2538		spin_unlock(&dwc->lock);
2539		dwc->gadget_driver->suspend(&dwc->gadget);
2540		spin_lock(&dwc->lock);
2541	}
2542}
2543
2544static void dwc3_resume_gadget(struct dwc3 *dwc)
2545{
2546	if (dwc->gadget_driver && dwc->gadget_driver->resume) {
2547		spin_unlock(&dwc->lock);
2548		dwc->gadget_driver->resume(&dwc->gadget);
2549		spin_lock(&dwc->lock);
2550	}
2551}
2552
2553static void dwc3_reset_gadget(struct dwc3 *dwc)
2554{
2555	if (!dwc->gadget_driver)
2556		return;
2557
2558	if (dwc->gadget.speed != USB_SPEED_UNKNOWN) {
2559		spin_unlock(&dwc->lock);
2560		usb_gadget_udc_reset(&dwc->gadget, dwc->gadget_driver);
2561		spin_lock(&dwc->lock);
2562	}
2563}
2564
2565static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)
2566{
2567	struct dwc3_ep *dep;
2568	struct dwc3_gadget_ep_cmd_params params;
2569	u32 cmd;
2570	int ret;
2571
2572	dep = dwc->eps[epnum];
2573
2574	if ((dep->flags & DWC3_EP_END_TRANSFER_PENDING) ||
2575	    !dep->resource_index)
2576		return;
2577
2578	/*
2579	 * NOTICE: We are violating what the Databook says about the
2580	 * EndTransfer command. Ideally we would _always_ wait for the
2581	 * EndTransfer Command Completion IRQ, but that's causing too
2582	 * much trouble synchronizing between us and gadget driver.
2583	 *
2584	 * We have discussed this with the IP Provider and it was
2585	 * suggested to giveback all requests here, but give HW some
2586	 * extra time to synchronize with the interconnect. We're using
2587	 * an arbitrary 100us delay for that.
2588	 *
2589	 * Note also that a similar handling was tested by Synopsys
2590	 * (thanks a lot Paul) and nothing bad has come out of it.
2591	 * In short, what we're doing is:
2592	 *
2593	 * - Issue EndTransfer WITH CMDIOC bit set
2594	 * - Wait 100us
2595	 *
2596	 * As of IP version 3.10a of the DWC_usb3 IP, the controller
2597	 * supports a mode to work around the above limitation. The
2598	 * software can poll the CMDACT bit in the DEPCMD register
2599	 * after issuing a EndTransfer command. This mode is enabled
2600	 * by writing GUCTL2[14]. This polling is already done in the
2601	 * dwc3_send_gadget_ep_cmd() function so if the mode is
2602	 * enabled, the EndTransfer command will have completed upon
2603	 * returning from this function and we don't need to delay for
2604	 * 100us.
2605	 *
2606	 * This mode is NOT available on the DWC_usb31 IP.
2607	 */
2608
2609	cmd = DWC3_DEPCMD_ENDTRANSFER;
2610	cmd |= force ? DWC3_DEPCMD_HIPRI_FORCERM : 0;
2611	cmd |= DWC3_DEPCMD_CMDIOC;
2612	cmd |= DWC3_DEPCMD_PARAM(dep->resource_index);
2613	memset(&params, 0, sizeof(params));
2614	ret = dwc3_send_gadget_ep_cmd(dep, cmd, &params);
2615	WARN_ON_ONCE(ret);
2616	dep->resource_index = 0;
2617	dep->flags &= ~DWC3_EP_BUSY;
2618
2619	if (dwc3_is_usb31(dwc) || dwc->revision < DWC3_REVISION_310A) {
2620		dep->flags |= DWC3_EP_END_TRANSFER_PENDING;
2621		udelay(100);
2622	}
2623}
2624
2625static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)
2626{
2627	u32 epnum;
2628
2629	for (epnum = 1; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
2630		struct dwc3_ep *dep;
2631		int ret;
2632
2633		dep = dwc->eps[epnum];
2634		if (!dep)
2635			continue;
2636
2637		if (!(dep->flags & DWC3_EP_STALL))
2638			continue;
2639
2640		dep->flags &= ~DWC3_EP_STALL;
2641
2642		ret = dwc3_send_clear_stall_ep_cmd(dep);
2643		WARN_ON_ONCE(ret);
2644	}
2645}
2646
2647static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
2648{
2649	int			reg;
2650
2651	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2652	reg &= ~DWC3_DCTL_INITU1ENA;
2653	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2654
2655	reg &= ~DWC3_DCTL_INITU2ENA;
2656	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2657
2658	dwc3_disconnect_gadget(dwc);
2659
2660	dwc->gadget.speed = USB_SPEED_UNKNOWN;
2661	dwc->setup_packet_pending = false;
2662	usb_gadget_set_state(&dwc->gadget, USB_STATE_NOTATTACHED);
2663
2664	dwc->connected = false;
2665}
2666
2667static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
2668{
2669	u32			reg;
2670
2671	dwc->connected = true;
2672
2673	/*
2674	 * WORKAROUND: DWC3 revisions <1.88a have an issue which
2675	 * would cause a missing Disconnect Event if there's a
2676	 * pending Setup Packet in the FIFO.
2677	 *
2678	 * There's no suggested workaround on the official Bug
2679	 * report, which states that "unless the driver/application
2680	 * is doing any special handling of a disconnect event,
2681	 * there is no functional issue".
2682	 *
2683	 * Unfortunately, it turns out that we _do_ some special
2684	 * handling of a disconnect event, namely complete all
2685	 * pending transfers, notify gadget driver of the
2686	 * disconnection, and so on.
2687	 *
2688	 * Our suggested workaround is to follow the Disconnect
2689	 * Event steps here, instead, based on a setup_packet_pending
2690	 * flag. Such flag gets set whenever we have a SETUP_PENDING
2691	 * status for EP0 TRBs and gets cleared on XferComplete for the
2692	 * same endpoint.
2693	 *
2694	 * Refers to:
2695	 *
2696	 * STAR#9000466709: RTL: Device : Disconnect event not
2697	 * generated if setup packet pending in FIFO
2698	 */
2699	if (dwc->revision < DWC3_REVISION_188A) {
2700		if (dwc->setup_packet_pending)
2701			dwc3_gadget_disconnect_interrupt(dwc);
2702	}
2703
2704	dwc3_reset_gadget(dwc);
2705
2706	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2707	reg &= ~DWC3_DCTL_TSTCTRL_MASK;
2708	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2709	dwc->test_mode = false;
2710	dwc3_clear_stall_all_ep(dwc);
2711
2712	/* Reset device address to zero */
2713	reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2714	reg &= ~(DWC3_DCFG_DEVADDR_MASK);
2715	dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2716}
2717
2718static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
2719{
2720	struct dwc3_ep		*dep;
2721	int			ret;
2722	u32			reg;
2723	u8			speed;
2724
2725	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
2726	speed = reg & DWC3_DSTS_CONNECTSPD;
2727	dwc->speed = speed;
2728
2729	/*
2730	 * RAMClkSel is reset to 0 after USB reset, so it must be reprogrammed
2731	 * each time on Connect Done.
2732	 *
2733	 * Currently we always use the reset value. If any platform
2734	 * wants to set this to a different value, we need to add a
2735	 * setting and update GCTL.RAMCLKSEL here.
2736	 */
2737
2738	switch (speed) {
2739	case DWC3_DSTS_SUPERSPEED_PLUS:
2740		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
2741		dwc->gadget.ep0->maxpacket = 512;
2742		dwc->gadget.speed = USB_SPEED_SUPER_PLUS;
2743		break;
2744	case DWC3_DSTS_SUPERSPEED:
2745		/*
2746		 * WORKAROUND: DWC3 revisions <1.90a have an issue which
2747		 * would cause a missing USB3 Reset event.
2748		 *
2749		 * In such situations, we should force a USB3 Reset
2750		 * event by calling our dwc3_gadget_reset_interrupt()
2751		 * routine.
2752		 *
2753		 * Refers to:
2754		 *
2755		 * STAR#9000483510: RTL: SS : USB3 reset event may
2756		 * not be generated always when the link enters poll
2757		 */
2758		if (dwc->revision < DWC3_REVISION_190A)
2759			dwc3_gadget_reset_interrupt(dwc);
2760
2761		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
2762		dwc->gadget.ep0->maxpacket = 512;
2763		dwc->gadget.speed = USB_SPEED_SUPER;
2764		break;
2765	case DWC3_DSTS_HIGHSPEED:
2766		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2767		dwc->gadget.ep0->maxpacket = 64;
2768		dwc->gadget.speed = USB_SPEED_HIGH;
2769		break;
2770	case DWC3_DSTS_FULLSPEED:
2771		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(64);
2772		dwc->gadget.ep0->maxpacket = 64;
2773		dwc->gadget.speed = USB_SPEED_FULL;
2774		break;
2775	case DWC3_DSTS_LOWSPEED:
2776		dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(8);
2777		dwc->gadget.ep0->maxpacket = 8;
2778		dwc->gadget.speed = USB_SPEED_LOW;
2779		break;
2780	}
2781
2782	dwc->eps[1]->endpoint.maxpacket = dwc->gadget.ep0->maxpacket;
2783
2784	/* Enable USB2 LPM Capability */
2785
2786	if ((dwc->revision > DWC3_REVISION_194A) &&
2787	    (speed != DWC3_DSTS_SUPERSPEED) &&
2788	    (speed != DWC3_DSTS_SUPERSPEED_PLUS)) {
2789		reg = dwc3_readl(dwc->regs, DWC3_DCFG);
2790		reg |= DWC3_DCFG_LPM_CAP;
2791		dwc3_writel(dwc->regs, DWC3_DCFG, reg);
2792
2793		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2794		reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
2795
2796		reg |= DWC3_DCTL_HIRD_THRES(dwc->hird_threshold);
2797
2798		/*
2799		 * When dwc3 revisions >= 2.40a, LPM Erratum is enabled and
2800		 * DCFG.LPMCap is set, core responses with an ACK and the
2801		 * BESL value in the LPM token is less than or equal to LPM
2802		 * NYET threshold.
2803		 */
2804		WARN_ONCE(dwc->revision < DWC3_REVISION_240A
2805				&& dwc->has_lpm_erratum,
2806				"LPM Erratum not available on dwc3 revisions < 2.40a\n");
2807
2808		if (dwc->has_lpm_erratum && dwc->revision >= DWC3_REVISION_240A)
2809			reg |= DWC3_DCTL_LPM_ERRATA(dwc->lpm_nyet_threshold);
2810
2811		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2812	} else {
2813		reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2814		reg &= ~DWC3_DCTL_HIRD_THRES_MASK;
2815		dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2816	}
2817
2818	dep = dwc->eps[0];
2819	ret = __dwc3_gadget_ep_enable(dep, true, false);
2820	if (ret) {
2821		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2822		return;
2823	}
2824
2825	dep = dwc->eps[1];
2826	ret = __dwc3_gadget_ep_enable(dep, true, false);
2827	if (ret) {
2828		dev_err(dwc->dev, "failed to enable %s\n", dep->name);
2829		return;
2830	}
2831
2832	/*
2833	 * Configure PHY via GUSB3PIPECTLn if required.
2834	 *
2835	 * Update GTXFIFOSIZn
2836	 *
2837	 * In both cases reset values should be sufficient.
2838	 */
2839}
2840
2841static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
2842{
2843	/*
2844	 * TODO take core out of low power mode when that's
2845	 * implemented.
2846	 */
2847
2848	if (dwc->gadget_driver && dwc->gadget_driver->resume) {
2849		spin_unlock(&dwc->lock);
2850		dwc->gadget_driver->resume(&dwc->gadget);
2851		spin_lock(&dwc->lock);
2852	}
2853}
2854
2855static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
2856		unsigned int evtinfo)
2857{
2858	enum dwc3_link_state	next = evtinfo & DWC3_LINK_STATE_MASK;
2859	unsigned int		pwropt;
2860
2861	/*
2862	 * WORKAROUND: DWC3 < 2.50a have an issue when configured without
2863	 * Hibernation mode enabled which would show up when device detects
2864	 * host-initiated U3 exit.
2865	 *
2866	 * In that case, device will generate a Link State Change Interrupt
2867	 * from U3 to RESUME which is only necessary if Hibernation is
2868	 * configured in.
2869	 *
2870	 * There are no functional changes due to such spurious event and we
2871	 * just need to ignore it.
2872	 *
2873	 * Refers to:
2874	 *
2875	 * STAR#9000570034 RTL: SS Resume event generated in non-Hibernation
2876	 * operational mode
2877	 */
2878	pwropt = DWC3_GHWPARAMS1_EN_PWROPT(dwc->hwparams.hwparams1);
2879	if ((dwc->revision < DWC3_REVISION_250A) &&
2880			(pwropt != DWC3_GHWPARAMS1_EN_PWROPT_HIB)) {
2881		if ((dwc->link_state == DWC3_LINK_STATE_U3) &&
2882				(next == DWC3_LINK_STATE_RESUME)) {
2883			return;
2884		}
2885	}
2886
2887	/*
2888	 * WORKAROUND: DWC3 Revisions <1.83a have an issue which, depending
2889	 * on the link partner, the USB session might do multiple entry/exit
2890	 * of low power states before a transfer takes place.
2891	 *
2892	 * Due to this problem, we might experience lower throughput. The
2893	 * suggested workaround is to disable DCTL[12:9] bits if we're
2894	 * transitioning from U1/U2 to U0 and enable those bits again
2895	 * after a transfer completes and there are no pending transfers
2896	 * on any of the enabled endpoints.
2897	 *
2898	 * This is the first half of that workaround.
2899	 *
2900	 * Refers to:
2901	 *
2902	 * STAR#9000446952: RTL: Device SS : if U1/U2 ->U0 takes >128us
2903	 * core send LGO_Ux entering U0
2904	 */
2905	if (dwc->revision < DWC3_REVISION_183A) {
2906		if (next == DWC3_LINK_STATE_U0) {
2907			u32	u1u2;
2908			u32	reg;
2909
2910			switch (dwc->link_state) {
2911			case DWC3_LINK_STATE_U1:
2912			case DWC3_LINK_STATE_U2:
2913				reg = dwc3_readl(dwc->regs, DWC3_DCTL);
2914				u1u2 = reg & (DWC3_DCTL_INITU2ENA
2915						| DWC3_DCTL_ACCEPTU2ENA
2916						| DWC3_DCTL_INITU1ENA
2917						| DWC3_DCTL_ACCEPTU1ENA);
2918
2919				if (!dwc->u1u2)
2920					dwc->u1u2 = reg & u1u2;
2921
2922				reg &= ~u1u2;
2923
2924				dwc3_writel(dwc->regs, DWC3_DCTL, reg);
2925				break;
2926			default:
2927				/* do nothing */
2928				break;
2929			}
2930		}
2931	}
2932
2933	switch (next) {
2934	case DWC3_LINK_STATE_U1:
2935		if (dwc->speed == USB_SPEED_SUPER)
2936			dwc3_suspend_gadget(dwc);
2937		break;
2938	case DWC3_LINK_STATE_U2:
2939	case DWC3_LINK_STATE_U3:
2940		dwc3_suspend_gadget(dwc);
2941		break;
2942	case DWC3_LINK_STATE_RESUME:
2943		dwc3_resume_gadget(dwc);
2944		break;
2945	default:
2946		/* do nothing */
2947		break;
2948	}
2949
2950	dwc->link_state = next;
2951}
2952
2953static void dwc3_gadget_suspend_interrupt(struct dwc3 *dwc,
2954					  unsigned int evtinfo)
2955{
2956	enum dwc3_link_state next = evtinfo & DWC3_LINK_STATE_MASK;
2957
2958	if (dwc->link_state != next && next == DWC3_LINK_STATE_U3)
2959		dwc3_suspend_gadget(dwc);
2960
2961	dwc->link_state = next;
2962}
2963
2964static void dwc3_gadget_hibernation_interrupt(struct dwc3 *dwc,
2965		unsigned int evtinfo)
2966{
2967	unsigned int is_ss = evtinfo & BIT(4);
2968
2969	/*
2970	 * WORKAROUND: DWC3 revison 2.20a with hibernation support
2971	 * have a known issue which can cause USB CV TD.9.23 to fail
2972	 * randomly.
2973	 *
2974	 * Because of this issue, core could generate bogus hibernation
2975	 * events which SW needs to ignore.
2976	 *
2977	 * Refers to:
2978	 *
2979	 * STAR#9000546576: Device Mode Hibernation: Issue in USB 2.0
2980	 * Device Fallback from SuperSpeed
2981	 */
2982	if (is_ss ^ (dwc->speed == USB_SPEED_SUPER))
2983		return;
2984
2985	/* enter hibernation here */
2986}
2987
2988static void dwc3_gadget_interrupt(struct dwc3 *dwc,
2989		const struct dwc3_event_devt *event)
2990{
2991	switch (event->type) {
2992	case DWC3_DEVICE_EVENT_DISCONNECT:
2993		dwc3_gadget_disconnect_interrupt(dwc);
2994		break;
2995	case DWC3_DEVICE_EVENT_RESET:
2996		dwc3_gadget_reset_interrupt(dwc);
2997		break;
2998	case DWC3_DEVICE_EVENT_CONNECT_DONE:
2999		dwc3_gadget_conndone_interrupt(dwc);
3000		break;
3001	case DWC3_DEVICE_EVENT_WAKEUP:
3002		dwc3_gadget_wakeup_interrupt(dwc);
3003		break;
3004	case DWC3_DEVICE_EVENT_HIBER_REQ:
3005		if (dev_WARN_ONCE(dwc->dev, !dwc->has_hibernation,
3006					"unexpected hibernation event\n"))
3007			break;
3008
3009		dwc3_gadget_hibernation_interrupt(dwc, event->event_info);
3010		break;
3011	case DWC3_DEVICE_EVENT_LINK_STATUS_CHANGE:
3012		dwc3_gadget_linksts_change_interrupt(dwc, event->event_info);
3013		break;
3014	case DWC3_DEVICE_EVENT_EOPF:
3015		/* It changed to be suspend event for version 2.30a and above */
3016		if (dwc->revision >= DWC3_REVISION_230A) {
3017			/*
3018			 * Ignore suspend event until the gadget enters into
3019			 * USB_STATE_CONFIGURED state.
3020			 */
3021			if (dwc->gadget.state >= USB_STATE_CONFIGURED)
3022				dwc3_gadget_suspend_interrupt(dwc,
3023						event->event_info);
3024		}
3025		break;
3026	case DWC3_DEVICE_EVENT_SOF:
3027	case DWC3_DEVICE_EVENT_ERRATIC_ERROR:
3028	case DWC3_DEVICE_EVENT_CMD_CMPL:
3029	case DWC3_DEVICE_EVENT_OVERFLOW:
3030		break;
3031	default:
3032		dev_WARN(dwc->dev, "UNKNOWN IRQ %d\n", event->type);
3033	}
3034}
3035
3036static void dwc3_process_event_entry(struct dwc3 *dwc,
3037		const union dwc3_event *event)
3038{
3039	trace_dwc3_event(event->raw, dwc);
3040
3041	if (!event->type.is_devspec)
3042		dwc3_endpoint_interrupt(dwc, &event->depevt);
3043	else if (event->type.type == DWC3_EVENT_TYPE_DEV)
3044		dwc3_gadget_interrupt(dwc, &event->devt);
3045	else
3046		dev_err(dwc->dev, "UNKNOWN IRQ type %d\n", event->raw);
3047}
3048
3049static irqreturn_t dwc3_process_event_buf(struct dwc3_event_buffer *evt)
3050{
3051	struct dwc3 *dwc = evt->dwc;
3052	irqreturn_t ret = IRQ_NONE;
3053	int left;
3054	u32 reg;
3055
3056	left = evt->count;
3057
3058	if (!(evt->flags & DWC3_EVENT_PENDING))
3059		return IRQ_NONE;
3060
3061	while (left > 0) {
3062		union dwc3_event event;
3063
3064		event.raw = *(u32 *) (evt->cache + evt->lpos);
3065
3066		dwc3_process_event_entry(dwc, &event);
3067
3068		/*
3069		 * FIXME we wrap around correctly to the next entry as
3070		 * almost all entries are 4 bytes in size. There is one
3071		 * entry which has 12 bytes which is a regular entry
3072		 * followed by 8 bytes data. ATM I don't know how
3073		 * things are organized if we get next to the a
3074		 * boundary so I worry about that once we try to handle
3075		 * that.
3076		 */
3077		evt->lpos = (evt->lpos + 4) % evt->length;
3078		left -= 4;
3079	}
3080
3081	evt->count = 0;
3082	evt->flags &= ~DWC3_EVENT_PENDING;
3083	ret = IRQ_HANDLED;
3084
3085	/* Unmask interrupt */
3086	reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
3087	reg &= ~DWC3_GEVNTSIZ_INTMASK;
3088	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
3089
3090	if (dwc->imod_interval) {
3091		dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), DWC3_GEVNTCOUNT_EHB);
3092		dwc3_writel(dwc->regs, DWC3_DEV_IMOD(0), dwc->imod_interval);
3093	}
3094
3095	return ret;
3096}
3097
3098static irqreturn_t dwc3_thread_interrupt(int irq, void *_evt)
3099{
3100	struct dwc3_event_buffer *evt = _evt;
3101	struct dwc3 *dwc = evt->dwc;
3102	unsigned long flags;
3103	irqreturn_t ret = IRQ_NONE;
3104
3105	spin_lock_irqsave(&dwc->lock, flags);
3106	ret = dwc3_process_event_buf(evt);
3107	spin_unlock_irqrestore(&dwc->lock, flags);
3108
3109	return ret;
3110}
3111
3112static irqreturn_t dwc3_check_event_buf(struct dwc3_event_buffer *evt)
3113{
3114	struct dwc3 *dwc = evt->dwc;
3115	u32 amount;
3116	u32 count;
3117	u32 reg;
3118
3119	if (pm_runtime_suspended(dwc->dev)) {
3120		pm_runtime_get(dwc->dev);
3121		disable_irq_nosync(dwc->irq_gadget);
3122		dwc->pending_events = true;
3123		return IRQ_HANDLED;
3124	}
3125
3126	/*
3127	 * With PCIe legacy interrupt, test shows that top-half irq handler can
3128	 * be called again after HW interrupt deassertion. Check if bottom-half
3129	 * irq event handler completes before caching new event to prevent
3130	 * losing events.
3131	 */
3132	if (evt->flags & DWC3_EVENT_PENDING)
3133		return IRQ_HANDLED;
3134
3135	count = dwc3_readl(dwc->regs, DWC3_GEVNTCOUNT(0));
3136	count &= DWC3_GEVNTCOUNT_MASK;
3137	if (!count)
3138		return IRQ_NONE;
3139
3140	evt->count = count;
3141	evt->flags |= DWC3_EVENT_PENDING;
3142
3143	/* Mask interrupt */
3144	reg = dwc3_readl(dwc->regs, DWC3_GEVNTSIZ(0));
3145	reg |= DWC3_GEVNTSIZ_INTMASK;
3146	dwc3_writel(dwc->regs, DWC3_GEVNTSIZ(0), reg);
3147
3148	amount = min(count, evt->length - evt->lpos);
3149	memcpy(evt->cache + evt->lpos, evt->buf + evt->lpos, amount);
3150
3151	if (amount < count)
3152		memcpy(evt->cache, evt->buf, count - amount);
3153
3154	dwc3_writel(dwc->regs, DWC3_GEVNTCOUNT(0), count);
3155
3156	return IRQ_WAKE_THREAD;
3157}
3158
3159static irqreturn_t dwc3_interrupt(int irq, void *_evt)
3160{
3161	struct dwc3_event_buffer	*evt = _evt;
3162
3163	return dwc3_check_event_buf(evt);
3164}
3165
3166static int dwc3_gadget_get_irq(struct dwc3 *dwc)
3167{
3168	struct platform_device *dwc3_pdev = to_platform_device(dwc->dev);
3169	int irq;
3170
3171	irq = platform_get_irq_byname(dwc3_pdev, "peripheral");
3172	if (irq > 0)
3173		goto out;
3174
3175	if (irq == -EPROBE_DEFER)
3176		goto out;
3177
3178	irq = platform_get_irq_byname(dwc3_pdev, "dwc_usb3");
3179	if (irq > 0)
3180		goto out;
3181
3182	if (irq == -EPROBE_DEFER)
3183		goto out;
3184
3185	irq = platform_get_irq(dwc3_pdev, 0);
3186	if (irq > 0)
3187		goto out;
3188
3189	if (irq != -EPROBE_DEFER)
3190		dev_err(dwc->dev, "missing peripheral IRQ\n");
3191
3192	if (!irq)
3193		irq = -EINVAL;
3194
3195out:
3196	return irq;
3197}
3198
3199/**
3200 * dwc3_gadget_init - initializes gadget related registers
3201 * @dwc: pointer to our controller context structure
3202 *
3203 * Returns 0 on success otherwise negative errno.
3204 */
3205int dwc3_gadget_init(struct dwc3 *dwc)
3206{
3207	int ret;
3208	int irq;
3209
3210	irq = dwc3_gadget_get_irq(dwc);
3211	if (irq < 0) {
3212		ret = irq;
3213		goto err0;
3214	}
3215
3216	dwc->irq_gadget = irq;
3217
3218	dwc->ep0_trb = dma_alloc_coherent(dwc->sysdev,
3219					  sizeof(*dwc->ep0_trb) * 2,
3220					  &dwc->ep0_trb_addr, GFP_KERNEL);
3221	if (!dwc->ep0_trb) {
3222		dev_err(dwc->dev, "failed to allocate ep0 trb\n");
3223		ret = -ENOMEM;
3224		goto err0;
3225	}
3226
3227	dwc->setup_buf = kzalloc(DWC3_EP0_SETUP_SIZE, GFP_KERNEL);
3228	if (!dwc->setup_buf) {
3229		ret = -ENOMEM;
3230		goto err1;
3231	}
3232
3233	dwc->bounce = dma_alloc_coherent(dwc->sysdev, DWC3_BOUNCE_SIZE,
3234			&dwc->bounce_addr, GFP_KERNEL);
3235	if (!dwc->bounce) {
3236		ret = -ENOMEM;
3237		goto err2;
3238	}
3239
3240	init_completion(&dwc->ep0_in_setup);
3241
3242	dwc->gadget.ops			= &dwc3_gadget_ops;
3243	dwc->gadget.speed		= USB_SPEED_UNKNOWN;
3244	dwc->gadget.sg_supported	= true;
3245	dwc->gadget.name		= "dwc3-gadget";
3246	dwc->gadget.is_otg		= dwc->dr_mode == USB_DR_MODE_OTG;
3247
3248	/*
3249	 * FIXME We might be setting max_speed to <SUPER, however versions
3250	 * <2.20a of dwc3 have an issue with metastability (documented
3251	 * elsewhere in this driver) which tells us we can't set max speed to
3252	 * anything lower than SUPER.
3253	 *
3254	 * Because gadget.max_speed is only used by composite.c and function
3255	 * drivers (i.e. it won't go into dwc3's registers) we are allowing this
3256	 * to happen so we avoid sending SuperSpeed Capability descriptor
3257	 * together with our BOS descriptor as that could confuse host into
3258	 * thinking we can handle super speed.
3259	 *
3260	 * Note that, in fact, we won't even support GetBOS requests when speed
3261	 * is less than super speed because we don't have means, yet, to tell
3262	 * composite.c that we are USB 2.0 + LPM ECN.
3263	 */
3264	if (dwc->revision < DWC3_REVISION_220A &&
3265	    !dwc->dis_metastability_quirk)
3266		dev_info(dwc->dev, "changing max_speed on rev %08x\n",
3267				dwc->revision);
3268
3269	dwc->gadget.max_speed		= dwc->maximum_speed;
3270
3271	/*
3272	 * REVISIT: Here we should clear all pending IRQs to be
3273	 * sure we're starting from a well known location.
3274	 */
3275
3276	ret = dwc3_gadget_init_endpoints(dwc, dwc->num_eps);
3277	if (ret)
3278		goto err3;
3279
3280	ret = usb_add_gadget_udc(dwc->dev, &dwc->gadget);
3281	if (ret) {
3282		dev_err(dwc->dev, "failed to register udc\n");
3283		goto err4;
3284	}
3285
3286	return 0;
3287
3288err4:
3289	dwc3_gadget_free_endpoints(dwc);
3290
3291err3:
3292	dma_free_coherent(dwc->sysdev, DWC3_BOUNCE_SIZE, dwc->bounce,
3293			dwc->bounce_addr);
3294
3295err2:
3296	kfree(dwc->setup_buf);
3297
3298err1:
3299	dma_free_coherent(dwc->sysdev, sizeof(*dwc->ep0_trb) * 2,
3300			dwc->ep0_trb, dwc->ep0_trb_addr);
3301
3302err0:
3303	return ret;
3304}
3305
3306/* -------------------------------------------------------------------------- */
3307
3308void dwc3_gadget_exit(struct dwc3 *dwc)
3309{
3310	usb_del_gadget_udc(&dwc->gadget);
3311	dwc3_gadget_free_endpoints(dwc);
3312	dma_free_coherent(dwc->sysdev, DWC3_BOUNCE_SIZE, dwc->bounce,
3313			  dwc->bounce_addr);
3314	kfree(dwc->setup_buf);
3315	dma_free_coherent(dwc->sysdev, sizeof(*dwc->ep0_trb) * 2,
3316			  dwc->ep0_trb, dwc->ep0_trb_addr);
3317}
3318
3319int dwc3_gadget_suspend(struct dwc3 *dwc)
3320{
3321	if (!dwc->gadget_driver)
3322		return 0;
3323
3324	dwc3_gadget_run_stop(dwc, false, false);
3325	dwc3_disconnect_gadget(dwc);
3326	__dwc3_gadget_stop(dwc);
3327
3328	return 0;
3329}
3330
3331int dwc3_gadget_resume(struct dwc3 *dwc)
3332{
3333	int			ret;
3334
3335	if (!dwc->gadget_driver)
3336		return 0;
3337
3338	ret = __dwc3_gadget_start(dwc);
3339	if (ret < 0)
3340		goto err0;
3341
3342	ret = dwc3_gadget_run_stop(dwc, true, false);
3343	if (ret < 0)
3344		goto err1;
3345
3346	return 0;
3347
3348err1:
3349	__dwc3_gadget_stop(dwc);
3350
3351err0:
3352	return ret;
3353}
3354
3355void dwc3_gadget_process_pending_events(struct dwc3 *dwc)
3356{
3357	if (dwc->pending_events) {
3358		dwc3_interrupt(dwc->irq_gadget, dwc->ev_buf);
3359		dwc->pending_events = false;
3360		enable_irq(dwc->irq_gadget);
3361	}
3362}