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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Driver for the NXP ISP1761 device controller
   4 *
   5 * Copyright 2021 Linaro, Rui Miguel Silva
   6 * Copyright 2014 Ideas on Board Oy
   7 *
   8 * Contacts:
   9 *	Laurent Pinchart <laurent.pinchart@ideasonboard.com>
  10 *	Rui Miguel Silva <rui.silva@linaro.org>
  11 */
  12
  13#include <linux/interrupt.h>
  14#include <linux/io.h>
  15#include <linux/kernel.h>
  16#include <linux/list.h>
  17#include <linux/module.h>
  18#include <linux/slab.h>
  19#include <linux/timer.h>
  20#include <linux/usb.h>
  21
  22#include "isp1760-core.h"
  23#include "isp1760-regs.h"
  24#include "isp1760-udc.h"
  25
  26#define ISP1760_VBUS_POLL_INTERVAL	msecs_to_jiffies(500)
  27
  28struct isp1760_request {
  29	struct usb_request req;
  30	struct list_head queue;
  31	struct isp1760_ep *ep;
  32	unsigned int packet_size;
  33};
  34
  35static inline struct isp1760_udc *gadget_to_udc(struct usb_gadget *gadget)
  36{
  37	return container_of(gadget, struct isp1760_udc, gadget);
  38}
  39
  40static inline struct isp1760_ep *ep_to_udc_ep(struct usb_ep *ep)
  41{
  42	return container_of(ep, struct isp1760_ep, ep);
  43}
  44
  45static inline struct isp1760_request *req_to_udc_req(struct usb_request *req)
  46{
  47	return container_of(req, struct isp1760_request, req);
  48}
  49
  50static u32 isp1760_udc_read(struct isp1760_udc *udc, u16 field)
  51{
  52	return isp1760_field_read(udc->fields, field);
  53}
  54
  55static void isp1760_udc_write(struct isp1760_udc *udc, u16 field, u32 val)
  56{
  57	isp1760_field_write(udc->fields, field, val);
  58}
  59
  60static u32 isp1760_udc_read_raw(struct isp1760_udc *udc, u16 reg)
  61{
  62	__le32 val;
  63
  64	regmap_raw_read(udc->regs, reg, &val, 4);
  65
  66	return le32_to_cpu(val);
  67}
  68
  69static u16 isp1760_udc_read_raw16(struct isp1760_udc *udc, u16 reg)
  70{
  71	__le16 val;
  72
  73	regmap_raw_read(udc->regs, reg, &val, 2);
  74
  75	return le16_to_cpu(val);
  76}
  77
  78static void isp1760_udc_write_raw(struct isp1760_udc *udc, u16 reg, u32 val)
  79{
  80	__le32 val_le = cpu_to_le32(val);
  81
  82	regmap_raw_write(udc->regs, reg, &val_le, 4);
  83}
  84
  85static void isp1760_udc_write_raw16(struct isp1760_udc *udc, u16 reg, u16 val)
  86{
  87	__le16 val_le = cpu_to_le16(val);
  88
  89	regmap_raw_write(udc->regs, reg, &val_le, 2);
  90}
  91
  92static void isp1760_udc_set(struct isp1760_udc *udc, u32 field)
  93{
  94	isp1760_udc_write(udc, field, 0xFFFFFFFF);
  95}
  96
  97static void isp1760_udc_clear(struct isp1760_udc *udc, u32 field)
  98{
  99	isp1760_udc_write(udc, field, 0);
 100}
 101
 102static bool isp1760_udc_is_set(struct isp1760_udc *udc, u32 field)
 103{
 104	return !!isp1760_udc_read(udc, field);
 105}
 106/* -----------------------------------------------------------------------------
 107 * Endpoint Management
 108 */
 109
 110static struct isp1760_ep *isp1760_udc_find_ep(struct isp1760_udc *udc,
 111					      u16 index)
 112{
 113	unsigned int i;
 114
 115	if (index == 0)
 116		return &udc->ep[0];
 117
 118	for (i = 1; i < ARRAY_SIZE(udc->ep); ++i) {
 119		if (udc->ep[i].addr == index)
 120			return udc->ep[i].desc ? &udc->ep[i] : NULL;
 121	}
 122
 123	return NULL;
 124}
 125
 126static void __isp1760_udc_select_ep(struct isp1760_udc *udc,
 127				    struct isp1760_ep *ep, int dir)
 128{
 129	isp1760_udc_write(udc, DC_ENDPIDX, ep->addr & USB_ENDPOINT_NUMBER_MASK);
 130
 131	if (dir == USB_DIR_IN)
 132		isp1760_udc_set(udc, DC_EPDIR);
 133	else
 134		isp1760_udc_clear(udc, DC_EPDIR);
 135}
 136
 137/**
 138 * isp1760_udc_select_ep - Select an endpoint for register access
 139 * @ep: The endpoint
 140 * @udc: Reference to the device controller
 141 *
 142 * The ISP1761 endpoint registers are banked. This function selects the target
 143 * endpoint for banked register access. The selection remains valid until the
 144 * next call to this function, the next direct access to the EPINDEX register
 145 * or the next reset, whichever comes first.
 146 *
 147 * Called with the UDC spinlock held.
 148 */
 149static void isp1760_udc_select_ep(struct isp1760_udc *udc,
 150				  struct isp1760_ep *ep)
 151{
 152	__isp1760_udc_select_ep(udc, ep, ep->addr & USB_ENDPOINT_DIR_MASK);
 153}
 154
 155/* Called with the UDC spinlock held. */
 156static void isp1760_udc_ctrl_send_status(struct isp1760_ep *ep, int dir)
 157{
 158	struct isp1760_udc *udc = ep->udc;
 159
 160	/*
 161	 * Proceed to the status stage. The status stage data packet flows in
 162	 * the direction opposite to the data stage data packets, we thus need
 163	 * to select the OUT/IN endpoint for IN/OUT transfers.
 164	 */
 165	if (dir == USB_DIR_IN)
 166		isp1760_udc_clear(udc, DC_EPDIR);
 167	else
 168		isp1760_udc_set(udc, DC_EPDIR);
 169
 170	isp1760_udc_write(udc, DC_ENDPIDX, 1);
 171	isp1760_udc_set(udc, DC_STATUS);
 172
 173	/*
 174	 * The hardware will terminate the request automatically and go back to
 175	 * the setup stage without notifying us.
 176	 */
 177	udc->ep0_state = ISP1760_CTRL_SETUP;
 178}
 179
 180/* Called without the UDC spinlock held. */
 181static void isp1760_udc_request_complete(struct isp1760_ep *ep,
 182					 struct isp1760_request *req,
 183					 int status)
 184{
 185	struct isp1760_udc *udc = ep->udc;
 186	unsigned long flags;
 187
 188	dev_dbg(ep->udc->isp->dev, "completing request %p with status %d\n",
 189		req, status);
 190
 191	req->ep = NULL;
 192	req->req.status = status;
 193	req->req.complete(&ep->ep, &req->req);
 194
 195	spin_lock_irqsave(&udc->lock, flags);
 196
 197	/*
 198	 * When completing control OUT requests, move to the status stage after
 199	 * calling the request complete callback. This gives the gadget an
 200	 * opportunity to stall the control transfer if needed.
 201	 */
 202	if (status == 0 && ep->addr == 0 && udc->ep0_dir == USB_DIR_OUT)
 203		isp1760_udc_ctrl_send_status(ep, USB_DIR_OUT);
 204
 205	spin_unlock_irqrestore(&udc->lock, flags);
 206}
 207
 208static void isp1760_udc_ctrl_send_stall(struct isp1760_ep *ep)
 209{
 210	struct isp1760_udc *udc = ep->udc;
 211	unsigned long flags;
 212
 213	dev_dbg(ep->udc->isp->dev, "%s(ep%02x)\n", __func__, ep->addr);
 214
 215	spin_lock_irqsave(&udc->lock, flags);
 216
 217	/* Stall both the IN and OUT endpoints. */
 218	__isp1760_udc_select_ep(udc, ep, USB_DIR_OUT);
 219	isp1760_udc_set(udc, DC_STALL);
 220	__isp1760_udc_select_ep(udc, ep, USB_DIR_IN);
 221	isp1760_udc_set(udc, DC_STALL);
 222
 223	/* A protocol stall completes the control transaction. */
 224	udc->ep0_state = ISP1760_CTRL_SETUP;
 225
 226	spin_unlock_irqrestore(&udc->lock, flags);
 227}
 228
 229/* -----------------------------------------------------------------------------
 230 * Data Endpoints
 231 */
 232
 233/* Called with the UDC spinlock held. */
 234static bool isp1760_udc_receive(struct isp1760_ep *ep,
 235				struct isp1760_request *req)
 236{
 237	struct isp1760_udc *udc = ep->udc;
 238	unsigned int len;
 239	u32 *buf;
 240	int i;
 241
 242	isp1760_udc_select_ep(udc, ep);
 243	len = isp1760_udc_read(udc, DC_BUFLEN);
 244
 245	dev_dbg(udc->isp->dev, "%s: received %u bytes (%u/%u done)\n",
 246		__func__, len, req->req.actual, req->req.length);
 247
 248	len = min(len, req->req.length - req->req.actual);
 249
 250	if (!len) {
 251		/*
 252		 * There's no data to be read from the FIFO, acknowledge the RX
 253		 * interrupt by clearing the buffer.
 254		 *
 255		 * TODO: What if another packet arrives in the meantime ? The
 256		 * datasheet doesn't clearly document how this should be
 257		 * handled.
 258		 */
 259		isp1760_udc_set(udc, DC_CLBUF);
 260		return false;
 261	}
 262
 263	buf = req->req.buf + req->req.actual;
 264
 265	/*
 266	 * Make sure not to read more than one extra byte, otherwise data from
 267	 * the next packet might be removed from the FIFO.
 268	 */
 269	for (i = len; i > 2; i -= 4, ++buf)
 270		*buf = isp1760_udc_read_raw(udc, ISP176x_DC_DATAPORT);
 271	if (i > 0)
 272		*(u16 *)buf = isp1760_udc_read_raw16(udc, ISP176x_DC_DATAPORT);
 273
 274	req->req.actual += len;
 275
 276	/*
 277	 * TODO: The short_not_ok flag isn't supported yet, but isn't used by
 278	 * any gadget driver either.
 279	 */
 280
 281	dev_dbg(udc->isp->dev,
 282		"%s: req %p actual/length %u/%u maxpacket %u packet size %u\n",
 283		__func__, req, req->req.actual, req->req.length, ep->maxpacket,
 284		len);
 285
 286	ep->rx_pending = false;
 287
 288	/*
 289	 * Complete the request if all data has been received or if a short
 290	 * packet has been received.
 291	 */
 292	if (req->req.actual == req->req.length || len < ep->maxpacket) {
 293		list_del(&req->queue);
 294		return true;
 295	}
 296
 297	return false;
 298}
 299
 300static void isp1760_udc_transmit(struct isp1760_ep *ep,
 301				 struct isp1760_request *req)
 302{
 303	struct isp1760_udc *udc = ep->udc;
 304	u32 *buf = req->req.buf + req->req.actual;
 305	int i;
 306
 307	req->packet_size = min(req->req.length - req->req.actual,
 308			       ep->maxpacket);
 309
 310	dev_dbg(udc->isp->dev, "%s: transferring %u bytes (%u/%u done)\n",
 311		__func__, req->packet_size, req->req.actual,
 312		req->req.length);
 313
 314	__isp1760_udc_select_ep(udc, ep, USB_DIR_IN);
 315
 316	if (req->packet_size)
 317		isp1760_udc_write(udc, DC_BUFLEN, req->packet_size);
 318
 319	/*
 320	 * Make sure not to write more than one extra byte, otherwise extra data
 321	 * will stay in the FIFO and will be transmitted during the next control
 322	 * request. The endpoint control CLBUF bit is supposed to allow flushing
 323	 * the FIFO for this kind of conditions, but doesn't seem to work.
 324	 */
 325	for (i = req->packet_size; i > 2; i -= 4, ++buf)
 326		isp1760_udc_write_raw(udc, ISP176x_DC_DATAPORT, *buf);
 327	if (i > 0)
 328		isp1760_udc_write_raw16(udc, ISP176x_DC_DATAPORT, *(u16 *)buf);
 329
 330	if (ep->addr == 0)
 331		isp1760_udc_set(udc, DC_DSEN);
 332	if (!req->packet_size)
 333		isp1760_udc_set(udc, DC_VENDP);
 334}
 335
 336static void isp1760_ep_rx_ready(struct isp1760_ep *ep)
 337{
 338	struct isp1760_udc *udc = ep->udc;
 339	struct isp1760_request *req;
 340	bool complete;
 341
 342	spin_lock(&udc->lock);
 343
 344	if (ep->addr == 0 && udc->ep0_state != ISP1760_CTRL_DATA_OUT) {
 345		spin_unlock(&udc->lock);
 346		dev_dbg(udc->isp->dev, "%s: invalid ep0 state %u\n", __func__,
 347			udc->ep0_state);
 348		return;
 349	}
 350
 351	if (ep->addr != 0 && !ep->desc) {
 352		spin_unlock(&udc->lock);
 353		dev_dbg(udc->isp->dev, "%s: ep%02x is disabled\n", __func__,
 354			ep->addr);
 355		return;
 356	}
 357
 358	if (list_empty(&ep->queue)) {
 359		ep->rx_pending = true;
 360		spin_unlock(&udc->lock);
 361		dev_dbg(udc->isp->dev, "%s: ep%02x (%p) has no request queued\n",
 362			__func__, ep->addr, ep);
 363		return;
 364	}
 365
 366	req = list_first_entry(&ep->queue, struct isp1760_request,
 367			       queue);
 368	complete = isp1760_udc_receive(ep, req);
 369
 370	spin_unlock(&udc->lock);
 371
 372	if (complete)
 373		isp1760_udc_request_complete(ep, req, 0);
 374}
 375
 376static void isp1760_ep_tx_complete(struct isp1760_ep *ep)
 377{
 378	struct isp1760_udc *udc = ep->udc;
 379	struct isp1760_request *complete = NULL;
 380	struct isp1760_request *req;
 381	bool need_zlp;
 382
 383	spin_lock(&udc->lock);
 384
 385	if (ep->addr == 0 && udc->ep0_state != ISP1760_CTRL_DATA_IN) {
 386		spin_unlock(&udc->lock);
 387		dev_dbg(udc->isp->dev, "TX IRQ: invalid endpoint state %u\n",
 388			udc->ep0_state);
 389		return;
 390	}
 391
 392	if (list_empty(&ep->queue)) {
 393		/*
 394		 * This can happen for the control endpoint when the reply to
 395		 * the GET_STATUS IN control request is sent directly by the
 396		 * setup IRQ handler. Just proceed to the status stage.
 397		 */
 398		if (ep->addr == 0) {
 399			isp1760_udc_ctrl_send_status(ep, USB_DIR_IN);
 400			spin_unlock(&udc->lock);
 401			return;
 402		}
 403
 404		spin_unlock(&udc->lock);
 405		dev_dbg(udc->isp->dev, "%s: ep%02x has no request queued\n",
 406			__func__, ep->addr);
 407		return;
 408	}
 409
 410	req = list_first_entry(&ep->queue, struct isp1760_request,
 411			       queue);
 412	req->req.actual += req->packet_size;
 413
 414	need_zlp = req->req.actual == req->req.length &&
 415		   !(req->req.length % ep->maxpacket) &&
 416		   req->packet_size && req->req.zero;
 417
 418	dev_dbg(udc->isp->dev,
 419		"TX IRQ: req %p actual/length %u/%u maxpacket %u packet size %u zero %u need zlp %u\n",
 420		 req, req->req.actual, req->req.length, ep->maxpacket,
 421		 req->packet_size, req->req.zero, need_zlp);
 422
 423	/*
 424	 * Complete the request if all data has been sent and we don't need to
 425	 * transmit a zero length packet.
 426	 */
 427	if (req->req.actual == req->req.length && !need_zlp) {
 428		complete = req;
 429		list_del(&req->queue);
 430
 431		if (ep->addr == 0)
 432			isp1760_udc_ctrl_send_status(ep, USB_DIR_IN);
 433
 434		if (!list_empty(&ep->queue))
 435			req = list_first_entry(&ep->queue,
 436					       struct isp1760_request, queue);
 437		else
 438			req = NULL;
 439	}
 440
 441	/*
 442	 * Transmit the next packet or start the next request, if any.
 443	 *
 444	 * TODO: If the endpoint is stalled the next request shouldn't be
 445	 * started, but what about the next packet ?
 446	 */
 447	if (req)
 448		isp1760_udc_transmit(ep, req);
 449
 450	spin_unlock(&udc->lock);
 451
 452	if (complete)
 453		isp1760_udc_request_complete(ep, complete, 0);
 454}
 455
 456static int __isp1760_udc_set_halt(struct isp1760_ep *ep, bool halt)
 457{
 458	struct isp1760_udc *udc = ep->udc;
 459
 460	dev_dbg(udc->isp->dev, "%s: %s halt on ep%02x\n", __func__,
 461		halt ? "set" : "clear", ep->addr);
 462
 463	if (ep->desc && usb_endpoint_xfer_isoc(ep->desc)) {
 464		dev_dbg(udc->isp->dev, "%s: ep%02x is isochronous\n", __func__,
 465			ep->addr);
 466		return -EINVAL;
 467	}
 468
 469	isp1760_udc_select_ep(udc, ep);
 470
 471	if (halt)
 472		isp1760_udc_set(udc, DC_STALL);
 473	else
 474		isp1760_udc_clear(udc, DC_STALL);
 475
 476	if (ep->addr == 0) {
 477		/* When halting the control endpoint, stall both IN and OUT. */
 478		__isp1760_udc_select_ep(udc, ep, USB_DIR_IN);
 479		if (halt)
 480			isp1760_udc_set(udc, DC_STALL);
 481		else
 482			isp1760_udc_clear(udc, DC_STALL);
 483	} else if (!halt) {
 484		/* Reset the data PID by cycling the endpoint enable bit. */
 485		isp1760_udc_clear(udc, DC_EPENABLE);
 486		isp1760_udc_set(udc, DC_EPENABLE);
 487
 488		/*
 489		 * Disabling the endpoint emptied the transmit FIFO, fill it
 490		 * again if a request is pending.
 491		 *
 492		 * TODO: Does the gadget framework require synchronizatino with
 493		 * the TX IRQ handler ?
 494		 */
 495		if ((ep->addr & USB_DIR_IN) && !list_empty(&ep->queue)) {
 496			struct isp1760_request *req;
 497
 498			req = list_first_entry(&ep->queue,
 499					       struct isp1760_request, queue);
 500			isp1760_udc_transmit(ep, req);
 501		}
 502	}
 503
 504	ep->halted = halt;
 505
 506	return 0;
 507}
 508
 509/* -----------------------------------------------------------------------------
 510 * Control Endpoint
 511 */
 512
 513static int isp1760_udc_get_status(struct isp1760_udc *udc,
 514				  const struct usb_ctrlrequest *req)
 515{
 516	struct isp1760_ep *ep;
 517	u16 status;
 518
 519	if (req->wLength != cpu_to_le16(2) || req->wValue != cpu_to_le16(0))
 520		return -EINVAL;
 521
 522	switch (req->bRequestType) {
 523	case USB_DIR_IN | USB_RECIP_DEVICE:
 524		status = udc->devstatus;
 525		break;
 526
 527	case USB_DIR_IN | USB_RECIP_INTERFACE:
 528		status = 0;
 529		break;
 530
 531	case USB_DIR_IN | USB_RECIP_ENDPOINT:
 532		ep = isp1760_udc_find_ep(udc, le16_to_cpu(req->wIndex));
 533		if (!ep)
 534			return -EINVAL;
 535
 536		status = 0;
 537		if (ep->halted)
 538			status |= 1 << USB_ENDPOINT_HALT;
 539		break;
 540
 541	default:
 542		return -EINVAL;
 543	}
 544
 545	isp1760_udc_set(udc, DC_EPDIR);
 546	isp1760_udc_write(udc, DC_ENDPIDX, 1);
 547
 548	isp1760_udc_write(udc, DC_BUFLEN, 2);
 549
 550	isp1760_udc_write_raw16(udc, ISP176x_DC_DATAPORT, status);
 551
 552	isp1760_udc_set(udc, DC_DSEN);
 553
 554	dev_dbg(udc->isp->dev, "%s: status 0x%04x\n", __func__, status);
 555
 556	return 0;
 557}
 558
 559static int isp1760_udc_set_address(struct isp1760_udc *udc, u16 addr)
 560{
 561	if (addr > 127) {
 562		dev_dbg(udc->isp->dev, "invalid device address %u\n", addr);
 563		return -EINVAL;
 564	}
 565
 566	if (udc->gadget.state != USB_STATE_DEFAULT &&
 567	    udc->gadget.state != USB_STATE_ADDRESS) {
 568		dev_dbg(udc->isp->dev, "can't set address in state %u\n",
 569			udc->gadget.state);
 570		return -EINVAL;
 571	}
 572
 573	usb_gadget_set_state(&udc->gadget, addr ? USB_STATE_ADDRESS :
 574			     USB_STATE_DEFAULT);
 575
 576	isp1760_udc_write(udc, DC_DEVADDR, addr);
 577	isp1760_udc_set(udc, DC_DEVEN);
 578
 579	spin_lock(&udc->lock);
 580	isp1760_udc_ctrl_send_status(&udc->ep[0], USB_DIR_OUT);
 581	spin_unlock(&udc->lock);
 582
 583	return 0;
 584}
 585
 586static bool isp1760_ep0_setup_standard(struct isp1760_udc *udc,
 587				       struct usb_ctrlrequest *req)
 588{
 589	bool stall;
 590
 591	switch (req->bRequest) {
 592	case USB_REQ_GET_STATUS:
 593		return isp1760_udc_get_status(udc, req);
 594
 595	case USB_REQ_CLEAR_FEATURE:
 596		switch (req->bRequestType) {
 597		case USB_DIR_OUT | USB_RECIP_DEVICE: {
 598			/* TODO: Handle remote wakeup feature. */
 599			return true;
 600		}
 601
 602		case USB_DIR_OUT | USB_RECIP_ENDPOINT: {
 603			u16 index = le16_to_cpu(req->wIndex);
 604			struct isp1760_ep *ep;
 605
 606			if (req->wLength != cpu_to_le16(0) ||
 607			    req->wValue != cpu_to_le16(USB_ENDPOINT_HALT))
 608				return true;
 609
 610			ep = isp1760_udc_find_ep(udc, index);
 611			if (!ep)
 612				return true;
 613
 614			spin_lock(&udc->lock);
 615
 616			/*
 617			 * If the endpoint is wedged only the gadget can clear
 618			 * the halt feature. Pretend success in that case, but
 619			 * keep the endpoint halted.
 620			 */
 621			if (!ep->wedged)
 622				stall = __isp1760_udc_set_halt(ep, false);
 623			else
 624				stall = false;
 625
 626			if (!stall)
 627				isp1760_udc_ctrl_send_status(&udc->ep[0],
 628							     USB_DIR_OUT);
 629
 630			spin_unlock(&udc->lock);
 631			return stall;
 632		}
 633
 634		default:
 635			return true;
 636		}
 637		break;
 638
 639	case USB_REQ_SET_FEATURE:
 640		switch (req->bRequestType) {
 641		case USB_DIR_OUT | USB_RECIP_DEVICE: {
 642			/* TODO: Handle remote wakeup and test mode features */
 643			return true;
 644		}
 645
 646		case USB_DIR_OUT | USB_RECIP_ENDPOINT: {
 647			u16 index = le16_to_cpu(req->wIndex);
 648			struct isp1760_ep *ep;
 649
 650			if (req->wLength != cpu_to_le16(0) ||
 651			    req->wValue != cpu_to_le16(USB_ENDPOINT_HALT))
 652				return true;
 653
 654			ep = isp1760_udc_find_ep(udc, index);
 655			if (!ep)
 656				return true;
 657
 658			spin_lock(&udc->lock);
 659
 660			stall = __isp1760_udc_set_halt(ep, true);
 661			if (!stall)
 662				isp1760_udc_ctrl_send_status(&udc->ep[0],
 663							     USB_DIR_OUT);
 664
 665			spin_unlock(&udc->lock);
 666			return stall;
 667		}
 668
 669		default:
 670			return true;
 671		}
 672		break;
 673
 674	case USB_REQ_SET_ADDRESS:
 675		if (req->bRequestType != (USB_DIR_OUT | USB_RECIP_DEVICE))
 676			return true;
 677
 678		return isp1760_udc_set_address(udc, le16_to_cpu(req->wValue));
 679
 680	case USB_REQ_SET_CONFIGURATION:
 681		if (req->bRequestType != (USB_DIR_OUT | USB_RECIP_DEVICE))
 682			return true;
 683
 684		if (udc->gadget.state != USB_STATE_ADDRESS &&
 685		    udc->gadget.state != USB_STATE_CONFIGURED)
 686			return true;
 687
 688		stall = udc->driver->setup(&udc->gadget, req) < 0;
 689		if (stall)
 690			return true;
 691
 692		usb_gadget_set_state(&udc->gadget, req->wValue ?
 693				     USB_STATE_CONFIGURED : USB_STATE_ADDRESS);
 694
 695		/*
 696		 * SET_CONFIGURATION (and SET_INTERFACE) must reset the halt
 697		 * feature on all endpoints. There is however no need to do so
 698		 * explicitly here as the gadget driver will disable and
 699		 * reenable endpoints, clearing the halt feature.
 700		 */
 701		return false;
 702
 703	default:
 704		return udc->driver->setup(&udc->gadget, req) < 0;
 705	}
 706}
 707
 708static void isp1760_ep0_setup(struct isp1760_udc *udc)
 709{
 710	union {
 711		struct usb_ctrlrequest r;
 712		u32 data[2];
 713	} req;
 714	unsigned int count;
 715	bool stall = false;
 716
 717	spin_lock(&udc->lock);
 718
 719	isp1760_udc_set(udc, DC_EP0SETUP);
 720
 721	count = isp1760_udc_read(udc, DC_BUFLEN);
 722	if (count != sizeof(req)) {
 723		spin_unlock(&udc->lock);
 724
 725		dev_err(udc->isp->dev, "invalid length %u for setup packet\n",
 726			count);
 727
 728		isp1760_udc_ctrl_send_stall(&udc->ep[0]);
 729		return;
 730	}
 731
 732	req.data[0] = isp1760_udc_read_raw(udc, ISP176x_DC_DATAPORT);
 733	req.data[1] = isp1760_udc_read_raw(udc, ISP176x_DC_DATAPORT);
 734
 735	if (udc->ep0_state != ISP1760_CTRL_SETUP) {
 736		spin_unlock(&udc->lock);
 737		dev_dbg(udc->isp->dev, "unexpected SETUP packet\n");
 738		return;
 739	}
 740
 741	/* Move to the data stage. */
 742	if (!req.r.wLength)
 743		udc->ep0_state = ISP1760_CTRL_STATUS;
 744	else if (req.r.bRequestType & USB_DIR_IN)
 745		udc->ep0_state = ISP1760_CTRL_DATA_IN;
 746	else
 747		udc->ep0_state = ISP1760_CTRL_DATA_OUT;
 748
 749	udc->ep0_dir = req.r.bRequestType & USB_DIR_IN;
 750	udc->ep0_length = le16_to_cpu(req.r.wLength);
 751
 752	spin_unlock(&udc->lock);
 753
 754	dev_dbg(udc->isp->dev,
 755		"%s: bRequestType 0x%02x bRequest 0x%02x wValue 0x%04x wIndex 0x%04x wLength 0x%04x\n",
 756		__func__, req.r.bRequestType, req.r.bRequest,
 757		le16_to_cpu(req.r.wValue), le16_to_cpu(req.r.wIndex),
 758		le16_to_cpu(req.r.wLength));
 759
 760	if ((req.r.bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD)
 761		stall = isp1760_ep0_setup_standard(udc, &req.r);
 762	else
 763		stall = udc->driver->setup(&udc->gadget, &req.r) < 0;
 764
 765	if (stall)
 766		isp1760_udc_ctrl_send_stall(&udc->ep[0]);
 767}
 768
 769/* -----------------------------------------------------------------------------
 770 * Gadget Endpoint Operations
 771 */
 772
 773static int isp1760_ep_enable(struct usb_ep *ep,
 774			     const struct usb_endpoint_descriptor *desc)
 775{
 776	struct isp1760_ep *uep = ep_to_udc_ep(ep);
 777	struct isp1760_udc *udc = uep->udc;
 778	unsigned long flags;
 779	unsigned int type;
 780
 781	dev_dbg(uep->udc->isp->dev, "%s\n", __func__);
 782
 783	/*
 784	 * Validate the descriptor. The control endpoint can't be enabled
 785	 * manually.
 786	 */
 787	if (desc->bDescriptorType != USB_DT_ENDPOINT ||
 788	    desc->bEndpointAddress == 0 ||
 789	    desc->bEndpointAddress != uep->addr ||
 790	    le16_to_cpu(desc->wMaxPacketSize) > ep->maxpacket) {
 791		dev_dbg(udc->isp->dev,
 792			"%s: invalid descriptor type %u addr %02x ep addr %02x max packet size %u/%u\n",
 793			__func__, desc->bDescriptorType,
 794			desc->bEndpointAddress, uep->addr,
 795			le16_to_cpu(desc->wMaxPacketSize), ep->maxpacket);
 796		return -EINVAL;
 797	}
 798
 799	switch (usb_endpoint_type(desc)) {
 800	case USB_ENDPOINT_XFER_ISOC:
 801		type = ISP176x_DC_ENDPTYP_ISOC;
 802		break;
 803	case USB_ENDPOINT_XFER_BULK:
 804		type = ISP176x_DC_ENDPTYP_BULK;
 805		break;
 806	case USB_ENDPOINT_XFER_INT:
 807		type = ISP176x_DC_ENDPTYP_INTERRUPT;
 808		break;
 809	case USB_ENDPOINT_XFER_CONTROL:
 810	default:
 811		dev_dbg(udc->isp->dev, "%s: control endpoints unsupported\n",
 812			__func__);
 813		return -EINVAL;
 814	}
 815
 816	spin_lock_irqsave(&udc->lock, flags);
 817
 818	uep->desc = desc;
 819	uep->maxpacket = le16_to_cpu(desc->wMaxPacketSize);
 820	uep->rx_pending = false;
 821	uep->halted = false;
 822	uep->wedged = false;
 823
 824	isp1760_udc_select_ep(udc, uep);
 825
 826	isp1760_udc_write(udc, DC_FFOSZ, uep->maxpacket);
 827	isp1760_udc_write(udc, DC_BUFLEN, uep->maxpacket);
 828
 829	isp1760_udc_write(udc, DC_ENDPTYP, type);
 830	isp1760_udc_set(udc, DC_EPENABLE);
 831
 832	spin_unlock_irqrestore(&udc->lock, flags);
 833
 834	return 0;
 835}
 836
 837static int isp1760_ep_disable(struct usb_ep *ep)
 838{
 839	struct isp1760_ep *uep = ep_to_udc_ep(ep);
 840	struct isp1760_udc *udc = uep->udc;
 841	struct isp1760_request *req, *nreq;
 842	LIST_HEAD(req_list);
 843	unsigned long flags;
 844
 845	dev_dbg(udc->isp->dev, "%s\n", __func__);
 846
 847	spin_lock_irqsave(&udc->lock, flags);
 848
 849	if (!uep->desc) {
 850		dev_dbg(udc->isp->dev, "%s: endpoint not enabled\n", __func__);
 851		spin_unlock_irqrestore(&udc->lock, flags);
 852		return -EINVAL;
 853	}
 854
 855	uep->desc = NULL;
 856	uep->maxpacket = 0;
 857
 858	isp1760_udc_select_ep(udc, uep);
 859	isp1760_udc_clear(udc, DC_EPENABLE);
 860	isp1760_udc_clear(udc, DC_ENDPTYP);
 861
 862	/* TODO Synchronize with the IRQ handler */
 863
 864	list_splice_init(&uep->queue, &req_list);
 865
 866	spin_unlock_irqrestore(&udc->lock, flags);
 867
 868	list_for_each_entry_safe(req, nreq, &req_list, queue) {
 869		list_del(&req->queue);
 870		isp1760_udc_request_complete(uep, req, -ESHUTDOWN);
 871	}
 872
 873	return 0;
 874}
 875
 876static struct usb_request *isp1760_ep_alloc_request(struct usb_ep *ep,
 877						    gfp_t gfp_flags)
 878{
 879	struct isp1760_request *req;
 880
 881	req = kzalloc(sizeof(*req), gfp_flags);
 882	if (!req)
 883		return NULL;
 884
 885	return &req->req;
 886}
 887
 888static void isp1760_ep_free_request(struct usb_ep *ep, struct usb_request *_req)
 889{
 890	struct isp1760_request *req = req_to_udc_req(_req);
 891
 892	kfree(req);
 893}
 894
 895static int isp1760_ep_queue(struct usb_ep *ep, struct usb_request *_req,
 896			    gfp_t gfp_flags)
 897{
 898	struct isp1760_request *req = req_to_udc_req(_req);
 899	struct isp1760_ep *uep = ep_to_udc_ep(ep);
 900	struct isp1760_udc *udc = uep->udc;
 901	bool complete = false;
 902	unsigned long flags;
 903	int ret = 0;
 904
 905	_req->status = -EINPROGRESS;
 906	_req->actual = 0;
 907
 908	spin_lock_irqsave(&udc->lock, flags);
 909
 910	dev_dbg(udc->isp->dev,
 911		"%s: req %p (%u bytes%s) ep %p(0x%02x)\n", __func__, _req,
 912		_req->length, _req->zero ? " (zlp)" : "", uep, uep->addr);
 913
 914	req->ep = uep;
 915
 916	if (uep->addr == 0) {
 917		if (_req->length != udc->ep0_length &&
 918		    udc->ep0_state != ISP1760_CTRL_DATA_IN) {
 919			dev_dbg(udc->isp->dev,
 920				"%s: invalid length %u for req %p\n",
 921				__func__, _req->length, req);
 922			ret = -EINVAL;
 923			goto done;
 924		}
 925
 926		switch (udc->ep0_state) {
 927		case ISP1760_CTRL_DATA_IN:
 928			dev_dbg(udc->isp->dev, "%s: transmitting req %p\n",
 929				__func__, req);
 930
 931			list_add_tail(&req->queue, &uep->queue);
 932			isp1760_udc_transmit(uep, req);
 933			break;
 934
 935		case ISP1760_CTRL_DATA_OUT:
 936			list_add_tail(&req->queue, &uep->queue);
 937			__isp1760_udc_select_ep(udc, uep, USB_DIR_OUT);
 938			isp1760_udc_set(udc, DC_DSEN);
 939			break;
 940
 941		case ISP1760_CTRL_STATUS:
 942			complete = true;
 943			break;
 944
 945		default:
 946			dev_dbg(udc->isp->dev, "%s: invalid ep0 state\n",
 947				__func__);
 948			ret = -EINVAL;
 949			break;
 950		}
 951	} else if (uep->desc) {
 952		bool empty = list_empty(&uep->queue);
 953
 954		list_add_tail(&req->queue, &uep->queue);
 955		if ((uep->addr & USB_DIR_IN) && !uep->halted && empty)
 956			isp1760_udc_transmit(uep, req);
 957		else if (!(uep->addr & USB_DIR_IN) && uep->rx_pending)
 958			complete = isp1760_udc_receive(uep, req);
 959	} else {
 960		dev_dbg(udc->isp->dev,
 961			"%s: can't queue request to disabled ep%02x\n",
 962			__func__, uep->addr);
 963		ret = -ESHUTDOWN;
 964	}
 965
 966done:
 967	if (ret < 0)
 968		req->ep = NULL;
 969
 970	spin_unlock_irqrestore(&udc->lock, flags);
 971
 972	if (complete)
 973		isp1760_udc_request_complete(uep, req, 0);
 974
 975	return ret;
 976}
 977
 978static int isp1760_ep_dequeue(struct usb_ep *ep, struct usb_request *_req)
 979{
 980	struct isp1760_request *req = req_to_udc_req(_req);
 981	struct isp1760_ep *uep = ep_to_udc_ep(ep);
 982	struct isp1760_udc *udc = uep->udc;
 983	unsigned long flags;
 984
 985	dev_dbg(uep->udc->isp->dev, "%s(ep%02x)\n", __func__, uep->addr);
 986
 987	spin_lock_irqsave(&udc->lock, flags);
 988
 989	if (req->ep != uep)
 990		req = NULL;
 991	else
 992		list_del(&req->queue);
 993
 994	spin_unlock_irqrestore(&udc->lock, flags);
 995
 996	if (!req)
 997		return -EINVAL;
 998
 999	isp1760_udc_request_complete(uep, req, -ECONNRESET);
1000	return 0;
1001}
1002
1003static int __isp1760_ep_set_halt(struct isp1760_ep *uep, bool stall, bool wedge)
1004{
1005	struct isp1760_udc *udc = uep->udc;
1006	int ret;
1007
1008	if (!uep->addr) {
1009		/*
1010		 * Halting the control endpoint is only valid as a delayed error
1011		 * response to a SETUP packet. Make sure EP0 is in the right
1012		 * stage and that the gadget isn't trying to clear the halt
1013		 * condition.
1014		 */
1015		if (WARN_ON(udc->ep0_state == ISP1760_CTRL_SETUP || !stall ||
1016			     wedge)) {
1017			return -EINVAL;
1018		}
1019	}
1020
1021	if (uep->addr && !uep->desc) {
1022		dev_dbg(udc->isp->dev, "%s: ep%02x is disabled\n", __func__,
1023			uep->addr);
1024		return -EINVAL;
1025	}
1026
1027	if (uep->addr & USB_DIR_IN) {
1028		/* Refuse to halt IN endpoints with active transfers. */
1029		if (!list_empty(&uep->queue)) {
1030			dev_dbg(udc->isp->dev,
1031				"%s: ep%02x has request pending\n", __func__,
1032				uep->addr);
1033			return -EAGAIN;
1034		}
1035	}
1036
1037	ret = __isp1760_udc_set_halt(uep, stall);
1038	if (ret < 0)
1039		return ret;
1040
1041	if (!uep->addr) {
1042		/*
1043		 * Stalling EP0 completes the control transaction, move back to
1044		 * the SETUP state.
1045		 */
1046		udc->ep0_state = ISP1760_CTRL_SETUP;
1047		return 0;
1048	}
1049
1050	if (wedge)
1051		uep->wedged = true;
1052	else if (!stall)
1053		uep->wedged = false;
1054
1055	return 0;
1056}
1057
1058static int isp1760_ep_set_halt(struct usb_ep *ep, int value)
1059{
1060	struct isp1760_ep *uep = ep_to_udc_ep(ep);
1061	unsigned long flags;
1062	int ret;
1063
1064	dev_dbg(uep->udc->isp->dev, "%s: %s halt on ep%02x\n", __func__,
1065		value ? "set" : "clear", uep->addr);
1066
1067	spin_lock_irqsave(&uep->udc->lock, flags);
1068	ret = __isp1760_ep_set_halt(uep, value, false);
1069	spin_unlock_irqrestore(&uep->udc->lock, flags);
1070
1071	return ret;
1072}
1073
1074static int isp1760_ep_set_wedge(struct usb_ep *ep)
1075{
1076	struct isp1760_ep *uep = ep_to_udc_ep(ep);
1077	unsigned long flags;
1078	int ret;
1079
1080	dev_dbg(uep->udc->isp->dev, "%s: set wedge on ep%02x)\n", __func__,
1081		uep->addr);
1082
1083	spin_lock_irqsave(&uep->udc->lock, flags);
1084	ret = __isp1760_ep_set_halt(uep, true, true);
1085	spin_unlock_irqrestore(&uep->udc->lock, flags);
1086
1087	return ret;
1088}
1089
1090static void isp1760_ep_fifo_flush(struct usb_ep *ep)
1091{
1092	struct isp1760_ep *uep = ep_to_udc_ep(ep);
1093	struct isp1760_udc *udc = uep->udc;
1094	unsigned long flags;
1095
1096	spin_lock_irqsave(&udc->lock, flags);
1097
1098	isp1760_udc_select_ep(udc, uep);
1099
1100	/*
1101	 * Set the CLBUF bit twice to flush both buffers in case double
1102	 * buffering is enabled.
1103	 */
1104	isp1760_udc_set(udc, DC_CLBUF);
1105	isp1760_udc_set(udc, DC_CLBUF);
1106
1107	spin_unlock_irqrestore(&udc->lock, flags);
1108}
1109
1110static const struct usb_ep_ops isp1760_ep_ops = {
1111	.enable = isp1760_ep_enable,
1112	.disable = isp1760_ep_disable,
1113	.alloc_request = isp1760_ep_alloc_request,
1114	.free_request = isp1760_ep_free_request,
1115	.queue = isp1760_ep_queue,
1116	.dequeue = isp1760_ep_dequeue,
1117	.set_halt = isp1760_ep_set_halt,
1118	.set_wedge = isp1760_ep_set_wedge,
1119	.fifo_flush = isp1760_ep_fifo_flush,
1120};
1121
1122/* -----------------------------------------------------------------------------
1123 * Device States
1124 */
1125
1126/* Called with the UDC spinlock held. */
1127static void isp1760_udc_connect(struct isp1760_udc *udc)
1128{
1129	usb_gadget_set_state(&udc->gadget, USB_STATE_POWERED);
1130	mod_timer(&udc->vbus_timer, jiffies + ISP1760_VBUS_POLL_INTERVAL);
1131}
1132
1133/* Called with the UDC spinlock held. */
1134static void isp1760_udc_disconnect(struct isp1760_udc *udc)
1135{
1136	if (udc->gadget.state < USB_STATE_POWERED)
1137		return;
1138
1139	dev_dbg(udc->isp->dev, "Device disconnected in state %u\n",
1140		 udc->gadget.state);
1141
1142	udc->gadget.speed = USB_SPEED_UNKNOWN;
1143	usb_gadget_set_state(&udc->gadget, USB_STATE_ATTACHED);
1144
1145	if (udc->driver->disconnect)
1146		udc->driver->disconnect(&udc->gadget);
1147
1148	del_timer(&udc->vbus_timer);
1149
1150	/* TODO Reset all endpoints ? */
1151}
1152
1153static void isp1760_udc_init_hw(struct isp1760_udc *udc)
1154{
1155	u32 intconf = udc->is_isp1763 ? ISP1763_DC_INTCONF : ISP176x_DC_INTCONF;
1156	u32 intena = udc->is_isp1763 ? ISP1763_DC_INTENABLE :
1157						ISP176x_DC_INTENABLE;
1158
1159	/*
1160	 * The device controller currently shares its interrupt with the host
1161	 * controller, the DC_IRQ polarity and signaling mode are ignored. Set
1162	 * the to active-low level-triggered.
1163	 *
1164	 * Configure the control, in and out pipes to generate interrupts on
1165	 * ACK tokens only (and NYET for the out pipe). The default
1166	 * configuration also generates an interrupt on the first NACK token.
1167	 */
1168	isp1760_reg_write(udc->regs, intconf,
1169			  ISP176x_DC_CDBGMOD_ACK | ISP176x_DC_DDBGMODIN_ACK |
1170			  ISP176x_DC_DDBGMODOUT_ACK);
1171
1172	isp1760_reg_write(udc->regs, intena, DC_IEPRXTX(7) |
1173			  DC_IEPRXTX(6) | DC_IEPRXTX(5) | DC_IEPRXTX(4) |
1174			  DC_IEPRXTX(3) | DC_IEPRXTX(2) | DC_IEPRXTX(1) |
1175			  DC_IEPRXTX(0) | ISP176x_DC_IEP0SETUP |
1176			  ISP176x_DC_IEVBUS | ISP176x_DC_IERESM |
1177			  ISP176x_DC_IESUSP | ISP176x_DC_IEHS_STA |
1178			  ISP176x_DC_IEBRST);
1179
1180	if (udc->connected)
1181		isp1760_set_pullup(udc->isp, true);
1182
1183	isp1760_udc_set(udc, DC_DEVEN);
1184}
1185
1186static void isp1760_udc_reset(struct isp1760_udc *udc)
1187{
1188	unsigned long flags;
1189
1190	spin_lock_irqsave(&udc->lock, flags);
1191
1192	/*
1193	 * The bus reset has reset most registers to their default value,
1194	 * reinitialize the UDC hardware.
1195	 */
1196	isp1760_udc_init_hw(udc);
1197
1198	udc->ep0_state = ISP1760_CTRL_SETUP;
1199	udc->gadget.speed = USB_SPEED_FULL;
1200
1201	usb_gadget_udc_reset(&udc->gadget, udc->driver);
1202
1203	spin_unlock_irqrestore(&udc->lock, flags);
1204}
1205
1206static void isp1760_udc_suspend(struct isp1760_udc *udc)
1207{
1208	if (udc->gadget.state < USB_STATE_DEFAULT)
1209		return;
1210
1211	if (udc->driver->suspend)
1212		udc->driver->suspend(&udc->gadget);
1213}
1214
1215static void isp1760_udc_resume(struct isp1760_udc *udc)
1216{
1217	if (udc->gadget.state < USB_STATE_DEFAULT)
1218		return;
1219
1220	if (udc->driver->resume)
1221		udc->driver->resume(&udc->gadget);
1222}
1223
1224/* -----------------------------------------------------------------------------
1225 * Gadget Operations
1226 */
1227
1228static int isp1760_udc_get_frame(struct usb_gadget *gadget)
1229{
1230	struct isp1760_udc *udc = gadget_to_udc(gadget);
1231
1232	return isp1760_udc_read(udc, DC_FRAMENUM);
1233}
1234
1235static int isp1760_udc_wakeup(struct usb_gadget *gadget)
1236{
1237	struct isp1760_udc *udc = gadget_to_udc(gadget);
1238
1239	dev_dbg(udc->isp->dev, "%s\n", __func__);
1240	return -ENOTSUPP;
1241}
1242
1243static int isp1760_udc_set_selfpowered(struct usb_gadget *gadget,
1244				       int is_selfpowered)
1245{
1246	struct isp1760_udc *udc = gadget_to_udc(gadget);
1247
1248	if (is_selfpowered)
1249		udc->devstatus |= 1 << USB_DEVICE_SELF_POWERED;
1250	else
1251		udc->devstatus &= ~(1 << USB_DEVICE_SELF_POWERED);
1252
1253	return 0;
1254}
1255
1256static int isp1760_udc_pullup(struct usb_gadget *gadget, int is_on)
1257{
1258	struct isp1760_udc *udc = gadget_to_udc(gadget);
1259
1260	isp1760_set_pullup(udc->isp, is_on);
1261	udc->connected = is_on;
1262
1263	return 0;
1264}
1265
1266static int isp1760_udc_start(struct usb_gadget *gadget,
1267			     struct usb_gadget_driver *driver)
1268{
1269	struct isp1760_udc *udc = gadget_to_udc(gadget);
1270	unsigned long flags;
1271
1272	/* The hardware doesn't support low speed. */
1273	if (driver->max_speed < USB_SPEED_FULL) {
1274		dev_err(udc->isp->dev, "Invalid gadget driver\n");
1275		return -EINVAL;
1276	}
1277
1278	spin_lock_irqsave(&udc->lock, flags);
1279
1280	if (udc->driver) {
1281		dev_err(udc->isp->dev, "UDC already has a gadget driver\n");
1282		spin_unlock_irqrestore(&udc->lock, flags);
1283		return -EBUSY;
1284	}
1285
1286	udc->driver = driver;
1287
1288	spin_unlock_irqrestore(&udc->lock, flags);
1289
1290	dev_dbg(udc->isp->dev, "starting UDC with driver %s\n",
1291		driver->function);
1292
1293	udc->devstatus = 0;
1294	udc->connected = true;
1295
1296	usb_gadget_set_state(&udc->gadget, USB_STATE_ATTACHED);
1297
1298	/* DMA isn't supported yet, don't enable the DMA clock. */
1299	isp1760_udc_set(udc, DC_GLINTENA);
1300
1301	isp1760_udc_init_hw(udc);
1302
1303	dev_dbg(udc->isp->dev, "UDC started with driver %s\n",
1304		driver->function);
1305
1306	return 0;
1307}
1308
1309static int isp1760_udc_stop(struct usb_gadget *gadget)
1310{
1311	struct isp1760_udc *udc = gadget_to_udc(gadget);
1312	u32 mode_reg = udc->is_isp1763 ? ISP1763_DC_MODE : ISP176x_DC_MODE;
1313	unsigned long flags;
1314
1315	dev_dbg(udc->isp->dev, "%s\n", __func__);
1316
1317	del_timer_sync(&udc->vbus_timer);
1318
1319	isp1760_reg_write(udc->regs, mode_reg, 0);
1320
1321	spin_lock_irqsave(&udc->lock, flags);
1322	udc->driver = NULL;
1323	spin_unlock_irqrestore(&udc->lock, flags);
1324
1325	return 0;
1326}
1327
1328static const struct usb_gadget_ops isp1760_udc_ops = {
1329	.get_frame = isp1760_udc_get_frame,
1330	.wakeup = isp1760_udc_wakeup,
1331	.set_selfpowered = isp1760_udc_set_selfpowered,
1332	.pullup = isp1760_udc_pullup,
1333	.udc_start = isp1760_udc_start,
1334	.udc_stop = isp1760_udc_stop,
1335};
1336
1337/* -----------------------------------------------------------------------------
1338 * Interrupt Handling
1339 */
1340
1341static u32 isp1760_udc_irq_get_status(struct isp1760_udc *udc)
1342{
1343	u32 status;
1344
1345	if (udc->is_isp1763) {
1346		status = isp1760_reg_read(udc->regs, ISP1763_DC_INTERRUPT)
1347			& isp1760_reg_read(udc->regs, ISP1763_DC_INTENABLE);
1348		isp1760_reg_write(udc->regs, ISP1763_DC_INTERRUPT, status);
1349	} else {
1350		status = isp1760_reg_read(udc->regs, ISP176x_DC_INTERRUPT)
1351			& isp1760_reg_read(udc->regs, ISP176x_DC_INTENABLE);
1352		isp1760_reg_write(udc->regs, ISP176x_DC_INTERRUPT, status);
1353	}
1354
1355	return status;
1356}
1357
1358static irqreturn_t isp1760_udc_irq(int irq, void *dev)
1359{
1360	struct isp1760_udc *udc = dev;
1361	unsigned int i;
1362	u32 status;
1363
1364	status = isp1760_udc_irq_get_status(udc);
1365
1366	if (status & ISP176x_DC_IEVBUS) {
1367		dev_dbg(udc->isp->dev, "%s(VBUS)\n", __func__);
1368		/* The VBUS interrupt is only triggered when VBUS appears. */
1369		spin_lock(&udc->lock);
1370		isp1760_udc_connect(udc);
1371		spin_unlock(&udc->lock);
1372	}
1373
1374	if (status & ISP176x_DC_IEBRST) {
1375		dev_dbg(udc->isp->dev, "%s(BRST)\n", __func__);
1376
1377		isp1760_udc_reset(udc);
1378	}
1379
1380	for (i = 0; i <= 7; ++i) {
1381		struct isp1760_ep *ep = &udc->ep[i*2];
1382
1383		if (status & DC_IEPTX(i)) {
1384			dev_dbg(udc->isp->dev, "%s(EPTX%u)\n", __func__, i);
1385			isp1760_ep_tx_complete(ep);
1386		}
1387
1388		if (status & DC_IEPRX(i)) {
1389			dev_dbg(udc->isp->dev, "%s(EPRX%u)\n", __func__, i);
1390			isp1760_ep_rx_ready(i ? ep - 1 : ep);
1391		}
1392	}
1393
1394	if (status & ISP176x_DC_IEP0SETUP) {
1395		dev_dbg(udc->isp->dev, "%s(EP0SETUP)\n", __func__);
1396
1397		isp1760_ep0_setup(udc);
1398	}
1399
1400	if (status & ISP176x_DC_IERESM) {
1401		dev_dbg(udc->isp->dev, "%s(RESM)\n", __func__);
1402		isp1760_udc_resume(udc);
1403	}
1404
1405	if (status & ISP176x_DC_IESUSP) {
1406		dev_dbg(udc->isp->dev, "%s(SUSP)\n", __func__);
1407
1408		spin_lock(&udc->lock);
1409		if (!isp1760_udc_is_set(udc, DC_VBUSSTAT))
1410			isp1760_udc_disconnect(udc);
1411		else
1412			isp1760_udc_suspend(udc);
1413		spin_unlock(&udc->lock);
1414	}
1415
1416	if (status & ISP176x_DC_IEHS_STA) {
1417		dev_dbg(udc->isp->dev, "%s(HS_STA)\n", __func__);
1418		udc->gadget.speed = USB_SPEED_HIGH;
1419	}
1420
1421	return status ? IRQ_HANDLED : IRQ_NONE;
1422}
1423
1424static void isp1760_udc_vbus_poll(struct timer_list *t)
1425{
1426	struct isp1760_udc *udc = from_timer(udc, t, vbus_timer);
1427	unsigned long flags;
1428
1429	spin_lock_irqsave(&udc->lock, flags);
1430
1431	if (!(isp1760_udc_is_set(udc, DC_VBUSSTAT)))
1432		isp1760_udc_disconnect(udc);
1433	else if (udc->gadget.state >= USB_STATE_POWERED)
1434		mod_timer(&udc->vbus_timer,
1435			  jiffies + ISP1760_VBUS_POLL_INTERVAL);
1436
1437	spin_unlock_irqrestore(&udc->lock, flags);
1438}
1439
1440/* -----------------------------------------------------------------------------
1441 * Registration
1442 */
1443
1444static void isp1760_udc_init_eps(struct isp1760_udc *udc)
1445{
1446	unsigned int i;
1447
1448	INIT_LIST_HEAD(&udc->gadget.ep_list);
1449
1450	for (i = 0; i < ARRAY_SIZE(udc->ep); ++i) {
1451		struct isp1760_ep *ep = &udc->ep[i];
1452		unsigned int ep_num = (i + 1) / 2;
1453		bool is_in = !(i & 1);
1454
1455		ep->udc = udc;
1456
1457		INIT_LIST_HEAD(&ep->queue);
1458
1459		ep->addr = (ep_num && is_in ? USB_DIR_IN : USB_DIR_OUT)
1460			 | ep_num;
1461		ep->desc = NULL;
1462
1463		sprintf(ep->name, "ep%u%s", ep_num,
1464			ep_num ? (is_in ? "in" : "out") : "");
1465
1466		ep->ep.ops = &isp1760_ep_ops;
1467		ep->ep.name = ep->name;
1468
1469		/*
1470		 * Hardcode the maximum packet sizes for now, to 64 bytes for
1471		 * the control endpoint and 512 bytes for all other endpoints.
1472		 * This fits in the 8kB FIFO without double-buffering.
1473		 */
1474		if (ep_num == 0) {
1475			usb_ep_set_maxpacket_limit(&ep->ep, 64);
1476			ep->ep.caps.type_control = true;
1477			ep->ep.caps.dir_in = true;
1478			ep->ep.caps.dir_out = true;
1479			ep->maxpacket = 64;
1480			udc->gadget.ep0 = &ep->ep;
1481		} else {
1482			usb_ep_set_maxpacket_limit(&ep->ep, 512);
1483			ep->ep.caps.type_iso = true;
1484			ep->ep.caps.type_bulk = true;
1485			ep->ep.caps.type_int = true;
1486			ep->maxpacket = 0;
1487			list_add_tail(&ep->ep.ep_list, &udc->gadget.ep_list);
1488		}
1489
1490		if (is_in)
1491			ep->ep.caps.dir_in = true;
1492		else
1493			ep->ep.caps.dir_out = true;
1494	}
1495}
1496
1497static int isp1760_udc_init(struct isp1760_udc *udc)
1498{
1499	u32 mode_reg = udc->is_isp1763 ? ISP1763_DC_MODE : ISP176x_DC_MODE;
1500	u16 scratch;
1501	u32 chipid;
1502
1503	/*
1504	 * Check that the controller is present by writing to the scratch
1505	 * register, modifying the bus pattern by reading from the chip ID
1506	 * register, and reading the scratch register value back. The chip ID
1507	 * and scratch register contents must match the expected values.
1508	 */
1509	isp1760_udc_write(udc, DC_SCRATCH, 0xbabe);
1510	chipid = isp1760_udc_read(udc, DC_CHIP_ID_HIGH) << 16;
1511	chipid |= isp1760_udc_read(udc, DC_CHIP_ID_LOW);
1512	scratch = isp1760_udc_read(udc, DC_SCRATCH);
1513
1514	if (scratch != 0xbabe) {
1515		dev_err(udc->isp->dev,
1516			"udc: scratch test failed (0x%04x/0x%08x)\n",
1517			scratch, chipid);
1518		return -ENODEV;
1519	}
1520
1521	if (chipid != 0x00011582 && chipid != 0x00158210 &&
1522	    chipid != 0x00176320) {
1523		dev_err(udc->isp->dev, "udc: invalid chip ID 0x%08x\n", chipid);
1524		return -ENODEV;
1525	}
1526
1527	/* Reset the device controller. */
1528	isp1760_udc_set(udc, DC_SFRESET);
1529	usleep_range(10000, 11000);
1530	isp1760_reg_write(udc->regs, mode_reg, 0);
1531	usleep_range(10000, 11000);
1532
1533	return 0;
1534}
1535
1536int isp1760_udc_register(struct isp1760_device *isp, int irq,
1537			 unsigned long irqflags)
1538{
1539	struct isp1760_udc *udc = &isp->udc;
1540	int ret;
1541
1542	udc->irq = -1;
1543	udc->isp = isp;
1544
1545	spin_lock_init(&udc->lock);
1546	timer_setup(&udc->vbus_timer, isp1760_udc_vbus_poll, 0);
1547
1548	ret = isp1760_udc_init(udc);
1549	if (ret < 0)
1550		return ret;
1551
1552	udc->irqname = kasprintf(GFP_KERNEL, "%s (udc)", dev_name(isp->dev));
1553	if (!udc->irqname)
1554		return -ENOMEM;
1555
1556	ret = request_irq(irq, isp1760_udc_irq, IRQF_SHARED | irqflags,
1557			  udc->irqname, udc);
1558	if (ret < 0)
1559		goto error;
1560
1561	udc->irq = irq;
1562
1563	/*
1564	 * Initialize the gadget static fields and register its device. Gadget
1565	 * fields that vary during the life time of the gadget are initialized
1566	 * by the UDC core.
1567	 */
1568	udc->gadget.ops = &isp1760_udc_ops;
1569	udc->gadget.speed = USB_SPEED_UNKNOWN;
1570	udc->gadget.max_speed = USB_SPEED_HIGH;
1571	udc->gadget.name = "isp1761_udc";
1572
1573	isp1760_udc_init_eps(udc);
1574
1575	ret = usb_add_gadget_udc(isp->dev, &udc->gadget);
1576	if (ret < 0)
1577		goto error;
1578
1579	return 0;
1580
1581error:
1582	if (udc->irq >= 0)
1583		free_irq(udc->irq, udc);
1584	kfree(udc->irqname);
1585
1586	return ret;
1587}
1588
1589void isp1760_udc_unregister(struct isp1760_device *isp)
1590{
1591	struct isp1760_udc *udc = &isp->udc;
1592
1593	if (!udc->isp)
1594		return;
1595
1596	usb_del_gadget_udc(&udc->gadget);
1597
1598	free_irq(udc->irq, udc);
1599	kfree(udc->irqname);
1600}