1/*
   2 * udc.c - ChipIdea UDC driver
   3 *
   4 * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
   5 *
   6 * Author: David Lopo
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License version 2 as
  10 * published by the Free Software Foundation.
  11 */
  12
  13#include <linux/delay.h>
  14#include <linux/device.h>
  15#include <linux/dmapool.h>
  16#include <linux/err.h>
  17#include <linux/irqreturn.h>
  18#include <linux/kernel.h>
  19#include <linux/slab.h>
  20#include <linux/pm_runtime.h>
  21#include <linux/usb/ch9.h>
  22#include <linux/usb/gadget.h>
  23#include <linux/usb/otg-fsm.h>
  24#include <linux/usb/chipidea.h>
  25
  26#include "ci.h"
  27#include "udc.h"
  28#include "bits.h"
 
  29#include "otg.h"
  30#include "otg_fsm.h"
  31
  32/* control endpoint description */
  33static const struct usb_endpoint_descriptor
  34ctrl_endpt_out_desc = {
  35	.bLength         = USB_DT_ENDPOINT_SIZE,
  36	.bDescriptorType = USB_DT_ENDPOINT,
  37
  38	.bEndpointAddress = USB_DIR_OUT,
  39	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
  40	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
  41};
  42
  43static const struct usb_endpoint_descriptor
  44ctrl_endpt_in_desc = {
  45	.bLength         = USB_DT_ENDPOINT_SIZE,
  46	.bDescriptorType = USB_DT_ENDPOINT,
  47
  48	.bEndpointAddress = USB_DIR_IN,
  49	.bmAttributes    = USB_ENDPOINT_XFER_CONTROL,
  50	.wMaxPacketSize  = cpu_to_le16(CTRL_PAYLOAD_MAX),
  51};
  52
  53/**
  54 * hw_ep_bit: calculates the bit number
  55 * @num: endpoint number
  56 * @dir: endpoint direction
  57 *
  58 * This function returns bit number
  59 */
  60static inline int hw_ep_bit(int num, int dir)
  61{
  62	return num + (dir ? 16 : 0);
  63}
  64
  65static inline int ep_to_bit(struct ci_hdrc *ci, int n)
  66{
  67	int fill = 16 - ci->hw_ep_max / 2;
  68
  69	if (n >= ci->hw_ep_max / 2)
  70		n += fill;
  71
  72	return n;
  73}
  74
  75/**
  76 * hw_device_state: enables/disables interrupts (execute without interruption)
  77 * @dma: 0 => disable, !0 => enable and set dma engine
  78 *
  79 * This function returns an error code
  80 */
  81static int hw_device_state(struct ci_hdrc *ci, u32 dma)
  82{
  83	if (dma) {
  84		hw_write(ci, OP_ENDPTLISTADDR, ~0, dma);
  85		/* interrupt, error, port change, reset, sleep/suspend */
  86		hw_write(ci, OP_USBINTR, ~0,
  87			     USBi_UI|USBi_UEI|USBi_PCI|USBi_URI|USBi_SLI);
 
  88	} else {
  89		hw_write(ci, OP_USBINTR, ~0, 0);
 
  90	}
  91	return 0;
  92}
  93
  94/**
  95 * hw_ep_flush: flush endpoint fifo (execute without interruption)
  96 * @num: endpoint number
  97 * @dir: endpoint direction
  98 *
  99 * This function returns an error code
 100 */
 101static int hw_ep_flush(struct ci_hdrc *ci, int num, int dir)
 102{
 103	int n = hw_ep_bit(num, dir);
 104
 105	do {
 106		/* flush any pending transfer */
 107		hw_write(ci, OP_ENDPTFLUSH, ~0, BIT(n));
 108		while (hw_read(ci, OP_ENDPTFLUSH, BIT(n)))
 109			cpu_relax();
 110	} while (hw_read(ci, OP_ENDPTSTAT, BIT(n)));
 111
 112	return 0;
 113}
 114
 115/**
 116 * hw_ep_disable: disables endpoint (execute without interruption)
 117 * @num: endpoint number
 118 * @dir: endpoint direction
 119 *
 120 * This function returns an error code
 121 */
 122static int hw_ep_disable(struct ci_hdrc *ci, int num, int dir)
 123{
 124	hw_ep_flush(ci, num, dir);
 125	hw_write(ci, OP_ENDPTCTRL + num,
 126		 dir ? ENDPTCTRL_TXE : ENDPTCTRL_RXE, 0);
 127	return 0;
 128}
 129
 130/**
 131 * hw_ep_enable: enables endpoint (execute without interruption)
 132 * @num:  endpoint number
 133 * @dir:  endpoint direction
 134 * @type: endpoint type
 135 *
 136 * This function returns an error code
 137 */
 138static int hw_ep_enable(struct ci_hdrc *ci, int num, int dir, int type)
 139{
 140	u32 mask, data;
 141
 142	if (dir) {
 143		mask  = ENDPTCTRL_TXT;  /* type    */
 144		data  = type << __ffs(mask);
 145
 146		mask |= ENDPTCTRL_TXS;  /* unstall */
 147		mask |= ENDPTCTRL_TXR;  /* reset data toggle */
 148		data |= ENDPTCTRL_TXR;
 149		mask |= ENDPTCTRL_TXE;  /* enable  */
 150		data |= ENDPTCTRL_TXE;
 151	} else {
 152		mask  = ENDPTCTRL_RXT;  /* type    */
 153		data  = type << __ffs(mask);
 154
 155		mask |= ENDPTCTRL_RXS;  /* unstall */
 156		mask |= ENDPTCTRL_RXR;  /* reset data toggle */
 157		data |= ENDPTCTRL_RXR;
 158		mask |= ENDPTCTRL_RXE;  /* enable  */
 159		data |= ENDPTCTRL_RXE;
 160	}
 161	hw_write(ci, OP_ENDPTCTRL + num, mask, data);
 162	return 0;
 163}
 164
 165/**
 166 * hw_ep_get_halt: return endpoint halt status
 167 * @num: endpoint number
 168 * @dir: endpoint direction
 169 *
 170 * This function returns 1 if endpoint halted
 171 */
 172static int hw_ep_get_halt(struct ci_hdrc *ci, int num, int dir)
 173{
 174	u32 mask = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
 175
 176	return hw_read(ci, OP_ENDPTCTRL + num, mask) ? 1 : 0;
 177}
 178
 179/**
 180 * hw_ep_prime: primes endpoint (execute without interruption)
 181 * @num:     endpoint number
 182 * @dir:     endpoint direction
 183 * @is_ctrl: true if control endpoint
 184 *
 185 * This function returns an error code
 186 */
 187static int hw_ep_prime(struct ci_hdrc *ci, int num, int dir, int is_ctrl)
 188{
 189	int n = hw_ep_bit(num, dir);
 190
 191	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
 192		return -EAGAIN;
 193
 194	hw_write(ci, OP_ENDPTPRIME, ~0, BIT(n));
 195
 196	while (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
 197		cpu_relax();
 198	if (is_ctrl && dir == RX && hw_read(ci, OP_ENDPTSETUPSTAT, BIT(num)))
 199		return -EAGAIN;
 200
 201	/* status shoult be tested according with manual but it doesn't work */
 202	return 0;
 203}
 204
 205/**
 206 * hw_ep_set_halt: configures ep halt & resets data toggle after clear (execute
 207 *                 without interruption)
 208 * @num:   endpoint number
 209 * @dir:   endpoint direction
 210 * @value: true => stall, false => unstall
 211 *
 212 * This function returns an error code
 213 */
 214static int hw_ep_set_halt(struct ci_hdrc *ci, int num, int dir, int value)
 215{
 216	if (value != 0 && value != 1)
 217		return -EINVAL;
 218
 219	do {
 220		enum ci_hw_regs reg = OP_ENDPTCTRL + num;
 221		u32 mask_xs = dir ? ENDPTCTRL_TXS : ENDPTCTRL_RXS;
 222		u32 mask_xr = dir ? ENDPTCTRL_TXR : ENDPTCTRL_RXR;
 223
 224		/* data toggle - reserved for EP0 but it's in ESS */
 225		hw_write(ci, reg, mask_xs|mask_xr,
 226			  value ? mask_xs : mask_xr);
 227	} while (value != hw_ep_get_halt(ci, num, dir));
 228
 229	return 0;
 230}
 231
 232/**
 233 * hw_is_port_high_speed: test if port is high speed
 234 *
 235 * This function returns true if high speed port
 236 */
 237static int hw_port_is_high_speed(struct ci_hdrc *ci)
 238{
 239	return ci->hw_bank.lpm ? hw_read(ci, OP_DEVLC, DEVLC_PSPD) :
 240		hw_read(ci, OP_PORTSC, PORTSC_HSP);
 241}
 242
 243/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 244 * hw_test_and_clear_complete: test & clear complete status (execute without
 245 *                             interruption)
 246 * @n: endpoint number
 247 *
 248 * This function returns complete status
 249 */
 250static int hw_test_and_clear_complete(struct ci_hdrc *ci, int n)
 251{
 252	n = ep_to_bit(ci, n);
 253	return hw_test_and_clear(ci, OP_ENDPTCOMPLETE, BIT(n));
 254}
 255
 256/**
 257 * hw_test_and_clear_intr_active: test & clear active interrupts (execute
 258 *                                without interruption)
 259 *
 260 * This function returns active interrutps
 261 */
 262static u32 hw_test_and_clear_intr_active(struct ci_hdrc *ci)
 263{
 264	u32 reg = hw_read_intr_status(ci) & hw_read_intr_enable(ci);
 265
 266	hw_write(ci, OP_USBSTS, ~0, reg);
 267	return reg;
 268}
 269
 270/**
 271 * hw_test_and_clear_setup_guard: test & clear setup guard (execute without
 272 *                                interruption)
 273 *
 274 * This function returns guard value
 275 */
 276static int hw_test_and_clear_setup_guard(struct ci_hdrc *ci)
 277{
 278	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, 0);
 279}
 280
 281/**
 282 * hw_test_and_set_setup_guard: test & set setup guard (execute without
 283 *                              interruption)
 284 *
 285 * This function returns guard value
 286 */
 287static int hw_test_and_set_setup_guard(struct ci_hdrc *ci)
 288{
 289	return hw_test_and_write(ci, OP_USBCMD, USBCMD_SUTW, USBCMD_SUTW);
 290}
 291
 292/**
 293 * hw_usb_set_address: configures USB address (execute without interruption)
 294 * @value: new USB address
 295 *
 296 * This function explicitly sets the address, without the "USBADRA" (advance)
 297 * feature, which is not supported by older versions of the controller.
 298 */
 299static void hw_usb_set_address(struct ci_hdrc *ci, u8 value)
 300{
 301	hw_write(ci, OP_DEVICEADDR, DEVICEADDR_USBADR,
 302		 value << __ffs(DEVICEADDR_USBADR));
 303}
 304
 305/**
 306 * hw_usb_reset: restart device after a bus reset (execute without
 307 *               interruption)
 308 *
 309 * This function returns an error code
 310 */
 311static int hw_usb_reset(struct ci_hdrc *ci)
 312{
 313	hw_usb_set_address(ci, 0);
 314
 315	/* ESS flushes only at end?!? */
 316	hw_write(ci, OP_ENDPTFLUSH,    ~0, ~0);
 317
 318	/* clear setup token semaphores */
 319	hw_write(ci, OP_ENDPTSETUPSTAT, 0,  0);
 320
 321	/* clear complete status */
 322	hw_write(ci, OP_ENDPTCOMPLETE,  0,  0);
 323
 324	/* wait until all bits cleared */
 325	while (hw_read(ci, OP_ENDPTPRIME, ~0))
 326		udelay(10);             /* not RTOS friendly */
 327
 328	/* reset all endpoints ? */
 329
 330	/* reset internal status and wait for further instructions
 331	   no need to verify the port reset status (ESS does it) */
 332
 333	return 0;
 334}
 335
 336/******************************************************************************
 337 * UTIL block
 338 *****************************************************************************/
 339
 340static int add_td_to_list(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq,
 341			  unsigned length)
 342{
 343	int i;
 344	u32 temp;
 345	struct td_node *lastnode, *node = kzalloc(sizeof(struct td_node),
 346						  GFP_ATOMIC);
 347
 348	if (node == NULL)
 349		return -ENOMEM;
 350
 351	node->ptr = dma_pool_zalloc(hwep->td_pool, GFP_ATOMIC,
 352				   &node->dma);
 353	if (node->ptr == NULL) {
 354		kfree(node);
 355		return -ENOMEM;
 356	}
 357
 
 358	node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
 359	node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
 360	node->ptr->token |= cpu_to_le32(TD_STATUS_ACTIVE);
 361	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
 362		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
 363
 364		if (hwreq->req.length == 0
 365				|| hwreq->req.length % hwep->ep.maxpacket)
 366			mul++;
 367		node->ptr->token |= mul << __ffs(TD_MULTO);
 368	}
 369
 370	temp = (u32) (hwreq->req.dma + hwreq->req.actual);
 371	if (length) {
 372		node->ptr->page[0] = cpu_to_le32(temp);
 373		for (i = 1; i < TD_PAGE_COUNT; i++) {
 374			u32 page = temp + i * CI_HDRC_PAGE_SIZE;
 375			page &= ~TD_RESERVED_MASK;
 376			node->ptr->page[i] = cpu_to_le32(page);
 377		}
 378	}
 379
 380	hwreq->req.actual += length;
 381
 382	if (!list_empty(&hwreq->tds)) {
 383		/* get the last entry */
 384		lastnode = list_entry(hwreq->tds.prev,
 385				struct td_node, td);
 386		lastnode->ptr->next = cpu_to_le32(node->dma);
 387	}
 388
 389	INIT_LIST_HEAD(&node->td);
 390	list_add_tail(&node->td, &hwreq->tds);
 391
 392	return 0;
 393}
 394
 395/**
 396 * _usb_addr: calculates endpoint address from direction & number
 397 * @ep:  endpoint
 398 */
 399static inline u8 _usb_addr(struct ci_hw_ep *ep)
 400{
 401	return ((ep->dir == TX) ? USB_ENDPOINT_DIR_MASK : 0) | ep->num;
 402}
 403
 404/**
 405 * _hardware_enqueue: configures a request at hardware level
 
 406 * @hwep:   endpoint
 407 * @hwreq:  request
 408 *
 409 * This function returns an error code
 410 */
 411static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
 412{
 413	struct ci_hdrc *ci = hwep->ci;
 414	int ret = 0;
 415	unsigned rest = hwreq->req.length;
 416	int pages = TD_PAGE_COUNT;
 417	struct td_node *firstnode, *lastnode;
 418
 419	/* don't queue twice */
 420	if (hwreq->req.status == -EALREADY)
 421		return -EALREADY;
 422
 423	hwreq->req.status = -EALREADY;
 424
 425	ret = usb_gadget_map_request(&ci->gadget, &hwreq->req, hwep->dir);
 426	if (ret)
 427		return ret;
 428
 429	/*
 430	 * The first buffer could be not page aligned.
 431	 * In that case we have to span into one extra td.
 432	 */
 433	if (hwreq->req.dma % PAGE_SIZE)
 434		pages--;
 435
 436	if (rest == 0) {
 437		ret = add_td_to_list(hwep, hwreq, 0);
 438		if (ret < 0)
 439			goto done;
 440	}
 441
 442	while (rest > 0) {
 443		unsigned count = min(hwreq->req.length - hwreq->req.actual,
 444					(unsigned)(pages * CI_HDRC_PAGE_SIZE));
 445		ret = add_td_to_list(hwep, hwreq, count);
 446		if (ret < 0)
 447			goto done;
 448
 449		rest -= count;
 450	}
 451
 452	if (hwreq->req.zero && hwreq->req.length && hwep->dir == TX
 453	    && (hwreq->req.length % hwep->ep.maxpacket == 0)) {
 454		ret = add_td_to_list(hwep, hwreq, 0);
 455		if (ret < 0)
 456			goto done;
 457	}
 458
 459	firstnode = list_first_entry(&hwreq->tds, struct td_node, td);
 460
 461	lastnode = list_entry(hwreq->tds.prev,
 462		struct td_node, td);
 463
 464	lastnode->ptr->next = cpu_to_le32(TD_TERMINATE);
 465	if (!hwreq->req.no_interrupt)
 466		lastnode->ptr->token |= cpu_to_le32(TD_IOC);
 467	wmb();
 468
 469	hwreq->req.actual = 0;
 470	if (!list_empty(&hwep->qh.queue)) {
 471		struct ci_hw_req *hwreqprev;
 472		int n = hw_ep_bit(hwep->num, hwep->dir);
 473		int tmp_stat;
 474		struct td_node *prevlastnode;
 475		u32 next = firstnode->dma & TD_ADDR_MASK;
 476
 477		hwreqprev = list_entry(hwep->qh.queue.prev,
 478				struct ci_hw_req, queue);
 479		prevlastnode = list_entry(hwreqprev->tds.prev,
 480				struct td_node, td);
 481
 482		prevlastnode->ptr->next = cpu_to_le32(next);
 483		wmb();
 484		if (hw_read(ci, OP_ENDPTPRIME, BIT(n)))
 485			goto done;
 486		do {
 487			hw_write(ci, OP_USBCMD, USBCMD_ATDTW, USBCMD_ATDTW);
 488			tmp_stat = hw_read(ci, OP_ENDPTSTAT, BIT(n));
 489		} while (!hw_read(ci, OP_USBCMD, USBCMD_ATDTW));
 490		hw_write(ci, OP_USBCMD, USBCMD_ATDTW, 0);
 491		if (tmp_stat)
 492			goto done;
 493	}
 494
 495	/*  QH configuration */
 496	hwep->qh.ptr->td.next = cpu_to_le32(firstnode->dma);
 497	hwep->qh.ptr->td.token &=
 498		cpu_to_le32(~(TD_STATUS_HALTED|TD_STATUS_ACTIVE));
 499
 500	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
 501		u32 mul = hwreq->req.length / hwep->ep.maxpacket;
 502
 503		if (hwreq->req.length == 0
 504				|| hwreq->req.length % hwep->ep.maxpacket)
 505			mul++;
 506		hwep->qh.ptr->cap |= mul << __ffs(QH_MULT);
 507	}
 508
 509	wmb();   /* synchronize before ep prime */
 510
 511	ret = hw_ep_prime(ci, hwep->num, hwep->dir,
 512			   hwep->type == USB_ENDPOINT_XFER_CONTROL);
 513done:
 514	return ret;
 515}
 516
 517/*
 518 * free_pending_td: remove a pending request for the endpoint
 519 * @hwep: endpoint
 520 */
 521static void free_pending_td(struct ci_hw_ep *hwep)
 522{
 523	struct td_node *pending = hwep->pending_td;
 524
 525	dma_pool_free(hwep->td_pool, pending->ptr, pending->dma);
 526	hwep->pending_td = NULL;
 527	kfree(pending);
 528}
 529
 530static int reprime_dtd(struct ci_hdrc *ci, struct ci_hw_ep *hwep,
 531					   struct td_node *node)
 532{
 533	hwep->qh.ptr->td.next = node->dma;
 534	hwep->qh.ptr->td.token &=
 535		cpu_to_le32(~(TD_STATUS_HALTED | TD_STATUS_ACTIVE));
 536
 537	/* Synchronize before ep prime */
 538	wmb();
 539
 540	return hw_ep_prime(ci, hwep->num, hwep->dir,
 541				hwep->type == USB_ENDPOINT_XFER_CONTROL);
 542}
 543
 544/**
 545 * _hardware_dequeue: handles a request at hardware level
 546 * @gadget: gadget
 547 * @hwep:   endpoint
 548 *
 549 * This function returns an error code
 550 */
 551static int _hardware_dequeue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq)
 552{
 553	u32 tmptoken;
 554	struct td_node *node, *tmpnode;
 555	unsigned remaining_length;
 556	unsigned actual = hwreq->req.length;
 557	struct ci_hdrc *ci = hwep->ci;
 558
 559	if (hwreq->req.status != -EALREADY)
 560		return -EINVAL;
 561
 562	hwreq->req.status = 0;
 563
 564	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
 565		tmptoken = le32_to_cpu(node->ptr->token);
 566		if ((TD_STATUS_ACTIVE & tmptoken) != 0) {
 567			int n = hw_ep_bit(hwep->num, hwep->dir);
 568
 569			if (ci->rev == CI_REVISION_24)
 570				if (!hw_read(ci, OP_ENDPTSTAT, BIT(n)))
 571					reprime_dtd(ci, hwep, node);
 572			hwreq->req.status = -EALREADY;
 573			return -EBUSY;
 574		}
 575
 576		remaining_length = (tmptoken & TD_TOTAL_BYTES);
 577		remaining_length >>= __ffs(TD_TOTAL_BYTES);
 578		actual -= remaining_length;
 579
 580		hwreq->req.status = tmptoken & TD_STATUS;
 581		if ((TD_STATUS_HALTED & hwreq->req.status)) {
 582			hwreq->req.status = -EPIPE;
 583			break;
 584		} else if ((TD_STATUS_DT_ERR & hwreq->req.status)) {
 585			hwreq->req.status = -EPROTO;
 586			break;
 587		} else if ((TD_STATUS_TR_ERR & hwreq->req.status)) {
 588			hwreq->req.status = -EILSEQ;
 589			break;
 590		}
 591
 592		if (remaining_length) {
 593			if (hwep->dir) {
 594				hwreq->req.status = -EPROTO;
 595				break;
 596			}
 597		}
 598		/*
 599		 * As the hardware could still address the freed td
 600		 * which will run the udc unusable, the cleanup of the
 601		 * td has to be delayed by one.
 602		 */
 603		if (hwep->pending_td)
 604			free_pending_td(hwep);
 605
 606		hwep->pending_td = node;
 607		list_del_init(&node->td);
 608	}
 609
 610	usb_gadget_unmap_request(&hwep->ci->gadget, &hwreq->req, hwep->dir);
 611
 612	hwreq->req.actual += actual;
 613
 614	if (hwreq->req.status)
 615		return hwreq->req.status;
 616
 617	return hwreq->req.actual;
 618}
 619
 620/**
 621 * _ep_nuke: dequeues all endpoint requests
 622 * @hwep: endpoint
 623 *
 624 * This function returns an error code
 625 * Caller must hold lock
 626 */
 627static int _ep_nuke(struct ci_hw_ep *hwep)
 628__releases(hwep->lock)
 629__acquires(hwep->lock)
 630{
 631	struct td_node *node, *tmpnode;
 632	if (hwep == NULL)
 633		return -EINVAL;
 634
 635	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
 636
 637	while (!list_empty(&hwep->qh.queue)) {
 638
 639		/* pop oldest request */
 640		struct ci_hw_req *hwreq = list_entry(hwep->qh.queue.next,
 641						     struct ci_hw_req, queue);
 642
 643		list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
 644			dma_pool_free(hwep->td_pool, node->ptr, node->dma);
 645			list_del_init(&node->td);
 646			node->ptr = NULL;
 647			kfree(node);
 648		}
 649
 650		list_del_init(&hwreq->queue);
 651		hwreq->req.status = -ESHUTDOWN;
 652
 653		if (hwreq->req.complete != NULL) {
 654			spin_unlock(hwep->lock);
 655			usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
 656			spin_lock(hwep->lock);
 657		}
 658	}
 659
 660	if (hwep->pending_td)
 661		free_pending_td(hwep);
 662
 663	return 0;
 664}
 665
 666static int _ep_set_halt(struct usb_ep *ep, int value, bool check_transfer)
 667{
 668	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
 669	int direction, retval = 0;
 670	unsigned long flags;
 671
 672	if (ep == NULL || hwep->ep.desc == NULL)
 673		return -EINVAL;
 674
 675	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
 676		return -EOPNOTSUPP;
 677
 678	spin_lock_irqsave(hwep->lock, flags);
 679
 680	if (value && hwep->dir == TX && check_transfer &&
 681		!list_empty(&hwep->qh.queue) &&
 682			!usb_endpoint_xfer_control(hwep->ep.desc)) {
 683		spin_unlock_irqrestore(hwep->lock, flags);
 684		return -EAGAIN;
 685	}
 686
 687	direction = hwep->dir;
 688	do {
 689		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
 690
 691		if (!value)
 692			hwep->wedge = 0;
 693
 694		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
 695			hwep->dir = (hwep->dir == TX) ? RX : TX;
 696
 697	} while (hwep->dir != direction);
 698
 699	spin_unlock_irqrestore(hwep->lock, flags);
 700	return retval;
 701}
 702
 703
 704/**
 705 * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
 706 * @gadget: gadget
 707 *
 708 * This function returns an error code
 709 */
 710static int _gadget_stop_activity(struct usb_gadget *gadget)
 711{
 712	struct usb_ep *ep;
 713	struct ci_hdrc    *ci = container_of(gadget, struct ci_hdrc, gadget);
 714	unsigned long flags;
 715
 716	spin_lock_irqsave(&ci->lock, flags);
 717	ci->gadget.speed = USB_SPEED_UNKNOWN;
 718	ci->remote_wakeup = 0;
 719	ci->suspended = 0;
 720	spin_unlock_irqrestore(&ci->lock, flags);
 721
 722	/* flush all endpoints */
 723	gadget_for_each_ep(ep, gadget) {
 724		usb_ep_fifo_flush(ep);
 725	}
 726	usb_ep_fifo_flush(&ci->ep0out->ep);
 727	usb_ep_fifo_flush(&ci->ep0in->ep);
 728
 729	/* make sure to disable all endpoints */
 730	gadget_for_each_ep(ep, gadget) {
 731		usb_ep_disable(ep);
 732	}
 733
 734	if (ci->status != NULL) {
 735		usb_ep_free_request(&ci->ep0in->ep, ci->status);
 736		ci->status = NULL;
 737	}
 738
 739	return 0;
 740}
 741
 742/******************************************************************************
 743 * ISR block
 744 *****************************************************************************/
 745/**
 746 * isr_reset_handler: USB reset interrupt handler
 747 * @ci: UDC device
 748 *
 749 * This function resets USB engine after a bus reset occurred
 750 */
 751static void isr_reset_handler(struct ci_hdrc *ci)
 752__releases(ci->lock)
 753__acquires(ci->lock)
 754{
 755	int retval;
 756
 757	spin_unlock(&ci->lock);
 758	if (ci->gadget.speed != USB_SPEED_UNKNOWN)
 759		usb_gadget_udc_reset(&ci->gadget, ci->driver);
 
 
 760
 761	retval = _gadget_stop_activity(&ci->gadget);
 762	if (retval)
 763		goto done;
 764
 765	retval = hw_usb_reset(ci);
 766	if (retval)
 767		goto done;
 768
 769	ci->status = usb_ep_alloc_request(&ci->ep0in->ep, GFP_ATOMIC);
 770	if (ci->status == NULL)
 771		retval = -ENOMEM;
 772
 773done:
 774	spin_lock(&ci->lock);
 775
 776	if (retval)
 777		dev_err(ci->dev, "error: %i\n", retval);
 778}
 779
 780/**
 781 * isr_get_status_complete: get_status request complete function
 782 * @ep:  endpoint
 783 * @req: request handled
 784 *
 785 * Caller must release lock
 786 */
 787static void isr_get_status_complete(struct usb_ep *ep, struct usb_request *req)
 788{
 789	if (ep == NULL || req == NULL)
 790		return;
 791
 792	kfree(req->buf);
 793	usb_ep_free_request(ep, req);
 794}
 795
 796/**
 797 * _ep_queue: queues (submits) an I/O request to an endpoint
 798 * @ep:        endpoint
 799 * @req:       request
 800 * @gfp_flags: GFP flags (not used)
 801 *
 802 * Caller must hold lock
 803 * This function returns an error code
 804 */
 805static int _ep_queue(struct usb_ep *ep, struct usb_request *req,
 806		    gfp_t __maybe_unused gfp_flags)
 807{
 808	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
 809	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
 810	struct ci_hdrc *ci = hwep->ci;
 811	int retval = 0;
 812
 813	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
 814		return -EINVAL;
 815
 816	if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
 817		if (req->length)
 818			hwep = (ci->ep0_dir == RX) ?
 819			       ci->ep0out : ci->ep0in;
 820		if (!list_empty(&hwep->qh.queue)) {
 821			_ep_nuke(hwep);
 
 822			dev_warn(hwep->ci->dev, "endpoint ctrl %X nuked\n",
 823				 _usb_addr(hwep));
 824		}
 825	}
 826
 827	if (usb_endpoint_xfer_isoc(hwep->ep.desc) &&
 828	    hwreq->req.length > (1 + hwep->ep.mult) * hwep->ep.maxpacket) {
 829		dev_err(hwep->ci->dev, "request length too big for isochronous\n");
 830		return -EMSGSIZE;
 831	}
 832
 833	/* first nuke then test link, e.g. previous status has not sent */
 834	if (!list_empty(&hwreq->queue)) {
 835		dev_err(hwep->ci->dev, "request already in queue\n");
 836		return -EBUSY;
 837	}
 838
 839	/* push request */
 840	hwreq->req.status = -EINPROGRESS;
 841	hwreq->req.actual = 0;
 842
 843	retval = _hardware_enqueue(hwep, hwreq);
 844
 845	if (retval == -EALREADY)
 846		retval = 0;
 847	if (!retval)
 848		list_add_tail(&hwreq->queue, &hwep->qh.queue);
 849
 850	return retval;
 851}
 852
 853/**
 854 * isr_get_status_response: get_status request response
 855 * @ci: ci struct
 856 * @setup: setup request packet
 857 *
 858 * This function returns an error code
 859 */
 860static int isr_get_status_response(struct ci_hdrc *ci,
 861				   struct usb_ctrlrequest *setup)
 862__releases(hwep->lock)
 863__acquires(hwep->lock)
 864{
 865	struct ci_hw_ep *hwep = ci->ep0in;
 866	struct usb_request *req = NULL;
 867	gfp_t gfp_flags = GFP_ATOMIC;
 868	int dir, num, retval;
 869
 870	if (hwep == NULL || setup == NULL)
 871		return -EINVAL;
 872
 873	spin_unlock(hwep->lock);
 874	req = usb_ep_alloc_request(&hwep->ep, gfp_flags);
 875	spin_lock(hwep->lock);
 876	if (req == NULL)
 877		return -ENOMEM;
 878
 879	req->complete = isr_get_status_complete;
 880	req->length   = 2;
 881	req->buf      = kzalloc(req->length, gfp_flags);
 882	if (req->buf == NULL) {
 883		retval = -ENOMEM;
 884		goto err_free_req;
 885	}
 886
 887	if ((setup->bRequestType & USB_RECIP_MASK) == USB_RECIP_DEVICE) {
 888		*(u16 *)req->buf = (ci->remote_wakeup << 1) |
 889			ci->gadget.is_selfpowered;
 
 890	} else if ((setup->bRequestType & USB_RECIP_MASK) \
 891		   == USB_RECIP_ENDPOINT) {
 892		dir = (le16_to_cpu(setup->wIndex) & USB_ENDPOINT_DIR_MASK) ?
 893			TX : RX;
 894		num =  le16_to_cpu(setup->wIndex) & USB_ENDPOINT_NUMBER_MASK;
 895		*(u16 *)req->buf = hw_ep_get_halt(ci, num, dir);
 896	}
 897	/* else do nothing; reserved for future use */
 898
 899	retval = _ep_queue(&hwep->ep, req, gfp_flags);
 900	if (retval)
 901		goto err_free_buf;
 902
 903	return 0;
 904
 905 err_free_buf:
 906	kfree(req->buf);
 907 err_free_req:
 908	spin_unlock(hwep->lock);
 909	usb_ep_free_request(&hwep->ep, req);
 910	spin_lock(hwep->lock);
 911	return retval;
 912}
 913
 914/**
 915 * isr_setup_status_complete: setup_status request complete function
 916 * @ep:  endpoint
 917 * @req: request handled
 918 *
 919 * Caller must release lock. Put the port in test mode if test mode
 920 * feature is selected.
 921 */
 922static void
 923isr_setup_status_complete(struct usb_ep *ep, struct usb_request *req)
 924{
 925	struct ci_hdrc *ci = req->context;
 926	unsigned long flags;
 927
 928	if (ci->setaddr) {
 929		hw_usb_set_address(ci, ci->address);
 930		ci->setaddr = false;
 931		if (ci->address)
 932			usb_gadget_set_state(&ci->gadget, USB_STATE_ADDRESS);
 933	}
 934
 935	spin_lock_irqsave(&ci->lock, flags);
 936	if (ci->test_mode)
 937		hw_port_test_set(ci, ci->test_mode);
 938	spin_unlock_irqrestore(&ci->lock, flags);
 939}
 940
 941/**
 942 * isr_setup_status_phase: queues the status phase of a setup transation
 943 * @ci: ci struct
 944 *
 945 * This function returns an error code
 946 */
 947static int isr_setup_status_phase(struct ci_hdrc *ci)
 948{
 949	int retval;
 950	struct ci_hw_ep *hwep;
 951
 952	hwep = (ci->ep0_dir == TX) ? ci->ep0out : ci->ep0in;
 953	ci->status->context = ci;
 954	ci->status->complete = isr_setup_status_complete;
 955
 956	retval = _ep_queue(&hwep->ep, ci->status, GFP_ATOMIC);
 957
 958	return retval;
 959}
 960
 961/**
 962 * isr_tr_complete_low: transaction complete low level handler
 963 * @hwep: endpoint
 964 *
 965 * This function returns an error code
 966 * Caller must hold lock
 967 */
 968static int isr_tr_complete_low(struct ci_hw_ep *hwep)
 969__releases(hwep->lock)
 970__acquires(hwep->lock)
 971{
 972	struct ci_hw_req *hwreq, *hwreqtemp;
 973	struct ci_hw_ep *hweptemp = hwep;
 974	int retval = 0;
 975
 976	list_for_each_entry_safe(hwreq, hwreqtemp, &hwep->qh.queue,
 977			queue) {
 978		retval = _hardware_dequeue(hwep, hwreq);
 979		if (retval < 0)
 980			break;
 981		list_del_init(&hwreq->queue);
 982		if (hwreq->req.complete != NULL) {
 983			spin_unlock(hwep->lock);
 984			if ((hwep->type == USB_ENDPOINT_XFER_CONTROL) &&
 985					hwreq->req.length)
 986				hweptemp = hwep->ci->ep0in;
 987			usb_gadget_giveback_request(&hweptemp->ep, &hwreq->req);
 988			spin_lock(hwep->lock);
 989		}
 990	}
 991
 992	if (retval == -EBUSY)
 993		retval = 0;
 994
 995	return retval;
 996}
 997
 998static int otg_a_alt_hnp_support(struct ci_hdrc *ci)
 999{
1000	dev_warn(&ci->gadget.dev,
1001		"connect the device to an alternate port if you want HNP\n");
1002	return isr_setup_status_phase(ci);
1003}
1004
1005/**
1006 * isr_setup_packet_handler: setup packet handler
1007 * @ci: UDC descriptor
1008 *
1009 * This function handles setup packet 
1010 */
1011static void isr_setup_packet_handler(struct ci_hdrc *ci)
1012__releases(ci->lock)
1013__acquires(ci->lock)
1014{
1015	struct ci_hw_ep *hwep = &ci->ci_hw_ep[0];
1016	struct usb_ctrlrequest req;
1017	int type, num, dir, err = -EINVAL;
1018	u8 tmode = 0;
1019
1020	/*
1021	 * Flush data and handshake transactions of previous
1022	 * setup packet.
1023	 */
1024	_ep_nuke(ci->ep0out);
1025	_ep_nuke(ci->ep0in);
1026
1027	/* read_setup_packet */
1028	do {
1029		hw_test_and_set_setup_guard(ci);
1030		memcpy(&req, &hwep->qh.ptr->setup, sizeof(req));
1031	} while (!hw_test_and_clear_setup_guard(ci));
1032
1033	type = req.bRequestType;
1034
1035	ci->ep0_dir = (type & USB_DIR_IN) ? TX : RX;
1036
1037	switch (req.bRequest) {
1038	case USB_REQ_CLEAR_FEATURE:
1039		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1040				le16_to_cpu(req.wValue) ==
1041				USB_ENDPOINT_HALT) {
1042			if (req.wLength != 0)
1043				break;
1044			num  = le16_to_cpu(req.wIndex);
1045			dir = num & USB_ENDPOINT_DIR_MASK;
1046			num &= USB_ENDPOINT_NUMBER_MASK;
1047			if (dir) /* TX */
1048				num += ci->hw_ep_max / 2;
1049			if (!ci->ci_hw_ep[num].wedge) {
1050				spin_unlock(&ci->lock);
1051				err = usb_ep_clear_halt(
1052					&ci->ci_hw_ep[num].ep);
1053				spin_lock(&ci->lock);
1054				if (err)
1055					break;
1056			}
1057			err = isr_setup_status_phase(ci);
1058		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE) &&
1059				le16_to_cpu(req.wValue) ==
1060				USB_DEVICE_REMOTE_WAKEUP) {
1061			if (req.wLength != 0)
1062				break;
1063			ci->remote_wakeup = 0;
1064			err = isr_setup_status_phase(ci);
1065		} else {
1066			goto delegate;
1067		}
1068		break;
1069	case USB_REQ_GET_STATUS:
1070		if ((type != (USB_DIR_IN|USB_RECIP_DEVICE) ||
1071			le16_to_cpu(req.wIndex) == OTG_STS_SELECTOR) &&
1072		    type != (USB_DIR_IN|USB_RECIP_ENDPOINT) &&
1073		    type != (USB_DIR_IN|USB_RECIP_INTERFACE))
1074			goto delegate;
1075		if (le16_to_cpu(req.wLength) != 2 ||
1076		    le16_to_cpu(req.wValue)  != 0)
1077			break;
1078		err = isr_get_status_response(ci, &req);
1079		break;
1080	case USB_REQ_SET_ADDRESS:
1081		if (type != (USB_DIR_OUT|USB_RECIP_DEVICE))
1082			goto delegate;
1083		if (le16_to_cpu(req.wLength) != 0 ||
1084		    le16_to_cpu(req.wIndex)  != 0)
1085			break;
1086		ci->address = (u8)le16_to_cpu(req.wValue);
1087		ci->setaddr = true;
1088		err = isr_setup_status_phase(ci);
1089		break;
1090	case USB_REQ_SET_FEATURE:
1091		if (type == (USB_DIR_OUT|USB_RECIP_ENDPOINT) &&
1092				le16_to_cpu(req.wValue) ==
1093				USB_ENDPOINT_HALT) {
1094			if (req.wLength != 0)
1095				break;
1096			num  = le16_to_cpu(req.wIndex);
1097			dir = num & USB_ENDPOINT_DIR_MASK;
1098			num &= USB_ENDPOINT_NUMBER_MASK;
1099			if (dir) /* TX */
1100				num += ci->hw_ep_max / 2;
1101
1102			spin_unlock(&ci->lock);
1103			err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
1104			spin_lock(&ci->lock);
1105			if (!err)
1106				isr_setup_status_phase(ci);
1107		} else if (type == (USB_DIR_OUT|USB_RECIP_DEVICE)) {
1108			if (req.wLength != 0)
1109				break;
1110			switch (le16_to_cpu(req.wValue)) {
1111			case USB_DEVICE_REMOTE_WAKEUP:
1112				ci->remote_wakeup = 1;
1113				err = isr_setup_status_phase(ci);
1114				break;
1115			case USB_DEVICE_TEST_MODE:
1116				tmode = le16_to_cpu(req.wIndex) >> 8;
1117				switch (tmode) {
1118				case TEST_J:
1119				case TEST_K:
1120				case TEST_SE0_NAK:
1121				case TEST_PACKET:
1122				case TEST_FORCE_EN:
1123					ci->test_mode = tmode;
1124					err = isr_setup_status_phase(
1125							ci);
1126					break;
1127				default:
1128					break;
1129				}
1130				break;
1131			case USB_DEVICE_B_HNP_ENABLE:
1132				if (ci_otg_is_fsm_mode(ci)) {
1133					ci->gadget.b_hnp_enable = 1;
1134					err = isr_setup_status_phase(
1135							ci);
1136				}
1137				break;
1138			case USB_DEVICE_A_ALT_HNP_SUPPORT:
1139				if (ci_otg_is_fsm_mode(ci))
1140					err = otg_a_alt_hnp_support(ci);
1141				break;
1142			case USB_DEVICE_A_HNP_SUPPORT:
1143				if (ci_otg_is_fsm_mode(ci)) {
1144					ci->gadget.a_hnp_support = 1;
1145					err = isr_setup_status_phase(
1146							ci);
1147				}
1148				break;
1149			default:
1150				goto delegate;
1151			}
1152		} else {
1153			goto delegate;
1154		}
1155		break;
1156	default:
1157delegate:
1158		if (req.wLength == 0)   /* no data phase */
1159			ci->ep0_dir = TX;
1160
1161		spin_unlock(&ci->lock);
1162		err = ci->driver->setup(&ci->gadget, &req);
1163		spin_lock(&ci->lock);
1164		break;
1165	}
1166
1167	if (err < 0) {
1168		spin_unlock(&ci->lock);
1169		if (_ep_set_halt(&hwep->ep, 1, false))
1170			dev_err(ci->dev, "error: _ep_set_halt\n");
1171		spin_lock(&ci->lock);
1172	}
1173}
1174
1175/**
1176 * isr_tr_complete_handler: transaction complete interrupt handler
1177 * @ci: UDC descriptor
1178 *
1179 * This function handles traffic events
1180 */
1181static void isr_tr_complete_handler(struct ci_hdrc *ci)
1182__releases(ci->lock)
1183__acquires(ci->lock)
1184{
1185	unsigned i;
1186	int err;
1187
1188	for (i = 0; i < ci->hw_ep_max; i++) {
1189		struct ci_hw_ep *hwep  = &ci->ci_hw_ep[i];
1190
1191		if (hwep->ep.desc == NULL)
1192			continue;   /* not configured */
1193
1194		if (hw_test_and_clear_complete(ci, i)) {
1195			err = isr_tr_complete_low(hwep);
1196			if (hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1197				if (err > 0)   /* needs status phase */
1198					err = isr_setup_status_phase(ci);
1199				if (err < 0) {
1200					spin_unlock(&ci->lock);
1201					if (_ep_set_halt(&hwep->ep, 1, false))
1202						dev_err(ci->dev,
1203						"error: _ep_set_halt\n");
1204					spin_lock(&ci->lock);
1205				}
1206			}
1207		}
1208
1209		/* Only handle setup packet below */
1210		if (i == 0 &&
1211			hw_test_and_clear(ci, OP_ENDPTSETUPSTAT, BIT(0)))
1212			isr_setup_packet_handler(ci);
1213	}
1214}
1215
1216/******************************************************************************
1217 * ENDPT block
1218 *****************************************************************************/
1219/**
1220 * ep_enable: configure endpoint, making it usable
1221 *
1222 * Check usb_ep_enable() at "usb_gadget.h" for details
1223 */
1224static int ep_enable(struct usb_ep *ep,
1225		     const struct usb_endpoint_descriptor *desc)
1226{
1227	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1228	int retval = 0;
1229	unsigned long flags;
1230	u32 cap = 0;
1231
1232	if (ep == NULL || desc == NULL)
1233		return -EINVAL;
1234
1235	spin_lock_irqsave(hwep->lock, flags);
1236
1237	/* only internal SW should enable ctrl endpts */
1238
1239	if (!list_empty(&hwep->qh.queue)) {
1240		dev_warn(hwep->ci->dev, "enabling a non-empty endpoint!\n");
1241		spin_unlock_irqrestore(hwep->lock, flags);
1242		return -EBUSY;
1243	}
1244
1245	hwep->ep.desc = desc;
1246
 
 
 
1247	hwep->dir  = usb_endpoint_dir_in(desc) ? TX : RX;
1248	hwep->num  = usb_endpoint_num(desc);
1249	hwep->type = usb_endpoint_type(desc);
1250
1251	hwep->ep.maxpacket = usb_endpoint_maxp(desc) & 0x07ff;
1252	hwep->ep.mult = QH_ISO_MULT(usb_endpoint_maxp(desc));
1253
1254	if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1255		cap |= QH_IOS;
1256
1257	cap |= QH_ZLT;
1258	cap |= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
1259	/*
1260	 * For ISO-TX, we set mult at QH as the largest value, and use
1261	 * MultO at TD as real mult value.
1262	 */
1263	if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
1264		cap |= 3 << __ffs(QH_MULT);
1265
1266	hwep->qh.ptr->cap = cpu_to_le32(cap);
1267
1268	hwep->qh.ptr->td.next |= cpu_to_le32(TD_TERMINATE);   /* needed? */
1269
1270	if (hwep->num != 0 && hwep->type == USB_ENDPOINT_XFER_CONTROL) {
1271		dev_err(hwep->ci->dev, "Set control xfer at non-ep0\n");
1272		retval = -EINVAL;
1273	}
1274
1275	/*
1276	 * Enable endpoints in the HW other than ep0 as ep0
1277	 * is always enabled
1278	 */
1279	if (hwep->num)
1280		retval |= hw_ep_enable(hwep->ci, hwep->num, hwep->dir,
1281				       hwep->type);
1282
1283	spin_unlock_irqrestore(hwep->lock, flags);
1284	return retval;
1285}
1286
1287/**
1288 * ep_disable: endpoint is no longer usable
1289 *
1290 * Check usb_ep_disable() at "usb_gadget.h" for details
1291 */
1292static int ep_disable(struct usb_ep *ep)
1293{
1294	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1295	int direction, retval = 0;
1296	unsigned long flags;
1297
1298	if (ep == NULL)
1299		return -EINVAL;
1300	else if (hwep->ep.desc == NULL)
1301		return -EBUSY;
1302
1303	spin_lock_irqsave(hwep->lock, flags);
1304
1305	/* only internal SW should disable ctrl endpts */
1306
1307	direction = hwep->dir;
1308	do {
1309		retval |= _ep_nuke(hwep);
1310		retval |= hw_ep_disable(hwep->ci, hwep->num, hwep->dir);
1311
1312		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
1313			hwep->dir = (hwep->dir == TX) ? RX : TX;
1314
1315	} while (hwep->dir != direction);
1316
1317	hwep->ep.desc = NULL;
1318
1319	spin_unlock_irqrestore(hwep->lock, flags);
1320	return retval;
1321}
1322
1323/**
1324 * ep_alloc_request: allocate a request object to use with this endpoint
1325 *
1326 * Check usb_ep_alloc_request() at "usb_gadget.h" for details
1327 */
1328static struct usb_request *ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
1329{
1330	struct ci_hw_req *hwreq = NULL;
1331
1332	if (ep == NULL)
1333		return NULL;
1334
1335	hwreq = kzalloc(sizeof(struct ci_hw_req), gfp_flags);
1336	if (hwreq != NULL) {
1337		INIT_LIST_HEAD(&hwreq->queue);
1338		INIT_LIST_HEAD(&hwreq->tds);
1339	}
1340
1341	return (hwreq == NULL) ? NULL : &hwreq->req;
1342}
1343
1344/**
1345 * ep_free_request: frees a request object
1346 *
1347 * Check usb_ep_free_request() at "usb_gadget.h" for details
1348 */
1349static void ep_free_request(struct usb_ep *ep, struct usb_request *req)
1350{
1351	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1352	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1353	struct td_node *node, *tmpnode;
1354	unsigned long flags;
1355
1356	if (ep == NULL || req == NULL) {
1357		return;
1358	} else if (!list_empty(&hwreq->queue)) {
1359		dev_err(hwep->ci->dev, "freeing queued request\n");
1360		return;
1361	}
1362
1363	spin_lock_irqsave(hwep->lock, flags);
1364
1365	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1366		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1367		list_del_init(&node->td);
1368		node->ptr = NULL;
1369		kfree(node);
1370	}
1371
1372	kfree(hwreq);
1373
1374	spin_unlock_irqrestore(hwep->lock, flags);
1375}
1376
1377/**
1378 * ep_queue: queues (submits) an I/O request to an endpoint
1379 *
1380 * Check usb_ep_queue()* at usb_gadget.h" for details
1381 */
1382static int ep_queue(struct usb_ep *ep, struct usb_request *req,
1383		    gfp_t __maybe_unused gfp_flags)
1384{
1385	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1386	int retval = 0;
1387	unsigned long flags;
1388
1389	if (ep == NULL || req == NULL || hwep->ep.desc == NULL)
1390		return -EINVAL;
1391
1392	spin_lock_irqsave(hwep->lock, flags);
1393	retval = _ep_queue(ep, req, gfp_flags);
1394	spin_unlock_irqrestore(hwep->lock, flags);
1395	return retval;
1396}
1397
1398/**
1399 * ep_dequeue: dequeues (cancels, unlinks) an I/O request from an endpoint
1400 *
1401 * Check usb_ep_dequeue() at "usb_gadget.h" for details
1402 */
1403static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
1404{
1405	struct ci_hw_ep  *hwep  = container_of(ep,  struct ci_hw_ep, ep);
1406	struct ci_hw_req *hwreq = container_of(req, struct ci_hw_req, req);
1407	unsigned long flags;
1408	struct td_node *node, *tmpnode;
1409
1410	if (ep == NULL || req == NULL || hwreq->req.status != -EALREADY ||
1411		hwep->ep.desc == NULL || list_empty(&hwreq->queue) ||
1412		list_empty(&hwep->qh.queue))
1413		return -EINVAL;
1414
1415	spin_lock_irqsave(hwep->lock, flags);
1416
1417	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1418
1419	list_for_each_entry_safe(node, tmpnode, &hwreq->tds, td) {
1420		dma_pool_free(hwep->td_pool, node->ptr, node->dma);
1421		list_del(&node->td);
1422		kfree(node);
1423	}
1424
1425	/* pop request */
1426	list_del_init(&hwreq->queue);
1427
1428	usb_gadget_unmap_request(&hwep->ci->gadget, req, hwep->dir);
1429
1430	req->status = -ECONNRESET;
1431
1432	if (hwreq->req.complete != NULL) {
1433		spin_unlock(hwep->lock);
1434		usb_gadget_giveback_request(&hwep->ep, &hwreq->req);
1435		spin_lock(hwep->lock);
1436	}
1437
1438	spin_unlock_irqrestore(hwep->lock, flags);
1439	return 0;
1440}
1441
1442/**
1443 * ep_set_halt: sets the endpoint halt feature
1444 *
1445 * Check usb_ep_set_halt() at "usb_gadget.h" for details
1446 */
1447static int ep_set_halt(struct usb_ep *ep, int value)
1448{
1449	return _ep_set_halt(ep, value, true);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1450}
1451
1452/**
1453 * ep_set_wedge: sets the halt feature and ignores clear requests
1454 *
1455 * Check usb_ep_set_wedge() at "usb_gadget.h" for details
1456 */
1457static int ep_set_wedge(struct usb_ep *ep)
1458{
1459	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1460	unsigned long flags;
1461
1462	if (ep == NULL || hwep->ep.desc == NULL)
1463		return -EINVAL;
1464
1465	spin_lock_irqsave(hwep->lock, flags);
1466	hwep->wedge = 1;
1467	spin_unlock_irqrestore(hwep->lock, flags);
1468
1469	return usb_ep_set_halt(ep);
1470}
1471
1472/**
1473 * ep_fifo_flush: flushes contents of a fifo
1474 *
1475 * Check usb_ep_fifo_flush() at "usb_gadget.h" for details
1476 */
1477static void ep_fifo_flush(struct usb_ep *ep)
1478{
1479	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
1480	unsigned long flags;
1481
1482	if (ep == NULL) {
1483		dev_err(hwep->ci->dev, "%02X: -EINVAL\n", _usb_addr(hwep));
1484		return;
1485	}
1486
1487	spin_lock_irqsave(hwep->lock, flags);
1488
1489	hw_ep_flush(hwep->ci, hwep->num, hwep->dir);
1490
1491	spin_unlock_irqrestore(hwep->lock, flags);
1492}
1493
1494/**
1495 * Endpoint-specific part of the API to the USB controller hardware
1496 * Check "usb_gadget.h" for details
1497 */
1498static const struct usb_ep_ops usb_ep_ops = {
1499	.enable	       = ep_enable,
1500	.disable       = ep_disable,
1501	.alloc_request = ep_alloc_request,
1502	.free_request  = ep_free_request,
1503	.queue	       = ep_queue,
1504	.dequeue       = ep_dequeue,
1505	.set_halt      = ep_set_halt,
1506	.set_wedge     = ep_set_wedge,
1507	.fifo_flush    = ep_fifo_flush,
1508};
1509
1510/******************************************************************************
1511 * GADGET block
1512 *****************************************************************************/
1513static int ci_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1514{
1515	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1516	unsigned long flags;
1517	int gadget_ready = 0;
1518
1519	spin_lock_irqsave(&ci->lock, flags);
1520	ci->vbus_active = is_active;
1521	if (ci->driver)
1522		gadget_ready = 1;
1523	spin_unlock_irqrestore(&ci->lock, flags);
1524
1525	if (gadget_ready) {
1526		if (is_active) {
1527			pm_runtime_get_sync(&_gadget->dev);
1528			hw_device_reset(ci);
1529			hw_device_state(ci, ci->ep0out->qh.dma);
1530			usb_gadget_set_state(_gadget, USB_STATE_POWERED);
1531			usb_udc_vbus_handler(_gadget, true);
1532		} else {
1533			usb_udc_vbus_handler(_gadget, false);
1534			if (ci->driver)
1535				ci->driver->disconnect(&ci->gadget);
1536			hw_device_state(ci, 0);
1537			if (ci->platdata->notify_event)
1538				ci->platdata->notify_event(ci,
1539				CI_HDRC_CONTROLLER_STOPPED_EVENT);
1540			_gadget_stop_activity(&ci->gadget);
1541			pm_runtime_put_sync(&_gadget->dev);
1542			usb_gadget_set_state(_gadget, USB_STATE_NOTATTACHED);
1543		}
1544	}
1545
1546	return 0;
1547}
1548
1549static int ci_udc_wakeup(struct usb_gadget *_gadget)
1550{
1551	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1552	unsigned long flags;
1553	int ret = 0;
1554
1555	spin_lock_irqsave(&ci->lock, flags);
1556	if (!ci->remote_wakeup) {
1557		ret = -EOPNOTSUPP;
1558		goto out;
1559	}
1560	if (!hw_read(ci, OP_PORTSC, PORTSC_SUSP)) {
1561		ret = -EINVAL;
1562		goto out;
1563	}
1564	hw_write(ci, OP_PORTSC, PORTSC_FPR, PORTSC_FPR);
1565out:
1566	spin_unlock_irqrestore(&ci->lock, flags);
1567	return ret;
1568}
1569
1570static int ci_udc_vbus_draw(struct usb_gadget *_gadget, unsigned ma)
1571{
1572	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1573
1574	if (ci->usb_phy)
1575		return usb_phy_set_power(ci->usb_phy, ma);
1576	return -ENOTSUPP;
1577}
1578
1579static int ci_udc_selfpowered(struct usb_gadget *_gadget, int is_on)
1580{
1581	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1582	struct ci_hw_ep *hwep = ci->ep0in;
1583	unsigned long flags;
1584
1585	spin_lock_irqsave(hwep->lock, flags);
1586	_gadget->is_selfpowered = (is_on != 0);
1587	spin_unlock_irqrestore(hwep->lock, flags);
1588
1589	return 0;
1590}
1591
1592/* Change Data+ pullup status
1593 * this func is used by usb_gadget_connect/disconnet
1594 */
1595static int ci_udc_pullup(struct usb_gadget *_gadget, int is_on)
1596{
1597	struct ci_hdrc *ci = container_of(_gadget, struct ci_hdrc, gadget);
1598
1599	/* Data+ pullup controlled by OTG state machine in OTG fsm mode */
1600	if (ci_otg_is_fsm_mode(ci))
1601		return 0;
1602
1603	pm_runtime_get_sync(&ci->gadget.dev);
1604	if (is_on)
1605		hw_write(ci, OP_USBCMD, USBCMD_RS, USBCMD_RS);
1606	else
1607		hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
1608	pm_runtime_put_sync(&ci->gadget.dev);
1609
1610	return 0;
1611}
1612
1613static int ci_udc_start(struct usb_gadget *gadget,
1614			 struct usb_gadget_driver *driver);
1615static int ci_udc_stop(struct usb_gadget *gadget);
 
1616/**
1617 * Device operations part of the API to the USB controller hardware,
1618 * which don't involve endpoints (or i/o)
1619 * Check  "usb_gadget.h" for details
1620 */
1621static const struct usb_gadget_ops usb_gadget_ops = {
1622	.vbus_session	= ci_udc_vbus_session,
1623	.wakeup		= ci_udc_wakeup,
1624	.set_selfpowered	= ci_udc_selfpowered,
1625	.pullup		= ci_udc_pullup,
1626	.vbus_draw	= ci_udc_vbus_draw,
1627	.udc_start	= ci_udc_start,
1628	.udc_stop	= ci_udc_stop,
1629};
1630
1631static int init_eps(struct ci_hdrc *ci)
1632{
1633	int retval = 0, i, j;
1634
1635	for (i = 0; i < ci->hw_ep_max/2; i++)
1636		for (j = RX; j <= TX; j++) {
1637			int k = i + j * ci->hw_ep_max/2;
1638			struct ci_hw_ep *hwep = &ci->ci_hw_ep[k];
1639
1640			scnprintf(hwep->name, sizeof(hwep->name), "ep%i%s", i,
1641					(j == TX)  ? "in" : "out");
1642
1643			hwep->ci          = ci;
1644			hwep->lock         = &ci->lock;
1645			hwep->td_pool      = ci->td_pool;
1646
1647			hwep->ep.name      = hwep->name;
1648			hwep->ep.ops       = &usb_ep_ops;
1649
1650			if (i == 0) {
1651				hwep->ep.caps.type_control = true;
1652			} else {
1653				hwep->ep.caps.type_iso = true;
1654				hwep->ep.caps.type_bulk = true;
1655				hwep->ep.caps.type_int = true;
1656			}
1657
1658			if (j == TX)
1659				hwep->ep.caps.dir_in = true;
1660			else
1661				hwep->ep.caps.dir_out = true;
1662
1663			/*
1664			 * for ep0: maxP defined in desc, for other
1665			 * eps, maxP is set by epautoconfig() called
1666			 * by gadget layer
1667			 */
1668			usb_ep_set_maxpacket_limit(&hwep->ep, (unsigned short)~0);
1669
1670			INIT_LIST_HEAD(&hwep->qh.queue);
1671			hwep->qh.ptr = dma_pool_alloc(ci->qh_pool, GFP_KERNEL,
1672						     &hwep->qh.dma);
1673			if (hwep->qh.ptr == NULL)
1674				retval = -ENOMEM;
1675			else
1676				memset(hwep->qh.ptr, 0, sizeof(*hwep->qh.ptr));
1677
1678			/*
1679			 * set up shorthands for ep0 out and in endpoints,
1680			 * don't add to gadget's ep_list
1681			 */
1682			if (i == 0) {
1683				if (j == RX)
1684					ci->ep0out = hwep;
1685				else
1686					ci->ep0in = hwep;
1687
1688				usb_ep_set_maxpacket_limit(&hwep->ep, CTRL_PAYLOAD_MAX);
1689				continue;
1690			}
1691
1692			list_add_tail(&hwep->ep.ep_list, &ci->gadget.ep_list);
1693		}
1694
1695	return retval;
1696}
1697
1698static void destroy_eps(struct ci_hdrc *ci)
1699{
1700	int i;
1701
1702	for (i = 0; i < ci->hw_ep_max; i++) {
1703		struct ci_hw_ep *hwep = &ci->ci_hw_ep[i];
1704
1705		if (hwep->pending_td)
1706			free_pending_td(hwep);
1707		dma_pool_free(ci->qh_pool, hwep->qh.ptr, hwep->qh.dma);
1708	}
1709}
1710
1711/**
1712 * ci_udc_start: register a gadget driver
1713 * @gadget: our gadget
1714 * @driver: the driver being registered
1715 *
1716 * Interrupts are enabled here.
1717 */
1718static int ci_udc_start(struct usb_gadget *gadget,
1719			 struct usb_gadget_driver *driver)
1720{
1721	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1722	unsigned long flags;
1723	int retval = -ENOMEM;
1724
1725	if (driver->disconnect == NULL)
1726		return -EINVAL;
1727
1728
1729	ci->ep0out->ep.desc = &ctrl_endpt_out_desc;
1730	retval = usb_ep_enable(&ci->ep0out->ep);
1731	if (retval)
1732		return retval;
1733
1734	ci->ep0in->ep.desc = &ctrl_endpt_in_desc;
1735	retval = usb_ep_enable(&ci->ep0in->ep);
1736	if (retval)
1737		return retval;
1738
1739	ci->driver = driver;
1740
1741	/* Start otg fsm for B-device */
1742	if (ci_otg_is_fsm_mode(ci) && ci->fsm.id) {
1743		ci_hdrc_otg_fsm_start(ci);
1744		return retval;
1745	}
1746
1747	pm_runtime_get_sync(&ci->gadget.dev);
1748	if (ci->vbus_active) {
1749		spin_lock_irqsave(&ci->lock, flags);
1750		hw_device_reset(ci);
1751	} else {
1752		usb_udc_vbus_handler(&ci->gadget, false);
1753		pm_runtime_put_sync(&ci->gadget.dev);
1754		return retval;
1755	}
1756
1757	retval = hw_device_state(ci, ci->ep0out->qh.dma);
1758	spin_unlock_irqrestore(&ci->lock, flags);
1759	if (retval)
1760		pm_runtime_put_sync(&ci->gadget.dev);
1761
1762	return retval;
1763}
1764
1765static void ci_udc_stop_for_otg_fsm(struct ci_hdrc *ci)
1766{
1767	if (!ci_otg_is_fsm_mode(ci))
1768		return;
1769
1770	mutex_lock(&ci->fsm.lock);
1771	if (ci->fsm.otg->state == OTG_STATE_A_PERIPHERAL) {
1772		ci->fsm.a_bidl_adis_tmout = 1;
1773		ci_hdrc_otg_fsm_start(ci);
1774	} else if (ci->fsm.otg->state == OTG_STATE_B_PERIPHERAL) {
1775		ci->fsm.protocol = PROTO_UNDEF;
1776		ci->fsm.otg->state = OTG_STATE_UNDEFINED;
1777	}
1778	mutex_unlock(&ci->fsm.lock);
1779}
1780
1781/**
1782 * ci_udc_stop: unregister a gadget driver
1783 */
1784static int ci_udc_stop(struct usb_gadget *gadget)
 
1785{
1786	struct ci_hdrc *ci = container_of(gadget, struct ci_hdrc, gadget);
1787	unsigned long flags;
1788
1789	spin_lock_irqsave(&ci->lock, flags);
1790
1791	if (ci->vbus_active) {
1792		hw_device_state(ci, 0);
1793		if (ci->platdata->notify_event)
1794			ci->platdata->notify_event(ci,
1795			CI_HDRC_CONTROLLER_STOPPED_EVENT);
1796		spin_unlock_irqrestore(&ci->lock, flags);
1797		_gadget_stop_activity(&ci->gadget);
1798		spin_lock_irqsave(&ci->lock, flags);
1799		pm_runtime_put(&ci->gadget.dev);
1800	}
1801
1802	ci->driver = NULL;
1803	spin_unlock_irqrestore(&ci->lock, flags);
1804
1805	ci_udc_stop_for_otg_fsm(ci);
1806	return 0;
1807}
1808
1809/******************************************************************************
1810 * BUS block
1811 *****************************************************************************/
1812/**
1813 * udc_irq: ci interrupt handler
1814 *
1815 * This function returns IRQ_HANDLED if the IRQ has been handled
1816 * It locks access to registers
1817 */
1818static irqreturn_t udc_irq(struct ci_hdrc *ci)
1819{
1820	irqreturn_t retval;
1821	u32 intr;
1822
1823	if (ci == NULL)
1824		return IRQ_HANDLED;
1825
1826	spin_lock(&ci->lock);
1827
1828	if (ci->platdata->flags & CI_HDRC_REGS_SHARED) {
1829		if (hw_read(ci, OP_USBMODE, USBMODE_CM) !=
1830				USBMODE_CM_DC) {
1831			spin_unlock(&ci->lock);
1832			return IRQ_NONE;
1833		}
1834	}
1835	intr = hw_test_and_clear_intr_active(ci);
1836
1837	if (intr) {
1838		/* order defines priority - do NOT change it */
1839		if (USBi_URI & intr)
1840			isr_reset_handler(ci);
1841
1842		if (USBi_PCI & intr) {
1843			ci->gadget.speed = hw_port_is_high_speed(ci) ?
1844				USB_SPEED_HIGH : USB_SPEED_FULL;
1845			if (ci->suspended && ci->driver->resume) {
1846				spin_unlock(&ci->lock);
1847				ci->driver->resume(&ci->gadget);
1848				spin_lock(&ci->lock);
1849				ci->suspended = 0;
1850			}
1851		}
1852
1853		if (USBi_UI  & intr)
1854			isr_tr_complete_handler(ci);
1855
1856		if (USBi_SLI & intr) {
1857			if (ci->gadget.speed != USB_SPEED_UNKNOWN &&
1858			    ci->driver->suspend) {
1859				ci->suspended = 1;
1860				spin_unlock(&ci->lock);
1861				ci->driver->suspend(&ci->gadget);
1862				usb_gadget_set_state(&ci->gadget,
1863						USB_STATE_SUSPENDED);
1864				spin_lock(&ci->lock);
1865			}
1866		}
1867		retval = IRQ_HANDLED;
1868	} else {
1869		retval = IRQ_NONE;
1870	}
1871	spin_unlock(&ci->lock);
1872
1873	return retval;
1874}
1875
1876/**
1877 * udc_start: initialize gadget role
1878 * @ci: chipidea controller
1879 */
1880static int udc_start(struct ci_hdrc *ci)
1881{
1882	struct device *dev = ci->dev;
1883	struct usb_otg_caps *otg_caps = &ci->platdata->ci_otg_caps;
1884	int retval = 0;
1885
1886	spin_lock_init(&ci->lock);
1887
1888	ci->gadget.ops          = &usb_gadget_ops;
1889	ci->gadget.speed        = USB_SPEED_UNKNOWN;
1890	ci->gadget.max_speed    = USB_SPEED_HIGH;
 
1891	ci->gadget.name         = ci->platdata->name;
1892	ci->gadget.otg_caps	= otg_caps;
1893
1894	if (ci->is_otg && (otg_caps->hnp_support || otg_caps->srp_support ||
1895						otg_caps->adp_support))
1896		ci->gadget.is_otg = 1;
1897
1898	INIT_LIST_HEAD(&ci->gadget.ep_list);
1899
1900	/* alloc resources */
1901	ci->qh_pool = dma_pool_create("ci_hw_qh", dev,
1902				       sizeof(struct ci_hw_qh),
1903				       64, CI_HDRC_PAGE_SIZE);
1904	if (ci->qh_pool == NULL)
1905		return -ENOMEM;
1906
1907	ci->td_pool = dma_pool_create("ci_hw_td", dev,
1908				       sizeof(struct ci_hw_td),
1909				       64, CI_HDRC_PAGE_SIZE);
1910	if (ci->td_pool == NULL) {
1911		retval = -ENOMEM;
1912		goto free_qh_pool;
1913	}
1914
1915	retval = init_eps(ci);
1916	if (retval)
1917		goto free_pools;
1918
1919	ci->gadget.ep0 = &ci->ep0in->ep;
1920
1921	retval = usb_add_gadget_udc(dev, &ci->gadget);
1922	if (retval)
1923		goto destroy_eps;
1924
1925	pm_runtime_no_callbacks(&ci->gadget.dev);
1926	pm_runtime_enable(&ci->gadget.dev);
1927
1928	return retval;
1929
1930destroy_eps:
1931	destroy_eps(ci);
1932free_pools:
1933	dma_pool_destroy(ci->td_pool);
1934free_qh_pool:
1935	dma_pool_destroy(ci->qh_pool);
1936	return retval;
1937}
1938
1939/**
1940 * ci_hdrc_gadget_destroy: parent remove must call this to remove UDC
1941 *
1942 * No interrupts active, the IRQ has been released
1943 */
1944void ci_hdrc_gadget_destroy(struct ci_hdrc *ci)
1945{
1946	if (!ci->roles[CI_ROLE_GADGET])
1947		return;
1948
1949	usb_del_gadget_udc(&ci->gadget);
1950
1951	destroy_eps(ci);
1952
1953	dma_pool_destroy(ci->td_pool);
1954	dma_pool_destroy(ci->qh_pool);
1955}
1956
1957static int udc_id_switch_for_device(struct ci_hdrc *ci)
1958{
1959	if (ci->is_otg)
1960		/* Clear and enable BSV irq */
1961		hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
1962					OTGSC_BSVIS | OTGSC_BSVIE);
1963
1964	return 0;
1965}
1966
1967static void udc_id_switch_for_host(struct ci_hdrc *ci)
1968{
1969	/*
1970	 * host doesn't care B_SESSION_VALID event
1971	 * so clear and disbale BSV irq
1972	 */
1973	if (ci->is_otg)
1974		hw_write_otgsc(ci, OTGSC_BSVIE | OTGSC_BSVIS, OTGSC_BSVIS);
1975}
1976
1977/**
1978 * ci_hdrc_gadget_init - initialize device related bits
1979 * ci: the controller
1980 *
1981 * This function initializes the gadget, if the device is "device capable".
1982 */
1983int ci_hdrc_gadget_init(struct ci_hdrc *ci)
1984{
1985	struct ci_role_driver *rdrv;
1986
1987	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
1988		return -ENXIO;
1989
1990	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
1991	if (!rdrv)
1992		return -ENOMEM;
1993
1994	rdrv->start	= udc_id_switch_for_device;
1995	rdrv->stop	= udc_id_switch_for_host;
1996	rdrv->irq	= udc_irq;
1997	rdrv->name	= "gadget";
1998	ci->roles[CI_ROLE_GADGET] = rdrv;
1999
2000	return udc_start(ci);
2001}