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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 1999 - 2010 Intel Corporation.
   4 * Copyright (C) 2010 LAPIS SEMICONDUCTOR CO., LTD.
   5 */
   6
   7#include <linux/interrupt.h>
   8#include <linux/delay.h>
   9#include <linux/io.h>
  10#include <linux/module.h>
  11#include <linux/sched.h>
  12#include <linux/pci.h>
  13#include <linux/kernel.h>
  14#include <linux/types.h>
  15#include <linux/errno.h>
  16#include <linux/netdevice.h>
  17#include <linux/skbuff.h>
  18#include <linux/can.h>
  19#include <linux/can/dev.h>
  20#include <linux/can/error.h>
  21
  22#define PCH_CTRL_INIT		BIT(0) /* The INIT bit of CANCONT register. */
  23#define PCH_CTRL_IE		BIT(1) /* The IE bit of CAN control register */
  24#define PCH_CTRL_IE_SIE_EIE	(BIT(3) | BIT(2) | BIT(1))
  25#define PCH_CTRL_CCE		BIT(6)
  26#define PCH_CTRL_OPT		BIT(7) /* The OPT bit of CANCONT register. */
  27#define PCH_OPT_SILENT		BIT(3) /* The Silent bit of CANOPT reg. */
  28#define PCH_OPT_LBACK		BIT(4) /* The LoopBack bit of CANOPT reg. */
  29
  30#define PCH_CMASK_RX_TX_SET	0x00f3
  31#define PCH_CMASK_RX_TX_GET	0x0073
  32#define PCH_CMASK_ALL		0xff
  33#define PCH_CMASK_NEWDAT	BIT(2)
  34#define PCH_CMASK_CLRINTPND	BIT(3)
  35#define PCH_CMASK_CTRL		BIT(4)
  36#define PCH_CMASK_ARB		BIT(5)
  37#define PCH_CMASK_MASK		BIT(6)
  38#define PCH_CMASK_RDWR		BIT(7)
  39#define PCH_IF_MCONT_NEWDAT	BIT(15)
  40#define PCH_IF_MCONT_MSGLOST	BIT(14)
  41#define PCH_IF_MCONT_INTPND	BIT(13)
  42#define PCH_IF_MCONT_UMASK	BIT(12)
  43#define PCH_IF_MCONT_TXIE	BIT(11)
  44#define PCH_IF_MCONT_RXIE	BIT(10)
  45#define PCH_IF_MCONT_RMTEN	BIT(9)
  46#define PCH_IF_MCONT_TXRQXT	BIT(8)
  47#define PCH_IF_MCONT_EOB	BIT(7)
  48#define PCH_IF_MCONT_DLC	(BIT(0) | BIT(1) | BIT(2) | BIT(3))
  49#define PCH_MASK2_MDIR_MXTD	(BIT(14) | BIT(15))
  50#define PCH_ID2_DIR		BIT(13)
  51#define PCH_ID2_XTD		BIT(14)
  52#define PCH_ID_MSGVAL		BIT(15)
  53#define PCH_IF_CREQ_BUSY	BIT(15)
  54
  55#define PCH_STATUS_INT		0x8000
  56#define PCH_RP			0x00008000
  57#define PCH_REC			0x00007f00
  58#define PCH_TEC			0x000000ff
  59
  60#define PCH_TX_OK		BIT(3)
  61#define PCH_RX_OK		BIT(4)
  62#define PCH_EPASSIV		BIT(5)
  63#define PCH_EWARN		BIT(6)
  64#define PCH_BUS_OFF		BIT(7)
  65
  66/* bit position of certain controller bits. */
  67#define PCH_BIT_BRP_SHIFT	0
  68#define PCH_BIT_SJW_SHIFT	6
  69#define PCH_BIT_TSEG1_SHIFT	8
  70#define PCH_BIT_TSEG2_SHIFT	12
  71#define PCH_BIT_BRPE_BRPE_SHIFT	6
  72
  73#define PCH_MSK_BITT_BRP	0x3f
  74#define PCH_MSK_BRPE_BRPE	0x3c0
  75#define PCH_MSK_CTRL_IE_SIE_EIE	0x07
  76#define PCH_COUNTER_LIMIT	10
  77
  78#define PCH_CAN_CLK		50000000	/* 50MHz */
  79
  80/*
  81 * Define the number of message object.
  82 * PCH CAN communications are done via Message RAM.
  83 * The Message RAM consists of 32 message objects.
  84 */
  85#define PCH_RX_OBJ_NUM		26
  86#define PCH_TX_OBJ_NUM		6
  87#define PCH_RX_OBJ_START	1
  88#define PCH_RX_OBJ_END		PCH_RX_OBJ_NUM
  89#define PCH_TX_OBJ_START	(PCH_RX_OBJ_END + 1)
  90#define PCH_TX_OBJ_END		(PCH_RX_OBJ_NUM + PCH_TX_OBJ_NUM)
  91
  92#define PCH_FIFO_THRESH		16
  93
  94/* TxRqst2 show status of MsgObjNo.17~32 */
  95#define PCH_TREQ2_TX_MASK	(((1 << PCH_TX_OBJ_NUM) - 1) <<\
  96							(PCH_RX_OBJ_END - 16))
  97
  98enum pch_ifreg {
  99	PCH_RX_IFREG,
 100	PCH_TX_IFREG,
 101};
 102
 103enum pch_can_err {
 104	PCH_STUF_ERR = 1,
 105	PCH_FORM_ERR,
 106	PCH_ACK_ERR,
 107	PCH_BIT1_ERR,
 108	PCH_BIT0_ERR,
 109	PCH_CRC_ERR,
 110	PCH_LEC_ALL,
 111};
 112
 113enum pch_can_mode {
 114	PCH_CAN_ENABLE,
 115	PCH_CAN_DISABLE,
 116	PCH_CAN_ALL,
 117	PCH_CAN_NONE,
 118	PCH_CAN_STOP,
 119	PCH_CAN_RUN,
 120};
 121
 122struct pch_can_if_regs {
 123	u32 creq;
 124	u32 cmask;
 125	u32 mask1;
 126	u32 mask2;
 127	u32 id1;
 128	u32 id2;
 129	u32 mcont;
 130	u32 data[4];
 131	u32 rsv[13];
 132};
 133
 134struct pch_can_regs {
 135	u32 cont;
 136	u32 stat;
 137	u32 errc;
 138	u32 bitt;
 139	u32 intr;
 140	u32 opt;
 141	u32 brpe;
 142	u32 reserve;
 143	struct pch_can_if_regs ifregs[2]; /* [0]=if1  [1]=if2 */
 144	u32 reserve1[8];
 145	u32 treq1;
 146	u32 treq2;
 147	u32 reserve2[6];
 148	u32 data1;
 149	u32 data2;
 150	u32 reserve3[6];
 151	u32 canipend1;
 152	u32 canipend2;
 153	u32 reserve4[6];
 154	u32 canmval1;
 155	u32 canmval2;
 156	u32 reserve5[37];
 157	u32 srst;
 158};
 159
 160struct pch_can_priv {
 161	struct can_priv can;
 162	struct pci_dev *dev;
 163	u32 tx_enable[PCH_TX_OBJ_END];
 164	u32 rx_enable[PCH_TX_OBJ_END];
 165	u32 rx_link[PCH_TX_OBJ_END];
 166	u32 int_enables;
 167	struct net_device *ndev;
 168	struct pch_can_regs __iomem *regs;
 169	struct napi_struct napi;
 170	int tx_obj;	/* Point next Tx Obj index */
 171	int use_msi;
 172};
 173
 174static const struct can_bittiming_const pch_can_bittiming_const = {
 175	.name = KBUILD_MODNAME,
 176	.tseg1_min = 2,
 177	.tseg1_max = 16,
 178	.tseg2_min = 1,
 179	.tseg2_max = 8,
 180	.sjw_max = 4,
 181	.brp_min = 1,
 182	.brp_max = 1024, /* 6bit + extended 4bit */
 183	.brp_inc = 1,
 184};
 185
 186static const struct pci_device_id pch_pci_tbl[] = {
 187	{PCI_VENDOR_ID_INTEL, 0x8818, PCI_ANY_ID, PCI_ANY_ID,},
 188	{0,}
 189};
 190MODULE_DEVICE_TABLE(pci, pch_pci_tbl);
 191
 192static inline void pch_can_bit_set(void __iomem *addr, u32 mask)
 193{
 194	iowrite32(ioread32(addr) | mask, addr);
 195}
 196
 197static inline void pch_can_bit_clear(void __iomem *addr, u32 mask)
 198{
 199	iowrite32(ioread32(addr) & ~mask, addr);
 200}
 201
 202static void pch_can_set_run_mode(struct pch_can_priv *priv,
 203				 enum pch_can_mode mode)
 204{
 205	switch (mode) {
 206	case PCH_CAN_RUN:
 207		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_INIT);
 208		break;
 209
 210	case PCH_CAN_STOP:
 211		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_INIT);
 212		break;
 213
 214	default:
 215		netdev_err(priv->ndev, "%s -> Invalid Mode.\n", __func__);
 216		break;
 217	}
 218}
 219
 220static void pch_can_set_optmode(struct pch_can_priv *priv)
 221{
 222	u32 reg_val = ioread32(&priv->regs->opt);
 223
 224	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 225		reg_val |= PCH_OPT_SILENT;
 226
 227	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
 228		reg_val |= PCH_OPT_LBACK;
 229
 230	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_OPT);
 231	iowrite32(reg_val, &priv->regs->opt);
 232}
 233
 234static void pch_can_rw_msg_obj(void __iomem *creq_addr, u32 num)
 235{
 236	int counter = PCH_COUNTER_LIMIT;
 237	u32 ifx_creq;
 238
 239	iowrite32(num, creq_addr);
 240	while (counter) {
 241		ifx_creq = ioread32(creq_addr) & PCH_IF_CREQ_BUSY;
 242		if (!ifx_creq)
 243			break;
 244		counter--;
 245		udelay(1);
 246	}
 247	if (!counter)
 248		pr_err("%s:IF1 BUSY Flag is set forever.\n", __func__);
 249}
 250
 251static void pch_can_set_int_enables(struct pch_can_priv *priv,
 252				    enum pch_can_mode interrupt_no)
 253{
 254	switch (interrupt_no) {
 255	case PCH_CAN_DISABLE:
 256		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE);
 257		break;
 258
 259	case PCH_CAN_ALL:
 260		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 261		break;
 262
 263	case PCH_CAN_NONE:
 264		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 265		break;
 266
 267	default:
 268		netdev_err(priv->ndev, "Invalid interrupt number.\n");
 269		break;
 270	}
 271}
 272
 273static void pch_can_set_rxtx(struct pch_can_priv *priv, u32 buff_num,
 274			     int set, enum pch_ifreg dir)
 275{
 276	u32 ie;
 277
 278	if (dir)
 279		ie = PCH_IF_MCONT_TXIE;
 280	else
 281		ie = PCH_IF_MCONT_RXIE;
 282
 283	/* Reading the Msg buffer from Message RAM to IF1/2 registers. */
 284	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
 285	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 286
 287	/* Setting the IF1/2MASK1 register to access MsgVal and RxIE bits */
 288	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_ARB | PCH_CMASK_CTRL,
 289		  &priv->regs->ifregs[dir].cmask);
 290
 291	if (set) {
 292		/* Setting the MsgVal and RxIE/TxIE bits */
 293		pch_can_bit_set(&priv->regs->ifregs[dir].mcont, ie);
 294		pch_can_bit_set(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
 295	} else {
 296		/* Clearing the MsgVal and RxIE/TxIE bits */
 297		pch_can_bit_clear(&priv->regs->ifregs[dir].mcont, ie);
 298		pch_can_bit_clear(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
 299	}
 300
 301	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 302}
 303
 304static void pch_can_set_rx_all(struct pch_can_priv *priv, int set)
 305{
 306	int i;
 307
 308	/* Traversing to obtain the object configured as receivers. */
 309	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++)
 310		pch_can_set_rxtx(priv, i, set, PCH_RX_IFREG);
 311}
 312
 313static void pch_can_set_tx_all(struct pch_can_priv *priv, int set)
 314{
 315	int i;
 316
 317	/* Traversing to obtain the object configured as transmit object. */
 318	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
 319		pch_can_set_rxtx(priv, i, set, PCH_TX_IFREG);
 320}
 321
 322static u32 pch_can_int_pending(struct pch_can_priv *priv)
 323{
 324	return ioread32(&priv->regs->intr) & 0xffff;
 325}
 326
 327static void pch_can_clear_if_buffers(struct pch_can_priv *priv)
 328{
 329	int i; /* Msg Obj ID (1~32) */
 330
 331	for (i = PCH_RX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
 332		iowrite32(PCH_CMASK_RX_TX_SET, &priv->regs->ifregs[0].cmask);
 333		iowrite32(0xffff, &priv->regs->ifregs[0].mask1);
 334		iowrite32(0xffff, &priv->regs->ifregs[0].mask2);
 335		iowrite32(0x0, &priv->regs->ifregs[0].id1);
 336		iowrite32(0x0, &priv->regs->ifregs[0].id2);
 337		iowrite32(0x0, &priv->regs->ifregs[0].mcont);
 338		iowrite32(0x0, &priv->regs->ifregs[0].data[0]);
 339		iowrite32(0x0, &priv->regs->ifregs[0].data[1]);
 340		iowrite32(0x0, &priv->regs->ifregs[0].data[2]);
 341		iowrite32(0x0, &priv->regs->ifregs[0].data[3]);
 342		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK |
 343			  PCH_CMASK_ARB | PCH_CMASK_CTRL,
 344			  &priv->regs->ifregs[0].cmask);
 345		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 346	}
 347}
 348
 349static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
 350{
 351	int i;
 352
 353	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
 354		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
 355		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 356
 357		iowrite32(0x0, &priv->regs->ifregs[0].id1);
 358		iowrite32(0x0, &priv->regs->ifregs[0].id2);
 359
 360		pch_can_bit_set(&priv->regs->ifregs[0].mcont,
 361				PCH_IF_MCONT_UMASK);
 362
 363		/* In case FIFO mode, Last EoB of Rx Obj must be 1 */
 364		if (i == PCH_RX_OBJ_END)
 365			pch_can_bit_set(&priv->regs->ifregs[0].mcont,
 366					PCH_IF_MCONT_EOB);
 367		else
 368			pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 369					  PCH_IF_MCONT_EOB);
 370
 371		iowrite32(0, &priv->regs->ifregs[0].mask1);
 372		pch_can_bit_clear(&priv->regs->ifregs[0].mask2,
 373				  0x1fff | PCH_MASK2_MDIR_MXTD);
 374
 375		/* Setting CMASK for writing */
 376		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
 377			  PCH_CMASK_CTRL, &priv->regs->ifregs[0].cmask);
 378
 379		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 380	}
 381
 382	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
 383		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[1].cmask);
 384		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
 385
 386		/* Resetting DIR bit for reception */
 387		iowrite32(0x0, &priv->regs->ifregs[1].id1);
 388		iowrite32(PCH_ID2_DIR, &priv->regs->ifregs[1].id2);
 389
 390		/* Setting EOB bit for transmitter */
 391		iowrite32(PCH_IF_MCONT_EOB | PCH_IF_MCONT_UMASK,
 392			  &priv->regs->ifregs[1].mcont);
 393
 394		iowrite32(0, &priv->regs->ifregs[1].mask1);
 395		pch_can_bit_clear(&priv->regs->ifregs[1].mask2, 0x1fff);
 396
 397		/* Setting CMASK for writing */
 398		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
 399			  PCH_CMASK_CTRL, &priv->regs->ifregs[1].cmask);
 400
 401		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
 402	}
 403}
 404
 405static void pch_can_init(struct pch_can_priv *priv)
 406{
 407	/* Stopping the Can device. */
 408	pch_can_set_run_mode(priv, PCH_CAN_STOP);
 409
 410	/* Clearing all the message object buffers. */
 411	pch_can_clear_if_buffers(priv);
 412
 413	/* Configuring the respective message object as either rx/tx object. */
 414	pch_can_config_rx_tx_buffers(priv);
 415
 416	/* Enabling the interrupts. */
 417	pch_can_set_int_enables(priv, PCH_CAN_ALL);
 418}
 419
 420static void pch_can_release(struct pch_can_priv *priv)
 421{
 422	/* Stooping the CAN device. */
 423	pch_can_set_run_mode(priv, PCH_CAN_STOP);
 424
 425	/* Disabling the interrupts. */
 426	pch_can_set_int_enables(priv, PCH_CAN_NONE);
 427
 428	/* Disabling all the receive object. */
 429	pch_can_set_rx_all(priv, 0);
 430
 431	/* Disabling all the transmit object. */
 432	pch_can_set_tx_all(priv, 0);
 433}
 434
 435/* This function clears interrupt(s) from the CAN device. */
 436static void pch_can_int_clr(struct pch_can_priv *priv, u32 mask)
 437{
 438	/* Clear interrupt for transmit object */
 439	if ((mask >= PCH_RX_OBJ_START) && (mask <= PCH_RX_OBJ_END)) {
 440		/* Setting CMASK for clearing the reception interrupts. */
 441		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
 442			  &priv->regs->ifregs[0].cmask);
 443
 444		/* Clearing the Dir bit. */
 445		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
 446
 447		/* Clearing NewDat & IntPnd */
 448		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 449				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND);
 450
 451		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, mask);
 452	} else if ((mask >= PCH_TX_OBJ_START) && (mask <= PCH_TX_OBJ_END)) {
 453		/*
 454		 * Setting CMASK for clearing interrupts for frame transmission.
 455		 */
 456		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
 457			  &priv->regs->ifregs[1].cmask);
 458
 459		/* Resetting the ID registers. */
 460		pch_can_bit_set(&priv->regs->ifregs[1].id2,
 461			       PCH_ID2_DIR | (0x7ff << 2));
 462		iowrite32(0x0, &priv->regs->ifregs[1].id1);
 463
 464		/* Clearing NewDat, TxRqst & IntPnd */
 465		pch_can_bit_clear(&priv->regs->ifregs[1].mcont,
 466				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND |
 467				  PCH_IF_MCONT_TXRQXT);
 468		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, mask);
 469	}
 470}
 471
 472static void pch_can_reset(struct pch_can_priv *priv)
 473{
 474	/* write to sw reset register */
 475	iowrite32(1, &priv->regs->srst);
 476	iowrite32(0, &priv->regs->srst);
 477}
 478
 479static void pch_can_error(struct net_device *ndev, u32 status)
 480{
 481	struct sk_buff *skb;
 482	struct pch_can_priv *priv = netdev_priv(ndev);
 483	struct can_frame *cf;
 484	u32 errc, lec;
 485	struct net_device_stats *stats = &(priv->ndev->stats);
 486	enum can_state state = priv->can.state;
 487
 488	skb = alloc_can_err_skb(ndev, &cf);
 489	if (!skb)
 490		return;
 491
 492	if (status & PCH_BUS_OFF) {
 493		pch_can_set_tx_all(priv, 0);
 494		pch_can_set_rx_all(priv, 0);
 495		state = CAN_STATE_BUS_OFF;
 496		cf->can_id |= CAN_ERR_BUSOFF;
 497		priv->can.can_stats.bus_off++;
 498		can_bus_off(ndev);
 499	}
 500
 501	errc = ioread32(&priv->regs->errc);
 502	/* Warning interrupt. */
 503	if (status & PCH_EWARN) {
 504		state = CAN_STATE_ERROR_WARNING;
 505		priv->can.can_stats.error_warning++;
 506		cf->can_id |= CAN_ERR_CRTL;
 507		if (((errc & PCH_REC) >> 8) > 96)
 508			cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
 509		if ((errc & PCH_TEC) > 96)
 510			cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
 511		netdev_dbg(ndev,
 512			"%s -> Error Counter is more than 96.\n", __func__);
 513	}
 514	/* Error passive interrupt. */
 515	if (status & PCH_EPASSIV) {
 516		priv->can.can_stats.error_passive++;
 517		state = CAN_STATE_ERROR_PASSIVE;
 518		cf->can_id |= CAN_ERR_CRTL;
 519		if (errc & PCH_RP)
 520			cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
 521		if ((errc & PCH_TEC) > 127)
 522			cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
 523		netdev_dbg(ndev,
 524			"%s -> CAN controller is ERROR PASSIVE .\n", __func__);
 525	}
 526
 527	lec = status & PCH_LEC_ALL;
 528	switch (lec) {
 529	case PCH_STUF_ERR:
 530		cf->data[2] |= CAN_ERR_PROT_STUFF;
 531		priv->can.can_stats.bus_error++;
 532		stats->rx_errors++;
 533		break;
 534	case PCH_FORM_ERR:
 535		cf->data[2] |= CAN_ERR_PROT_FORM;
 536		priv->can.can_stats.bus_error++;
 537		stats->rx_errors++;
 538		break;
 539	case PCH_ACK_ERR:
 540		cf->can_id |= CAN_ERR_ACK;
 541		priv->can.can_stats.bus_error++;
 542		stats->rx_errors++;
 543		break;
 544	case PCH_BIT1_ERR:
 545	case PCH_BIT0_ERR:
 546		cf->data[2] |= CAN_ERR_PROT_BIT;
 547		priv->can.can_stats.bus_error++;
 548		stats->rx_errors++;
 549		break;
 550	case PCH_CRC_ERR:
 551		cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
 552		priv->can.can_stats.bus_error++;
 553		stats->rx_errors++;
 554		break;
 555	case PCH_LEC_ALL: /* Written by CPU. No error status */
 556		break;
 557	}
 558
 559	cf->data[6] = errc & PCH_TEC;
 560	cf->data[7] = (errc & PCH_REC) >> 8;
 561
 562	priv->can.state = state;
 563	netif_receive_skb(skb);
 564
 565	stats->rx_packets++;
 566	stats->rx_bytes += cf->len;
 567}
 568
 569static irqreturn_t pch_can_interrupt(int irq, void *dev_id)
 570{
 571	struct net_device *ndev = (struct net_device *)dev_id;
 572	struct pch_can_priv *priv = netdev_priv(ndev);
 573
 574	if (!pch_can_int_pending(priv))
 575		return IRQ_NONE;
 576
 577	pch_can_set_int_enables(priv, PCH_CAN_NONE);
 578	napi_schedule(&priv->napi);
 579	return IRQ_HANDLED;
 580}
 581
 582static void pch_fifo_thresh(struct pch_can_priv *priv, int obj_id)
 583{
 584	if (obj_id < PCH_FIFO_THRESH) {
 585		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL |
 586			  PCH_CMASK_ARB, &priv->regs->ifregs[0].cmask);
 587
 588		/* Clearing the Dir bit. */
 589		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
 590
 591		/* Clearing NewDat & IntPnd */
 592		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 593				  PCH_IF_MCONT_INTPND);
 594		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
 595	} else if (obj_id > PCH_FIFO_THRESH) {
 596		pch_can_int_clr(priv, obj_id);
 597	} else if (obj_id == PCH_FIFO_THRESH) {
 598		int cnt;
 599		for (cnt = 0; cnt < PCH_FIFO_THRESH; cnt++)
 600			pch_can_int_clr(priv, cnt + 1);
 601	}
 602}
 603
 604static void pch_can_rx_msg_lost(struct net_device *ndev, int obj_id)
 605{
 606	struct pch_can_priv *priv = netdev_priv(ndev);
 607	struct net_device_stats *stats = &(priv->ndev->stats);
 608	struct sk_buff *skb;
 609	struct can_frame *cf;
 610
 611	netdev_dbg(priv->ndev, "Msg Obj is overwritten.\n");
 612	pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 613			  PCH_IF_MCONT_MSGLOST);
 614	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
 615		  &priv->regs->ifregs[0].cmask);
 616	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
 617
 618	skb = alloc_can_err_skb(ndev, &cf);
 619	if (!skb)
 620		return;
 621
 622	cf->can_id |= CAN_ERR_CRTL;
 623	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 624	stats->rx_over_errors++;
 625	stats->rx_errors++;
 626
 627	netif_receive_skb(skb);
 628}
 629
 630static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota)
 631{
 632	u32 reg;
 633	canid_t id;
 634	int rcv_pkts = 0;
 635	struct sk_buff *skb;
 636	struct can_frame *cf;
 637	struct pch_can_priv *priv = netdev_priv(ndev);
 638	struct net_device_stats *stats = &(priv->ndev->stats);
 639	int i;
 640	u32 id2;
 641	u16 data_reg;
 642
 643	do {
 644		/* Reading the message object from the Message RAM */
 645		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
 646		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_num);
 647
 648		/* Reading the MCONT register. */
 649		reg = ioread32(&priv->regs->ifregs[0].mcont);
 650
 651		if (reg & PCH_IF_MCONT_EOB)
 652			break;
 653
 654		/* If MsgLost bit set. */
 655		if (reg & PCH_IF_MCONT_MSGLOST) {
 656			pch_can_rx_msg_lost(ndev, obj_num);
 657			rcv_pkts++;
 658			quota--;
 659			obj_num++;
 660			continue;
 661		} else if (!(reg & PCH_IF_MCONT_NEWDAT)) {
 662			obj_num++;
 663			continue;
 664		}
 665
 666		skb = alloc_can_skb(priv->ndev, &cf);
 667		if (!skb) {
 668			netdev_err(ndev, "alloc_can_skb Failed\n");
 669			return rcv_pkts;
 670		}
 671
 672		/* Get Received data */
 673		id2 = ioread32(&priv->regs->ifregs[0].id2);
 674		if (id2 & PCH_ID2_XTD) {
 675			id = (ioread32(&priv->regs->ifregs[0].id1) & 0xffff);
 676			id |= (((id2) & 0x1fff) << 16);
 677			cf->can_id = id | CAN_EFF_FLAG;
 678		} else {
 679			id = (id2 >> 2) & CAN_SFF_MASK;
 680			cf->can_id = id;
 681		}
 682
 683		if (id2 & PCH_ID2_DIR)
 684			cf->can_id |= CAN_RTR_FLAG;
 685
 686		cf->len = can_cc_dlc2len((ioread32(&priv->regs->
 687						    ifregs[0].mcont)) & 0xF);
 688
 689		for (i = 0; i < cf->len; i += 2) {
 690			data_reg = ioread16(&priv->regs->ifregs[0].data[i / 2]);
 691			cf->data[i] = data_reg;
 692			cf->data[i + 1] = data_reg >> 8;
 693		}
 694
 695		netif_receive_skb(skb);
 696		rcv_pkts++;
 697		stats->rx_packets++;
 698		quota--;
 699		stats->rx_bytes += cf->len;
 700
 701		pch_fifo_thresh(priv, obj_num);
 702		obj_num++;
 703	} while (quota > 0);
 704
 705	return rcv_pkts;
 706}
 707
 708static void pch_can_tx_complete(struct net_device *ndev, u32 int_stat)
 709{
 710	struct pch_can_priv *priv = netdev_priv(ndev);
 711	struct net_device_stats *stats = &(priv->ndev->stats);
 712	u32 dlc;
 713
 714	can_get_echo_skb(ndev, int_stat - PCH_RX_OBJ_END - 1, NULL);
 715	iowrite32(PCH_CMASK_RX_TX_GET | PCH_CMASK_CLRINTPND,
 716		  &priv->regs->ifregs[1].cmask);
 717	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, int_stat);
 718	dlc = can_cc_dlc2len(ioread32(&priv->regs->ifregs[1].mcont) &
 719			  PCH_IF_MCONT_DLC);
 720	stats->tx_bytes += dlc;
 721	stats->tx_packets++;
 722	if (int_stat == PCH_TX_OBJ_END)
 723		netif_wake_queue(ndev);
 724}
 725
 726static int pch_can_poll(struct napi_struct *napi, int quota)
 727{
 728	struct net_device *ndev = napi->dev;
 729	struct pch_can_priv *priv = netdev_priv(ndev);
 730	u32 int_stat;
 731	u32 reg_stat;
 732	int quota_save = quota;
 733
 734	int_stat = pch_can_int_pending(priv);
 735	if (!int_stat)
 736		goto end;
 737
 738	if (int_stat == PCH_STATUS_INT) {
 739		reg_stat = ioread32(&priv->regs->stat);
 740
 741		if ((reg_stat & (PCH_BUS_OFF | PCH_LEC_ALL)) &&
 742		   ((reg_stat & PCH_LEC_ALL) != PCH_LEC_ALL)) {
 743			pch_can_error(ndev, reg_stat);
 744			quota--;
 745		}
 746
 747		if (reg_stat & (PCH_TX_OK | PCH_RX_OK))
 748			pch_can_bit_clear(&priv->regs->stat,
 749					  reg_stat & (PCH_TX_OK | PCH_RX_OK));
 750
 751		int_stat = pch_can_int_pending(priv);
 752	}
 753
 754	if (quota == 0)
 755		goto end;
 756
 757	if ((int_stat >= PCH_RX_OBJ_START) && (int_stat <= PCH_RX_OBJ_END)) {
 758		quota -= pch_can_rx_normal(ndev, int_stat, quota);
 759	} else if ((int_stat >= PCH_TX_OBJ_START) &&
 760		   (int_stat <= PCH_TX_OBJ_END)) {
 761		/* Handle transmission interrupt */
 762		pch_can_tx_complete(ndev, int_stat);
 763	}
 764
 765end:
 766	napi_complete(napi);
 767	pch_can_set_int_enables(priv, PCH_CAN_ALL);
 768
 769	return quota_save - quota;
 770}
 771
 772static int pch_set_bittiming(struct net_device *ndev)
 773{
 774	struct pch_can_priv *priv = netdev_priv(ndev);
 775	const struct can_bittiming *bt = &priv->can.bittiming;
 776	u32 canbit;
 777	u32 bepe;
 778
 779	/* Setting the CCE bit for accessing the Can Timing register. */
 780	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_CCE);
 781
 782	canbit = (bt->brp - 1) & PCH_MSK_BITT_BRP;
 783	canbit |= (bt->sjw - 1) << PCH_BIT_SJW_SHIFT;
 784	canbit |= (bt->phase_seg1 + bt->prop_seg - 1) << PCH_BIT_TSEG1_SHIFT;
 785	canbit |= (bt->phase_seg2 - 1) << PCH_BIT_TSEG2_SHIFT;
 786	bepe = ((bt->brp - 1) & PCH_MSK_BRPE_BRPE) >> PCH_BIT_BRPE_BRPE_SHIFT;
 787	iowrite32(canbit, &priv->regs->bitt);
 788	iowrite32(bepe, &priv->regs->brpe);
 789	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_CCE);
 790
 791	return 0;
 792}
 793
 794static void pch_can_start(struct net_device *ndev)
 795{
 796	struct pch_can_priv *priv = netdev_priv(ndev);
 797
 798	if (priv->can.state != CAN_STATE_STOPPED)
 799		pch_can_reset(priv);
 800
 801	pch_set_bittiming(ndev);
 802	pch_can_set_optmode(priv);
 803
 804	pch_can_set_tx_all(priv, 1);
 805	pch_can_set_rx_all(priv, 1);
 806
 807	/* Setting the CAN to run mode. */
 808	pch_can_set_run_mode(priv, PCH_CAN_RUN);
 809
 810	priv->can.state = CAN_STATE_ERROR_ACTIVE;
 811
 812	return;
 813}
 814
 815static int pch_can_do_set_mode(struct net_device *ndev, enum can_mode mode)
 816{
 817	int ret = 0;
 818
 819	switch (mode) {
 820	case CAN_MODE_START:
 821		pch_can_start(ndev);
 822		netif_wake_queue(ndev);
 823		break;
 824	default:
 825		ret = -EOPNOTSUPP;
 826		break;
 827	}
 828
 829	return ret;
 830}
 831
 832static int pch_can_open(struct net_device *ndev)
 833{
 834	struct pch_can_priv *priv = netdev_priv(ndev);
 835	int retval;
 836
 837	/* Registering the interrupt. */
 838	retval = request_irq(priv->dev->irq, pch_can_interrupt, IRQF_SHARED,
 839			     ndev->name, ndev);
 840	if (retval) {
 841		netdev_err(ndev, "request_irq failed.\n");
 842		goto req_irq_err;
 843	}
 844
 845	/* Open common can device */
 846	retval = open_candev(ndev);
 847	if (retval) {
 848		netdev_err(ndev, "open_candev() failed %d\n", retval);
 849		goto err_open_candev;
 850	}
 851
 852	pch_can_init(priv);
 853	pch_can_start(ndev);
 854	napi_enable(&priv->napi);
 855	netif_start_queue(ndev);
 856
 857	return 0;
 858
 859err_open_candev:
 860	free_irq(priv->dev->irq, ndev);
 861req_irq_err:
 862	pch_can_release(priv);
 863
 864	return retval;
 865}
 866
 867static int pch_close(struct net_device *ndev)
 868{
 869	struct pch_can_priv *priv = netdev_priv(ndev);
 870
 871	netif_stop_queue(ndev);
 872	napi_disable(&priv->napi);
 873	pch_can_release(priv);
 874	free_irq(priv->dev->irq, ndev);
 875	close_candev(ndev);
 876	priv->can.state = CAN_STATE_STOPPED;
 877	return 0;
 878}
 879
 880static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
 881{
 882	struct pch_can_priv *priv = netdev_priv(ndev);
 883	struct can_frame *cf = (struct can_frame *)skb->data;
 884	int tx_obj_no;
 885	int i;
 886	u32 id2;
 887
 888	if (can_dropped_invalid_skb(ndev, skb))
 889		return NETDEV_TX_OK;
 890
 891	tx_obj_no = priv->tx_obj;
 892	if (priv->tx_obj == PCH_TX_OBJ_END) {
 893		if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK)
 894			netif_stop_queue(ndev);
 895
 896		priv->tx_obj = PCH_TX_OBJ_START;
 897	} else {
 898		priv->tx_obj++;
 899	}
 900
 901	/* Setting the CMASK register. */
 902	pch_can_bit_set(&priv->regs->ifregs[1].cmask, PCH_CMASK_ALL);
 903
 904	/* If ID extended is set. */
 905	if (cf->can_id & CAN_EFF_FLAG) {
 906		iowrite32(cf->can_id & 0xffff, &priv->regs->ifregs[1].id1);
 907		id2 = ((cf->can_id >> 16) & 0x1fff) | PCH_ID2_XTD;
 908	} else {
 909		iowrite32(0, &priv->regs->ifregs[1].id1);
 910		id2 = (cf->can_id & CAN_SFF_MASK) << 2;
 911	}
 912
 913	id2 |= PCH_ID_MSGVAL;
 914
 915	/* If remote frame has to be transmitted.. */
 916	if (!(cf->can_id & CAN_RTR_FLAG))
 917		id2 |= PCH_ID2_DIR;
 918
 919	iowrite32(id2, &priv->regs->ifregs[1].id2);
 920
 921	/* Copy data to register */
 922	for (i = 0; i < cf->len; i += 2) {
 923		iowrite16(cf->data[i] | (cf->data[i + 1] << 8),
 924			  &priv->regs->ifregs[1].data[i / 2]);
 925	}
 926
 927	can_put_echo_skb(skb, ndev, tx_obj_no - PCH_RX_OBJ_END - 1, 0);
 928
 929	/* Set the size of the data. Update if2_mcont */
 930	iowrite32(cf->len | PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_TXRQXT |
 931		  PCH_IF_MCONT_TXIE, &priv->regs->ifregs[1].mcont);
 932
 933	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no);
 934
 935	return NETDEV_TX_OK;
 936}
 937
 938static const struct net_device_ops pch_can_netdev_ops = {
 939	.ndo_open		= pch_can_open,
 940	.ndo_stop		= pch_close,
 941	.ndo_start_xmit		= pch_xmit,
 942	.ndo_change_mtu		= can_change_mtu,
 943};
 944
 945static void pch_can_remove(struct pci_dev *pdev)
 946{
 947	struct net_device *ndev = pci_get_drvdata(pdev);
 948	struct pch_can_priv *priv = netdev_priv(ndev);
 949
 950	unregister_candev(priv->ndev);
 951	if (priv->use_msi)
 952		pci_disable_msi(priv->dev);
 953	pci_release_regions(pdev);
 954	pci_disable_device(pdev);
 955	pch_can_reset(priv);
 956	pci_iounmap(pdev, priv->regs);
 957	free_candev(priv->ndev);
 958}
 959
 960static void __maybe_unused pch_can_set_int_custom(struct pch_can_priv *priv)
 961{
 962	/* Clearing the IE, SIE and EIE bits of Can control register. */
 963	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 964
 965	/* Appropriately setting them. */
 966	pch_can_bit_set(&priv->regs->cont,
 967			((priv->int_enables & PCH_MSK_CTRL_IE_SIE_EIE) << 1));
 968}
 969
 970/* This function retrieves interrupt enabled for the CAN device. */
 971static u32 __maybe_unused pch_can_get_int_enables(struct pch_can_priv *priv)
 972{
 973	/* Obtaining the status of IE, SIE and EIE interrupt bits. */
 974	return (ioread32(&priv->regs->cont) & PCH_CTRL_IE_SIE_EIE) >> 1;
 975}
 976
 977static u32 __maybe_unused pch_can_get_rxtx_ir(struct pch_can_priv *priv,
 978					      u32 buff_num, enum pch_ifreg dir)
 979{
 980	u32 ie, enable;
 981
 982	if (dir)
 983		ie = PCH_IF_MCONT_RXIE;
 984	else
 985		ie = PCH_IF_MCONT_TXIE;
 986
 987	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
 988	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 989
 990	if (((ioread32(&priv->regs->ifregs[dir].id2)) & PCH_ID_MSGVAL) &&
 991			((ioread32(&priv->regs->ifregs[dir].mcont)) & ie))
 992		enable = 1;
 993	else
 994		enable = 0;
 995
 996	return enable;
 997}
 998
 999static void __maybe_unused pch_can_set_rx_buffer_link(struct pch_can_priv *priv,
1000						      u32 buffer_num, int set)
1001{
1002	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1003	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1004	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
1005		  &priv->regs->ifregs[0].cmask);
1006	if (set)
1007		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
1008				  PCH_IF_MCONT_EOB);
1009	else
1010		pch_can_bit_set(&priv->regs->ifregs[0].mcont, PCH_IF_MCONT_EOB);
1011
1012	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1013}
1014
1015static u32 __maybe_unused pch_can_get_rx_buffer_link(struct pch_can_priv *priv,
1016						     u32 buffer_num)
1017{
1018	u32 link;
1019
1020	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1021	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1022
1023	if (ioread32(&priv->regs->ifregs[0].mcont) & PCH_IF_MCONT_EOB)
1024		link = 0;
1025	else
1026		link = 1;
1027	return link;
1028}
1029
1030static int __maybe_unused pch_can_get_buffer_status(struct pch_can_priv *priv)
1031{
1032	return (ioread32(&priv->regs->treq1) & 0xffff) |
1033	       (ioread32(&priv->regs->treq2) << 16);
1034}
1035
1036static int __maybe_unused pch_can_suspend(struct device *dev_d)
1037{
1038	int i;
1039	u32 buf_stat;	/* Variable for reading the transmit buffer status. */
1040	int counter = PCH_COUNTER_LIMIT;
1041
1042	struct net_device *dev = dev_get_drvdata(dev_d);
1043	struct pch_can_priv *priv = netdev_priv(dev);
1044
1045	/* Stop the CAN controller */
1046	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1047
1048	/* Indicate that we are aboutto/in suspend */
1049	priv->can.state = CAN_STATE_STOPPED;
1050
1051	/* Waiting for all transmission to complete. */
1052	while (counter) {
1053		buf_stat = pch_can_get_buffer_status(priv);
1054		if (!buf_stat)
1055			break;
1056		counter--;
1057		udelay(1);
1058	}
1059	if (!counter)
1060		dev_err(dev_d, "%s -> Transmission time out.\n", __func__);
1061
1062	/* Save interrupt configuration and then disable them */
1063	priv->int_enables = pch_can_get_int_enables(priv);
1064	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1065
1066	/* Save Tx buffer enable state */
1067	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1068		priv->tx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1069							     PCH_TX_IFREG);
1070
1071	/* Disable all Transmit buffers */
1072	pch_can_set_tx_all(priv, 0);
1073
1074	/* Save Rx buffer enable state */
1075	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1076		priv->rx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1077							     PCH_RX_IFREG);
1078		priv->rx_link[i - 1] = pch_can_get_rx_buffer_link(priv, i);
1079	}
1080
1081	/* Disable all Receive buffers */
1082	pch_can_set_rx_all(priv, 0);
1083
1084	return 0;
1085}
1086
1087static int __maybe_unused pch_can_resume(struct device *dev_d)
1088{
1089	int i;
1090	struct net_device *dev = dev_get_drvdata(dev_d);
1091	struct pch_can_priv *priv = netdev_priv(dev);
1092
1093	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1094
1095	/* Disabling all interrupts. */
1096	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1097
1098	/* Setting the CAN device in Stop Mode. */
1099	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1100
1101	/* Configuring the transmit and receive buffers. */
1102	pch_can_config_rx_tx_buffers(priv);
1103
1104	/* Restore the CAN state */
1105	pch_set_bittiming(dev);
1106
1107	/* Listen/Active */
1108	pch_can_set_optmode(priv);
1109
1110	/* Enabling the transmit buffer. */
1111	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1112		pch_can_set_rxtx(priv, i, priv->tx_enable[i - 1], PCH_TX_IFREG);
1113
1114	/* Configuring the receive buffer and enabling them. */
1115	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1116		/* Restore buffer link */
1117		pch_can_set_rx_buffer_link(priv, i, priv->rx_link[i - 1]);
1118
1119		/* Restore buffer enables */
1120		pch_can_set_rxtx(priv, i, priv->rx_enable[i - 1], PCH_RX_IFREG);
1121	}
1122
1123	/* Enable CAN Interrupts */
1124	pch_can_set_int_custom(priv);
1125
1126	/* Restore Run Mode */
1127	pch_can_set_run_mode(priv, PCH_CAN_RUN);
1128
1129	return 0;
1130}
1131
1132static int pch_can_get_berr_counter(const struct net_device *dev,
1133				    struct can_berr_counter *bec)
1134{
1135	struct pch_can_priv *priv = netdev_priv(dev);
1136	u32 errc = ioread32(&priv->regs->errc);
1137
1138	bec->txerr = errc & PCH_TEC;
1139	bec->rxerr = (errc & PCH_REC) >> 8;
1140
1141	return 0;
1142}
1143
1144static int pch_can_probe(struct pci_dev *pdev,
1145				   const struct pci_device_id *id)
1146{
1147	struct net_device *ndev;
1148	struct pch_can_priv *priv;
1149	int rc;
1150	void __iomem *addr;
1151
1152	rc = pci_enable_device(pdev);
1153	if (rc) {
1154		dev_err(&pdev->dev, "Failed pci_enable_device %d\n", rc);
1155		goto probe_exit_endev;
1156	}
1157
1158	rc = pci_request_regions(pdev, KBUILD_MODNAME);
1159	if (rc) {
1160		dev_err(&pdev->dev, "Failed pci_request_regions %d\n", rc);
1161		goto probe_exit_pcireq;
1162	}
1163
1164	addr = pci_iomap(pdev, 1, 0);
1165	if (!addr) {
1166		rc = -EIO;
1167		dev_err(&pdev->dev, "Failed pci_iomap\n");
1168		goto probe_exit_ipmap;
1169	}
1170
1171	ndev = alloc_candev(sizeof(struct pch_can_priv), PCH_TX_OBJ_END);
1172	if (!ndev) {
1173		rc = -ENOMEM;
1174		dev_err(&pdev->dev, "Failed alloc_candev\n");
1175		goto probe_exit_alloc_candev;
1176	}
1177
1178	priv = netdev_priv(ndev);
1179	priv->ndev = ndev;
1180	priv->regs = addr;
1181	priv->dev = pdev;
1182	priv->can.bittiming_const = &pch_can_bittiming_const;
1183	priv->can.do_set_mode = pch_can_do_set_mode;
1184	priv->can.do_get_berr_counter = pch_can_get_berr_counter;
1185	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
1186				       CAN_CTRLMODE_LOOPBACK;
1187	priv->tx_obj = PCH_TX_OBJ_START; /* Point head of Tx Obj */
1188
1189	ndev->irq = pdev->irq;
1190	ndev->flags |= IFF_ECHO;
1191
1192	pci_set_drvdata(pdev, ndev);
1193	SET_NETDEV_DEV(ndev, &pdev->dev);
1194	ndev->netdev_ops = &pch_can_netdev_ops;
1195	priv->can.clock.freq = PCH_CAN_CLK; /* Hz */
1196
1197	netif_napi_add(ndev, &priv->napi, pch_can_poll, PCH_RX_OBJ_END);
1198
1199	rc = pci_enable_msi(priv->dev);
1200	if (rc) {
1201		netdev_err(ndev, "PCH CAN opened without MSI\n");
1202		priv->use_msi = 0;
1203	} else {
1204		netdev_err(ndev, "PCH CAN opened with MSI\n");
1205		pci_set_master(pdev);
1206		priv->use_msi = 1;
1207	}
1208
1209	rc = register_candev(ndev);
1210	if (rc) {
1211		dev_err(&pdev->dev, "Failed register_candev %d\n", rc);
1212		goto probe_exit_reg_candev;
1213	}
1214
1215	return 0;
1216
1217probe_exit_reg_candev:
1218	if (priv->use_msi)
1219		pci_disable_msi(priv->dev);
1220	free_candev(ndev);
1221probe_exit_alloc_candev:
1222	pci_iounmap(pdev, addr);
1223probe_exit_ipmap:
1224	pci_release_regions(pdev);
1225probe_exit_pcireq:
1226	pci_disable_device(pdev);
1227probe_exit_endev:
1228	return rc;
1229}
1230
1231static SIMPLE_DEV_PM_OPS(pch_can_pm_ops,
1232			 pch_can_suspend,
1233			 pch_can_resume);
1234
1235static struct pci_driver pch_can_pci_driver = {
1236	.name = "pch_can",
1237	.id_table = pch_pci_tbl,
1238	.probe = pch_can_probe,
1239	.remove = pch_can_remove,
1240	.driver.pm = &pch_can_pm_ops,
1241};
1242
1243module_pci_driver(pch_can_pci_driver);
1244
1245MODULE_DESCRIPTION("Intel EG20T PCH CAN(Controller Area Network) Driver");
1246MODULE_LICENSE("GPL v2");
1247MODULE_VERSION("0.94");
   1/*
   2 * Copyright (C) 1999 - 2010 Intel Corporation.
   3 * Copyright (C) 2010 LAPIS SEMICONDUCTOR CO., LTD.
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License as published by
   7 * the Free Software Foundation; version 2 of the License.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18#include <linux/interrupt.h>
  19#include <linux/delay.h>
  20#include <linux/io.h>
  21#include <linux/module.h>
  22#include <linux/sched.h>
  23#include <linux/pci.h>
  24#include <linux/kernel.h>
  25#include <linux/types.h>
  26#include <linux/errno.h>
  27#include <linux/netdevice.h>
  28#include <linux/skbuff.h>
  29#include <linux/can.h>
  30#include <linux/can/dev.h>
  31#include <linux/can/error.h>
  32
  33#define PCH_CTRL_INIT		BIT(0) /* The INIT bit of CANCONT register. */
  34#define PCH_CTRL_IE		BIT(1) /* The IE bit of CAN control register */
  35#define PCH_CTRL_IE_SIE_EIE	(BIT(3) | BIT(2) | BIT(1))
  36#define PCH_CTRL_CCE		BIT(6)
  37#define PCH_CTRL_OPT		BIT(7) /* The OPT bit of CANCONT register. */
  38#define PCH_OPT_SILENT		BIT(3) /* The Silent bit of CANOPT reg. */
  39#define PCH_OPT_LBACK		BIT(4) /* The LoopBack bit of CANOPT reg. */
  40
  41#define PCH_CMASK_RX_TX_SET	0x00f3
  42#define PCH_CMASK_RX_TX_GET	0x0073
  43#define PCH_CMASK_ALL		0xff
  44#define PCH_CMASK_NEWDAT	BIT(2)
  45#define PCH_CMASK_CLRINTPND	BIT(3)
  46#define PCH_CMASK_CTRL		BIT(4)
  47#define PCH_CMASK_ARB		BIT(5)
  48#define PCH_CMASK_MASK		BIT(6)
  49#define PCH_CMASK_RDWR		BIT(7)
  50#define PCH_IF_MCONT_NEWDAT	BIT(15)
  51#define PCH_IF_MCONT_MSGLOST	BIT(14)
  52#define PCH_IF_MCONT_INTPND	BIT(13)
  53#define PCH_IF_MCONT_UMASK	BIT(12)
  54#define PCH_IF_MCONT_TXIE	BIT(11)
  55#define PCH_IF_MCONT_RXIE	BIT(10)
  56#define PCH_IF_MCONT_RMTEN	BIT(9)
  57#define PCH_IF_MCONT_TXRQXT	BIT(8)
  58#define PCH_IF_MCONT_EOB	BIT(7)
  59#define PCH_IF_MCONT_DLC	(BIT(0) | BIT(1) | BIT(2) | BIT(3))
  60#define PCH_MASK2_MDIR_MXTD	(BIT(14) | BIT(15))
  61#define PCH_ID2_DIR		BIT(13)
  62#define PCH_ID2_XTD		BIT(14)
  63#define PCH_ID_MSGVAL		BIT(15)
  64#define PCH_IF_CREQ_BUSY	BIT(15)
  65
  66#define PCH_STATUS_INT		0x8000
  67#define PCH_RP			0x00008000
  68#define PCH_REC			0x00007f00
  69#define PCH_TEC			0x000000ff
  70
  71#define PCH_TX_OK		BIT(3)
  72#define PCH_RX_OK		BIT(4)
  73#define PCH_EPASSIV		BIT(5)
  74#define PCH_EWARN		BIT(6)
  75#define PCH_BUS_OFF		BIT(7)
  76
  77/* bit position of certain controller bits. */
  78#define PCH_BIT_BRP_SHIFT	0
  79#define PCH_BIT_SJW_SHIFT	6
  80#define PCH_BIT_TSEG1_SHIFT	8
  81#define PCH_BIT_TSEG2_SHIFT	12
  82#define PCH_BIT_BRPE_BRPE_SHIFT	6
  83
  84#define PCH_MSK_BITT_BRP	0x3f
  85#define PCH_MSK_BRPE_BRPE	0x3c0
  86#define PCH_MSK_CTRL_IE_SIE_EIE	0x07
  87#define PCH_COUNTER_LIMIT	10
  88
  89#define PCH_CAN_CLK		50000000	/* 50MHz */
  90
  91/*
  92 * Define the number of message object.
  93 * PCH CAN communications are done via Message RAM.
  94 * The Message RAM consists of 32 message objects.
  95 */
  96#define PCH_RX_OBJ_NUM		26
  97#define PCH_TX_OBJ_NUM		6
  98#define PCH_RX_OBJ_START	1
  99#define PCH_RX_OBJ_END		PCH_RX_OBJ_NUM
 100#define PCH_TX_OBJ_START	(PCH_RX_OBJ_END + 1)
 101#define PCH_TX_OBJ_END		(PCH_RX_OBJ_NUM + PCH_TX_OBJ_NUM)
 102
 103#define PCH_FIFO_THRESH		16
 104
 105/* TxRqst2 show status of MsgObjNo.17~32 */
 106#define PCH_TREQ2_TX_MASK	(((1 << PCH_TX_OBJ_NUM) - 1) <<\
 107							(PCH_RX_OBJ_END - 16))
 108
 109enum pch_ifreg {
 110	PCH_RX_IFREG,
 111	PCH_TX_IFREG,
 112};
 113
 114enum pch_can_err {
 115	PCH_STUF_ERR = 1,
 116	PCH_FORM_ERR,
 117	PCH_ACK_ERR,
 118	PCH_BIT1_ERR,
 119	PCH_BIT0_ERR,
 120	PCH_CRC_ERR,
 121	PCH_LEC_ALL,
 122};
 123
 124enum pch_can_mode {
 125	PCH_CAN_ENABLE,
 126	PCH_CAN_DISABLE,
 127	PCH_CAN_ALL,
 128	PCH_CAN_NONE,
 129	PCH_CAN_STOP,
 130	PCH_CAN_RUN,
 131};
 132
 133struct pch_can_if_regs {
 134	u32 creq;
 135	u32 cmask;
 136	u32 mask1;
 137	u32 mask2;
 138	u32 id1;
 139	u32 id2;
 140	u32 mcont;
 141	u32 data[4];
 142	u32 rsv[13];
 143};
 144
 145struct pch_can_regs {
 146	u32 cont;
 147	u32 stat;
 148	u32 errc;
 149	u32 bitt;
 150	u32 intr;
 151	u32 opt;
 152	u32 brpe;
 153	u32 reserve;
 154	struct pch_can_if_regs ifregs[2]; /* [0]=if1  [1]=if2 */
 155	u32 reserve1[8];
 156	u32 treq1;
 157	u32 treq2;
 158	u32 reserve2[6];
 159	u32 data1;
 160	u32 data2;
 161	u32 reserve3[6];
 162	u32 canipend1;
 163	u32 canipend2;
 164	u32 reserve4[6];
 165	u32 canmval1;
 166	u32 canmval2;
 167	u32 reserve5[37];
 168	u32 srst;
 169};
 170
 171struct pch_can_priv {
 172	struct can_priv can;
 173	struct pci_dev *dev;
 174	u32 tx_enable[PCH_TX_OBJ_END];
 175	u32 rx_enable[PCH_TX_OBJ_END];
 176	u32 rx_link[PCH_TX_OBJ_END];
 177	u32 int_enables;
 178	struct net_device *ndev;
 179	struct pch_can_regs __iomem *regs;
 180	struct napi_struct napi;
 181	int tx_obj;	/* Point next Tx Obj index */
 182	int use_msi;
 183};
 184
 185static const struct can_bittiming_const pch_can_bittiming_const = {
 186	.name = KBUILD_MODNAME,
 187	.tseg1_min = 2,
 188	.tseg1_max = 16,
 189	.tseg2_min = 1,
 190	.tseg2_max = 8,
 191	.sjw_max = 4,
 192	.brp_min = 1,
 193	.brp_max = 1024, /* 6bit + extended 4bit */
 194	.brp_inc = 1,
 195};
 196
 197static const struct pci_device_id pch_pci_tbl[] = {
 198	{PCI_VENDOR_ID_INTEL, 0x8818, PCI_ANY_ID, PCI_ANY_ID,},
 199	{0,}
 200};
 201MODULE_DEVICE_TABLE(pci, pch_pci_tbl);
 202
 203static inline void pch_can_bit_set(void __iomem *addr, u32 mask)
 204{
 205	iowrite32(ioread32(addr) | mask, addr);
 206}
 207
 208static inline void pch_can_bit_clear(void __iomem *addr, u32 mask)
 209{
 210	iowrite32(ioread32(addr) & ~mask, addr);
 211}
 212
 213static void pch_can_set_run_mode(struct pch_can_priv *priv,
 214				 enum pch_can_mode mode)
 215{
 216	switch (mode) {
 217	case PCH_CAN_RUN:
 218		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_INIT);
 219		break;
 220
 221	case PCH_CAN_STOP:
 222		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_INIT);
 223		break;
 224
 225	default:
 226		netdev_err(priv->ndev, "%s -> Invalid Mode.\n", __func__);
 227		break;
 228	}
 229}
 230
 231static void pch_can_set_optmode(struct pch_can_priv *priv)
 232{
 233	u32 reg_val = ioread32(&priv->regs->opt);
 234
 235	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 236		reg_val |= PCH_OPT_SILENT;
 237
 238	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
 239		reg_val |= PCH_OPT_LBACK;
 240
 241	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_OPT);
 242	iowrite32(reg_val, &priv->regs->opt);
 243}
 244
 245static void pch_can_rw_msg_obj(void __iomem *creq_addr, u32 num)
 246{
 247	int counter = PCH_COUNTER_LIMIT;
 248	u32 ifx_creq;
 249
 250	iowrite32(num, creq_addr);
 251	while (counter) {
 252		ifx_creq = ioread32(creq_addr) & PCH_IF_CREQ_BUSY;
 253		if (!ifx_creq)
 254			break;
 255		counter--;
 256		udelay(1);
 257	}
 258	if (!counter)
 259		pr_err("%s:IF1 BUSY Flag is set forever.\n", __func__);
 260}
 261
 262static void pch_can_set_int_enables(struct pch_can_priv *priv,
 263				    enum pch_can_mode interrupt_no)
 264{
 265	switch (interrupt_no) {
 266	case PCH_CAN_DISABLE:
 267		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE);
 268		break;
 269
 270	case PCH_CAN_ALL:
 271		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 272		break;
 273
 274	case PCH_CAN_NONE:
 275		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 276		break;
 277
 278	default:
 279		netdev_err(priv->ndev, "Invalid interrupt number.\n");
 280		break;
 281	}
 282}
 283
 284static void pch_can_set_rxtx(struct pch_can_priv *priv, u32 buff_num,
 285			     int set, enum pch_ifreg dir)
 286{
 287	u32 ie;
 288
 289	if (dir)
 290		ie = PCH_IF_MCONT_TXIE;
 291	else
 292		ie = PCH_IF_MCONT_RXIE;
 293
 294	/* Reading the Msg buffer from Message RAM to IF1/2 registers. */
 295	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
 296	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 297
 298	/* Setting the IF1/2MASK1 register to access MsgVal and RxIE bits */
 299	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_ARB | PCH_CMASK_CTRL,
 300		  &priv->regs->ifregs[dir].cmask);
 301
 302	if (set) {
 303		/* Setting the MsgVal and RxIE/TxIE bits */
 304		pch_can_bit_set(&priv->regs->ifregs[dir].mcont, ie);
 305		pch_can_bit_set(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
 306	} else {
 307		/* Clearing the MsgVal and RxIE/TxIE bits */
 308		pch_can_bit_clear(&priv->regs->ifregs[dir].mcont, ie);
 309		pch_can_bit_clear(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
 310	}
 311
 312	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
 313}
 314
 315static void pch_can_set_rx_all(struct pch_can_priv *priv, int set)
 316{
 317	int i;
 318
 319	/* Traversing to obtain the object configured as receivers. */
 320	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++)
 321		pch_can_set_rxtx(priv, i, set, PCH_RX_IFREG);
 322}
 323
 324static void pch_can_set_tx_all(struct pch_can_priv *priv, int set)
 325{
 326	int i;
 327
 328	/* Traversing to obtain the object configured as transmit object. */
 329	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
 330		pch_can_set_rxtx(priv, i, set, PCH_TX_IFREG);
 331}
 332
 333static u32 pch_can_int_pending(struct pch_can_priv *priv)
 334{
 335	return ioread32(&priv->regs->intr) & 0xffff;
 336}
 337
 338static void pch_can_clear_if_buffers(struct pch_can_priv *priv)
 339{
 340	int i; /* Msg Obj ID (1~32) */
 341
 342	for (i = PCH_RX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
 343		iowrite32(PCH_CMASK_RX_TX_SET, &priv->regs->ifregs[0].cmask);
 344		iowrite32(0xffff, &priv->regs->ifregs[0].mask1);
 345		iowrite32(0xffff, &priv->regs->ifregs[0].mask2);
 346		iowrite32(0x0, &priv->regs->ifregs[0].id1);
 347		iowrite32(0x0, &priv->regs->ifregs[0].id2);
 348		iowrite32(0x0, &priv->regs->ifregs[0].mcont);
 349		iowrite32(0x0, &priv->regs->ifregs[0].data[0]);
 350		iowrite32(0x0, &priv->regs->ifregs[0].data[1]);
 351		iowrite32(0x0, &priv->regs->ifregs[0].data[2]);
 352		iowrite32(0x0, &priv->regs->ifregs[0].data[3]);
 353		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK |
 354			  PCH_CMASK_ARB | PCH_CMASK_CTRL,
 355			  &priv->regs->ifregs[0].cmask);
 356		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 357	}
 358}
 359
 360static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
 361{
 362	int i;
 363
 364	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
 365		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
 366		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 367
 368		iowrite32(0x0, &priv->regs->ifregs[0].id1);
 369		iowrite32(0x0, &priv->regs->ifregs[0].id2);
 370
 371		pch_can_bit_set(&priv->regs->ifregs[0].mcont,
 372				PCH_IF_MCONT_UMASK);
 373
 374		/* In case FIFO mode, Last EoB of Rx Obj must be 1 */
 375		if (i == PCH_RX_OBJ_END)
 376			pch_can_bit_set(&priv->regs->ifregs[0].mcont,
 377					PCH_IF_MCONT_EOB);
 378		else
 379			pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 380					  PCH_IF_MCONT_EOB);
 381
 382		iowrite32(0, &priv->regs->ifregs[0].mask1);
 383		pch_can_bit_clear(&priv->regs->ifregs[0].mask2,
 384				  0x1fff | PCH_MASK2_MDIR_MXTD);
 385
 386		/* Setting CMASK for writing */
 387		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
 388			  PCH_CMASK_CTRL, &priv->regs->ifregs[0].cmask);
 389
 390		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
 391	}
 392
 393	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
 394		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[1].cmask);
 395		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
 396
 397		/* Resetting DIR bit for reception */
 398		iowrite32(0x0, &priv->regs->ifregs[1].id1);
 399		iowrite32(PCH_ID2_DIR, &priv->regs->ifregs[1].id2);
 400
 401		/* Setting EOB bit for transmitter */
 402		iowrite32(PCH_IF_MCONT_EOB | PCH_IF_MCONT_UMASK,
 403			  &priv->regs->ifregs[1].mcont);
 404
 405		iowrite32(0, &priv->regs->ifregs[1].mask1);
 406		pch_can_bit_clear(&priv->regs->ifregs[1].mask2, 0x1fff);
 407
 408		/* Setting CMASK for writing */
 409		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
 410			  PCH_CMASK_CTRL, &priv->regs->ifregs[1].cmask);
 411
 412		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
 413	}
 414}
 415
 416static void pch_can_init(struct pch_can_priv *priv)
 417{
 418	/* Stopping the Can device. */
 419	pch_can_set_run_mode(priv, PCH_CAN_STOP);
 420
 421	/* Clearing all the message object buffers. */
 422	pch_can_clear_if_buffers(priv);
 423
 424	/* Configuring the respective message object as either rx/tx object. */
 425	pch_can_config_rx_tx_buffers(priv);
 426
 427	/* Enabling the interrupts. */
 428	pch_can_set_int_enables(priv, PCH_CAN_ALL);
 429}
 430
 431static void pch_can_release(struct pch_can_priv *priv)
 432{
 433	/* Stooping the CAN device. */
 434	pch_can_set_run_mode(priv, PCH_CAN_STOP);
 435
 436	/* Disabling the interrupts. */
 437	pch_can_set_int_enables(priv, PCH_CAN_NONE);
 438
 439	/* Disabling all the receive object. */
 440	pch_can_set_rx_all(priv, 0);
 441
 442	/* Disabling all the transmit object. */
 443	pch_can_set_tx_all(priv, 0);
 444}
 445
 446/* This function clears interrupt(s) from the CAN device. */
 447static void pch_can_int_clr(struct pch_can_priv *priv, u32 mask)
 448{
 449	/* Clear interrupt for transmit object */
 450	if ((mask >= PCH_RX_OBJ_START) && (mask <= PCH_RX_OBJ_END)) {
 451		/* Setting CMASK for clearing the reception interrupts. */
 452		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
 453			  &priv->regs->ifregs[0].cmask);
 454
 455		/* Clearing the Dir bit. */
 456		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
 457
 458		/* Clearing NewDat & IntPnd */
 459		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 460				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND);
 461
 462		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, mask);
 463	} else if ((mask >= PCH_TX_OBJ_START) && (mask <= PCH_TX_OBJ_END)) {
 464		/*
 465		 * Setting CMASK for clearing interrupts for frame transmission.
 466		 */
 467		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
 468			  &priv->regs->ifregs[1].cmask);
 469
 470		/* Resetting the ID registers. */
 471		pch_can_bit_set(&priv->regs->ifregs[1].id2,
 472			       PCH_ID2_DIR | (0x7ff << 2));
 473		iowrite32(0x0, &priv->regs->ifregs[1].id1);
 474
 475		/* Claring NewDat, TxRqst & IntPnd */
 476		pch_can_bit_clear(&priv->regs->ifregs[1].mcont,
 477				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND |
 478				  PCH_IF_MCONT_TXRQXT);
 479		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, mask);
 480	}
 481}
 482
 483static void pch_can_reset(struct pch_can_priv *priv)
 484{
 485	/* write to sw reset register */
 486	iowrite32(1, &priv->regs->srst);
 487	iowrite32(0, &priv->regs->srst);
 488}
 489
 490static void pch_can_error(struct net_device *ndev, u32 status)
 491{
 492	struct sk_buff *skb;
 493	struct pch_can_priv *priv = netdev_priv(ndev);
 494	struct can_frame *cf;
 495	u32 errc, lec;
 496	struct net_device_stats *stats = &(priv->ndev->stats);
 497	enum can_state state = priv->can.state;
 498
 499	skb = alloc_can_err_skb(ndev, &cf);
 500	if (!skb)
 501		return;
 502
 503	if (status & PCH_BUS_OFF) {
 504		pch_can_set_tx_all(priv, 0);
 505		pch_can_set_rx_all(priv, 0);
 506		state = CAN_STATE_BUS_OFF;
 507		cf->can_id |= CAN_ERR_BUSOFF;
 508		priv->can.can_stats.bus_off++;
 509		can_bus_off(ndev);
 510	}
 511
 512	errc = ioread32(&priv->regs->errc);
 513	/* Warning interrupt. */
 514	if (status & PCH_EWARN) {
 515		state = CAN_STATE_ERROR_WARNING;
 516		priv->can.can_stats.error_warning++;
 517		cf->can_id |= CAN_ERR_CRTL;
 518		if (((errc & PCH_REC) >> 8) > 96)
 519			cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
 520		if ((errc & PCH_TEC) > 96)
 521			cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
 522		netdev_dbg(ndev,
 523			"%s -> Error Counter is more than 96.\n", __func__);
 524	}
 525	/* Error passive interrupt. */
 526	if (status & PCH_EPASSIV) {
 527		priv->can.can_stats.error_passive++;
 528		state = CAN_STATE_ERROR_PASSIVE;
 529		cf->can_id |= CAN_ERR_CRTL;
 530		if (errc & PCH_RP)
 531			cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
 532		if ((errc & PCH_TEC) > 127)
 533			cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
 534		netdev_dbg(ndev,
 535			"%s -> CAN controller is ERROR PASSIVE .\n", __func__);
 536	}
 537
 538	lec = status & PCH_LEC_ALL;
 539	switch (lec) {
 540	case PCH_STUF_ERR:
 541		cf->data[2] |= CAN_ERR_PROT_STUFF;
 542		priv->can.can_stats.bus_error++;
 543		stats->rx_errors++;
 544		break;
 545	case PCH_FORM_ERR:
 546		cf->data[2] |= CAN_ERR_PROT_FORM;
 547		priv->can.can_stats.bus_error++;
 548		stats->rx_errors++;
 549		break;
 550	case PCH_ACK_ERR:
 551		cf->can_id |= CAN_ERR_ACK;
 552		priv->can.can_stats.bus_error++;
 553		stats->rx_errors++;
 554		break;
 555	case PCH_BIT1_ERR:
 556	case PCH_BIT0_ERR:
 557		cf->data[2] |= CAN_ERR_PROT_BIT;
 558		priv->can.can_stats.bus_error++;
 559		stats->rx_errors++;
 560		break;
 561	case PCH_CRC_ERR:
 562		cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
 563		priv->can.can_stats.bus_error++;
 564		stats->rx_errors++;
 565		break;
 566	case PCH_LEC_ALL: /* Written by CPU. No error status */
 567		break;
 568	}
 569
 570	cf->data[6] = errc & PCH_TEC;
 571	cf->data[7] = (errc & PCH_REC) >> 8;
 572
 573	priv->can.state = state;
 574	netif_receive_skb(skb);
 575
 576	stats->rx_packets++;
 577	stats->rx_bytes += cf->can_dlc;
 578}
 579
 580static irqreturn_t pch_can_interrupt(int irq, void *dev_id)
 581{
 582	struct net_device *ndev = (struct net_device *)dev_id;
 583	struct pch_can_priv *priv = netdev_priv(ndev);
 584
 585	if (!pch_can_int_pending(priv))
 586		return IRQ_NONE;
 587
 588	pch_can_set_int_enables(priv, PCH_CAN_NONE);
 589	napi_schedule(&priv->napi);
 590	return IRQ_HANDLED;
 591}
 592
 593static void pch_fifo_thresh(struct pch_can_priv *priv, int obj_id)
 594{
 595	if (obj_id < PCH_FIFO_THRESH) {
 596		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL |
 597			  PCH_CMASK_ARB, &priv->regs->ifregs[0].cmask);
 598
 599		/* Clearing the Dir bit. */
 600		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
 601
 602		/* Clearing NewDat & IntPnd */
 603		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 604				  PCH_IF_MCONT_INTPND);
 605		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
 606	} else if (obj_id > PCH_FIFO_THRESH) {
 607		pch_can_int_clr(priv, obj_id);
 608	} else if (obj_id == PCH_FIFO_THRESH) {
 609		int cnt;
 610		for (cnt = 0; cnt < PCH_FIFO_THRESH; cnt++)
 611			pch_can_int_clr(priv, cnt + 1);
 612	}
 613}
 614
 615static void pch_can_rx_msg_lost(struct net_device *ndev, int obj_id)
 616{
 617	struct pch_can_priv *priv = netdev_priv(ndev);
 618	struct net_device_stats *stats = &(priv->ndev->stats);
 619	struct sk_buff *skb;
 620	struct can_frame *cf;
 621
 622	netdev_dbg(priv->ndev, "Msg Obj is overwritten.\n");
 623	pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
 624			  PCH_IF_MCONT_MSGLOST);
 625	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
 626		  &priv->regs->ifregs[0].cmask);
 627	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
 628
 629	skb = alloc_can_err_skb(ndev, &cf);
 630	if (!skb)
 631		return;
 632
 633	cf->can_id |= CAN_ERR_CRTL;
 634	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 635	stats->rx_over_errors++;
 636	stats->rx_errors++;
 637
 638	netif_receive_skb(skb);
 639}
 640
 641static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota)
 642{
 643	u32 reg;
 644	canid_t id;
 645	int rcv_pkts = 0;
 646	struct sk_buff *skb;
 647	struct can_frame *cf;
 648	struct pch_can_priv *priv = netdev_priv(ndev);
 649	struct net_device_stats *stats = &(priv->ndev->stats);
 650	int i;
 651	u32 id2;
 652	u16 data_reg;
 653
 654	do {
 655		/* Reading the message object from the Message RAM */
 656		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
 657		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_num);
 658
 659		/* Reading the MCONT register. */
 660		reg = ioread32(&priv->regs->ifregs[0].mcont);
 661
 662		if (reg & PCH_IF_MCONT_EOB)
 663			break;
 664
 665		/* If MsgLost bit set. */
 666		if (reg & PCH_IF_MCONT_MSGLOST) {
 667			pch_can_rx_msg_lost(ndev, obj_num);
 668			rcv_pkts++;
 669			quota--;
 670			obj_num++;
 671			continue;
 672		} else if (!(reg & PCH_IF_MCONT_NEWDAT)) {
 673			obj_num++;
 674			continue;
 675		}
 676
 677		skb = alloc_can_skb(priv->ndev, &cf);
 678		if (!skb) {
 679			netdev_err(ndev, "alloc_can_skb Failed\n");
 680			return rcv_pkts;
 681		}
 682
 683		/* Get Received data */
 684		id2 = ioread32(&priv->regs->ifregs[0].id2);
 685		if (id2 & PCH_ID2_XTD) {
 686			id = (ioread32(&priv->regs->ifregs[0].id1) & 0xffff);
 687			id |= (((id2) & 0x1fff) << 16);
 688			cf->can_id = id | CAN_EFF_FLAG;
 689		} else {
 690			id = (id2 >> 2) & CAN_SFF_MASK;
 691			cf->can_id = id;
 692		}
 693
 694		if (id2 & PCH_ID2_DIR)
 695			cf->can_id |= CAN_RTR_FLAG;
 696
 697		cf->can_dlc = get_can_dlc((ioread32(&priv->regs->
 698						    ifregs[0].mcont)) & 0xF);
 699
 700		for (i = 0; i < cf->can_dlc; i += 2) {
 701			data_reg = ioread16(&priv->regs->ifregs[0].data[i / 2]);
 702			cf->data[i] = data_reg;
 703			cf->data[i + 1] = data_reg >> 8;
 704		}
 705
 706		netif_receive_skb(skb);
 707		rcv_pkts++;
 708		stats->rx_packets++;
 709		quota--;
 710		stats->rx_bytes += cf->can_dlc;
 711
 712		pch_fifo_thresh(priv, obj_num);
 713		obj_num++;
 714	} while (quota > 0);
 715
 716	return rcv_pkts;
 717}
 718
 719static void pch_can_tx_complete(struct net_device *ndev, u32 int_stat)
 720{
 721	struct pch_can_priv *priv = netdev_priv(ndev);
 722	struct net_device_stats *stats = &(priv->ndev->stats);
 723	u32 dlc;
 724
 725	can_get_echo_skb(ndev, int_stat - PCH_RX_OBJ_END - 1);
 726	iowrite32(PCH_CMASK_RX_TX_GET | PCH_CMASK_CLRINTPND,
 727		  &priv->regs->ifregs[1].cmask);
 728	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, int_stat);
 729	dlc = get_can_dlc(ioread32(&priv->regs->ifregs[1].mcont) &
 730			  PCH_IF_MCONT_DLC);
 731	stats->tx_bytes += dlc;
 732	stats->tx_packets++;
 733	if (int_stat == PCH_TX_OBJ_END)
 734		netif_wake_queue(ndev);
 735}
 736
 737static int pch_can_poll(struct napi_struct *napi, int quota)
 738{
 739	struct net_device *ndev = napi->dev;
 740	struct pch_can_priv *priv = netdev_priv(ndev);
 741	u32 int_stat;
 742	u32 reg_stat;
 743	int quota_save = quota;
 744
 745	int_stat = pch_can_int_pending(priv);
 746	if (!int_stat)
 747		goto end;
 748
 749	if (int_stat == PCH_STATUS_INT) {
 750		reg_stat = ioread32(&priv->regs->stat);
 751
 752		if ((reg_stat & (PCH_BUS_OFF | PCH_LEC_ALL)) &&
 753		   ((reg_stat & PCH_LEC_ALL) != PCH_LEC_ALL)) {
 754			pch_can_error(ndev, reg_stat);
 755			quota--;
 756		}
 757
 758		if (reg_stat & (PCH_TX_OK | PCH_RX_OK))
 759			pch_can_bit_clear(&priv->regs->stat,
 760					  reg_stat & (PCH_TX_OK | PCH_RX_OK));
 761
 762		int_stat = pch_can_int_pending(priv);
 763	}
 764
 765	if (quota == 0)
 766		goto end;
 767
 768	if ((int_stat >= PCH_RX_OBJ_START) && (int_stat <= PCH_RX_OBJ_END)) {
 769		quota -= pch_can_rx_normal(ndev, int_stat, quota);
 770	} else if ((int_stat >= PCH_TX_OBJ_START) &&
 771		   (int_stat <= PCH_TX_OBJ_END)) {
 772		/* Handle transmission interrupt */
 773		pch_can_tx_complete(ndev, int_stat);
 774	}
 775
 776end:
 777	napi_complete(napi);
 778	pch_can_set_int_enables(priv, PCH_CAN_ALL);
 779
 780	return quota_save - quota;
 781}
 782
 783static int pch_set_bittiming(struct net_device *ndev)
 784{
 785	struct pch_can_priv *priv = netdev_priv(ndev);
 786	const struct can_bittiming *bt = &priv->can.bittiming;
 787	u32 canbit;
 788	u32 bepe;
 789
 790	/* Setting the CCE bit for accessing the Can Timing register. */
 791	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_CCE);
 792
 793	canbit = (bt->brp - 1) & PCH_MSK_BITT_BRP;
 794	canbit |= (bt->sjw - 1) << PCH_BIT_SJW_SHIFT;
 795	canbit |= (bt->phase_seg1 + bt->prop_seg - 1) << PCH_BIT_TSEG1_SHIFT;
 796	canbit |= (bt->phase_seg2 - 1) << PCH_BIT_TSEG2_SHIFT;
 797	bepe = ((bt->brp - 1) & PCH_MSK_BRPE_BRPE) >> PCH_BIT_BRPE_BRPE_SHIFT;
 798	iowrite32(canbit, &priv->regs->bitt);
 799	iowrite32(bepe, &priv->regs->brpe);
 800	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_CCE);
 801
 802	return 0;
 803}
 804
 805static void pch_can_start(struct net_device *ndev)
 806{
 807	struct pch_can_priv *priv = netdev_priv(ndev);
 808
 809	if (priv->can.state != CAN_STATE_STOPPED)
 810		pch_can_reset(priv);
 811
 812	pch_set_bittiming(ndev);
 813	pch_can_set_optmode(priv);
 814
 815	pch_can_set_tx_all(priv, 1);
 816	pch_can_set_rx_all(priv, 1);
 817
 818	/* Setting the CAN to run mode. */
 819	pch_can_set_run_mode(priv, PCH_CAN_RUN);
 820
 821	priv->can.state = CAN_STATE_ERROR_ACTIVE;
 822
 823	return;
 824}
 825
 826static int pch_can_do_set_mode(struct net_device *ndev, enum can_mode mode)
 827{
 828	int ret = 0;
 829
 830	switch (mode) {
 831	case CAN_MODE_START:
 832		pch_can_start(ndev);
 833		netif_wake_queue(ndev);
 834		break;
 835	default:
 836		ret = -EOPNOTSUPP;
 837		break;
 838	}
 839
 840	return ret;
 841}
 842
 843static int pch_can_open(struct net_device *ndev)
 844{
 845	struct pch_can_priv *priv = netdev_priv(ndev);
 846	int retval;
 847
 848	/* Regstering the interrupt. */
 849	retval = request_irq(priv->dev->irq, pch_can_interrupt, IRQF_SHARED,
 850			     ndev->name, ndev);
 851	if (retval) {
 852		netdev_err(ndev, "request_irq failed.\n");
 853		goto req_irq_err;
 854	}
 855
 856	/* Open common can device */
 857	retval = open_candev(ndev);
 858	if (retval) {
 859		netdev_err(ndev, "open_candev() failed %d\n", retval);
 860		goto err_open_candev;
 861	}
 862
 863	pch_can_init(priv);
 864	pch_can_start(ndev);
 865	napi_enable(&priv->napi);
 866	netif_start_queue(ndev);
 867
 868	return 0;
 869
 870err_open_candev:
 871	free_irq(priv->dev->irq, ndev);
 872req_irq_err:
 873	pch_can_release(priv);
 874
 875	return retval;
 876}
 877
 878static int pch_close(struct net_device *ndev)
 879{
 880	struct pch_can_priv *priv = netdev_priv(ndev);
 881
 882	netif_stop_queue(ndev);
 883	napi_disable(&priv->napi);
 884	pch_can_release(priv);
 885	free_irq(priv->dev->irq, ndev);
 886	close_candev(ndev);
 887	priv->can.state = CAN_STATE_STOPPED;
 888	return 0;
 889}
 890
 891static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
 892{
 893	struct pch_can_priv *priv = netdev_priv(ndev);
 894	struct can_frame *cf = (struct can_frame *)skb->data;
 895	int tx_obj_no;
 896	int i;
 897	u32 id2;
 898
 899	if (can_dropped_invalid_skb(ndev, skb))
 900		return NETDEV_TX_OK;
 901
 902	tx_obj_no = priv->tx_obj;
 903	if (priv->tx_obj == PCH_TX_OBJ_END) {
 904		if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK)
 905			netif_stop_queue(ndev);
 906
 907		priv->tx_obj = PCH_TX_OBJ_START;
 908	} else {
 909		priv->tx_obj++;
 910	}
 911
 912	/* Setting the CMASK register. */
 913	pch_can_bit_set(&priv->regs->ifregs[1].cmask, PCH_CMASK_ALL);
 914
 915	/* If ID extended is set. */
 916	if (cf->can_id & CAN_EFF_FLAG) {
 917		iowrite32(cf->can_id & 0xffff, &priv->regs->ifregs[1].id1);
 918		id2 = ((cf->can_id >> 16) & 0x1fff) | PCH_ID2_XTD;
 919	} else {
 920		iowrite32(0, &priv->regs->ifregs[1].id1);
 921		id2 = (cf->can_id & CAN_SFF_MASK) << 2;
 922	}
 923
 924	id2 |= PCH_ID_MSGVAL;
 925
 926	/* If remote frame has to be transmitted.. */
 927	if (!(cf->can_id & CAN_RTR_FLAG))
 928		id2 |= PCH_ID2_DIR;
 929
 930	iowrite32(id2, &priv->regs->ifregs[1].id2);
 931
 932	/* Copy data to register */
 933	for (i = 0; i < cf->can_dlc; i += 2) {
 934		iowrite16(cf->data[i] | (cf->data[i + 1] << 8),
 935			  &priv->regs->ifregs[1].data[i / 2]);
 936	}
 937
 938	can_put_echo_skb(skb, ndev, tx_obj_no - PCH_RX_OBJ_END - 1);
 939
 940	/* Set the size of the data. Update if2_mcont */
 941	iowrite32(cf->can_dlc | PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_TXRQXT |
 942		  PCH_IF_MCONT_TXIE, &priv->regs->ifregs[1].mcont);
 943
 944	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no);
 945
 946	return NETDEV_TX_OK;
 947}
 948
 949static const struct net_device_ops pch_can_netdev_ops = {
 950	.ndo_open		= pch_can_open,
 951	.ndo_stop		= pch_close,
 952	.ndo_start_xmit		= pch_xmit,
 953	.ndo_change_mtu		= can_change_mtu,
 954};
 955
 956static void pch_can_remove(struct pci_dev *pdev)
 957{
 958	struct net_device *ndev = pci_get_drvdata(pdev);
 959	struct pch_can_priv *priv = netdev_priv(ndev);
 960
 961	unregister_candev(priv->ndev);
 962	if (priv->use_msi)
 963		pci_disable_msi(priv->dev);
 964	pci_release_regions(pdev);
 965	pci_disable_device(pdev);
 966	pch_can_reset(priv);
 967	pci_iounmap(pdev, priv->regs);
 968	free_candev(priv->ndev);
 969}
 970
 971#ifdef CONFIG_PM
 972static void pch_can_set_int_custom(struct pch_can_priv *priv)
 973{
 974	/* Clearing the IE, SIE and EIE bits of Can control register. */
 975	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
 976
 977	/* Appropriately setting them. */
 978	pch_can_bit_set(&priv->regs->cont,
 979			((priv->int_enables & PCH_MSK_CTRL_IE_SIE_EIE) << 1));
 980}
 981
 982/* This function retrieves interrupt enabled for the CAN device. */
 983static u32 pch_can_get_int_enables(struct pch_can_priv *priv)
 984{
 985	/* Obtaining the status of IE, SIE and EIE interrupt bits. */
 986	return (ioread32(&priv->regs->cont) & PCH_CTRL_IE_SIE_EIE) >> 1;
 987}
 988
 989static u32 pch_can_get_rxtx_ir(struct pch_can_priv *priv, u32 buff_num,
 990			       enum pch_ifreg dir)
 991{
 992	u32 ie, enable;
 993
 994	if (dir)
 995		ie = PCH_IF_MCONT_RXIE;
 996	else
 997		ie = PCH_IF_MCONT_TXIE;
 998
 999	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
1000	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
1001
1002	if (((ioread32(&priv->regs->ifregs[dir].id2)) & PCH_ID_MSGVAL) &&
1003			((ioread32(&priv->regs->ifregs[dir].mcont)) & ie))
1004		enable = 1;
1005	else
1006		enable = 0;
1007
1008	return enable;
1009}
1010
1011static void pch_can_set_rx_buffer_link(struct pch_can_priv *priv,
1012				       u32 buffer_num, int set)
1013{
1014	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1015	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1016	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
1017		  &priv->regs->ifregs[0].cmask);
1018	if (set)
1019		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
1020				  PCH_IF_MCONT_EOB);
1021	else
1022		pch_can_bit_set(&priv->regs->ifregs[0].mcont, PCH_IF_MCONT_EOB);
1023
1024	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1025}
1026
1027static u32 pch_can_get_rx_buffer_link(struct pch_can_priv *priv, u32 buffer_num)
1028{
1029	u32 link;
1030
1031	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1032	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1033
1034	if (ioread32(&priv->regs->ifregs[0].mcont) & PCH_IF_MCONT_EOB)
1035		link = 0;
1036	else
1037		link = 1;
1038	return link;
1039}
1040
1041static int pch_can_get_buffer_status(struct pch_can_priv *priv)
1042{
1043	return (ioread32(&priv->regs->treq1) & 0xffff) |
1044	       (ioread32(&priv->regs->treq2) << 16);
1045}
1046
1047static int pch_can_suspend(struct pci_dev *pdev, pm_message_t state)
1048{
1049	int i;
1050	int retval;
1051	u32 buf_stat;	/* Variable for reading the transmit buffer status. */
1052	int counter = PCH_COUNTER_LIMIT;
1053
1054	struct net_device *dev = pci_get_drvdata(pdev);
1055	struct pch_can_priv *priv = netdev_priv(dev);
1056
1057	/* Stop the CAN controller */
1058	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1059
1060	/* Indicate that we are aboutto/in suspend */
1061	priv->can.state = CAN_STATE_STOPPED;
1062
1063	/* Waiting for all transmission to complete. */
1064	while (counter) {
1065		buf_stat = pch_can_get_buffer_status(priv);
1066		if (!buf_stat)
1067			break;
1068		counter--;
1069		udelay(1);
1070	}
1071	if (!counter)
1072		dev_err(&pdev->dev, "%s -> Transmission time out.\n", __func__);
1073
1074	/* Save interrupt configuration and then disable them */
1075	priv->int_enables = pch_can_get_int_enables(priv);
1076	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1077
1078	/* Save Tx buffer enable state */
1079	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1080		priv->tx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1081							     PCH_TX_IFREG);
1082
1083	/* Disable all Transmit buffers */
1084	pch_can_set_tx_all(priv, 0);
1085
1086	/* Save Rx buffer enable state */
1087	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1088		priv->rx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1089							     PCH_RX_IFREG);
1090		priv->rx_link[i - 1] = pch_can_get_rx_buffer_link(priv, i);
1091	}
1092
1093	/* Disable all Receive buffers */
1094	pch_can_set_rx_all(priv, 0);
1095	retval = pci_save_state(pdev);
1096	if (retval) {
1097		dev_err(&pdev->dev, "pci_save_state failed.\n");
1098	} else {
1099		pci_enable_wake(pdev, PCI_D3hot, 0);
1100		pci_disable_device(pdev);
1101		pci_set_power_state(pdev, pci_choose_state(pdev, state));
1102	}
1103
1104	return retval;
1105}
1106
1107static int pch_can_resume(struct pci_dev *pdev)
1108{
1109	int i;
1110	int retval;
1111	struct net_device *dev = pci_get_drvdata(pdev);
1112	struct pch_can_priv *priv = netdev_priv(dev);
1113
1114	pci_set_power_state(pdev, PCI_D0);
1115	pci_restore_state(pdev);
1116	retval = pci_enable_device(pdev);
1117	if (retval) {
1118		dev_err(&pdev->dev, "pci_enable_device failed.\n");
1119		return retval;
1120	}
1121
1122	pci_enable_wake(pdev, PCI_D3hot, 0);
1123
1124	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1125
1126	/* Disabling all interrupts. */
1127	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1128
1129	/* Setting the CAN device in Stop Mode. */
1130	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1131
1132	/* Configuring the transmit and receive buffers. */
1133	pch_can_config_rx_tx_buffers(priv);
1134
1135	/* Restore the CAN state */
1136	pch_set_bittiming(dev);
1137
1138	/* Listen/Active */
1139	pch_can_set_optmode(priv);
1140
1141	/* Enabling the transmit buffer. */
1142	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1143		pch_can_set_rxtx(priv, i, priv->tx_enable[i - 1], PCH_TX_IFREG);
1144
1145	/* Configuring the receive buffer and enabling them. */
1146	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1147		/* Restore buffer link */
1148		pch_can_set_rx_buffer_link(priv, i, priv->rx_link[i - 1]);
1149
1150		/* Restore buffer enables */
1151		pch_can_set_rxtx(priv, i, priv->rx_enable[i - 1], PCH_RX_IFREG);
1152	}
1153
1154	/* Enable CAN Interrupts */
1155	pch_can_set_int_custom(priv);
1156
1157	/* Restore Run Mode */
1158	pch_can_set_run_mode(priv, PCH_CAN_RUN);
1159
1160	return retval;
1161}
1162#else
1163#define pch_can_suspend NULL
1164#define pch_can_resume NULL
1165#endif
1166
1167static int pch_can_get_berr_counter(const struct net_device *dev,
1168				    struct can_berr_counter *bec)
1169{
1170	struct pch_can_priv *priv = netdev_priv(dev);
1171	u32 errc = ioread32(&priv->regs->errc);
1172
1173	bec->txerr = errc & PCH_TEC;
1174	bec->rxerr = (errc & PCH_REC) >> 8;
1175
1176	return 0;
1177}
1178
1179static int pch_can_probe(struct pci_dev *pdev,
1180				   const struct pci_device_id *id)
1181{
1182	struct net_device *ndev;
1183	struct pch_can_priv *priv;
1184	int rc;
1185	void __iomem *addr;
1186
1187	rc = pci_enable_device(pdev);
1188	if (rc) {
1189		dev_err(&pdev->dev, "Failed pci_enable_device %d\n", rc);
1190		goto probe_exit_endev;
1191	}
1192
1193	rc = pci_request_regions(pdev, KBUILD_MODNAME);
1194	if (rc) {
1195		dev_err(&pdev->dev, "Failed pci_request_regions %d\n", rc);
1196		goto probe_exit_pcireq;
1197	}
1198
1199	addr = pci_iomap(pdev, 1, 0);
1200	if (!addr) {
1201		rc = -EIO;
1202		dev_err(&pdev->dev, "Failed pci_iomap\n");
1203		goto probe_exit_ipmap;
1204	}
1205
1206	ndev = alloc_candev(sizeof(struct pch_can_priv), PCH_TX_OBJ_END);
1207	if (!ndev) {
1208		rc = -ENOMEM;
1209		dev_err(&pdev->dev, "Failed alloc_candev\n");
1210		goto probe_exit_alloc_candev;
1211	}
1212
1213	priv = netdev_priv(ndev);
1214	priv->ndev = ndev;
1215	priv->regs = addr;
1216	priv->dev = pdev;
1217	priv->can.bittiming_const = &pch_can_bittiming_const;
1218	priv->can.do_set_mode = pch_can_do_set_mode;
1219	priv->can.do_get_berr_counter = pch_can_get_berr_counter;
1220	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
1221				       CAN_CTRLMODE_LOOPBACK;
1222	priv->tx_obj = PCH_TX_OBJ_START; /* Point head of Tx Obj */
1223
1224	ndev->irq = pdev->irq;
1225	ndev->flags |= IFF_ECHO;
1226
1227	pci_set_drvdata(pdev, ndev);
1228	SET_NETDEV_DEV(ndev, &pdev->dev);
1229	ndev->netdev_ops = &pch_can_netdev_ops;
1230	priv->can.clock.freq = PCH_CAN_CLK; /* Hz */
1231
1232	netif_napi_add(ndev, &priv->napi, pch_can_poll, PCH_RX_OBJ_END);
1233
1234	rc = pci_enable_msi(priv->dev);
1235	if (rc) {
1236		netdev_err(ndev, "PCH CAN opened without MSI\n");
1237		priv->use_msi = 0;
1238	} else {
1239		netdev_err(ndev, "PCH CAN opened with MSI\n");
1240		pci_set_master(pdev);
1241		priv->use_msi = 1;
1242	}
1243
1244	rc = register_candev(ndev);
1245	if (rc) {
1246		dev_err(&pdev->dev, "Failed register_candev %d\n", rc);
1247		goto probe_exit_reg_candev;
1248	}
1249
1250	return 0;
1251
1252probe_exit_reg_candev:
1253	if (priv->use_msi)
1254		pci_disable_msi(priv->dev);
1255	free_candev(ndev);
1256probe_exit_alloc_candev:
1257	pci_iounmap(pdev, addr);
1258probe_exit_ipmap:
1259	pci_release_regions(pdev);
1260probe_exit_pcireq:
1261	pci_disable_device(pdev);
1262probe_exit_endev:
1263	return rc;
1264}
1265
1266static struct pci_driver pch_can_pci_driver = {
1267	.name = "pch_can",
1268	.id_table = pch_pci_tbl,
1269	.probe = pch_can_probe,
1270	.remove = pch_can_remove,
1271	.suspend = pch_can_suspend,
1272	.resume = pch_can_resume,
1273};
1274
1275module_pci_driver(pch_can_pci_driver);
1276
1277MODULE_DESCRIPTION("Intel EG20T PCH CAN(Controller Area Network) Driver");
1278MODULE_LICENSE("GPL v2");
1279MODULE_VERSION("0.94");