linux/drivers/net/can/m_can/m_can.c
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   1/*
   2 * CAN bus driver for Bosch M_CAN controller
   3 *
   4 * Copyright (C) 2014 Freescale Semiconductor, Inc.
   5 *      Dong Aisheng <b29396@freescale.com>
   6 *
   7 * Bosch M_CAN user manual can be obtained from:
   8 * http://www.bosch-semiconductors.de/media/pdf_1/ipmodules_1/m_can/
   9 * mcan_users_manual_v302.pdf
  10 *
  11 * This file is licensed under the terms of the GNU General Public
  12 * License version 2. This program is licensed "as is" without any
  13 * warranty of any kind, whether express or implied.
  14 */
  15
  16#include <linux/clk.h>
  17#include <linux/delay.h>
  18#include <linux/interrupt.h>
  19#include <linux/io.h>
  20#include <linux/kernel.h>
  21#include <linux/module.h>
  22#include <linux/netdevice.h>
  23#include <linux/of.h>
  24#include <linux/of_device.h>
  25#include <linux/platform_device.h>
  26
  27#include <linux/can/dev.h>
  28
  29/* napi related */
  30#define M_CAN_NAPI_WEIGHT       64
  31
  32/* message ram configuration data length */
  33#define MRAM_CFG_LEN    8
  34
  35/* registers definition */
  36enum m_can_reg {
  37        M_CAN_CREL      = 0x0,
  38        M_CAN_ENDN      = 0x4,
  39        M_CAN_CUST      = 0x8,
  40        M_CAN_FBTP      = 0xc,
  41        M_CAN_TEST      = 0x10,
  42        M_CAN_RWD       = 0x14,
  43        M_CAN_CCCR      = 0x18,
  44        M_CAN_BTP       = 0x1c,
  45        M_CAN_TSCC      = 0x20,
  46        M_CAN_TSCV      = 0x24,
  47        M_CAN_TOCC      = 0x28,
  48        M_CAN_TOCV      = 0x2c,
  49        M_CAN_ECR       = 0x40,
  50        M_CAN_PSR       = 0x44,
  51        M_CAN_IR        = 0x50,
  52        M_CAN_IE        = 0x54,
  53        M_CAN_ILS       = 0x58,
  54        M_CAN_ILE       = 0x5c,
  55        M_CAN_GFC       = 0x80,
  56        M_CAN_SIDFC     = 0x84,
  57        M_CAN_XIDFC     = 0x88,
  58        M_CAN_XIDAM     = 0x90,
  59        M_CAN_HPMS      = 0x94,
  60        M_CAN_NDAT1     = 0x98,
  61        M_CAN_NDAT2     = 0x9c,
  62        M_CAN_RXF0C     = 0xa0,
  63        M_CAN_RXF0S     = 0xa4,
  64        M_CAN_RXF0A     = 0xa8,
  65        M_CAN_RXBC      = 0xac,
  66        M_CAN_RXF1C     = 0xb0,
  67        M_CAN_RXF1S     = 0xb4,
  68        M_CAN_RXF1A     = 0xb8,
  69        M_CAN_RXESC     = 0xbc,
  70        M_CAN_TXBC      = 0xc0,
  71        M_CAN_TXFQS     = 0xc4,
  72        M_CAN_TXESC     = 0xc8,
  73        M_CAN_TXBRP     = 0xcc,
  74        M_CAN_TXBAR     = 0xd0,
  75        M_CAN_TXBCR     = 0xd4,
  76        M_CAN_TXBTO     = 0xd8,
  77        M_CAN_TXBCF     = 0xdc,
  78        M_CAN_TXBTIE    = 0xe0,
  79        M_CAN_TXBCIE    = 0xe4,
  80        M_CAN_TXEFC     = 0xf0,
  81        M_CAN_TXEFS     = 0xf4,
  82        M_CAN_TXEFA     = 0xf8,
  83};
  84
  85/* m_can lec values */
  86enum m_can_lec_type {
  87        LEC_NO_ERROR = 0,
  88        LEC_STUFF_ERROR,
  89        LEC_FORM_ERROR,
  90        LEC_ACK_ERROR,
  91        LEC_BIT1_ERROR,
  92        LEC_BIT0_ERROR,
  93        LEC_CRC_ERROR,
  94        LEC_UNUSED,
  95};
  96
  97enum m_can_mram_cfg {
  98        MRAM_SIDF = 0,
  99        MRAM_XIDF,
 100        MRAM_RXF0,
 101        MRAM_RXF1,
 102        MRAM_RXB,
 103        MRAM_TXE,
 104        MRAM_TXB,
 105        MRAM_CFG_NUM,
 106};
 107
 108/* Fast Bit Timing & Prescaler Register (FBTP) */
 109#define FBTR_FBRP_MASK          0x1f
 110#define FBTR_FBRP_SHIFT         16
 111#define FBTR_FTSEG1_SHIFT       8
 112#define FBTR_FTSEG1_MASK        (0xf << FBTR_FTSEG1_SHIFT)
 113#define FBTR_FTSEG2_SHIFT       4
 114#define FBTR_FTSEG2_MASK        (0x7 << FBTR_FTSEG2_SHIFT)
 115#define FBTR_FSJW_SHIFT         0
 116#define FBTR_FSJW_MASK          0x3
 117
 118/* Test Register (TEST) */
 119#define TEST_LBCK       BIT(4)
 120
 121/* CC Control Register(CCCR) */
 122#define CCCR_TEST               BIT(7)
 123#define CCCR_CMR_MASK           0x3
 124#define CCCR_CMR_SHIFT          10
 125#define CCCR_CMR_CANFD          0x1
 126#define CCCR_CMR_CANFD_BRS      0x2
 127#define CCCR_CMR_CAN            0x3
 128#define CCCR_CME_MASK           0x3
 129#define CCCR_CME_SHIFT          8
 130#define CCCR_CME_CAN            0
 131#define CCCR_CME_CANFD          0x1
 132#define CCCR_CME_CANFD_BRS      0x2
 133#define CCCR_TEST               BIT(7)
 134#define CCCR_MON                BIT(5)
 135#define CCCR_CCE                BIT(1)
 136#define CCCR_INIT               BIT(0)
 137#define CCCR_CANFD              0x10
 138
 139/* Bit Timing & Prescaler Register (BTP) */
 140#define BTR_BRP_MASK            0x3ff
 141#define BTR_BRP_SHIFT           16
 142#define BTR_TSEG1_SHIFT         8
 143#define BTR_TSEG1_MASK          (0x3f << BTR_TSEG1_SHIFT)
 144#define BTR_TSEG2_SHIFT         4
 145#define BTR_TSEG2_MASK          (0xf << BTR_TSEG2_SHIFT)
 146#define BTR_SJW_SHIFT           0
 147#define BTR_SJW_MASK            0xf
 148
 149/* Error Counter Register(ECR) */
 150#define ECR_RP                  BIT(15)
 151#define ECR_REC_SHIFT           8
 152#define ECR_REC_MASK            (0x7f << ECR_REC_SHIFT)
 153#define ECR_TEC_SHIFT           0
 154#define ECR_TEC_MASK            0xff
 155
 156/* Protocol Status Register(PSR) */
 157#define PSR_BO          BIT(7)
 158#define PSR_EW          BIT(6)
 159#define PSR_EP          BIT(5)
 160#define PSR_LEC_MASK    0x7
 161
 162/* Interrupt Register(IR) */
 163#define IR_ALL_INT      0xffffffff
 164#define IR_STE          BIT(31)
 165#define IR_FOE          BIT(30)
 166#define IR_ACKE         BIT(29)
 167#define IR_BE           BIT(28)
 168#define IR_CRCE         BIT(27)
 169#define IR_WDI          BIT(26)
 170#define IR_BO           BIT(25)
 171#define IR_EW           BIT(24)
 172#define IR_EP           BIT(23)
 173#define IR_ELO          BIT(22)
 174#define IR_BEU          BIT(21)
 175#define IR_BEC          BIT(20)
 176#define IR_DRX          BIT(19)
 177#define IR_TOO          BIT(18)
 178#define IR_MRAF         BIT(17)
 179#define IR_TSW          BIT(16)
 180#define IR_TEFL         BIT(15)
 181#define IR_TEFF         BIT(14)
 182#define IR_TEFW         BIT(13)
 183#define IR_TEFN         BIT(12)
 184#define IR_TFE          BIT(11)
 185#define IR_TCF          BIT(10)
 186#define IR_TC           BIT(9)
 187#define IR_HPM          BIT(8)
 188#define IR_RF1L         BIT(7)
 189#define IR_RF1F         BIT(6)
 190#define IR_RF1W         BIT(5)
 191#define IR_RF1N         BIT(4)
 192#define IR_RF0L         BIT(3)
 193#define IR_RF0F         BIT(2)
 194#define IR_RF0W         BIT(1)
 195#define IR_RF0N         BIT(0)
 196#define IR_ERR_STATE    (IR_BO | IR_EW | IR_EP)
 197#define IR_ERR_LEC      (IR_STE | IR_FOE | IR_ACKE | IR_BE | IR_CRCE)
 198#define IR_ERR_BUS      (IR_ERR_LEC | IR_WDI | IR_ELO | IR_BEU | \
 199                         IR_BEC | IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | \
 200                         IR_RF1L | IR_RF0L)
 201#define IR_ERR_ALL      (IR_ERR_STATE | IR_ERR_BUS)
 202
 203/* Interrupt Line Select (ILS) */
 204#define ILS_ALL_INT0    0x0
 205#define ILS_ALL_INT1    0xFFFFFFFF
 206
 207/* Interrupt Line Enable (ILE) */
 208#define ILE_EINT0       BIT(0)
 209#define ILE_EINT1       BIT(1)
 210
 211/* Rx FIFO 0/1 Configuration (RXF0C/RXF1C) */
 212#define RXFC_FWM_OFF    24
 213#define RXFC_FWM_MASK   0x7f
 214#define RXFC_FWM_1      (1 << RXFC_FWM_OFF)
 215#define RXFC_FS_OFF     16
 216#define RXFC_FS_MASK    0x7f
 217
 218/* Rx FIFO 0/1 Status (RXF0S/RXF1S) */
 219#define RXFS_RFL        BIT(25)
 220#define RXFS_FF         BIT(24)
 221#define RXFS_FPI_OFF    16
 222#define RXFS_FPI_MASK   0x3f0000
 223#define RXFS_FGI_OFF    8
 224#define RXFS_FGI_MASK   0x3f00
 225#define RXFS_FFL_MASK   0x7f
 226
 227/* Rx Buffer / FIFO Element Size Configuration (RXESC) */
 228#define M_CAN_RXESC_8BYTES      0x0
 229#define M_CAN_RXESC_64BYTES     0x777
 230
 231/* Tx Buffer Configuration(TXBC) */
 232#define TXBC_NDTB_OFF           16
 233#define TXBC_NDTB_MASK          0x3f
 234
 235/* Tx Buffer Element Size Configuration(TXESC) */
 236#define TXESC_TBDS_8BYTES       0x0
 237#define TXESC_TBDS_64BYTES      0x7
 238
 239/* Tx Event FIFO Con.guration (TXEFC) */
 240#define TXEFC_EFS_OFF           16
 241#define TXEFC_EFS_MASK          0x3f
 242
 243/* Message RAM Configuration (in bytes) */
 244#define SIDF_ELEMENT_SIZE       4
 245#define XIDF_ELEMENT_SIZE       8
 246#define RXF0_ELEMENT_SIZE       72
 247#define RXF1_ELEMENT_SIZE       72
 248#define RXB_ELEMENT_SIZE        16
 249#define TXE_ELEMENT_SIZE        8
 250#define TXB_ELEMENT_SIZE        72
 251
 252/* Message RAM Elements */
 253#define M_CAN_FIFO_ID           0x0
 254#define M_CAN_FIFO_DLC          0x4
 255#define M_CAN_FIFO_DATA(n)      (0x8 + ((n) << 2))
 256
 257/* Rx Buffer Element */
 258/* R0 */
 259#define RX_BUF_ESI              BIT(31)
 260#define RX_BUF_XTD              BIT(30)
 261#define RX_BUF_RTR              BIT(29)
 262/* R1 */
 263#define RX_BUF_ANMF             BIT(31)
 264#define RX_BUF_EDL              BIT(21)
 265#define RX_BUF_BRS              BIT(20)
 266
 267/* Tx Buffer Element */
 268/* R0 */
 269#define TX_BUF_XTD              BIT(30)
 270#define TX_BUF_RTR              BIT(29)
 271
 272/* address offset and element number for each FIFO/Buffer in the Message RAM */
 273struct mram_cfg {
 274        u16 off;
 275        u8  num;
 276};
 277
 278/* m_can private data structure */
 279struct m_can_priv {
 280        struct can_priv can;    /* must be the first member */
 281        struct napi_struct napi;
 282        struct net_device *dev;
 283        struct device *device;
 284        struct clk *hclk;
 285        struct clk *cclk;
 286        void __iomem *base;
 287        u32 irqstatus;
 288
 289        /* message ram configuration */
 290        void __iomem *mram_base;
 291        struct mram_cfg mcfg[MRAM_CFG_NUM];
 292};
 293
 294static inline u32 m_can_read(const struct m_can_priv *priv, enum m_can_reg reg)
 295{
 296        return readl(priv->base + reg);
 297}
 298
 299static inline void m_can_write(const struct m_can_priv *priv,
 300                               enum m_can_reg reg, u32 val)
 301{
 302        writel(val, priv->base + reg);
 303}
 304
 305static inline u32 m_can_fifo_read(const struct m_can_priv *priv,
 306                                  u32 fgi, unsigned int offset)
 307{
 308        return readl(priv->mram_base + priv->mcfg[MRAM_RXF0].off +
 309                     fgi * RXF0_ELEMENT_SIZE + offset);
 310}
 311
 312static inline void m_can_fifo_write(const struct m_can_priv *priv,
 313                                    u32 fpi, unsigned int offset, u32 val)
 314{
 315        writel(val, priv->mram_base + priv->mcfg[MRAM_TXB].off +
 316               fpi * TXB_ELEMENT_SIZE + offset);
 317}
 318
 319static inline void m_can_config_endisable(const struct m_can_priv *priv,
 320                                          bool enable)
 321{
 322        u32 cccr = m_can_read(priv, M_CAN_CCCR);
 323        u32 timeout = 10;
 324        u32 val = 0;
 325
 326        if (enable) {
 327                /* enable m_can configuration */
 328                m_can_write(priv, M_CAN_CCCR, cccr | CCCR_INIT);
 329                udelay(5);
 330                /* CCCR.CCE can only be set/reset while CCCR.INIT = '1' */
 331                m_can_write(priv, M_CAN_CCCR, cccr | CCCR_INIT | CCCR_CCE);
 332        } else {
 333                m_can_write(priv, M_CAN_CCCR, cccr & ~(CCCR_INIT | CCCR_CCE));
 334        }
 335
 336        /* there's a delay for module initialization */
 337        if (enable)
 338                val = CCCR_INIT | CCCR_CCE;
 339
 340        while ((m_can_read(priv, M_CAN_CCCR) & (CCCR_INIT | CCCR_CCE)) != val) {
 341                if (timeout == 0) {
 342                        netdev_warn(priv->dev, "Failed to init module\n");
 343                        return;
 344                }
 345                timeout--;
 346                udelay(1);
 347        }
 348}
 349
 350static inline void m_can_enable_all_interrupts(const struct m_can_priv *priv)
 351{
 352        m_can_write(priv, M_CAN_ILE, ILE_EINT0 | ILE_EINT1);
 353}
 354
 355static inline void m_can_disable_all_interrupts(const struct m_can_priv *priv)
 356{
 357        m_can_write(priv, M_CAN_ILE, 0x0);
 358}
 359
 360static void m_can_read_fifo(struct net_device *dev, u32 rxfs)
 361{
 362        struct net_device_stats *stats = &dev->stats;
 363        struct m_can_priv *priv = netdev_priv(dev);
 364        struct canfd_frame *cf;
 365        struct sk_buff *skb;
 366        u32 id, fgi, dlc;
 367        int i;
 368
 369        /* calculate the fifo get index for where to read data */
 370        fgi = (rxfs & RXFS_FGI_MASK) >> RXFS_FGI_OFF;
 371        dlc = m_can_fifo_read(priv, fgi, M_CAN_FIFO_DLC);
 372        if (dlc & RX_BUF_EDL)
 373                skb = alloc_canfd_skb(dev, &cf);
 374        else
 375                skb = alloc_can_skb(dev, (struct can_frame **)&cf);
 376        if (!skb) {
 377                stats->rx_dropped++;
 378                return;
 379        }
 380
 381        if (dlc & RX_BUF_EDL)
 382                cf->len = can_dlc2len((dlc >> 16) & 0x0F);
 383        else
 384                cf->len = get_can_dlc((dlc >> 16) & 0x0F);
 385
 386        id = m_can_fifo_read(priv, fgi, M_CAN_FIFO_ID);
 387        if (id & RX_BUF_XTD)
 388                cf->can_id = (id & CAN_EFF_MASK) | CAN_EFF_FLAG;
 389        else
 390                cf->can_id = (id >> 18) & CAN_SFF_MASK;
 391
 392        if (id & RX_BUF_ESI) {
 393                cf->flags |= CANFD_ESI;
 394                netdev_dbg(dev, "ESI Error\n");
 395        }
 396
 397        if (!(dlc & RX_BUF_EDL) && (id & RX_BUF_RTR)) {
 398                cf->can_id |= CAN_RTR_FLAG;
 399        } else {
 400                if (dlc & RX_BUF_BRS)
 401                        cf->flags |= CANFD_BRS;
 402
 403                for (i = 0; i < cf->len; i += 4)
 404                        *(u32 *)(cf->data + i) =
 405                                m_can_fifo_read(priv, fgi,
 406                                                M_CAN_FIFO_DATA(i / 4));
 407        }
 408
 409        /* acknowledge rx fifo 0 */
 410        m_can_write(priv, M_CAN_RXF0A, fgi);
 411
 412        stats->rx_packets++;
 413        stats->rx_bytes += cf->len;
 414
 415        netif_receive_skb(skb);
 416}
 417
 418static int m_can_do_rx_poll(struct net_device *dev, int quota)
 419{
 420        struct m_can_priv *priv = netdev_priv(dev);
 421        u32 pkts = 0;
 422        u32 rxfs;
 423
 424        rxfs = m_can_read(priv, M_CAN_RXF0S);
 425        if (!(rxfs & RXFS_FFL_MASK)) {
 426                netdev_dbg(dev, "no messages in fifo0\n");
 427                return 0;
 428        }
 429
 430        while ((rxfs & RXFS_FFL_MASK) && (quota > 0)) {
 431                if (rxfs & RXFS_RFL)
 432                        netdev_warn(dev, "Rx FIFO 0 Message Lost\n");
 433
 434                m_can_read_fifo(dev, rxfs);
 435
 436                quota--;
 437                pkts++;
 438                rxfs = m_can_read(priv, M_CAN_RXF0S);
 439        }
 440
 441        if (pkts)
 442                can_led_event(dev, CAN_LED_EVENT_RX);
 443
 444        return pkts;
 445}
 446
 447static int m_can_handle_lost_msg(struct net_device *dev)
 448{
 449        struct net_device_stats *stats = &dev->stats;
 450        struct sk_buff *skb;
 451        struct can_frame *frame;
 452
 453        netdev_err(dev, "msg lost in rxf0\n");
 454
 455        stats->rx_errors++;
 456        stats->rx_over_errors++;
 457
 458        skb = alloc_can_err_skb(dev, &frame);
 459        if (unlikely(!skb))
 460                return 0;
 461
 462        frame->can_id |= CAN_ERR_CRTL;
 463        frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 464
 465        netif_receive_skb(skb);
 466
 467        return 1;
 468}
 469
 470static int m_can_handle_lec_err(struct net_device *dev,
 471                                enum m_can_lec_type lec_type)
 472{
 473        struct m_can_priv *priv = netdev_priv(dev);
 474        struct net_device_stats *stats = &dev->stats;
 475        struct can_frame *cf;
 476        struct sk_buff *skb;
 477
 478        priv->can.can_stats.bus_error++;
 479        stats->rx_errors++;
 480
 481        /* propagate the error condition to the CAN stack */
 482        skb = alloc_can_err_skb(dev, &cf);
 483        if (unlikely(!skb))
 484                return 0;
 485
 486        /* check for 'last error code' which tells us the
 487         * type of the last error to occur on the CAN bus
 488         */
 489        cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 490
 491        switch (lec_type) {
 492        case LEC_STUFF_ERROR:
 493                netdev_dbg(dev, "stuff error\n");
 494                cf->data[2] |= CAN_ERR_PROT_STUFF;
 495                break;
 496        case LEC_FORM_ERROR:
 497                netdev_dbg(dev, "form error\n");
 498                cf->data[2] |= CAN_ERR_PROT_FORM;
 499                break;
 500        case LEC_ACK_ERROR:
 501                netdev_dbg(dev, "ack error\n");
 502                cf->data[3] = CAN_ERR_PROT_LOC_ACK;
 503                break;
 504        case LEC_BIT1_ERROR:
 505                netdev_dbg(dev, "bit1 error\n");
 506                cf->data[2] |= CAN_ERR_PROT_BIT1;
 507                break;
 508        case LEC_BIT0_ERROR:
 509                netdev_dbg(dev, "bit0 error\n");
 510                cf->data[2] |= CAN_ERR_PROT_BIT0;
 511                break;
 512        case LEC_CRC_ERROR:
 513                netdev_dbg(dev, "CRC error\n");
 514                cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
 515                break;
 516        default:
 517                break;
 518        }
 519
 520        stats->rx_packets++;
 521        stats->rx_bytes += cf->can_dlc;
 522        netif_receive_skb(skb);
 523
 524        return 1;
 525}
 526
 527static int __m_can_get_berr_counter(const struct net_device *dev,
 528                                    struct can_berr_counter *bec)
 529{
 530        struct m_can_priv *priv = netdev_priv(dev);
 531        unsigned int ecr;
 532
 533        ecr = m_can_read(priv, M_CAN_ECR);
 534        bec->rxerr = (ecr & ECR_REC_MASK) >> ECR_REC_SHIFT;
 535        bec->txerr = ecr & ECR_TEC_MASK;
 536
 537        return 0;
 538}
 539
 540static int m_can_get_berr_counter(const struct net_device *dev,
 541                                  struct can_berr_counter *bec)
 542{
 543        struct m_can_priv *priv = netdev_priv(dev);
 544        int err;
 545
 546        err = clk_prepare_enable(priv->hclk);
 547        if (err)
 548                return err;
 549
 550        err = clk_prepare_enable(priv->cclk);
 551        if (err) {
 552                clk_disable_unprepare(priv->hclk);
 553                return err;
 554        }
 555
 556        __m_can_get_berr_counter(dev, bec);
 557
 558        clk_disable_unprepare(priv->cclk);
 559        clk_disable_unprepare(priv->hclk);
 560
 561        return 0;
 562}
 563
 564static int m_can_handle_state_change(struct net_device *dev,
 565                                     enum can_state new_state)
 566{
 567        struct m_can_priv *priv = netdev_priv(dev);
 568        struct net_device_stats *stats = &dev->stats;
 569        struct can_frame *cf;
 570        struct sk_buff *skb;
 571        struct can_berr_counter bec;
 572        unsigned int ecr;
 573
 574        switch (new_state) {
 575        case CAN_STATE_ERROR_ACTIVE:
 576                /* error warning state */
 577                priv->can.can_stats.error_warning++;
 578                priv->can.state = CAN_STATE_ERROR_WARNING;
 579                break;
 580        case CAN_STATE_ERROR_PASSIVE:
 581                /* error passive state */
 582                priv->can.can_stats.error_passive++;
 583                priv->can.state = CAN_STATE_ERROR_PASSIVE;
 584                break;
 585        case CAN_STATE_BUS_OFF:
 586                /* bus-off state */
 587                priv->can.state = CAN_STATE_BUS_OFF;
 588                m_can_disable_all_interrupts(priv);
 589                priv->can.can_stats.bus_off++;
 590                can_bus_off(dev);
 591                break;
 592        default:
 593                break;
 594        }
 595
 596        /* propagate the error condition to the CAN stack */
 597        skb = alloc_can_err_skb(dev, &cf);
 598        if (unlikely(!skb))
 599                return 0;
 600
 601        __m_can_get_berr_counter(dev, &bec);
 602
 603        switch (new_state) {
 604        case CAN_STATE_ERROR_ACTIVE:
 605                /* error warning state */
 606                cf->can_id |= CAN_ERR_CRTL;
 607                cf->data[1] = (bec.txerr > bec.rxerr) ?
 608                        CAN_ERR_CRTL_TX_WARNING :
 609                        CAN_ERR_CRTL_RX_WARNING;
 610                cf->data[6] = bec.txerr;
 611                cf->data[7] = bec.rxerr;
 612                break;
 613        case CAN_STATE_ERROR_PASSIVE:
 614                /* error passive state */
 615                cf->can_id |= CAN_ERR_CRTL;
 616                ecr = m_can_read(priv, M_CAN_ECR);
 617                if (ecr & ECR_RP)
 618                        cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
 619                if (bec.txerr > 127)
 620                        cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
 621                cf->data[6] = bec.txerr;
 622                cf->data[7] = bec.rxerr;
 623                break;
 624        case CAN_STATE_BUS_OFF:
 625                /* bus-off state */
 626                cf->can_id |= CAN_ERR_BUSOFF;
 627                break;
 628        default:
 629                break;
 630        }
 631
 632        stats->rx_packets++;
 633        stats->rx_bytes += cf->can_dlc;
 634        netif_receive_skb(skb);
 635
 636        return 1;
 637}
 638
 639static int m_can_handle_state_errors(struct net_device *dev, u32 psr)
 640{
 641        struct m_can_priv *priv = netdev_priv(dev);
 642        int work_done = 0;
 643
 644        if ((psr & PSR_EW) &&
 645            (priv->can.state != CAN_STATE_ERROR_WARNING)) {
 646                netdev_dbg(dev, "entered error warning state\n");
 647                work_done += m_can_handle_state_change(dev,
 648                                                       CAN_STATE_ERROR_WARNING);
 649        }
 650
 651        if ((psr & PSR_EP) &&
 652            (priv->can.state != CAN_STATE_ERROR_PASSIVE)) {
 653                netdev_dbg(dev, "entered error passive state\n");
 654                work_done += m_can_handle_state_change(dev,
 655                                                       CAN_STATE_ERROR_PASSIVE);
 656        }
 657
 658        if ((psr & PSR_BO) &&
 659            (priv->can.state != CAN_STATE_BUS_OFF)) {
 660                netdev_dbg(dev, "entered error bus off state\n");
 661                work_done += m_can_handle_state_change(dev,
 662                                                       CAN_STATE_BUS_OFF);
 663        }
 664
 665        return work_done;
 666}
 667
 668static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus)
 669{
 670        if (irqstatus & IR_WDI)
 671                netdev_err(dev, "Message RAM Watchdog event due to missing READY\n");
 672        if (irqstatus & IR_ELO)
 673                netdev_err(dev, "Error Logging Overflow\n");
 674        if (irqstatus & IR_BEU)
 675                netdev_err(dev, "Bit Error Uncorrected\n");
 676        if (irqstatus & IR_BEC)
 677                netdev_err(dev, "Bit Error Corrected\n");
 678        if (irqstatus & IR_TOO)
 679                netdev_err(dev, "Timeout reached\n");
 680        if (irqstatus & IR_MRAF)
 681                netdev_err(dev, "Message RAM access failure occurred\n");
 682}
 683
 684static inline bool is_lec_err(u32 psr)
 685{
 686        psr &= LEC_UNUSED;
 687
 688        return psr && (psr != LEC_UNUSED);
 689}
 690
 691static int m_can_handle_bus_errors(struct net_device *dev, u32 irqstatus,
 692                                   u32 psr)
 693{
 694        struct m_can_priv *priv = netdev_priv(dev);
 695        int work_done = 0;
 696
 697        if (irqstatus & IR_RF0L)
 698                work_done += m_can_handle_lost_msg(dev);
 699
 700        /* handle lec errors on the bus */
 701        if ((priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
 702            is_lec_err(psr))
 703                work_done += m_can_handle_lec_err(dev, psr & LEC_UNUSED);
 704
 705        /* other unproccessed error interrupts */
 706        m_can_handle_other_err(dev, irqstatus);
 707
 708        return work_done;
 709}
 710
 711static int m_can_poll(struct napi_struct *napi, int quota)
 712{
 713        struct net_device *dev = napi->dev;
 714        struct m_can_priv *priv = netdev_priv(dev);
 715        int work_done = 0;
 716        u32 irqstatus, psr;
 717
 718        irqstatus = priv->irqstatus | m_can_read(priv, M_CAN_IR);
 719        if (!irqstatus)
 720                goto end;
 721
 722        psr = m_can_read(priv, M_CAN_PSR);
 723        if (irqstatus & IR_ERR_STATE)
 724                work_done += m_can_handle_state_errors(dev, psr);
 725
 726        if (irqstatus & IR_ERR_BUS)
 727                work_done += m_can_handle_bus_errors(dev, irqstatus, psr);
 728
 729        if (irqstatus & IR_RF0N)
 730                work_done += m_can_do_rx_poll(dev, (quota - work_done));
 731
 732        if (work_done < quota) {
 733                napi_complete(napi);
 734                m_can_enable_all_interrupts(priv);
 735        }
 736
 737end:
 738        return work_done;
 739}
 740
 741static irqreturn_t m_can_isr(int irq, void *dev_id)
 742{
 743        struct net_device *dev = (struct net_device *)dev_id;
 744        struct m_can_priv *priv = netdev_priv(dev);
 745        struct net_device_stats *stats = &dev->stats;
 746        u32 ir;
 747
 748        ir = m_can_read(priv, M_CAN_IR);
 749        if (!ir)
 750                return IRQ_NONE;
 751
 752        /* ACK all irqs */
 753        if (ir & IR_ALL_INT)
 754                m_can_write(priv, M_CAN_IR, ir);
 755
 756        /* schedule NAPI in case of
 757         * - rx IRQ
 758         * - state change IRQ
 759         * - bus error IRQ and bus error reporting
 760         */
 761        if ((ir & IR_RF0N) || (ir & IR_ERR_ALL)) {
 762                priv->irqstatus = ir;
 763                m_can_disable_all_interrupts(priv);
 764                napi_schedule(&priv->napi);
 765        }
 766
 767        /* transmission complete interrupt */
 768        if (ir & IR_TC) {
 769                stats->tx_bytes += can_get_echo_skb(dev, 0);
 770                stats->tx_packets++;
 771                can_led_event(dev, CAN_LED_EVENT_TX);
 772                netif_wake_queue(dev);
 773        }
 774
 775        return IRQ_HANDLED;
 776}
 777
 778static const struct can_bittiming_const m_can_bittiming_const = {
 779        .name = KBUILD_MODNAME,
 780        .tseg1_min = 2,         /* Time segment 1 = prop_seg + phase_seg1 */
 781        .tseg1_max = 64,
 782        .tseg2_min = 1,         /* Time segment 2 = phase_seg2 */
 783        .tseg2_max = 16,
 784        .sjw_max = 16,
 785        .brp_min = 1,
 786        .brp_max = 1024,
 787        .brp_inc = 1,
 788};
 789
 790static const struct can_bittiming_const m_can_data_bittiming_const = {
 791        .name = KBUILD_MODNAME,
 792        .tseg1_min = 2,         /* Time segment 1 = prop_seg + phase_seg1 */
 793        .tseg1_max = 16,
 794        .tseg2_min = 1,         /* Time segment 2 = phase_seg2 */
 795        .tseg2_max = 8,
 796        .sjw_max = 4,
 797        .brp_min = 1,
 798        .brp_max = 32,
 799        .brp_inc = 1,
 800};
 801
 802static int m_can_set_bittiming(struct net_device *dev)
 803{
 804        struct m_can_priv *priv = netdev_priv(dev);
 805        const struct can_bittiming *bt = &priv->can.bittiming;
 806        const struct can_bittiming *dbt = &priv->can.data_bittiming;
 807        u16 brp, sjw, tseg1, tseg2;
 808        u32 reg_btp;
 809
 810        brp = bt->brp - 1;
 811        sjw = bt->sjw - 1;
 812        tseg1 = bt->prop_seg + bt->phase_seg1 - 1;
 813        tseg2 = bt->phase_seg2 - 1;
 814        reg_btp = (brp << BTR_BRP_SHIFT) | (sjw << BTR_SJW_SHIFT) |
 815                        (tseg1 << BTR_TSEG1_SHIFT) | (tseg2 << BTR_TSEG2_SHIFT);
 816        m_can_write(priv, M_CAN_BTP, reg_btp);
 817
 818        if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
 819                brp = dbt->brp - 1;
 820                sjw = dbt->sjw - 1;
 821                tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1;
 822                tseg2 = dbt->phase_seg2 - 1;
 823                reg_btp = (brp << FBTR_FBRP_SHIFT) | (sjw << FBTR_FSJW_SHIFT) |
 824                                (tseg1 << FBTR_FTSEG1_SHIFT) |
 825                                (tseg2 << FBTR_FTSEG2_SHIFT);
 826                m_can_write(priv, M_CAN_FBTP, reg_btp);
 827        }
 828
 829        return 0;
 830}
 831
 832/* Configure M_CAN chip:
 833 * - set rx buffer/fifo element size
 834 * - configure rx fifo
 835 * - accept non-matching frame into fifo 0
 836 * - configure tx buffer
 837 * - configure mode
 838 * - setup bittiming
 839 */
 840static void m_can_chip_config(struct net_device *dev)
 841{
 842        struct m_can_priv *priv = netdev_priv(dev);
 843        u32 cccr, test;
 844
 845        m_can_config_endisable(priv, true);
 846
 847        /* RX Buffer/FIFO Element Size 64 bytes data field */
 848        m_can_write(priv, M_CAN_RXESC, M_CAN_RXESC_64BYTES);
 849
 850        /* Accept Non-matching Frames Into FIFO 0 */
 851        m_can_write(priv, M_CAN_GFC, 0x0);
 852
 853        /* only support one Tx Buffer currently */
 854        m_can_write(priv, M_CAN_TXBC, (1 << TXBC_NDTB_OFF) |
 855                    priv->mcfg[MRAM_TXB].off);
 856
 857        /* support 64 bytes payload */
 858        m_can_write(priv, M_CAN_TXESC, TXESC_TBDS_64BYTES);
 859
 860        m_can_write(priv, M_CAN_TXEFC, (1 << TXEFC_EFS_OFF) |
 861                    priv->mcfg[MRAM_TXE].off);
 862
 863        /* rx fifo configuration, blocking mode, fifo size 1 */
 864        m_can_write(priv, M_CAN_RXF0C,
 865                    (priv->mcfg[MRAM_RXF0].num << RXFC_FS_OFF) |
 866                    RXFC_FWM_1 | priv->mcfg[MRAM_RXF0].off);
 867
 868        m_can_write(priv, M_CAN_RXF1C,
 869                    (priv->mcfg[MRAM_RXF1].num << RXFC_FS_OFF) |
 870                    RXFC_FWM_1 | priv->mcfg[MRAM_RXF1].off);
 871
 872        cccr = m_can_read(priv, M_CAN_CCCR);
 873        cccr &= ~(CCCR_TEST | CCCR_MON | (CCCR_CMR_MASK << CCCR_CMR_SHIFT) |
 874                (CCCR_CME_MASK << CCCR_CME_SHIFT));
 875        test = m_can_read(priv, M_CAN_TEST);
 876        test &= ~TEST_LBCK;
 877
 878        if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 879                cccr |= CCCR_MON;
 880
 881        if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
 882                cccr |= CCCR_TEST;
 883                test |= TEST_LBCK;
 884        }
 885
 886        if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
 887                cccr |= CCCR_CME_CANFD_BRS << CCCR_CME_SHIFT;
 888
 889        m_can_write(priv, M_CAN_CCCR, cccr);
 890        m_can_write(priv, M_CAN_TEST, test);
 891
 892        /* enable interrupts */
 893        m_can_write(priv, M_CAN_IR, IR_ALL_INT);
 894        if (!(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
 895                m_can_write(priv, M_CAN_IE, IR_ALL_INT & ~IR_ERR_LEC);
 896        else
 897                m_can_write(priv, M_CAN_IE, IR_ALL_INT);
 898
 899        /* route all interrupts to INT0 */
 900        m_can_write(priv, M_CAN_ILS, ILS_ALL_INT0);
 901
 902        /* set bittiming params */
 903        m_can_set_bittiming(dev);
 904
 905        m_can_config_endisable(priv, false);
 906}
 907
 908static void m_can_start(struct net_device *dev)
 909{
 910        struct m_can_priv *priv = netdev_priv(dev);
 911
 912        /* basic m_can configuration */
 913        m_can_chip_config(dev);
 914
 915        priv->can.state = CAN_STATE_ERROR_ACTIVE;
 916
 917        m_can_enable_all_interrupts(priv);
 918}
 919
 920static int m_can_set_mode(struct net_device *dev, enum can_mode mode)
 921{
 922        switch (mode) {
 923        case CAN_MODE_START:
 924                m_can_start(dev);
 925                netif_wake_queue(dev);
 926                break;
 927        default:
 928                return -EOPNOTSUPP;
 929        }
 930
 931        return 0;
 932}
 933
 934static void free_m_can_dev(struct net_device *dev)
 935{
 936        free_candev(dev);
 937}
 938
 939static struct net_device *alloc_m_can_dev(void)
 940{
 941        struct net_device *dev;
 942        struct m_can_priv *priv;
 943
 944        dev = alloc_candev(sizeof(*priv), 1);
 945        if (!dev)
 946                return NULL;
 947
 948        priv = netdev_priv(dev);
 949        netif_napi_add(dev, &priv->napi, m_can_poll, M_CAN_NAPI_WEIGHT);
 950
 951        priv->dev = dev;
 952        priv->can.bittiming_const = &m_can_bittiming_const;
 953        priv->can.data_bittiming_const = &m_can_data_bittiming_const;
 954        priv->can.do_set_mode = m_can_set_mode;
 955        priv->can.do_get_berr_counter = m_can_get_berr_counter;
 956
 957        /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.0.1 */
 958        can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO);
 959
 960        /* CAN_CTRLMODE_FD_NON_ISO can not be changed with M_CAN IP v3.0.1 */
 961        priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
 962                                        CAN_CTRLMODE_LISTENONLY |
 963                                        CAN_CTRLMODE_BERR_REPORTING |
 964                                        CAN_CTRLMODE_FD;
 965
 966        return dev;
 967}
 968
 969static int m_can_open(struct net_device *dev)
 970{
 971        struct m_can_priv *priv = netdev_priv(dev);
 972        int err;
 973
 974        err = clk_prepare_enable(priv->hclk);
 975        if (err)
 976                return err;
 977
 978        err = clk_prepare_enable(priv->cclk);
 979        if (err)
 980                goto exit_disable_hclk;
 981
 982        /* open the can device */
 983        err = open_candev(dev);
 984        if (err) {
 985                netdev_err(dev, "failed to open can device\n");
 986                goto exit_disable_cclk;
 987        }
 988
 989        /* register interrupt handler */
 990        err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
 991                          dev);
 992        if (err < 0) {
 993                netdev_err(dev, "failed to request interrupt\n");
 994                goto exit_irq_fail;
 995        }
 996
 997        /* start the m_can controller */
 998        m_can_start(dev);
 999
1000        can_led_event(dev, CAN_LED_EVENT_OPEN);
1001        napi_enable(&priv->napi);
1002        netif_start_queue(dev);
1003
1004        return 0;
1005
1006exit_irq_fail:
1007        close_candev(dev);
1008exit_disable_cclk:
1009        clk_disable_unprepare(priv->cclk);
1010exit_disable_hclk:
1011        clk_disable_unprepare(priv->hclk);
1012        return err;
1013}
1014
1015static void m_can_stop(struct net_device *dev)
1016{
1017        struct m_can_priv *priv = netdev_priv(dev);
1018
1019        /* disable all interrupts */
1020        m_can_disable_all_interrupts(priv);
1021
1022        clk_disable_unprepare(priv->hclk);
1023        clk_disable_unprepare(priv->cclk);
1024
1025        /* set the state as STOPPED */
1026        priv->can.state = CAN_STATE_STOPPED;
1027}
1028
1029static int m_can_close(struct net_device *dev)
1030{
1031        struct m_can_priv *priv = netdev_priv(dev);
1032
1033        netif_stop_queue(dev);
1034        napi_disable(&priv->napi);
1035        m_can_stop(dev);
1036        free_irq(dev->irq, dev);
1037        close_candev(dev);
1038        can_led_event(dev, CAN_LED_EVENT_STOP);
1039
1040        return 0;
1041}
1042
1043static netdev_tx_t m_can_start_xmit(struct sk_buff *skb,
1044                                    struct net_device *dev)
1045{
1046        struct m_can_priv *priv = netdev_priv(dev);
1047        struct canfd_frame *cf = (struct canfd_frame *)skb->data;
1048        u32 id, cccr;
1049        int i;
1050
1051        if (can_dropped_invalid_skb(dev, skb))
1052                return NETDEV_TX_OK;
1053
1054        netif_stop_queue(dev);
1055
1056        if (cf->can_id & CAN_EFF_FLAG) {
1057                id = cf->can_id & CAN_EFF_MASK;
1058                id |= TX_BUF_XTD;
1059        } else {
1060                id = ((cf->can_id & CAN_SFF_MASK) << 18);
1061        }
1062
1063        if (cf->can_id & CAN_RTR_FLAG)
1064                id |= TX_BUF_RTR;
1065
1066        /* message ram configuration */
1067        m_can_fifo_write(priv, 0, M_CAN_FIFO_ID, id);
1068        m_can_fifo_write(priv, 0, M_CAN_FIFO_DLC, can_len2dlc(cf->len) << 16);
1069
1070        for (i = 0; i < cf->len; i += 4)
1071                m_can_fifo_write(priv, 0, M_CAN_FIFO_DATA(i / 4),
1072                                 *(u32 *)(cf->data + i));
1073
1074        can_put_echo_skb(skb, dev, 0);
1075
1076        if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1077                cccr = m_can_read(priv, M_CAN_CCCR);
1078                cccr &= ~(CCCR_CMR_MASK << CCCR_CMR_SHIFT);
1079                if (can_is_canfd_skb(skb)) {
1080                        if (cf->flags & CANFD_BRS)
1081                                cccr |= CCCR_CMR_CANFD_BRS << CCCR_CMR_SHIFT;
1082                        else
1083                                cccr |= CCCR_CMR_CANFD << CCCR_CMR_SHIFT;
1084                } else {
1085                        cccr |= CCCR_CMR_CAN << CCCR_CMR_SHIFT;
1086                }
1087                m_can_write(priv, M_CAN_CCCR, cccr);
1088        }
1089
1090        /* enable first TX buffer to start transfer  */
1091        m_can_write(priv, M_CAN_TXBTIE, 0x1);
1092        m_can_write(priv, M_CAN_TXBAR, 0x1);
1093
1094        return NETDEV_TX_OK;
1095}
1096
1097static const struct net_device_ops m_can_netdev_ops = {
1098        .ndo_open = m_can_open,
1099        .ndo_stop = m_can_close,
1100        .ndo_start_xmit = m_can_start_xmit,
1101        .ndo_change_mtu = can_change_mtu,
1102};
1103
1104static int register_m_can_dev(struct net_device *dev)
1105{
1106        dev->flags |= IFF_ECHO; /* we support local echo */
1107        dev->netdev_ops = &m_can_netdev_ops;
1108
1109        return register_candev(dev);
1110}
1111
1112static int m_can_of_parse_mram(struct platform_device *pdev,
1113                               struct m_can_priv *priv)
1114{
1115        struct device_node *np = pdev->dev.of_node;
1116        struct resource *res;
1117        void __iomem *addr;
1118        u32 out_val[MRAM_CFG_LEN];
1119        int i, start, end, ret;
1120
1121        /* message ram could be shared */
1122        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "message_ram");
1123        if (!res)
1124                return -ENODEV;
1125
1126        addr = devm_ioremap(&pdev->dev, res->start, resource_size(res));
1127        if (!addr)
1128                return -ENOMEM;
1129
1130        /* get message ram configuration */
1131        ret = of_property_read_u32_array(np, "bosch,mram-cfg",
1132                                         out_val, sizeof(out_val) / 4);
1133        if (ret) {
1134                dev_err(&pdev->dev, "can not get message ram configuration\n");
1135                return -ENODEV;
1136        }
1137
1138        priv->mram_base = addr;
1139        priv->mcfg[MRAM_SIDF].off = out_val[0];
1140        priv->mcfg[MRAM_SIDF].num = out_val[1];
1141        priv->mcfg[MRAM_XIDF].off = priv->mcfg[MRAM_SIDF].off +
1142                        priv->mcfg[MRAM_SIDF].num * SIDF_ELEMENT_SIZE;
1143        priv->mcfg[MRAM_XIDF].num = out_val[2];
1144        priv->mcfg[MRAM_RXF0].off = priv->mcfg[MRAM_XIDF].off +
1145                        priv->mcfg[MRAM_XIDF].num * XIDF_ELEMENT_SIZE;
1146        priv->mcfg[MRAM_RXF0].num = out_val[3] & RXFC_FS_MASK;
1147        priv->mcfg[MRAM_RXF1].off = priv->mcfg[MRAM_RXF0].off +
1148                        priv->mcfg[MRAM_RXF0].num * RXF0_ELEMENT_SIZE;
1149        priv->mcfg[MRAM_RXF1].num = out_val[4] & RXFC_FS_MASK;
1150        priv->mcfg[MRAM_RXB].off = priv->mcfg[MRAM_RXF1].off +
1151                        priv->mcfg[MRAM_RXF1].num * RXF1_ELEMENT_SIZE;
1152        priv->mcfg[MRAM_RXB].num = out_val[5];
1153        priv->mcfg[MRAM_TXE].off = priv->mcfg[MRAM_RXB].off +
1154                        priv->mcfg[MRAM_RXB].num * RXB_ELEMENT_SIZE;
1155        priv->mcfg[MRAM_TXE].num = out_val[6];
1156        priv->mcfg[MRAM_TXB].off = priv->mcfg[MRAM_TXE].off +
1157                        priv->mcfg[MRAM_TXE].num * TXE_ELEMENT_SIZE;
1158        priv->mcfg[MRAM_TXB].num = out_val[7] & TXBC_NDTB_MASK;
1159
1160        dev_dbg(&pdev->dev, "mram_base %p sidf 0x%x %d xidf 0x%x %d rxf0 0x%x %d rxf1 0x%x %d rxb 0x%x %d txe 0x%x %d txb 0x%x %d\n",
1161                priv->mram_base,
1162                priv->mcfg[MRAM_SIDF].off, priv->mcfg[MRAM_SIDF].num,
1163                priv->mcfg[MRAM_XIDF].off, priv->mcfg[MRAM_XIDF].num,
1164                priv->mcfg[MRAM_RXF0].off, priv->mcfg[MRAM_RXF0].num,
1165                priv->mcfg[MRAM_RXF1].off, priv->mcfg[MRAM_RXF1].num,
1166                priv->mcfg[MRAM_RXB].off, priv->mcfg[MRAM_RXB].num,
1167                priv->mcfg[MRAM_TXE].off, priv->mcfg[MRAM_TXE].num,
1168                priv->mcfg[MRAM_TXB].off, priv->mcfg[MRAM_TXB].num);
1169
1170        /* initialize the entire Message RAM in use to avoid possible
1171         * ECC/parity checksum errors when reading an uninitialized buffer
1172         */
1173        start = priv->mcfg[MRAM_SIDF].off;
1174        end = priv->mcfg[MRAM_TXB].off +
1175                priv->mcfg[MRAM_TXB].num * TXB_ELEMENT_SIZE;
1176        for (i = start; i < end; i += 4)
1177                writel(0x0, priv->mram_base + i);
1178
1179        return 0;
1180}
1181
1182static int m_can_plat_probe(struct platform_device *pdev)
1183{
1184        struct net_device *dev;
1185        struct m_can_priv *priv;
1186        struct resource *res;
1187        void __iomem *addr;
1188        struct clk *hclk, *cclk;
1189        int irq, ret;
1190
1191        hclk = devm_clk_get(&pdev->dev, "hclk");
1192        cclk = devm_clk_get(&pdev->dev, "cclk");
1193        if (IS_ERR(hclk) || IS_ERR(cclk)) {
1194                dev_err(&pdev->dev, "no clock find\n");
1195                return -ENODEV;
1196        }
1197
1198        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "m_can");
1199        addr = devm_ioremap_resource(&pdev->dev, res);
1200        irq = platform_get_irq_byname(pdev, "int0");
1201        if (IS_ERR(addr) || irq < 0)
1202                return -EINVAL;
1203
1204        /* allocate the m_can device */
1205        dev = alloc_m_can_dev();
1206        if (!dev)
1207                return -ENOMEM;
1208
1209        priv = netdev_priv(dev);
1210        dev->irq = irq;
1211        priv->base = addr;
1212        priv->device = &pdev->dev;
1213        priv->hclk = hclk;
1214        priv->cclk = cclk;
1215        priv->can.clock.freq = clk_get_rate(cclk);
1216
1217        ret = m_can_of_parse_mram(pdev, priv);
1218        if (ret)
1219                goto failed_free_dev;
1220
1221        platform_set_drvdata(pdev, dev);
1222        SET_NETDEV_DEV(dev, &pdev->dev);
1223
1224        ret = register_m_can_dev(dev);
1225        if (ret) {
1226                dev_err(&pdev->dev, "registering %s failed (err=%d)\n",
1227                        KBUILD_MODNAME, ret);
1228                goto failed_free_dev;
1229        }
1230
1231        devm_can_led_init(dev);
1232
1233        dev_info(&pdev->dev, "%s device registered (regs=%p, irq=%d)\n",
1234                 KBUILD_MODNAME, priv->base, dev->irq);
1235
1236        return 0;
1237
1238failed_free_dev:
1239        free_m_can_dev(dev);
1240        return ret;
1241}
1242
1243static __maybe_unused int m_can_suspend(struct device *dev)
1244{
1245        struct net_device *ndev = dev_get_drvdata(dev);
1246        struct m_can_priv *priv = netdev_priv(ndev);
1247
1248        if (netif_running(ndev)) {
1249                netif_stop_queue(ndev);
1250                netif_device_detach(ndev);
1251        }
1252
1253        /* TODO: enter low power */
1254
1255        priv->can.state = CAN_STATE_SLEEPING;
1256
1257        return 0;
1258}
1259
1260static __maybe_unused int m_can_resume(struct device *dev)
1261{
1262        struct net_device *ndev = dev_get_drvdata(dev);
1263        struct m_can_priv *priv = netdev_priv(ndev);
1264
1265        /* TODO: exit low power */
1266
1267        priv->can.state = CAN_STATE_ERROR_ACTIVE;
1268
1269        if (netif_running(ndev)) {
1270                netif_device_attach(ndev);
1271                netif_start_queue(ndev);
1272        }
1273
1274        return 0;
1275}
1276
1277static void unregister_m_can_dev(struct net_device *dev)
1278{
1279        unregister_candev(dev);
1280}
1281
1282static int m_can_plat_remove(struct platform_device *pdev)
1283{
1284        struct net_device *dev = platform_get_drvdata(pdev);
1285
1286        unregister_m_can_dev(dev);
1287        platform_set_drvdata(pdev, NULL);
1288
1289        free_m_can_dev(dev);
1290
1291        return 0;
1292}
1293
1294static const struct dev_pm_ops m_can_pmops = {
1295        SET_SYSTEM_SLEEP_PM_OPS(m_can_suspend, m_can_resume)
1296};
1297
1298static const struct of_device_id m_can_of_table[] = {
1299        { .compatible = "bosch,m_can", .data = NULL },
1300        { /* sentinel */ },
1301};
1302MODULE_DEVICE_TABLE(of, m_can_of_table);
1303
1304static struct platform_driver m_can_plat_driver = {
1305        .driver = {
1306                .name = KBUILD_MODNAME,
1307                .of_match_table = m_can_of_table,
1308                .pm     = &m_can_pmops,
1309        },
1310        .probe = m_can_plat_probe,
1311        .remove = m_can_plat_remove,
1312};
1313
1314module_platform_driver(m_can_plat_driver);
1315
1316MODULE_AUTHOR("Dong Aisheng <b29396@freescale.com>");
1317MODULE_LICENSE("GPL v2");
1318MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller");
1319