linux/drivers/i2c/busses/i2c-imx-lpi2c.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * This is i.MX low power i2c controller driver.
   4 *
   5 * Copyright 2016 Freescale Semiconductor, Inc.
   6 */
   7
   8#include <linux/clk.h>
   9#include <linux/completion.h>
  10#include <linux/delay.h>
  11#include <linux/err.h>
  12#include <linux/errno.h>
  13#include <linux/i2c.h>
  14#include <linux/init.h>
  15#include <linux/interrupt.h>
  16#include <linux/io.h>
  17#include <linux/kernel.h>
  18#include <linux/module.h>
  19#include <linux/of.h>
  20#include <linux/of_device.h>
  21#include <linux/pinctrl/consumer.h>
  22#include <linux/platform_device.h>
  23#include <linux/pm_runtime.h>
  24#include <linux/sched.h>
  25#include <linux/slab.h>
  26
  27#define DRIVER_NAME "imx-lpi2c"
  28
  29#define LPI2C_PARAM     0x04    /* i2c RX/TX FIFO size */
  30#define LPI2C_MCR       0x10    /* i2c contrl register */
  31#define LPI2C_MSR       0x14    /* i2c status register */
  32#define LPI2C_MIER      0x18    /* i2c interrupt enable */
  33#define LPI2C_MCFGR0    0x20    /* i2c master configuration */
  34#define LPI2C_MCFGR1    0x24    /* i2c master configuration */
  35#define LPI2C_MCFGR2    0x28    /* i2c master configuration */
  36#define LPI2C_MCFGR3    0x2C    /* i2c master configuration */
  37#define LPI2C_MCCR0     0x48    /* i2c master clk configuration */
  38#define LPI2C_MCCR1     0x50    /* i2c master clk configuration */
  39#define LPI2C_MFCR      0x58    /* i2c master FIFO control */
  40#define LPI2C_MFSR      0x5C    /* i2c master FIFO status */
  41#define LPI2C_MTDR      0x60    /* i2c master TX data register */
  42#define LPI2C_MRDR      0x70    /* i2c master RX data register */
  43
  44/* i2c command */
  45#define TRAN_DATA       0X00
  46#define RECV_DATA       0X01
  47#define GEN_STOP        0X02
  48#define RECV_DISCARD    0X03
  49#define GEN_START       0X04
  50#define START_NACK      0X05
  51#define START_HIGH      0X06
  52#define START_HIGH_NACK 0X07
  53
  54#define MCR_MEN         BIT(0)
  55#define MCR_RST         BIT(1)
  56#define MCR_DOZEN       BIT(2)
  57#define MCR_DBGEN       BIT(3)
  58#define MCR_RTF         BIT(8)
  59#define MCR_RRF         BIT(9)
  60#define MSR_TDF         BIT(0)
  61#define MSR_RDF         BIT(1)
  62#define MSR_SDF         BIT(9)
  63#define MSR_NDF         BIT(10)
  64#define MSR_ALF         BIT(11)
  65#define MSR_MBF         BIT(24)
  66#define MSR_BBF         BIT(25)
  67#define MIER_TDIE       BIT(0)
  68#define MIER_RDIE       BIT(1)
  69#define MIER_SDIE       BIT(9)
  70#define MIER_NDIE       BIT(10)
  71#define MCFGR1_AUTOSTOP BIT(8)
  72#define MCFGR1_IGNACK   BIT(9)
  73#define MRDR_RXEMPTY    BIT(14)
  74
  75#define I2C_CLK_RATIO   2
  76#define CHUNK_DATA      256
  77
  78#define LPI2C_DEFAULT_RATE      100000
  79#define STARDARD_MAX_BITRATE    400000
  80#define FAST_MAX_BITRATE        1000000
  81#define FAST_PLUS_MAX_BITRATE   3400000
  82#define HIGHSPEED_MAX_BITRATE   5000000
  83
  84#define I2C_PM_TIMEOUT          10 /* ms */
  85
  86enum lpi2c_imx_mode {
  87        STANDARD,       /* 100+Kbps */
  88        FAST,           /* 400+Kbps */
  89        FAST_PLUS,      /* 1.0+Mbps */
  90        HS,             /* 3.4+Mbps */
  91        ULTRA_FAST,     /* 5.0+Mbps */
  92};
  93
  94enum lpi2c_imx_pincfg {
  95        TWO_PIN_OD,
  96        TWO_PIN_OO,
  97        TWO_PIN_PP,
  98        FOUR_PIN_PP,
  99};
 100
 101struct lpi2c_imx_struct {
 102        struct i2c_adapter      adapter;
 103        struct clk              *clk;
 104        void __iomem            *base;
 105        __u8                    *rx_buf;
 106        __u8                    *tx_buf;
 107        struct completion       complete;
 108        unsigned int            msglen;
 109        unsigned int            delivered;
 110        unsigned int            block_data;
 111        unsigned int            bitrate;
 112        unsigned int            txfifosize;
 113        unsigned int            rxfifosize;
 114        enum lpi2c_imx_mode     mode;
 115};
 116
 117static void lpi2c_imx_intctrl(struct lpi2c_imx_struct *lpi2c_imx,
 118                              unsigned int enable)
 119{
 120        writel(enable, lpi2c_imx->base + LPI2C_MIER);
 121}
 122
 123static int lpi2c_imx_bus_busy(struct lpi2c_imx_struct *lpi2c_imx)
 124{
 125        unsigned long orig_jiffies = jiffies;
 126        unsigned int temp;
 127
 128        while (1) {
 129                temp = readl(lpi2c_imx->base + LPI2C_MSR);
 130
 131                /* check for arbitration lost, clear if set */
 132                if (temp & MSR_ALF) {
 133                        writel(temp, lpi2c_imx->base + LPI2C_MSR);
 134                        return -EAGAIN;
 135                }
 136
 137                if (temp & (MSR_BBF | MSR_MBF))
 138                        break;
 139
 140                if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 141                        dev_dbg(&lpi2c_imx->adapter.dev, "bus not work\n");
 142                        return -ETIMEDOUT;
 143                }
 144                schedule();
 145        }
 146
 147        return 0;
 148}
 149
 150static void lpi2c_imx_set_mode(struct lpi2c_imx_struct *lpi2c_imx)
 151{
 152        unsigned int bitrate = lpi2c_imx->bitrate;
 153        enum lpi2c_imx_mode mode;
 154
 155        if (bitrate < STARDARD_MAX_BITRATE)
 156                mode = STANDARD;
 157        else if (bitrate < FAST_MAX_BITRATE)
 158                mode = FAST;
 159        else if (bitrate < FAST_PLUS_MAX_BITRATE)
 160                mode = FAST_PLUS;
 161        else if (bitrate < HIGHSPEED_MAX_BITRATE)
 162                mode = HS;
 163        else
 164                mode = ULTRA_FAST;
 165
 166        lpi2c_imx->mode = mode;
 167}
 168
 169static int lpi2c_imx_start(struct lpi2c_imx_struct *lpi2c_imx,
 170                           struct i2c_msg *msgs)
 171{
 172        unsigned int temp;
 173
 174        temp = readl(lpi2c_imx->base + LPI2C_MCR);
 175        temp |= MCR_RRF | MCR_RTF;
 176        writel(temp, lpi2c_imx->base + LPI2C_MCR);
 177        writel(0x7f00, lpi2c_imx->base + LPI2C_MSR);
 178
 179        temp = i2c_8bit_addr_from_msg(msgs) | (GEN_START << 8);
 180        writel(temp, lpi2c_imx->base + LPI2C_MTDR);
 181
 182        return lpi2c_imx_bus_busy(lpi2c_imx);
 183}
 184
 185static void lpi2c_imx_stop(struct lpi2c_imx_struct *lpi2c_imx)
 186{
 187        unsigned long orig_jiffies = jiffies;
 188        unsigned int temp;
 189
 190        writel(GEN_STOP << 8, lpi2c_imx->base + LPI2C_MTDR);
 191
 192        do {
 193                temp = readl(lpi2c_imx->base + LPI2C_MSR);
 194                if (temp & MSR_SDF)
 195                        break;
 196
 197                if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 198                        dev_dbg(&lpi2c_imx->adapter.dev, "stop timeout\n");
 199                        break;
 200                }
 201                schedule();
 202
 203        } while (1);
 204}
 205
 206/* CLKLO = I2C_CLK_RATIO * CLKHI, SETHOLD = CLKHI, DATAVD = CLKHI/2 */
 207static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx)
 208{
 209        u8 prescale, filt, sethold, clkhi, clklo, datavd;
 210        unsigned int clk_rate, clk_cycle;
 211        enum lpi2c_imx_pincfg pincfg;
 212        unsigned int temp;
 213
 214        lpi2c_imx_set_mode(lpi2c_imx);
 215
 216        clk_rate = clk_get_rate(lpi2c_imx->clk);
 217        if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST)
 218                filt = 0;
 219        else
 220                filt = 2;
 221
 222        for (prescale = 0; prescale <= 7; prescale++) {
 223                clk_cycle = clk_rate / ((1 << prescale) * lpi2c_imx->bitrate)
 224                            - 3 - (filt >> 1);
 225                clkhi = (clk_cycle + I2C_CLK_RATIO) / (I2C_CLK_RATIO + 1);
 226                clklo = clk_cycle - clkhi;
 227                if (clklo < 64)
 228                        break;
 229        }
 230
 231        if (prescale > 7)
 232                return -EINVAL;
 233
 234        /* set MCFGR1: PINCFG, PRESCALE, IGNACK */
 235        if (lpi2c_imx->mode == ULTRA_FAST)
 236                pincfg = TWO_PIN_OO;
 237        else
 238                pincfg = TWO_PIN_OD;
 239        temp = prescale | pincfg << 24;
 240
 241        if (lpi2c_imx->mode == ULTRA_FAST)
 242                temp |= MCFGR1_IGNACK;
 243
 244        writel(temp, lpi2c_imx->base + LPI2C_MCFGR1);
 245
 246        /* set MCFGR2: FILTSDA, FILTSCL */
 247        temp = (filt << 16) | (filt << 24);
 248        writel(temp, lpi2c_imx->base + LPI2C_MCFGR2);
 249
 250        /* set MCCR: DATAVD, SETHOLD, CLKHI, CLKLO */
 251        sethold = clkhi;
 252        datavd = clkhi >> 1;
 253        temp = datavd << 24 | sethold << 16 | clkhi << 8 | clklo;
 254
 255        if (lpi2c_imx->mode == HS)
 256                writel(temp, lpi2c_imx->base + LPI2C_MCCR1);
 257        else
 258                writel(temp, lpi2c_imx->base + LPI2C_MCCR0);
 259
 260        return 0;
 261}
 262
 263static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx)
 264{
 265        unsigned int temp;
 266        int ret;
 267
 268        ret = pm_runtime_get_sync(lpi2c_imx->adapter.dev.parent);
 269        if (ret < 0)
 270                return ret;
 271
 272        temp = MCR_RST;
 273        writel(temp, lpi2c_imx->base + LPI2C_MCR);
 274        writel(0, lpi2c_imx->base + LPI2C_MCR);
 275
 276        ret = lpi2c_imx_config(lpi2c_imx);
 277        if (ret)
 278                goto rpm_put;
 279
 280        temp = readl(lpi2c_imx->base + LPI2C_MCR);
 281        temp |= MCR_MEN;
 282        writel(temp, lpi2c_imx->base + LPI2C_MCR);
 283
 284        return 0;
 285
 286rpm_put:
 287        pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
 288        pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
 289
 290        return ret;
 291}
 292
 293static int lpi2c_imx_master_disable(struct lpi2c_imx_struct *lpi2c_imx)
 294{
 295        u32 temp;
 296
 297        temp = readl(lpi2c_imx->base + LPI2C_MCR);
 298        temp &= ~MCR_MEN;
 299        writel(temp, lpi2c_imx->base + LPI2C_MCR);
 300
 301        pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
 302        pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
 303
 304        return 0;
 305}
 306
 307static int lpi2c_imx_msg_complete(struct lpi2c_imx_struct *lpi2c_imx)
 308{
 309        unsigned long timeout;
 310
 311        timeout = wait_for_completion_timeout(&lpi2c_imx->complete, HZ);
 312
 313        return timeout ? 0 : -ETIMEDOUT;
 314}
 315
 316static int lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct *lpi2c_imx)
 317{
 318        unsigned long orig_jiffies = jiffies;
 319        u32 txcnt;
 320
 321        do {
 322                txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
 323
 324                if (readl(lpi2c_imx->base + LPI2C_MSR) & MSR_NDF) {
 325                        dev_dbg(&lpi2c_imx->adapter.dev, "NDF detected\n");
 326                        return -EIO;
 327                }
 328
 329                if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 330                        dev_dbg(&lpi2c_imx->adapter.dev, "txfifo empty timeout\n");
 331                        return -ETIMEDOUT;
 332                }
 333                schedule();
 334
 335        } while (txcnt);
 336
 337        return 0;
 338}
 339
 340static void lpi2c_imx_set_tx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
 341{
 342        writel(lpi2c_imx->txfifosize >> 1, lpi2c_imx->base + LPI2C_MFCR);
 343}
 344
 345static void lpi2c_imx_set_rx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
 346{
 347        unsigned int temp, remaining;
 348
 349        remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
 350
 351        if (remaining > (lpi2c_imx->rxfifosize >> 1))
 352                temp = lpi2c_imx->rxfifosize >> 1;
 353        else
 354                temp = 0;
 355
 356        writel(temp << 16, lpi2c_imx->base + LPI2C_MFCR);
 357}
 358
 359static void lpi2c_imx_write_txfifo(struct lpi2c_imx_struct *lpi2c_imx)
 360{
 361        unsigned int data, txcnt;
 362
 363        txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
 364
 365        while (txcnt < lpi2c_imx->txfifosize) {
 366                if (lpi2c_imx->delivered == lpi2c_imx->msglen)
 367                        break;
 368
 369                data = lpi2c_imx->tx_buf[lpi2c_imx->delivered++];
 370                writel(data, lpi2c_imx->base + LPI2C_MTDR);
 371                txcnt++;
 372        }
 373
 374        if (lpi2c_imx->delivered < lpi2c_imx->msglen)
 375                lpi2c_imx_intctrl(lpi2c_imx, MIER_TDIE | MIER_NDIE);
 376        else
 377                complete(&lpi2c_imx->complete);
 378}
 379
 380static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx)
 381{
 382        unsigned int blocklen, remaining;
 383        unsigned int temp, data;
 384
 385        do {
 386                data = readl(lpi2c_imx->base + LPI2C_MRDR);
 387                if (data & MRDR_RXEMPTY)
 388                        break;
 389
 390                lpi2c_imx->rx_buf[lpi2c_imx->delivered++] = data & 0xff;
 391        } while (1);
 392
 393        /*
 394         * First byte is the length of remaining packet in the SMBus block
 395         * data read. Add it to msgs->len.
 396         */
 397        if (lpi2c_imx->block_data) {
 398                blocklen = lpi2c_imx->rx_buf[0];
 399                lpi2c_imx->msglen += blocklen;
 400        }
 401
 402        remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
 403
 404        if (!remaining) {
 405                complete(&lpi2c_imx->complete);
 406                return;
 407        }
 408
 409        /* not finished, still waiting for rx data */
 410        lpi2c_imx_set_rx_watermark(lpi2c_imx);
 411
 412        /* multiple receive commands */
 413        if (lpi2c_imx->block_data) {
 414                lpi2c_imx->block_data = 0;
 415                temp = remaining;
 416                temp |= (RECV_DATA << 8);
 417                writel(temp, lpi2c_imx->base + LPI2C_MTDR);
 418        } else if (!(lpi2c_imx->delivered & 0xff)) {
 419                temp = (remaining > CHUNK_DATA ? CHUNK_DATA : remaining) - 1;
 420                temp |= (RECV_DATA << 8);
 421                writel(temp, lpi2c_imx->base + LPI2C_MTDR);
 422        }
 423
 424        lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE);
 425}
 426
 427static void lpi2c_imx_write(struct lpi2c_imx_struct *lpi2c_imx,
 428                            struct i2c_msg *msgs)
 429{
 430        lpi2c_imx->tx_buf = msgs->buf;
 431        lpi2c_imx_set_tx_watermark(lpi2c_imx);
 432        lpi2c_imx_write_txfifo(lpi2c_imx);
 433}
 434
 435static void lpi2c_imx_read(struct lpi2c_imx_struct *lpi2c_imx,
 436                           struct i2c_msg *msgs)
 437{
 438        unsigned int temp;
 439
 440        lpi2c_imx->rx_buf = msgs->buf;
 441        lpi2c_imx->block_data = msgs->flags & I2C_M_RECV_LEN;
 442
 443        lpi2c_imx_set_rx_watermark(lpi2c_imx);
 444        temp = msgs->len > CHUNK_DATA ? CHUNK_DATA - 1 : msgs->len - 1;
 445        temp |= (RECV_DATA << 8);
 446        writel(temp, lpi2c_imx->base + LPI2C_MTDR);
 447
 448        lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE | MIER_NDIE);
 449}
 450
 451static int lpi2c_imx_xfer(struct i2c_adapter *adapter,
 452                          struct i2c_msg *msgs, int num)
 453{
 454        struct lpi2c_imx_struct *lpi2c_imx = i2c_get_adapdata(adapter);
 455        unsigned int temp;
 456        int i, result;
 457
 458        result = lpi2c_imx_master_enable(lpi2c_imx);
 459        if (result)
 460                return result;
 461
 462        for (i = 0; i < num; i++) {
 463                result = lpi2c_imx_start(lpi2c_imx, &msgs[i]);
 464                if (result)
 465                        goto disable;
 466
 467                /* quick smbus */
 468                if (num == 1 && msgs[0].len == 0)
 469                        goto stop;
 470
 471                lpi2c_imx->delivered = 0;
 472                lpi2c_imx->msglen = msgs[i].len;
 473                init_completion(&lpi2c_imx->complete);
 474
 475                if (msgs[i].flags & I2C_M_RD)
 476                        lpi2c_imx_read(lpi2c_imx, &msgs[i]);
 477                else
 478                        lpi2c_imx_write(lpi2c_imx, &msgs[i]);
 479
 480                result = lpi2c_imx_msg_complete(lpi2c_imx);
 481                if (result)
 482                        goto stop;
 483
 484                if (!(msgs[i].flags & I2C_M_RD)) {
 485                        result = lpi2c_imx_txfifo_empty(lpi2c_imx);
 486                        if (result)
 487                                goto stop;
 488                }
 489        }
 490
 491stop:
 492        lpi2c_imx_stop(lpi2c_imx);
 493
 494        temp = readl(lpi2c_imx->base + LPI2C_MSR);
 495        if ((temp & MSR_NDF) && !result)
 496                result = -EIO;
 497
 498disable:
 499        lpi2c_imx_master_disable(lpi2c_imx);
 500
 501        dev_dbg(&lpi2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
 502                (result < 0) ? "error" : "success msg",
 503                (result < 0) ? result : num);
 504
 505        return (result < 0) ? result : num;
 506}
 507
 508static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id)
 509{
 510        struct lpi2c_imx_struct *lpi2c_imx = dev_id;
 511        unsigned int temp;
 512
 513        lpi2c_imx_intctrl(lpi2c_imx, 0);
 514        temp = readl(lpi2c_imx->base + LPI2C_MSR);
 515
 516        if (temp & MSR_RDF)
 517                lpi2c_imx_read_rxfifo(lpi2c_imx);
 518
 519        if (temp & MSR_TDF)
 520                lpi2c_imx_write_txfifo(lpi2c_imx);
 521
 522        if (temp & MSR_NDF)
 523                complete(&lpi2c_imx->complete);
 524
 525        return IRQ_HANDLED;
 526}
 527
 528static u32 lpi2c_imx_func(struct i2c_adapter *adapter)
 529{
 530        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
 531                I2C_FUNC_SMBUS_READ_BLOCK_DATA;
 532}
 533
 534static const struct i2c_algorithm lpi2c_imx_algo = {
 535        .master_xfer    = lpi2c_imx_xfer,
 536        .functionality  = lpi2c_imx_func,
 537};
 538
 539static const struct of_device_id lpi2c_imx_of_match[] = {
 540        { .compatible = "fsl,imx7ulp-lpi2c" },
 541        { },
 542};
 543MODULE_DEVICE_TABLE(of, lpi2c_imx_of_match);
 544
 545static int lpi2c_imx_probe(struct platform_device *pdev)
 546{
 547        struct lpi2c_imx_struct *lpi2c_imx;
 548        unsigned int temp;
 549        int irq, ret;
 550
 551        lpi2c_imx = devm_kzalloc(&pdev->dev, sizeof(*lpi2c_imx), GFP_KERNEL);
 552        if (!lpi2c_imx)
 553                return -ENOMEM;
 554
 555        lpi2c_imx->base = devm_platform_ioremap_resource(pdev, 0);
 556        if (IS_ERR(lpi2c_imx->base))
 557                return PTR_ERR(lpi2c_imx->base);
 558
 559        irq = platform_get_irq(pdev, 0);
 560        if (irq < 0) {
 561                dev_err(&pdev->dev, "can't get irq number\n");
 562                return irq;
 563        }
 564
 565        lpi2c_imx->adapter.owner        = THIS_MODULE;
 566        lpi2c_imx->adapter.algo         = &lpi2c_imx_algo;
 567        lpi2c_imx->adapter.dev.parent   = &pdev->dev;
 568        lpi2c_imx->adapter.dev.of_node  = pdev->dev.of_node;
 569        strlcpy(lpi2c_imx->adapter.name, pdev->name,
 570                sizeof(lpi2c_imx->adapter.name));
 571
 572        lpi2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
 573        if (IS_ERR(lpi2c_imx->clk)) {
 574                dev_err(&pdev->dev, "can't get I2C peripheral clock\n");
 575                return PTR_ERR(lpi2c_imx->clk);
 576        }
 577
 578        ret = of_property_read_u32(pdev->dev.of_node,
 579                                   "clock-frequency", &lpi2c_imx->bitrate);
 580        if (ret)
 581                lpi2c_imx->bitrate = LPI2C_DEFAULT_RATE;
 582
 583        ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr, 0,
 584                               pdev->name, lpi2c_imx);
 585        if (ret) {
 586                dev_err(&pdev->dev, "can't claim irq %d\n", irq);
 587                return ret;
 588        }
 589
 590        i2c_set_adapdata(&lpi2c_imx->adapter, lpi2c_imx);
 591        platform_set_drvdata(pdev, lpi2c_imx);
 592
 593        ret = clk_prepare_enable(lpi2c_imx->clk);
 594        if (ret) {
 595                dev_err(&pdev->dev, "clk enable failed %d\n", ret);
 596                return ret;
 597        }
 598
 599        pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
 600        pm_runtime_use_autosuspend(&pdev->dev);
 601        pm_runtime_get_noresume(&pdev->dev);
 602        pm_runtime_set_active(&pdev->dev);
 603        pm_runtime_enable(&pdev->dev);
 604
 605        temp = readl(lpi2c_imx->base + LPI2C_PARAM);
 606        lpi2c_imx->txfifosize = 1 << (temp & 0x0f);
 607        lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f);
 608
 609        ret = i2c_add_adapter(&lpi2c_imx->adapter);
 610        if (ret)
 611                goto rpm_disable;
 612
 613        pm_runtime_mark_last_busy(&pdev->dev);
 614        pm_runtime_put_autosuspend(&pdev->dev);
 615
 616        dev_info(&lpi2c_imx->adapter.dev, "LPI2C adapter registered\n");
 617
 618        return 0;
 619
 620rpm_disable:
 621        pm_runtime_put(&pdev->dev);
 622        pm_runtime_disable(&pdev->dev);
 623        pm_runtime_dont_use_autosuspend(&pdev->dev);
 624
 625        return ret;
 626}
 627
 628static int lpi2c_imx_remove(struct platform_device *pdev)
 629{
 630        struct lpi2c_imx_struct *lpi2c_imx = platform_get_drvdata(pdev);
 631
 632        i2c_del_adapter(&lpi2c_imx->adapter);
 633
 634        pm_runtime_disable(&pdev->dev);
 635        pm_runtime_dont_use_autosuspend(&pdev->dev);
 636
 637        return 0;
 638}
 639
 640static int __maybe_unused lpi2c_runtime_suspend(struct device *dev)
 641{
 642        struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
 643
 644        clk_disable_unprepare(lpi2c_imx->clk);
 645        pinctrl_pm_select_sleep_state(dev);
 646
 647        return 0;
 648}
 649
 650static int __maybe_unused lpi2c_runtime_resume(struct device *dev)
 651{
 652        struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
 653        int ret;
 654
 655        pinctrl_pm_select_default_state(dev);
 656        ret = clk_prepare_enable(lpi2c_imx->clk);
 657        if (ret) {
 658                dev_err(dev, "failed to enable I2C clock, ret=%d\n", ret);
 659                return ret;
 660        }
 661
 662        return 0;
 663}
 664
 665static const struct dev_pm_ops lpi2c_pm_ops = {
 666        SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 667                                      pm_runtime_force_resume)
 668        SET_RUNTIME_PM_OPS(lpi2c_runtime_suspend,
 669                           lpi2c_runtime_resume, NULL)
 670};
 671
 672static struct platform_driver lpi2c_imx_driver = {
 673        .probe = lpi2c_imx_probe,
 674        .remove = lpi2c_imx_remove,
 675        .driver = {
 676                .name = DRIVER_NAME,
 677                .of_match_table = lpi2c_imx_of_match,
 678                .pm = &lpi2c_pm_ops,
 679        },
 680};
 681
 682module_platform_driver(lpi2c_imx_driver);
 683
 684MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>");
 685MODULE_DESCRIPTION("I2C adapter driver for LPI2C bus");
 686MODULE_LICENSE("GPL");
 687