linux/drivers/i2c/busses/i2c-imx-lpi2c.c
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   1/*
   2 * This is i.MX low power i2c controller driver.
   3 *
   4 * Copyright 2016 Freescale Semiconductor, Inc.
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License
   8 * as published by the Free Software Foundation; either version 2
   9 * of the License, or (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 */
  17
  18#include <linux/clk.h>
  19#include <linux/completion.h>
  20#include <linux/delay.h>
  21#include <linux/err.h>
  22#include <linux/errno.h>
  23#include <linux/i2c.h>
  24#include <linux/init.h>
  25#include <linux/interrupt.h>
  26#include <linux/io.h>
  27#include <linux/kernel.h>
  28#include <linux/module.h>
  29#include <linux/of.h>
  30#include <linux/of_device.h>
  31#include <linux/pinctrl/consumer.h>
  32#include <linux/platform_device.h>
  33#include <linux/pm_runtime.h>
  34#include <linux/sched.h>
  35#include <linux/slab.h>
  36
  37#define DRIVER_NAME "imx-lpi2c"
  38
  39#define LPI2C_PARAM     0x04    /* i2c RX/TX FIFO size */
  40#define LPI2C_MCR       0x10    /* i2c contrl register */
  41#define LPI2C_MSR       0x14    /* i2c status register */
  42#define LPI2C_MIER      0x18    /* i2c interrupt enable */
  43#define LPI2C_MCFGR0    0x20    /* i2c master configuration */
  44#define LPI2C_MCFGR1    0x24    /* i2c master configuration */
  45#define LPI2C_MCFGR2    0x28    /* i2c master configuration */
  46#define LPI2C_MCFGR3    0x2C    /* i2c master configuration */
  47#define LPI2C_MCCR0     0x48    /* i2c master clk configuration */
  48#define LPI2C_MCCR1     0x50    /* i2c master clk configuration */
  49#define LPI2C_MFCR      0x58    /* i2c master FIFO control */
  50#define LPI2C_MFSR      0x5C    /* i2c master FIFO status */
  51#define LPI2C_MTDR      0x60    /* i2c master TX data register */
  52#define LPI2C_MRDR      0x70    /* i2c master RX data register */
  53
  54/* i2c command */
  55#define TRAN_DATA       0X00
  56#define RECV_DATA       0X01
  57#define GEN_STOP        0X02
  58#define RECV_DISCARD    0X03
  59#define GEN_START       0X04
  60#define START_NACK      0X05
  61#define START_HIGH      0X06
  62#define START_HIGH_NACK 0X07
  63
  64#define MCR_MEN         BIT(0)
  65#define MCR_RST         BIT(1)
  66#define MCR_DOZEN       BIT(2)
  67#define MCR_DBGEN       BIT(3)
  68#define MCR_RTF         BIT(8)
  69#define MCR_RRF         BIT(9)
  70#define MSR_TDF         BIT(0)
  71#define MSR_RDF         BIT(1)
  72#define MSR_SDF         BIT(9)
  73#define MSR_NDF         BIT(10)
  74#define MSR_ALF         BIT(11)
  75#define MSR_MBF         BIT(24)
  76#define MSR_BBF         BIT(25)
  77#define MIER_TDIE       BIT(0)
  78#define MIER_RDIE       BIT(1)
  79#define MIER_SDIE       BIT(9)
  80#define MIER_NDIE       BIT(10)
  81#define MCFGR1_AUTOSTOP BIT(8)
  82#define MCFGR1_IGNACK   BIT(9)
  83#define MRDR_RXEMPTY    BIT(14)
  84
  85#define I2C_CLK_RATIO   2
  86#define CHUNK_DATA      256
  87
  88#define LPI2C_DEFAULT_RATE      100000
  89#define STARDARD_MAX_BITRATE    400000
  90#define FAST_MAX_BITRATE        1000000
  91#define FAST_PLUS_MAX_BITRATE   3400000
  92#define HIGHSPEED_MAX_BITRATE   5000000
  93
  94#define I2C_PM_TIMEOUT          10 /* ms */
  95
  96enum lpi2c_imx_mode {
  97        STANDARD,       /* 100+Kbps */
  98        FAST,           /* 400+Kbps */
  99        FAST_PLUS,      /* 1.0+Mbps */
 100        HS,             /* 3.4+Mbps */
 101        ULTRA_FAST,     /* 5.0+Mbps */
 102};
 103
 104enum lpi2c_imx_pincfg {
 105        TWO_PIN_OD,
 106        TWO_PIN_OO,
 107        TWO_PIN_PP,
 108        FOUR_PIN_PP,
 109};
 110
 111struct lpi2c_imx_struct {
 112        struct i2c_adapter      adapter;
 113        struct clk              *clk;
 114        void __iomem            *base;
 115        __u8                    *rx_buf;
 116        __u8                    *tx_buf;
 117        struct completion       complete;
 118        unsigned int            msglen;
 119        unsigned int            delivered;
 120        unsigned int            block_data;
 121        unsigned int            bitrate;
 122        unsigned int            txfifosize;
 123        unsigned int            rxfifosize;
 124        enum lpi2c_imx_mode     mode;
 125};
 126
 127static void lpi2c_imx_intctrl(struct lpi2c_imx_struct *lpi2c_imx,
 128                              unsigned int enable)
 129{
 130        writel(enable, lpi2c_imx->base + LPI2C_MIER);
 131}
 132
 133static int lpi2c_imx_bus_busy(struct lpi2c_imx_struct *lpi2c_imx)
 134{
 135        unsigned long orig_jiffies = jiffies;
 136        unsigned int temp;
 137
 138        while (1) {
 139                temp = readl(lpi2c_imx->base + LPI2C_MSR);
 140
 141                /* check for arbitration lost, clear if set */
 142                if (temp & MSR_ALF) {
 143                        writel(temp, lpi2c_imx->base + LPI2C_MSR);
 144                        return -EAGAIN;
 145                }
 146
 147                if (temp & (MSR_BBF | MSR_MBF))
 148                        break;
 149
 150                if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 151                        dev_dbg(&lpi2c_imx->adapter.dev, "bus not work\n");
 152                        return -ETIMEDOUT;
 153                }
 154                schedule();
 155        }
 156
 157        return 0;
 158}
 159
 160static void lpi2c_imx_set_mode(struct lpi2c_imx_struct *lpi2c_imx)
 161{
 162        unsigned int bitrate = lpi2c_imx->bitrate;
 163        enum lpi2c_imx_mode mode;
 164
 165        if (bitrate < STARDARD_MAX_BITRATE)
 166                mode = STANDARD;
 167        else if (bitrate < FAST_MAX_BITRATE)
 168                mode = FAST;
 169        else if (bitrate < FAST_PLUS_MAX_BITRATE)
 170                mode = FAST_PLUS;
 171        else if (bitrate < HIGHSPEED_MAX_BITRATE)
 172                mode = HS;
 173        else
 174                mode = ULTRA_FAST;
 175
 176        lpi2c_imx->mode = mode;
 177}
 178
 179static int lpi2c_imx_start(struct lpi2c_imx_struct *lpi2c_imx,
 180                           struct i2c_msg *msgs)
 181{
 182        unsigned int temp;
 183        u8 read;
 184
 185        temp = readl(lpi2c_imx->base + LPI2C_MCR);
 186        temp |= MCR_RRF | MCR_RTF;
 187        writel(temp, lpi2c_imx->base + LPI2C_MCR);
 188        writel(0x7f00, lpi2c_imx->base + LPI2C_MSR);
 189
 190        read = msgs->flags & I2C_M_RD;
 191        temp = (msgs->addr << 1 | read) | (GEN_START << 8);
 192        writel(temp, lpi2c_imx->base + LPI2C_MTDR);
 193
 194        return lpi2c_imx_bus_busy(lpi2c_imx);
 195}
 196
 197static void lpi2c_imx_stop(struct lpi2c_imx_struct *lpi2c_imx)
 198{
 199        unsigned long orig_jiffies = jiffies;
 200        unsigned int temp;
 201
 202        writel(GEN_STOP << 8, lpi2c_imx->base + LPI2C_MTDR);
 203
 204        do {
 205                temp = readl(lpi2c_imx->base + LPI2C_MSR);
 206                if (temp & MSR_SDF)
 207                        break;
 208
 209                if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 210                        dev_dbg(&lpi2c_imx->adapter.dev, "stop timeout\n");
 211                        break;
 212                }
 213                schedule();
 214
 215        } while (1);
 216}
 217
 218/* CLKLO = I2C_CLK_RATIO * CLKHI, SETHOLD = CLKHI, DATAVD = CLKHI/2 */
 219static int lpi2c_imx_config(struct lpi2c_imx_struct *lpi2c_imx)
 220{
 221        u8 prescale, filt, sethold, clkhi, clklo, datavd;
 222        unsigned int clk_rate, clk_cycle;
 223        enum lpi2c_imx_pincfg pincfg;
 224        unsigned int temp;
 225
 226        lpi2c_imx_set_mode(lpi2c_imx);
 227
 228        clk_rate = clk_get_rate(lpi2c_imx->clk);
 229        if (lpi2c_imx->mode == HS || lpi2c_imx->mode == ULTRA_FAST)
 230                filt = 0;
 231        else
 232                filt = 2;
 233
 234        for (prescale = 0; prescale <= 7; prescale++) {
 235                clk_cycle = clk_rate / ((1 << prescale) * lpi2c_imx->bitrate)
 236                            - 3 - (filt >> 1);
 237                clkhi = (clk_cycle + I2C_CLK_RATIO) / (I2C_CLK_RATIO + 1);
 238                clklo = clk_cycle - clkhi;
 239                if (clklo < 64)
 240                        break;
 241        }
 242
 243        if (prescale > 7)
 244                return -EINVAL;
 245
 246        /* set MCFGR1: PINCFG, PRESCALE, IGNACK */
 247        if (lpi2c_imx->mode == ULTRA_FAST)
 248                pincfg = TWO_PIN_OO;
 249        else
 250                pincfg = TWO_PIN_OD;
 251        temp = prescale | pincfg << 24;
 252
 253        if (lpi2c_imx->mode == ULTRA_FAST)
 254                temp |= MCFGR1_IGNACK;
 255
 256        writel(temp, lpi2c_imx->base + LPI2C_MCFGR1);
 257
 258        /* set MCFGR2: FILTSDA, FILTSCL */
 259        temp = (filt << 16) | (filt << 24);
 260        writel(temp, lpi2c_imx->base + LPI2C_MCFGR2);
 261
 262        /* set MCCR: DATAVD, SETHOLD, CLKHI, CLKLO */
 263        sethold = clkhi;
 264        datavd = clkhi >> 1;
 265        temp = datavd << 24 | sethold << 16 | clkhi << 8 | clklo;
 266
 267        if (lpi2c_imx->mode == HS)
 268                writel(temp, lpi2c_imx->base + LPI2C_MCCR1);
 269        else
 270                writel(temp, lpi2c_imx->base + LPI2C_MCCR0);
 271
 272        return 0;
 273}
 274
 275static int lpi2c_imx_master_enable(struct lpi2c_imx_struct *lpi2c_imx)
 276{
 277        unsigned int temp;
 278        int ret;
 279
 280        ret = pm_runtime_get_sync(lpi2c_imx->adapter.dev.parent);
 281        if (ret < 0)
 282                return ret;
 283
 284        temp = MCR_RST;
 285        writel(temp, lpi2c_imx->base + LPI2C_MCR);
 286        writel(0, lpi2c_imx->base + LPI2C_MCR);
 287
 288        ret = lpi2c_imx_config(lpi2c_imx);
 289        if (ret)
 290                goto rpm_put;
 291
 292        temp = readl(lpi2c_imx->base + LPI2C_MCR);
 293        temp |= MCR_MEN;
 294        writel(temp, lpi2c_imx->base + LPI2C_MCR);
 295
 296        return 0;
 297
 298rpm_put:
 299        pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
 300        pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
 301
 302        return ret;
 303}
 304
 305static int lpi2c_imx_master_disable(struct lpi2c_imx_struct *lpi2c_imx)
 306{
 307        u32 temp;
 308
 309        temp = readl(lpi2c_imx->base + LPI2C_MCR);
 310        temp &= ~MCR_MEN;
 311        writel(temp, lpi2c_imx->base + LPI2C_MCR);
 312
 313        pm_runtime_mark_last_busy(lpi2c_imx->adapter.dev.parent);
 314        pm_runtime_put_autosuspend(lpi2c_imx->adapter.dev.parent);
 315
 316        return 0;
 317}
 318
 319static int lpi2c_imx_msg_complete(struct lpi2c_imx_struct *lpi2c_imx)
 320{
 321        unsigned long timeout;
 322
 323        timeout = wait_for_completion_timeout(&lpi2c_imx->complete, HZ);
 324
 325        return timeout ? 0 : -ETIMEDOUT;
 326}
 327
 328static int lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct *lpi2c_imx)
 329{
 330        unsigned long orig_jiffies = jiffies;
 331        u32 txcnt;
 332
 333        do {
 334                txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
 335
 336                if (readl(lpi2c_imx->base + LPI2C_MSR) & MSR_NDF) {
 337                        dev_dbg(&lpi2c_imx->adapter.dev, "NDF detected\n");
 338                        return -EIO;
 339                }
 340
 341                if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 342                        dev_dbg(&lpi2c_imx->adapter.dev, "txfifo empty timeout\n");
 343                        return -ETIMEDOUT;
 344                }
 345                schedule();
 346
 347        } while (txcnt);
 348
 349        return 0;
 350}
 351
 352static void lpi2c_imx_set_tx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
 353{
 354        writel(lpi2c_imx->txfifosize >> 1, lpi2c_imx->base + LPI2C_MFCR);
 355}
 356
 357static void lpi2c_imx_set_rx_watermark(struct lpi2c_imx_struct *lpi2c_imx)
 358{
 359        unsigned int temp, remaining;
 360
 361        remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
 362
 363        if (remaining > (lpi2c_imx->rxfifosize >> 1))
 364                temp = lpi2c_imx->rxfifosize >> 1;
 365        else
 366                temp = 0;
 367
 368        writel(temp << 16, lpi2c_imx->base + LPI2C_MFCR);
 369}
 370
 371static void lpi2c_imx_write_txfifo(struct lpi2c_imx_struct *lpi2c_imx)
 372{
 373        unsigned int data, txcnt;
 374
 375        txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;
 376
 377        while (txcnt < lpi2c_imx->txfifosize) {
 378                if (lpi2c_imx->delivered == lpi2c_imx->msglen)
 379                        break;
 380
 381                data = lpi2c_imx->tx_buf[lpi2c_imx->delivered++];
 382                writel(data, lpi2c_imx->base + LPI2C_MTDR);
 383                txcnt++;
 384        }
 385
 386        if (lpi2c_imx->delivered < lpi2c_imx->msglen)
 387                lpi2c_imx_intctrl(lpi2c_imx, MIER_TDIE | MIER_NDIE);
 388        else
 389                complete(&lpi2c_imx->complete);
 390}
 391
 392static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx)
 393{
 394        unsigned int blocklen, remaining;
 395        unsigned int temp, data;
 396
 397        do {
 398                data = readl(lpi2c_imx->base + LPI2C_MRDR);
 399                if (data & MRDR_RXEMPTY)
 400                        break;
 401
 402                lpi2c_imx->rx_buf[lpi2c_imx->delivered++] = data & 0xff;
 403        } while (1);
 404
 405        /*
 406         * First byte is the length of remaining packet in the SMBus block
 407         * data read. Add it to msgs->len.
 408         */
 409        if (lpi2c_imx->block_data) {
 410                blocklen = lpi2c_imx->rx_buf[0];
 411                lpi2c_imx->msglen += blocklen;
 412        }
 413
 414        remaining = lpi2c_imx->msglen - lpi2c_imx->delivered;
 415
 416        if (!remaining) {
 417                complete(&lpi2c_imx->complete);
 418                return;
 419        }
 420
 421        /* not finished, still waiting for rx data */
 422        lpi2c_imx_set_rx_watermark(lpi2c_imx);
 423
 424        /* multiple receive commands */
 425        if (lpi2c_imx->block_data) {
 426                lpi2c_imx->block_data = 0;
 427                temp = remaining;
 428                temp |= (RECV_DATA << 8);
 429                writel(temp, lpi2c_imx->base + LPI2C_MTDR);
 430        } else if (!(lpi2c_imx->delivered & 0xff)) {
 431                temp = (remaining > CHUNK_DATA ? CHUNK_DATA : remaining) - 1;
 432                temp |= (RECV_DATA << 8);
 433                writel(temp, lpi2c_imx->base + LPI2C_MTDR);
 434        }
 435
 436        lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE);
 437}
 438
 439static void lpi2c_imx_write(struct lpi2c_imx_struct *lpi2c_imx,
 440                            struct i2c_msg *msgs)
 441{
 442        lpi2c_imx->tx_buf = msgs->buf;
 443        lpi2c_imx_set_tx_watermark(lpi2c_imx);
 444        lpi2c_imx_write_txfifo(lpi2c_imx);
 445}
 446
 447static void lpi2c_imx_read(struct lpi2c_imx_struct *lpi2c_imx,
 448                           struct i2c_msg *msgs)
 449{
 450        unsigned int temp;
 451
 452        lpi2c_imx->rx_buf = msgs->buf;
 453        lpi2c_imx->block_data = msgs->flags & I2C_M_RECV_LEN;
 454
 455        lpi2c_imx_set_rx_watermark(lpi2c_imx);
 456        temp = msgs->len > CHUNK_DATA ? CHUNK_DATA - 1 : msgs->len - 1;
 457        temp |= (RECV_DATA << 8);
 458        writel(temp, lpi2c_imx->base + LPI2C_MTDR);
 459
 460        lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE | MIER_NDIE);
 461}
 462
 463static int lpi2c_imx_xfer(struct i2c_adapter *adapter,
 464                          struct i2c_msg *msgs, int num)
 465{
 466        struct lpi2c_imx_struct *lpi2c_imx = i2c_get_adapdata(adapter);
 467        unsigned int temp;
 468        int i, result;
 469
 470        result = lpi2c_imx_master_enable(lpi2c_imx);
 471        if (result)
 472                return result;
 473
 474        for (i = 0; i < num; i++) {
 475                result = lpi2c_imx_start(lpi2c_imx, &msgs[i]);
 476                if (result)
 477                        goto disable;
 478
 479                /* quick smbus */
 480                if (num == 1 && msgs[0].len == 0)
 481                        goto stop;
 482
 483                lpi2c_imx->delivered = 0;
 484                lpi2c_imx->msglen = msgs[i].len;
 485                init_completion(&lpi2c_imx->complete);
 486
 487                if (msgs[i].flags & I2C_M_RD)
 488                        lpi2c_imx_read(lpi2c_imx, &msgs[i]);
 489                else
 490                        lpi2c_imx_write(lpi2c_imx, &msgs[i]);
 491
 492                result = lpi2c_imx_msg_complete(lpi2c_imx);
 493                if (result)
 494                        goto stop;
 495
 496                if (!(msgs[i].flags & I2C_M_RD)) {
 497                        result = lpi2c_imx_txfifo_empty(lpi2c_imx);
 498                        if (result)
 499                                goto stop;
 500                }
 501        }
 502
 503stop:
 504        lpi2c_imx_stop(lpi2c_imx);
 505
 506        temp = readl(lpi2c_imx->base + LPI2C_MSR);
 507        if ((temp & MSR_NDF) && !result)
 508                result = -EIO;
 509
 510disable:
 511        lpi2c_imx_master_disable(lpi2c_imx);
 512
 513        dev_dbg(&lpi2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
 514                (result < 0) ? "error" : "success msg",
 515                (result < 0) ? result : num);
 516
 517        return (result < 0) ? result : num;
 518}
 519
 520static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id)
 521{
 522        struct lpi2c_imx_struct *lpi2c_imx = dev_id;
 523        unsigned int temp;
 524
 525        lpi2c_imx_intctrl(lpi2c_imx, 0);
 526        temp = readl(lpi2c_imx->base + LPI2C_MSR);
 527
 528        if (temp & MSR_RDF)
 529                lpi2c_imx_read_rxfifo(lpi2c_imx);
 530
 531        if (temp & MSR_TDF)
 532                lpi2c_imx_write_txfifo(lpi2c_imx);
 533
 534        if (temp & MSR_NDF)
 535                complete(&lpi2c_imx->complete);
 536
 537        return IRQ_HANDLED;
 538}
 539
 540static u32 lpi2c_imx_func(struct i2c_adapter *adapter)
 541{
 542        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
 543                I2C_FUNC_SMBUS_READ_BLOCK_DATA;
 544}
 545
 546static const struct i2c_algorithm lpi2c_imx_algo = {
 547        .master_xfer    = lpi2c_imx_xfer,
 548        .functionality  = lpi2c_imx_func,
 549};
 550
 551static const struct of_device_id lpi2c_imx_of_match[] = {
 552        { .compatible = "fsl,imx7ulp-lpi2c" },
 553        { .compatible = "fsl,imx8dv-lpi2c" },
 554        { },
 555};
 556MODULE_DEVICE_TABLE(of, lpi2c_imx_of_match);
 557
 558static int lpi2c_imx_probe(struct platform_device *pdev)
 559{
 560        struct lpi2c_imx_struct *lpi2c_imx;
 561        struct resource *res;
 562        unsigned int temp;
 563        int irq, ret;
 564
 565        lpi2c_imx = devm_kzalloc(&pdev->dev, sizeof(*lpi2c_imx), GFP_KERNEL);
 566        if (!lpi2c_imx)
 567                return -ENOMEM;
 568
 569        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 570        lpi2c_imx->base = devm_ioremap_resource(&pdev->dev, res);
 571        if (IS_ERR(lpi2c_imx->base))
 572                return PTR_ERR(lpi2c_imx->base);
 573
 574        irq = platform_get_irq(pdev, 0);
 575        if (irq < 0) {
 576                dev_err(&pdev->dev, "can't get irq number\n");
 577                return irq;
 578        }
 579
 580        lpi2c_imx->adapter.owner        = THIS_MODULE;
 581        lpi2c_imx->adapter.algo         = &lpi2c_imx_algo;
 582        lpi2c_imx->adapter.dev.parent   = &pdev->dev;
 583        lpi2c_imx->adapter.dev.of_node  = pdev->dev.of_node;
 584        strlcpy(lpi2c_imx->adapter.name, pdev->name,
 585                sizeof(lpi2c_imx->adapter.name));
 586
 587        lpi2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
 588        if (IS_ERR(lpi2c_imx->clk)) {
 589                dev_err(&pdev->dev, "can't get I2C peripheral clock\n");
 590                return PTR_ERR(lpi2c_imx->clk);
 591        }
 592
 593        ret = of_property_read_u32(pdev->dev.of_node,
 594                                   "clock-frequency", &lpi2c_imx->bitrate);
 595        if (ret)
 596                lpi2c_imx->bitrate = LPI2C_DEFAULT_RATE;
 597
 598        ret = devm_request_irq(&pdev->dev, irq, lpi2c_imx_isr, 0,
 599                               pdev->name, lpi2c_imx);
 600        if (ret) {
 601                dev_err(&pdev->dev, "can't claim irq %d\n", irq);
 602                return ret;
 603        }
 604
 605        i2c_set_adapdata(&lpi2c_imx->adapter, lpi2c_imx);
 606        platform_set_drvdata(pdev, lpi2c_imx);
 607
 608        ret = clk_prepare_enable(lpi2c_imx->clk);
 609        if (ret) {
 610                dev_err(&pdev->dev, "clk enable failed %d\n", ret);
 611                return ret;
 612        }
 613
 614        pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
 615        pm_runtime_use_autosuspend(&pdev->dev);
 616        pm_runtime_get_noresume(&pdev->dev);
 617        pm_runtime_set_active(&pdev->dev);
 618        pm_runtime_enable(&pdev->dev);
 619
 620        temp = readl(lpi2c_imx->base + LPI2C_PARAM);
 621        lpi2c_imx->txfifosize = 1 << (temp & 0x0f);
 622        lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f);
 623
 624        ret = i2c_add_adapter(&lpi2c_imx->adapter);
 625        if (ret)
 626                goto rpm_disable;
 627
 628        pm_runtime_mark_last_busy(&pdev->dev);
 629        pm_runtime_put_autosuspend(&pdev->dev);
 630
 631        dev_info(&lpi2c_imx->adapter.dev, "LPI2C adapter registered\n");
 632
 633        return 0;
 634
 635rpm_disable:
 636        pm_runtime_put(&pdev->dev);
 637        pm_runtime_disable(&pdev->dev);
 638        pm_runtime_dont_use_autosuspend(&pdev->dev);
 639
 640        return ret;
 641}
 642
 643static int lpi2c_imx_remove(struct platform_device *pdev)
 644{
 645        struct lpi2c_imx_struct *lpi2c_imx = platform_get_drvdata(pdev);
 646
 647        i2c_del_adapter(&lpi2c_imx->adapter);
 648
 649        pm_runtime_disable(&pdev->dev);
 650        pm_runtime_dont_use_autosuspend(&pdev->dev);
 651
 652        return 0;
 653}
 654
 655#ifdef CONFIG_PM_SLEEP
 656static int lpi2c_runtime_suspend(struct device *dev)
 657{
 658        struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
 659
 660        clk_disable_unprepare(lpi2c_imx->clk);
 661        pinctrl_pm_select_sleep_state(dev);
 662
 663        return 0;
 664}
 665
 666static int lpi2c_runtime_resume(struct device *dev)
 667{
 668        struct lpi2c_imx_struct *lpi2c_imx = dev_get_drvdata(dev);
 669        int ret;
 670
 671        pinctrl_pm_select_default_state(dev);
 672        ret = clk_prepare_enable(lpi2c_imx->clk);
 673        if (ret) {
 674                dev_err(dev, "failed to enable I2C clock, ret=%d\n", ret);
 675                return ret;
 676        }
 677
 678        return 0;
 679}
 680
 681static const struct dev_pm_ops lpi2c_pm_ops = {
 682        SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
 683                                      pm_runtime_force_resume)
 684        SET_RUNTIME_PM_OPS(lpi2c_runtime_suspend,
 685                           lpi2c_runtime_resume, NULL)
 686};
 687#define IMX_LPI2C_PM      (&lpi2c_pm_ops)
 688#else
 689#define IMX_LPI2C_PM      NULL
 690#endif
 691
 692static struct platform_driver lpi2c_imx_driver = {
 693        .probe = lpi2c_imx_probe,
 694        .remove = lpi2c_imx_remove,
 695        .driver = {
 696                .name = DRIVER_NAME,
 697                .of_match_table = lpi2c_imx_of_match,
 698                .pm = IMX_LPI2C_PM,
 699        },
 700};
 701
 702module_platform_driver(lpi2c_imx_driver);
 703
 704MODULE_AUTHOR("Gao Pan <pandy.gao@nxp.com>");
 705MODULE_DESCRIPTION("I2C adapter driver for LPI2C bus");
 706MODULE_LICENSE("GPL");
 707