drivers/i2c/busses/i2c-imx.c

   1 /*
   2  *      Copyright (C) 2002 Motorola GSG-China
   3  *
   4  *      This program is free software; you can redistribute it and/or
   5  *      modify it under the terms of the GNU General Public License
   6  *      as published by the Free Software Foundation; either version 2
   7  *      of the License, or (at your option) any later version.
   8  *
   9  *      This program is distributed in the hope that it will be useful,
  10  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *      GNU General Public License for more details.
  13  *
  14  * Author:
  15  *      Darius Augulis, Teltonika Inc.
  16  *
  17  * Desc.:
  18  *      Implementation of I2C Adapter/Algorithm Driver
  19  *      for I2C Bus integrated in Freescale i.MX/MXC processors
  20  *
  21  *      Derived from Motorola GSG China I2C example driver
  22  *
  23  *      Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de
  24  *      Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de
  25  *      Copyright (C) 2007 RightHand Technologies, Inc.
  26  *      Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
  27  *
  28  *      Copyright 2013 Freescale Semiconductor, Inc.
  29  *
  30  */
  31
  32 #include <linux/clk.h>
  33 #include <linux/completion.h>
  34 #include <linux/delay.h>
  35 #include <linux/dma-mapping.h>
  36 #include <linux/dmaengine.h>
  37 #include <linux/dmapool.h>
  38 #include <linux/err.h>
  39 #include <linux/errno.h>
  40 #include <linux/i2c.h>
  41 #include <linux/init.h>
  42 #include <linux/interrupt.h>
  43 #include <linux/io.h>
  44 #include <linux/kernel.h>
  45 #include <linux/module.h>
  46 #include <linux/of.h>
  47 #include <linux/of_device.h>
  48 #include <linux/of_dma.h>
  49 #include <linux/of_gpio.h>
  50 #include <linux/pinctrl/consumer.h>
  51 #include <linux/platform_data/i2c-imx.h>
  52 #include <linux/platform_device.h>
  53 #include <linux/pm_runtime.h>
  54 #include <linux/sched.h>
  55 #include <linux/slab.h>
  56
  57 /* This will be the driver name the kernel reports */
  58 #define DRIVER_NAME "imx-i2c"
  59
  60 /* Default value */
  61 #define IMX_I2C_BIT_RATE        100000  /* 100kHz */
  62
  63 /*
  64  * Enable DMA if transfer byte size is bigger than this threshold.
  65  * As the hardware request, it must bigger than 4 bytes.\
  66  * I have set '16' here, maybe it's not the best but I think it's
  67  * the appropriate.
  68  */
  69 #define DMA_THRESHOLD   16
  70 #define DMA_TIMEOUT     1000
  71
  72 /* IMX I2C registers:
  73  * the I2C register offset is different between SoCs,
  74  * to provid support for all these chips, split the
  75  * register offset into a fixed base address and a
  76  * variable shift value, then the full register offset
  77  * will be calculated by
  78  * reg_off = ( reg_base_addr << reg_shift)
  79  */
  80 #define IMX_I2C_IADR    0x00    /* i2c slave address */
  81 #define IMX_I2C_IFDR    0x01    /* i2c frequency divider */
  82 #define IMX_I2C_I2CR    0x02    /* i2c control */
  83 #define IMX_I2C_I2SR    0x03    /* i2c status */
  84 #define IMX_I2C_I2DR    0x04    /* i2c transfer data */
  85
  86 #define IMX_I2C_REGSHIFT        2
  87 #define VF610_I2C_REGSHIFT      0
  88
  89 /* Bits of IMX I2C registers */
  90 #define I2SR_RXAK       0x01
  91 #define I2SR_IIF        0x02
  92 #define I2SR_SRW        0x04
  93 #define I2SR_IAL        0x10
  94 #define I2SR_IBB        0x20
  95 #define I2SR_IAAS       0x40
  96 #define I2SR_ICF        0x80
  97 #define I2CR_DMAEN      0x02
  98 #define I2CR_RSTA       0x04
  99 #define I2CR_TXAK       0x08
 100 #define I2CR_MTX        0x10
 101 #define I2CR_MSTA       0x20
 102 #define I2CR_IIEN       0x40
 103 #define I2CR_IEN        0x80
 104
 105 /* register bits different operating codes definition:
 106  * 1) I2SR: Interrupt flags clear operation differ between SoCs:
 107  * - write zero to clear(w0c) INT flag on i.MX,
 108  * - but write one to clear(w1c) INT flag on Vybrid.
 109  * 2) I2CR: I2C module enable operation also differ between SoCs:
 110  * - set I2CR_IEN bit enable the module on i.MX,
 111  * - but clear I2CR_IEN bit enable the module on Vybrid.
 112  */
 113 #define I2SR_CLR_OPCODE_W0C     0x0
 114 #define I2SR_CLR_OPCODE_W1C     (I2SR_IAL | I2SR_IIF)
 115 #define I2CR_IEN_OPCODE_0       0x0
 116 #define I2CR_IEN_OPCODE_1       I2CR_IEN
 117
 118 #define I2C_PM_TIMEOUT          10 /* ms */
 119
 120 /*
 121  * sorted list of clock divider, register value pairs
 122  * taken from table 26-5, p.26-9, Freescale i.MX
 123  * Integrated Portable System Processor Reference Manual
 124  * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
 125  *
 126  * Duplicated divider values removed from list
 127  */
 128 struct imx_i2c_clk_pair {
 129         u16     div;
 130         u16     val;
 131 };
 132
 133 static struct imx_i2c_clk_pair imx_i2c_clk_div[] = {
 134         { 22,   0x20 }, { 24,   0x21 }, { 26,   0x22 }, { 28,   0x23 },
 135         { 30,   0x00 }, { 32,   0x24 }, { 36,   0x25 }, { 40,   0x26 },
 136         { 42,   0x03 }, { 44,   0x27 }, { 48,   0x28 }, { 52,   0x05 },
 137         { 56,   0x29 }, { 60,   0x06 }, { 64,   0x2A }, { 72,   0x2B },
 138         { 80,   0x2C }, { 88,   0x09 }, { 96,   0x2D }, { 104,  0x0A },
 139         { 112,  0x2E }, { 128,  0x2F }, { 144,  0x0C }, { 160,  0x30 },
 140         { 192,  0x31 }, { 224,  0x32 }, { 240,  0x0F }, { 256,  0x33 },
 141         { 288,  0x10 }, { 320,  0x34 }, { 384,  0x35 }, { 448,  0x36 },
 142         { 480,  0x13 }, { 512,  0x37 }, { 576,  0x14 }, { 640,  0x38 },
 143         { 768,  0x39 }, { 896,  0x3A }, { 960,  0x17 }, { 1024, 0x3B },
 144         { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E },
 145         { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D },
 146         { 3072, 0x1E }, { 3840, 0x1F }
 147 };
 148
 149 /* Vybrid VF610 clock divider, register value pairs */
 150 static struct imx_i2c_clk_pair vf610_i2c_clk_div[] = {
 151         { 20,   0x00 }, { 22,   0x01 }, { 24,   0x02 }, { 26,   0x03 },
 152         { 28,   0x04 }, { 30,   0x05 }, { 32,   0x09 }, { 34,   0x06 },
 153         { 36,   0x0A }, { 40,   0x07 }, { 44,   0x0C }, { 48,   0x0D },
 154         { 52,   0x43 }, { 56,   0x0E }, { 60,   0x45 }, { 64,   0x12 },
 155         { 68,   0x0F }, { 72,   0x13 }, { 80,   0x14 }, { 88,   0x15 },
 156         { 96,   0x19 }, { 104,  0x16 }, { 112,  0x1A }, { 128,  0x17 },
 157         { 136,  0x4F }, { 144,  0x1C }, { 160,  0x1D }, { 176,  0x55 },
 158         { 192,  0x1E }, { 208,  0x56 }, { 224,  0x22 }, { 228,  0x24 },
 159         { 240,  0x1F }, { 256,  0x23 }, { 288,  0x5C }, { 320,  0x25 },
 160         { 384,  0x26 }, { 448,  0x2A }, { 480,  0x27 }, { 512,  0x2B },
 161         { 576,  0x2C }, { 640,  0x2D }, { 768,  0x31 }, { 896,  0x32 },
 162         { 960,  0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 },
 163         { 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B },
 164         { 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A },
 165         { 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E },
 166 };
 167
 168 enum imx_i2c_type {
 169         IMX1_I2C,
 170         IMX21_I2C,
 171         VF610_I2C,
 172 };
 173
 174 struct imx_i2c_hwdata {
 175         enum imx_i2c_type       devtype;
 176         unsigned                regshift;
 177         struct imx_i2c_clk_pair *clk_div;
 178         unsigned                ndivs;
 179         unsigned                i2sr_clr_opcode;
 180         unsigned                i2cr_ien_opcode;
 181 };
 182
 183 struct imx_i2c_dma {
 184         struct dma_chan         *chan_tx;
 185         struct dma_chan         *chan_rx;
 186         struct dma_chan         *chan_using;
 187         struct completion       cmd_complete;
 188         dma_addr_t              dma_buf;
 189         unsigned int            dma_len;
 190         enum dma_transfer_direction dma_transfer_dir;
 191         enum dma_data_direction dma_data_dir;
 192 };
 193
 194 struct imx_i2c_struct {
 195         struct i2c_adapter      adapter;
 196         struct clk              *clk;
 197         void __iomem            *base;
 198         wait_queue_head_t       queue;
 199         unsigned long           i2csr;
 200         unsigned int            disable_delay;
 201         int                     stopped;
 202         unsigned int            ifdr; /* IMX_I2C_IFDR */
 203         unsigned int            cur_clk;
 204         unsigned int            bitrate;
 205         const struct imx_i2c_hwdata     *hwdata;
 206         struct i2c_bus_recovery_info rinfo;
 207
 208         struct pinctrl *pinctrl;
 209         struct pinctrl_state *pinctrl_pins_default;
 210         struct pinctrl_state *pinctrl_pins_gpio;
 211
 212         struct imx_i2c_dma      *dma;
 213 };
 214
 215 static const struct imx_i2c_hwdata imx1_i2c_hwdata = {
 216         .devtype                = IMX1_I2C,
 217         .regshift               = IMX_I2C_REGSHIFT,
 218         .clk_div                = imx_i2c_clk_div,
 219         .ndivs                  = ARRAY_SIZE(imx_i2c_clk_div),
 220         .i2sr_clr_opcode        = I2SR_CLR_OPCODE_W0C,
 221         .i2cr_ien_opcode        = I2CR_IEN_OPCODE_1,
 222
 223 };
 224
 225 static const struct imx_i2c_hwdata imx21_i2c_hwdata = {
 226         .devtype                = IMX21_I2C,
 227         .regshift               = IMX_I2C_REGSHIFT,
 228         .clk_div                = imx_i2c_clk_div,
 229         .ndivs                  = ARRAY_SIZE(imx_i2c_clk_div),
 230         .i2sr_clr_opcode        = I2SR_CLR_OPCODE_W0C,
 231         .i2cr_ien_opcode        = I2CR_IEN_OPCODE_1,
 232
 233 };
 234
 235 static struct imx_i2c_hwdata vf610_i2c_hwdata = {
 236         .devtype                = VF610_I2C,
 237         .regshift               = VF610_I2C_REGSHIFT,
 238         .clk_div                = vf610_i2c_clk_div,
 239         .ndivs                  = ARRAY_SIZE(vf610_i2c_clk_div),
 240         .i2sr_clr_opcode        = I2SR_CLR_OPCODE_W1C,
 241         .i2cr_ien_opcode        = I2CR_IEN_OPCODE_0,
 242
 243 };
 244
 245 static const struct platform_device_id imx_i2c_devtype[] = {
 246         {
 247                 .name = "imx1-i2c",
 248                 .driver_data = (kernel_ulong_t)&imx1_i2c_hwdata,
 249         }, {
 250                 .name = "imx21-i2c",
 251                 .driver_data = (kernel_ulong_t)&imx21_i2c_hwdata,
 252         }, {
 253                 /* sentinel */
 254         }
 255 };
 256 MODULE_DEVICE_TABLE(platform, imx_i2c_devtype);
 257
 258 static const struct of_device_id i2c_imx_dt_ids[] = {
 259         { .compatible = "fsl,imx1-i2c", .data = &imx1_i2c_hwdata, },
 260         { .compatible = "fsl,imx21-i2c", .data = &imx21_i2c_hwdata, },
 261         { .compatible = "fsl,vf610-i2c", .data = &vf610_i2c_hwdata, },
 262         { /* sentinel */ }
 263 };
 264 MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids);
 265
 266 static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx)
 267 {
 268         return i2c_imx->hwdata->devtype == IMX1_I2C;
 269 }
 270
 271 static inline void imx_i2c_write_reg(unsigned int val,
 272                 struct imx_i2c_struct *i2c_imx, unsigned int reg)
 273 {
 274         writeb(val, i2c_imx->base + (reg << i2c_imx->hwdata->regshift));
 275 }
 276
 277 static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx,
 278                 unsigned int reg)
 279 {
 280         return readb(i2c_imx->base + (reg << i2c_imx->hwdata->regshift));
 281 }
 282
 283 /* Functions for DMA support */
 284 static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
 285                                                 dma_addr_t phy_addr)
 286 {
 287         struct imx_i2c_dma *dma;
 288         struct dma_slave_config dma_sconfig;
 289         struct device *dev = &i2c_imx->adapter.dev;
 290         int ret;
 291
 292         dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
 293         if (!dma)
 294                 return;
 295
 296         dma->chan_tx = dma_request_slave_channel(dev, "tx");
 297         if (!dma->chan_tx) {
 298                 dev_dbg(dev, "can't request DMA tx channel\n");
 299                 goto fail_al;
 300         }
 301
 302         dma_sconfig.dst_addr = phy_addr +
 303                                 (IMX_I2C_I2DR << i2c_imx->hwdata->regshift);
 304         dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 305         dma_sconfig.dst_maxburst = 1;
 306         dma_sconfig.direction = DMA_MEM_TO_DEV;
 307         ret = dmaengine_slave_config(dma->chan_tx, &dma_sconfig);
 308         if (ret < 0) {
 309                 dev_dbg(dev, "can't configure tx channel\n");
 310                 goto fail_tx;
 311         }
 312
 313         dma->chan_rx = dma_request_slave_channel(dev, "rx");
 314         if (!dma->chan_rx) {
 315                 dev_dbg(dev, "can't request DMA rx channel\n");
 316                 goto fail_tx;
 317         }
 318
 319         dma_sconfig.src_addr = phy_addr +
 320                                 (IMX_I2C_I2DR << i2c_imx->hwdata->regshift);
 321         dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 322         dma_sconfig.src_maxburst = 1;
 323         dma_sconfig.direction = DMA_DEV_TO_MEM;
 324         ret = dmaengine_slave_config(dma->chan_rx, &dma_sconfig);
 325         if (ret < 0) {
 326                 dev_dbg(dev, "can't configure rx channel\n");
 327                 goto fail_rx;
 328         }
 329
 330         i2c_imx->dma = dma;
 331         init_completion(&dma->cmd_complete);
 332         dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n",
 333                 dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx));
 334
 335         return;
 336
 337 fail_rx:
 338         dma_release_channel(dma->chan_rx);
 339 fail_tx:
 340         dma_release_channel(dma->chan_tx);
 341 fail_al:
 342         devm_kfree(dev, dma);
 343         dev_info(dev, "can't use DMA, using PIO instead.\n");
 344 }
 345
 346 static void i2c_imx_dma_callback(void *arg)
 347 {
 348         struct imx_i2c_struct *i2c_imx = (struct imx_i2c_struct *)arg;
 349         struct imx_i2c_dma *dma = i2c_imx->dma;
 350
 351         dma_unmap_single(dma->chan_using->device->dev, dma->dma_buf,
 352                         dma->dma_len, dma->dma_data_dir);
 353         complete(&dma->cmd_complete);
 354 }
 355
 356 static int i2c_imx_dma_xfer(struct imx_i2c_struct *i2c_imx,
 357                                         struct i2c_msg *msgs)
 358 {
 359         struct imx_i2c_dma *dma = i2c_imx->dma;
 360         struct dma_async_tx_descriptor *txdesc;
 361         struct device *dev = &i2c_imx->adapter.dev;
 362         struct device *chan_dev = dma->chan_using->device->dev;
 363
 364         dma->dma_buf = dma_map_single(chan_dev, msgs->buf,
 365                                         dma->dma_len, dma->dma_data_dir);
 366         if (dma_mapping_error(chan_dev, dma->dma_buf)) {
 367                 dev_err(dev, "DMA mapping failed\n");
 368                 goto err_map;
 369         }
 370
 371         txdesc = dmaengine_prep_slave_single(dma->chan_using, dma->dma_buf,
 372                                         dma->dma_len, dma->dma_transfer_dir,
 373                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 374         if (!txdesc) {
 375                 dev_err(dev, "Not able to get desc for DMA xfer\n");
 376                 goto err_desc;
 377         }
 378
 379         txdesc->callback = i2c_imx_dma_callback;
 380         txdesc->callback_param = i2c_imx;
 381         if (dma_submit_error(dmaengine_submit(txdesc))) {
 382                 dev_err(dev, "DMA submit failed\n");
 383                 goto err_submit;
 384         }
 385
 386         dma_async_issue_pending(dma->chan_using);
 387         return 0;
 388
 389 err_submit:
 390         dmaengine_terminate_all(dma->chan_using);
 391 err_desc:
 392         dma_unmap_single(chan_dev, dma->dma_buf,
 393                         dma->dma_len, dma->dma_data_dir);
 394 err_map:
 395         return -EINVAL;
 396 }
 397
 398 static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx)
 399 {
 400         struct imx_i2c_dma *dma = i2c_imx->dma;
 401
 402         dma->dma_buf = 0;
 403         dma->dma_len = 0;
 404
 405         dma_release_channel(dma->chan_tx);
 406         dma->chan_tx = NULL;
 407
 408         dma_release_channel(dma->chan_rx);
 409         dma->chan_rx = NULL;
 410
 411         dma->chan_using = NULL;
 412 }
 413
 414 static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
 415 {
 416         unsigned long orig_jiffies = jiffies;
 417         unsigned int temp;
 418
 419         dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
 420
 421         while (1) {
 422                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 423
 424                 /* check for arbitration lost */
 425                 if (temp & I2SR_IAL) {
 426                         temp &= ~I2SR_IAL;
 427                         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
 428                         return -EAGAIN;
 429                 }
 430
 431                 if (for_busy && (temp & I2SR_IBB))
 432                         break;
 433                 if (!for_busy && !(temp & I2SR_IBB))
 434                         break;
 435                 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 436                         dev_dbg(&i2c_imx->adapter.dev,
 437                                 "<%s> I2C bus is busy\n", __func__);
 438                         return -ETIMEDOUT;
 439                 }
 440                 schedule();
 441         }
 442
 443         return 0;
 444 }
 445
 446 static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
 447 {
 448         wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
 449
 450         if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
 451                 dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
 452                 return -ETIMEDOUT;
 453         }
 454         dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
 455         i2c_imx->i2csr = 0;
 456         return 0;
 457 }
 458
 459 static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
 460 {
 461         if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) {
 462                 dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
 463                 return -ENXIO;  /* No ACK */
 464         }
 465
 466         dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
 467         return 0;
 468 }
 469
 470 static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx)
 471 {
 472         struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div;
 473         unsigned int i2c_clk_rate;
 474         unsigned int div;
 475         int i;
 476
 477         /* Divider value calculation */
 478         i2c_clk_rate = clk_get_rate(i2c_imx->clk);
 479         if (i2c_imx->cur_clk == i2c_clk_rate)
 480                 return;
 481
 482         i2c_imx->cur_clk = i2c_clk_rate;
 483
 484         div = (i2c_clk_rate + i2c_imx->bitrate - 1) / i2c_imx->bitrate;
 485         if (div < i2c_clk_div[0].div)
 486                 i = 0;
 487         else if (div > i2c_clk_div[i2c_imx->hwdata->ndivs - 1].div)
 488                 i = i2c_imx->hwdata->ndivs - 1;
 489         else
 490                 for (i = 0; i2c_clk_div[i].div < div; i++)
 491                         ;
 492
 493         /* Store divider value */
 494         i2c_imx->ifdr = i2c_clk_div[i].val;
 495
 496         /*
 497          * There dummy delay is calculated.
 498          * It should be about one I2C clock period long.
 499          * This delay is used in I2C bus disable function
 500          * to fix chip hardware bug.
 501          */
 502         i2c_imx->disable_delay = (500000U * i2c_clk_div[i].div
 503                 + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
 504
 505 #ifdef CONFIG_I2C_DEBUG_BUS
 506         dev_dbg(&i2c_imx->adapter.dev, "I2C_CLK=%d, REQ DIV=%d\n",
 507                 i2c_clk_rate, div);
 508         dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n",
 509                 i2c_clk_div[i].val, i2c_clk_div[i].div);
 510 #endif
 511 }
 512
 513 static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
 514 {
 515         unsigned int temp = 0;
 516         int result;
 517
 518         dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
 519
 520         i2c_imx_set_clk(i2c_imx);
 521
 522         imx_i2c_write_reg(i2c_imx->ifdr, i2c_imx, IMX_I2C_IFDR);
 523         /* Enable I2C controller */
 524         imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR);
 525         imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode, i2c_imx, IMX_I2C_I2CR);
 526
 527         /* Wait controller to be stable */
 528         usleep_range(50, 150);
 529
 530         /* Start I2C transaction */
 531         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 532         temp |= I2CR_MSTA;
 533         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 534         result = i2c_imx_bus_busy(i2c_imx, 1);
 535         if (result)
 536                 return result;
 537         i2c_imx->stopped = 0;
 538
 539         temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
 540         temp &= ~I2CR_DMAEN;
 541         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 542         return result;
 543 }
 544
 545 static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
 546 {
 547         unsigned int temp = 0;
 548
 549         if (!i2c_imx->stopped) {
 550                 /* Stop I2C transaction */
 551                 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
 552                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 553                 temp &= ~(I2CR_MSTA | I2CR_MTX);
 554                 if (i2c_imx->dma)
 555                         temp &= ~I2CR_DMAEN;
 556                 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 557         }
 558         if (is_imx1_i2c(i2c_imx)) {
 559                 /*
 560                  * This delay caused by an i.MXL hardware bug.
 561                  * If no (or too short) delay, no "STOP" bit will be generated.
 562                  */
 563                 udelay(i2c_imx->disable_delay);
 564         }
 565
 566         if (!i2c_imx->stopped) {
 567                 i2c_imx_bus_busy(i2c_imx, 0);
 568                 i2c_imx->stopped = 1;
 569         }
 570
 571         /* Disable I2C controller */
 572         temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
 573         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 574 }
 575
 576 static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
 577 {
 578         struct imx_i2c_struct *i2c_imx = dev_id;
 579         unsigned int temp;
 580
 581         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 582         if (temp & I2SR_IIF) {
 583                 /* save status register */
 584                 i2c_imx->i2csr = temp;
 585                 temp &= ~I2SR_IIF;
 586                 temp |= (i2c_imx->hwdata->i2sr_clr_opcode & I2SR_IIF);
 587                 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
 588                 wake_up(&i2c_imx->queue);
 589                 return IRQ_HANDLED;
 590         }
 591
 592         return IRQ_NONE;
 593 }
 594
 595 static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx,
 596                                         struct i2c_msg *msgs)
 597 {
 598         int result;
 599         unsigned long time_left;
 600         unsigned int temp = 0;
 601         unsigned long orig_jiffies = jiffies;
 602         struct imx_i2c_dma *dma = i2c_imx->dma;
 603         struct device *dev = &i2c_imx->adapter.dev;
 604
 605         dma->chan_using = dma->chan_tx;
 606         dma->dma_transfer_dir = DMA_MEM_TO_DEV;
 607         dma->dma_data_dir = DMA_TO_DEVICE;
 608         dma->dma_len = msgs->len - 1;
 609         result = i2c_imx_dma_xfer(i2c_imx, msgs);
 610         if (result)
 611                 return result;
 612
 613         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 614         temp |= I2CR_DMAEN;
 615         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 616
 617         /*
 618          * Write slave address.
 619          * The first byte must be transmitted by the CPU.
 620          */
 621         imx_i2c_write_reg(msgs->addr << 1, i2c_imx, IMX_I2C_I2DR);
 622         reinit_completion(&i2c_imx->dma->cmd_complete);
 623         time_left = wait_for_completion_timeout(
 624                                 &i2c_imx->dma->cmd_complete,
 625                                 msecs_to_jiffies(DMA_TIMEOUT));
 626         if (time_left == 0) {
 627                 dmaengine_terminate_all(dma->chan_using);
 628                 return -ETIMEDOUT;
 629         }
 630
 631         /* Waiting for transfer complete. */
 632         while (1) {
 633                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 634                 if (temp & I2SR_ICF)
 635                         break;
 636                 if (time_after(jiffies, orig_jiffies +
 637                                 msecs_to_jiffies(DMA_TIMEOUT))) {
 638                         dev_dbg(dev, "<%s> Timeout\n", __func__);
 639                         return -ETIMEDOUT;
 640                 }
 641                 schedule();
 642         }
 643
 644         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 645         temp &= ~I2CR_DMAEN;
 646         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 647
 648         /* The last data byte must be transferred by the CPU. */
 649         imx_i2c_write_reg(msgs->buf[msgs->len-1],
 650                                 i2c_imx, IMX_I2C_I2DR);
 651         result = i2c_imx_trx_complete(i2c_imx);
 652         if (result)
 653                 return result;
 654
 655         return i2c_imx_acked(i2c_imx);
 656 }
 657
 658 static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx,
 659                         struct i2c_msg *msgs, bool is_lastmsg)
 660 {
 661         int result;
 662         unsigned long time_left;
 663         unsigned int temp;
 664         unsigned long orig_jiffies = jiffies;
 665         struct imx_i2c_dma *dma = i2c_imx->dma;
 666         struct device *dev = &i2c_imx->adapter.dev;
 667
 668         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 669         temp |= I2CR_DMAEN;
 670         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 671
 672         dma->chan_using = dma->chan_rx;
 673         dma->dma_transfer_dir = DMA_DEV_TO_MEM;
 674         dma->dma_data_dir = DMA_FROM_DEVICE;
 675         /* The last two data bytes must be transferred by the CPU. */
 676         dma->dma_len = msgs->len - 2;
 677         result = i2c_imx_dma_xfer(i2c_imx, msgs);
 678         if (result)
 679                 return result;
 680
 681         reinit_completion(&i2c_imx->dma->cmd_complete);
 682         time_left = wait_for_completion_timeout(
 683                                 &i2c_imx->dma->cmd_complete,
 684                                 msecs_to_jiffies(DMA_TIMEOUT));
 685         if (time_left == 0) {
 686                 dmaengine_terminate_all(dma->chan_using);
 687                 return -ETIMEDOUT;
 688         }
 689
 690         /* waiting for transfer complete. */
 691         while (1) {
 692                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 693                 if (temp & I2SR_ICF)
 694                         break;
 695                 if (time_after(jiffies, orig_jiffies +
 696                                 msecs_to_jiffies(DMA_TIMEOUT))) {
 697                         dev_dbg(dev, "<%s> Timeout\n", __func__);
 698                         return -ETIMEDOUT;
 699                 }
 700                 schedule();
 701         }
 702
 703         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 704         temp &= ~I2CR_DMAEN;
 705         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 706
 707         /* read n-1 byte data */
 708         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 709         temp |= I2CR_TXAK;
 710         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 711
 712         msgs->buf[msgs->len-2] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
 713         /* read n byte data */
 714         result = i2c_imx_trx_complete(i2c_imx);
 715         if (result)
 716                 return result;
 717
 718         if (is_lastmsg) {
 719                 /*
 720                  * It must generate STOP before read I2DR to prevent
 721                  * controller from generating another clock cycle
 722                  */
 723                 dev_dbg(dev, "<%s> clear MSTA\n", __func__);
 724                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 725                 temp &= ~(I2CR_MSTA | I2CR_MTX);
 726                 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 727                 i2c_imx_bus_busy(i2c_imx, 0);
 728                 i2c_imx->stopped = 1;
 729         } else {
 730                 /*
 731                  * For i2c master receiver repeat restart operation like:
 732                  * read -> repeat MSTA -> read/write
 733                  * The controller must set MTX before read the last byte in
 734                  * the first read operation, otherwise the first read cost
 735                  * one extra clock cycle.
 736                  */
 737                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 738                 temp |= I2CR_MTX;
 739                 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 740         }
 741         msgs->buf[msgs->len-1] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
 742
 743         return 0;
 744 }
 745
 746 static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
 747 {
 748         int i, result;
 749
 750         dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
 751                 __func__, msgs->addr << 1);
 752
 753         /* write slave address */
 754         imx_i2c_write_reg(msgs->addr << 1, i2c_imx, IMX_I2C_I2DR);
 755         result = i2c_imx_trx_complete(i2c_imx);
 756         if (result)
 757                 return result;
 758         result = i2c_imx_acked(i2c_imx);
 759         if (result)
 760                 return result;
 761         dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__);
 762
 763         /* write data */
 764         for (i = 0; i < msgs->len; i++) {
 765                 dev_dbg(&i2c_imx->adapter.dev,
 766                         "<%s> write byte: B%d=0x%X\n",
 767                         __func__, i, msgs->buf[i]);
 768                 imx_i2c_write_reg(msgs->buf[i], i2c_imx, IMX_I2C_I2DR);
 769                 result = i2c_imx_trx_complete(i2c_imx);
 770                 if (result)
 771                         return result;
 772                 result = i2c_imx_acked(i2c_imx);
 773                 if (result)
 774                         return result;
 775         }
 776         return 0;
 777 }
 778
 779 static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, bool is_lastmsg)
 780 {
 781         int i, result;
 782         unsigned int temp;
 783         int block_data = msgs->flags & I2C_M_RECV_LEN;
 784
 785         dev_dbg(&i2c_imx->adapter.dev,
 786                 "<%s> write slave address: addr=0x%x\n",
 787                 __func__, (msgs->addr << 1) | 0x01);
 788
 789         /* write slave address */
 790         imx_i2c_write_reg((msgs->addr << 1) | 0x01, i2c_imx, IMX_I2C_I2DR);
 791         result = i2c_imx_trx_complete(i2c_imx);
 792         if (result)
 793                 return result;
 794         result = i2c_imx_acked(i2c_imx);
 795         if (result)
 796                 return result;
 797
 798         dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
 799
 800         /* setup bus to read data */
 801         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 802         temp &= ~I2CR_MTX;
 803
 804         /*
 805          * Reset the I2CR_TXAK flag initially for SMBus block read since the
 806          * length is unknown
 807          */
 808         if ((msgs->len - 1) || block_data)
 809                 temp &= ~I2CR_TXAK;
 810         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 811         imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */
 812
 813         dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
 814
 815         if (i2c_imx->dma && msgs->len >= DMA_THRESHOLD && !block_data)
 816                 return i2c_imx_dma_read(i2c_imx, msgs, is_lastmsg);
 817
 818         /* read data */
 819         for (i = 0; i < msgs->len; i++) {
 820                 u8 len = 0;
 821
 822                 result = i2c_imx_trx_complete(i2c_imx);
 823                 if (result)
 824                         return result;
 825                 /*
 826                  * First byte is the length of remaining packet
 827                  * in the SMBus block data read. Add it to
 828                  * msgs->len.
 829                  */
 830                 if ((!i) && block_data) {
 831                         len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
 832                         if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX))
 833                                 return -EPROTO;
 834                         dev_dbg(&i2c_imx->adapter.dev,
 835                                 "<%s> read length: 0x%X\n",
 836                                 __func__, len);
 837                         msgs->len += len;
 838                 }
 839                 if (i == (msgs->len - 1)) {
 840                         if (is_lastmsg) {
 841                                 /*
 842                                  * It must generate STOP before read I2DR to prevent
 843                                  * controller from generating another clock cycle
 844                                  */
 845                                 dev_dbg(&i2c_imx->adapter.dev,
 846                                         "<%s> clear MSTA\n", __func__);
 847                                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 848                                 temp &= ~(I2CR_MSTA | I2CR_MTX);
 849                                 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 850                                 i2c_imx_bus_busy(i2c_imx, 0);
 851                                 i2c_imx->stopped = 1;
 852                         } else {
 853                                 /*
 854                                  * For i2c master receiver repeat restart operation like:
 855                                  * read -> repeat MSTA -> read/write
 856                                  * The controller must set MTX before read the last byte in
 857                                  * the first read operation, otherwise the first read cost
 858                                  * one extra clock cycle.
 859                                  */
 860                                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 861                                 temp |= I2CR_MTX;
 862                                 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 863                         }
 864                 } else if (i == (msgs->len - 2)) {
 865                         dev_dbg(&i2c_imx->adapter.dev,
 866                                 "<%s> set TXAK\n", __func__);
 867                         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 868                         temp |= I2CR_TXAK;
 869                         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 870                 }
 871                 if ((!i) && block_data)
 872                         msgs->buf[0] = len;
 873                 else
 874                         msgs->buf[i] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
 875                 dev_dbg(&i2c_imx->adapter.dev,
 876                         "<%s> read byte: B%d=0x%X\n",
 877                         __func__, i, msgs->buf[i]);
 878         }
 879         return 0;
 880 }
 881
 882 static int i2c_imx_xfer(struct i2c_adapter *adapter,
 883                                                 struct i2c_msg *msgs, int num)
 884 {
 885         unsigned int i, temp;
 886         int result;
 887         bool is_lastmsg = false;
 888         struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
 889
 890         dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
 891
 892         result = pm_runtime_get_sync(i2c_imx->adapter.dev.parent);
 893         if (result < 0)
 894                 goto out;
 895
 896         /* Start I2C transfer */
 897         result = i2c_imx_start(i2c_imx);
 898         if (result) {
 899                 if (i2c_imx->adapter.bus_recovery_info) {
 900                         i2c_recover_bus(&i2c_imx->adapter);
 901                         result = i2c_imx_start(i2c_imx);
 902                 }
 903         }
 904
 905         if (result)
 906                 goto fail0;
 907
 908         /* read/write data */
 909         for (i = 0; i < num; i++) {
 910                 if (i == num - 1)
 911                         is_lastmsg = true;
 912
 913                 if (i) {
 914                         dev_dbg(&i2c_imx->adapter.dev,
 915                                 "<%s> repeated start\n", __func__);
 916                         temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 917                         temp |= I2CR_RSTA;
 918                         imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 919                         result = i2c_imx_bus_busy(i2c_imx, 1);
 920                         if (result)
 921                                 goto fail0;
 922                 }
 923                 dev_dbg(&i2c_imx->adapter.dev,
 924                         "<%s> transfer message: %d\n", __func__, i);
 925                 /* write/read data */
 926 #ifdef CONFIG_I2C_DEBUG_BUS
 927                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 928                 dev_dbg(&i2c_imx->adapter.dev,
 929                         "<%s> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n",
 930                         __func__,
 931                         (temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
 932                         (temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
 933                         (temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
 934                 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 935                 dev_dbg(&i2c_imx->adapter.dev,
 936                         "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n",
 937                         __func__,
 938                         (temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0),
 939                         (temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0),
 940                         (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0),
 941                         (temp & I2SR_RXAK ? 1 : 0));
 942 #endif
 943                 if (msgs[i].flags & I2C_M_RD)
 944                         result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg);
 945                 else {
 946                         if (i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD)
 947                                 result = i2c_imx_dma_write(i2c_imx, &msgs[i]);
 948                         else
 949                                 result = i2c_imx_write(i2c_imx, &msgs[i]);
 950                 }
 951                 if (result)
 952                         goto fail0;
 953         }
 954
 955 fail0:
 956         /* Stop I2C transfer */
 957         i2c_imx_stop(i2c_imx);
 958
 959         pm_runtime_mark_last_busy(i2c_imx->adapter.dev.parent);
 960         pm_runtime_put_autosuspend(i2c_imx->adapter.dev.parent);
 961
 962 out:
 963         dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
 964                 (result < 0) ? "error" : "success msg",
 965                         (result < 0) ? result : num);
 966         return (result < 0) ? result : num;
 967 }
 968
 969 static void i2c_imx_prepare_recovery(struct i2c_adapter *adap)
 970 {
 971         struct imx_i2c_struct *i2c_imx;
 972
 973         i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
 974
 975         pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_gpio);
 976 }
 977
 978 static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap)
 979 {
 980         struct imx_i2c_struct *i2c_imx;
 981
 982         i2c_imx = container_of(adap, struct imx_i2c_struct, adapter);
 983
 984         pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default);
 985 }
 986
 987 /*
 988  * We switch SCL and SDA to their GPIO function and do some bitbanging
 989  * for bus recovery. These alternative pinmux settings can be
 990  * described in the device tree by a separate pinctrl state "gpio". If
 991  * this is missing this is not a big problem, the only implication is
 992  * that we can't do bus recovery.
 993  */
 994 static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
 995                 struct platform_device *pdev)
 996 {
 997         struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
 998
 999         i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
1000         if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
1001                 dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n");
1002                 return PTR_ERR(i2c_imx->pinctrl);
1003         }
1004
1005         i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl,
1006                         PINCTRL_STATE_DEFAULT);
1007         i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl,
1008                         "gpio");
1009         rinfo->sda_gpio = of_get_named_gpio(pdev->dev.of_node, "sda-gpios", 0);
1010         rinfo->scl_gpio = of_get_named_gpio(pdev->dev.of_node, "scl-gpios", 0);
1011
1012         if (rinfo->sda_gpio == -EPROBE_DEFER ||
1013             rinfo->scl_gpio == -EPROBE_DEFER) {
1014                 return -EPROBE_DEFER;
1015         } else if (!gpio_is_valid(rinfo->sda_gpio) ||
1016                    !gpio_is_valid(rinfo->scl_gpio) ||
1017                    IS_ERR(i2c_imx->pinctrl_pins_default) ||
1018                    IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
1019                 dev_dbg(&pdev->dev, "recovery information incomplete\n");
1020                 return 0;
1021         }
1022
1023         dev_dbg(&pdev->dev, "using scl-gpio %d and sda-gpio %d for recovery\n",
1024                         rinfo->sda_gpio, rinfo->scl_gpio);
1025
1026         rinfo->prepare_recovery = i2c_imx_prepare_recovery;
1027         rinfo->unprepare_recovery = i2c_imx_unprepare_recovery;
1028         rinfo->recover_bus = i2c_generic_gpio_recovery;
1029         i2c_imx->adapter.bus_recovery_info = rinfo;
1030
1031         return 0;
1032 }
1033
1034 static u32 i2c_imx_func(struct i2c_adapter *adapter)
1035 {
1036         return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
1037                 | I2C_FUNC_SMBUS_READ_BLOCK_DATA;
1038 }
1039
1040 static const struct i2c_algorithm i2c_imx_algo = {
1041         .master_xfer    = i2c_imx_xfer,
1042         .functionality  = i2c_imx_func,
1043 };
1044
1045 static int i2c_imx_probe(struct platform_device *pdev)
1046 {
1047         const struct of_device_id *of_id = of_match_device(i2c_imx_dt_ids,
1048                                                            &pdev->dev);
1049         struct imx_i2c_struct *i2c_imx;
1050         struct resource *res;
1051         struct imxi2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
1052         void __iomem *base;
1053         int irq, ret;
1054         dma_addr_t phy_addr;
1055
1056         dev_dbg(&pdev->dev, "<%s>\n", __func__);
1057
1058         irq = platform_get_irq(pdev, 0);
1059         if (irq < 0) {
1060                 dev_err(&pdev->dev, "can't get irq number\n");
1061                 return irq;
1062         }
1063
1064         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1065         base = devm_ioremap_resource(&pdev->dev, res);
1066         if (IS_ERR(base))
1067                 return PTR_ERR(base);
1068
1069         phy_addr = (dma_addr_t)res->start;
1070         i2c_imx = devm_kzalloc(&pdev->dev, sizeof(*i2c_imx), GFP_KERNEL);
1071         if (!i2c_imx)
1072                 return -ENOMEM;
1073
1074         if (of_id)
1075                 i2c_imx->hwdata = of_id->data;
1076         else
1077                 i2c_imx->hwdata = (struct imx_i2c_hwdata *)
1078                                 platform_get_device_id(pdev)->driver_data;
1079
1080         /* Setup i2c_imx driver structure */
1081         strlcpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name));
1082         i2c_imx->adapter.owner          = THIS_MODULE;
1083         i2c_imx->adapter.algo           = &i2c_imx_algo;
1084         i2c_imx->adapter.dev.parent     = &pdev->dev;
1085         i2c_imx->adapter.nr             = pdev->id;
1086         i2c_imx->adapter.dev.of_node    = pdev->dev.of_node;
1087         i2c_imx->base                   = base;
1088
1089         /* Get I2C clock */
1090         i2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
1091         if (IS_ERR(i2c_imx->clk)) {
1092                 dev_err(&pdev->dev, "can't get I2C clock\n");
1093                 return PTR_ERR(i2c_imx->clk);
1094         }
1095
1096         ret = clk_prepare_enable(i2c_imx->clk);
1097         if (ret) {
1098                 dev_err(&pdev->dev, "can't enable I2C clock, ret=%d\n", ret);
1099                 return ret;
1100         }
1101
1102         /* Request IRQ */
1103         ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0,
1104                                 pdev->name, i2c_imx);
1105         if (ret) {
1106                 dev_err(&pdev->dev, "can't claim irq %d\n", irq);
1107                 goto clk_disable;
1108         }
1109
1110         /* Init queue */
1111         init_waitqueue_head(&i2c_imx->queue);
1112
1113         /* Set up adapter data */
1114         i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
1115
1116         /* Set up platform driver data */
1117         platform_set_drvdata(pdev, i2c_imx);
1118
1119         pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT);
1120         pm_runtime_use_autosuspend(&pdev->dev);
1121         pm_runtime_set_active(&pdev->dev);
1122         pm_runtime_enable(&pdev->dev);
1123
1124         ret = pm_runtime_get_sync(&pdev->dev);
1125         if (ret < 0)
1126                 goto rpm_disable;
1127
1128         /* Set up clock divider */
1129         i2c_imx->bitrate = IMX_I2C_BIT_RATE;
1130         ret = of_property_read_u32(pdev->dev.of_node,
1131                                    "clock-frequency", &i2c_imx->bitrate);
1132         if (ret < 0 && pdata && pdata->bitrate)
1133                 i2c_imx->bitrate = pdata->bitrate;
1134
1135         /* Set up chip registers to defaults */
1136         imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
1137                         i2c_imx, IMX_I2C_I2CR);
1138         imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR);
1139
1140         /* Init optional bus recovery function */
1141         ret = i2c_imx_init_recovery_info(i2c_imx, pdev);
1142         /* Give it another chance if pinctrl used is not ready yet */
1143         if (ret == -EPROBE_DEFER)
1144                 goto rpm_disable;
1145
1146         /* Add I2C adapter */
1147         ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
1148         if (ret < 0)
1149                 goto rpm_disable;
1150
1151         pm_runtime_mark_last_busy(&pdev->dev);
1152         pm_runtime_put_autosuspend(&pdev->dev);
1153
1154         dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq);
1155         dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res);
1156         dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
1157                 i2c_imx->adapter.name);
1158         dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
1159
1160         /* Init DMA config if supported */
1161         i2c_imx_dma_request(i2c_imx, phy_addr);
1162
1163         return 0;   /* Return OK */
1164
1165 rpm_disable:
1166         pm_runtime_put_noidle(&pdev->dev);
1167         pm_runtime_disable(&pdev->dev);
1168         pm_runtime_set_suspended(&pdev->dev);
1169         pm_runtime_dont_use_autosuspend(&pdev->dev);
1170
1171 clk_disable:
1172         clk_disable_unprepare(i2c_imx->clk);
1173         return ret;
1174 }
1175
1176 static int i2c_imx_remove(struct platform_device *pdev)
1177 {
1178         struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
1179         int ret;
1180
1181         ret = pm_runtime_get_sync(&pdev->dev);
1182         if (ret < 0)
1183                 return ret;
1184
1185         /* remove adapter */
1186         dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
1187         i2c_del_adapter(&i2c_imx->adapter);
1188
1189         if (i2c_imx->dma)
1190                 i2c_imx_dma_free(i2c_imx);
1191
1192         /* setup chip registers to defaults */
1193         imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR);
1194         imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR);
1195         imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR);
1196         imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
1197
1198         clk_disable_unprepare(i2c_imx->clk);
1199
1200         pm_runtime_put_noidle(&pdev->dev);
1201         pm_runtime_disable(&pdev->dev);
1202
1203         return 0;
1204 }
1205
1206 #ifdef CONFIG_PM
1207 static int i2c_imx_runtime_suspend(struct device *dev)
1208 {
1209         struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
1210
1211         clk_disable_unprepare(i2c_imx->clk);
1212
1213         return 0;
1214 }
1215
1216 static int i2c_imx_runtime_resume(struct device *dev)
1217 {
1218         struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev);
1219         int ret;
1220
1221         ret = clk_prepare_enable(i2c_imx->clk);
1222         if (ret)
1223                 dev_err(dev, "can't enable I2C clock, ret=%d\n", ret);
1224
1225         return ret;
1226 }
1227
1228 static const struct dev_pm_ops i2c_imx_pm_ops = {
1229         SET_RUNTIME_PM_OPS(i2c_imx_runtime_suspend,
1230                            i2c_imx_runtime_resume, NULL)
1231 };
1232 #define I2C_IMX_PM_OPS (&i2c_imx_pm_ops)
1233 #else
1234 #define I2C_IMX_PM_OPS NULL
1235 #endif /* CONFIG_PM */
1236
1237 static struct platform_driver i2c_imx_driver = {
1238         .probe = i2c_imx_probe,
1239         .remove = i2c_imx_remove,
1240         .driver = {
1241                 .name = DRIVER_NAME,
1242                 .pm = I2C_IMX_PM_OPS,
1243                 .of_match_table = i2c_imx_dt_ids,
1244         },
1245         .id_table = imx_i2c_devtype,
1246 };
1247
1248 static int __init i2c_adap_imx_init(void)
1249 {
1250         return platform_driver_register(&i2c_imx_driver);
1251 }
1252 subsys_initcall(i2c_adap_imx_init);
1253
1254 static void __exit i2c_adap_imx_exit(void)
1255 {
1256         platform_driver_unregister(&i2c_imx_driver);
1257 }
1258 module_exit(i2c_adap_imx_exit);
1259
1260 MODULE_LICENSE("GPL");
1261 MODULE_AUTHOR("Darius Augulis");
1262 MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
1263 MODULE_ALIAS("platform:" DRIVER_NAME);