drivers/i2c/busses/i2c-omap.c

   1 /*
   2  * TI OMAP I2C master mode driver
   3  *
   4  * Copyright (C) 2003 MontaVista Software, Inc.
   5  * Copyright (C) 2005 Nokia Corporation
   6  * Copyright (C) 2004 - 2007 Texas Instruments.
   7  *
   8  * Originally written by MontaVista Software, Inc.
   9  * Additional contributions by:
  10  *      Tony Lindgren <tony@atomide.com>
  11  *      Imre Deak <imre.deak@nokia.com>
  12  *      Juha Yrjölä <juha.yrjola@solidboot.com>
  13  *      Syed Khasim <x0khasim@ti.com>
  14  *      Nishant Menon <nm@ti.com>
  15  *
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License as published by
  18  * the Free Software Foundation; either version 2 of the License, or
  19  * (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful,
  22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  24  * GNU General Public License for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  29  */
  30
  31 #include <linux/module.h>
  32 #include <linux/delay.h>
  33 #include <linux/i2c.h>
  34 #include <linux/err.h>
  35 #include <linux/interrupt.h>
  36 #include <linux/completion.h>
  37 #include <linux/platform_device.h>
  38 #include <linux/clk.h>
  39 #include <linux/io.h>
  40 #include <linux/of.h>
  41 #include <linux/of_i2c.h>
  42 #include <linux/of_device.h>
  43 #include <linux/slab.h>
  44 #include <linux/i2c-omap.h>
  45 #include <linux/pm_runtime.h>
  46
  47 /* I2C controller revisions */
  48 #define OMAP_I2C_OMAP1_REV_2            0x20
  49
  50 /* I2C controller revisions present on specific hardware */
  51 #define OMAP_I2C_REV_ON_2430            0x36
  52 #define OMAP_I2C_REV_ON_3430_3530       0x3C
  53 #define OMAP_I2C_REV_ON_3630_4430       0x40
  54
  55 /* timeout waiting for the controller to respond */
  56 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
  57
  58 /* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
  59 enum {
  60         OMAP_I2C_REV_REG = 0,
  61         OMAP_I2C_IE_REG,
  62         OMAP_I2C_STAT_REG,
  63         OMAP_I2C_IV_REG,
  64         OMAP_I2C_WE_REG,
  65         OMAP_I2C_SYSS_REG,
  66         OMAP_I2C_BUF_REG,
  67         OMAP_I2C_CNT_REG,
  68         OMAP_I2C_DATA_REG,
  69         OMAP_I2C_SYSC_REG,
  70         OMAP_I2C_CON_REG,
  71         OMAP_I2C_OA_REG,
  72         OMAP_I2C_SA_REG,
  73         OMAP_I2C_PSC_REG,
  74         OMAP_I2C_SCLL_REG,
  75         OMAP_I2C_SCLH_REG,
  76         OMAP_I2C_SYSTEST_REG,
  77         OMAP_I2C_BUFSTAT_REG,
  78         /* only on OMAP4430 */
  79         OMAP_I2C_IP_V2_REVNB_LO,
  80         OMAP_I2C_IP_V2_REVNB_HI,
  81         OMAP_I2C_IP_V2_IRQSTATUS_RAW,
  82         OMAP_I2C_IP_V2_IRQENABLE_SET,
  83         OMAP_I2C_IP_V2_IRQENABLE_CLR,
  84 };
  85
  86 /* I2C Interrupt Enable Register (OMAP_I2C_IE): */
  87 #define OMAP_I2C_IE_XDR         (1 << 14)       /* TX Buffer drain int enable */
  88 #define OMAP_I2C_IE_RDR         (1 << 13)       /* RX Buffer drain int enable */
  89 #define OMAP_I2C_IE_XRDY        (1 << 4)        /* TX data ready int enable */
  90 #define OMAP_I2C_IE_RRDY        (1 << 3)        /* RX data ready int enable */
  91 #define OMAP_I2C_IE_ARDY        (1 << 2)        /* Access ready int enable */
  92 #define OMAP_I2C_IE_NACK        (1 << 1)        /* No ack interrupt enable */
  93 #define OMAP_I2C_IE_AL          (1 << 0)        /* Arbitration lost int ena */
  94
  95 /* I2C Status Register (OMAP_I2C_STAT): */
  96 #define OMAP_I2C_STAT_XDR       (1 << 14)       /* TX Buffer draining */
  97 #define OMAP_I2C_STAT_RDR       (1 << 13)       /* RX Buffer draining */
  98 #define OMAP_I2C_STAT_BB        (1 << 12)       /* Bus busy */
  99 #define OMAP_I2C_STAT_ROVR      (1 << 11)       /* Receive overrun */
 100 #define OMAP_I2C_STAT_XUDF      (1 << 10)       /* Transmit underflow */
 101 #define OMAP_I2C_STAT_AAS       (1 << 9)        /* Address as slave */
 102 #define OMAP_I2C_STAT_AD0       (1 << 8)        /* Address zero */
 103 #define OMAP_I2C_STAT_XRDY      (1 << 4)        /* Transmit data ready */
 104 #define OMAP_I2C_STAT_RRDY      (1 << 3)        /* Receive data ready */
 105 #define OMAP_I2C_STAT_ARDY      (1 << 2)        /* Register access ready */
 106 #define OMAP_I2C_STAT_NACK      (1 << 1)        /* No ack interrupt enable */
 107 #define OMAP_I2C_STAT_AL        (1 << 0)        /* Arbitration lost int ena */
 108
 109 /* I2C WE wakeup enable register */
 110 #define OMAP_I2C_WE_XDR_WE      (1 << 14)       /* TX drain wakup */
 111 #define OMAP_I2C_WE_RDR_WE      (1 << 13)       /* RX drain wakeup */
 112 #define OMAP_I2C_WE_AAS_WE      (1 << 9)        /* Address as slave wakeup*/
 113 #define OMAP_I2C_WE_BF_WE       (1 << 8)        /* Bus free wakeup */
 114 #define OMAP_I2C_WE_STC_WE      (1 << 6)        /* Start condition wakeup */
 115 #define OMAP_I2C_WE_GC_WE       (1 << 5)        /* General call wakeup */
 116 #define OMAP_I2C_WE_DRDY_WE     (1 << 3)        /* TX/RX data ready wakeup */
 117 #define OMAP_I2C_WE_ARDY_WE     (1 << 2)        /* Reg access ready wakeup */
 118 #define OMAP_I2C_WE_NACK_WE     (1 << 1)        /* No acknowledgment wakeup */
 119 #define OMAP_I2C_WE_AL_WE       (1 << 0)        /* Arbitration lost wakeup */
 120
 121 #define OMAP_I2C_WE_ALL         (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
 122                                 OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
 123                                 OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
 124                                 OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
 125                                 OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
 126
 127 /* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
 128 #define OMAP_I2C_BUF_RDMA_EN    (1 << 15)       /* RX DMA channel enable */
 129 #define OMAP_I2C_BUF_RXFIF_CLR  (1 << 14)       /* RX FIFO Clear */
 130 #define OMAP_I2C_BUF_XDMA_EN    (1 << 7)        /* TX DMA channel enable */
 131 #define OMAP_I2C_BUF_TXFIF_CLR  (1 << 6)        /* TX FIFO Clear */
 132
 133 /* I2C Configuration Register (OMAP_I2C_CON): */
 134 #define OMAP_I2C_CON_EN         (1 << 15)       /* I2C module enable */
 135 #define OMAP_I2C_CON_BE         (1 << 14)       /* Big endian mode */
 136 #define OMAP_I2C_CON_OPMODE_HS  (1 << 12)       /* High Speed support */
 137 #define OMAP_I2C_CON_STB        (1 << 11)       /* Start byte mode (master) */
 138 #define OMAP_I2C_CON_MST        (1 << 10)       /* Master/slave mode */
 139 #define OMAP_I2C_CON_TRX        (1 << 9)        /* TX/RX mode (master only) */
 140 #define OMAP_I2C_CON_XA         (1 << 8)        /* Expand address */
 141 #define OMAP_I2C_CON_RM         (1 << 2)        /* Repeat mode (master only) */
 142 #define OMAP_I2C_CON_STP        (1 << 1)        /* Stop cond (master only) */
 143 #define OMAP_I2C_CON_STT        (1 << 0)        /* Start condition (master) */
 144
 145 /* I2C SCL time value when Master */
 146 #define OMAP_I2C_SCLL_HSSCLL    8
 147 #define OMAP_I2C_SCLH_HSSCLH    8
 148
 149 /* I2C System Test Register (OMAP_I2C_SYSTEST): */
 150 #ifdef DEBUG
 151 #define OMAP_I2C_SYSTEST_ST_EN          (1 << 15)       /* System test enable */
 152 #define OMAP_I2C_SYSTEST_FREE           (1 << 14)       /* Free running mode */
 153 #define OMAP_I2C_SYSTEST_TMODE_MASK     (3 << 12)       /* Test mode select */
 154 #define OMAP_I2C_SYSTEST_TMODE_SHIFT    (12)            /* Test mode select */
 155 #define OMAP_I2C_SYSTEST_SCL_I          (1 << 3)        /* SCL line sense in */
 156 #define OMAP_I2C_SYSTEST_SCL_O          (1 << 2)        /* SCL line drive out */
 157 #define OMAP_I2C_SYSTEST_SDA_I          (1 << 1)        /* SDA line sense in */
 158 #define OMAP_I2C_SYSTEST_SDA_O          (1 << 0)        /* SDA line drive out */
 159 #endif
 160
 161 /* OCP_SYSSTATUS bit definitions */
 162 #define SYSS_RESETDONE_MASK             (1 << 0)
 163
 164 /* OCP_SYSCONFIG bit definitions */
 165 #define SYSC_CLOCKACTIVITY_MASK         (0x3 << 8)
 166 #define SYSC_SIDLEMODE_MASK             (0x3 << 3)
 167 #define SYSC_ENAWAKEUP_MASK             (1 << 2)
 168 #define SYSC_SOFTRESET_MASK             (1 << 1)
 169 #define SYSC_AUTOIDLE_MASK              (1 << 0)
 170
 171 #define SYSC_IDLEMODE_SMART             0x2
 172 #define SYSC_CLOCKACTIVITY_FCLK         0x2
 173
 174 /* Errata definitions */
 175 #define I2C_OMAP_ERRATA_I207            (1 << 0)
 176 #define I2C_OMAP_ERRATA_I462            (1 << 1)
 177
 178 struct omap_i2c_dev {
 179         struct device           *dev;
 180         void __iomem            *base;          /* virtual */
 181         int                     irq;
 182         int                     reg_shift;      /* bit shift for I2C register addresses */
 183         struct completion       cmd_complete;
 184         struct resource         *ioarea;
 185         u32                     latency;        /* maximum mpu wkup latency */
 186         void                    (*set_mpu_wkup_lat)(struct device *dev,
 187                                                     long latency);
 188         u32                     speed;          /* Speed of bus in kHz */
 189         u32                     dtrev;          /* extra revision from DT */
 190         u32                     flags;
 191         u16                     cmd_err;
 192         u8                      *buf;
 193         u8                      *regs;
 194         size_t                  buf_len;
 195         struct i2c_adapter      adapter;
 196         u8                      fifo_size;      /* use as flag and value
 197                                                  * fifo_size==0 implies no fifo
 198                                                  * if set, should be trsh+1
 199                                                  */
 200         u8                      rev;
 201         unsigned                b_hw:1;         /* bad h/w fixes */
 202         u16                     iestate;        /* Saved interrupt register */
 203         u16                     pscstate;
 204         u16                     scllstate;
 205         u16                     sclhstate;
 206         u16                     bufstate;
 207         u16                     syscstate;
 208         u16                     westate;
 209         u16                     errata;
 210 };
 211
 212 static const u8 reg_map_ip_v1[] = {
 213         [OMAP_I2C_REV_REG] = 0x00,
 214         [OMAP_I2C_IE_REG] = 0x01,
 215         [OMAP_I2C_STAT_REG] = 0x02,
 216         [OMAP_I2C_IV_REG] = 0x03,
 217         [OMAP_I2C_WE_REG] = 0x03,
 218         [OMAP_I2C_SYSS_REG] = 0x04,
 219         [OMAP_I2C_BUF_REG] = 0x05,
 220         [OMAP_I2C_CNT_REG] = 0x06,
 221         [OMAP_I2C_DATA_REG] = 0x07,
 222         [OMAP_I2C_SYSC_REG] = 0x08,
 223         [OMAP_I2C_CON_REG] = 0x09,
 224         [OMAP_I2C_OA_REG] = 0x0a,
 225         [OMAP_I2C_SA_REG] = 0x0b,
 226         [OMAP_I2C_PSC_REG] = 0x0c,
 227         [OMAP_I2C_SCLL_REG] = 0x0d,
 228         [OMAP_I2C_SCLH_REG] = 0x0e,
 229         [OMAP_I2C_SYSTEST_REG] = 0x0f,
 230         [OMAP_I2C_BUFSTAT_REG] = 0x10,
 231 };
 232
 233 static const u8 reg_map_ip_v2[] = {
 234         [OMAP_I2C_REV_REG] = 0x04,
 235         [OMAP_I2C_IE_REG] = 0x2c,
 236         [OMAP_I2C_STAT_REG] = 0x28,
 237         [OMAP_I2C_IV_REG] = 0x34,
 238         [OMAP_I2C_WE_REG] = 0x34,
 239         [OMAP_I2C_SYSS_REG] = 0x90,
 240         [OMAP_I2C_BUF_REG] = 0x94,
 241         [OMAP_I2C_CNT_REG] = 0x98,
 242         [OMAP_I2C_DATA_REG] = 0x9c,
 243         [OMAP_I2C_SYSC_REG] = 0x10,
 244         [OMAP_I2C_CON_REG] = 0xa4,
 245         [OMAP_I2C_OA_REG] = 0xa8,
 246         [OMAP_I2C_SA_REG] = 0xac,
 247         [OMAP_I2C_PSC_REG] = 0xb0,
 248         [OMAP_I2C_SCLL_REG] = 0xb4,
 249         [OMAP_I2C_SCLH_REG] = 0xb8,
 250         [OMAP_I2C_SYSTEST_REG] = 0xbC,
 251         [OMAP_I2C_BUFSTAT_REG] = 0xc0,
 252         [OMAP_I2C_IP_V2_REVNB_LO] = 0x00,
 253         [OMAP_I2C_IP_V2_REVNB_HI] = 0x04,
 254         [OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24,
 255         [OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c,
 256         [OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
 257 };
 258
 259 static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
 260                                       int reg, u16 val)
 261 {
 262         __raw_writew(val, i2c_dev->base +
 263                         (i2c_dev->regs[reg] << i2c_dev->reg_shift));
 264 }
 265
 266 static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 267 {
 268         return __raw_readw(i2c_dev->base +
 269                                 (i2c_dev->regs[reg] << i2c_dev->reg_shift));
 270 }
 271
 272 static int omap_i2c_init(struct omap_i2c_dev *dev)
 273 {
 274         u16 psc = 0, scll = 0, sclh = 0, buf = 0;
 275         u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
 276         unsigned long fclk_rate = 12000000;
 277         unsigned long timeout;
 278         unsigned long internal_clk = 0;
 279         struct clk *fclk;
 280
 281         if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
 282                 /* Disable I2C controller before soft reset */
 283                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
 284                         omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
 285                                 ~(OMAP_I2C_CON_EN));
 286
 287                 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
 288                 /* For some reason we need to set the EN bit before the
 289                  * reset done bit gets set. */
 290                 timeout = jiffies + OMAP_I2C_TIMEOUT;
 291                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 292                 while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
 293                          SYSS_RESETDONE_MASK)) {
 294                         if (time_after(jiffies, timeout)) {
 295                                 dev_warn(dev->dev, "timeout waiting "
 296                                                 "for controller reset\n");
 297                                 return -ETIMEDOUT;
 298                         }
 299                         msleep(1);
 300                 }
 301
 302                 /* SYSC register is cleared by the reset; rewrite it */
 303                 if (dev->rev == OMAP_I2C_REV_ON_2430) {
 304
 305                         omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
 306                                            SYSC_AUTOIDLE_MASK);
 307
 308                 } else if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
 309                         dev->syscstate = SYSC_AUTOIDLE_MASK;
 310                         dev->syscstate |= SYSC_ENAWAKEUP_MASK;
 311                         dev->syscstate |= (SYSC_IDLEMODE_SMART <<
 312                               __ffs(SYSC_SIDLEMODE_MASK));
 313                         dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
 314                               __ffs(SYSC_CLOCKACTIVITY_MASK));
 315
 316                         omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
 317                                                         dev->syscstate);
 318                         /*
 319                          * Enabling all wakup sources to stop I2C freezing on
 320                          * WFI instruction.
 321                          * REVISIT: Some wkup sources might not be needed.
 322                          */
 323                         dev->westate = OMAP_I2C_WE_ALL;
 324                         omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
 325                                                         dev->westate);
 326                 }
 327         }
 328         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 329
 330         if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
 331                 /*
 332                  * The I2C functional clock is the armxor_ck, so there's
 333                  * no need to get "armxor_ck" separately.  Now, if OMAP2420
 334                  * always returns 12MHz for the functional clock, we can
 335                  * do this bit unconditionally.
 336                  */
 337                 fclk = clk_get(dev->dev, "fck");
 338                 fclk_rate = clk_get_rate(fclk);
 339                 clk_put(fclk);
 340
 341                 /* TRM for 5912 says the I2C clock must be prescaled to be
 342                  * between 7 - 12 MHz. The XOR input clock is typically
 343                  * 12, 13 or 19.2 MHz. So we should have code that produces:
 344                  *
 345                  * XOR MHz      Divider         Prescaler
 346                  * 12           1               0
 347                  * 13           2               1
 348                  * 19.2         2               1
 349                  */
 350                 if (fclk_rate > 12000000)
 351                         psc = fclk_rate / 12000000;
 352         }
 353
 354         if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
 355
 356                 /*
 357                  * HSI2C controller internal clk rate should be 19.2 Mhz for
 358                  * HS and for all modes on 2430. On 34xx we can use lower rate
 359                  * to get longer filter period for better noise suppression.
 360                  * The filter is iclk (fclk for HS) period.
 361                  */
 362                 if (dev->speed > 400 ||
 363                                dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
 364                         internal_clk = 19200;
 365                 else if (dev->speed > 100)
 366                         internal_clk = 9600;
 367                 else
 368                         internal_clk = 4000;
 369                 fclk = clk_get(dev->dev, "fck");
 370                 fclk_rate = clk_get_rate(fclk) / 1000;
 371                 clk_put(fclk);
 372
 373                 /* Compute prescaler divisor */
 374                 psc = fclk_rate / internal_clk;
 375                 psc = psc - 1;
 376
 377                 /* If configured for High Speed */
 378                 if (dev->speed > 400) {
 379                         unsigned long scl;
 380
 381                         /* For first phase of HS mode */
 382                         scl = internal_clk / 400;
 383                         fsscll = scl - (scl / 3) - 7;
 384                         fssclh = (scl / 3) - 5;
 385
 386                         /* For second phase of HS mode */
 387                         scl = fclk_rate / dev->speed;
 388                         hsscll = scl - (scl / 3) - 7;
 389                         hssclh = (scl / 3) - 5;
 390                 } else if (dev->speed > 100) {
 391                         unsigned long scl;
 392
 393                         /* Fast mode */
 394                         scl = internal_clk / dev->speed;
 395                         fsscll = scl - (scl / 3) - 7;
 396                         fssclh = (scl / 3) - 5;
 397                 } else {
 398                         /* Standard mode */
 399                         fsscll = internal_clk / (dev->speed * 2) - 7;
 400                         fssclh = internal_clk / (dev->speed * 2) - 5;
 401                 }
 402                 scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
 403                 sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
 404         } else {
 405                 /* Program desired operating rate */
 406                 fclk_rate /= (psc + 1) * 1000;
 407                 if (psc > 2)
 408                         psc = 2;
 409                 scll = fclk_rate / (dev->speed * 2) - 7 + psc;
 410                 sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
 411         }
 412
 413         /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
 414         omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
 415
 416         /* SCL low and high time values */
 417         omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
 418         omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
 419
 420         if (dev->fifo_size) {
 421                 /* Note: setup required fifo size - 1. RTRSH and XTRSH */
 422                 buf = (dev->fifo_size - 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR |
 423                         (dev->fifo_size - 1) | OMAP_I2C_BUF_TXFIF_CLR;
 424                 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
 425         }
 426
 427         /* Take the I2C module out of reset: */
 428         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 429
 430         /* Enable interrupts */
 431         dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
 432                         OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
 433                         OMAP_I2C_IE_AL)  | ((dev->fifo_size) ?
 434                                 (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
 435         omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
 436         if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
 437                 dev->pscstate = psc;
 438                 dev->scllstate = scll;
 439                 dev->sclhstate = sclh;
 440                 dev->bufstate = buf;
 441         }
 442         return 0;
 443 }
 444
 445 /*
 446  * Waiting on Bus Busy
 447  */
 448 static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
 449 {
 450         unsigned long timeout;
 451
 452         timeout = jiffies + OMAP_I2C_TIMEOUT;
 453         while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
 454                 if (time_after(jiffies, timeout)) {
 455                         dev_warn(dev->dev, "timeout waiting for bus ready\n");
 456                         return -ETIMEDOUT;
 457                 }
 458                 msleep(1);
 459         }
 460
 461         return 0;
 462 }
 463
 464 /*
 465  * Low level master read/write transaction.
 466  */
 467 static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 468                              struct i2c_msg *msg, int stop)
 469 {
 470         struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
 471         unsigned long timeout;
 472         u16 w;
 473
 474         dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
 475                 msg->addr, msg->len, msg->flags, stop);
 476
 477         if (msg->len == 0)
 478                 return -EINVAL;
 479
 480         omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
 481
 482         /* REVISIT: Could the STB bit of I2C_CON be used with probing? */
 483         dev->buf = msg->buf;
 484         dev->buf_len = msg->len;
 485
 486         omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
 487
 488         /* Clear the FIFO Buffers */
 489         w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
 490         w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
 491         omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
 492
 493         INIT_COMPLETION(dev->cmd_complete);
 494         dev->cmd_err = 0;
 495
 496         w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
 497
 498         /* High speed configuration */
 499         if (dev->speed > 400)
 500                 w |= OMAP_I2C_CON_OPMODE_HS;
 501
 502         if (msg->flags & I2C_M_STOP)
 503                 stop = 1;
 504         if (msg->flags & I2C_M_TEN)
 505                 w |= OMAP_I2C_CON_XA;
 506         if (!(msg->flags & I2C_M_RD))
 507                 w |= OMAP_I2C_CON_TRX;
 508
 509         if (!dev->b_hw && stop)
 510                 w |= OMAP_I2C_CON_STP;
 511
 512         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 513
 514         /*
 515          * Don't write stt and stp together on some hardware.
 516          */
 517         if (dev->b_hw && stop) {
 518                 unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
 519                 u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 520                 while (con & OMAP_I2C_CON_STT) {
 521                         con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 522
 523                         /* Let the user know if i2c is in a bad state */
 524                         if (time_after(jiffies, delay)) {
 525                                 dev_err(dev->dev, "controller timed out "
 526                                 "waiting for start condition to finish\n");
 527                                 return -ETIMEDOUT;
 528                         }
 529                         cpu_relax();
 530                 }
 531
 532                 w |= OMAP_I2C_CON_STP;
 533                 w &= ~OMAP_I2C_CON_STT;
 534                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 535         }
 536
 537         /*
 538          * REVISIT: We should abort the transfer on signals, but the bus goes
 539          * into arbitration and we're currently unable to recover from it.
 540          */
 541         timeout = wait_for_completion_timeout(&dev->cmd_complete,
 542                                                 OMAP_I2C_TIMEOUT);
 543         dev->buf_len = 0;
 544         if (timeout == 0) {
 545                 dev_err(dev->dev, "controller timed out\n");
 546                 omap_i2c_init(dev);
 547                 return -ETIMEDOUT;
 548         }
 549
 550         if (likely(!dev->cmd_err))
 551                 return 0;
 552
 553         /* We have an error */
 554         if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
 555                             OMAP_I2C_STAT_XUDF)) {
 556                 omap_i2c_init(dev);
 557                 return -EIO;
 558         }
 559
 560         if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
 561                 if (msg->flags & I2C_M_IGNORE_NAK)
 562                         return 0;
 563                 if (stop) {
 564                         w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 565                         w |= OMAP_I2C_CON_STP;
 566                         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 567                 }
 568                 return -EREMOTEIO;
 569         }
 570         return -EIO;
 571 }
 572
 573
 574 /*
 575  * Prepare controller for a transaction and call omap_i2c_xfer_msg
 576  * to do the work during IRQ processing.
 577  */
 578 static int
 579 omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 580 {
 581         struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
 582         int i;
 583         int r;
 584
 585         r = pm_runtime_get_sync(dev->dev);
 586         if (IS_ERR_VALUE(r))
 587                 goto out;
 588
 589         r = omap_i2c_wait_for_bb(dev);
 590         if (r < 0)
 591                 goto out;
 592
 593         if (dev->set_mpu_wkup_lat != NULL)
 594                 dev->set_mpu_wkup_lat(dev->dev, dev->latency);
 595
 596         for (i = 0; i < num; i++) {
 597                 r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
 598                 if (r != 0)
 599                         break;
 600         }
 601
 602         if (dev->set_mpu_wkup_lat != NULL)
 603                 dev->set_mpu_wkup_lat(dev->dev, -1);
 604
 605         if (r == 0)
 606                 r = num;
 607
 608         omap_i2c_wait_for_bb(dev);
 609 out:
 610         pm_runtime_put(dev->dev);
 611         return r;
 612 }
 613
 614 static u32
 615 omap_i2c_func(struct i2c_adapter *adap)
 616 {
 617         return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
 618                I2C_FUNC_PROTOCOL_MANGLING;
 619 }
 620
 621 static inline void
 622 omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
 623 {
 624         dev->cmd_err |= err;
 625         complete(&dev->cmd_complete);
 626 }
 627
 628 static inline void
 629 omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
 630 {
 631         omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
 632 }
 633
 634 static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
 635 {
 636         /*
 637          * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
 638          * Not applicable for OMAP4.
 639          * Under certain rare conditions, RDR could be set again
 640          * when the bus is busy, then ignore the interrupt and
 641          * clear the interrupt.
 642          */
 643         if (stat & OMAP_I2C_STAT_RDR) {
 644                 /* Step 1: If RDR is set, clear it */
 645                 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
 646
 647                 /* Step 2: */
 648                 if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
 649                                                 & OMAP_I2C_STAT_BB)) {
 650
 651                         /* Step 3: */
 652                         if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
 653                                                 & OMAP_I2C_STAT_RDR) {
 654                                 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
 655                                 dev_dbg(dev->dev, "RDR when bus is busy.\n");
 656                         }
 657
 658                 }
 659         }
 660 }
 661
 662 /* rev1 devices are apparently only on some 15xx */
 663 #ifdef CONFIG_ARCH_OMAP15XX
 664
 665 static irqreturn_t
 666 omap_i2c_omap1_isr(int this_irq, void *dev_id)
 667 {
 668         struct omap_i2c_dev *dev = dev_id;
 669         u16 iv, w;
 670
 671         if (pm_runtime_suspended(dev->dev))
 672                 return IRQ_NONE;
 673
 674         iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
 675         switch (iv) {
 676         case 0x00:      /* None */
 677                 break;
 678         case 0x01:      /* Arbitration lost */
 679                 dev_err(dev->dev, "Arbitration lost\n");
 680                 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
 681                 break;
 682         case 0x02:      /* No acknowledgement */
 683                 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
 684                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
 685                 break;
 686         case 0x03:      /* Register access ready */
 687                 omap_i2c_complete_cmd(dev, 0);
 688                 break;
 689         case 0x04:      /* Receive data ready */
 690                 if (dev->buf_len) {
 691                         w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 692                         *dev->buf++ = w;
 693                         dev->buf_len--;
 694                         if (dev->buf_len) {
 695                                 *dev->buf++ = w >> 8;
 696                                 dev->buf_len--;
 697                         }
 698                 } else
 699                         dev_err(dev->dev, "RRDY IRQ while no data requested\n");
 700                 break;
 701         case 0x05:      /* Transmit data ready */
 702                 if (dev->buf_len) {
 703                         w = *dev->buf++;
 704                         dev->buf_len--;
 705                         if (dev->buf_len) {
 706                                 w |= *dev->buf++ << 8;
 707                                 dev->buf_len--;
 708                         }
 709                         omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 710                 } else
 711                         dev_err(dev->dev, "XRDY IRQ while no data to send\n");
 712                 break;
 713         default:
 714                 return IRQ_NONE;
 715         }
 716
 717         return IRQ_HANDLED;
 718 }
 719 #else
 720 #define omap_i2c_omap1_isr              NULL
 721 #endif
 722
 723 /*
 724  * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing
 725  * data to DATA_REG. Otherwise some data bytes can be lost while transferring
 726  * them from the memory to the I2C interface.
 727  */
 728 static int errata_omap3_i462(struct omap_i2c_dev *dev, u16 *stat, int *err)
 729 {
 730         unsigned long timeout = 10000;
 731
 732         while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
 733                 if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
 734                         omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY |
 735                                                         OMAP_I2C_STAT_XDR));
 736                         return -ETIMEDOUT;
 737                 }
 738
 739                 cpu_relax();
 740                 *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 741         }
 742
 743         if (!timeout) {
 744                 dev_err(dev->dev, "timeout waiting on XUDF bit\n");
 745                 return 0;
 746         }
 747
 748         *err |= OMAP_I2C_STAT_XUDF;
 749         return 0;
 750 }
 751
 752 static irqreturn_t
 753 omap_i2c_isr(int this_irq, void *dev_id)
 754 {
 755         struct omap_i2c_dev *dev = dev_id;
 756         u16 bits;
 757         u16 stat, w;
 758         int err, count = 0;
 759
 760         if (pm_runtime_suspended(dev->dev))
 761                 return IRQ_NONE;
 762
 763         bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
 764         while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) {
 765                 dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
 766                 if (count++ == 100) {
 767                         dev_warn(dev->dev, "Too much work in one IRQ\n");
 768                         break;
 769                 }
 770
 771                 err = 0;
 772 complete:
 773                 /*
 774                  * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
 775                  * acked after the data operation is complete.
 776                  * Ref: TRM SWPU114Q Figure 18-31
 777                  */
 778                 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat &
 779                                 ~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
 780                                 OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
 781
 782                 if (stat & OMAP_I2C_STAT_NACK)
 783                         err |= OMAP_I2C_STAT_NACK;
 784
 785                 if (stat & OMAP_I2C_STAT_AL) {
 786                         dev_err(dev->dev, "Arbitration lost\n");
 787                         err |= OMAP_I2C_STAT_AL;
 788                 }
 789                 /*
 790                  * ProDB0017052: Clear ARDY bit twice
 791                  */
 792                 if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
 793                                         OMAP_I2C_STAT_AL)) {
 794                         omap_i2c_ack_stat(dev, stat &
 795                                 (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
 796                                 OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR |
 797                                 OMAP_I2C_STAT_ARDY));
 798                         omap_i2c_complete_cmd(dev, err);
 799                         return IRQ_HANDLED;
 800                 }
 801                 if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
 802                         u8 num_bytes = 1;
 803
 804                         if (dev->errata & I2C_OMAP_ERRATA_I207)
 805                                 i2c_omap_errata_i207(dev, stat);
 806
 807                         if (dev->fifo_size) {
 808                                 if (stat & OMAP_I2C_STAT_RRDY)
 809                                         num_bytes = dev->fifo_size;
 810                                 else    /* read RXSTAT on RDR interrupt */
 811                                         num_bytes = (omap_i2c_read_reg(dev,
 812                                                         OMAP_I2C_BUFSTAT_REG)
 813                                                         >> 8) & 0x3F;
 814                         }
 815                         while (num_bytes) {
 816                                 num_bytes--;
 817                                 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 818                                 if (dev->buf_len) {
 819                                         *dev->buf++ = w;
 820                                         dev->buf_len--;
 821                                         /*
 822                                          * Data reg in 2430, omap3 and
 823                                          * omap4 is 8 bit wide
 824                                          */
 825                                         if (dev->flags &
 826                                                  OMAP_I2C_FLAG_16BIT_DATA_REG) {
 827                                                 if (dev->buf_len) {
 828                                                         *dev->buf++ = w >> 8;
 829                                                         dev->buf_len--;
 830                                                 }
 831                                         }
 832                                 } else {
 833                                         if (stat & OMAP_I2C_STAT_RRDY)
 834                                                 dev_err(dev->dev,
 835                                                         "RRDY IRQ while no data"
 836                                                                 " requested\n");
 837                                         if (stat & OMAP_I2C_STAT_RDR)
 838                                                 dev_err(dev->dev,
 839                                                         "RDR IRQ while no data"
 840                                                                 " requested\n");
 841                                         break;
 842                                 }
 843                         }
 844                         omap_i2c_ack_stat(dev,
 845                                 stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
 846                         continue;
 847                 }
 848                 if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
 849                         u8 num_bytes = 1;
 850                         if (dev->fifo_size) {
 851                                 if (stat & OMAP_I2C_STAT_XRDY)
 852                                         num_bytes = dev->fifo_size;
 853                                 else    /* read TXSTAT on XDR interrupt */
 854                                         num_bytes = omap_i2c_read_reg(dev,
 855                                                         OMAP_I2C_BUFSTAT_REG)
 856                                                         & 0x3F;
 857                         }
 858                         while (num_bytes) {
 859                                 num_bytes--;
 860                                 w = 0;
 861                                 if (dev->buf_len) {
 862                                         w = *dev->buf++;
 863                                         dev->buf_len--;
 864                                         /*
 865                                          * Data reg in 2430, omap3 and
 866                                          * omap4 is 8 bit wide
 867                                          */
 868                                         if (dev->flags &
 869                                                  OMAP_I2C_FLAG_16BIT_DATA_REG) {
 870                                                 if (dev->buf_len) {
 871                                                         w |= *dev->buf++ << 8;
 872                                                         dev->buf_len--;
 873                                                 }
 874                                         }
 875                                 } else {
 876                                         if (stat & OMAP_I2C_STAT_XRDY)
 877                                                 dev_err(dev->dev,
 878                                                         "XRDY IRQ while no "
 879                                                         "data to send\n");
 880                                         if (stat & OMAP_I2C_STAT_XDR)
 881                                                 dev_err(dev->dev,
 882                                                         "XDR IRQ while no "
 883                                                         "data to send\n");
 884                                         break;
 885                                 }
 886
 887                                 if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
 888                                     errata_omap3_i462(dev, &stat, &err))
 889                                         goto complete;
 890
 891                                 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 892                         }
 893                         omap_i2c_ack_stat(dev,
 894                                 stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
 895                         continue;
 896                 }
 897                 if (stat & OMAP_I2C_STAT_ROVR) {
 898                         dev_err(dev->dev, "Receive overrun\n");
 899                         dev->cmd_err |= OMAP_I2C_STAT_ROVR;
 900                 }
 901                 if (stat & OMAP_I2C_STAT_XUDF) {
 902                         dev_err(dev->dev, "Transmit underflow\n");
 903                         dev->cmd_err |= OMAP_I2C_STAT_XUDF;
 904                 }
 905         }
 906
 907         return count ? IRQ_HANDLED : IRQ_NONE;
 908 }
 909
 910 static const struct i2c_algorithm omap_i2c_algo = {
 911         .master_xfer    = omap_i2c_xfer,
 912         .functionality  = omap_i2c_func,
 913 };
 914
 915 #ifdef CONFIG_OF
 916 static struct omap_i2c_bus_platform_data omap3_pdata = {
 917         .rev = OMAP_I2C_IP_VERSION_1,
 918         .flags = OMAP_I2C_FLAG_APPLY_ERRATA_I207 |
 919                  OMAP_I2C_FLAG_RESET_REGS_POSTIDLE |
 920                  OMAP_I2C_FLAG_BUS_SHIFT_2,
 921 };
 922
 923 static struct omap_i2c_bus_platform_data omap4_pdata = {
 924         .rev = OMAP_I2C_IP_VERSION_2,
 925 };
 926
 927 static const struct of_device_id omap_i2c_of_match[] = {
 928         {
 929                 .compatible = "ti,omap4-i2c",
 930                 .data = &omap4_pdata,
 931         },
 932         {
 933                 .compatible = "ti,omap3-i2c",
 934                 .data = &omap3_pdata,
 935         },
 936         { },
 937 };
 938 MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
 939 #endif
 940
 941 static int __devinit
 942 omap_i2c_probe(struct platform_device *pdev)
 943 {
 944         struct omap_i2c_dev     *dev;
 945         struct i2c_adapter      *adap;
 946         struct resource         *mem, *irq, *ioarea;
 947         const struct omap_i2c_bus_platform_data *pdata =
 948                 pdev->dev.platform_data;
 949         struct device_node      *node = pdev->dev.of_node;
 950         const struct of_device_id *match;
 951         irq_handler_t isr;
 952         int r;
 953
 954         /* NOTE: driver uses the static register mapping */
 955         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 956         if (!mem) {
 957                 dev_err(&pdev->dev, "no mem resource?\n");
 958                 return -ENODEV;
 959         }
 960         irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 961         if (!irq) {
 962                 dev_err(&pdev->dev, "no irq resource?\n");
 963                 return -ENODEV;
 964         }
 965
 966         ioarea = request_mem_region(mem->start, resource_size(mem),
 967                         pdev->name);
 968         if (!ioarea) {
 969                 dev_err(&pdev->dev, "I2C region already claimed\n");
 970                 return -EBUSY;
 971         }
 972
 973         dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
 974         if (!dev) {
 975                 r = -ENOMEM;
 976                 goto err_release_region;
 977         }
 978
 979         match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
 980         if (match) {
 981                 u32 freq = 100000; /* default to 100000 Hz */
 982
 983                 pdata = match->data;
 984                 dev->dtrev = pdata->rev;
 985                 dev->flags = pdata->flags;
 986
 987                 of_property_read_u32(node, "clock-frequency", &freq);
 988                 /* convert DT freq value in Hz into kHz for speed */
 989                 dev->speed = freq / 1000;
 990         } else if (pdata != NULL) {
 991                 dev->speed = pdata->clkrate;
 992                 dev->flags = pdata->flags;
 993                 dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
 994                 dev->dtrev = pdata->rev;
 995         }
 996
 997         dev->dev = &pdev->dev;
 998         dev->irq = irq->start;
 999         dev->base = ioremap(mem->start, resource_size(mem));
1000         if (!dev->base) {
1001                 r = -ENOMEM;
1002                 goto err_free_mem;
1003         }
1004
1005         platform_set_drvdata(pdev, dev);
1006         init_completion(&dev->cmd_complete);
1007
1008         dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
1009
1010         if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
1011                 dev->regs = (u8 *)reg_map_ip_v2;
1012         else
1013                 dev->regs = (u8 *)reg_map_ip_v1;
1014
1015         pm_runtime_enable(dev->dev);
1016         r = pm_runtime_get_sync(dev->dev);
1017         if (IS_ERR_VALUE(r))
1018                 goto err_free_mem;
1019
1020         dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
1021
1022         dev->errata = 0;
1023
1024         if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207)
1025                 dev->errata |= I2C_OMAP_ERRATA_I207;
1026
1027         if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
1028                 dev->errata |= I2C_OMAP_ERRATA_I462;
1029
1030         if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
1031                 u16 s;
1032
1033                 /* Set up the fifo size - Get total size */
1034                 s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
1035                 dev->fifo_size = 0x8 << s;
1036
1037                 /*
1038                  * Set up notification threshold as half the total available
1039                  * size. This is to ensure that we can handle the status on int
1040                  * call back latencies.
1041                  */
1042
1043                 dev->fifo_size = (dev->fifo_size / 2);
1044
1045                 if (dev->rev >= OMAP_I2C_REV_ON_3630_4430)
1046                         dev->b_hw = 0; /* Disable hardware fixes */
1047                 else
1048                         dev->b_hw = 1; /* Enable hardware fixes */
1049
1050                 /* calculate wakeup latency constraint for MPU */
1051                 if (dev->set_mpu_wkup_lat != NULL)
1052                         dev->latency = (1000000 * dev->fifo_size) /
1053                                        (1000 * dev->speed / 8);
1054         }
1055
1056         /* reset ASAP, clearing any IRQs */
1057         omap_i2c_init(dev);
1058
1059         isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr :
1060                                                                    omap_i2c_isr;
1061         r = request_irq(dev->irq, isr, IRQF_NO_SUSPEND, pdev->name, dev);
1062
1063         if (r) {
1064                 dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
1065                 goto err_unuse_clocks;
1066         }
1067
1068         dev_info(dev->dev, "bus %d rev%d.%d.%d at %d kHz\n", pdev->id,
1069                  dev->dtrev, dev->rev >> 4, dev->rev & 0xf, dev->speed);
1070
1071         adap = &dev->adapter;
1072         i2c_set_adapdata(adap, dev);
1073         adap->owner = THIS_MODULE;
1074         adap->class = I2C_CLASS_HWMON;
1075         strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
1076         adap->algo = &omap_i2c_algo;
1077         adap->dev.parent = &pdev->dev;
1078         adap->dev.of_node = pdev->dev.of_node;
1079
1080         /* i2c device drivers may be active on return from add_adapter() */
1081         adap->nr = pdev->id;
1082         r = i2c_add_numbered_adapter(adap);
1083         if (r) {
1084                 dev_err(dev->dev, "failure adding adapter\n");
1085                 goto err_free_irq;
1086         }
1087
1088         of_i2c_register_devices(adap);
1089
1090         pm_runtime_put(dev->dev);
1091
1092         return 0;
1093
1094 err_free_irq:
1095         free_irq(dev->irq, dev);
1096 err_unuse_clocks:
1097         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1098         pm_runtime_put(dev->dev);
1099         iounmap(dev->base);
1100         pm_runtime_disable(&pdev->dev);
1101 err_free_mem:
1102         platform_set_drvdata(pdev, NULL);
1103         kfree(dev);
1104 err_release_region:
1105         release_mem_region(mem->start, resource_size(mem));
1106
1107         return r;
1108 }
1109
1110 static int __devexit omap_i2c_remove(struct platform_device *pdev)
1111 {
1112         struct omap_i2c_dev     *dev = platform_get_drvdata(pdev);
1113         struct resource         *mem;
1114         int ret;
1115
1116         platform_set_drvdata(pdev, NULL);
1117
1118         free_irq(dev->irq, dev);
1119         i2c_del_adapter(&dev->adapter);
1120         ret = pm_runtime_get_sync(&pdev->dev);
1121         if (IS_ERR_VALUE(ret))
1122                 return ret;
1123
1124         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1125         pm_runtime_put(&pdev->dev);
1126         pm_runtime_disable(&pdev->dev);
1127         iounmap(dev->base);
1128         kfree(dev);
1129         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1130         release_mem_region(mem->start, resource_size(mem));
1131         return 0;
1132 }
1133
1134 #ifdef CONFIG_PM
1135 #ifdef CONFIG_PM_RUNTIME
1136 static int omap_i2c_runtime_suspend(struct device *dev)
1137 {
1138         struct platform_device *pdev = to_platform_device(dev);
1139         struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1140         u16 iv;
1141
1142         _dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
1143
1144         omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
1145
1146         if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
1147                 iv = omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
1148         } else {
1149                 omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
1150
1151                 /* Flush posted write */
1152                 omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
1153         }
1154
1155         return 0;
1156 }
1157
1158 static int omap_i2c_runtime_resume(struct device *dev)
1159 {
1160         struct platform_device *pdev = to_platform_device(dev);
1161         struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1162
1163         if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
1164                 omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
1165                 omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
1166                 omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
1167                 omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
1168                 omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
1169                 omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
1170                 omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
1171                 omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
1172         }
1173
1174         /*
1175          * Don't write to this register if the IE state is 0 as it can
1176          * cause deadlock.
1177          */
1178         if (_dev->iestate)
1179                 omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
1180
1181         return 0;
1182 }
1183 #endif /* CONFIG_PM_RUNTIME */
1184
1185 static struct dev_pm_ops omap_i2c_pm_ops = {
1186         SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
1187                            omap_i2c_runtime_resume, NULL)
1188 };
1189 #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
1190 #else
1191 #define OMAP_I2C_PM_OPS NULL
1192 #endif /* CONFIG_PM */
1193
1194 static struct platform_driver omap_i2c_driver = {
1195         .probe          = omap_i2c_probe,
1196         .remove         = __devexit_p(omap_i2c_remove),
1197         .driver         = {
1198                 .name   = "omap_i2c",
1199                 .owner  = THIS_MODULE,
1200                 .pm     = OMAP_I2C_PM_OPS,
1201                 .of_match_table = of_match_ptr(omap_i2c_of_match),
1202         },
1203 };
1204
1205 /* I2C may be needed to bring up other drivers */
1206 static int __init
1207 omap_i2c_init_driver(void)
1208 {
1209         return platform_driver_register(&omap_i2c_driver);
1210 }
1211 subsys_initcall(omap_i2c_init_driver);
1212
1213 static void __exit omap_i2c_exit_driver(void)
1214 {
1215         platform_driver_unregister(&omap_i2c_driver);
1216 }
1217 module_exit(omap_i2c_exit_driver);
1218
1219 MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1220 MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1221 MODULE_LICENSE("GPL");
1222 MODULE_ALIAS("platform:omap_i2c");