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 <[email protected]>
  11  *      Imre Deak <[email protected]>
  12  *      Juha Yrjölä <[email protected]>
  13  *      Syed Khasim <[email protected]>
  14  *      Nishant Menon <[email protected]>
  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
  27 #include <linux/module.h>
  28 #include <linux/delay.h>
  29 #include <linux/i2c.h>
  30 #include <linux/err.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/completion.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/clk.h>
  35 #include <linux/io.h>
  36 #include <linux/of.h>
  37 #include <linux/of_device.h>
  38 #include <linux/slab.h>
  39 #include <linux/i2c-omap.h>
  40 #include <linux/pm_runtime.h>
  41
  42 /* I2C controller revisions */
  43 #define OMAP_I2C_OMAP1_REV_2            0x20
  44
  45 /* I2C controller revisions present on specific hardware */
  46 #define OMAP_I2C_REV_ON_2430            0x00000036
  47 #define OMAP_I2C_REV_ON_3430_3530       0x0000003C
  48 #define OMAP_I2C_REV_ON_3630            0x00000040
  49 #define OMAP_I2C_REV_ON_4430_PLUS       0x50400002
  50
  51 /* timeout waiting for the controller to respond */
  52 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
  53
  54 /* timeout for pm runtime autosuspend */
  55 #define OMAP_I2C_PM_TIMEOUT             1000    /* ms */
  56
  57 /* timeout for making decision on bus free status */
  58 #define OMAP_I2C_BUS_FREE_TIMEOUT (msecs_to_jiffies(10))
  59
  60 /* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
  61 enum {
  62         OMAP_I2C_REV_REG = 0,
  63         OMAP_I2C_IE_REG,
  64         OMAP_I2C_STAT_REG,
  65         OMAP_I2C_IV_REG,
  66         OMAP_I2C_WE_REG,
  67         OMAP_I2C_SYSS_REG,
  68         OMAP_I2C_BUF_REG,
  69         OMAP_I2C_CNT_REG,
  70         OMAP_I2C_DATA_REG,
  71         OMAP_I2C_SYSC_REG,
  72         OMAP_I2C_CON_REG,
  73         OMAP_I2C_OA_REG,
  74         OMAP_I2C_SA_REG,
  75         OMAP_I2C_PSC_REG,
  76         OMAP_I2C_SCLL_REG,
  77         OMAP_I2C_SCLH_REG,
  78         OMAP_I2C_SYSTEST_REG,
  79         OMAP_I2C_BUFSTAT_REG,
  80         /* only on OMAP4430 */
  81         OMAP_I2C_IP_V2_REVNB_LO,
  82         OMAP_I2C_IP_V2_REVNB_HI,
  83         OMAP_I2C_IP_V2_IRQSTATUS_RAW,
  84         OMAP_I2C_IP_V2_IRQENABLE_SET,
  85         OMAP_I2C_IP_V2_IRQENABLE_CLR,
  86 };
  87
  88 /* I2C Interrupt Enable Register (OMAP_I2C_IE): */
  89 #define OMAP_I2C_IE_XDR         (1 << 14)       /* TX Buffer drain int enable */
  90 #define OMAP_I2C_IE_RDR         (1 << 13)       /* RX Buffer drain int enable */
  91 #define OMAP_I2C_IE_XRDY        (1 << 4)        /* TX data ready int enable */
  92 #define OMAP_I2C_IE_RRDY        (1 << 3)        /* RX data ready int enable */
  93 #define OMAP_I2C_IE_ARDY        (1 << 2)        /* Access ready int enable */
  94 #define OMAP_I2C_IE_NACK        (1 << 1)        /* No ack interrupt enable */
  95 #define OMAP_I2C_IE_AL          (1 << 0)        /* Arbitration lost int ena */
  96
  97 /* I2C Status Register (OMAP_I2C_STAT): */
  98 #define OMAP_I2C_STAT_XDR       (1 << 14)       /* TX Buffer draining */
  99 #define OMAP_I2C_STAT_RDR       (1 << 13)       /* RX Buffer draining */
 100 #define OMAP_I2C_STAT_BB        (1 << 12)       /* Bus busy */
 101 #define OMAP_I2C_STAT_ROVR      (1 << 11)       /* Receive overrun */
 102 #define OMAP_I2C_STAT_XUDF      (1 << 10)       /* Transmit underflow */
 103 #define OMAP_I2C_STAT_AAS       (1 << 9)        /* Address as slave */
 104 #define OMAP_I2C_STAT_BF        (1 << 8)        /* Bus Free */
 105 #define OMAP_I2C_STAT_XRDY      (1 << 4)        /* Transmit data ready */
 106 #define OMAP_I2C_STAT_RRDY      (1 << 3)        /* Receive data ready */
 107 #define OMAP_I2C_STAT_ARDY      (1 << 2)        /* Register access ready */
 108 #define OMAP_I2C_STAT_NACK      (1 << 1)        /* No ack interrupt enable */
 109 #define OMAP_I2C_STAT_AL        (1 << 0)        /* Arbitration lost int ena */
 110
 111 /* I2C WE wakeup enable register */
 112 #define OMAP_I2C_WE_XDR_WE      (1 << 14)       /* TX drain wakup */
 113 #define OMAP_I2C_WE_RDR_WE      (1 << 13)       /* RX drain wakeup */
 114 #define OMAP_I2C_WE_AAS_WE      (1 << 9)        /* Address as slave wakeup*/
 115 #define OMAP_I2C_WE_BF_WE       (1 << 8)        /* Bus free wakeup */
 116 #define OMAP_I2C_WE_STC_WE      (1 << 6)        /* Start condition wakeup */
 117 #define OMAP_I2C_WE_GC_WE       (1 << 5)        /* General call wakeup */
 118 #define OMAP_I2C_WE_DRDY_WE     (1 << 3)        /* TX/RX data ready wakeup */
 119 #define OMAP_I2C_WE_ARDY_WE     (1 << 2)        /* Reg access ready wakeup */
 120 #define OMAP_I2C_WE_NACK_WE     (1 << 1)        /* No acknowledgment wakeup */
 121 #define OMAP_I2C_WE_AL_WE       (1 << 0)        /* Arbitration lost wakeup */
 122
 123 #define OMAP_I2C_WE_ALL         (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
 124                                 OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
 125                                 OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
 126                                 OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
 127                                 OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
 128
 129 /* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
 130 #define OMAP_I2C_BUF_RDMA_EN    (1 << 15)       /* RX DMA channel enable */
 131 #define OMAP_I2C_BUF_RXFIF_CLR  (1 << 14)       /* RX FIFO Clear */
 132 #define OMAP_I2C_BUF_XDMA_EN    (1 << 7)        /* TX DMA channel enable */
 133 #define OMAP_I2C_BUF_TXFIF_CLR  (1 << 6)        /* TX FIFO Clear */
 134
 135 /* I2C Configuration Register (OMAP_I2C_CON): */
 136 #define OMAP_I2C_CON_EN         (1 << 15)       /* I2C module enable */
 137 #define OMAP_I2C_CON_BE         (1 << 14)       /* Big endian mode */
 138 #define OMAP_I2C_CON_OPMODE_HS  (1 << 12)       /* High Speed support */
 139 #define OMAP_I2C_CON_STB        (1 << 11)       /* Start byte mode (master) */
 140 #define OMAP_I2C_CON_MST        (1 << 10)       /* Master/slave mode */
 141 #define OMAP_I2C_CON_TRX        (1 << 9)        /* TX/RX mode (master only) */
 142 #define OMAP_I2C_CON_XA         (1 << 8)        /* Expand address */
 143 #define OMAP_I2C_CON_RM         (1 << 2)        /* Repeat mode (master only) */
 144 #define OMAP_I2C_CON_STP        (1 << 1)        /* Stop cond (master only) */
 145 #define OMAP_I2C_CON_STT        (1 << 0)        /* Start condition (master) */
 146
 147 /* I2C SCL time value when Master */
 148 #define OMAP_I2C_SCLL_HSSCLL    8
 149 #define OMAP_I2C_SCLH_HSSCLH    8
 150
 151 /* I2C System Test Register (OMAP_I2C_SYSTEST): */
 152 #define OMAP_I2C_SYSTEST_ST_EN          (1 << 15)       /* System test enable */
 153 #define OMAP_I2C_SYSTEST_FREE           (1 << 14)       /* Free running mode */
 154 #define OMAP_I2C_SYSTEST_TMODE_MASK     (3 << 12)       /* Test mode select */
 155 #define OMAP_I2C_SYSTEST_TMODE_SHIFT    (12)            /* Test mode select */
 156 /* Functional mode */
 157 #define OMAP_I2C_SYSTEST_SCL_I_FUNC     (1 << 8)        /* SCL line input value */
 158 #define OMAP_I2C_SYSTEST_SCL_O_FUNC     (1 << 7)        /* SCL line output value */
 159 #define OMAP_I2C_SYSTEST_SDA_I_FUNC     (1 << 6)        /* SDA line input value */
 160 #define OMAP_I2C_SYSTEST_SDA_O_FUNC     (1 << 5)        /* SDA line output value */
 161 /* SDA/SCL IO mode */
 162 #define OMAP_I2C_SYSTEST_SCL_I          (1 << 3)        /* SCL line sense in */
 163 #define OMAP_I2C_SYSTEST_SCL_O          (1 << 2)        /* SCL line drive out */
 164 #define OMAP_I2C_SYSTEST_SDA_I          (1 << 1)        /* SDA line sense in */
 165 #define OMAP_I2C_SYSTEST_SDA_O          (1 << 0)        /* SDA line drive out */
 166
 167 /* OCP_SYSSTATUS bit definitions */
 168 #define SYSS_RESETDONE_MASK             (1 << 0)
 169
 170 /* OCP_SYSCONFIG bit definitions */
 171 #define SYSC_CLOCKACTIVITY_MASK         (0x3 << 8)
 172 #define SYSC_SIDLEMODE_MASK             (0x3 << 3)
 173 #define SYSC_ENAWAKEUP_MASK             (1 << 2)
 174 #define SYSC_SOFTRESET_MASK             (1 << 1)
 175 #define SYSC_AUTOIDLE_MASK              (1 << 0)
 176
 177 #define SYSC_IDLEMODE_SMART             0x2
 178 #define SYSC_CLOCKACTIVITY_FCLK         0x2
 179
 180 /* Errata definitions */
 181 #define I2C_OMAP_ERRATA_I207            (1 << 0)
 182 #define I2C_OMAP_ERRATA_I462            (1 << 1)
 183
 184 #define OMAP_I2C_IP_V2_INTERRUPTS_MASK  0x6FFF
 185
 186 struct omap_i2c_dev {
 187         spinlock_t              lock;           /* IRQ synchronization */
 188         struct device           *dev;
 189         void __iomem            *base;          /* virtual */
 190         int                     irq;
 191         int                     reg_shift;      /* bit shift for I2C register addresses */
 192         struct completion       cmd_complete;
 193         struct resource         *ioarea;
 194         u32                     latency;        /* maximum mpu wkup latency */
 195         void                    (*set_mpu_wkup_lat)(struct device *dev,
 196                                                     long latency);
 197         u32                     speed;          /* Speed of bus in kHz */
 198         u32                     flags;
 199         u16                     scheme;
 200         u16                     cmd_err;
 201         u8                      *buf;
 202         u8                      *regs;
 203         size_t                  buf_len;
 204         struct i2c_adapter      adapter;
 205         u8                      threshold;
 206         u8                      fifo_size;      /* use as flag and value
 207                                                  * fifo_size==0 implies no fifo
 208                                                  * if set, should be trsh+1
 209                                                  */
 210         u32                     rev;
 211         unsigned                b_hw:1;         /* bad h/w fixes */
 212         unsigned                bb_valid:1;     /* true when BB-bit reflects
 213                                                  * the I2C bus state
 214                                                  */
 215         unsigned                receiver:1;     /* true when we're in receiver mode */
 216         u16                     iestate;        /* Saved interrupt register */
 217         u16                     pscstate;
 218         u16                     scllstate;
 219         u16                     sclhstate;
 220         u16                     syscstate;
 221         u16                     westate;
 222         u16                     errata;
 223 };
 224
 225 static const u8 reg_map_ip_v1[] = {
 226         [OMAP_I2C_REV_REG] = 0x00,
 227         [OMAP_I2C_IE_REG] = 0x01,
 228         [OMAP_I2C_STAT_REG] = 0x02,
 229         [OMAP_I2C_IV_REG] = 0x03,
 230         [OMAP_I2C_WE_REG] = 0x03,
 231         [OMAP_I2C_SYSS_REG] = 0x04,
 232         [OMAP_I2C_BUF_REG] = 0x05,
 233         [OMAP_I2C_CNT_REG] = 0x06,
 234         [OMAP_I2C_DATA_REG] = 0x07,
 235         [OMAP_I2C_SYSC_REG] = 0x08,
 236         [OMAP_I2C_CON_REG] = 0x09,
 237         [OMAP_I2C_OA_REG] = 0x0a,
 238         [OMAP_I2C_SA_REG] = 0x0b,
 239         [OMAP_I2C_PSC_REG] = 0x0c,
 240         [OMAP_I2C_SCLL_REG] = 0x0d,
 241         [OMAP_I2C_SCLH_REG] = 0x0e,
 242         [OMAP_I2C_SYSTEST_REG] = 0x0f,
 243         [OMAP_I2C_BUFSTAT_REG] = 0x10,
 244 };
 245
 246 static const u8 reg_map_ip_v2[] = {
 247         [OMAP_I2C_REV_REG] = 0x04,
 248         [OMAP_I2C_IE_REG] = 0x2c,
 249         [OMAP_I2C_STAT_REG] = 0x28,
 250         [OMAP_I2C_IV_REG] = 0x34,
 251         [OMAP_I2C_WE_REG] = 0x34,
 252         [OMAP_I2C_SYSS_REG] = 0x90,
 253         [OMAP_I2C_BUF_REG] = 0x94,
 254         [OMAP_I2C_CNT_REG] = 0x98,
 255         [OMAP_I2C_DATA_REG] = 0x9c,
 256         [OMAP_I2C_SYSC_REG] = 0x10,
 257         [OMAP_I2C_CON_REG] = 0xa4,
 258         [OMAP_I2C_OA_REG] = 0xa8,
 259         [OMAP_I2C_SA_REG] = 0xac,
 260         [OMAP_I2C_PSC_REG] = 0xb0,
 261         [OMAP_I2C_SCLL_REG] = 0xb4,
 262         [OMAP_I2C_SCLH_REG] = 0xb8,
 263         [OMAP_I2C_SYSTEST_REG] = 0xbC,
 264         [OMAP_I2C_BUFSTAT_REG] = 0xc0,
 265         [OMAP_I2C_IP_V2_REVNB_LO] = 0x00,
 266         [OMAP_I2C_IP_V2_REVNB_HI] = 0x04,
 267         [OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24,
 268         [OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c,
 269         [OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
 270 };
 271
 272 static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
 273                                       int reg, u16 val)
 274 {
 275         writew_relaxed(val, i2c_dev->base +
 276                         (i2c_dev->regs[reg] << i2c_dev->reg_shift));
 277 }
 278
 279 static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 280 {
 281         return readw_relaxed(i2c_dev->base +
 282                                 (i2c_dev->regs[reg] << i2c_dev->reg_shift));
 283 }
 284
 285 static void __omap_i2c_init(struct omap_i2c_dev *dev)
 286 {
 287
 288         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 289
 290         /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
 291         omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
 292
 293         /* SCL low and high time values */
 294         omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
 295         omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
 296         if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
 297                 omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
 298
 299         /* Take the I2C module out of reset: */
 300         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 301
 302         /*
 303          * NOTE: right after setting CON_EN, STAT_BB could be 0 while the
 304          * bus is busy. It will be changed to 1 on the next IP FCLK clock.
 305          * udelay(1) will be enough to fix that.
 306          */
 307
 308         /*
 309          * Don't write to this register if the IE state is 0 as it can
 310          * cause deadlock.
 311          */
 312         if (dev->iestate)
 313                 omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
 314 }
 315
 316 static int omap_i2c_reset(struct omap_i2c_dev *dev)
 317 {
 318         unsigned long timeout;
 319         u16 sysc;
 320
 321         if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
 322                 sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG);
 323
 324                 /* Disable I2C controller before soft reset */
 325                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
 326                         omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
 327                                 ~(OMAP_I2C_CON_EN));
 328
 329                 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
 330                 /* For some reason we need to set the EN bit before the
 331                  * reset done bit gets set. */
 332                 timeout = jiffies + OMAP_I2C_TIMEOUT;
 333                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 334                 while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
 335                          SYSS_RESETDONE_MASK)) {
 336                         if (time_after(jiffies, timeout)) {
 337                                 dev_warn(dev->dev, "timeout waiting "
 338                                                 "for controller reset\n");
 339                                 return -ETIMEDOUT;
 340                         }
 341                         msleep(1);
 342                 }
 343
 344                 /* SYSC register is cleared by the reset; rewrite it */
 345                 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc);
 346
 347                 if (dev->rev > OMAP_I2C_REV_ON_3430_3530) {
 348                         /* Schedule I2C-bus monitoring on the next transfer */
 349                         dev->bb_valid = 0;
 350                 }
 351         }
 352
 353         return 0;
 354 }
 355
 356 static int omap_i2c_init(struct omap_i2c_dev *dev)
 357 {
 358         u16 psc = 0, scll = 0, sclh = 0;
 359         u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
 360         unsigned long fclk_rate = 12000000;
 361         unsigned long internal_clk = 0;
 362         struct clk *fclk;
 363
 364         if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
 365                 /*
 366                  * Enabling all wakup sources to stop I2C freezing on
 367                  * WFI instruction.
 368                  * REVISIT: Some wkup sources might not be needed.
 369                  */
 370                 dev->westate = OMAP_I2C_WE_ALL;
 371         }
 372
 373         if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
 374                 /*
 375                  * The I2C functional clock is the armxor_ck, so there's
 376                  * no need to get "armxor_ck" separately.  Now, if OMAP2420
 377                  * always returns 12MHz for the functional clock, we can
 378                  * do this bit unconditionally.
 379                  */
 380                 fclk = clk_get(dev->dev, "fck");
 381                 fclk_rate = clk_get_rate(fclk);
 382                 clk_put(fclk);
 383
 384                 /* TRM for 5912 says the I2C clock must be prescaled to be
 385                  * between 7 - 12 MHz. The XOR input clock is typically
 386                  * 12, 13 or 19.2 MHz. So we should have code that produces:
 387                  *
 388                  * XOR MHz      Divider         Prescaler
 389                  * 12           1               0
 390                  * 13           2               1
 391                  * 19.2         2               1
 392                  */
 393                 if (fclk_rate > 12000000)
 394                         psc = fclk_rate / 12000000;
 395         }
 396
 397         if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
 398
 399                 /*
 400                  * HSI2C controller internal clk rate should be 19.2 Mhz for
 401                  * HS and for all modes on 2430. On 34xx we can use lower rate
 402                  * to get longer filter period for better noise suppression.
 403                  * The filter is iclk (fclk for HS) period.
 404                  */
 405                 if (dev->speed > 400 ||
 406                                dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
 407                         internal_clk = 19200;
 408                 else if (dev->speed > 100)
 409                         internal_clk = 9600;
 410                 else
 411                         internal_clk = 4000;
 412                 fclk = clk_get(dev->dev, "fck");
 413                 fclk_rate = clk_get_rate(fclk) / 1000;
 414                 clk_put(fclk);
 415
 416                 /* Compute prescaler divisor */
 417                 psc = fclk_rate / internal_clk;
 418                 psc = psc - 1;
 419
 420                 /* If configured for High Speed */
 421                 if (dev->speed > 400) {
 422                         unsigned long scl;
 423
 424                         /* For first phase of HS mode */
 425                         scl = internal_clk / 400;
 426                         fsscll = scl - (scl / 3) - 7;
 427                         fssclh = (scl / 3) - 5;
 428
 429                         /* For second phase of HS mode */
 430                         scl = fclk_rate / dev->speed;
 431                         hsscll = scl - (scl / 3) - 7;
 432                         hssclh = (scl / 3) - 5;
 433                 } else if (dev->speed > 100) {
 434                         unsigned long scl;
 435
 436                         /* Fast mode */
 437                         scl = internal_clk / dev->speed;
 438                         fsscll = scl - (scl / 3) - 7;
 439                         fssclh = (scl / 3) - 5;
 440                 } else {
 441                         /* Standard mode */
 442                         fsscll = internal_clk / (dev->speed * 2) - 7;
 443                         fssclh = internal_clk / (dev->speed * 2) - 5;
 444                 }
 445                 scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
 446                 sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
 447         } else {
 448                 /* Program desired operating rate */
 449                 fclk_rate /= (psc + 1) * 1000;
 450                 if (psc > 2)
 451                         psc = 2;
 452                 scll = fclk_rate / (dev->speed * 2) - 7 + psc;
 453                 sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
 454         }
 455
 456         dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
 457                         OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
 458                         OMAP_I2C_IE_AL)  | ((dev->fifo_size) ?
 459                                 (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
 460
 461         dev->pscstate = psc;
 462         dev->scllstate = scll;
 463         dev->sclhstate = sclh;
 464
 465         if (dev->rev <= OMAP_I2C_REV_ON_3430_3530) {
 466                 /* Not implemented */
 467                 dev->bb_valid = 1;
 468         }
 469
 470         __omap_i2c_init(dev);
 471
 472         return 0;
 473 }
 474
 475 /*
 476  * Waiting on Bus Busy
 477  */
 478 static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
 479 {
 480         unsigned long timeout;
 481
 482         timeout = jiffies + OMAP_I2C_TIMEOUT;
 483         while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
 484                 if (time_after(jiffies, timeout)) {
 485                         dev_warn(dev->dev, "timeout waiting for bus ready\n");
 486                         return -ETIMEDOUT;
 487                 }
 488                 msleep(1);
 489         }
 490
 491         return 0;
 492 }
 493
 494 /*
 495  * Wait while BB-bit doesn't reflect the I2C bus state
 496  *
 497  * In a multimaster environment, after IP software reset, BB-bit value doesn't
 498  * correspond to the current bus state. It may happen what BB-bit will be 0,
 499  * while the bus is busy due to another I2C master activity.
 500  * Here are BB-bit values after reset:
 501  *     SDA   SCL   BB   NOTES
 502  *       0     0    0   1, 2
 503  *       1     0    0   1, 2
 504  *       0     1    1
 505  *       1     1    0   3
 506  * Later, if IP detect SDA=0 and SCL=1 (ACK) or SDA 1->0 while SCL=1 (START)
 507  * combinations on the bus, it set BB-bit to 1.
 508  * If IP detect SDA 0->1 while SCL=1 (STOP) combination on the bus,
 509  * it set BB-bit to 0 and BF to 1.
 510  * BB and BF bits correctly tracks the bus state while IP is suspended
 511  * BB bit became valid on the next FCLK clock after CON_EN bit set
 512  *
 513  * NOTES:
 514  * 1. Any transfer started when BB=0 and bus is busy wouldn't be
 515  *    completed by IP and results in controller timeout.
 516  * 2. Any transfer started when BB=0 and SCL=0 results in IP
 517  *    starting to drive SDA low. In that case IP corrupt data
 518  *    on the bus.
 519  * 3. Any transfer started in the middle of another master's transfer
 520  *    results in unpredictable results and data corruption
 521  */
 522 static int omap_i2c_wait_for_bb_valid(struct omap_i2c_dev *dev)
 523 {
 524         unsigned long bus_free_timeout = 0;
 525         unsigned long timeout;
 526         int bus_free = 0;
 527         u16 stat, systest;
 528
 529         if (dev->bb_valid)
 530                 return 0;
 531
 532         timeout = jiffies + OMAP_I2C_TIMEOUT;
 533         while (1) {
 534                 stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 535                 /*
 536                  * We will see BB or BF event in a case IP had detected any
 537                  * activity on the I2C bus. Now IP correctly tracks the bus
 538                  * state. BB-bit value is valid.
 539                  */
 540                 if (stat & (OMAP_I2C_STAT_BB | OMAP_I2C_STAT_BF))
 541                         break;
 542
 543                 /*
 544                  * Otherwise, we must look signals on the bus to make
 545                  * the right decision.
 546                  */
 547                 systest = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG);
 548                 if ((systest & OMAP_I2C_SYSTEST_SCL_I_FUNC) &&
 549                     (systest & OMAP_I2C_SYSTEST_SDA_I_FUNC)) {
 550                         if (!bus_free) {
 551                                 bus_free_timeout = jiffies +
 552                                         OMAP_I2C_BUS_FREE_TIMEOUT;
 553                                 bus_free = 1;
 554                         }
 555
 556                         /*
 557                          * SDA and SCL lines was high for 10 ms without bus
 558                          * activity detected. The bus is free. Consider
 559                          * BB-bit value is valid.
 560                          */
 561                         if (time_after(jiffies, bus_free_timeout))
 562                                 break;
 563                 } else {
 564                         bus_free = 0;
 565                 }
 566
 567                 if (time_after(jiffies, timeout)) {
 568                         dev_warn(dev->dev, "timeout waiting for bus ready\n");
 569                         return -ETIMEDOUT;
 570                 }
 571
 572                 msleep(1);
 573         }
 574
 575         dev->bb_valid = 1;
 576         return 0;
 577 }
 578
 579 static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
 580 {
 581         u16             buf;
 582
 583         if (dev->flags & OMAP_I2C_FLAG_NO_FIFO)
 584                 return;
 585
 586         /*
 587          * Set up notification threshold based on message size. We're doing
 588          * this to try and avoid draining feature as much as possible. Whenever
 589          * we have big messages to transfer (bigger than our total fifo size)
 590          * then we might use draining feature to transfer the remaining bytes.
 591          */
 592
 593         dev->threshold = clamp(size, (u8) 1, dev->fifo_size);
 594
 595         buf = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
 596
 597         if (is_rx) {
 598                 /* Clear RX Threshold */
 599                 buf &= ~(0x3f << 8);
 600                 buf |= ((dev->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR;
 601         } else {
 602                 /* Clear TX Threshold */
 603                 buf &= ~0x3f;
 604                 buf |= (dev->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR;
 605         }
 606
 607         omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
 608
 609         if (dev->rev < OMAP_I2C_REV_ON_3630)
 610                 dev->b_hw = 1; /* Enable hardware fixes */
 611
 612         /* calculate wakeup latency constraint for MPU */
 613         if (dev->set_mpu_wkup_lat != NULL)
 614                 dev->latency = (1000000 * dev->threshold) /
 615                         (1000 * dev->speed / 8);
 616 }
 617
 618 /*
 619  * Low level master read/write transaction.
 620  */
 621 static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 622                              struct i2c_msg *msg, int stop)
 623 {
 624         struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
 625         unsigned long timeout;
 626         u16 w;
 627
 628         dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
 629                 msg->addr, msg->len, msg->flags, stop);
 630
 631         if (msg->len == 0)
 632                 return -EINVAL;
 633
 634         dev->receiver = !!(msg->flags & I2C_M_RD);
 635         omap_i2c_resize_fifo(dev, msg->len, dev->receiver);
 636
 637         omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
 638
 639         /* REVISIT: Could the STB bit of I2C_CON be used with probing? */
 640         dev->buf = msg->buf;
 641         dev->buf_len = msg->len;
 642
 643         /* make sure writes to dev->buf_len are ordered */
 644         barrier();
 645
 646         omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
 647
 648         /* Clear the FIFO Buffers */
 649         w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
 650         w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
 651         omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
 652
 653         reinit_completion(&dev->cmd_complete);
 654         dev->cmd_err = 0;
 655
 656         w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
 657
 658         /* High speed configuration */
 659         if (dev->speed > 400)
 660                 w |= OMAP_I2C_CON_OPMODE_HS;
 661
 662         if (msg->flags & I2C_M_STOP)
 663                 stop = 1;
 664         if (msg->flags & I2C_M_TEN)
 665                 w |= OMAP_I2C_CON_XA;
 666         if (!(msg->flags & I2C_M_RD))
 667                 w |= OMAP_I2C_CON_TRX;
 668
 669         if (!dev->b_hw && stop)
 670                 w |= OMAP_I2C_CON_STP;
 671         /*
 672          * NOTE: STAT_BB bit could became 1 here if another master occupy
 673          * the bus. IP successfully complete transfer when the bus will be
 674          * free again (BB reset to 0).
 675          */
 676         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 677
 678         /*
 679          * Don't write stt and stp together on some hardware.
 680          */
 681         if (dev->b_hw && stop) {
 682                 unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
 683                 u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 684                 while (con & OMAP_I2C_CON_STT) {
 685                         con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 686
 687                         /* Let the user know if i2c is in a bad state */
 688                         if (time_after(jiffies, delay)) {
 689                                 dev_err(dev->dev, "controller timed out "
 690                                 "waiting for start condition to finish\n");
 691                                 return -ETIMEDOUT;
 692                         }
 693                         cpu_relax();
 694                 }
 695
 696                 w |= OMAP_I2C_CON_STP;
 697                 w &= ~OMAP_I2C_CON_STT;
 698                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 699         }
 700
 701         /*
 702          * REVISIT: We should abort the transfer on signals, but the bus goes
 703          * into arbitration and we're currently unable to recover from it.
 704          */
 705         timeout = wait_for_completion_timeout(&dev->cmd_complete,
 706                                                 OMAP_I2C_TIMEOUT);
 707         if (timeout == 0) {
 708                 dev_err(dev->dev, "controller timed out\n");
 709                 omap_i2c_reset(dev);
 710                 __omap_i2c_init(dev);
 711                 return -ETIMEDOUT;
 712         }
 713
 714         if (likely(!dev->cmd_err))
 715                 return 0;
 716
 717         /* We have an error */
 718         if (dev->cmd_err & (OMAP_I2C_STAT_ROVR | OMAP_I2C_STAT_XUDF)) {
 719                 omap_i2c_reset(dev);
 720                 __omap_i2c_init(dev);
 721                 return -EIO;
 722         }
 723
 724         if (dev->cmd_err & OMAP_I2C_STAT_AL)
 725                 return -EAGAIN;
 726
 727         if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
 728                 if (msg->flags & I2C_M_IGNORE_NAK)
 729                         return 0;
 730
 731                 w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
 732                 w |= OMAP_I2C_CON_STP;
 733                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
 734                 return -EREMOTEIO;
 735         }
 736         return -EIO;
 737 }
 738
 739
 740 /*
 741  * Prepare controller for a transaction and call omap_i2c_xfer_msg
 742  * to do the work during IRQ processing.
 743  */
 744 static int
 745 omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 746 {
 747         struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
 748         int i;
 749         int r;
 750
 751         r = pm_runtime_get_sync(dev->dev);
 752         if (r < 0)
 753                 goto out;
 754
 755         r = omap_i2c_wait_for_bb_valid(dev);
 756         if (r < 0)
 757                 goto out;
 758
 759         r = omap_i2c_wait_for_bb(dev);
 760         if (r < 0)
 761                 goto out;
 762
 763         if (dev->set_mpu_wkup_lat != NULL)
 764                 dev->set_mpu_wkup_lat(dev->dev, dev->latency);
 765
 766         for (i = 0; i < num; i++) {
 767                 r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
 768                 if (r != 0)
 769                         break;
 770         }
 771
 772         if (r == 0)
 773                 r = num;
 774
 775         omap_i2c_wait_for_bb(dev);
 776
 777         if (dev->set_mpu_wkup_lat != NULL)
 778                 dev->set_mpu_wkup_lat(dev->dev, -1);
 779
 780 out:
 781         pm_runtime_mark_last_busy(dev->dev);
 782         pm_runtime_put_autosuspend(dev->dev);
 783         return r;
 784 }
 785
 786 static u32
 787 omap_i2c_func(struct i2c_adapter *adap)
 788 {
 789         return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
 790                I2C_FUNC_PROTOCOL_MANGLING;
 791 }
 792
 793 static inline void
 794 omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
 795 {
 796         dev->cmd_err |= err;
 797         complete(&dev->cmd_complete);
 798 }
 799
 800 static inline void
 801 omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
 802 {
 803         omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
 804 }
 805
 806 static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
 807 {
 808         /*
 809          * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
 810          * Not applicable for OMAP4.
 811          * Under certain rare conditions, RDR could be set again
 812          * when the bus is busy, then ignore the interrupt and
 813          * clear the interrupt.
 814          */
 815         if (stat & OMAP_I2C_STAT_RDR) {
 816                 /* Step 1: If RDR is set, clear it */
 817                 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
 818
 819                 /* Step 2: */
 820                 if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
 821                                                 & OMAP_I2C_STAT_BB)) {
 822
 823                         /* Step 3: */
 824                         if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
 825                                                 & OMAP_I2C_STAT_RDR) {
 826                                 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
 827                                 dev_dbg(dev->dev, "RDR when bus is busy.\n");
 828                         }
 829
 830                 }
 831         }
 832 }
 833
 834 /* rev1 devices are apparently only on some 15xx */
 835 #ifdef CONFIG_ARCH_OMAP15XX
 836
 837 static irqreturn_t
 838 omap_i2c_omap1_isr(int this_irq, void *dev_id)
 839 {
 840         struct omap_i2c_dev *dev = dev_id;
 841         u16 iv, w;
 842
 843         if (pm_runtime_suspended(dev->dev))
 844                 return IRQ_NONE;
 845
 846         iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
 847         switch (iv) {
 848         case 0x00:      /* None */
 849                 break;
 850         case 0x01:      /* Arbitration lost */
 851                 dev_err(dev->dev, "Arbitration lost\n");
 852                 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
 853                 break;
 854         case 0x02:      /* No acknowledgement */
 855                 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
 856                 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
 857                 break;
 858         case 0x03:      /* Register access ready */
 859                 omap_i2c_complete_cmd(dev, 0);
 860                 break;
 861         case 0x04:      /* Receive data ready */
 862                 if (dev->buf_len) {
 863                         w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 864                         *dev->buf++ = w;
 865                         dev->buf_len--;
 866                         if (dev->buf_len) {
 867                                 *dev->buf++ = w >> 8;
 868                                 dev->buf_len--;
 869                         }
 870                 } else
 871                         dev_err(dev->dev, "RRDY IRQ while no data requested\n");
 872                 break;
 873         case 0x05:      /* Transmit data ready */
 874                 if (dev->buf_len) {
 875                         w = *dev->buf++;
 876                         dev->buf_len--;
 877                         if (dev->buf_len) {
 878                                 w |= *dev->buf++ << 8;
 879                                 dev->buf_len--;
 880                         }
 881                         omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 882                 } else
 883                         dev_err(dev->dev, "XRDY IRQ while no data to send\n");
 884                 break;
 885         default:
 886                 return IRQ_NONE;
 887         }
 888
 889         return IRQ_HANDLED;
 890 }
 891 #else
 892 #define omap_i2c_omap1_isr              NULL
 893 #endif
 894
 895 /*
 896  * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing
 897  * data to DATA_REG. Otherwise some data bytes can be lost while transferring
 898  * them from the memory to the I2C interface.
 899  */
 900 static int errata_omap3_i462(struct omap_i2c_dev *dev)
 901 {
 902         unsigned long timeout = 10000;
 903         u16 stat;
 904
 905         do {
 906                 stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 907                 if (stat & OMAP_I2C_STAT_XUDF)
 908                         break;
 909
 910                 if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
 911                         omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
 912                                                         OMAP_I2C_STAT_XDR));
 913                         if (stat & OMAP_I2C_STAT_NACK) {
 914                                 dev->cmd_err |= OMAP_I2C_STAT_NACK;
 915                                 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
 916                         }
 917
 918                         if (stat & OMAP_I2C_STAT_AL) {
 919                                 dev_err(dev->dev, "Arbitration lost\n");
 920                                 dev->cmd_err |= OMAP_I2C_STAT_AL;
 921                                 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
 922                         }
 923
 924                         return -EIO;
 925                 }
 926
 927                 cpu_relax();
 928         } while (--timeout);
 929
 930         if (!timeout) {
 931                 dev_err(dev->dev, "timeout waiting on XUDF bit\n");
 932                 return 0;
 933         }
 934
 935         return 0;
 936 }
 937
 938 static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
 939                 bool is_rdr)
 940 {
 941         u16             w;
 942
 943         while (num_bytes--) {
 944                 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 945                 *dev->buf++ = w;
 946                 dev->buf_len--;
 947
 948                 /*
 949                  * Data reg in 2430, omap3 and
 950                  * omap4 is 8 bit wide
 951                  */
 952                 if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
 953                         *dev->buf++ = w >> 8;
 954                         dev->buf_len--;
 955                 }
 956         }
 957 }
 958
 959 static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
 960                 bool is_xdr)
 961 {
 962         u16             w;
 963
 964         while (num_bytes--) {
 965                 w = *dev->buf++;
 966                 dev->buf_len--;
 967
 968                 /*
 969                  * Data reg in 2430, omap3 and
 970                  * omap4 is 8 bit wide
 971                  */
 972                 if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
 973                         w |= *dev->buf++ << 8;
 974                         dev->buf_len--;
 975                 }
 976
 977                 if (dev->errata & I2C_OMAP_ERRATA_I462) {
 978                         int ret;
 979
 980                         ret = errata_omap3_i462(dev);
 981                         if (ret < 0)
 982                                 return ret;
 983                 }
 984
 985                 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 986         }
 987
 988         return 0;
 989 }
 990
 991 static irqreturn_t
 992 omap_i2c_isr(int irq, void *dev_id)
 993 {
 994         struct omap_i2c_dev *dev = dev_id;
 995         irqreturn_t ret = IRQ_HANDLED;
 996         u16 mask;
 997         u16 stat;
 998
 999         spin_lock(&dev->lock);
1000         mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
1001         stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
1002
1003         if (stat & mask)
1004                 ret = IRQ_WAKE_THREAD;
1005
1006         spin_unlock(&dev->lock);
1007
1008         return ret;
1009 }
1010
1011 static irqreturn_t
1012 omap_i2c_isr_thread(int this_irq, void *dev_id)
1013 {
1014         struct omap_i2c_dev *dev = dev_id;
1015         unsigned long flags;
1016         u16 bits;
1017         u16 stat;
1018         int err = 0, count = 0;
1019
1020         spin_lock_irqsave(&dev->lock, flags);
1021         do {
1022                 bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
1023                 stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
1024                 stat &= bits;
1025
1026                 /* If we're in receiver mode, ignore XDR/XRDY */
1027                 if (dev->receiver)
1028                         stat &= ~(OMAP_I2C_STAT_XDR | OMAP_I2C_STAT_XRDY);
1029                 else
1030                         stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY);
1031
1032                 if (!stat) {
1033                         /* my work here is done */
1034                         goto out;
1035                 }
1036
1037                 dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
1038                 if (count++ == 100) {
1039                         dev_warn(dev->dev, "Too much work in one IRQ\n");
1040                         break;
1041                 }
1042
1043                 if (stat & OMAP_I2C_STAT_NACK) {
1044                         err |= OMAP_I2C_STAT_NACK;
1045                         omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
1046                 }
1047
1048                 if (stat & OMAP_I2C_STAT_AL) {
1049                         dev_err(dev->dev, "Arbitration lost\n");
1050                         err |= OMAP_I2C_STAT_AL;
1051                         omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
1052                 }
1053
1054                 /*
1055                  * ProDB0017052: Clear ARDY bit twice
1056                  */
1057                 if (stat & OMAP_I2C_STAT_ARDY)
1058                         omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ARDY);
1059
1060                 if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
1061                                         OMAP_I2C_STAT_AL)) {
1062                         omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
1063                                                 OMAP_I2C_STAT_RDR |
1064                                                 OMAP_I2C_STAT_XRDY |
1065                                                 OMAP_I2C_STAT_XDR |
1066                                                 OMAP_I2C_STAT_ARDY));
1067                         break;
1068                 }
1069
1070                 if (stat & OMAP_I2C_STAT_RDR) {
1071                         u8 num_bytes = 1;
1072
1073                         if (dev->fifo_size)
1074                                 num_bytes = dev->buf_len;
1075
1076                         if (dev->errata & I2C_OMAP_ERRATA_I207) {
1077                                 i2c_omap_errata_i207(dev, stat);
1078                                 num_bytes = (omap_i2c_read_reg(dev,
1079                                         OMAP_I2C_BUFSTAT_REG) >> 8) & 0x3F;
1080                         }
1081
1082                         omap_i2c_receive_data(dev, num_bytes, true);
1083                         omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
1084                         continue;
1085                 }
1086
1087                 if (stat & OMAP_I2C_STAT_RRDY) {
1088                         u8 num_bytes = 1;
1089
1090                         if (dev->threshold)
1091                                 num_bytes = dev->threshold;
1092
1093                         omap_i2c_receive_data(dev, num_bytes, false);
1094                         omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
1095                         continue;
1096                 }
1097
1098                 if (stat & OMAP_I2C_STAT_XDR) {
1099                         u8 num_bytes = 1;
1100                         int ret;
1101
1102                         if (dev->fifo_size)
1103                                 num_bytes = dev->buf_len;
1104
1105                         ret = omap_i2c_transmit_data(dev, num_bytes, true);
1106                         if (ret < 0)
1107                                 break;
1108
1109                         omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
1110                         continue;
1111                 }
1112
1113                 if (stat & OMAP_I2C_STAT_XRDY) {
1114                         u8 num_bytes = 1;
1115                         int ret;
1116
1117                         if (dev->threshold)
1118                                 num_bytes = dev->threshold;
1119
1120                         ret = omap_i2c_transmit_data(dev, num_bytes, false);
1121                         if (ret < 0)
1122                                 break;
1123
1124                         omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
1125                         continue;
1126                 }
1127
1128                 if (stat & OMAP_I2C_STAT_ROVR) {
1129                         dev_err(dev->dev, "Receive overrun\n");
1130                         err |= OMAP_I2C_STAT_ROVR;
1131                         omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
1132                         break;
1133                 }
1134
1135                 if (stat & OMAP_I2C_STAT_XUDF) {
1136                         dev_err(dev->dev, "Transmit underflow\n");
1137                         err |= OMAP_I2C_STAT_XUDF;
1138                         omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
1139                         break;
1140                 }
1141         } while (stat);
1142
1143         omap_i2c_complete_cmd(dev, err);
1144
1145 out:
1146         spin_unlock_irqrestore(&dev->lock, flags);
1147
1148         return IRQ_HANDLED;
1149 }
1150
1151 static const struct i2c_algorithm omap_i2c_algo = {
1152         .master_xfer    = omap_i2c_xfer,
1153         .functionality  = omap_i2c_func,
1154 };
1155
1156 #ifdef CONFIG_OF
1157 static struct omap_i2c_bus_platform_data omap2420_pdata = {
1158         .rev = OMAP_I2C_IP_VERSION_1,
1159         .flags = OMAP_I2C_FLAG_NO_FIFO |
1160                         OMAP_I2C_FLAG_SIMPLE_CLOCK |
1161                         OMAP_I2C_FLAG_16BIT_DATA_REG |
1162                         OMAP_I2C_FLAG_BUS_SHIFT_2,
1163 };
1164
1165 static struct omap_i2c_bus_platform_data omap2430_pdata = {
1166         .rev = OMAP_I2C_IP_VERSION_1,
1167         .flags = OMAP_I2C_FLAG_BUS_SHIFT_2 |
1168                         OMAP_I2C_FLAG_FORCE_19200_INT_CLK,
1169 };
1170
1171 static struct omap_i2c_bus_platform_data omap3_pdata = {
1172         .rev = OMAP_I2C_IP_VERSION_1,
1173         .flags = OMAP_I2C_FLAG_BUS_SHIFT_2,
1174 };
1175
1176 static struct omap_i2c_bus_platform_data omap4_pdata = {
1177         .rev = OMAP_I2C_IP_VERSION_2,
1178 };
1179
1180 static const struct of_device_id omap_i2c_of_match[] = {
1181         {
1182                 .compatible = "ti,omap4-i2c",
1183                 .data = &omap4_pdata,
1184         },
1185         {
1186                 .compatible = "ti,omap3-i2c",
1187                 .data = &omap3_pdata,
1188         },
1189         {
1190                 .compatible = "ti,omap2430-i2c",
1191                 .data = &omap2430_pdata,
1192         },
1193         {
1194                 .compatible = "ti,omap2420-i2c",
1195                 .data = &omap2420_pdata,
1196         },
1197         { },
1198 };
1199 MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
1200 #endif
1201
1202 #define OMAP_I2C_SCHEME(rev)            ((rev & 0xc000) >> 14)
1203
1204 #define OMAP_I2C_REV_SCHEME_0_MAJOR(rev) (rev >> 4)
1205 #define OMAP_I2C_REV_SCHEME_0_MINOR(rev) (rev & 0xf)
1206
1207 #define OMAP_I2C_REV_SCHEME_1_MAJOR(rev) ((rev & 0x0700) >> 7)
1208 #define OMAP_I2C_REV_SCHEME_1_MINOR(rev) (rev & 0x1f)
1209 #define OMAP_I2C_SCHEME_0               0
1210 #define OMAP_I2C_SCHEME_1               1
1211
1212 static int
1213 omap_i2c_probe(struct platform_device *pdev)
1214 {
1215         struct omap_i2c_dev     *dev;
1216         struct i2c_adapter      *adap;
1217         struct resource         *mem;
1218         const struct omap_i2c_bus_platform_data *pdata =
1219                 dev_get_platdata(&pdev->dev);
1220         struct device_node      *node = pdev->dev.of_node;
1221         const struct of_device_id *match;
1222         int irq;
1223         int r;
1224         u32 rev;
1225         u16 minor, major;
1226
1227         irq = platform_get_irq(pdev, 0);
1228         if (irq < 0) {
1229                 dev_err(&pdev->dev, "no irq resource?\n");
1230                 return irq;
1231         }
1232
1233         dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
1234         if (!dev)
1235                 return -ENOMEM;
1236
1237         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1238         dev->base = devm_ioremap_resource(&pdev->dev, mem);
1239         if (IS_ERR(dev->base))
1240                 return PTR_ERR(dev->base);
1241
1242         match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
1243         if (match) {
1244                 u32 freq = 100000; /* default to 100000 Hz */
1245
1246                 pdata = match->data;
1247                 dev->flags = pdata->flags;
1248
1249                 of_property_read_u32(node, "clock-frequency", &freq);
1250                 /* convert DT freq value in Hz into kHz for speed */
1251                 dev->speed = freq / 1000;
1252         } else if (pdata != NULL) {
1253                 dev->speed = pdata->clkrate;
1254                 dev->flags = pdata->flags;
1255                 dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
1256         }
1257
1258         dev->dev = &pdev->dev;
1259         dev->irq = irq;
1260
1261         spin_lock_init(&dev->lock);
1262
1263         platform_set_drvdata(pdev, dev);
1264         init_completion(&dev->cmd_complete);
1265
1266         dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
1267
1268         pm_runtime_enable(dev->dev);
1269         pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT);
1270         pm_runtime_use_autosuspend(dev->dev);
1271
1272         r = pm_runtime_get_sync(dev->dev);
1273         if (r < 0)
1274                 goto err_free_mem;
1275
1276         /*
1277          * Read the Rev hi bit-[15:14] ie scheme this is 1 indicates ver2.
1278          * On omap1/3/2 Offset 4 is IE Reg the bit [15:14] is 0 at reset.
1279          * Also since the omap_i2c_read_reg uses reg_map_ip_* a
1280          * readw_relaxed is done.
1281          */
1282         rev = readw_relaxed(dev->base + 0x04);
1283
1284         dev->scheme = OMAP_I2C_SCHEME(rev);
1285         switch (dev->scheme) {
1286         case OMAP_I2C_SCHEME_0:
1287                 dev->regs = (u8 *)reg_map_ip_v1;
1288                 dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG);
1289                 minor = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
1290                 major = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
1291                 break;
1292         case OMAP_I2C_SCHEME_1:
1293                 /* FALLTHROUGH */
1294         default:
1295                 dev->regs = (u8 *)reg_map_ip_v2;
1296                 rev = (rev << 16) |
1297                         omap_i2c_read_reg(dev, OMAP_I2C_IP_V2_REVNB_LO);
1298                 minor = OMAP_I2C_REV_SCHEME_1_MINOR(rev);
1299                 major = OMAP_I2C_REV_SCHEME_1_MAJOR(rev);
1300                 dev->rev = rev;
1301         }
1302
1303         dev->errata = 0;
1304
1305         if (dev->rev >= OMAP_I2C_REV_ON_2430 &&
1306                         dev->rev < OMAP_I2C_REV_ON_4430_PLUS)
1307                 dev->errata |= I2C_OMAP_ERRATA_I207;
1308
1309         if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
1310                 dev->errata |= I2C_OMAP_ERRATA_I462;
1311
1312         if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
1313                 u16 s;
1314
1315                 /* Set up the fifo size - Get total size */
1316                 s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
1317                 dev->fifo_size = 0x8 << s;
1318
1319                 /*
1320                  * Set up notification threshold as half the total available
1321                  * size. This is to ensure that we can handle the status on int
1322                  * call back latencies.
1323                  */
1324
1325                 dev->fifo_size = (dev->fifo_size / 2);
1326
1327                 if (dev->rev < OMAP_I2C_REV_ON_3630)
1328                         dev->b_hw = 1; /* Enable hardware fixes */
1329
1330                 /* calculate wakeup latency constraint for MPU */
1331                 if (dev->set_mpu_wkup_lat != NULL)
1332                         dev->latency = (1000000 * dev->fifo_size) /
1333                                        (1000 * dev->speed / 8);
1334         }
1335
1336         /* reset ASAP, clearing any IRQs */
1337         omap_i2c_init(dev);
1338
1339         if (dev->rev < OMAP_I2C_OMAP1_REV_2)
1340                 r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr,
1341                                 IRQF_NO_SUSPEND, pdev->name, dev);
1342         else
1343                 r = devm_request_threaded_irq(&pdev->dev, dev->irq,
1344                                 omap_i2c_isr, omap_i2c_isr_thread,
1345                                 IRQF_NO_SUSPEND | IRQF_ONESHOT,
1346                                 pdev->name, dev);
1347
1348         if (r) {
1349                 dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
1350                 goto err_unuse_clocks;
1351         }
1352
1353         adap = &dev->adapter;
1354         i2c_set_adapdata(adap, dev);
1355         adap->owner = THIS_MODULE;
1356         adap->class = I2C_CLASS_DEPRECATED;
1357         strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
1358         adap->algo = &omap_i2c_algo;
1359         adap->dev.parent = &pdev->dev;
1360         adap->dev.of_node = pdev->dev.of_node;
1361
1362         /* i2c device drivers may be active on return from add_adapter() */
1363         adap->nr = pdev->id;
1364         r = i2c_add_numbered_adapter(adap);
1365         if (r) {
1366                 dev_err(dev->dev, "failure adding adapter\n");
1367                 goto err_unuse_clocks;
1368         }
1369
1370         dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr,
1371                  major, minor, dev->speed);
1372
1373         pm_runtime_mark_last_busy(dev->dev);
1374         pm_runtime_put_autosuspend(dev->dev);
1375
1376         return 0;
1377
1378 err_unuse_clocks:
1379         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1380         pm_runtime_put(dev->dev);
1381         pm_runtime_disable(&pdev->dev);
1382 err_free_mem:
1383
1384         return r;
1385 }
1386
1387 static int omap_i2c_remove(struct platform_device *pdev)
1388 {
1389         struct omap_i2c_dev     *dev = platform_get_drvdata(pdev);
1390         int ret;
1391
1392         i2c_del_adapter(&dev->adapter);
1393         ret = pm_runtime_get_sync(&pdev->dev);
1394         if (ret < 0)
1395                 return ret;
1396
1397         omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1398         pm_runtime_put(&pdev->dev);
1399         pm_runtime_disable(&pdev->dev);
1400         return 0;
1401 }
1402
1403 #ifdef CONFIG_PM
1404 static int omap_i2c_runtime_suspend(struct device *dev)
1405 {
1406         struct platform_device *pdev = to_platform_device(dev);
1407         struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1408
1409         _dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
1410
1411         if (_dev->scheme == OMAP_I2C_SCHEME_0)
1412                 omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
1413         else
1414                 omap_i2c_write_reg(_dev, OMAP_I2C_IP_V2_IRQENABLE_CLR,
1415                                    OMAP_I2C_IP_V2_INTERRUPTS_MASK);
1416
1417         if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
1418                 omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
1419         } else {
1420                 omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
1421
1422                 /* Flush posted write */
1423                 omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
1424         }
1425
1426         return 0;
1427 }
1428
1429 static int omap_i2c_runtime_resume(struct device *dev)
1430 {
1431         struct platform_device *pdev = to_platform_device(dev);
1432         struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1433
1434         if (!_dev->regs)
1435                 return 0;
1436
1437         __omap_i2c_init(_dev);
1438
1439         return 0;
1440 }
1441
1442 static struct dev_pm_ops omap_i2c_pm_ops = {
1443         SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
1444                            omap_i2c_runtime_resume, NULL)
1445 };
1446 #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
1447 #else
1448 #define OMAP_I2C_PM_OPS NULL
1449 #endif /* CONFIG_PM */
1450
1451 static struct platform_driver omap_i2c_driver = {
1452         .probe          = omap_i2c_probe,
1453         .remove         = omap_i2c_remove,
1454         .driver         = {
1455                 .name   = "omap_i2c",
1456                 .pm     = OMAP_I2C_PM_OPS,
1457                 .of_match_table = of_match_ptr(omap_i2c_of_match),
1458         },
1459 };
1460
1461 /* I2C may be needed to bring up other drivers */
1462 static int __init
1463 omap_i2c_init_driver(void)
1464 {
1465         return platform_driver_register(&omap_i2c_driver);
1466 }
1467 subsys_initcall(omap_i2c_init_driver);
1468
1469 static void __exit omap_i2c_exit_driver(void)
1470 {
1471         platform_driver_unregister(&omap_i2c_driver);
1472 }
1473 module_exit(omap_i2c_exit_driver);
1474
1475 MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1476 MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1477 MODULE_LICENSE("GPL");
1478 MODULE_ALIAS("platform:omap_i2c");