drivers/i2c/busses/i2c-pnx.c

   1 /*
   2  * Provides I2C support for Philips PNX010x/PNX4008 boards.
   3  *
   4  * Authors: Dennis Kovalev <dkovalev@ru.mvista.com>
   5  *          Vitaly Wool <vwool@ru.mvista.com>
   6  *
   7  * 2004-2006 (c) MontaVista Software, Inc. This file is licensed under
   8  * the terms of the GNU General Public License version 2. This program
   9  * is licensed "as is" without any warranty of any kind, whether express
  10  * or implied.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/ioport.h>
  16 #include <linux/delay.h>
  17 #include <linux/i2c.h>
  18 #include <linux/timer.h>
  19 #include <linux/completion.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/i2c-pnx.h>
  22 #include <asm/hardware.h>
  23 #include <asm/irq.h>
  24 #include <asm/uaccess.h>
  25
  26 #define I2C_PNX_TIMEOUT         10 /* msec */
  27 #define I2C_PNX_SPEED_KHZ       100
  28 #define I2C_PNX_REGION_SIZE     0x100
  29 #define PNX_DEFAULT_FREQ        13 /* MHz */
  30
  31 static inline int wait_timeout(long timeout, struct i2c_pnx_algo_data *data)
  32 {
  33         while (timeout > 0 &&
  34                         (ioread32(I2C_REG_STS(data)) & mstatus_active)) {
  35                 mdelay(1);
  36                 timeout--;
  37         }
  38         return (timeout <= 0);
  39 }
  40
  41 static inline int wait_reset(long timeout, struct i2c_pnx_algo_data *data)
  42 {
  43         while (timeout > 0 &&
  44                         (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) {
  45                 mdelay(1);
  46                 timeout--;
  47         }
  48         return (timeout <= 0);
  49 }
  50
  51 static inline void i2c_pnx_arm_timer(struct i2c_adapter *adap)
  52 {
  53         struct i2c_pnx_algo_data *data = adap->algo_data;
  54         struct timer_list *timer = &data->mif.timer;
  55         int expires = I2C_PNX_TIMEOUT / (1000 / HZ);
  56
  57         del_timer_sync(timer);
  58
  59         dev_dbg(&adap->dev, "Timer armed at %lu plus %u jiffies.\n",
  60                 jiffies, expires);
  61
  62         timer->expires = jiffies + expires;
  63         timer->data = (unsigned long)adap;
  64
  65         add_timer(timer);
  66 }
  67
  68 /**
  69  * i2c_pnx_start - start a device
  70  * @slave_addr:         slave address
  71  * @adap:               pointer to adapter structure
  72  *
  73  * Generate a START signal in the desired mode.
  74  */
  75 static int i2c_pnx_start(unsigned char slave_addr, struct i2c_adapter *adap)
  76 {
  77         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
  78
  79         dev_dbg(&adap->dev, "%s(): addr 0x%x mode %d\n", __FUNCTION__,
  80                 slave_addr, alg_data->mif.mode);
  81
  82         /* Check for 7 bit slave addresses only */
  83         if (slave_addr & ~0x7f) {
  84                 dev_err(&adap->dev, "%s: Invalid slave address %x. "
  85                        "Only 7-bit addresses are supported\n",
  86                        adap->name, slave_addr);
  87                 return -EINVAL;
  88         }
  89
  90         /* First, make sure bus is idle */
  91         if (wait_timeout(I2C_PNX_TIMEOUT, alg_data)) {
  92                 /* Somebody else is monopolizing the bus */
  93                 dev_err(&adap->dev, "%s: Bus busy. Slave addr = %02x, "
  94                        "cntrl = %x, stat = %x\n",
  95                        adap->name, slave_addr,
  96                        ioread32(I2C_REG_CTL(alg_data)),
  97                        ioread32(I2C_REG_STS(alg_data)));
  98                 return -EBUSY;
  99         } else if (ioread32(I2C_REG_STS(alg_data)) & mstatus_afi) {
 100                 /* Sorry, we lost the bus */
 101                 dev_err(&adap->dev, "%s: Arbitration failure. "
 102                        "Slave addr = %02x\n", adap->name, slave_addr);
 103                 return -EIO;
 104         }
 105
 106         /*
 107          * OK, I2C is enabled and we have the bus.
 108          * Clear the current TDI and AFI status flags.
 109          */
 110         iowrite32(ioread32(I2C_REG_STS(alg_data)) | mstatus_tdi | mstatus_afi,
 111                   I2C_REG_STS(alg_data));
 112
 113         dev_dbg(&adap->dev, "%s(): sending %#x\n", __FUNCTION__,
 114                 (slave_addr << 1) | start_bit | alg_data->mif.mode);
 115
 116         /* Write the slave address, START bit and R/W bit */
 117         iowrite32((slave_addr << 1) | start_bit | alg_data->mif.mode,
 118                   I2C_REG_TX(alg_data));
 119
 120         dev_dbg(&adap->dev, "%s(): exit\n", __FUNCTION__);
 121
 122         return 0;
 123 }
 124
 125 /**
 126  * i2c_pnx_stop - stop a device
 127  * @adap:               pointer to I2C adapter structure
 128  *
 129  * Generate a STOP signal to terminate the master transaction.
 130  */
 131 static void i2c_pnx_stop(struct i2c_adapter *adap)
 132 {
 133         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
 134         /* Only 1 msec max timeout due to interrupt context */
 135         long timeout = 1000;
 136
 137         dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n",
 138                 __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
 139
 140         /* Write a STOP bit to TX FIFO */
 141         iowrite32(0xff | stop_bit, I2C_REG_TX(alg_data));
 142
 143         /* Wait until the STOP is seen. */
 144         while (timeout > 0 &&
 145                (ioread32(I2C_REG_STS(alg_data)) & mstatus_active)) {
 146                 /* may be called from interrupt context */
 147                 udelay(1);
 148                 timeout--;
 149         }
 150
 151         dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n",
 152                 __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
 153 }
 154
 155 /**
 156  * i2c_pnx_master_xmit - transmit data to slave
 157  * @adap:               pointer to I2C adapter structure
 158  *
 159  * Sends one byte of data to the slave
 160  */
 161 static int i2c_pnx_master_xmit(struct i2c_adapter *adap)
 162 {
 163         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
 164         u32 val;
 165
 166         dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n",
 167                 __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
 168
 169         if (alg_data->mif.len > 0) {
 170                 /* We still have something to talk about... */
 171                 val = *alg_data->mif.buf++;
 172
 173                 if (alg_data->mif.len == 1) {
 174                         val |= stop_bit;
 175                         if (!alg_data->last)
 176                                 val |= start_bit;
 177                 }
 178
 179                 alg_data->mif.len--;
 180                 iowrite32(val, I2C_REG_TX(alg_data));
 181
 182                 dev_dbg(&adap->dev, "%s(): xmit %#x [%d]\n", __FUNCTION__,
 183                         val, alg_data->mif.len + 1);
 184
 185                 if (alg_data->mif.len == 0) {
 186                         if (alg_data->last) {
 187                                 /* Wait until the STOP is seen. */
 188                                 if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
 189                                         dev_err(&adap->dev, "The bus is still "
 190                                                 "active after timeout\n");
 191                         }
 192                         /* Disable master interrupts */
 193                         iowrite32(ioread32(I2C_REG_CTL(alg_data)) &
 194                                 ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie),
 195                                   I2C_REG_CTL(alg_data));
 196
 197                         del_timer_sync(&alg_data->mif.timer);
 198
 199                         dev_dbg(&adap->dev, "%s(): Waking up xfer routine.\n",
 200                                 __FUNCTION__);
 201
 202                         complete(&alg_data->mif.complete);
 203                 }
 204         } else if (alg_data->mif.len == 0) {
 205                 /* zero-sized transfer */
 206                 i2c_pnx_stop(adap);
 207
 208                 /* Disable master interrupts. */
 209                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) &
 210                         ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie),
 211                           I2C_REG_CTL(alg_data));
 212
 213                 /* Stop timer. */
 214                 del_timer_sync(&alg_data->mif.timer);
 215                 dev_dbg(&adap->dev, "%s(): Waking up xfer routine after "
 216                         "zero-xfer.\n", __FUNCTION__);
 217
 218                 complete(&alg_data->mif.complete);
 219         }
 220
 221         dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n",
 222                 __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
 223
 224         return 0;
 225 }
 226
 227 /**
 228  * i2c_pnx_master_rcv - receive data from slave
 229  * @adap:               pointer to I2C adapter structure
 230  *
 231  * Reads one byte data from the slave
 232  */
 233 static int i2c_pnx_master_rcv(struct i2c_adapter *adap)
 234 {
 235         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
 236         unsigned int val = 0;
 237         u32 ctl = 0;
 238
 239         dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n",
 240                 __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
 241
 242         /* Check, whether there is already data,
 243          * or we didn't 'ask' for it yet.
 244          */
 245         if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) {
 246                 dev_dbg(&adap->dev, "%s(): Write dummy data to fill "
 247                         "Rx-fifo...\n", __FUNCTION__);
 248
 249                 if (alg_data->mif.len == 1) {
 250                         /* Last byte, do not acknowledge next rcv. */
 251                         val |= stop_bit;
 252                         if (!alg_data->last)
 253                                 val |= start_bit;
 254
 255                         /*
 256                          * Enable interrupt RFDAIE (data in Rx fifo),
 257                          * and disable DRMIE (need data for Tx)
 258                          */
 259                         ctl = ioread32(I2C_REG_CTL(alg_data));
 260                         ctl |= mcntrl_rffie | mcntrl_daie;
 261                         ctl &= ~mcntrl_drmie;
 262                         iowrite32(ctl, I2C_REG_CTL(alg_data));
 263                 }
 264
 265                 /*
 266                  * Now we'll 'ask' for data:
 267                  * For each byte we want to receive, we must
 268                  * write a (dummy) byte to the Tx-FIFO.
 269                  */
 270                 iowrite32(val, I2C_REG_TX(alg_data));
 271
 272                 return 0;
 273         }
 274
 275         /* Handle data. */
 276         if (alg_data->mif.len > 0) {
 277                 val = ioread32(I2C_REG_RX(alg_data));
 278                 *alg_data->mif.buf++ = (u8) (val & 0xff);
 279                 dev_dbg(&adap->dev, "%s(): rcv 0x%x [%d]\n", __FUNCTION__, val,
 280                         alg_data->mif.len);
 281
 282                 alg_data->mif.len--;
 283                 if (alg_data->mif.len == 0) {
 284                         if (alg_data->last)
 285                                 /* Wait until the STOP is seen. */
 286                                 if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
 287                                         dev_err(&adap->dev, "The bus is still "
 288                                                 "active after timeout\n");
 289
 290                         /* Disable master interrupts */
 291                         ctl = ioread32(I2C_REG_CTL(alg_data));
 292                         ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
 293                                  mcntrl_drmie | mcntrl_daie);
 294                         iowrite32(ctl, I2C_REG_CTL(alg_data));
 295
 296                         /* Kill timer. */
 297                         del_timer_sync(&alg_data->mif.timer);
 298                         complete(&alg_data->mif.complete);
 299                 }
 300         }
 301
 302         dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n",
 303                 __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
 304
 305         return 0;
 306 }
 307
 308 static irqreturn_t i2c_pnx_interrupt(int irq, void *dev_id)
 309 {
 310         u32 stat, ctl;
 311         struct i2c_adapter *adap = dev_id;
 312         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
 313
 314         dev_dbg(&adap->dev, "%s(): mstat = %x mctrl = %x, mode = %d\n",
 315                 __FUNCTION__,
 316                 ioread32(I2C_REG_STS(alg_data)),
 317                 ioread32(I2C_REG_CTL(alg_data)),
 318                 alg_data->mif.mode);
 319         stat = ioread32(I2C_REG_STS(alg_data));
 320
 321         /* let's see what kind of event this is */
 322         if (stat & mstatus_afi) {
 323                 /* We lost arbitration in the midst of a transfer */
 324                 alg_data->mif.ret = -EIO;
 325
 326                 /* Disable master interrupts. */
 327                 ctl = ioread32(I2C_REG_CTL(alg_data));
 328                 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
 329                          mcntrl_drmie);
 330                 iowrite32(ctl, I2C_REG_CTL(alg_data));
 331
 332                 /* Stop timer, to prevent timeout. */
 333                 del_timer_sync(&alg_data->mif.timer);
 334                 complete(&alg_data->mif.complete);
 335         } else if (stat & mstatus_nai) {
 336                 /* Slave did not acknowledge, generate a STOP */
 337                 dev_dbg(&adap->dev, "%s(): "
 338                         "Slave did not acknowledge, generating a STOP.\n",
 339                         __FUNCTION__);
 340                 i2c_pnx_stop(adap);
 341
 342                 /* Disable master interrupts. */
 343                 ctl = ioread32(I2C_REG_CTL(alg_data));
 344                 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
 345                          mcntrl_drmie);
 346                 iowrite32(ctl, I2C_REG_CTL(alg_data));
 347
 348                 /* Our return value. */
 349                 alg_data->mif.ret = -EIO;
 350
 351                 /* Stop timer, to prevent timeout. */
 352                 del_timer_sync(&alg_data->mif.timer);
 353                 complete(&alg_data->mif.complete);
 354         } else {
 355                 /*
 356                  * Two options:
 357                  * - Master Tx needs data.
 358                  * - There is data in the Rx-fifo
 359                  * The latter is only the case if we have requested for data,
 360                  * via a dummy write. (See 'i2c_pnx_master_rcv'.)
 361                  * We therefore check, as a sanity check, whether that interrupt
 362                  * has been enabled.
 363                  */
 364                 if ((stat & mstatus_drmi) || !(stat & mstatus_rfe)) {
 365                         if (alg_data->mif.mode == I2C_SMBUS_WRITE) {
 366                                 i2c_pnx_master_xmit(adap);
 367                         } else if (alg_data->mif.mode == I2C_SMBUS_READ) {
 368                                 i2c_pnx_master_rcv(adap);
 369                         }
 370                 }
 371         }
 372
 373         /* Clear TDI and AFI bits */
 374         stat = ioread32(I2C_REG_STS(alg_data));
 375         iowrite32(stat | mstatus_tdi | mstatus_afi, I2C_REG_STS(alg_data));
 376
 377         dev_dbg(&adap->dev, "%s(): exiting, stat = %x ctrl = %x.\n",
 378                  __FUNCTION__, ioread32(I2C_REG_STS(alg_data)),
 379                  ioread32(I2C_REG_CTL(alg_data)));
 380
 381         return IRQ_HANDLED;
 382 }
 383
 384 static void i2c_pnx_timeout(unsigned long data)
 385 {
 386         struct i2c_adapter *adap = (struct i2c_adapter *)data;
 387         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
 388         u32 ctl;
 389
 390         dev_err(&adap->dev, "Master timed out. stat = %04x, cntrl = %04x. "
 391                "Resetting master...\n",
 392                ioread32(I2C_REG_STS(alg_data)),
 393                ioread32(I2C_REG_CTL(alg_data)));
 394
 395         /* Reset master and disable interrupts */
 396         ctl = ioread32(I2C_REG_CTL(alg_data));
 397         ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | mcntrl_drmie);
 398         iowrite32(ctl, I2C_REG_CTL(alg_data));
 399
 400         ctl |= mcntrl_reset;
 401         iowrite32(ctl, I2C_REG_CTL(alg_data));
 402         wait_reset(I2C_PNX_TIMEOUT, alg_data);
 403         alg_data->mif.ret = -EIO;
 404         complete(&alg_data->mif.complete);
 405 }
 406
 407 static inline void bus_reset_if_active(struct i2c_adapter *adap)
 408 {
 409         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
 410         u32 stat;
 411
 412         if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_active) {
 413                 dev_err(&adap->dev,
 414                         "%s: Bus is still active after xfer. Reset it...\n",
 415                        adap->name);
 416                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
 417                           I2C_REG_CTL(alg_data));
 418                 wait_reset(I2C_PNX_TIMEOUT, alg_data);
 419         } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) {
 420                 /* If there is data in the fifo's after transfer,
 421                  * flush fifo's by reset.
 422                  */
 423                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
 424                           I2C_REG_CTL(alg_data));
 425                 wait_reset(I2C_PNX_TIMEOUT, alg_data);
 426         } else if (stat & mstatus_nai) {
 427                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
 428                           I2C_REG_CTL(alg_data));
 429                 wait_reset(I2C_PNX_TIMEOUT, alg_data);
 430         }
 431 }
 432
 433 /**
 434  * i2c_pnx_xfer - generic transfer entry point
 435  * @adap:               pointer to I2C adapter structure
 436  * @msgs:               array of messages
 437  * @num:                number of messages
 438  *
 439  * Initiates the transfer
 440  */
 441 static int
 442 i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
 443 {
 444         struct i2c_msg *pmsg;
 445         int rc = 0, completed = 0, i;
 446         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
 447         u32 stat = ioread32(I2C_REG_STS(alg_data));
 448
 449         dev_dbg(&adap->dev, "%s(): entering: %d messages, stat = %04x.\n",
 450                 __FUNCTION__, num, ioread32(I2C_REG_STS(alg_data)));
 451
 452         bus_reset_if_active(adap);
 453
 454         /* Process transactions in a loop. */
 455         for (i = 0; rc >= 0 && i < num; i++) {
 456                 u8 addr;
 457
 458                 pmsg = &msgs[i];
 459                 addr = pmsg->addr;
 460
 461                 if (pmsg->flags & I2C_M_TEN) {
 462                         dev_err(&adap->dev,
 463                                 "%s: 10 bits addr not supported!\n",
 464                                 adap->name);
 465                         rc = -EINVAL;
 466                         break;
 467                 }
 468
 469                 alg_data->mif.buf = pmsg->buf;
 470                 alg_data->mif.len = pmsg->len;
 471                 alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ?
 472                         I2C_SMBUS_READ : I2C_SMBUS_WRITE;
 473                 alg_data->mif.ret = 0;
 474                 alg_data->last = (i == num - 1);
 475
 476                 dev_dbg(&adap->dev, "%s(): mode %d, %d bytes\n", __FUNCTION__,
 477                         alg_data->mif.mode,
 478                         alg_data->mif.len);
 479
 480                 i2c_pnx_arm_timer(adap);
 481
 482                 /* initialize the completion var */
 483                 init_completion(&alg_data->mif.complete);
 484
 485                 /* Enable master interrupt */
 486                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_afie |
 487                                 mcntrl_naie | mcntrl_drmie,
 488                           I2C_REG_CTL(alg_data));
 489
 490                 /* Put start-code and slave-address on the bus. */
 491                 rc = i2c_pnx_start(addr, adap);
 492                 if (rc < 0)
 493                         break;
 494
 495                 /* Wait for completion */
 496                 wait_for_completion(&alg_data->mif.complete);
 497
 498                 if (!(rc = alg_data->mif.ret))
 499                         completed++;
 500                 dev_dbg(&adap->dev, "%s(): Complete, return code = %d.\n",
 501                         __FUNCTION__, rc);
 502
 503                 /* Clear TDI and AFI bits in case they are set. */
 504                 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_tdi) {
 505                         dev_dbg(&adap->dev,
 506                                 "%s: TDI still set... clearing now.\n",
 507                                adap->name);
 508                         iowrite32(stat, I2C_REG_STS(alg_data));
 509                 }
 510                 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_afi) {
 511                         dev_dbg(&adap->dev,
 512                                 "%s: AFI still set... clearing now.\n",
 513                                adap->name);
 514                         iowrite32(stat, I2C_REG_STS(alg_data));
 515                 }
 516         }
 517
 518         bus_reset_if_active(adap);
 519
 520         /* Cleanup to be sure... */
 521         alg_data->mif.buf = NULL;
 522         alg_data->mif.len = 0;
 523
 524         dev_dbg(&adap->dev, "%s(): exiting, stat = %x\n",
 525                 __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
 526
 527         if (completed != num)
 528                 return ((rc < 0) ? rc : -EREMOTEIO);
 529
 530         return num;
 531 }
 532
 533 static u32 i2c_pnx_func(struct i2c_adapter *adapter)
 534 {
 535         return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 536 }
 537
 538 static struct i2c_algorithm pnx_algorithm = {
 539         .master_xfer = i2c_pnx_xfer,
 540         .functionality = i2c_pnx_func,
 541 };
 542
 543 static int i2c_pnx_controller_suspend(struct platform_device *pdev,
 544                                       pm_message_t state)
 545 {
 546         struct i2c_pnx_data *i2c_pnx = platform_get_drvdata(pdev);
 547         return i2c_pnx->suspend(pdev, state);
 548 }
 549
 550 static int i2c_pnx_controller_resume(struct platform_device *pdev)
 551 {
 552         struct i2c_pnx_data *i2c_pnx = platform_get_drvdata(pdev);
 553         return i2c_pnx->resume(pdev);
 554 }
 555
 556 static int __devinit i2c_pnx_probe(struct platform_device *pdev)
 557 {
 558         unsigned long tmp;
 559         int ret = 0;
 560         struct i2c_pnx_algo_data *alg_data;
 561         int freq_mhz;
 562         struct i2c_pnx_data *i2c_pnx = pdev->dev.platform_data;
 563
 564         if (!i2c_pnx || !i2c_pnx->adapter) {
 565                 dev_err(&pdev->dev, "%s: no platform data supplied\n",
 566                        __FUNCTION__);
 567                 ret = -EINVAL;
 568                 goto out;
 569         }
 570
 571         platform_set_drvdata(pdev, i2c_pnx);
 572
 573         if (i2c_pnx->calculate_input_freq)
 574                 freq_mhz = i2c_pnx->calculate_input_freq(pdev);
 575         else {
 576                 freq_mhz = PNX_DEFAULT_FREQ;
 577                 dev_info(&pdev->dev, "Setting bus frequency to default value: "
 578                        "%d MHz\n", freq_mhz);
 579         }
 580
 581         i2c_pnx->adapter->algo = &pnx_algorithm;
 582
 583         alg_data = i2c_pnx->adapter->algo_data;
 584         init_timer(&alg_data->mif.timer);
 585         alg_data->mif.timer.function = i2c_pnx_timeout;
 586         alg_data->mif.timer.data = (unsigned long)i2c_pnx->adapter;
 587
 588         /* Register I/O resource */
 589         if (!request_region(alg_data->base, I2C_PNX_REGION_SIZE, pdev->name)) {
 590                 dev_err(&pdev->dev,
 591                        "I/O region 0x%08x for I2C already in use.\n",
 592                        alg_data->base);
 593                 ret = -ENODEV;
 594                 goto out_drvdata;
 595         }
 596
 597         if (!(alg_data->ioaddr =
 598                         (u32)ioremap(alg_data->base, I2C_PNX_REGION_SIZE))) {
 599                 dev_err(&pdev->dev, "Couldn't ioremap I2C I/O region\n");
 600                 ret = -ENOMEM;
 601                 goto out_release;
 602         }
 603
 604         i2c_pnx->set_clock_run(pdev);
 605
 606         /*
 607          * Clock Divisor High This value is the number of system clocks
 608          * the serial clock (SCL) will be high.
 609          * For example, if the system clock period is 50 ns and the maximum
 610          * desired serial period is 10000 ns (100 kHz), then CLKHI would be
 611          * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value
 612          * programmed into CLKHI will vary from this slightly due to
 613          * variations in the output pad's rise and fall times as well as
 614          * the deglitching filter length.
 615          */
 616
 617         tmp = ((freq_mhz * 1000) / I2C_PNX_SPEED_KHZ) / 2 - 2;
 618         iowrite32(tmp, I2C_REG_CKH(alg_data));
 619         iowrite32(tmp, I2C_REG_CKL(alg_data));
 620
 621         iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data));
 622         if (wait_reset(I2C_PNX_TIMEOUT, alg_data)) {
 623                 ret = -ENODEV;
 624                 goto out_unmap;
 625         }
 626         init_completion(&alg_data->mif.complete);
 627
 628         ret = request_irq(alg_data->irq, i2c_pnx_interrupt,
 629                         0, pdev->name, i2c_pnx->adapter);
 630         if (ret)
 631                 goto out_clock;
 632
 633         /* Register this adapter with the I2C subsystem */
 634         i2c_pnx->adapter->dev.parent = &pdev->dev;
 635         ret = i2c_add_adapter(i2c_pnx->adapter);
 636         if (ret < 0) {
 637                 dev_err(&pdev->dev, "I2C: Failed to add bus\n");
 638                 goto out_irq;
 639         }
 640
 641         dev_dbg(&pdev->dev, "%s: Master at %#8x, irq %d.\n",
 642                i2c_pnx->adapter->name, alg_data->base, alg_data->irq);
 643
 644         return 0;
 645
 646 out_irq:
 647         free_irq(alg_data->irq, alg_data);
 648 out_clock:
 649         i2c_pnx->set_clock_stop(pdev);
 650 out_unmap:
 651         iounmap((void *)alg_data->ioaddr);
 652 out_release:
 653         release_region(alg_data->base, I2C_PNX_REGION_SIZE);
 654 out_drvdata:
 655         platform_set_drvdata(pdev, NULL);
 656 out:
 657         return ret;
 658 }
 659
 660 static int __devexit i2c_pnx_remove(struct platform_device *pdev)
 661 {
 662         struct i2c_pnx_data *i2c_pnx = platform_get_drvdata(pdev);
 663         struct i2c_adapter *adap = i2c_pnx->adapter;
 664         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
 665
 666         free_irq(alg_data->irq, alg_data);
 667         i2c_del_adapter(adap);
 668         i2c_pnx->set_clock_stop(pdev);
 669         iounmap((void *)alg_data->ioaddr);
 670         release_region(alg_data->base, I2C_PNX_REGION_SIZE);
 671         platform_set_drvdata(pdev, NULL);
 672
 673         return 0;
 674 }
 675
 676 static struct platform_driver i2c_pnx_driver = {
 677         .driver = {
 678                 .name = "pnx-i2c",
 679                 .owner = THIS_MODULE,
 680         },
 681         .probe = i2c_pnx_probe,
 682         .remove = __devexit_p(i2c_pnx_remove),
 683         .suspend = i2c_pnx_controller_suspend,
 684         .resume = i2c_pnx_controller_resume,
 685 };
 686
 687 static int __init i2c_adap_pnx_init(void)
 688 {
 689         return platform_driver_register(&i2c_pnx_driver);
 690 }
 691
 692 static void __exit i2c_adap_pnx_exit(void)
 693 {
 694         platform_driver_unregister(&i2c_pnx_driver);
 695 }
 696
 697 MODULE_AUTHOR("Vitaly Wool, Dennis Kovalev <source@mvista.com>");
 698 MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses");
 699 MODULE_LICENSE("GPL");
 700
 701 /* We need to make sure I2C is initialized before USB */
 702 subsys_initcall(i2c_adap_pnx_init);
 703 module_exit(i2c_adap_pnx_exit);