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 <linux/io.h>
  23 #include <linux/err.h>
  24 #include <linux/clk.h>
  25 #include <linux/slab.h>
  26
  27 #include <mach/hardware.h>
  28 #include <mach/i2c.h>
  29
  30 #define I2C_PNX_TIMEOUT         10 /* msec */
  31 #define I2C_PNX_SPEED_KHZ       100
  32 #define I2C_PNX_REGION_SIZE     0x100
  33
  34 static inline int wait_timeout(long timeout, struct i2c_pnx_algo_data *data)
  35 {
  36         while (timeout > 0 &&
  37                         (ioread32(I2C_REG_STS(data)) & mstatus_active)) {
  38                 mdelay(1);
  39                 timeout--;
  40         }
  41         return (timeout <= 0);
  42 }
  43
  44 static inline int wait_reset(long timeout, struct i2c_pnx_algo_data *data)
  45 {
  46         while (timeout > 0 &&
  47                         (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) {
  48                 mdelay(1);
  49                 timeout--;
  50         }
  51         return (timeout <= 0);
  52 }
  53
  54 static inline void i2c_pnx_arm_timer(struct i2c_pnx_algo_data *alg_data)
  55 {
  56         struct timer_list *timer = &alg_data->mif.timer;
  57         unsigned long expires = msecs_to_jiffies(I2C_PNX_TIMEOUT);
  58
  59         if (expires <= 1)
  60                 expires = 2;
  61
  62         del_timer_sync(timer);
  63
  64         dev_dbg(&alg_data->adapter.dev, "Timer armed at %lu plus %lu jiffies.\n",
  65                 jiffies, expires);
  66
  67         timer->expires = jiffies + expires;
  68         timer->data = (unsigned long)alg_data;
  69
  70         add_timer(timer);
  71 }
  72
  73 /**
  74  * i2c_pnx_start - start a device
  75  * @slave_addr:         slave address
  76  * @adap:               pointer to adapter structure
  77  *
  78  * Generate a START signal in the desired mode.
  79  */
  80 static int i2c_pnx_start(unsigned char slave_addr,
  81         struct i2c_pnx_algo_data *alg_data)
  82 {
  83         dev_dbg(&alg_data->adapter.dev, "%s(): addr 0x%x mode %d\n", __func__,
  84                 slave_addr, alg_data->mif.mode);
  85
  86         /* Check for 7 bit slave addresses only */
  87         if (slave_addr & ~0x7f) {
  88                 dev_err(&alg_data->adapter.dev,
  89                         "%s: Invalid slave address %x. Only 7-bit addresses are supported\n",
  90                         alg_data->adapter.name, slave_addr);
  91                 return -EINVAL;
  92         }
  93
  94         /* First, make sure bus is idle */
  95         if (wait_timeout(I2C_PNX_TIMEOUT, alg_data)) {
  96                 /* Somebody else is monopolizing the bus */
  97                 dev_err(&alg_data->adapter.dev,
  98                         "%s: Bus busy. Slave addr = %02x, cntrl = %x, stat = %x\n",
  99                         alg_data->adapter.name, slave_addr,
 100                         ioread32(I2C_REG_CTL(alg_data)),
 101                         ioread32(I2C_REG_STS(alg_data)));
 102                 return -EBUSY;
 103         } else if (ioread32(I2C_REG_STS(alg_data)) & mstatus_afi) {
 104                 /* Sorry, we lost the bus */
 105                 dev_err(&alg_data->adapter.dev,
 106                         "%s: Arbitration failure. Slave addr = %02x\n",
 107                         alg_data->adapter.name, slave_addr);
 108                 return -EIO;
 109         }
 110
 111         /*
 112          * OK, I2C is enabled and we have the bus.
 113          * Clear the current TDI and AFI status flags.
 114          */
 115         iowrite32(ioread32(I2C_REG_STS(alg_data)) | mstatus_tdi | mstatus_afi,
 116                   I2C_REG_STS(alg_data));
 117
 118         dev_dbg(&alg_data->adapter.dev, "%s(): sending %#x\n", __func__,
 119                 (slave_addr << 1) | start_bit | alg_data->mif.mode);
 120
 121         /* Write the slave address, START bit and R/W bit */
 122         iowrite32((slave_addr << 1) | start_bit | alg_data->mif.mode,
 123                   I2C_REG_TX(alg_data));
 124
 125         dev_dbg(&alg_data->adapter.dev, "%s(): exit\n", __func__);
 126
 127         return 0;
 128 }
 129
 130 /**
 131  * i2c_pnx_stop - stop a device
 132  * @adap:               pointer to I2C adapter structure
 133  *
 134  * Generate a STOP signal to terminate the master transaction.
 135  */
 136 static void i2c_pnx_stop(struct i2c_pnx_algo_data *alg_data)
 137 {
 138         /* Only 1 msec max timeout due to interrupt context */
 139         long timeout = 1000;
 140
 141         dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n",
 142                 __func__, ioread32(I2C_REG_STS(alg_data)));
 143
 144         /* Write a STOP bit to TX FIFO */
 145         iowrite32(0xff | stop_bit, I2C_REG_TX(alg_data));
 146
 147         /* Wait until the STOP is seen. */
 148         while (timeout > 0 &&
 149                (ioread32(I2C_REG_STS(alg_data)) & mstatus_active)) {
 150                 /* may be called from interrupt context */
 151                 udelay(1);
 152                 timeout--;
 153         }
 154
 155         dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n",
 156                 __func__, ioread32(I2C_REG_STS(alg_data)));
 157 }
 158
 159 /**
 160  * i2c_pnx_master_xmit - transmit data to slave
 161  * @adap:               pointer to I2C adapter structure
 162  *
 163  * Sends one byte of data to the slave
 164  */
 165 static int i2c_pnx_master_xmit(struct i2c_pnx_algo_data *alg_data)
 166 {
 167         u32 val;
 168
 169         dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n",
 170                 __func__, ioread32(I2C_REG_STS(alg_data)));
 171
 172         if (alg_data->mif.len > 0) {
 173                 /* We still have something to talk about... */
 174                 val = *alg_data->mif.buf++;
 175
 176                 if (alg_data->mif.len == 1)
 177                         val |= stop_bit;
 178
 179                 alg_data->mif.len--;
 180                 iowrite32(val, I2C_REG_TX(alg_data));
 181
 182                 dev_dbg(&alg_data->adapter.dev, "%s(): xmit %#x [%d]\n",
 183                         __func__, 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(&alg_data->adapter.dev,
 190                                                 "The bus is still 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(&alg_data->adapter.dev,
 200                                 "%s(): Waking up xfer routine.\n",
 201                                 __func__);
 202
 203                         complete(&alg_data->mif.complete);
 204                 }
 205         } else if (alg_data->mif.len == 0) {
 206                 /* zero-sized transfer */
 207                 i2c_pnx_stop(alg_data);
 208
 209                 /* Disable master interrupts. */
 210                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) &
 211                         ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie),
 212                           I2C_REG_CTL(alg_data));
 213
 214                 /* Stop timer. */
 215                 del_timer_sync(&alg_data->mif.timer);
 216                 dev_dbg(&alg_data->adapter.dev,
 217                         "%s(): Waking up xfer routine after zero-xfer.\n",
 218                         __func__);
 219
 220                 complete(&alg_data->mif.complete);
 221         }
 222
 223         dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n",
 224                 __func__, ioread32(I2C_REG_STS(alg_data)));
 225
 226         return 0;
 227 }
 228
 229 /**
 230  * i2c_pnx_master_rcv - receive data from slave
 231  * @adap:               pointer to I2C adapter structure
 232  *
 233  * Reads one byte data from the slave
 234  */
 235 static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data)
 236 {
 237         unsigned int val = 0;
 238         u32 ctl = 0;
 239
 240         dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n",
 241                 __func__, ioread32(I2C_REG_STS(alg_data)));
 242
 243         /* Check, whether there is already data,
 244          * or we didn't 'ask' for it yet.
 245          */
 246         if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) {
 247                 dev_dbg(&alg_data->adapter.dev,
 248                         "%s(): Write dummy data to fill Rx-fifo...\n",
 249                         __func__);
 250
 251                 if (alg_data->mif.len == 1) {
 252                         /* Last byte, do not acknowledge next rcv. */
 253                         val |= stop_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(&alg_data->adapter.dev, "%s(): rcv 0x%x [%d]\n",
 280                         __func__, val, 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(&alg_data->adapter.dev,
 288                                                 "The bus is still 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(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n",
 303                 __func__, 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         struct i2c_pnx_algo_data *alg_data = dev_id;
 311         u32 stat, ctl;
 312
 313         dev_dbg(&alg_data->adapter.dev,
 314                 "%s(): mstat = %x mctrl = %x, mode = %d\n",
 315                 __func__,
 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(&alg_data->adapter.dev,
 338                         "%s(): Slave did not acknowledge, generating a STOP.\n",
 339                         __func__);
 340                 i2c_pnx_stop(alg_data);
 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(alg_data);
 367                         } else if (alg_data->mif.mode == I2C_SMBUS_READ) {
 368                                 i2c_pnx_master_rcv(alg_data);
 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(&alg_data->adapter.dev,
 378                 "%s(): exiting, stat = %x ctrl = %x.\n",
 379                  __func__, ioread32(I2C_REG_STS(alg_data)),
 380                  ioread32(I2C_REG_CTL(alg_data)));
 381
 382         return IRQ_HANDLED;
 383 }
 384
 385 static void i2c_pnx_timeout(unsigned long data)
 386 {
 387         struct i2c_pnx_algo_data *alg_data = (struct i2c_pnx_algo_data *)data;
 388         u32 ctl;
 389
 390         dev_err(&alg_data->adapter.dev,
 391                 "Master timed out. stat = %04x, cntrl = %04x. 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_pnx_algo_data *alg_data)
 408 {
 409         u32 stat;
 410
 411         if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_active) {
 412                 dev_err(&alg_data->adapter.dev,
 413                         "%s: Bus is still active after xfer. Reset it...\n",
 414                         alg_data->adapter.name);
 415                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
 416                           I2C_REG_CTL(alg_data));
 417                 wait_reset(I2C_PNX_TIMEOUT, alg_data);
 418         } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) {
 419                 /* If there is data in the fifo's after transfer,
 420                  * flush fifo's by reset.
 421                  */
 422                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
 423                           I2C_REG_CTL(alg_data));
 424                 wait_reset(I2C_PNX_TIMEOUT, alg_data);
 425         } else if (stat & mstatus_nai) {
 426                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
 427                           I2C_REG_CTL(alg_data));
 428                 wait_reset(I2C_PNX_TIMEOUT, alg_data);
 429         }
 430 }
 431
 432 /**
 433  * i2c_pnx_xfer - generic transfer entry point
 434  * @adap:               pointer to I2C adapter structure
 435  * @msgs:               array of messages
 436  * @num:                number of messages
 437  *
 438  * Initiates the transfer
 439  */
 440 static int
 441 i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
 442 {
 443         struct i2c_msg *pmsg;
 444         int rc = 0, completed = 0, i;
 445         struct i2c_pnx_algo_data *alg_data = adap->algo_data;
 446         u32 stat = ioread32(I2C_REG_STS(alg_data));
 447
 448         dev_dbg(&alg_data->adapter.dev,
 449                 "%s(): entering: %d messages, stat = %04x.\n",
 450                 __func__, num, ioread32(I2C_REG_STS(alg_data)));
 451
 452         bus_reset_if_active(alg_data);
 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(&alg_data->adapter.dev,
 463                                 "%s: 10 bits addr not supported!\n",
 464                                 alg_data->adapter.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(&alg_data->adapter.dev, "%s(): mode %d, %d bytes\n",
 477                         __func__, alg_data->mif.mode, alg_data->mif.len);
 478
 479                 i2c_pnx_arm_timer(alg_data);
 480
 481                 /* initialize the completion var */
 482                 init_completion(&alg_data->mif.complete);
 483
 484                 /* Enable master interrupt */
 485                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_afie |
 486                                 mcntrl_naie | mcntrl_drmie,
 487                           I2C_REG_CTL(alg_data));
 488
 489                 /* Put start-code and slave-address on the bus. */
 490                 rc = i2c_pnx_start(addr, alg_data);
 491                 if (rc < 0)
 492                         break;
 493
 494                 /* Wait for completion */
 495                 wait_for_completion(&alg_data->mif.complete);
 496
 497                 if (!(rc = alg_data->mif.ret))
 498                         completed++;
 499                 dev_dbg(&alg_data->adapter.dev,
 500                         "%s(): Complete, return code = %d.\n",
 501                         __func__, 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(&alg_data->adapter.dev,
 506                                 "%s: TDI still set... clearing now.\n",
 507                                 alg_data->adapter.name);
 508                         iowrite32(stat, I2C_REG_STS(alg_data));
 509                 }
 510                 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_afi) {
 511                         dev_dbg(&alg_data->adapter.dev,
 512                                 "%s: AFI still set... clearing now.\n",
 513                                 alg_data->adapter.name);
 514                         iowrite32(stat, I2C_REG_STS(alg_data));
 515                 }
 516         }
 517
 518         bus_reset_if_active(alg_data);
 519
 520         /* Cleanup to be sure... */
 521         alg_data->mif.buf = NULL;
 522         alg_data->mif.len = 0;
 523
 524         dev_dbg(&alg_data->adapter.dev, "%s(): exiting, stat = %x\n",
 525                 __func__, 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 #ifdef CONFIG_PM
 544 static int i2c_pnx_controller_suspend(struct platform_device *pdev,
 545                                       pm_message_t state)
 546 {
 547         struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev);
 548
 549         clk_disable(alg_data->clk);
 550
 551         return 0;
 552 }
 553
 554 static int i2c_pnx_controller_resume(struct platform_device *pdev)
 555 {
 556         struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev);
 557
 558         return clk_enable(alg_data->clk);
 559 }
 560 #else
 561 #define i2c_pnx_controller_suspend      NULL
 562 #define i2c_pnx_controller_resume       NULL
 563 #endif
 564
 565 static int __devinit i2c_pnx_probe(struct platform_device *pdev)
 566 {
 567         unsigned long tmp;
 568         int ret = 0;
 569         struct i2c_pnx_algo_data *alg_data;
 570         unsigned long freq;
 571         struct i2c_pnx_data *i2c_pnx = pdev->dev.platform_data;
 572
 573         if (!i2c_pnx || !i2c_pnx->name) {
 574                 dev_err(&pdev->dev, "%s: no platform data supplied\n",
 575                        __func__);
 576                 ret = -EINVAL;
 577                 goto out;
 578         }
 579
 580         alg_data = kzalloc(sizeof(*alg_data), GFP_KERNEL);
 581         if (!alg_data) {
 582                 ret = -ENOMEM;
 583                 goto err_kzalloc;
 584         }
 585
 586         platform_set_drvdata(pdev, alg_data);
 587
 588         strlcpy(alg_data->adapter.name, i2c_pnx->name,
 589                 sizeof(alg_data->adapter.name));
 590         alg_data->adapter.dev.parent = &pdev->dev;
 591         alg_data->adapter.algo = &pnx_algorithm;
 592         alg_data->adapter.algo_data = alg_data;
 593         alg_data->adapter.nr = pdev->id;
 594         alg_data->i2c_pnx = i2c_pnx;
 595
 596         alg_data->clk = clk_get(&pdev->dev, NULL);
 597         if (IS_ERR(alg_data->clk)) {
 598                 ret = PTR_ERR(alg_data->clk);
 599                 goto out_drvdata;
 600         }
 601
 602         init_timer(&alg_data->mif.timer);
 603         alg_data->mif.timer.function = i2c_pnx_timeout;
 604         alg_data->mif.timer.data = (unsigned long)alg_data;
 605
 606         /* Register I/O resource */
 607         if (!request_mem_region(i2c_pnx->base, I2C_PNX_REGION_SIZE,
 608                                 pdev->name)) {
 609                 dev_err(&pdev->dev,
 610                        "I/O region 0x%08x for I2C already in use.\n",
 611                        i2c_pnx->base);
 612                 ret = -ENODEV;
 613                 goto out_clkget;
 614         }
 615
 616         alg_data->ioaddr = ioremap(i2c_pnx->base, I2C_PNX_REGION_SIZE);
 617         if (!alg_data->ioaddr) {
 618                 dev_err(&pdev->dev, "Couldn't ioremap I2C I/O region\n");
 619                 ret = -ENOMEM;
 620                 goto out_release;
 621         }
 622
 623         ret = clk_enable(alg_data->clk);
 624         if (ret)
 625                 goto out_unmap;
 626
 627         freq = clk_get_rate(alg_data->clk);
 628
 629         /*
 630          * Clock Divisor High This value is the number of system clocks
 631          * the serial clock (SCL) will be high.
 632          * For example, if the system clock period is 50 ns and the maximum
 633          * desired serial period is 10000 ns (100 kHz), then CLKHI would be
 634          * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value
 635          * programmed into CLKHI will vary from this slightly due to
 636          * variations in the output pad's rise and fall times as well as
 637          * the deglitching filter length.
 638          */
 639
 640         tmp = ((freq / 1000) / I2C_PNX_SPEED_KHZ) / 2 - 2;
 641         if (tmp > 0x3FF)
 642                 tmp = 0x3FF;
 643         iowrite32(tmp, I2C_REG_CKH(alg_data));
 644         iowrite32(tmp, I2C_REG_CKL(alg_data));
 645
 646         iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data));
 647         if (wait_reset(I2C_PNX_TIMEOUT, alg_data)) {
 648                 ret = -ENODEV;
 649                 goto out_clock;
 650         }
 651         init_completion(&alg_data->mif.complete);
 652
 653         ret = request_irq(i2c_pnx->irq, i2c_pnx_interrupt,
 654                         0, pdev->name, alg_data);
 655         if (ret)
 656                 goto out_clock;
 657
 658         /* Register this adapter with the I2C subsystem */
 659         ret = i2c_add_numbered_adapter(&alg_data->adapter);
 660         if (ret < 0) {
 661                 dev_err(&pdev->dev, "I2C: Failed to add bus\n");
 662                 goto out_irq;
 663         }
 664
 665         dev_dbg(&pdev->dev, "%s: Master at %#8x, irq %d.\n",
 666                alg_data->adapter.name, i2c_pnx->base, i2c_pnx->irq);
 667
 668         return 0;
 669
 670 out_irq:
 671         free_irq(i2c_pnx->irq, alg_data);
 672 out_clock:
 673         clk_disable(alg_data->clk);
 674 out_unmap:
 675         iounmap(alg_data->ioaddr);
 676 out_release:
 677         release_mem_region(i2c_pnx->base, I2C_PNX_REGION_SIZE);
 678 out_clkget:
 679         clk_put(alg_data->clk);
 680 out_drvdata:
 681         kfree(alg_data);
 682 err_kzalloc:
 683         platform_set_drvdata(pdev, NULL);
 684 out:
 685         return ret;
 686 }
 687
 688 static int __devexit i2c_pnx_remove(struct platform_device *pdev)
 689 {
 690         struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev);
 691         struct i2c_pnx_data *i2c_pnx = alg_data->i2c_pnx;
 692
 693         free_irq(i2c_pnx->irq, alg_data);
 694         i2c_del_adapter(&alg_data->adapter);
 695         clk_disable(alg_data->clk);
 696         iounmap(alg_data->ioaddr);
 697         release_mem_region(i2c_pnx->base, I2C_PNX_REGION_SIZE);
 698         clk_put(alg_data->clk);
 699         kfree(alg_data);
 700         platform_set_drvdata(pdev, NULL);
 701
 702         return 0;
 703 }
 704
 705 static struct platform_driver i2c_pnx_driver = {
 706         .driver = {
 707                 .name = "pnx-i2c",
 708                 .owner = THIS_MODULE,
 709         },
 710         .probe = i2c_pnx_probe,
 711         .remove = __devexit_p(i2c_pnx_remove),
 712         .suspend = i2c_pnx_controller_suspend,
 713         .resume = i2c_pnx_controller_resume,
 714 };
 715
 716 static int __init i2c_adap_pnx_init(void)
 717 {
 718         return platform_driver_register(&i2c_pnx_driver);
 719 }
 720
 721 static void __exit i2c_adap_pnx_exit(void)
 722 {
 723         platform_driver_unregister(&i2c_pnx_driver);
 724 }
 725
 726 MODULE_AUTHOR("Vitaly Wool, Dennis Kovalev <source@mvista.com>");
 727 MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses");
 728 MODULE_LICENSE("GPL");
 729 MODULE_ALIAS("platform:pnx-i2c");
 730
 731 /* We need to make sure I2C is initialized before USB */
 732 subsys_initcall(i2c_adap_pnx_init);
 733 module_exit(i2c_adap_pnx_exit);