linux/drivers/i2c/busses/i2c-pnx.c
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   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
  34static 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
  44static 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
  54static 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 */
  80static 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 */
 136static 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 */
 165static 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 */
 235static 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
 308static 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
 385static 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
 407static 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 */
 440static int
 441i2c_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
 533static u32 i2c_pnx_func(struct i2c_adapter *adapter)
 534{
 535        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 536}
 537
 538static struct i2c_algorithm pnx_algorithm = {
 539        .master_xfer = i2c_pnx_xfer,
 540        .functionality = i2c_pnx_func,
 541};
 542
 543#ifdef CONFIG_PM
 544static 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        /* FIXME: shouldn't this be clk_disable? */
 550        clk_enable(alg_data->clk);
 551
 552        return 0;
 553}
 554
 555static int i2c_pnx_controller_resume(struct platform_device *pdev)
 556{
 557        struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev);
 558
 559        return clk_enable(alg_data->clk);
 560}
 561#else
 562#define i2c_pnx_controller_suspend      NULL
 563#define i2c_pnx_controller_resume       NULL
 564#endif
 565
 566static int __devinit i2c_pnx_probe(struct platform_device *pdev)
 567{
 568        unsigned long tmp;
 569        int ret = 0;
 570        struct i2c_pnx_algo_data *alg_data;
 571        unsigned long freq;
 572        struct i2c_pnx_data *i2c_pnx = pdev->dev.platform_data;
 573
 574        if (!i2c_pnx || !i2c_pnx->name) {
 575                dev_err(&pdev->dev, "%s: no platform data supplied\n",
 576                       __func__);
 577                ret = -EINVAL;
 578                goto out;
 579        }
 580
 581        alg_data = kzalloc(sizeof(*alg_data), GFP_KERNEL);
 582        if (!alg_data) {
 583                ret = -ENOMEM;
 584                goto err_kzalloc;
 585        }
 586
 587        platform_set_drvdata(pdev, alg_data);
 588
 589        strlcpy(alg_data->adapter.name, i2c_pnx->name,
 590                sizeof(alg_data->adapter.name));
 591        alg_data->adapter.dev.parent = &pdev->dev;
 592        alg_data->adapter.algo = &pnx_algorithm;
 593        alg_data->adapter.algo_data = alg_data;
 594        alg_data->adapter.nr = pdev->id;
 595        alg_data->i2c_pnx = i2c_pnx;
 596
 597        alg_data->clk = clk_get(&pdev->dev, NULL);
 598        if (IS_ERR(alg_data->clk)) {
 599                ret = PTR_ERR(alg_data->clk);
 600                goto out_drvdata;
 601        }
 602
 603        init_timer(&alg_data->mif.timer);
 604        alg_data->mif.timer.function = i2c_pnx_timeout;
 605        alg_data->mif.timer.data = (unsigned long)alg_data;
 606
 607        /* Register I/O resource */
 608        if (!request_mem_region(i2c_pnx->base, I2C_PNX_REGION_SIZE,
 609                                pdev->name)) {
 610                dev_err(&pdev->dev,
 611                       "I/O region 0x%08x for I2C already in use.\n",
 612                       i2c_pnx->base);
 613                ret = -ENODEV;
 614                goto out_clkget;
 615        }
 616
 617        alg_data->ioaddr = ioremap(i2c_pnx->base, I2C_PNX_REGION_SIZE);
 618        if (!alg_data->ioaddr) {
 619                dev_err(&pdev->dev, "Couldn't ioremap I2C I/O region\n");
 620                ret = -ENOMEM;
 621                goto out_release;
 622        }
 623
 624        ret = clk_enable(alg_data->clk);
 625        if (ret)
 626                goto out_unmap;
 627
 628        freq = clk_get_rate(alg_data->clk);
 629
 630        /*
 631         * Clock Divisor High This value is the number of system clocks
 632         * the serial clock (SCL) will be high.
 633         * For example, if the system clock period is 50 ns and the maximum
 634         * desired serial period is 10000 ns (100 kHz), then CLKHI would be
 635         * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value
 636         * programmed into CLKHI will vary from this slightly due to
 637         * variations in the output pad's rise and fall times as well as
 638         * the deglitching filter length.
 639         */
 640
 641        tmp = ((freq / 1000) / I2C_PNX_SPEED_KHZ) / 2 - 2;
 642        if (tmp > 0x3FF)
 643                tmp = 0x3FF;
 644        iowrite32(tmp, I2C_REG_CKH(alg_data));
 645        iowrite32(tmp, I2C_REG_CKL(alg_data));
 646
 647        iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data));
 648        if (wait_reset(I2C_PNX_TIMEOUT, alg_data)) {
 649                ret = -ENODEV;
 650                goto out_clock;
 651        }
 652        init_completion(&alg_data->mif.complete);
 653
 654        ret = request_irq(i2c_pnx->irq, i2c_pnx_interrupt,
 655                        0, pdev->name, alg_data);
 656        if (ret)
 657                goto out_clock;
 658
 659        /* Register this adapter with the I2C subsystem */
 660        ret = i2c_add_numbered_adapter(&alg_data->adapter);
 661        if (ret < 0) {
 662                dev_err(&pdev->dev, "I2C: Failed to add bus\n");
 663                goto out_irq;
 664        }
 665
 666        dev_dbg(&pdev->dev, "%s: Master at %#8x, irq %d.\n",
 667               alg_data->adapter.name, i2c_pnx->base, i2c_pnx->irq);
 668
 669        return 0;
 670
 671out_irq:
 672        free_irq(i2c_pnx->irq, alg_data);
 673out_clock:
 674        clk_disable(alg_data->clk);
 675out_unmap:
 676        iounmap(alg_data->ioaddr);
 677out_release:
 678        release_mem_region(i2c_pnx->base, I2C_PNX_REGION_SIZE);
 679out_clkget:
 680        clk_put(alg_data->clk);
 681out_drvdata:
 682        kfree(alg_data);
 683err_kzalloc:
 684        platform_set_drvdata(pdev, NULL);
 685out:
 686        return ret;
 687}
 688
 689static int __devexit i2c_pnx_remove(struct platform_device *pdev)
 690{
 691        struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev);
 692        struct i2c_pnx_data *i2c_pnx = alg_data->i2c_pnx;
 693
 694        free_irq(i2c_pnx->irq, alg_data);
 695        i2c_del_adapter(&alg_data->adapter);
 696        clk_disable(alg_data->clk);
 697        iounmap(alg_data->ioaddr);
 698        release_mem_region(i2c_pnx->base, I2C_PNX_REGION_SIZE);
 699        clk_put(alg_data->clk);
 700        kfree(alg_data);
 701        platform_set_drvdata(pdev, NULL);
 702
 703        return 0;
 704}
 705
 706static struct platform_driver i2c_pnx_driver = {
 707        .driver = {
 708                .name = "pnx-i2c",
 709                .owner = THIS_MODULE,
 710        },
 711        .probe = i2c_pnx_probe,
 712        .remove = __devexit_p(i2c_pnx_remove),
 713        .suspend = i2c_pnx_controller_suspend,
 714        .resume = i2c_pnx_controller_resume,
 715};
 716
 717static int __init i2c_adap_pnx_init(void)
 718{
 719        return platform_driver_register(&i2c_pnx_driver);
 720}
 721
 722static void __exit i2c_adap_pnx_exit(void)
 723{
 724        platform_driver_unregister(&i2c_pnx_driver);
 725}
 726
 727MODULE_AUTHOR("Vitaly Wool, Dennis Kovalev <source@mvista.com>");
 728MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses");
 729MODULE_LICENSE("GPL");
 730MODULE_ALIAS("platform:pnx-i2c");
 731
 732/* We need to make sure I2C is initialized before USB */
 733subsys_initcall(i2c_adap_pnx_init);
 734module_exit(i2c_adap_pnx_exit);
 735