drivers/i2c/busses/i2c-bfin-twi.c

   1 /*
   2  * drivers/i2c/busses/i2c-bfin-twi.c
   3  *
   4  * Description: Driver for Blackfin Two Wire Interface
   5  *
   6  * Author:      sonicz  <sonic.zhang@analog.com>
   7  *
   8  * Copyright (c) 2005-2007 Analog Devices, Inc.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23  */
  24
  25 #include <linux/module.h>
  26 #include <linux/kernel.h>
  27 #include <linux/init.h>
  28 #include <linux/i2c.h>
  29 #include <linux/mm.h>
  30 #include <linux/timer.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/completion.h>
  33 #include <linux/interrupt.h>
  34 #include <linux/platform_device.h>
  35
  36 #include <asm/blackfin.h>
  37 #include <asm/irq.h>
  38
  39 #define POLL_TIMEOUT       (2 * HZ)
  40
  41 /* SMBus mode*/
  42 #define TWI_I2C_MODE_STANDARD           0x01
  43 #define TWI_I2C_MODE_STANDARDSUB        0x02
  44 #define TWI_I2C_MODE_COMBINED           0x04
  45
  46 struct bfin_twi_iface {
  47         int                     irq;
  48         spinlock_t              lock;
  49         char                    read_write;
  50         u8                      command;
  51         u8                      *transPtr;
  52         int                     readNum;
  53         int                     writeNum;
  54         int                     cur_mode;
  55         int                     manual_stop;
  56         int                     result;
  57         int                     timeout_count;
  58         struct timer_list       timeout_timer;
  59         struct i2c_adapter      adap;
  60         struct completion       complete;
  61 };
  62
  63 static struct bfin_twi_iface twi_iface;
  64
  65 static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
  66 {
  67         unsigned short twi_int_status = bfin_read_TWI_INT_STAT();
  68         unsigned short mast_stat = bfin_read_TWI_MASTER_STAT();
  69
  70         if (twi_int_status & XMTSERV) {
  71                 /* Transmit next data */
  72                 if (iface->writeNum > 0) {
  73                         bfin_write_TWI_XMT_DATA8(*(iface->transPtr++));
  74                         iface->writeNum--;
  75                 }
  76                 /* start receive immediately after complete sending in
  77                  * combine mode.
  78                  */
  79                 else if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
  80                         bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL()
  81                                 | MDIR | RSTART);
  82                 } else if (iface->manual_stop)
  83                         bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL()
  84                                 | STOP);
  85                 SSYNC();
  86                 /* Clear status */
  87                 bfin_write_TWI_INT_STAT(XMTSERV);
  88                 SSYNC();
  89         }
  90         if (twi_int_status & RCVSERV) {
  91                 if (iface->readNum > 0) {
  92                         /* Receive next data */
  93                         *(iface->transPtr) = bfin_read_TWI_RCV_DATA8();
  94                         if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
  95                                 /* Change combine mode into sub mode after
  96                                  * read first data.
  97                                  */
  98                                 iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
  99                                 /* Get read number from first byte in block
 100                                  * combine mode.
 101                                  */
 102                                 if (iface->readNum == 1 && iface->manual_stop)
 103                                         iface->readNum = *iface->transPtr + 1;
 104                         }
 105                         iface->transPtr++;
 106                         iface->readNum--;
 107                 } else if (iface->manual_stop) {
 108                         bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL()
 109                                 | STOP);
 110                         SSYNC();
 111                 }
 112                 /* Clear interrupt source */
 113                 bfin_write_TWI_INT_STAT(RCVSERV);
 114                 SSYNC();
 115         }
 116         if (twi_int_status & MERR) {
 117                 bfin_write_TWI_INT_STAT(MERR);
 118                 bfin_write_TWI_INT_MASK(0);
 119                 bfin_write_TWI_MASTER_STAT(0x3e);
 120                 bfin_write_TWI_MASTER_CTL(0);
 121                 SSYNC();
 122                 iface->result = -1;
 123                 /* if both err and complete int stats are set, return proper
 124                  * results.
 125                  */
 126                 if (twi_int_status & MCOMP) {
 127                         bfin_write_TWI_INT_STAT(MCOMP);
 128                         bfin_write_TWI_INT_MASK(0);
 129                         bfin_write_TWI_MASTER_CTL(0);
 130                         SSYNC();
 131                         /* If it is a quick transfer, only address bug no data,
 132                          * not an err, return 1.
 133                          */
 134                         if (iface->writeNum == 0 && (mast_stat & BUFRDERR))
 135                                 iface->result = 1;
 136                         /* If address not acknowledged return -1,
 137                          * else return 0.
 138                          */
 139                         else if (!(mast_stat & ANAK))
 140                                 iface->result = 0;
 141                 }
 142                 complete(&iface->complete);
 143                 return;
 144         }
 145         if (twi_int_status & MCOMP) {
 146                 bfin_write_TWI_INT_STAT(MCOMP);
 147                 SSYNC();
 148                 if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
 149                         if (iface->readNum == 0) {
 150                                 /* set the read number to 1 and ask for manual
 151                                  * stop in block combine mode
 152                                  */
 153                                 iface->readNum = 1;
 154                                 iface->manual_stop = 1;
 155                                 bfin_write_TWI_MASTER_CTL(
 156                                         bfin_read_TWI_MASTER_CTL()
 157                                         | (0xff << 6));
 158                         } else {
 159                                 /* set the readd number in other
 160                                  * combine mode.
 161                                  */
 162                                 bfin_write_TWI_MASTER_CTL(
 163                                         (bfin_read_TWI_MASTER_CTL() &
 164                                         (~(0xff << 6))) |
 165                                         ( iface->readNum << 6));
 166                         }
 167                         /* remove restart bit and enable master receive */
 168                         bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() &
 169                                 ~RSTART);
 170                         bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() |
 171                                 MEN | MDIR);
 172                         SSYNC();
 173                 } else {
 174                         iface->result = 1;
 175                         bfin_write_TWI_INT_MASK(0);
 176                         bfin_write_TWI_MASTER_CTL(0);
 177                         SSYNC();
 178                         complete(&iface->complete);
 179                 }
 180         }
 181 }
 182
 183 /* Interrupt handler */
 184 static irqreturn_t bfin_twi_interrupt_entry(int irq, void *dev_id)
 185 {
 186         struct bfin_twi_iface *iface = dev_id;
 187         unsigned long flags;
 188
 189         spin_lock_irqsave(&iface->lock, flags);
 190         del_timer(&iface->timeout_timer);
 191         bfin_twi_handle_interrupt(iface);
 192         spin_unlock_irqrestore(&iface->lock, flags);
 193         return IRQ_HANDLED;
 194 }
 195
 196 static void bfin_twi_timeout(unsigned long data)
 197 {
 198         struct bfin_twi_iface *iface = (struct bfin_twi_iface *)data;
 199         unsigned long flags;
 200
 201         spin_lock_irqsave(&iface->lock, flags);
 202         bfin_twi_handle_interrupt(iface);
 203         if (iface->result == 0) {
 204                 iface->timeout_count--;
 205                 if (iface->timeout_count > 0) {
 206                         iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 207                         add_timer(&iface->timeout_timer);
 208                 } else {
 209                         iface->result = -1;
 210                         complete(&iface->complete);
 211                 }
 212         }
 213         spin_unlock_irqrestore(&iface->lock, flags);
 214 }
 215
 216 /*
 217  * Generic i2c master transfer entrypoint
 218  */
 219 static int bfin_twi_master_xfer(struct i2c_adapter *adap,
 220                                 struct i2c_msg *msgs, int num)
 221 {
 222         struct bfin_twi_iface *iface = adap->algo_data;
 223         struct i2c_msg *pmsg;
 224         int i, ret;
 225         int rc = 0;
 226
 227         if (!(bfin_read_TWI_CONTROL() & TWI_ENA))
 228                 return -ENXIO;
 229
 230         while (bfin_read_TWI_MASTER_STAT() & BUSBUSY) {
 231                 yield();
 232         }
 233
 234         ret = 0;
 235         for (i = 0; rc >= 0 && i < num; i++) {
 236                 pmsg = &msgs[i];
 237                 if (pmsg->flags & I2C_M_TEN) {
 238                         dev_err(&(adap->dev), "i2c-bfin-twi: 10 bits addr "
 239                                 "not supported !\n");
 240                         rc = -EINVAL;
 241                         break;
 242                 }
 243
 244                 iface->cur_mode = TWI_I2C_MODE_STANDARD;
 245                 iface->manual_stop = 0;
 246                 iface->transPtr = pmsg->buf;
 247                 iface->writeNum = iface->readNum = pmsg->len;
 248                 iface->result = 0;
 249                 iface->timeout_count = 10;
 250                 /* Set Transmit device address */
 251                 bfin_write_TWI_MASTER_ADDR(pmsg->addr);
 252
 253                 /* FIFO Initiation. Data in FIFO should be
 254                  *  discarded before start a new operation.
 255                  */
 256                 bfin_write_TWI_FIFO_CTL(0x3);
 257                 SSYNC();
 258                 bfin_write_TWI_FIFO_CTL(0);
 259                 SSYNC();
 260
 261                 if (pmsg->flags & I2C_M_RD)
 262                         iface->read_write = I2C_SMBUS_READ;
 263                 else {
 264                         iface->read_write = I2C_SMBUS_WRITE;
 265                         /* Transmit first data */
 266                         if (iface->writeNum > 0) {
 267                                 bfin_write_TWI_XMT_DATA8(*(iface->transPtr++));
 268                                 iface->writeNum--;
 269                                 SSYNC();
 270                         }
 271                 }
 272
 273                 /* clear int stat */
 274                 bfin_write_TWI_INT_STAT(MERR|MCOMP|XMTSERV|RCVSERV);
 275
 276                 /* Interrupt mask . Enable XMT, RCV interrupt */
 277                 bfin_write_TWI_INT_MASK(MCOMP | MERR |
 278                         ((iface->read_write == I2C_SMBUS_READ)?
 279                         RCVSERV : XMTSERV));
 280                 SSYNC();
 281
 282                 if (pmsg->len > 0 && pmsg->len <= 255)
 283                         bfin_write_TWI_MASTER_CTL(pmsg->len << 6);
 284                 else if (pmsg->len > 255) {
 285                         bfin_write_TWI_MASTER_CTL(0xff << 6);
 286                         iface->manual_stop = 1;
 287                 } else
 288                         break;
 289
 290                 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 291                 add_timer(&iface->timeout_timer);
 292
 293                 /* Master enable */
 294                 bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | MEN |
 295                         ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
 296                         ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
 297                 SSYNC();
 298
 299                 wait_for_completion(&iface->complete);
 300
 301                 rc = iface->result;
 302                 if (rc == 1)
 303                         ret++;
 304                 else if (rc == -1)
 305                         break;
 306         }
 307
 308         return ret;
 309 }
 310
 311 /*
 312  * SMBus type transfer entrypoint
 313  */
 314
 315 int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
 316                         unsigned short flags, char read_write,
 317                         u8 command, int size, union i2c_smbus_data *data)
 318 {
 319         struct bfin_twi_iface *iface = adap->algo_data;
 320         int rc = 0;
 321
 322         if (!(bfin_read_TWI_CONTROL() & TWI_ENA))
 323                 return -ENXIO;
 324
 325         while (bfin_read_TWI_MASTER_STAT() & BUSBUSY) {
 326                 yield();
 327         }
 328
 329         iface->writeNum = 0;
 330         iface->readNum = 0;
 331
 332         /* Prepare datas & select mode */
 333         switch (size) {
 334         case I2C_SMBUS_QUICK:
 335                 iface->transPtr = NULL;
 336                 iface->cur_mode = TWI_I2C_MODE_STANDARD;
 337                 break;
 338         case I2C_SMBUS_BYTE:
 339                 if (data == NULL)
 340                         iface->transPtr = NULL;
 341                 else {
 342                         if (read_write == I2C_SMBUS_READ)
 343                                 iface->readNum = 1;
 344                         else
 345                                 iface->writeNum = 1;
 346                         iface->transPtr = &data->byte;
 347                 }
 348                 iface->cur_mode = TWI_I2C_MODE_STANDARD;
 349                 break;
 350         case I2C_SMBUS_BYTE_DATA:
 351                 if (read_write == I2C_SMBUS_READ) {
 352                         iface->readNum = 1;
 353                         iface->cur_mode = TWI_I2C_MODE_COMBINED;
 354                 } else {
 355                         iface->writeNum = 1;
 356                         iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
 357                 }
 358                 iface->transPtr = &data->byte;
 359                 break;
 360         case I2C_SMBUS_WORD_DATA:
 361                 if (read_write == I2C_SMBUS_READ) {
 362                         iface->readNum = 2;
 363                         iface->cur_mode = TWI_I2C_MODE_COMBINED;
 364                 } else {
 365                         iface->writeNum = 2;
 366                         iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
 367                 }
 368                 iface->transPtr = (u8 *)&data->word;
 369                 break;
 370         case I2C_SMBUS_PROC_CALL:
 371                 iface->writeNum = 2;
 372                 iface->readNum = 2;
 373                 iface->cur_mode = TWI_I2C_MODE_COMBINED;
 374                 iface->transPtr = (u8 *)&data->word;
 375                 break;
 376         case I2C_SMBUS_BLOCK_DATA:
 377                 if (read_write == I2C_SMBUS_READ) {
 378                         iface->readNum = 0;
 379                         iface->cur_mode = TWI_I2C_MODE_COMBINED;
 380                 } else {
 381                         iface->writeNum = data->block[0] + 1;
 382                         iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
 383                 }
 384                 iface->transPtr = data->block;
 385                 break;
 386         default:
 387                 return -1;
 388         }
 389
 390         iface->result = 0;
 391         iface->manual_stop = 0;
 392         iface->read_write = read_write;
 393         iface->command = command;
 394         iface->timeout_count = 10;
 395
 396         /* FIFO Initiation. Data in FIFO should be discarded before
 397          * start a new operation.
 398          */
 399         bfin_write_TWI_FIFO_CTL(0x3);
 400         SSYNC();
 401         bfin_write_TWI_FIFO_CTL(0);
 402
 403         /* clear int stat */
 404         bfin_write_TWI_INT_STAT(MERR|MCOMP|XMTSERV|RCVSERV);
 405
 406         /* Set Transmit device address */
 407         bfin_write_TWI_MASTER_ADDR(addr);
 408         SSYNC();
 409
 410         iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 411         add_timer(&iface->timeout_timer);
 412
 413         switch (iface->cur_mode) {
 414         case TWI_I2C_MODE_STANDARDSUB:
 415                 bfin_write_TWI_XMT_DATA8(iface->command);
 416                 bfin_write_TWI_INT_MASK(MCOMP | MERR |
 417                         ((iface->read_write == I2C_SMBUS_READ) ?
 418                         RCVSERV : XMTSERV));
 419                 SSYNC();
 420
 421                 if (iface->writeNum + 1 <= 255)
 422                         bfin_write_TWI_MASTER_CTL((iface->writeNum + 1) << 6);
 423                 else {
 424                         bfin_write_TWI_MASTER_CTL(0xff << 6);
 425                         iface->manual_stop = 1;
 426                 }
 427                 /* Master enable */
 428                 bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | MEN |
 429                         ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
 430                 break;
 431         case TWI_I2C_MODE_COMBINED:
 432                 bfin_write_TWI_XMT_DATA8(iface->command);
 433                 bfin_write_TWI_INT_MASK(MCOMP | MERR | RCVSERV | XMTSERV);
 434                 SSYNC();
 435
 436                 if (iface->writeNum > 0)
 437                         bfin_write_TWI_MASTER_CTL((iface->writeNum + 1) << 6);
 438                 else
 439                         bfin_write_TWI_MASTER_CTL(0x1 << 6);
 440                 /* Master enable */
 441                 bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | MEN |
 442                         ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
 443                 break;
 444         default:
 445                 bfin_write_TWI_MASTER_CTL(0);
 446                 if (size != I2C_SMBUS_QUICK) {
 447                         /* Don't access xmit data register when this is a
 448                          * read operation.
 449                          */
 450                         if (iface->read_write != I2C_SMBUS_READ) {
 451                                 if (iface->writeNum > 0) {
 452                                         bfin_write_TWI_XMT_DATA8(*(iface->transPtr++));
 453                                         if (iface->writeNum <= 255)
 454                                                 bfin_write_TWI_MASTER_CTL(iface->writeNum << 6);
 455                                         else {
 456                                                 bfin_write_TWI_MASTER_CTL(0xff << 6);
 457                                                 iface->manual_stop = 1;
 458                                         }
 459                                         iface->writeNum--;
 460                                 } else {
 461                                         bfin_write_TWI_XMT_DATA8(iface->command);
 462                                         bfin_write_TWI_MASTER_CTL(1 << 6);
 463                                 }
 464                         } else {
 465                                 if (iface->readNum > 0 && iface->readNum <= 255)
 466                                         bfin_write_TWI_MASTER_CTL(iface->readNum << 6);
 467                                 else if (iface->readNum > 255) {
 468                                         bfin_write_TWI_MASTER_CTL(0xff << 6);
 469                                         iface->manual_stop = 1;
 470                                 } else {
 471                                         del_timer(&iface->timeout_timer);
 472                                         break;
 473                                 }
 474                         }
 475                 }
 476                 bfin_write_TWI_INT_MASK(MCOMP | MERR |
 477                         ((iface->read_write == I2C_SMBUS_READ) ?
 478                         RCVSERV : XMTSERV));
 479                 SSYNC();
 480
 481                 /* Master enable */
 482                 bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | MEN |
 483                         ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
 484                         ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
 485                 break;
 486         }
 487         SSYNC();
 488
 489         wait_for_completion(&iface->complete);
 490
 491         rc = (iface->result >= 0) ? 0 : -1;
 492
 493         return rc;
 494 }
 495
 496 /*
 497  * Return what the adapter supports
 498  */
 499 static u32 bfin_twi_functionality(struct i2c_adapter *adap)
 500 {
 501         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 502                I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 503                I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_PROC_CALL |
 504                I2C_FUNC_I2C;
 505 }
 506
 507
 508 static struct i2c_algorithm bfin_twi_algorithm = {
 509         .master_xfer   = bfin_twi_master_xfer,
 510         .smbus_xfer    = bfin_twi_smbus_xfer,
 511         .functionality = bfin_twi_functionality,
 512 };
 513
 514
 515 static int i2c_bfin_twi_suspend(struct platform_device *dev, pm_message_t state)
 516 {
 517 /*      struct bfin_twi_iface *iface = platform_get_drvdata(dev);*/
 518
 519         /* Disable TWI */
 520         bfin_write_TWI_CONTROL(bfin_read_TWI_CONTROL() & ~TWI_ENA);
 521         SSYNC();
 522
 523         return 0;
 524 }
 525
 526 static int i2c_bfin_twi_resume(struct platform_device *dev)
 527 {
 528 /*      struct bfin_twi_iface *iface = platform_get_drvdata(dev);*/
 529
 530         /* Enable TWI */
 531         bfin_write_TWI_CONTROL(bfin_read_TWI_CONTROL() | TWI_ENA);
 532         SSYNC();
 533
 534         return 0;
 535 }
 536
 537 static int i2c_bfin_twi_probe(struct platform_device *dev)
 538 {
 539         struct bfin_twi_iface *iface = &twi_iface;
 540         struct i2c_adapter *p_adap;
 541         int rc;
 542
 543         spin_lock_init(&(iface->lock));
 544         init_completion(&(iface->complete));
 545         iface->irq = IRQ_TWI;
 546
 547         init_timer(&(iface->timeout_timer));
 548         iface->timeout_timer.function = bfin_twi_timeout;
 549         iface->timeout_timer.data = (unsigned long)iface;
 550
 551         p_adap = &iface->adap;
 552         p_adap->id = I2C_HW_BLACKFIN;
 553         p_adap->nr = dev->id;
 554         strlcpy(p_adap->name, dev->name, sizeof(p_adap->name));
 555         p_adap->algo = &bfin_twi_algorithm;
 556         p_adap->algo_data = iface;
 557         p_adap->class = I2C_CLASS_ALL;
 558         p_adap->dev.parent = &dev->dev;
 559
 560         rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
 561                 IRQF_DISABLED, dev->name, iface);
 562         if (rc) {
 563                 dev_err(&(p_adap->dev), "i2c-bfin-twi: can't get IRQ %d !\n",
 564                         iface->irq);
 565                 return -ENODEV;
 566         }
 567
 568         /* Set TWI internal clock as 10MHz */
 569         bfin_write_TWI_CONTROL(((get_sclk() / 1024 / 1024 + 5) / 10) & 0x7F);
 570
 571         /* Set Twi interface clock as specified */
 572         bfin_write_TWI_CLKDIV((( 5*1024 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ )
 573                         << 8) | (( 5*1024 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ )
 574                         & 0xFF));
 575
 576         /* Enable TWI */
 577         bfin_write_TWI_CONTROL(bfin_read_TWI_CONTROL() | TWI_ENA);
 578         SSYNC();
 579
 580         rc = i2c_add_numbered_adapter(p_adap);
 581         if (rc < 0)
 582                 free_irq(iface->irq, iface);
 583         else
 584                 platform_set_drvdata(dev, iface);
 585
 586         return rc;
 587 }
 588
 589 static int i2c_bfin_twi_remove(struct platform_device *pdev)
 590 {
 591         struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
 592
 593         platform_set_drvdata(pdev, NULL);
 594
 595         i2c_del_adapter(&(iface->adap));
 596         free_irq(iface->irq, iface);
 597
 598         return 0;
 599 }
 600
 601 static struct platform_driver i2c_bfin_twi_driver = {
 602         .probe          = i2c_bfin_twi_probe,
 603         .remove         = i2c_bfin_twi_remove,
 604         .suspend        = i2c_bfin_twi_suspend,
 605         .resume         = i2c_bfin_twi_resume,
 606         .driver         = {
 607                 .name   = "i2c-bfin-twi",
 608                 .owner  = THIS_MODULE,
 609         },
 610 };
 611
 612 static int __init i2c_bfin_twi_init(void)
 613 {
 614         pr_info("I2C: Blackfin I2C TWI driver\n");
 615
 616         return platform_driver_register(&i2c_bfin_twi_driver);
 617 }
 618
 619 static void __exit i2c_bfin_twi_exit(void)
 620 {
 621         platform_driver_unregister(&i2c_bfin_twi_driver);
 622 }
 623
 624 MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>");
 625 MODULE_DESCRIPTION("I2C-Bus adapter routines for Blackfin TWI");
 626 MODULE_LICENSE("GPL");
 627
 628 module_init(i2c_bfin_twi_init);
 629 module_exit(i2c_bfin_twi_exit);