drivers/i2c/busses/i2c-keywest.c

   1 /*
   2     i2c Support for Apple Keywest I2C Bus Controller
   3
   4     Copyright (c) 2001 Benjamin Herrenschmidt <benh@kernel.crashing.org>
   5
   6     Original work by
   7
   8     Copyright (c) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
   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., 675 Mass Ave, Cambridge, MA 02139, USA.
  23
  24     Changes:
  25
  26     2001/12/13 BenH     New implementation
  27     2001/12/15 BenH     Add support for "byte" and "quick"
  28                         transfers. Add i2c_xfer routine.
  29     2003/09/21 BenH     Rework state machine with Paulus help
  30     2004/01/21 BenH     Merge in Greg KH changes, polled mode is back
  31     2004/02/05 BenH     Merge 64 bits fixes from the g5 ppc64 tree
  32
  33     My understanding of the various modes supported by keywest are:
  34
  35      - Dumb mode : not implemented, probably direct tweaking of lines
  36      - Standard mode : simple i2c transaction of type
  37          S Addr R/W A Data A Data ... T
  38      - Standard sub mode : combined 8 bit subaddr write with data read
  39          S Addr R/W A SubAddr A Data A Data ... T
  40      - Combined mode : Subaddress and Data sequences appended with no stop
  41          S Addr R/W A SubAddr S Addr R/W A Data A Data ... T
  42
  43     Currently, this driver uses only Standard mode for i2c xfer, and
  44     smbus byte & quick transfers ; and uses StandardSub mode for
  45     other smbus transfers instead of combined as we need that for the
  46     sound driver to be happy
  47 */
  48
  49 #include <linux/config.h>
  50 #include <linux/module.h>
  51 #include <linux/config.h>
  52 #include <linux/kernel.h>
  53 #include <linux/ioport.h>
  54 #include <linux/pci.h>
  55 #include <linux/types.h>
  56 #include <linux/delay.h>
  57 #include <linux/i2c.h>
  58 #include <linux/init.h>
  59 #include <linux/mm.h>
  60 #include <linux/timer.h>
  61 #include <linux/spinlock.h>
  62 #include <linux/completion.h>
  63 #include <linux/interrupt.h>
  64
  65 #include <asm/io.h>
  66 #include <asm/prom.h>
  67 #include <asm/machdep.h>
  68 #include <asm/pmac_feature.h>
  69 #include <asm/pmac_low_i2c.h>
  70
  71 #include "i2c-keywest.h"
  72
  73 #undef POLLED_MODE
  74
  75 /* Some debug macros */
  76 #define WRONG_STATE(name) do {\
  77                 pr_debug("KW: wrong state. Got %s, state: %s (isr: %02x)\n", \
  78                          name, __kw_state_names[iface->state], isr);    \
  79         } while(0)
  80
  81 #ifdef DEBUG
  82 static const char *__kw_state_names[] = {
  83         "state_idle",
  84         "state_addr",
  85         "state_read",
  86         "state_write",
  87         "state_stop",
  88         "state_dead"
  89 };
  90 #endif /* DEBUG */
  91
  92 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
  93 MODULE_DESCRIPTION("I2C driver for Apple's Keywest");
  94 MODULE_LICENSE("GPL");
  95 MODULE_PARM(probe, "i");
  96
  97 static int probe = 0;
  98
  99 #ifdef POLLED_MODE
 100 /* Don't schedule, the g5 fan controller is too
 101  * timing sensitive
 102  */
 103 static u8
 104 wait_interrupt(struct keywest_iface* iface)
 105 {
 106         int i;
 107         u8 isr;
 108
 109         for (i = 0; i < 200000; i++) {
 110                 isr = read_reg(reg_isr) & KW_I2C_IRQ_MASK;
 111                 if (isr != 0)
 112                         return isr;
 113                 udelay(10);
 114         }
 115         return isr;
 116 }
 117 #endif /* POLLED_MODE */
 118
 119 static void
 120 do_stop(struct keywest_iface* iface, int result)
 121 {
 122         write_reg(reg_control, KW_I2C_CTL_STOP);
 123         iface->state = state_stop;
 124         iface->result = result;
 125 }
 126
 127 /* Main state machine for standard & standard sub mode */
 128 static void
 129 handle_interrupt(struct keywest_iface *iface, u8 isr)
 130 {
 131         int ack;
 132
 133         if (isr == 0) {
 134                 if (iface->state != state_stop) {
 135                         pr_debug("KW: Timeout !\n");
 136                         do_stop(iface, -EIO);
 137                 }
 138                 if (iface->state == state_stop) {
 139                         ack = read_reg(reg_status);
 140                         if (!(ack & KW_I2C_STAT_BUSY)) {
 141                                 iface->state = state_idle;
 142                                 write_reg(reg_ier, 0x00);
 143 #ifndef POLLED_MODE
 144                                 complete(&iface->complete);
 145 #endif /* POLLED_MODE */
 146                         }
 147                 }
 148                 return;
 149         }
 150
 151         if (isr & KW_I2C_IRQ_ADDR) {
 152                 ack = read_reg(reg_status);
 153                 if (iface->state != state_addr) {
 154                         write_reg(reg_isr, KW_I2C_IRQ_ADDR);
 155                         WRONG_STATE("KW_I2C_IRQ_ADDR");
 156                         do_stop(iface, -EIO);
 157                         return;
 158                 }
 159                 if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
 160                         iface->state = state_stop;
 161                         iface->result = -ENODEV;
 162                         pr_debug("KW: NAK on address\n");
 163                 } else {
 164                         /* Handle rw "quick" mode */
 165                         if (iface->datalen == 0) {
 166                                 do_stop(iface, 0);
 167                         } else if (iface->read_write == I2C_SMBUS_READ) {
 168                                 iface->state = state_read;
 169                                 if (iface->datalen > 1)
 170                                         write_reg(reg_control, KW_I2C_CTL_AAK);
 171                         } else {
 172                                 iface->state = state_write;
 173                                 write_reg(reg_data, *(iface->data++));
 174                                 iface->datalen--;
 175                         }
 176                 }
 177                 write_reg(reg_isr, KW_I2C_IRQ_ADDR);
 178         }
 179
 180         if (isr & KW_I2C_IRQ_DATA) {
 181                 if (iface->state == state_read) {
 182                         *(iface->data++) = read_reg(reg_data);
 183                         write_reg(reg_isr, KW_I2C_IRQ_DATA);
 184                         iface->datalen--;
 185                         if (iface->datalen == 0)
 186                                 iface->state = state_stop;
 187                         else if (iface->datalen == 1)
 188                                 write_reg(reg_control, 0);
 189                 } else if (iface->state == state_write) {
 190                         /* Check ack status */
 191                         ack = read_reg(reg_status);
 192                         if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
 193                                 pr_debug("KW: nack on data write (%x): %x\n",
 194                                     iface->data[-1], ack);
 195                                 do_stop(iface, -EIO);
 196                         } else if (iface->datalen) {
 197                                 write_reg(reg_data, *(iface->data++));
 198                                 iface->datalen--;
 199                         } else {
 200                                 write_reg(reg_control, KW_I2C_CTL_STOP);
 201                                 iface->state = state_stop;
 202                                 iface->result = 0;
 203                         }
 204                         write_reg(reg_isr, KW_I2C_IRQ_DATA);
 205                 } else {
 206                         write_reg(reg_isr, KW_I2C_IRQ_DATA);
 207                         WRONG_STATE("KW_I2C_IRQ_DATA");
 208                         if (iface->state != state_stop)
 209                                 do_stop(iface, -EIO);
 210                 }
 211         }
 212
 213         if (isr & KW_I2C_IRQ_STOP) {
 214                 write_reg(reg_isr, KW_I2C_IRQ_STOP);
 215                 if (iface->state != state_stop) {
 216                         WRONG_STATE("KW_I2C_IRQ_STOP");
 217                         iface->result = -EIO;
 218                 }
 219                 iface->state = state_idle;
 220                 write_reg(reg_ier, 0x00);
 221 #ifndef POLLED_MODE
 222                 complete(&iface->complete);
 223 #endif /* POLLED_MODE */
 224         }
 225
 226         if (isr & KW_I2C_IRQ_START)
 227                 write_reg(reg_isr, KW_I2C_IRQ_START);
 228 }
 229
 230 #ifndef POLLED_MODE
 231
 232 /* Interrupt handler */
 233 static irqreturn_t
 234 keywest_irq(int irq, void *dev_id, struct pt_regs *regs)
 235 {
 236         struct keywest_iface *iface = (struct keywest_iface *)dev_id;
 237         unsigned long flags;
 238
 239         spin_lock_irqsave(&iface->lock, flags);
 240         del_timer(&iface->timeout_timer);
 241         handle_interrupt(iface, read_reg(reg_isr));
 242         if (iface->state != state_idle) {
 243                 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 244                 add_timer(&iface->timeout_timer);
 245         }
 246         spin_unlock_irqrestore(&iface->lock, flags);
 247         return IRQ_HANDLED;
 248 }
 249
 250 static void
 251 keywest_timeout(unsigned long data)
 252 {
 253         struct keywest_iface *iface = (struct keywest_iface *)data;
 254         unsigned long flags;
 255
 256         pr_debug("timeout !\n");
 257         spin_lock_irqsave(&iface->lock, flags);
 258         handle_interrupt(iface, read_reg(reg_isr));
 259         if (iface->state != state_idle) {
 260                 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 261                 add_timer(&iface->timeout_timer);
 262         }
 263         spin_unlock_irqrestore(&iface->lock, flags);
 264 }
 265
 266 #endif /* POLLED_MODE */
 267
 268 /*
 269  * SMBUS-type transfer entrypoint
 270  */
 271 static s32
 272 keywest_smbus_xfer(     struct i2c_adapter*     adap,
 273                         u16                     addr,
 274                         unsigned short          flags,
 275                         char                    read_write,
 276                         u8                      command,
 277                         int                     size,
 278                         union i2c_smbus_data*   data)
 279 {
 280         struct keywest_chan* chan = i2c_get_adapdata(adap);
 281         struct keywest_iface* iface = chan->iface;
 282         int len;
 283         u8* buffer;
 284         u16 cur_word;
 285         int rc = 0;
 286
 287         if (iface->state == state_dead)
 288                 return -ENXIO;
 289
 290         /* Prepare datas & select mode */
 291         iface->cur_mode &= ~KW_I2C_MODE_MODE_MASK;
 292         switch (size) {
 293         case I2C_SMBUS_QUICK:
 294                 len = 0;
 295                 buffer = NULL;
 296                 iface->cur_mode |= KW_I2C_MODE_STANDARD;
 297                 break;
 298         case I2C_SMBUS_BYTE:
 299                 len = 1;
 300                 buffer = &data->byte;
 301                 iface->cur_mode |= KW_I2C_MODE_STANDARD;
 302                 break;
 303         case I2C_SMBUS_BYTE_DATA:
 304                 len = 1;
 305                 buffer = &data->byte;
 306                 iface->cur_mode |= KW_I2C_MODE_STANDARDSUB;
 307                 break;
 308         case I2C_SMBUS_WORD_DATA:
 309                 len = 2;
 310                 cur_word = cpu_to_le16(data->word);
 311                 buffer = (u8 *)&cur_word;
 312                 iface->cur_mode |= KW_I2C_MODE_STANDARDSUB;
 313                 break;
 314         case I2C_SMBUS_BLOCK_DATA:
 315                 len = data->block[0];
 316                 buffer = &data->block[1];
 317                 iface->cur_mode |= KW_I2C_MODE_STANDARDSUB;
 318                 break;
 319         default:
 320                 return -1;
 321         }
 322
 323         /* Turn a standardsub read into a combined mode access */
 324         if (read_write == I2C_SMBUS_READ
 325             && (iface->cur_mode & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_STANDARDSUB) {
 326                 iface->cur_mode &= ~KW_I2C_MODE_MODE_MASK;
 327                 iface->cur_mode |= KW_I2C_MODE_COMBINED;
 328         }
 329
 330         /* Original driver had this limitation */
 331         if (len > 32)
 332                 len = 32;
 333
 334         if (pmac_low_i2c_lock(iface->node))
 335                 return -ENXIO;
 336
 337         pr_debug("chan: %d, addr: 0x%x, transfer len: %d, read: %d\n",
 338                 chan->chan_no, addr, len, read_write == I2C_SMBUS_READ);
 339
 340         iface->data = buffer;
 341         iface->datalen = len;
 342         iface->state = state_addr;
 343         iface->result = 0;
 344         iface->read_write = read_write;
 345
 346         /* Setup channel & clear pending irqs */
 347         write_reg(reg_isr, read_reg(reg_isr));
 348         write_reg(reg_mode, iface->cur_mode | (chan->chan_no << 4));
 349         write_reg(reg_status, 0);
 350
 351         /* Set up address and r/w bit */
 352         write_reg(reg_addr,
 353                 (addr << 1) | ((read_write == I2C_SMBUS_READ) ? 0x01 : 0x00));
 354
 355         /* Set up the sub address */
 356         if ((iface->cur_mode & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_STANDARDSUB
 357             || (iface->cur_mode & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_COMBINED)
 358                 write_reg(reg_subaddr, command);
 359
 360 #ifndef POLLED_MODE
 361         /* Arm timeout */
 362         iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 363         add_timer(&iface->timeout_timer);
 364 #endif
 365
 366         /* Start sending address & enable interrupt*/
 367         write_reg(reg_control, KW_I2C_CTL_XADDR);
 368         write_reg(reg_ier, KW_I2C_IRQ_MASK);
 369
 370 #ifdef POLLED_MODE
 371         pr_debug("using polled mode...\n");
 372         /* State machine, to turn into an interrupt handler */
 373         while(iface->state != state_idle) {
 374                 unsigned long flags;
 375
 376                 u8 isr = wait_interrupt(iface);
 377                 spin_lock_irqsave(&iface->lock, flags);
 378                 handle_interrupt(iface, isr);
 379                 spin_unlock_irqrestore(&iface->lock, flags);
 380         }
 381 #else /* POLLED_MODE */
 382         pr_debug("using interrupt mode...\n");
 383         wait_for_completion(&iface->complete);
 384 #endif /* POLLED_MODE */
 385
 386         rc = iface->result;
 387         pr_debug("transfer done, result: %d\n", rc);
 388
 389         if (rc == 0 && size == I2C_SMBUS_WORD_DATA && read_write == I2C_SMBUS_READ)
 390                 data->word = le16_to_cpu(cur_word);
 391
 392         /* Release sem */
 393         pmac_low_i2c_unlock(iface->node);
 394
 395         return rc;
 396 }
 397
 398 /*
 399  * Generic i2c master transfer entrypoint
 400  */
 401 static int
 402 keywest_xfer(   struct i2c_adapter *adap,
 403                 struct i2c_msg msgs[],
 404                 int num)
 405 {
 406         struct keywest_chan* chan = i2c_get_adapdata(adap);
 407         struct keywest_iface* iface = chan->iface;
 408         struct i2c_msg *pmsg;
 409         int i, completed;
 410         int rc = 0;
 411
 412         if (iface->state == state_dead)
 413                 return -ENXIO;
 414
 415         if (pmac_low_i2c_lock(iface->node))
 416                 return -ENXIO;
 417
 418         /* Set adapter to standard mode */
 419         iface->cur_mode &= ~KW_I2C_MODE_MODE_MASK;
 420         iface->cur_mode |= KW_I2C_MODE_STANDARD;
 421
 422         completed = 0;
 423         for (i = 0; rc >= 0 && i < num;) {
 424                 u8 addr;
 425
 426                 pmsg = &msgs[i++];
 427                 addr = pmsg->addr;
 428                 if (pmsg->flags & I2C_M_TEN) {
 429                         printk(KERN_ERR "i2c-keywest: 10 bits addr not supported !\n");
 430                         rc = -EINVAL;
 431                         break;
 432                 }
 433                 pr_debug("xfer: chan: %d, doing %s %d bytes to 0x%02x - %d of %d messages\n",
 434                      chan->chan_no,
 435                      pmsg->flags & I2C_M_RD ? "read" : "write",
 436                      pmsg->len, addr, i, num);
 437
 438                 /* Setup channel & clear pending irqs */
 439                 write_reg(reg_mode, iface->cur_mode | (chan->chan_no << 4));
 440                 write_reg(reg_isr, read_reg(reg_isr));
 441                 write_reg(reg_status, 0);
 442
 443                 iface->data = pmsg->buf;
 444                 iface->datalen = pmsg->len;
 445                 iface->state = state_addr;
 446                 iface->result = 0;
 447                 if (pmsg->flags & I2C_M_RD)
 448                         iface->read_write = I2C_SMBUS_READ;
 449                 else
 450                         iface->read_write = I2C_SMBUS_WRITE;
 451
 452                 /* Set up address and r/w bit */
 453                 if (pmsg->flags & I2C_M_REV_DIR_ADDR)
 454                         addr ^= 1;
 455                 write_reg(reg_addr,
 456                         (addr << 1) |
 457                         ((iface->read_write == I2C_SMBUS_READ) ? 0x01 : 0x00));
 458
 459 #ifndef POLLED_MODE
 460                 /* Arm timeout */
 461                 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 462                 add_timer(&iface->timeout_timer);
 463 #endif
 464
 465                 /* Start sending address & enable interrupt*/
 466                 write_reg(reg_ier, KW_I2C_IRQ_MASK);
 467                 write_reg(reg_control, KW_I2C_CTL_XADDR);
 468
 469 #ifdef POLLED_MODE
 470                 pr_debug("using polled mode...\n");
 471                 /* State machine, to turn into an interrupt handler */
 472                 while(iface->state != state_idle) {
 473                         u8 isr = wait_interrupt(iface);
 474                         handle_interrupt(iface, isr);
 475                 }
 476 #else /* POLLED_MODE */
 477                 pr_debug("using interrupt mode...\n");
 478                 wait_for_completion(&iface->complete);
 479 #endif /* POLLED_MODE */
 480
 481                 rc = iface->result;
 482                 if (rc == 0)
 483                         completed++;
 484                 pr_debug("transfer done, result: %d\n", rc);
 485         }
 486
 487         /* Release sem */
 488         pmac_low_i2c_unlock(iface->node);
 489
 490         return completed;
 491 }
 492
 493 static u32
 494 keywest_func(struct i2c_adapter * adapter)
 495 {
 496         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 497                I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 498                I2C_FUNC_SMBUS_BLOCK_DATA;
 499 }
 500
 501 /* For now, we only handle combined mode (smbus) */
 502 static struct i2c_algorithm keywest_algorithm = {
 503         .name           = "Keywest i2c",
 504         .id             = I2C_ALGO_SMBUS,
 505         .smbus_xfer     = keywest_smbus_xfer,
 506         .master_xfer    = keywest_xfer,
 507         .functionality  = keywest_func,
 508 };
 509
 510
 511 static int
 512 create_iface(struct device_node *np, struct device *dev)
 513 {
 514         unsigned long steps;
 515         unsigned bsteps, tsize, i, nchan, addroffset;
 516         struct keywest_iface* iface;
 517         u32 *psteps, *prate;
 518         int rc;
 519
 520         if (pmac_low_i2c_lock(np))
 521                 return -ENODEV;
 522
 523         psteps = (u32 *)get_property(np, "AAPL,address-step", NULL);
 524         steps = psteps ? (*psteps) : 0x10;
 525
 526         /* Hrm... maybe we can be smarter here */
 527         for (bsteps = 0; (steps & 0x01) == 0; bsteps++)
 528                 steps >>= 1;
 529
 530         if (np->parent->name[0] == 'u') {
 531                 nchan = 2;
 532                 addroffset = 3;
 533         } else {
 534                 addroffset = 0;
 535                 nchan = 1;
 536         }
 537
 538         tsize = sizeof(struct keywest_iface) +
 539                 (sizeof(struct keywest_chan) + 4) * nchan;
 540         iface = (struct keywest_iface *) kmalloc(tsize, GFP_KERNEL);
 541         if (iface == NULL) {
 542                 printk(KERN_ERR "i2c-keywest: can't allocate inteface !\n");
 543                 pmac_low_i2c_unlock(np);
 544                 return -ENOMEM;
 545         }
 546         memset(iface, 0, tsize);
 547         spin_lock_init(&iface->lock);
 548         init_completion(&iface->complete);
 549         iface->node = of_node_get(np);
 550         iface->bsteps = bsteps;
 551         iface->chan_count = nchan;
 552         iface->state = state_idle;
 553         iface->irq = np->intrs[0].line;
 554         iface->channels = (struct keywest_chan *)
 555                 (((unsigned long)(iface + 1) + 3UL) & ~3UL);
 556         iface->base = (unsigned long)ioremap(np->addrs[0].address + addroffset,
 557                                                 np->addrs[0].size);
 558         if (iface->base == 0) {
 559                 printk(KERN_ERR "i2c-keywest: can't map inteface !\n");
 560                 kfree(iface);
 561                 pmac_low_i2c_unlock(np);
 562                 return -ENOMEM;
 563         }
 564
 565 #ifndef POLLED_MODE
 566         init_timer(&iface->timeout_timer);
 567         iface->timeout_timer.function = keywest_timeout;
 568         iface->timeout_timer.data = (unsigned long)iface;
 569 #endif
 570
 571         /* Select interface rate */
 572         iface->cur_mode = KW_I2C_MODE_100KHZ;
 573         prate = (u32 *)get_property(np, "AAPL,i2c-rate", NULL);
 574         if (prate) switch(*prate) {
 575         case 100:
 576                 iface->cur_mode = KW_I2C_MODE_100KHZ;
 577                 break;
 578         case 50:
 579                 iface->cur_mode = KW_I2C_MODE_50KHZ;
 580                 break;
 581         case 25:
 582                 iface->cur_mode = KW_I2C_MODE_25KHZ;
 583                 break;
 584         default:
 585                 printk(KERN_WARNING "i2c-keywest: unknown rate %ldKhz, using 100KHz\n",
 586                        (long)*prate);
 587         }
 588
 589         /* Select standard mode by default */
 590         iface->cur_mode |= KW_I2C_MODE_STANDARD;
 591
 592         /* Write mode */
 593         write_reg(reg_mode, iface->cur_mode);
 594
 595         /* Switch interrupts off & clear them*/
 596         write_reg(reg_ier, 0x00);
 597         write_reg(reg_isr, KW_I2C_IRQ_MASK);
 598
 599 #ifndef POLLED_MODE
 600         /* Request chip interrupt */
 601         rc = request_irq(iface->irq, keywest_irq, SA_INTERRUPT, "keywest i2c", iface);
 602         if (rc) {
 603                 printk(KERN_ERR "i2c-keywest: can't get IRQ %d !\n", iface->irq);
 604                 iounmap((void *)iface->base);
 605                 kfree(iface);
 606                 pmac_low_i2c_unlock(np);
 607                 return -ENODEV;
 608         }
 609 #endif /* POLLED_MODE */
 610
 611         pmac_low_i2c_unlock(np);
 612         dev_set_drvdata(dev, iface);
 613
 614         for (i=0; i<nchan; i++) {
 615                 struct keywest_chan* chan = &iface->channels[i];
 616                 u8 addr;
 617
 618                 sprintf(chan->adapter.name, "%s %d", np->parent->name, i);
 619                 chan->iface = iface;
 620                 chan->chan_no = i;
 621                 chan->adapter.id = I2C_ALGO_SMBUS;
 622                 chan->adapter.algo = &keywest_algorithm;
 623                 chan->adapter.algo_data = NULL;
 624                 chan->adapter.client_register = NULL;
 625                 chan->adapter.client_unregister = NULL;
 626                 i2c_set_adapdata(&chan->adapter, chan);
 627                 chan->adapter.dev.parent = dev;
 628
 629                 rc = i2c_add_adapter(&chan->adapter);
 630                 if (rc) {
 631                         printk("i2c-keywest.c: Adapter %s registration failed\n",
 632                                 chan->adapter.name);
 633                         i2c_set_adapdata(&chan->adapter, NULL);
 634                 }
 635                 if (probe) {
 636                         printk("Probe: ");
 637                         for (addr = 0x00; addr <= 0x7f; addr++) {
 638                                 if (i2c_smbus_xfer(&chan->adapter,addr,
 639                                     0,0,0,I2C_SMBUS_QUICK,NULL) >= 0)
 640                                         printk("%02x ", addr);
 641                         }
 642                         printk("\n");
 643                 }
 644         }
 645
 646         printk(KERN_INFO "Found KeyWest i2c on \"%s\", %d channel%s, stepping: %d bits\n",
 647                 np->parent->name, nchan, nchan > 1 ? "s" : "", bsteps);
 648
 649         return 0;
 650 }
 651
 652 static int
 653 dispose_iface(struct device *dev)
 654 {
 655         struct keywest_iface *iface = dev_get_drvdata(dev);
 656         int i, rc;
 657
 658         /* Make sure we stop all activity */
 659         if (pmac_low_i2c_lock(iface->node))
 660                 return -ENODEV;
 661
 662 #ifndef POLLED_MODE
 663         spin_lock_irq(&iface->lock);
 664         while (iface->state != state_idle) {
 665                 spin_unlock_irq(&iface->lock);
 666                 set_task_state(current,TASK_UNINTERRUPTIBLE);
 667                 schedule_timeout(HZ/10);
 668                 spin_lock_irq(&iface->lock);
 669         }
 670 #endif /* POLLED_MODE */
 671         iface->state = state_dead;
 672 #ifndef POLLED_MODE
 673         spin_unlock_irq(&iface->lock);
 674         free_irq(iface->irq, iface);
 675 #endif /* POLLED_MODE */
 676
 677         pmac_low_i2c_unlock(iface->node);
 678
 679         /* Release all channels */
 680         for (i=0; i<iface->chan_count; i++) {
 681                 struct keywest_chan* chan = &iface->channels[i];
 682                 if (i2c_get_adapdata(&chan->adapter) == NULL)
 683                         continue;
 684                 rc = i2c_del_adapter(&chan->adapter);
 685                 i2c_set_adapdata(&chan->adapter, NULL);
 686                 /* We aren't that prepared to deal with this... */
 687                 if (rc)
 688                         printk("i2c-keywest.c: i2c_del_adapter failed, that's bad !\n");
 689         }
 690         iounmap((void *)iface->base);
 691         dev_set_drvdata(dev, NULL);
 692         of_node_put(iface->node);
 693         kfree(iface);
 694
 695         return 0;
 696 }
 697
 698 static int
 699 create_iface_macio(struct macio_dev* dev, const struct of_match *match)
 700 {
 701         return create_iface(dev->ofdev.node, &dev->ofdev.dev);
 702 }
 703
 704 static int
 705 dispose_iface_macio(struct macio_dev* dev)
 706 {
 707         return dispose_iface(&dev->ofdev.dev);
 708 }
 709
 710 static int
 711 create_iface_of_platform(struct of_device* dev, const struct of_match *match)
 712 {
 713         return create_iface(dev->node, &dev->dev);
 714 }
 715
 716 static int
 717 dispose_iface_of_platform(struct of_device* dev)
 718 {
 719         return dispose_iface(&dev->dev);
 720 }
 721
 722 static struct of_match i2c_keywest_match[] =
 723 {
 724         {
 725         .name           = OF_ANY_MATCH,
 726         .type           = "i2c",
 727         .compatible     = "keywest"
 728         },
 729         {},
 730 };
 731
 732 static struct macio_driver i2c_keywest_macio_driver =
 733 {
 734         .name           = "i2c-keywest",
 735         .match_table    = i2c_keywest_match,
 736         .probe          = create_iface_macio,
 737         .remove         = dispose_iface_macio
 738 };
 739
 740 static struct of_platform_driver i2c_keywest_of_platform_driver =
 741 {
 742         .name           = "i2c-keywest",
 743         .match_table    = i2c_keywest_match,
 744         .probe          = create_iface_of_platform,
 745         .remove         = dispose_iface_of_platform
 746 };
 747
 748 static int __init
 749 i2c_keywest_init(void)
 750 {
 751         of_register_driver(&i2c_keywest_of_platform_driver);
 752         macio_register_driver(&i2c_keywest_macio_driver);
 753
 754         return 0;
 755 }
 756
 757 static void __exit
 758 i2c_keywest_cleanup(void)
 759 {
 760         of_unregister_driver(&i2c_keywest_of_platform_driver);
 761         macio_unregister_driver(&i2c_keywest_macio_driver);
 762 }
 763
 764 module_init(i2c_keywest_init);
 765 module_exit(i2c_keywest_cleanup);