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/kernel.h>
  52 #include <linux/ioport.h>
  53 #include <linux/pci.h>
  54 #include <linux/types.h>
  55 #include <linux/delay.h>
  56 #include <linux/i2c.h>
  57 #include <linux/init.h>
  58 #include <linux/mm.h>
  59 #include <linux/timer.h>
  60 #include <linux/spinlock.h>
  61 #include <linux/completion.h>
  62 #include <linux/interrupt.h>
  63
  64 #include <asm/io.h>
  65 #include <asm/prom.h>
  66 #include <asm/machdep.h>
  67 #include <asm/pmac_feature.h>
  68 #include <asm/pmac_low_i2c.h>
  69
  70 #include "i2c-keywest.h"
  71
  72 #undef POLLED_MODE
  73
  74 /* Some debug macros */
  75 #define WRONG_STATE(name) do {\
  76                 pr_debug("KW: wrong state. Got %s, state: %s (isr: %02x)\n", \
  77                          name, __kw_state_names[iface->state], isr);    \
  78         } while(0)
  79
  80 #ifdef DEBUG
  81 static const char *__kw_state_names[] = {
  82         "state_idle",
  83         "state_addr",
  84         "state_read",
  85         "state_write",
  86         "state_stop",
  87         "state_dead"
  88 };
  89 #endif /* DEBUG */
  90
  91 static int probe;
  92
  93 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
  94 MODULE_DESCRIPTION("I2C driver for Apple's Keywest");
  95 MODULE_LICENSE("GPL");
  96 module_param(probe, bool, 0);
  97
  98 #ifdef POLLED_MODE
  99 /* Don't schedule, the g5 fan controller is too
 100  * timing sensitive
 101  */
 102 static u8
 103 wait_interrupt(struct keywest_iface* iface)
 104 {
 105         int i;
 106         u8 isr;
 107
 108         for (i = 0; i < 200000; i++) {
 109                 isr = read_reg(reg_isr) & KW_I2C_IRQ_MASK;
 110                 if (isr != 0)
 111                         return isr;
 112                 udelay(10);
 113         }
 114         return isr;
 115 }
 116 #endif /* POLLED_MODE */
 117
 118 static void
 119 do_stop(struct keywest_iface* iface, int result)
 120 {
 121         write_reg(reg_control, KW_I2C_CTL_STOP);
 122         iface->state = state_stop;
 123         iface->result = result;
 124 }
 125
 126 /* Main state machine for standard & standard sub mode */
 127 static void
 128 handle_interrupt(struct keywest_iface *iface, u8 isr)
 129 {
 130         int ack;
 131
 132         if (isr == 0) {
 133                 if (iface->state != state_stop) {
 134                         pr_debug("KW: Timeout !\n");
 135                         do_stop(iface, -EIO);
 136                 }
 137                 if (iface->state == state_stop) {
 138                         ack = read_reg(reg_status);
 139                         if (!(ack & KW_I2C_STAT_BUSY)) {
 140                                 iface->state = state_idle;
 141                                 write_reg(reg_ier, 0x00);
 142 #ifndef POLLED_MODE
 143                                 complete(&iface->complete);
 144 #endif /* POLLED_MODE */
 145                         }
 146                 }
 147                 return;
 148         }
 149
 150         if (isr & KW_I2C_IRQ_ADDR) {
 151                 ack = read_reg(reg_status);
 152                 if (iface->state != state_addr) {
 153                         write_reg(reg_isr, KW_I2C_IRQ_ADDR);
 154                         WRONG_STATE("KW_I2C_IRQ_ADDR");
 155                         do_stop(iface, -EIO);
 156                         return;
 157                 }
 158                 if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
 159                         iface->state = state_stop;
 160                         iface->result = -ENODEV;
 161                         pr_debug("KW: NAK on address\n");
 162                 } else {
 163                         /* Handle rw "quick" mode */
 164                         if (iface->datalen == 0) {
 165                                 do_stop(iface, 0);
 166                         } else if (iface->read_write == I2C_SMBUS_READ) {
 167                                 iface->state = state_read;
 168                                 if (iface->datalen > 1)
 169                                         write_reg(reg_control, KW_I2C_CTL_AAK);
 170                         } else {
 171                                 iface->state = state_write;
 172                                 write_reg(reg_data, *(iface->data++));
 173                                 iface->datalen--;
 174                         }
 175                 }
 176                 write_reg(reg_isr, KW_I2C_IRQ_ADDR);
 177         }
 178
 179         if (isr & KW_I2C_IRQ_DATA) {
 180                 if (iface->state == state_read) {
 181                         *(iface->data++) = read_reg(reg_data);
 182                         write_reg(reg_isr, KW_I2C_IRQ_DATA);
 183                         iface->datalen--;
 184                         if (iface->datalen == 0)
 185                                 iface->state = state_stop;
 186                         else if (iface->datalen == 1)
 187                                 write_reg(reg_control, 0);
 188                 } else if (iface->state == state_write) {
 189                         /* Check ack status */
 190                         ack = read_reg(reg_status);
 191                         if ((ack & KW_I2C_STAT_LAST_AAK) == 0) {
 192                                 pr_debug("KW: nack on data write (%x): %x\n",
 193                                     iface->data[-1], ack);
 194                                 do_stop(iface, -EIO);
 195                         } else if (iface->datalen) {
 196                                 write_reg(reg_data, *(iface->data++));
 197                                 iface->datalen--;
 198                         } else {
 199                                 write_reg(reg_control, KW_I2C_CTL_STOP);
 200                                 iface->state = state_stop;
 201                                 iface->result = 0;
 202                         }
 203                         write_reg(reg_isr, KW_I2C_IRQ_DATA);
 204                 } else {
 205                         write_reg(reg_isr, KW_I2C_IRQ_DATA);
 206                         WRONG_STATE("KW_I2C_IRQ_DATA");
 207                         if (iface->state != state_stop)
 208                                 do_stop(iface, -EIO);
 209                 }
 210         }
 211
 212         if (isr & KW_I2C_IRQ_STOP) {
 213                 write_reg(reg_isr, KW_I2C_IRQ_STOP);
 214                 if (iface->state != state_stop) {
 215                         WRONG_STATE("KW_I2C_IRQ_STOP");
 216                         iface->result = -EIO;
 217                 }
 218                 iface->state = state_idle;
 219                 write_reg(reg_ier, 0x00);
 220 #ifndef POLLED_MODE
 221                 complete(&iface->complete);
 222 #endif /* POLLED_MODE */
 223         }
 224
 225         if (isr & KW_I2C_IRQ_START)
 226                 write_reg(reg_isr, KW_I2C_IRQ_START);
 227 }
 228
 229 #ifndef POLLED_MODE
 230
 231 /* Interrupt handler */
 232 static irqreturn_t
 233 keywest_irq(int irq, void *dev_id, struct pt_regs *regs)
 234 {
 235         struct keywest_iface *iface = (struct keywest_iface *)dev_id;
 236         unsigned long flags;
 237
 238         spin_lock_irqsave(&iface->lock, flags);
 239         del_timer(&iface->timeout_timer);
 240         handle_interrupt(iface, read_reg(reg_isr));
 241         if (iface->state != state_idle) {
 242                 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 243                 add_timer(&iface->timeout_timer);
 244         }
 245         spin_unlock_irqrestore(&iface->lock, flags);
 246         return IRQ_HANDLED;
 247 }
 248
 249 static void
 250 keywest_timeout(unsigned long data)
 251 {
 252         struct keywest_iface *iface = (struct keywest_iface *)data;
 253         unsigned long flags;
 254
 255         pr_debug("timeout !\n");
 256         spin_lock_irqsave(&iface->lock, flags);
 257         handle_interrupt(iface, read_reg(reg_isr));
 258         if (iface->state != state_idle) {
 259                 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 260                 add_timer(&iface->timeout_timer);
 261         }
 262         spin_unlock_irqrestore(&iface->lock, flags);
 263 }
 264
 265 #endif /* POLLED_MODE */
 266
 267 /*
 268  * SMBUS-type transfer entrypoint
 269  */
 270 static s32
 271 keywest_smbus_xfer(     struct i2c_adapter*     adap,
 272                         u16                     addr,
 273                         unsigned short          flags,
 274                         char                    read_write,
 275                         u8                      command,
 276                         int                     size,
 277                         union i2c_smbus_data*   data)
 278 {
 279         struct keywest_chan* chan = i2c_get_adapdata(adap);
 280         struct keywest_iface* iface = chan->iface;
 281         int len;
 282         u8* buffer;
 283         u16 cur_word;
 284         int rc = 0;
 285
 286         if (iface->state == state_dead)
 287                 return -ENXIO;
 288
 289         /* Prepare datas & select mode */
 290         iface->cur_mode &= ~KW_I2C_MODE_MODE_MASK;
 291         switch (size) {
 292         case I2C_SMBUS_QUICK:
 293                 len = 0;
 294                 buffer = NULL;
 295                 iface->cur_mode |= KW_I2C_MODE_STANDARD;
 296                 break;
 297         case I2C_SMBUS_BYTE:
 298                 len = 1;
 299                 buffer = &data->byte;
 300                 iface->cur_mode |= KW_I2C_MODE_STANDARD;
 301                 break;
 302         case I2C_SMBUS_BYTE_DATA:
 303                 len = 1;
 304                 buffer = &data->byte;
 305                 iface->cur_mode |= KW_I2C_MODE_STANDARDSUB;
 306                 break;
 307         case I2C_SMBUS_WORD_DATA:
 308                 len = 2;
 309                 cur_word = cpu_to_le16(data->word);
 310                 buffer = (u8 *)&cur_word;
 311                 iface->cur_mode |= KW_I2C_MODE_STANDARDSUB;
 312                 break;
 313         case I2C_SMBUS_BLOCK_DATA:
 314                 len = data->block[0];
 315                 buffer = &data->block[1];
 316                 iface->cur_mode |= KW_I2C_MODE_STANDARDSUB;
 317                 break;
 318         default:
 319                 return -1;
 320         }
 321
 322         /* Turn a standardsub read into a combined mode access */
 323         if (read_write == I2C_SMBUS_READ
 324             && (iface->cur_mode & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_STANDARDSUB) {
 325                 iface->cur_mode &= ~KW_I2C_MODE_MODE_MASK;
 326                 iface->cur_mode |= KW_I2C_MODE_COMBINED;
 327         }
 328
 329         /* Original driver had this limitation */
 330         if (len > 32)
 331                 len = 32;
 332
 333         if (pmac_low_i2c_lock(iface->node))
 334                 return -ENXIO;
 335
 336         pr_debug("chan: %d, addr: 0x%x, transfer len: %d, read: %d\n",
 337                 chan->chan_no, addr, len, read_write == I2C_SMBUS_READ);
 338
 339         iface->data = buffer;
 340         iface->datalen = len;
 341         iface->state = state_addr;
 342         iface->result = 0;
 343         iface->read_write = read_write;
 344
 345         /* Setup channel & clear pending irqs */
 346         write_reg(reg_isr, read_reg(reg_isr));
 347         write_reg(reg_mode, iface->cur_mode | (chan->chan_no << 4));
 348         write_reg(reg_status, 0);
 349
 350         /* Set up address and r/w bit */
 351         write_reg(reg_addr,
 352                 (addr << 1) | ((read_write == I2C_SMBUS_READ) ? 0x01 : 0x00));
 353
 354         /* Set up the sub address */
 355         if ((iface->cur_mode & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_STANDARDSUB
 356             || (iface->cur_mode & KW_I2C_MODE_MODE_MASK) == KW_I2C_MODE_COMBINED)
 357                 write_reg(reg_subaddr, command);
 358
 359 #ifndef POLLED_MODE
 360         /* Arm timeout */
 361         iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 362         add_timer(&iface->timeout_timer);
 363 #endif
 364
 365         /* Start sending address & enable interrupt*/
 366         write_reg(reg_control, KW_I2C_CTL_XADDR);
 367         write_reg(reg_ier, KW_I2C_IRQ_MASK);
 368
 369 #ifdef POLLED_MODE
 370         pr_debug("using polled mode...\n");
 371         /* State machine, to turn into an interrupt handler */
 372         while(iface->state != state_idle) {
 373                 unsigned long flags;
 374
 375                 u8 isr = wait_interrupt(iface);
 376                 spin_lock_irqsave(&iface->lock, flags);
 377                 handle_interrupt(iface, isr);
 378                 spin_unlock_irqrestore(&iface->lock, flags);
 379         }
 380 #else /* POLLED_MODE */
 381         pr_debug("using interrupt mode...\n");
 382         wait_for_completion(&iface->complete);
 383 #endif /* POLLED_MODE */
 384
 385         rc = iface->result;
 386         pr_debug("transfer done, result: %d\n", rc);
 387
 388         if (rc == 0 && size == I2C_SMBUS_WORD_DATA && read_write == I2C_SMBUS_READ)
 389                 data->word = le16_to_cpu(cur_word);
 390
 391         /* Release sem */
 392         pmac_low_i2c_unlock(iface->node);
 393
 394         return rc;
 395 }
 396
 397 /*
 398  * Generic i2c master transfer entrypoint
 399  */
 400 static int
 401 keywest_xfer(   struct i2c_adapter *adap,
 402                 struct i2c_msg *msgs,
 403                 int num)
 404 {
 405         struct keywest_chan* chan = i2c_get_adapdata(adap);
 406         struct keywest_iface* iface = chan->iface;
 407         struct i2c_msg *pmsg;
 408         int i, completed;
 409         int rc = 0;
 410
 411         if (iface->state == state_dead)
 412                 return -ENXIO;
 413
 414         if (pmac_low_i2c_lock(iface->node))
 415                 return -ENXIO;
 416
 417         /* Set adapter to standard mode */
 418         iface->cur_mode &= ~KW_I2C_MODE_MODE_MASK;
 419         iface->cur_mode |= KW_I2C_MODE_STANDARD;
 420
 421         completed = 0;
 422         for (i = 0; rc >= 0 && i < num;) {
 423                 u8 addr;
 424
 425                 pmsg = &msgs[i++];
 426                 addr = pmsg->addr;
 427                 if (pmsg->flags & I2C_M_TEN) {
 428                         printk(KERN_ERR "i2c-keywest: 10 bits addr not supported !\n");
 429                         rc = -EINVAL;
 430                         break;
 431                 }
 432                 pr_debug("xfer: chan: %d, doing %s %d bytes to 0x%02x - %d of %d messages\n",
 433                      chan->chan_no,
 434                      pmsg->flags & I2C_M_RD ? "read" : "write",
 435                      pmsg->len, addr, i, num);
 436
 437                 /* Setup channel & clear pending irqs */
 438                 write_reg(reg_mode, iface->cur_mode | (chan->chan_no << 4));
 439                 write_reg(reg_isr, read_reg(reg_isr));
 440                 write_reg(reg_status, 0);
 441
 442                 iface->data = pmsg->buf;
 443                 iface->datalen = pmsg->len;
 444                 iface->state = state_addr;
 445                 iface->result = 0;
 446                 if (pmsg->flags & I2C_M_RD)
 447                         iface->read_write = I2C_SMBUS_READ;
 448                 else
 449                         iface->read_write = I2C_SMBUS_WRITE;
 450
 451                 /* Set up address and r/w bit */
 452                 if (pmsg->flags & I2C_M_REV_DIR_ADDR)
 453                         addr ^= 1;
 454                 write_reg(reg_addr,
 455                         (addr << 1) |
 456                         ((iface->read_write == I2C_SMBUS_READ) ? 0x01 : 0x00));
 457
 458 #ifndef POLLED_MODE
 459                 /* Arm timeout */
 460                 iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
 461                 add_timer(&iface->timeout_timer);
 462 #endif
 463
 464                 /* Start sending address & enable interrupt*/
 465                 write_reg(reg_ier, KW_I2C_IRQ_MASK);
 466                 write_reg(reg_control, KW_I2C_CTL_XADDR);
 467
 468 #ifdef POLLED_MODE
 469                 pr_debug("using polled mode...\n");
 470                 /* State machine, to turn into an interrupt handler */
 471                 while(iface->state != state_idle) {
 472                         u8 isr = wait_interrupt(iface);
 473                         handle_interrupt(iface, isr);
 474                 }
 475 #else /* POLLED_MODE */
 476                 pr_debug("using interrupt mode...\n");
 477                 wait_for_completion(&iface->complete);
 478 #endif /* POLLED_MODE */
 479
 480                 rc = iface->result;
 481                 if (rc == 0)
 482                         completed++;
 483                 pr_debug("transfer done, result: %d\n", rc);
 484         }
 485
 486         /* Release sem */
 487         pmac_low_i2c_unlock(iface->node);
 488
 489         return completed;
 490 }
 491
 492 static u32
 493 keywest_func(struct i2c_adapter * adapter)
 494 {
 495         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 496                I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 497                I2C_FUNC_SMBUS_BLOCK_DATA;
 498 }
 499
 500 /* For now, we only handle combined mode (smbus) */
 501 static struct i2c_algorithm keywest_algorithm = {
 502         .name           = "Keywest i2c",
 503         .id             = I2C_ALGO_SMBUS,
 504         .smbus_xfer     = keywest_smbus_xfer,
 505         .master_xfer    = keywest_xfer,
 506         .functionality  = keywest_func,
 507 };
 508
 509
 510 static int
 511 create_iface(struct device_node *np, struct device *dev)
 512 {
 513         unsigned long steps;
 514         unsigned bsteps, tsize, i, nchan, addroffset;
 515         struct keywest_iface* iface;
 516         u32 *psteps, *prate;
 517         int rc;
 518
 519         if (np->n_intrs < 1 || np->n_addrs < 1) {
 520                 printk(KERN_ERR "%s: Missing interrupt or address !\n",
 521                        np->full_name);
 522                 return -ENODEV;
 523         }
 524         if (pmac_low_i2c_lock(np))
 525                 return -ENODEV;
 526
 527         psteps = (u32 *)get_property(np, "AAPL,address-step", NULL);
 528         steps = psteps ? (*psteps) : 0x10;
 529
 530         /* Hrm... maybe we can be smarter here */
 531         for (bsteps = 0; (steps & 0x01) == 0; bsteps++)
 532                 steps >>= 1;
 533
 534         if (np->parent->name[0] == 'u') {
 535                 nchan = 2;
 536                 addroffset = 3;
 537         } else {
 538                 addroffset = 0;
 539                 nchan = 1;
 540         }
 541
 542         tsize = sizeof(struct keywest_iface) +
 543                 (sizeof(struct keywest_chan) + 4) * nchan;
 544         iface = (struct keywest_iface *) kmalloc(tsize, GFP_KERNEL);
 545         if (iface == NULL) {
 546                 printk(KERN_ERR "i2c-keywest: can't allocate inteface !\n");
 547                 pmac_low_i2c_unlock(np);
 548                 return -ENOMEM;
 549         }
 550         memset(iface, 0, tsize);
 551         spin_lock_init(&iface->lock);
 552         init_completion(&iface->complete);
 553         iface->node = of_node_get(np);
 554         iface->bsteps = bsteps;
 555         iface->chan_count = nchan;
 556         iface->state = state_idle;
 557         iface->irq = np->intrs[0].line;
 558         iface->channels = (struct keywest_chan *)
 559                 (((unsigned long)(iface + 1) + 3UL) & ~3UL);
 560         iface->base = ioremap(np->addrs[0].address + addroffset,
 561                                                 np->addrs[0].size);
 562         if (!iface->base) {
 563                 printk(KERN_ERR "i2c-keywest: can't map inteface !\n");
 564                 kfree(iface);
 565                 pmac_low_i2c_unlock(np);
 566                 return -ENOMEM;
 567         }
 568
 569 #ifndef POLLED_MODE
 570         init_timer(&iface->timeout_timer);
 571         iface->timeout_timer.function = keywest_timeout;
 572         iface->timeout_timer.data = (unsigned long)iface;
 573 #endif
 574
 575         /* Select interface rate */
 576         iface->cur_mode = KW_I2C_MODE_100KHZ;
 577         prate = (u32 *)get_property(np, "AAPL,i2c-rate", NULL);
 578         if (prate) switch(*prate) {
 579         case 100:
 580                 iface->cur_mode = KW_I2C_MODE_100KHZ;
 581                 break;
 582         case 50:
 583                 iface->cur_mode = KW_I2C_MODE_50KHZ;
 584                 break;
 585         case 25:
 586                 iface->cur_mode = KW_I2C_MODE_25KHZ;
 587                 break;
 588         default:
 589                 printk(KERN_WARNING "i2c-keywest: unknown rate %ldKhz, using 100KHz\n",
 590                        (long)*prate);
 591         }
 592
 593         /* Select standard mode by default */
 594         iface->cur_mode |= KW_I2C_MODE_STANDARD;
 595
 596         /* Write mode */
 597         write_reg(reg_mode, iface->cur_mode);
 598
 599         /* Switch interrupts off & clear them*/
 600         write_reg(reg_ier, 0x00);
 601         write_reg(reg_isr, KW_I2C_IRQ_MASK);
 602
 603 #ifndef POLLED_MODE
 604         /* Request chip interrupt */
 605         rc = request_irq(iface->irq, keywest_irq, SA_INTERRUPT, "keywest i2c", iface);
 606         if (rc) {
 607                 printk(KERN_ERR "i2c-keywest: can't get IRQ %d !\n", iface->irq);
 608                 iounmap(iface->base);
 609                 kfree(iface);
 610                 pmac_low_i2c_unlock(np);
 611                 return -ENODEV;
 612         }
 613 #endif /* POLLED_MODE */
 614
 615         pmac_low_i2c_unlock(np);
 616         dev_set_drvdata(dev, iface);
 617
 618         for (i=0; i<nchan; i++) {
 619                 struct keywest_chan* chan = &iface->channels[i];
 620                 u8 addr;
 621
 622                 sprintf(chan->adapter.name, "%s %d", np->parent->name, i);
 623                 chan->iface = iface;
 624                 chan->chan_no = i;
 625                 chan->adapter.id = I2C_ALGO_SMBUS;
 626                 chan->adapter.algo = &keywest_algorithm;
 627                 chan->adapter.algo_data = NULL;
 628                 chan->adapter.client_register = NULL;
 629                 chan->adapter.client_unregister = NULL;
 630                 i2c_set_adapdata(&chan->adapter, chan);
 631                 chan->adapter.dev.parent = dev;
 632
 633                 rc = i2c_add_adapter(&chan->adapter);
 634                 if (rc) {
 635                         printk("i2c-keywest.c: Adapter %s registration failed\n",
 636                                 chan->adapter.name);
 637                         i2c_set_adapdata(&chan->adapter, NULL);
 638                 }
 639                 if (probe) {
 640                         printk("Probe: ");
 641                         for (addr = 0x00; addr <= 0x7f; addr++) {
 642                                 if (i2c_smbus_xfer(&chan->adapter,addr,
 643                                     0,0,0,I2C_SMBUS_QUICK,NULL) >= 0)
 644                                         printk("%02x ", addr);
 645                         }
 646                         printk("\n");
 647                 }
 648         }
 649
 650         printk(KERN_INFO "Found KeyWest i2c on \"%s\", %d channel%s, stepping: %d bits\n",
 651                 np->parent->name, nchan, nchan > 1 ? "s" : "", bsteps);
 652
 653         return 0;
 654 }
 655
 656 static int
 657 dispose_iface(struct device *dev)
 658 {
 659         struct keywest_iface *iface = dev_get_drvdata(dev);
 660         int i, rc;
 661
 662         /* Make sure we stop all activity */
 663         if (pmac_low_i2c_lock(iface->node))
 664                 return -ENODEV;
 665
 666 #ifndef POLLED_MODE
 667         spin_lock_irq(&iface->lock);
 668         while (iface->state != state_idle) {
 669                 spin_unlock_irq(&iface->lock);
 670                 msleep(100);
 671                 spin_lock_irq(&iface->lock);
 672         }
 673 #endif /* POLLED_MODE */
 674         iface->state = state_dead;
 675 #ifndef POLLED_MODE
 676         spin_unlock_irq(&iface->lock);
 677         free_irq(iface->irq, iface);
 678 #endif /* POLLED_MODE */
 679
 680         pmac_low_i2c_unlock(iface->node);
 681
 682         /* Release all channels */
 683         for (i=0; i<iface->chan_count; i++) {
 684                 struct keywest_chan* chan = &iface->channels[i];
 685                 if (i2c_get_adapdata(&chan->adapter) == NULL)
 686                         continue;
 687                 rc = i2c_del_adapter(&chan->adapter);
 688                 i2c_set_adapdata(&chan->adapter, NULL);
 689                 /* We aren't that prepared to deal with this... */
 690                 if (rc)
 691                         printk("i2c-keywest.c: i2c_del_adapter failed, that's bad !\n");
 692         }
 693         iounmap(iface->base);
 694         dev_set_drvdata(dev, NULL);
 695         of_node_put(iface->node);
 696         kfree(iface);
 697
 698         return 0;
 699 }
 700
 701 static int
 702 create_iface_macio(struct macio_dev* dev, const struct of_match *match)
 703 {
 704         return create_iface(dev->ofdev.node, &dev->ofdev.dev);
 705 }
 706
 707 static int
 708 dispose_iface_macio(struct macio_dev* dev)
 709 {
 710         return dispose_iface(&dev->ofdev.dev);
 711 }
 712
 713 static int
 714 create_iface_of_platform(struct of_device* dev, const struct of_match *match)
 715 {
 716         return create_iface(dev->node, &dev->dev);
 717 }
 718
 719 static int
 720 dispose_iface_of_platform(struct of_device* dev)
 721 {
 722         return dispose_iface(&dev->dev);
 723 }
 724
 725 static struct of_match i2c_keywest_match[] =
 726 {
 727         {
 728         .name           = OF_ANY_MATCH,
 729         .type           = "i2c",
 730         .compatible     = "keywest"
 731         },
 732         {},
 733 };
 734
 735 static struct macio_driver i2c_keywest_macio_driver =
 736 {
 737         .name           = "i2c-keywest",
 738         .match_table    = i2c_keywest_match,
 739         .probe          = create_iface_macio,
 740         .remove         = dispose_iface_macio
 741 };
 742
 743 static struct of_platform_driver i2c_keywest_of_platform_driver =
 744 {
 745         .name           = "i2c-keywest",
 746         .match_table    = i2c_keywest_match,
 747         .probe          = create_iface_of_platform,
 748         .remove         = dispose_iface_of_platform
 749 };
 750
 751 static int __init
 752 i2c_keywest_init(void)
 753 {
 754         of_register_driver(&i2c_keywest_of_platform_driver);
 755         macio_register_driver(&i2c_keywest_macio_driver);
 756
 757         return 0;
 758 }
 759
 760 static void __exit
 761 i2c_keywest_cleanup(void)
 762 {
 763         of_unregister_driver(&i2c_keywest_of_platform_driver);
 764         macio_unregister_driver(&i2c_keywest_macio_driver);
 765 }
 766
 767 module_init(i2c_keywest_init);
 768 module_exit(i2c_keywest_cleanup);