drivers/hwmon/i5k_amb.c

   1 /*
   2  * A hwmon driver for the Intel 5000 series chipset FB-DIMM AMB
   3  * temperature sensors
   4  * Copyright (C) 2007 IBM
   5  *
   6  * Author: Darrick J. Wong <djwong@us.ibm.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/jiffies.h>
  25 #include <linux/hwmon.h>
  26 #include <linux/hwmon-sysfs.h>
  27 #include <linux/err.h>
  28 #include <linux/mutex.h>
  29 #include <linux/delay.h>
  30 #include <linux/log2.h>
  31 #include <linux/pci.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/slab.h>
  34
  35 #define DRVNAME "i5k_amb"
  36
  37 #define I5K_REG_AMB_BASE_ADDR           0x48
  38 #define I5K_REG_AMB_LEN_ADDR            0x50
  39 #define I5K_REG_CHAN0_PRESENCE_ADDR     0x64
  40 #define I5K_REG_CHAN1_PRESENCE_ADDR     0x66
  41
  42 #define AMB_REG_TEMP_MIN_ADDR           0x80
  43 #define AMB_REG_TEMP_MID_ADDR           0x81
  44 #define AMB_REG_TEMP_MAX_ADDR           0x82
  45 #define AMB_REG_TEMP_STATUS_ADDR        0x84
  46 #define AMB_REG_TEMP_ADDR               0x85
  47
  48 #define AMB_CONFIG_SIZE                 2048
  49 #define AMB_FUNC_3_OFFSET               768
  50
  51 static unsigned long amb_reg_temp_status(unsigned int amb)
  52 {
  53         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_STATUS_ADDR +
  54                AMB_CONFIG_SIZE * amb;
  55 }
  56
  57 static unsigned long amb_reg_temp_min(unsigned int amb)
  58 {
  59         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MIN_ADDR +
  60                AMB_CONFIG_SIZE * amb;
  61 }
  62
  63 static unsigned long amb_reg_temp_mid(unsigned int amb)
  64 {
  65         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MID_ADDR +
  66                AMB_CONFIG_SIZE * amb;
  67 }
  68
  69 static unsigned long amb_reg_temp_max(unsigned int amb)
  70 {
  71         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_MAX_ADDR +
  72                AMB_CONFIG_SIZE * amb;
  73 }
  74
  75 static unsigned long amb_reg_temp(unsigned int amb)
  76 {
  77         return AMB_FUNC_3_OFFSET + AMB_REG_TEMP_ADDR +
  78                AMB_CONFIG_SIZE * amb;
  79 }
  80
  81 #define MAX_MEM_CHANNELS                4
  82 #define MAX_AMBS_PER_CHANNEL            16
  83 #define MAX_AMBS                        (MAX_MEM_CHANNELS * \
  84                                          MAX_AMBS_PER_CHANNEL)
  85 #define CHANNEL_SHIFT                   4
  86 #define DIMM_MASK                       0xF
  87 /*
  88  * Ugly hack: For some reason the highest bit is set if there
  89  * are _any_ DIMMs in the channel.  Attempting to read from
  90  * this "high-order" AMB results in a memory bus error, so
  91  * for now we'll just ignore that top bit, even though that
  92  * might prevent us from seeing the 16th DIMM in the channel.
  93  */
  94 #define REAL_MAX_AMBS_PER_CHANNEL       15
  95 #define KNOBS_PER_AMB                   6
  96
  97 static unsigned long amb_num_from_reg(unsigned int byte_num, unsigned int bit)
  98 {
  99         return byte_num * MAX_AMBS_PER_CHANNEL + bit;
 100 }
 101
 102 #define AMB_SYSFS_NAME_LEN              16
 103 struct i5k_device_attribute {
 104         struct sensor_device_attribute s_attr;
 105         char name[AMB_SYSFS_NAME_LEN];
 106 };
 107
 108 struct i5k_amb_data {
 109         struct device *hwmon_dev;
 110
 111         unsigned long amb_base;
 112         unsigned long amb_len;
 113         u16 amb_present[MAX_MEM_CHANNELS];
 114         void __iomem *amb_mmio;
 115         struct i5k_device_attribute *attrs;
 116         unsigned int num_attrs;
 117 };
 118
 119 static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
 120                          char *buf)
 121 {
 122         return sprintf(buf, "%s\n", DRVNAME);
 123 }
 124
 125
 126 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
 127
 128 static struct platform_device *amb_pdev;
 129
 130 static u8 amb_read_byte(struct i5k_amb_data *data, unsigned long offset)
 131 {
 132         return ioread8(data->amb_mmio + offset);
 133 }
 134
 135 static void amb_write_byte(struct i5k_amb_data *data, unsigned long offset,
 136                            u8 val)
 137 {
 138         iowrite8(val, data->amb_mmio + offset);
 139 }
 140
 141 static ssize_t show_amb_alarm(struct device *dev,
 142                              struct device_attribute *devattr,
 143                              char *buf)
 144 {
 145         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 146         struct i5k_amb_data *data = dev_get_drvdata(dev);
 147
 148         if (!(amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x20) &&
 149              (amb_read_byte(data, amb_reg_temp_status(attr->index)) & 0x8))
 150                 return sprintf(buf, "1\n");
 151         else
 152                 return sprintf(buf, "0\n");
 153 }
 154
 155 static ssize_t store_amb_min(struct device *dev,
 156                              struct device_attribute *devattr,
 157                              const char *buf,
 158                              size_t count)
 159 {
 160         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 161         struct i5k_amb_data *data = dev_get_drvdata(dev);
 162         unsigned long temp;
 163         int ret = kstrtoul(buf, 10, &temp);
 164         if (ret < 0)
 165                 return ret;
 166
 167         temp = temp / 500;
 168         if (temp > 255)
 169                 temp = 255;
 170
 171         amb_write_byte(data, amb_reg_temp_min(attr->index), temp);
 172         return count;
 173 }
 174
 175 static ssize_t store_amb_mid(struct device *dev,
 176                              struct device_attribute *devattr,
 177                              const char *buf,
 178                              size_t count)
 179 {
 180         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 181         struct i5k_amb_data *data = dev_get_drvdata(dev);
 182         unsigned long temp;
 183         int ret = kstrtoul(buf, 10, &temp);
 184         if (ret < 0)
 185                 return ret;
 186
 187         temp = temp / 500;
 188         if (temp > 255)
 189                 temp = 255;
 190
 191         amb_write_byte(data, amb_reg_temp_mid(attr->index), temp);
 192         return count;
 193 }
 194
 195 static ssize_t store_amb_max(struct device *dev,
 196                              struct device_attribute *devattr,
 197                              const char *buf,
 198                              size_t count)
 199 {
 200         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 201         struct i5k_amb_data *data = dev_get_drvdata(dev);
 202         unsigned long temp;
 203         int ret = kstrtoul(buf, 10, &temp);
 204         if (ret < 0)
 205                 return ret;
 206
 207         temp = temp / 500;
 208         if (temp > 255)
 209                 temp = 255;
 210
 211         amb_write_byte(data, amb_reg_temp_max(attr->index), temp);
 212         return count;
 213 }
 214
 215 static ssize_t show_amb_min(struct device *dev,
 216                              struct device_attribute *devattr,
 217                              char *buf)
 218 {
 219         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 220         struct i5k_amb_data *data = dev_get_drvdata(dev);
 221         return sprintf(buf, "%d\n",
 222                 500 * amb_read_byte(data, amb_reg_temp_min(attr->index)));
 223 }
 224
 225 static ssize_t show_amb_mid(struct device *dev,
 226                              struct device_attribute *devattr,
 227                              char *buf)
 228 {
 229         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 230         struct i5k_amb_data *data = dev_get_drvdata(dev);
 231         return sprintf(buf, "%d\n",
 232                 500 * amb_read_byte(data, amb_reg_temp_mid(attr->index)));
 233 }
 234
 235 static ssize_t show_amb_max(struct device *dev,
 236                              struct device_attribute *devattr,
 237                              char *buf)
 238 {
 239         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 240         struct i5k_amb_data *data = dev_get_drvdata(dev);
 241         return sprintf(buf, "%d\n",
 242                 500 * amb_read_byte(data, amb_reg_temp_max(attr->index)));
 243 }
 244
 245 static ssize_t show_amb_temp(struct device *dev,
 246                              struct device_attribute *devattr,
 247                              char *buf)
 248 {
 249         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 250         struct i5k_amb_data *data = dev_get_drvdata(dev);
 251         return sprintf(buf, "%d\n",
 252                 500 * amb_read_byte(data, amb_reg_temp(attr->index)));
 253 }
 254
 255 static ssize_t show_label(struct device *dev,
 256                           struct device_attribute *devattr,
 257                           char *buf)
 258 {
 259         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 260
 261         return sprintf(buf, "Ch. %d DIMM %d\n", attr->index >> CHANNEL_SHIFT,
 262                        attr->index & DIMM_MASK);
 263 }
 264
 265 static int __devinit i5k_amb_hwmon_init(struct platform_device *pdev)
 266 {
 267         int i, j, k, d = 0;
 268         u16 c;
 269         int res = 0;
 270         int num_ambs = 0;
 271         struct i5k_amb_data *data = platform_get_drvdata(pdev);
 272
 273         /* Count the number of AMBs found */
 274         /* ignore the high-order bit, see "Ugly hack" comment above */
 275         for (i = 0; i < MAX_MEM_CHANNELS; i++)
 276                 num_ambs += hweight16(data->amb_present[i] & 0x7fff);
 277
 278         /* Set up sysfs stuff */
 279         data->attrs = kzalloc(sizeof(*data->attrs) * num_ambs * KNOBS_PER_AMB,
 280                                 GFP_KERNEL);
 281         if (!data->attrs)
 282                 return -ENOMEM;
 283         data->num_attrs = 0;
 284
 285         for (i = 0; i < MAX_MEM_CHANNELS; i++) {
 286                 c = data->amb_present[i];
 287                 for (j = 0; j < REAL_MAX_AMBS_PER_CHANNEL; j++, c >>= 1) {
 288                         struct i5k_device_attribute *iattr;
 289
 290                         k = amb_num_from_reg(i, j);
 291                         if (!(c & 0x1))
 292                                 continue;
 293                         d++;
 294
 295                         /* sysfs label */
 296                         iattr = data->attrs + data->num_attrs;
 297                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 298                                  "temp%d_label", d);
 299                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 300                         iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
 301                         iattr->s_attr.dev_attr.show = show_label;
 302                         iattr->s_attr.index = k;
 303                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 304                         res = device_create_file(&pdev->dev,
 305                                                  &iattr->s_attr.dev_attr);
 306                         if (res)
 307                                 goto exit_remove;
 308                         data->num_attrs++;
 309
 310                         /* Temperature sysfs knob */
 311                         iattr = data->attrs + data->num_attrs;
 312                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 313                                  "temp%d_input", d);
 314                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 315                         iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
 316                         iattr->s_attr.dev_attr.show = show_amb_temp;
 317                         iattr->s_attr.index = k;
 318                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 319                         res = device_create_file(&pdev->dev,
 320                                                  &iattr->s_attr.dev_attr);
 321                         if (res)
 322                                 goto exit_remove;
 323                         data->num_attrs++;
 324
 325                         /* Temperature min sysfs knob */
 326                         iattr = data->attrs + data->num_attrs;
 327                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 328                                  "temp%d_min", d);
 329                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 330                         iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
 331                         iattr->s_attr.dev_attr.show = show_amb_min;
 332                         iattr->s_attr.dev_attr.store = store_amb_min;
 333                         iattr->s_attr.index = k;
 334                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 335                         res = device_create_file(&pdev->dev,
 336                                                  &iattr->s_attr.dev_attr);
 337                         if (res)
 338                                 goto exit_remove;
 339                         data->num_attrs++;
 340
 341                         /* Temperature mid sysfs knob */
 342                         iattr = data->attrs + data->num_attrs;
 343                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 344                                  "temp%d_mid", d);
 345                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 346                         iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
 347                         iattr->s_attr.dev_attr.show = show_amb_mid;
 348                         iattr->s_attr.dev_attr.store = store_amb_mid;
 349                         iattr->s_attr.index = k;
 350                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 351                         res = device_create_file(&pdev->dev,
 352                                                  &iattr->s_attr.dev_attr);
 353                         if (res)
 354                                 goto exit_remove;
 355                         data->num_attrs++;
 356
 357                         /* Temperature max sysfs knob */
 358                         iattr = data->attrs + data->num_attrs;
 359                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 360                                  "temp%d_max", d);
 361                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 362                         iattr->s_attr.dev_attr.attr.mode = S_IWUSR | S_IRUGO;
 363                         iattr->s_attr.dev_attr.show = show_amb_max;
 364                         iattr->s_attr.dev_attr.store = store_amb_max;
 365                         iattr->s_attr.index = k;
 366                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 367                         res = device_create_file(&pdev->dev,
 368                                                  &iattr->s_attr.dev_attr);
 369                         if (res)
 370                                 goto exit_remove;
 371                         data->num_attrs++;
 372
 373                         /* Temperature alarm sysfs knob */
 374                         iattr = data->attrs + data->num_attrs;
 375                         snprintf(iattr->name, AMB_SYSFS_NAME_LEN,
 376                                  "temp%d_alarm", d);
 377                         iattr->s_attr.dev_attr.attr.name = iattr->name;
 378                         iattr->s_attr.dev_attr.attr.mode = S_IRUGO;
 379                         iattr->s_attr.dev_attr.show = show_amb_alarm;
 380                         iattr->s_attr.index = k;
 381                         sysfs_attr_init(&iattr->s_attr.dev_attr.attr);
 382                         res = device_create_file(&pdev->dev,
 383                                                  &iattr->s_attr.dev_attr);
 384                         if (res)
 385                                 goto exit_remove;
 386                         data->num_attrs++;
 387                 }
 388         }
 389
 390         res = device_create_file(&pdev->dev, &dev_attr_name);
 391         if (res)
 392                 goto exit_remove;
 393
 394         data->hwmon_dev = hwmon_device_register(&pdev->dev);
 395         if (IS_ERR(data->hwmon_dev)) {
 396                 res = PTR_ERR(data->hwmon_dev);
 397                 goto exit_remove;
 398         }
 399
 400         return res;
 401
 402 exit_remove:
 403         device_remove_file(&pdev->dev, &dev_attr_name);
 404         for (i = 0; i < data->num_attrs; i++)
 405                 device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
 406         kfree(data->attrs);
 407
 408         return res;
 409 }
 410
 411 static int __devinit i5k_amb_add(void)
 412 {
 413         int res = -ENODEV;
 414
 415         /* only ever going to be one of these */
 416         amb_pdev = platform_device_alloc(DRVNAME, 0);
 417         if (!amb_pdev)
 418                 return -ENOMEM;
 419
 420         res = platform_device_add(amb_pdev);
 421         if (res)
 422                 goto err;
 423         return 0;
 424
 425 err:
 426         platform_device_put(amb_pdev);
 427         return res;
 428 }
 429
 430 static int __devinit i5k_find_amb_registers(struct i5k_amb_data *data,
 431                                             unsigned long devid)
 432 {
 433         struct pci_dev *pcidev;
 434         u32 val32;
 435         int res = -ENODEV;
 436
 437         /* Find AMB register memory space */
 438         pcidev = pci_get_device(PCI_VENDOR_ID_INTEL,
 439                                 devid,
 440                                 NULL);
 441         if (!pcidev)
 442                 return -ENODEV;
 443
 444         if (pci_read_config_dword(pcidev, I5K_REG_AMB_BASE_ADDR, &val32))
 445                 goto out;
 446         data->amb_base = val32;
 447
 448         if (pci_read_config_dword(pcidev, I5K_REG_AMB_LEN_ADDR, &val32))
 449                 goto out;
 450         data->amb_len = val32;
 451
 452         /* Is it big enough? */
 453         if (data->amb_len < AMB_CONFIG_SIZE * MAX_AMBS) {
 454                 dev_err(&pcidev->dev, "AMB region too small!\n");
 455                 goto out;
 456         }
 457
 458         res = 0;
 459 out:
 460         pci_dev_put(pcidev);
 461         return res;
 462 }
 463
 464 static int __devinit i5k_channel_probe(u16 *amb_present, unsigned long dev_id)
 465 {
 466         struct pci_dev *pcidev;
 467         u16 val16;
 468         int res = -ENODEV;
 469
 470         /* Copy the DIMM presence map for these two channels */
 471         pcidev = pci_get_device(PCI_VENDOR_ID_INTEL, dev_id, NULL);
 472         if (!pcidev)
 473                 return -ENODEV;
 474
 475         if (pci_read_config_word(pcidev, I5K_REG_CHAN0_PRESENCE_ADDR, &val16))
 476                 goto out;
 477         amb_present[0] = val16;
 478
 479         if (pci_read_config_word(pcidev, I5K_REG_CHAN1_PRESENCE_ADDR, &val16))
 480                 goto out;
 481         amb_present[1] = val16;
 482
 483         res = 0;
 484
 485 out:
 486         pci_dev_put(pcidev);
 487         return res;
 488 }
 489
 490 static struct {
 491         unsigned long err;
 492         unsigned long fbd0;
 493 } chipset_ids[] __devinitdata  = {
 494         { PCI_DEVICE_ID_INTEL_5000_ERR, PCI_DEVICE_ID_INTEL_5000_FBD0 },
 495         { PCI_DEVICE_ID_INTEL_5400_ERR, PCI_DEVICE_ID_INTEL_5400_FBD0 },
 496         { 0, 0 }
 497 };
 498
 499 #ifdef MODULE
 500 static struct pci_device_id i5k_amb_ids[] __devinitdata = {
 501         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5000_ERR) },
 502         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5400_ERR) },
 503         { 0, }
 504 };
 505 MODULE_DEVICE_TABLE(pci, i5k_amb_ids);
 506 #endif
 507
 508 static int __devinit i5k_amb_probe(struct platform_device *pdev)
 509 {
 510         struct i5k_amb_data *data;
 511         struct resource *reso;
 512         int i, res;
 513
 514         data = kzalloc(sizeof(*data), GFP_KERNEL);
 515         if (!data)
 516                 return -ENOMEM;
 517
 518         /* Figure out where the AMB registers live */
 519         i = 0;
 520         do {
 521                 res = i5k_find_amb_registers(data, chipset_ids[i].err);
 522                 if (res == 0)
 523                         break;
 524                 i++;
 525         } while (chipset_ids[i].err);
 526
 527         if (res)
 528                 goto err;
 529
 530         /* Copy the DIMM presence map for the first two channels */
 531         res = i5k_channel_probe(&data->amb_present[0], chipset_ids[i].fbd0);
 532         if (res)
 533                 goto err;
 534
 535         /* Copy the DIMM presence map for the optional second two channels */
 536         i5k_channel_probe(&data->amb_present[2], chipset_ids[i].fbd0 + 1);
 537
 538         /* Set up resource regions */
 539         reso = request_mem_region(data->amb_base, data->amb_len, DRVNAME);
 540         if (!reso) {
 541                 res = -EBUSY;
 542                 goto err;
 543         }
 544
 545         data->amb_mmio = ioremap_nocache(data->amb_base, data->amb_len);
 546         if (!data->amb_mmio) {
 547                 res = -EBUSY;
 548                 goto err_map_failed;
 549         }
 550
 551         platform_set_drvdata(pdev, data);
 552
 553         res = i5k_amb_hwmon_init(pdev);
 554         if (res)
 555                 goto err_init_failed;
 556
 557         return res;
 558
 559 err_init_failed:
 560         iounmap(data->amb_mmio);
 561         platform_set_drvdata(pdev, NULL);
 562 err_map_failed:
 563         release_mem_region(data->amb_base, data->amb_len);
 564 err:
 565         kfree(data);
 566         return res;
 567 }
 568
 569 static int __devexit i5k_amb_remove(struct platform_device *pdev)
 570 {
 571         int i;
 572         struct i5k_amb_data *data = platform_get_drvdata(pdev);
 573
 574         hwmon_device_unregister(data->hwmon_dev);
 575         device_remove_file(&pdev->dev, &dev_attr_name);
 576         for (i = 0; i < data->num_attrs; i++)
 577                 device_remove_file(&pdev->dev, &data->attrs[i].s_attr.dev_attr);
 578         kfree(data->attrs);
 579         iounmap(data->amb_mmio);
 580         release_mem_region(data->amb_base, data->amb_len);
 581         platform_set_drvdata(pdev, NULL);
 582         kfree(data);
 583         return 0;
 584 }
 585
 586 static struct platform_driver i5k_amb_driver = {
 587         .driver = {
 588                 .owner = THIS_MODULE,
 589                 .name = DRVNAME,
 590         },
 591         .probe = i5k_amb_probe,
 592         .remove = __devexit_p(i5k_amb_remove),
 593 };
 594
 595 static int __init i5k_amb_init(void)
 596 {
 597         int res;
 598
 599         res = platform_driver_register(&i5k_amb_driver);
 600         if (res)
 601                 return res;
 602
 603         res = i5k_amb_add();
 604         if (res)
 605                 platform_driver_unregister(&i5k_amb_driver);
 606
 607         return res;
 608 }
 609
 610 static void __exit i5k_amb_exit(void)
 611 {
 612         platform_device_unregister(amb_pdev);
 613         platform_driver_unregister(&i5k_amb_driver);
 614 }
 615
 616 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
 617 MODULE_DESCRIPTION("Intel 5000 chipset FB-DIMM AMB temperature sensor");
 618 MODULE_LICENSE("GPL");
 619
 620 module_init(i5k_amb_init);
 621 module_exit(i5k_amb_exit);