drivers/misc/ics932s401.c

   1 /*
   2  * A driver for the Integrated Circuits ICS932S401
   3  * Copyright (C) 2008 IBM
   4  *
   5  * Author: Darrick J. Wong <djwong@us.ibm.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/jiffies.h>
  24 #include <linux/i2c.h>
  25 #include <linux/err.h>
  26 #include <linux/mutex.h>
  27 #include <linux/delay.h>
  28 #include <linux/log2.h>
  29 #include <linux/slab.h>
  30
  31 /* Addresses to scan */
  32 static const unsigned short normal_i2c[] = { 0x69, I2C_CLIENT_END };
  33
  34 /* ICS932S401 registers */
  35 #define ICS932S401_REG_CFG2                     0x01
  36 #define         ICS932S401_CFG1_SPREAD          0x01
  37 #define ICS932S401_REG_CFG7                     0x06
  38 #define         ICS932S401_FS_MASK              0x07
  39 #define ICS932S401_REG_VENDOR_REV               0x07
  40 #define         ICS932S401_VENDOR               1
  41 #define         ICS932S401_VENDOR_MASK          0x0F
  42 #define         ICS932S401_REV                  4
  43 #define         ICS932S401_REV_SHIFT            4
  44 #define ICS932S401_REG_DEVICE                   0x09
  45 #define         ICS932S401_DEVICE               11
  46 #define ICS932S401_REG_CTRL                     0x0A
  47 #define         ICS932S401_MN_ENABLED           0x80
  48 #define         ICS932S401_CPU_ALT              0x04
  49 #define         ICS932S401_SRC_ALT              0x08
  50 #define ICS932S401_REG_CPU_M_CTRL               0x0B
  51 #define         ICS932S401_M_MASK               0x3F
  52 #define ICS932S401_REG_CPU_N_CTRL               0x0C
  53 #define ICS932S401_REG_CPU_SPREAD1              0x0D
  54 #define ICS932S401_REG_CPU_SPREAD2              0x0E
  55 #define         ICS932S401_SPREAD_MASK          0x7FFF
  56 #define ICS932S401_REG_SRC_M_CTRL               0x0F
  57 #define ICS932S401_REG_SRC_N_CTRL               0x10
  58 #define ICS932S401_REG_SRC_SPREAD1              0x11
  59 #define ICS932S401_REG_SRC_SPREAD2              0x12
  60 #define ICS932S401_REG_CPU_DIVISOR              0x13
  61 #define         ICS932S401_CPU_DIVISOR_SHIFT    4
  62 #define ICS932S401_REG_PCISRC_DIVISOR           0x14
  63 #define         ICS932S401_SRC_DIVISOR_MASK     0x0F
  64 #define         ICS932S401_PCI_DIVISOR_SHIFT    4
  65
  66 /* Base clock is 14.318MHz */
  67 #define BASE_CLOCK                              14318
  68
  69 #define NUM_REGS                                21
  70 #define NUM_MIRRORED_REGS                       15
  71
  72 static int regs_to_copy[NUM_MIRRORED_REGS] = {
  73         ICS932S401_REG_CFG2,
  74         ICS932S401_REG_CFG7,
  75         ICS932S401_REG_VENDOR_REV,
  76         ICS932S401_REG_DEVICE,
  77         ICS932S401_REG_CTRL,
  78         ICS932S401_REG_CPU_M_CTRL,
  79         ICS932S401_REG_CPU_N_CTRL,
  80         ICS932S401_REG_CPU_SPREAD1,
  81         ICS932S401_REG_CPU_SPREAD2,
  82         ICS932S401_REG_SRC_M_CTRL,
  83         ICS932S401_REG_SRC_N_CTRL,
  84         ICS932S401_REG_SRC_SPREAD1,
  85         ICS932S401_REG_SRC_SPREAD2,
  86         ICS932S401_REG_CPU_DIVISOR,
  87         ICS932S401_REG_PCISRC_DIVISOR,
  88 };
  89
  90 /* How often do we reread sensors values? (In jiffies) */
  91 #define SENSOR_REFRESH_INTERVAL (2 * HZ)
  92
  93 /* How often do we reread sensor limit values? (In jiffies) */
  94 #define LIMIT_REFRESH_INTERVAL  (60 * HZ)
  95
  96 struct ics932s401_data {
  97         struct attribute_group  attrs;
  98         struct mutex            lock;
  99         char                    sensors_valid;
 100         unsigned long           sensors_last_updated;   /* In jiffies */
 101
 102         u8                      regs[NUM_REGS];
 103 };
 104
 105 static int ics932s401_probe(struct i2c_client *client,
 106                          const struct i2c_device_id *id);
 107 static int ics932s401_detect(struct i2c_client *client,
 108                           struct i2c_board_info *info);
 109 static int ics932s401_remove(struct i2c_client *client);
 110
 111 static const struct i2c_device_id ics932s401_id[] = {
 112         { "ics932s401", 0 },
 113         { }
 114 };
 115 MODULE_DEVICE_TABLE(i2c, ics932s401_id);
 116
 117 static struct i2c_driver ics932s401_driver = {
 118         .class          = I2C_CLASS_HWMON,
 119         .driver = {
 120                 .name   = "ics932s401",
 121         },
 122         .probe          = ics932s401_probe,
 123         .remove         = ics932s401_remove,
 124         .id_table       = ics932s401_id,
 125         .detect         = ics932s401_detect,
 126         .address_list   = normal_i2c,
 127 };
 128
 129 static struct ics932s401_data *ics932s401_update_device(struct device *dev)
 130 {
 131         struct i2c_client *client = to_i2c_client(dev);
 132         struct ics932s401_data *data = i2c_get_clientdata(client);
 133         unsigned long local_jiffies = jiffies;
 134         int i, temp;
 135
 136         mutex_lock(&data->lock);
 137         if (time_before(local_jiffies, data->sensors_last_updated +
 138                 SENSOR_REFRESH_INTERVAL)
 139                 && data->sensors_valid)
 140                 goto out;
 141
 142         /*
 143          * Each register must be read as a word and then right shifted 8 bits.
 144          * Not really sure why this is; setting the "byte count programming"
 145          * register to 1 does not fix this problem.
 146          */
 147         for (i = 0; i < NUM_MIRRORED_REGS; i++) {
 148                 temp = i2c_smbus_read_word_data(client, regs_to_copy[i]);
 149                 data->regs[regs_to_copy[i]] = temp >> 8;
 150         }
 151
 152         data->sensors_last_updated = local_jiffies;
 153         data->sensors_valid = 1;
 154
 155 out:
 156         mutex_unlock(&data->lock);
 157         return data;
 158 }
 159
 160 static ssize_t show_spread_enabled(struct device *dev,
 161                                    struct device_attribute *devattr,
 162                                    char *buf)
 163 {
 164         struct ics932s401_data *data = ics932s401_update_device(dev);
 165
 166         if (data->regs[ICS932S401_REG_CFG2] & ICS932S401_CFG1_SPREAD)
 167                 return sprintf(buf, "1\n");
 168
 169         return sprintf(buf, "0\n");
 170 }
 171
 172 /* bit to cpu khz map */
 173 static const int fs_speeds[] = {
 174         266666,
 175         133333,
 176         200000,
 177         166666,
 178         333333,
 179         100000,
 180         400000,
 181         0,
 182 };
 183
 184 /* clock divisor map */
 185 static const int divisors[] = {2, 3, 5, 15, 4, 6, 10, 30, 8, 12, 20, 60, 16,
 186                                24, 40, 120};
 187
 188 /* Calculate CPU frequency from the M/N registers. */
 189 static int calculate_cpu_freq(struct ics932s401_data *data)
 190 {
 191         int m, n, freq;
 192
 193         m = data->regs[ICS932S401_REG_CPU_M_CTRL] & ICS932S401_M_MASK;
 194         n = data->regs[ICS932S401_REG_CPU_N_CTRL];
 195
 196         /* Pull in bits 8 & 9 from the M register */
 197         n |= ((int)data->regs[ICS932S401_REG_CPU_M_CTRL] & 0x80) << 1;
 198         n |= ((int)data->regs[ICS932S401_REG_CPU_M_CTRL] & 0x40) << 3;
 199
 200         freq = BASE_CLOCK * (n + 8) / (m + 2);
 201         freq /= divisors[data->regs[ICS932S401_REG_CPU_DIVISOR] >>
 202                          ICS932S401_CPU_DIVISOR_SHIFT];
 203
 204         return freq;
 205 }
 206
 207 static ssize_t show_cpu_clock(struct device *dev,
 208                               struct device_attribute *devattr,
 209                               char *buf)
 210 {
 211         struct ics932s401_data *data = ics932s401_update_device(dev);
 212
 213         return sprintf(buf, "%d\n", calculate_cpu_freq(data));
 214 }
 215
 216 static ssize_t show_cpu_clock_sel(struct device *dev,
 217                                   struct device_attribute *devattr,
 218                                   char *buf)
 219 {
 220         struct ics932s401_data *data = ics932s401_update_device(dev);
 221         int freq;
 222
 223         if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
 224                 freq = calculate_cpu_freq(data);
 225         else {
 226                 /* Freq is neatly wrapped up for us */
 227                 int fid = data->regs[ICS932S401_REG_CFG7] & ICS932S401_FS_MASK;
 228                 freq = fs_speeds[fid];
 229                 if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_CPU_ALT) {
 230                         switch (freq) {
 231                         case 166666:
 232                                 freq = 160000;
 233                                 break;
 234                         case 333333:
 235                                 freq = 320000;
 236                                 break;
 237                         }
 238                 }
 239         }
 240
 241         return sprintf(buf, "%d\n", freq);
 242 }
 243
 244 /* Calculate SRC frequency from the M/N registers. */
 245 static int calculate_src_freq(struct ics932s401_data *data)
 246 {
 247         int m, n, freq;
 248
 249         m = data->regs[ICS932S401_REG_SRC_M_CTRL] & ICS932S401_M_MASK;
 250         n = data->regs[ICS932S401_REG_SRC_N_CTRL];
 251
 252         /* Pull in bits 8 & 9 from the M register */
 253         n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x80) << 1;
 254         n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x40) << 3;
 255
 256         freq = BASE_CLOCK * (n + 8) / (m + 2);
 257         freq /= divisors[data->regs[ICS932S401_REG_PCISRC_DIVISOR] &
 258                          ICS932S401_SRC_DIVISOR_MASK];
 259
 260         return freq;
 261 }
 262
 263 static ssize_t show_src_clock(struct device *dev,
 264                               struct device_attribute *devattr,
 265                               char *buf)
 266 {
 267         struct ics932s401_data *data = ics932s401_update_device(dev);
 268
 269         return sprintf(buf, "%d\n", calculate_src_freq(data));
 270 }
 271
 272 static ssize_t show_src_clock_sel(struct device *dev,
 273                                   struct device_attribute *devattr,
 274                                   char *buf)
 275 {
 276         struct ics932s401_data *data = ics932s401_update_device(dev);
 277         int freq;
 278
 279         if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
 280                 freq = calculate_src_freq(data);
 281         else
 282                 /* Freq is neatly wrapped up for us */
 283                 if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_CPU_ALT &&
 284                     data->regs[ICS932S401_REG_CTRL] & ICS932S401_SRC_ALT)
 285                         freq = 96000;
 286                 else
 287                         freq = 100000;
 288
 289         return sprintf(buf, "%d\n", freq);
 290 }
 291
 292 /* Calculate PCI frequency from the SRC M/N registers. */
 293 static int calculate_pci_freq(struct ics932s401_data *data)
 294 {
 295         int m, n, freq;
 296
 297         m = data->regs[ICS932S401_REG_SRC_M_CTRL] & ICS932S401_M_MASK;
 298         n = data->regs[ICS932S401_REG_SRC_N_CTRL];
 299
 300         /* Pull in bits 8 & 9 from the M register */
 301         n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x80) << 1;
 302         n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x40) << 3;
 303
 304         freq = BASE_CLOCK * (n + 8) / (m + 2);
 305         freq /= divisors[data->regs[ICS932S401_REG_PCISRC_DIVISOR] >>
 306                          ICS932S401_PCI_DIVISOR_SHIFT];
 307
 308         return freq;
 309 }
 310
 311 static ssize_t show_pci_clock(struct device *dev,
 312                               struct device_attribute *devattr,
 313                               char *buf)
 314 {
 315         struct ics932s401_data *data = ics932s401_update_device(dev);
 316
 317         return sprintf(buf, "%d\n", calculate_pci_freq(data));
 318 }
 319
 320 static ssize_t show_pci_clock_sel(struct device *dev,
 321                                   struct device_attribute *devattr,
 322                                   char *buf)
 323 {
 324         struct ics932s401_data *data = ics932s401_update_device(dev);
 325         int freq;
 326
 327         if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
 328                 freq = calculate_pci_freq(data);
 329         else
 330                 freq = 33333;
 331
 332         return sprintf(buf, "%d\n", freq);
 333 }
 334
 335 static ssize_t show_value(struct device *dev,
 336                           struct device_attribute *devattr,
 337                           char *buf);
 338
 339 static ssize_t show_spread(struct device *dev,
 340                            struct device_attribute *devattr,
 341                            char *buf);
 342
 343 static DEVICE_ATTR(spread_enabled, S_IRUGO, show_spread_enabled, NULL);
 344 static DEVICE_ATTR(cpu_clock_selection, S_IRUGO, show_cpu_clock_sel, NULL);
 345 static DEVICE_ATTR(cpu_clock, S_IRUGO, show_cpu_clock, NULL);
 346 static DEVICE_ATTR(src_clock_selection, S_IRUGO, show_src_clock_sel, NULL);
 347 static DEVICE_ATTR(src_clock, S_IRUGO, show_src_clock, NULL);
 348 static DEVICE_ATTR(pci_clock_selection, S_IRUGO, show_pci_clock_sel, NULL);
 349 static DEVICE_ATTR(pci_clock, S_IRUGO, show_pci_clock, NULL);
 350 static DEVICE_ATTR(usb_clock, S_IRUGO, show_value, NULL);
 351 static DEVICE_ATTR(ref_clock, S_IRUGO, show_value, NULL);
 352 static DEVICE_ATTR(cpu_spread, S_IRUGO, show_spread, NULL);
 353 static DEVICE_ATTR(src_spread, S_IRUGO, show_spread, NULL);
 354
 355 static struct attribute *ics932s401_attr[] =
 356 {
 357         &dev_attr_spread_enabled.attr,
 358         &dev_attr_cpu_clock_selection.attr,
 359         &dev_attr_cpu_clock.attr,
 360         &dev_attr_src_clock_selection.attr,
 361         &dev_attr_src_clock.attr,
 362         &dev_attr_pci_clock_selection.attr,
 363         &dev_attr_pci_clock.attr,
 364         &dev_attr_usb_clock.attr,
 365         &dev_attr_ref_clock.attr,
 366         &dev_attr_cpu_spread.attr,
 367         &dev_attr_src_spread.attr,
 368         NULL
 369 };
 370
 371 static ssize_t show_value(struct device *dev,
 372                           struct device_attribute *devattr,
 373                           char *buf)
 374 {
 375         int x;
 376
 377         if (devattr == &dev_attr_usb_clock)
 378                 x = 48000;
 379         else if (devattr == &dev_attr_ref_clock)
 380                 x = BASE_CLOCK;
 381         else
 382                 BUG();
 383
 384         return sprintf(buf, "%d\n", x);
 385 }
 386
 387 static ssize_t show_spread(struct device *dev,
 388                            struct device_attribute *devattr,
 389                            char *buf)
 390 {
 391         struct ics932s401_data *data = ics932s401_update_device(dev);
 392         int reg;
 393         unsigned long val;
 394
 395         if (!(data->regs[ICS932S401_REG_CFG2] & ICS932S401_CFG1_SPREAD))
 396                 return sprintf(buf, "0%%\n");
 397
 398         if (devattr == &dev_attr_src_spread)
 399                 reg = ICS932S401_REG_SRC_SPREAD1;
 400         else if (devattr == &dev_attr_cpu_spread)
 401                 reg = ICS932S401_REG_CPU_SPREAD1;
 402         else
 403                 BUG();
 404
 405         val = data->regs[reg] | (data->regs[reg + 1] << 8);
 406         val &= ICS932S401_SPREAD_MASK;
 407
 408         /* Scale 0..2^14 to -0.5. */
 409         val = 500000 * val / 16384;
 410         return sprintf(buf, "-0.%lu%%\n", val);
 411 }
 412
 413 /* Return 0 if detection is successful, -ENODEV otherwise */
 414 static int ics932s401_detect(struct i2c_client *client,
 415                           struct i2c_board_info *info)
 416 {
 417         struct i2c_adapter *adapter = client->adapter;
 418         int vendor, device, revision;
 419
 420         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 421                 return -ENODEV;
 422
 423         vendor = i2c_smbus_read_word_data(client, ICS932S401_REG_VENDOR_REV);
 424         vendor >>= 8;
 425         revision = vendor >> ICS932S401_REV_SHIFT;
 426         vendor &= ICS932S401_VENDOR_MASK;
 427         if (vendor != ICS932S401_VENDOR)
 428                 return -ENODEV;
 429
 430         device = i2c_smbus_read_word_data(client, ICS932S401_REG_DEVICE);
 431         device >>= 8;
 432         if (device != ICS932S401_DEVICE)
 433                 return -ENODEV;
 434
 435         if (revision != ICS932S401_REV)
 436                 dev_info(&adapter->dev, "Unknown revision %d\n", revision);
 437
 438         strlcpy(info->type, "ics932s401", I2C_NAME_SIZE);
 439
 440         return 0;
 441 }
 442
 443 static int ics932s401_probe(struct i2c_client *client,
 444                          const struct i2c_device_id *id)
 445 {
 446         struct ics932s401_data *data;
 447         int err;
 448
 449         data = kzalloc(sizeof(struct ics932s401_data), GFP_KERNEL);
 450         if (!data) {
 451                 err = -ENOMEM;
 452                 goto exit;
 453         }
 454
 455         i2c_set_clientdata(client, data);
 456         mutex_init(&data->lock);
 457
 458         dev_info(&client->dev, "%s chip found\n", client->name);
 459
 460         /* Register sysfs hooks */
 461         data->attrs.attrs = ics932s401_attr;
 462         err = sysfs_create_group(&client->dev.kobj, &data->attrs);
 463         if (err)
 464                 goto exit_free;
 465
 466         return 0;
 467
 468 exit_free:
 469         kfree(data);
 470 exit:
 471         return err;
 472 }
 473
 474 static int ics932s401_remove(struct i2c_client *client)
 475 {
 476         struct ics932s401_data *data = i2c_get_clientdata(client);
 477
 478         sysfs_remove_group(&client->dev.kobj, &data->attrs);
 479         kfree(data);
 480         return 0;
 481 }
 482
 483 module_i2c_driver(ics932s401_driver);
 484
 485 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
 486 MODULE_DESCRIPTION("ICS932S401 driver");
 487 MODULE_LICENSE("GPL");
 488
 489 /* IBM IntelliStation Z30 */
 490 MODULE_ALIAS("dmi:bvnIBM:*:rn9228:*");
 491 MODULE_ALIAS("dmi:bvnIBM:*:rn9232:*");
 492
 493 /* IBM x3650/x3550 */
 494 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650*");
 495 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550*");