drivers/hwmon/ntc_thermistor.c

   1 /*
   2  * ntc_thermistor.c - NTC Thermistors
   3  *
   4  *  Copyright (C) 2010 Samsung Electronics
   5  *  MyungJoo Ham <myungjoo.ham@samsung.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
  23 #include <linux/slab.h>
  24 #include <linux/module.h>
  25 #include <linux/pm_runtime.h>
  26 #include <linux/math64.h>
  27 #include <linux/platform_device.h>
  28 #include <linux/err.h>
  29 #include <linux/of.h>
  30 #include <linux/of_device.h>
  31
  32 #include <linux/platform_data/ntc_thermistor.h>
  33
  34 #include <linux/iio/iio.h>
  35 #include <linux/iio/machine.h>
  36 #include <linux/iio/driver.h>
  37 #include <linux/iio/consumer.h>
  38
  39 #include <linux/hwmon.h>
  40 #include <linux/hwmon-sysfs.h>
  41 #include <linux/thermal.h>
  42
  43 struct ntc_compensation {
  44         int             temp_c;
  45         unsigned int    ohm;
  46 };
  47
  48 /* Order matters, ntc_match references the entries by index */
  49 static const struct platform_device_id ntc_thermistor_id[] = {
  50         { "ncp15wb473", TYPE_NCPXXWB473 },
  51         { "ncp18wb473", TYPE_NCPXXWB473 },
  52         { "ncp21wb473", TYPE_NCPXXWB473 },
  53         { "ncp03wb473", TYPE_NCPXXWB473 },
  54         { "ncp15wl333", TYPE_NCPXXWL333 },
  55         { "b57330v2103", TYPE_B57330V2103},
  56         { "ncp03wf104", TYPE_NCPXXWF104 },
  57         { "ncp15xh103", TYPE_NCPXXXH103 },
  58         { },
  59 };
  60
  61 /*
  62  * A compensation table should be sorted by the values of .ohm
  63  * in descending order.
  64  * The following compensation tables are from the specification of Murata NTC
  65  * Thermistors Datasheet
  66  */
  67 static const struct ntc_compensation ncpXXwb473[] = {
  68         { .temp_c       = -40, .ohm     = 1747920 },
  69         { .temp_c       = -35, .ohm     = 1245428 },
  70         { .temp_c       = -30, .ohm     = 898485 },
  71         { .temp_c       = -25, .ohm     = 655802 },
  72         { .temp_c       = -20, .ohm     = 483954 },
  73         { .temp_c       = -15, .ohm     = 360850 },
  74         { .temp_c       = -10, .ohm     = 271697 },
  75         { .temp_c       = -5, .ohm      = 206463 },
  76         { .temp_c       = 0, .ohm       = 158214 },
  77         { .temp_c       = 5, .ohm       = 122259 },
  78         { .temp_c       = 10, .ohm      = 95227 },
  79         { .temp_c       = 15, .ohm      = 74730 },
  80         { .temp_c       = 20, .ohm      = 59065 },
  81         { .temp_c       = 25, .ohm      = 47000 },
  82         { .temp_c       = 30, .ohm      = 37643 },
  83         { .temp_c       = 35, .ohm      = 30334 },
  84         { .temp_c       = 40, .ohm      = 24591 },
  85         { .temp_c       = 45, .ohm      = 20048 },
  86         { .temp_c       = 50, .ohm      = 16433 },
  87         { .temp_c       = 55, .ohm      = 13539 },
  88         { .temp_c       = 60, .ohm      = 11209 },
  89         { .temp_c       = 65, .ohm      = 9328 },
  90         { .temp_c       = 70, .ohm      = 7798 },
  91         { .temp_c       = 75, .ohm      = 6544 },
  92         { .temp_c       = 80, .ohm      = 5518 },
  93         { .temp_c       = 85, .ohm      = 4674 },
  94         { .temp_c       = 90, .ohm      = 3972 },
  95         { .temp_c       = 95, .ohm      = 3388 },
  96         { .temp_c       = 100, .ohm     = 2902 },
  97         { .temp_c       = 105, .ohm     = 2494 },
  98         { .temp_c       = 110, .ohm     = 2150 },
  99         { .temp_c       = 115, .ohm     = 1860 },
 100         { .temp_c       = 120, .ohm     = 1615 },
 101         { .temp_c       = 125, .ohm     = 1406 },
 102 };
 103 static const struct ntc_compensation ncpXXwl333[] = {
 104         { .temp_c       = -40, .ohm     = 1610154 },
 105         { .temp_c       = -35, .ohm     = 1130850 },
 106         { .temp_c       = -30, .ohm     = 802609 },
 107         { .temp_c       = -25, .ohm     = 575385 },
 108         { .temp_c       = -20, .ohm     = 416464 },
 109         { .temp_c       = -15, .ohm     = 304219 },
 110         { .temp_c       = -10, .ohm     = 224193 },
 111         { .temp_c       = -5, .ohm      = 166623 },
 112         { .temp_c       = 0, .ohm       = 124850 },
 113         { .temp_c       = 5, .ohm       = 94287 },
 114         { .temp_c       = 10, .ohm      = 71747 },
 115         { .temp_c       = 15, .ohm      = 54996 },
 116         { .temp_c       = 20, .ohm      = 42455 },
 117         { .temp_c       = 25, .ohm      = 33000 },
 118         { .temp_c       = 30, .ohm      = 25822 },
 119         { .temp_c       = 35, .ohm      = 20335 },
 120         { .temp_c       = 40, .ohm      = 16115 },
 121         { .temp_c       = 45, .ohm      = 12849 },
 122         { .temp_c       = 50, .ohm      = 10306 },
 123         { .temp_c       = 55, .ohm      = 8314 },
 124         { .temp_c       = 60, .ohm      = 6746 },
 125         { .temp_c       = 65, .ohm      = 5503 },
 126         { .temp_c       = 70, .ohm      = 4513 },
 127         { .temp_c       = 75, .ohm      = 3721 },
 128         { .temp_c       = 80, .ohm      = 3084 },
 129         { .temp_c       = 85, .ohm      = 2569 },
 130         { .temp_c       = 90, .ohm      = 2151 },
 131         { .temp_c       = 95, .ohm      = 1809 },
 132         { .temp_c       = 100, .ohm     = 1529 },
 133         { .temp_c       = 105, .ohm     = 1299 },
 134         { .temp_c       = 110, .ohm     = 1108 },
 135         { .temp_c       = 115, .ohm     = 949 },
 136         { .temp_c       = 120, .ohm     = 817 },
 137         { .temp_c       = 125, .ohm     = 707 },
 138 };
 139
 140 static const struct ntc_compensation ncpXXwf104[] = {
 141         { .temp_c       = -40, .ohm     = 4397119 },
 142         { .temp_c       = -35, .ohm     = 3088599 },
 143         { .temp_c       = -30, .ohm     = 2197225 },
 144         { .temp_c       = -25, .ohm     = 1581881 },
 145         { .temp_c       = -20, .ohm     = 1151037 },
 146         { .temp_c       = -15, .ohm     = 846579 },
 147         { .temp_c       = -10, .ohm     = 628988 },
 148         { .temp_c       = -5, .ohm      = 471632 },
 149         { .temp_c       = 0, .ohm       = 357012 },
 150         { .temp_c       = 5, .ohm       = 272500 },
 151         { .temp_c       = 10, .ohm      = 209710 },
 152         { .temp_c       = 15, .ohm      = 162651 },
 153         { .temp_c       = 20, .ohm      = 127080 },
 154         { .temp_c       = 25, .ohm      = 100000 },
 155         { .temp_c       = 30, .ohm      = 79222 },
 156         { .temp_c       = 35, .ohm      = 63167 },
 157         { .temp_c       = 40, .ohm      = 50677 },
 158         { .temp_c       = 45, .ohm      = 40904 },
 159         { .temp_c       = 50, .ohm      = 33195 },
 160         { .temp_c       = 55, .ohm      = 27091 },
 161         { .temp_c       = 60, .ohm      = 22224 },
 162         { .temp_c       = 65, .ohm      = 18323 },
 163         { .temp_c       = 70, .ohm      = 15184 },
 164         { .temp_c       = 75, .ohm      = 12635 },
 165         { .temp_c       = 80, .ohm      = 10566 },
 166         { .temp_c       = 85, .ohm      = 8873 },
 167         { .temp_c       = 90, .ohm      = 7481 },
 168         { .temp_c       = 95, .ohm      = 6337 },
 169         { .temp_c       = 100, .ohm     = 5384 },
 170         { .temp_c       = 105, .ohm     = 4594 },
 171         { .temp_c       = 110, .ohm     = 3934 },
 172         { .temp_c       = 115, .ohm     = 3380 },
 173         { .temp_c       = 120, .ohm     = 2916 },
 174         { .temp_c       = 125, .ohm     = 2522 },
 175 };
 176
 177 static const struct ntc_compensation ncpXXxh103[] = {
 178         { .temp_c       = -40, .ohm     = 247565 },
 179         { .temp_c       = -35, .ohm     = 181742 },
 180         { .temp_c       = -30, .ohm     = 135128 },
 181         { .temp_c       = -25, .ohm     = 101678 },
 182         { .temp_c       = -20, .ohm     = 77373 },
 183         { .temp_c       = -15, .ohm     = 59504 },
 184         { .temp_c       = -10, .ohm     = 46222 },
 185         { .temp_c       = -5, .ohm      = 36244 },
 186         { .temp_c       = 0, .ohm       = 28674 },
 187         { .temp_c       = 5, .ohm       = 22878 },
 188         { .temp_c       = 10, .ohm      = 18399 },
 189         { .temp_c       = 15, .ohm      = 14910 },
 190         { .temp_c       = 20, .ohm      = 12169 },
 191         { .temp_c       = 25, .ohm      = 10000 },
 192         { .temp_c       = 30, .ohm      = 8271 },
 193         { .temp_c       = 35, .ohm      = 6883 },
 194         { .temp_c       = 40, .ohm      = 5762 },
 195         { .temp_c       = 45, .ohm      = 4851 },
 196         { .temp_c       = 50, .ohm      = 4105 },
 197         { .temp_c       = 55, .ohm      = 3492 },
 198         { .temp_c       = 60, .ohm      = 2985 },
 199         { .temp_c       = 65, .ohm      = 2563 },
 200         { .temp_c       = 70, .ohm      = 2211 },
 201         { .temp_c       = 75, .ohm      = 1915 },
 202         { .temp_c       = 80, .ohm      = 1666 },
 203         { .temp_c       = 85, .ohm      = 1454 },
 204         { .temp_c       = 90, .ohm      = 1275 },
 205         { .temp_c       = 95, .ohm      = 1121 },
 206         { .temp_c       = 100, .ohm     = 990 },
 207         { .temp_c       = 105, .ohm     = 876 },
 208         { .temp_c       = 110, .ohm     = 779 },
 209         { .temp_c       = 115, .ohm     = 694 },
 210         { .temp_c       = 120, .ohm     = 620 },
 211         { .temp_c       = 125, .ohm     = 556 },
 212 };
 213
 214 /*
 215  * The following compensation table is from the specification of EPCOS NTC
 216  * Thermistors Datasheet
 217  */
 218 static const struct ntc_compensation b57330v2103[] = {
 219         { .temp_c       = -40, .ohm     = 190030 },
 220         { .temp_c       = -35, .ohm     = 145360 },
 221         { .temp_c       = -30, .ohm     = 112060 },
 222         { .temp_c       = -25, .ohm     = 87041 },
 223         { .temp_c       = -20, .ohm     = 68104 },
 224         { .temp_c       = -15, .ohm     = 53665 },
 225         { .temp_c       = -10, .ohm     = 42576 },
 226         { .temp_c       = -5, .ohm      = 34001 },
 227         { .temp_c       = 0, .ohm       = 27326 },
 228         { .temp_c       = 5, .ohm       = 22096 },
 229         { .temp_c       = 10, .ohm      = 17973 },
 230         { .temp_c       = 15, .ohm      = 14703 },
 231         { .temp_c       = 20, .ohm      = 12090 },
 232         { .temp_c       = 25, .ohm      = 10000 },
 233         { .temp_c       = 30, .ohm      = 8311 },
 234         { .temp_c       = 35, .ohm      = 6941 },
 235         { .temp_c       = 40, .ohm      = 5825 },
 236         { .temp_c       = 45, .ohm      = 4911 },
 237         { .temp_c       = 50, .ohm      = 4158 },
 238         { .temp_c       = 55, .ohm      = 3536 },
 239         { .temp_c       = 60, .ohm      = 3019 },
 240         { .temp_c       = 65, .ohm      = 2588 },
 241         { .temp_c       = 70, .ohm      = 2227 },
 242         { .temp_c       = 75, .ohm      = 1924 },
 243         { .temp_c       = 80, .ohm      = 1668 },
 244         { .temp_c       = 85, .ohm      = 1451 },
 245         { .temp_c       = 90, .ohm      = 1266 },
 246         { .temp_c       = 95, .ohm      = 1108 },
 247         { .temp_c       = 100, .ohm     = 973 },
 248         { .temp_c       = 105, .ohm     = 857 },
 249         { .temp_c       = 110, .ohm     = 757 },
 250         { .temp_c       = 115, .ohm     = 671 },
 251         { .temp_c       = 120, .ohm     = 596 },
 252         { .temp_c       = 125, .ohm     = 531 },
 253 };
 254
 255 struct ntc_data {
 256         struct ntc_thermistor_platform_data *pdata;
 257         const struct ntc_compensation *comp;
 258         int n_comp;
 259 };
 260
 261 #if defined(CONFIG_OF) && IS_ENABLED(CONFIG_IIO)
 262 static int ntc_adc_iio_read(struct ntc_thermistor_platform_data *pdata)
 263 {
 264         struct iio_channel *channel = pdata->chan;
 265         int raw, uv, ret;
 266
 267         ret = iio_read_channel_raw(channel, &raw);
 268         if (ret < 0) {
 269                 pr_err("read channel() error: %d\n", ret);
 270                 return ret;
 271         }
 272
 273         ret = iio_convert_raw_to_processed(channel, raw, &uv, 1000);
 274         if (ret < 0) {
 275                 /* Assume 12 bit ADC with vref at pullup_uv */
 276                 uv = (pdata->pullup_uv * (s64)raw) >> 12;
 277         }
 278
 279         return uv;
 280 }
 281
 282 static const struct of_device_id ntc_match[] = {
 283         { .compatible = "murata,ncp15wb473",
 284                 .data = &ntc_thermistor_id[0] },
 285         { .compatible = "murata,ncp18wb473",
 286                 .data = &ntc_thermistor_id[1] },
 287         { .compatible = "murata,ncp21wb473",
 288                 .data = &ntc_thermistor_id[2] },
 289         { .compatible = "murata,ncp03wb473",
 290                 .data = &ntc_thermistor_id[3] },
 291         { .compatible = "murata,ncp15wl333",
 292                 .data = &ntc_thermistor_id[4] },
 293         { .compatible = "epcos,b57330v2103",
 294                 .data = &ntc_thermistor_id[5]},
 295         { .compatible = "murata,ncp03wf104",
 296                 .data = &ntc_thermistor_id[6] },
 297         { .compatible = "murata,ncp15xh103",
 298                 .data = &ntc_thermistor_id[7] },
 299
 300         /* Usage of vendor name "ntc" is deprecated */
 301         { .compatible = "ntc,ncp15wb473",
 302                 .data = &ntc_thermistor_id[0] },
 303         { .compatible = "ntc,ncp18wb473",
 304                 .data = &ntc_thermistor_id[1] },
 305         { .compatible = "ntc,ncp21wb473",
 306                 .data = &ntc_thermistor_id[2] },
 307         { .compatible = "ntc,ncp03wb473",
 308                 .data = &ntc_thermistor_id[3] },
 309         { .compatible = "ntc,ncp15wl333",
 310                 .data = &ntc_thermistor_id[4] },
 311         { },
 312 };
 313 MODULE_DEVICE_TABLE(of, ntc_match);
 314
 315 static struct ntc_thermistor_platform_data *
 316 ntc_thermistor_parse_dt(struct device *dev)
 317 {
 318         struct iio_channel *chan;
 319         enum iio_chan_type type;
 320         struct device_node *np = dev->of_node;
 321         struct ntc_thermistor_platform_data *pdata;
 322         int ret;
 323
 324         if (!np)
 325                 return NULL;
 326
 327         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 328         if (!pdata)
 329                 return ERR_PTR(-ENOMEM);
 330
 331         chan = devm_iio_channel_get(dev, NULL);
 332         if (IS_ERR(chan))
 333                 return ERR_CAST(chan);
 334
 335         ret = iio_get_channel_type(chan, &type);
 336         if (ret < 0)
 337                 return ERR_PTR(ret);
 338
 339         if (type != IIO_VOLTAGE)
 340                 return ERR_PTR(-EINVAL);
 341
 342         if (of_property_read_u32(np, "pullup-uv", &pdata->pullup_uv))
 343                 return ERR_PTR(-ENODEV);
 344         if (of_property_read_u32(np, "pullup-ohm", &pdata->pullup_ohm))
 345                 return ERR_PTR(-ENODEV);
 346         if (of_property_read_u32(np, "pulldown-ohm", &pdata->pulldown_ohm))
 347                 return ERR_PTR(-ENODEV);
 348
 349         if (of_find_property(np, "connected-positive", NULL))
 350                 pdata->connect = NTC_CONNECTED_POSITIVE;
 351         else /* status change should be possible if not always on. */
 352                 pdata->connect = NTC_CONNECTED_GROUND;
 353
 354         pdata->chan = chan;
 355         pdata->read_uv = ntc_adc_iio_read;
 356
 357         return pdata;
 358 }
 359 #else
 360 static struct ntc_thermistor_platform_data *
 361 ntc_thermistor_parse_dt(struct device *dev)
 362 {
 363         return NULL;
 364 }
 365
 366 #define ntc_match       NULL
 367
 368 #endif
 369
 370 static inline u64 div64_u64_safe(u64 dividend, u64 divisor)
 371 {
 372         if (divisor == 0 && dividend == 0)
 373                 return 0;
 374         if (divisor == 0)
 375                 return UINT_MAX;
 376         return div64_u64(dividend, divisor);
 377 }
 378
 379 static int get_ohm_of_thermistor(struct ntc_data *data, unsigned int uv)
 380 {
 381         struct ntc_thermistor_platform_data *pdata = data->pdata;
 382         u32 puv = pdata->pullup_uv;
 383         u64 n, puo, pdo;
 384         puo = pdata->pullup_ohm;
 385         pdo = pdata->pulldown_ohm;
 386
 387         if (uv == 0)
 388                 return (pdata->connect == NTC_CONNECTED_POSITIVE) ?
 389                         INT_MAX : 0;
 390         if (uv >= puv)
 391                 return (pdata->connect == NTC_CONNECTED_POSITIVE) ?
 392                         0 : INT_MAX;
 393
 394         if (pdata->connect == NTC_CONNECTED_POSITIVE && puo == 0)
 395                 n = div_u64(pdo * (puv - uv), uv);
 396         else if (pdata->connect == NTC_CONNECTED_GROUND && pdo == 0)
 397                 n = div_u64(puo * uv, puv - uv);
 398         else if (pdata->connect == NTC_CONNECTED_POSITIVE)
 399                 n = div64_u64_safe(pdo * puo * (puv - uv),
 400                                 puo * uv - pdo * (puv - uv));
 401         else
 402                 n = div64_u64_safe(pdo * puo * uv, pdo * (puv - uv) - puo * uv);
 403
 404         if (n > INT_MAX)
 405                 n = INT_MAX;
 406         return n;
 407 }
 408
 409 static void lookup_comp(struct ntc_data *data, unsigned int ohm,
 410                         int *i_low, int *i_high)
 411 {
 412         int start, end, mid;
 413
 414         /*
 415          * Handle special cases: Resistance is higher than or equal to
 416          * resistance in first table entry, or resistance is lower or equal
 417          * to resistance in last table entry.
 418          * In these cases, return i_low == i_high, either pointing to the
 419          * beginning or to the end of the table depending on the condition.
 420          */
 421         if (ohm >= data->comp[0].ohm) {
 422                 *i_low = 0;
 423                 *i_high = 0;
 424                 return;
 425         }
 426         if (ohm <= data->comp[data->n_comp - 1].ohm) {
 427                 *i_low = data->n_comp - 1;
 428                 *i_high = data->n_comp - 1;
 429                 return;
 430         }
 431
 432         /* Do a binary search on compensation table */
 433         start = 0;
 434         end = data->n_comp;
 435         while (start < end) {
 436                 mid = start + (end - start) / 2;
 437                 /*
 438                  * start <= mid < end
 439                  * data->comp[start].ohm > ohm >= data->comp[end].ohm
 440                  *
 441                  * We could check for "ohm == data->comp[mid].ohm" here, but
 442                  * that is a quite unlikely condition, and we would have to
 443                  * check again after updating start. Check it at the end instead
 444                  * for simplicity.
 445                  */
 446                 if (ohm >= data->comp[mid].ohm) {
 447                         end = mid;
 448                 } else {
 449                         start = mid + 1;
 450                         /*
 451                          * ohm >= data->comp[start].ohm might be true here,
 452                          * since we set start to mid + 1. In that case, we are
 453                          * done. We could keep going, but the condition is quite
 454                          * likely to occur, so it is worth checking for it.
 455                          */
 456                         if (ohm >= data->comp[start].ohm)
 457                                 end = start;
 458                 }
 459                 /*
 460                  * start <= end
 461                  * data->comp[start].ohm >= ohm >= data->comp[end].ohm
 462                  */
 463         }
 464         /*
 465          * start == end
 466          * ohm >= data->comp[end].ohm
 467          */
 468         *i_low = end;
 469         if (ohm == data->comp[end].ohm)
 470                 *i_high = end;
 471         else
 472                 *i_high = end - 1;
 473 }
 474
 475 static int get_temp_mc(struct ntc_data *data, unsigned int ohm)
 476 {
 477         int low, high;
 478         int temp;
 479
 480         lookup_comp(data, ohm, &low, &high);
 481         if (low == high) {
 482                 /* Unable to use linear approximation */
 483                 temp = data->comp[low].temp_c * 1000;
 484         } else {
 485                 temp = data->comp[low].temp_c * 1000 +
 486                         ((data->comp[high].temp_c - data->comp[low].temp_c) *
 487                          1000 * ((int)ohm - (int)data->comp[low].ohm)) /
 488                         ((int)data->comp[high].ohm - (int)data->comp[low].ohm);
 489         }
 490         return temp;
 491 }
 492
 493 static int ntc_thermistor_get_ohm(struct ntc_data *data)
 494 {
 495         int read_uv;
 496
 497         if (data->pdata->read_ohm)
 498                 return data->pdata->read_ohm();
 499
 500         if (data->pdata->read_uv) {
 501                 read_uv = data->pdata->read_uv(data->pdata);
 502                 if (read_uv < 0)
 503                         return read_uv;
 504                 return get_ohm_of_thermistor(data, read_uv);
 505         }
 506         return -EINVAL;
 507 }
 508
 509 static int ntc_read_temp(void *data, int *temp)
 510 {
 511         int ohm;
 512
 513         ohm = ntc_thermistor_get_ohm(data);
 514         if (ohm < 0)
 515                 return ohm;
 516
 517         *temp = get_temp_mc(data, ohm);
 518
 519         return 0;
 520 }
 521
 522 static ssize_t ntc_show_type(struct device *dev,
 523                 struct device_attribute *attr, char *buf)
 524 {
 525         return sprintf(buf, "4\n");
 526 }
 527
 528 static ssize_t ntc_show_temp(struct device *dev,
 529                 struct device_attribute *attr, char *buf)
 530 {
 531         struct ntc_data *data = dev_get_drvdata(dev);
 532         int ohm;
 533
 534         ohm = ntc_thermistor_get_ohm(data);
 535         if (ohm < 0)
 536                 return ohm;
 537
 538         return sprintf(buf, "%d\n", get_temp_mc(data, ohm));
 539 }
 540
 541 static SENSOR_DEVICE_ATTR(temp1_type, S_IRUGO, ntc_show_type, NULL, 0);
 542 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ntc_show_temp, NULL, 0);
 543
 544 static struct attribute *ntc_attrs[] = {
 545         &sensor_dev_attr_temp1_type.dev_attr.attr,
 546         &sensor_dev_attr_temp1_input.dev_attr.attr,
 547         NULL,
 548 };
 549 ATTRIBUTE_GROUPS(ntc);
 550
 551 static const struct thermal_zone_of_device_ops ntc_of_thermal_ops = {
 552         .get_temp = ntc_read_temp,
 553 };
 554
 555 static int ntc_thermistor_probe(struct platform_device *pdev)
 556 {
 557         struct thermal_zone_device *tz;
 558         struct device *dev = &pdev->dev;
 559         const struct of_device_id *of_id =
 560                         of_match_device(of_match_ptr(ntc_match), dev);
 561         const struct platform_device_id *pdev_id;
 562         struct ntc_thermistor_platform_data *pdata;
 563         struct device *hwmon_dev;
 564         struct ntc_data *data;
 565
 566         pdata = ntc_thermistor_parse_dt(dev);
 567         if (IS_ERR(pdata))
 568                 return PTR_ERR(pdata);
 569         else if (pdata == NULL)
 570                 pdata = dev_get_platdata(dev);
 571
 572         if (!pdata) {
 573                 dev_err(dev, "No platform init data supplied.\n");
 574                 return -ENODEV;
 575         }
 576
 577         /* Either one of the two is required. */
 578         if (!pdata->read_uv && !pdata->read_ohm) {
 579                 dev_err(dev,
 580                         "Both read_uv and read_ohm missing. Need either one of the two.\n");
 581                 return -EINVAL;
 582         }
 583
 584         if (pdata->read_uv && pdata->read_ohm) {
 585                 dev_warn(dev,
 586                          "Only one of read_uv and read_ohm is needed; ignoring read_uv.\n");
 587                 pdata->read_uv = NULL;
 588         }
 589
 590         if (pdata->read_uv && (pdata->pullup_uv == 0 ||
 591                                 (pdata->pullup_ohm == 0 && pdata->connect ==
 592                                  NTC_CONNECTED_GROUND) ||
 593                                 (pdata->pulldown_ohm == 0 && pdata->connect ==
 594                                  NTC_CONNECTED_POSITIVE) ||
 595                                 (pdata->connect != NTC_CONNECTED_POSITIVE &&
 596                                  pdata->connect != NTC_CONNECTED_GROUND))) {
 597                 dev_err(dev, "Required data to use read_uv not supplied.\n");
 598                 return -EINVAL;
 599         }
 600
 601         data = devm_kzalloc(dev, sizeof(struct ntc_data), GFP_KERNEL);
 602         if (!data)
 603                 return -ENOMEM;
 604
 605         pdev_id = of_id ? of_id->data : platform_get_device_id(pdev);
 606
 607         data->pdata = pdata;
 608
 609         switch (pdev_id->driver_data) {
 610         case TYPE_NCPXXWB473:
 611                 data->comp = ncpXXwb473;
 612                 data->n_comp = ARRAY_SIZE(ncpXXwb473);
 613                 break;
 614         case TYPE_NCPXXWL333:
 615                 data->comp = ncpXXwl333;
 616                 data->n_comp = ARRAY_SIZE(ncpXXwl333);
 617                 break;
 618         case TYPE_B57330V2103:
 619                 data->comp = b57330v2103;
 620                 data->n_comp = ARRAY_SIZE(b57330v2103);
 621                 break;
 622         case TYPE_NCPXXWF104:
 623                 data->comp = ncpXXwf104;
 624                 data->n_comp = ARRAY_SIZE(ncpXXwf104);
 625                 break;
 626         case TYPE_NCPXXXH103:
 627                 data->comp = ncpXXxh103;
 628                 data->n_comp = ARRAY_SIZE(ncpXXxh103);
 629                 break;
 630         default:
 631                 dev_err(dev, "Unknown device type: %lu(%s)\n",
 632                                 pdev_id->driver_data, pdev_id->name);
 633                 return -EINVAL;
 634         }
 635
 636         hwmon_dev = devm_hwmon_device_register_with_groups(dev, pdev_id->name,
 637                                                            data, ntc_groups);
 638         if (IS_ERR(hwmon_dev)) {
 639                 dev_err(dev, "unable to register as hwmon device.\n");
 640                 return PTR_ERR(hwmon_dev);
 641         }
 642
 643         dev_info(dev, "Thermistor type: %s successfully probed.\n",
 644                  pdev_id->name);
 645
 646         tz = devm_thermal_zone_of_sensor_register(dev, 0, data,
 647                                                   &ntc_of_thermal_ops);
 648         if (IS_ERR(tz))
 649                 dev_dbg(dev, "Failed to register to thermal fw.\n");
 650
 651         return 0;
 652 }
 653
 654 static struct platform_driver ntc_thermistor_driver = {
 655         .driver = {
 656                 .name = "ntc-thermistor",
 657                 .of_match_table = of_match_ptr(ntc_match),
 658         },
 659         .probe = ntc_thermistor_probe,
 660         .id_table = ntc_thermistor_id,
 661 };
 662
 663 module_platform_driver(ntc_thermistor_driver);
 664
 665 MODULE_DESCRIPTION("NTC Thermistor Driver");
 666 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
 667 MODULE_LICENSE("GPL");
 668 MODULE_ALIAS("platform:ntc-thermistor");