jme: Do not enable NIC WoL functions on S0
[linux/fpc-iii.git] / drivers / hwmon / ntc_thermistor.c
blob387ea83783df520452f4caf4bd3fe6f42ac3de70
1 /*
2 * ntc_thermistor.c - NTC Thermistors
4 * Copyright (C) 2010 Samsung Electronics
5 * MyungJoo Ham <myungjoo.ham@samsung.com>
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.
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.
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
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>
32 #include <linux/platform_data/ntc_thermistor.h>
34 #include <linux/iio/iio.h>
35 #include <linux/iio/machine.h>
36 #include <linux/iio/driver.h>
37 #include <linux/iio/consumer.h>
39 #include <linux/hwmon.h>
40 #include <linux/hwmon-sysfs.h>
42 struct ntc_compensation {
43 int temp_c;
44 unsigned int ohm;
47 /* Order matters, ntc_match references the entries by index */
48 static const struct platform_device_id ntc_thermistor_id[] = {
49 { "ncp15wb473", TYPE_NCPXXWB473 },
50 { "ncp18wb473", TYPE_NCPXXWB473 },
51 { "ncp21wb473", TYPE_NCPXXWB473 },
52 { "ncp03wb473", TYPE_NCPXXWB473 },
53 { "ncp15wl333", TYPE_NCPXXWL333 },
54 { },
58 * A compensation table should be sorted by the values of .ohm
59 * in descending order.
60 * The following compensation tables are from the specification of Murata NTC
61 * Thermistors Datasheet
63 static const struct ntc_compensation ncpXXwb473[] = {
64 { .temp_c = -40, .ohm = 1747920 },
65 { .temp_c = -35, .ohm = 1245428 },
66 { .temp_c = -30, .ohm = 898485 },
67 { .temp_c = -25, .ohm = 655802 },
68 { .temp_c = -20, .ohm = 483954 },
69 { .temp_c = -15, .ohm = 360850 },
70 { .temp_c = -10, .ohm = 271697 },
71 { .temp_c = -5, .ohm = 206463 },
72 { .temp_c = 0, .ohm = 158214 },
73 { .temp_c = 5, .ohm = 122259 },
74 { .temp_c = 10, .ohm = 95227 },
75 { .temp_c = 15, .ohm = 74730 },
76 { .temp_c = 20, .ohm = 59065 },
77 { .temp_c = 25, .ohm = 47000 },
78 { .temp_c = 30, .ohm = 37643 },
79 { .temp_c = 35, .ohm = 30334 },
80 { .temp_c = 40, .ohm = 24591 },
81 { .temp_c = 45, .ohm = 20048 },
82 { .temp_c = 50, .ohm = 16433 },
83 { .temp_c = 55, .ohm = 13539 },
84 { .temp_c = 60, .ohm = 11209 },
85 { .temp_c = 65, .ohm = 9328 },
86 { .temp_c = 70, .ohm = 7798 },
87 { .temp_c = 75, .ohm = 6544 },
88 { .temp_c = 80, .ohm = 5518 },
89 { .temp_c = 85, .ohm = 4674 },
90 { .temp_c = 90, .ohm = 3972 },
91 { .temp_c = 95, .ohm = 3388 },
92 { .temp_c = 100, .ohm = 2902 },
93 { .temp_c = 105, .ohm = 2494 },
94 { .temp_c = 110, .ohm = 2150 },
95 { .temp_c = 115, .ohm = 1860 },
96 { .temp_c = 120, .ohm = 1615 },
97 { .temp_c = 125, .ohm = 1406 },
99 static const struct ntc_compensation ncpXXwl333[] = {
100 { .temp_c = -40, .ohm = 1610154 },
101 { .temp_c = -35, .ohm = 1130850 },
102 { .temp_c = -30, .ohm = 802609 },
103 { .temp_c = -25, .ohm = 575385 },
104 { .temp_c = -20, .ohm = 416464 },
105 { .temp_c = -15, .ohm = 304219 },
106 { .temp_c = -10, .ohm = 224193 },
107 { .temp_c = -5, .ohm = 166623 },
108 { .temp_c = 0, .ohm = 124850 },
109 { .temp_c = 5, .ohm = 94287 },
110 { .temp_c = 10, .ohm = 71747 },
111 { .temp_c = 15, .ohm = 54996 },
112 { .temp_c = 20, .ohm = 42455 },
113 { .temp_c = 25, .ohm = 33000 },
114 { .temp_c = 30, .ohm = 25822 },
115 { .temp_c = 35, .ohm = 20335 },
116 { .temp_c = 40, .ohm = 16115 },
117 { .temp_c = 45, .ohm = 12849 },
118 { .temp_c = 50, .ohm = 10306 },
119 { .temp_c = 55, .ohm = 8314 },
120 { .temp_c = 60, .ohm = 6746 },
121 { .temp_c = 65, .ohm = 5503 },
122 { .temp_c = 70, .ohm = 4513 },
123 { .temp_c = 75, .ohm = 3721 },
124 { .temp_c = 80, .ohm = 3084 },
125 { .temp_c = 85, .ohm = 2569 },
126 { .temp_c = 90, .ohm = 2151 },
127 { .temp_c = 95, .ohm = 1809 },
128 { .temp_c = 100, .ohm = 1529 },
129 { .temp_c = 105, .ohm = 1299 },
130 { .temp_c = 110, .ohm = 1108 },
131 { .temp_c = 115, .ohm = 949 },
132 { .temp_c = 120, .ohm = 817 },
133 { .temp_c = 125, .ohm = 707 },
136 struct ntc_data {
137 struct device *hwmon_dev;
138 struct ntc_thermistor_platform_data *pdata;
139 const struct ntc_compensation *comp;
140 struct device *dev;
141 int n_comp;
142 char name[PLATFORM_NAME_SIZE];
145 #if defined(CONFIG_OF) && IS_ENABLED(CONFIG_IIO)
146 static int ntc_adc_iio_read(struct ntc_thermistor_platform_data *pdata)
148 struct iio_channel *channel = pdata->chan;
149 s64 result;
150 int val, ret;
152 ret = iio_read_channel_raw(channel, &val);
153 if (ret < 0) {
154 pr_err("read channel() error: %d\n", ret);
155 return ret;
158 /* unit: mV */
159 result = pdata->pullup_uv * (s64) val;
160 result >>= 12;
162 return (int)result;
165 static const struct of_device_id ntc_match[] = {
166 { .compatible = "murata,ncp15wb473",
167 .data = &ntc_thermistor_id[0] },
168 { .compatible = "murata,ncp18wb473",
169 .data = &ntc_thermistor_id[1] },
170 { .compatible = "murata,ncp21wb473",
171 .data = &ntc_thermistor_id[2] },
172 { .compatible = "murata,ncp03wb473",
173 .data = &ntc_thermistor_id[3] },
174 { .compatible = "murata,ncp15wl333",
175 .data = &ntc_thermistor_id[4] },
177 /* Usage of vendor name "ntc" is deprecated */
178 { .compatible = "ntc,ncp15wb473",
179 .data = &ntc_thermistor_id[0] },
180 { .compatible = "ntc,ncp18wb473",
181 .data = &ntc_thermistor_id[1] },
182 { .compatible = "ntc,ncp21wb473",
183 .data = &ntc_thermistor_id[2] },
184 { .compatible = "ntc,ncp03wb473",
185 .data = &ntc_thermistor_id[3] },
186 { .compatible = "ntc,ncp15wl333",
187 .data = &ntc_thermistor_id[4] },
188 { },
190 MODULE_DEVICE_TABLE(of, ntc_match);
192 static struct ntc_thermistor_platform_data *
193 ntc_thermistor_parse_dt(struct platform_device *pdev)
195 struct iio_channel *chan;
196 enum iio_chan_type type;
197 struct device_node *np = pdev->dev.of_node;
198 struct ntc_thermistor_platform_data *pdata;
199 int ret;
201 if (!np)
202 return NULL;
204 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
205 if (!pdata)
206 return ERR_PTR(-ENOMEM);
208 chan = iio_channel_get(&pdev->dev, NULL);
209 if (IS_ERR(chan))
210 return ERR_CAST(chan);
212 ret = iio_get_channel_type(chan, &type);
213 if (ret < 0)
214 return ERR_PTR(ret);
216 if (type != IIO_VOLTAGE)
217 return ERR_PTR(-EINVAL);
219 if (of_property_read_u32(np, "pullup-uv", &pdata->pullup_uv))
220 return ERR_PTR(-ENODEV);
221 if (of_property_read_u32(np, "pullup-ohm", &pdata->pullup_ohm))
222 return ERR_PTR(-ENODEV);
223 if (of_property_read_u32(np, "pulldown-ohm", &pdata->pulldown_ohm))
224 return ERR_PTR(-ENODEV);
226 if (of_find_property(np, "connected-positive", NULL))
227 pdata->connect = NTC_CONNECTED_POSITIVE;
228 else /* status change should be possible if not always on. */
229 pdata->connect = NTC_CONNECTED_GROUND;
231 pdata->chan = chan;
232 pdata->read_uv = ntc_adc_iio_read;
234 return pdata;
236 static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata)
238 if (pdata->chan)
239 iio_channel_release(pdata->chan);
241 #else
242 static struct ntc_thermistor_platform_data *
243 ntc_thermistor_parse_dt(struct platform_device *pdev)
245 return NULL;
248 #define ntc_match NULL
250 static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata)
252 #endif
254 static inline u64 div64_u64_safe(u64 dividend, u64 divisor)
256 if (divisor == 0 && dividend == 0)
257 return 0;
258 if (divisor == 0)
259 return UINT_MAX;
260 return div64_u64(dividend, divisor);
263 static int get_ohm_of_thermistor(struct ntc_data *data, unsigned int uv)
265 struct ntc_thermistor_platform_data *pdata = data->pdata;
266 u64 mv = uv / 1000;
267 u64 pmv = pdata->pullup_uv / 1000;
268 u64 n, puo, pdo;
269 puo = pdata->pullup_ohm;
270 pdo = pdata->pulldown_ohm;
272 if (mv == 0) {
273 if (pdata->connect == NTC_CONNECTED_POSITIVE)
274 return INT_MAX;
275 return 0;
277 if (mv >= pmv)
278 return (pdata->connect == NTC_CONNECTED_POSITIVE) ?
279 0 : INT_MAX;
281 if (pdata->connect == NTC_CONNECTED_POSITIVE && puo == 0)
282 n = div64_u64_safe(pdo * (pmv - mv), mv);
283 else if (pdata->connect == NTC_CONNECTED_GROUND && pdo == 0)
284 n = div64_u64_safe(puo * mv, pmv - mv);
285 else if (pdata->connect == NTC_CONNECTED_POSITIVE)
286 n = div64_u64_safe(pdo * puo * (pmv - mv),
287 puo * mv - pdo * (pmv - mv));
288 else
289 n = div64_u64_safe(pdo * puo * mv, pdo * (pmv - mv) - puo * mv);
291 if (n > INT_MAX)
292 n = INT_MAX;
293 return n;
296 static void lookup_comp(struct ntc_data *data, unsigned int ohm,
297 int *i_low, int *i_high)
299 int start, end, mid;
302 * Handle special cases: Resistance is higher than or equal to
303 * resistance in first table entry, or resistance is lower or equal
304 * to resistance in last table entry.
305 * In these cases, return i_low == i_high, either pointing to the
306 * beginning or to the end of the table depending on the condition.
308 if (ohm >= data->comp[0].ohm) {
309 *i_low = 0;
310 *i_high = 0;
311 return;
313 if (ohm <= data->comp[data->n_comp - 1].ohm) {
314 *i_low = data->n_comp - 1;
315 *i_high = data->n_comp - 1;
316 return;
319 /* Do a binary search on compensation table */
320 start = 0;
321 end = data->n_comp;
322 while (start < end) {
323 mid = start + (end - start) / 2;
325 * start <= mid < end
326 * data->comp[start].ohm > ohm >= data->comp[end].ohm
328 * We could check for "ohm == data->comp[mid].ohm" here, but
329 * that is a quite unlikely condition, and we would have to
330 * check again after updating start. Check it at the end instead
331 * for simplicity.
333 if (ohm >= data->comp[mid].ohm) {
334 end = mid;
335 } else {
336 start = mid + 1;
338 * ohm >= data->comp[start].ohm might be true here,
339 * since we set start to mid + 1. In that case, we are
340 * done. We could keep going, but the condition is quite
341 * likely to occur, so it is worth checking for it.
343 if (ohm >= data->comp[start].ohm)
344 end = start;
347 * start <= end
348 * data->comp[start].ohm >= ohm >= data->comp[end].ohm
352 * start == end
353 * ohm >= data->comp[end].ohm
355 *i_low = end;
356 if (ohm == data->comp[end].ohm)
357 *i_high = end;
358 else
359 *i_high = end - 1;
362 static int get_temp_mc(struct ntc_data *data, unsigned int ohm)
364 int low, high;
365 int temp;
367 lookup_comp(data, ohm, &low, &high);
368 if (low == high) {
369 /* Unable to use linear approximation */
370 temp = data->comp[low].temp_c * 1000;
371 } else {
372 temp = data->comp[low].temp_c * 1000 +
373 ((data->comp[high].temp_c - data->comp[low].temp_c) *
374 1000 * ((int)ohm - (int)data->comp[low].ohm)) /
375 ((int)data->comp[high].ohm - (int)data->comp[low].ohm);
377 return temp;
380 static int ntc_thermistor_get_ohm(struct ntc_data *data)
382 int read_uv;
384 if (data->pdata->read_ohm)
385 return data->pdata->read_ohm();
387 if (data->pdata->read_uv) {
388 read_uv = data->pdata->read_uv(data->pdata);
389 if (read_uv < 0)
390 return read_uv;
391 return get_ohm_of_thermistor(data, read_uv);
393 return -EINVAL;
396 static ssize_t ntc_show_name(struct device *dev,
397 struct device_attribute *attr, char *buf)
399 struct ntc_data *data = dev_get_drvdata(dev);
401 return sprintf(buf, "%s\n", data->name);
404 static ssize_t ntc_show_type(struct device *dev,
405 struct device_attribute *attr, char *buf)
407 return sprintf(buf, "4\n");
410 static ssize_t ntc_show_temp(struct device *dev,
411 struct device_attribute *attr, char *buf)
413 struct ntc_data *data = dev_get_drvdata(dev);
414 int ohm;
416 ohm = ntc_thermistor_get_ohm(data);
417 if (ohm < 0)
418 return ohm;
420 return sprintf(buf, "%d\n", get_temp_mc(data, ohm));
423 static SENSOR_DEVICE_ATTR(temp1_type, S_IRUGO, ntc_show_type, NULL, 0);
424 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ntc_show_temp, NULL, 0);
425 static DEVICE_ATTR(name, S_IRUGO, ntc_show_name, NULL);
427 static struct attribute *ntc_attributes[] = {
428 &dev_attr_name.attr,
429 &sensor_dev_attr_temp1_type.dev_attr.attr,
430 &sensor_dev_attr_temp1_input.dev_attr.attr,
431 NULL,
434 static const struct attribute_group ntc_attr_group = {
435 .attrs = ntc_attributes,
438 static int ntc_thermistor_probe(struct platform_device *pdev)
440 const struct of_device_id *of_id =
441 of_match_device(of_match_ptr(ntc_match), &pdev->dev);
442 const struct platform_device_id *pdev_id;
443 struct ntc_thermistor_platform_data *pdata;
444 struct ntc_data *data;
445 int ret;
447 pdata = ntc_thermistor_parse_dt(pdev);
448 if (IS_ERR(pdata))
449 return PTR_ERR(pdata);
450 else if (pdata == NULL)
451 pdata = dev_get_platdata(&pdev->dev);
453 if (!pdata) {
454 dev_err(&pdev->dev, "No platform init data supplied.\n");
455 return -ENODEV;
458 /* Either one of the two is required. */
459 if (!pdata->read_uv && !pdata->read_ohm) {
460 dev_err(&pdev->dev,
461 "Both read_uv and read_ohm missing. Need either one of the two.\n");
462 return -EINVAL;
465 if (pdata->read_uv && pdata->read_ohm) {
466 dev_warn(&pdev->dev,
467 "Only one of read_uv and read_ohm is needed; ignoring read_uv.\n");
468 pdata->read_uv = NULL;
471 if (pdata->read_uv && (pdata->pullup_uv == 0 ||
472 (pdata->pullup_ohm == 0 && pdata->connect ==
473 NTC_CONNECTED_GROUND) ||
474 (pdata->pulldown_ohm == 0 && pdata->connect ==
475 NTC_CONNECTED_POSITIVE) ||
476 (pdata->connect != NTC_CONNECTED_POSITIVE &&
477 pdata->connect != NTC_CONNECTED_GROUND))) {
478 dev_err(&pdev->dev,
479 "Required data to use read_uv not supplied.\n");
480 return -EINVAL;
483 data = devm_kzalloc(&pdev->dev, sizeof(struct ntc_data), GFP_KERNEL);
484 if (!data)
485 return -ENOMEM;
487 pdev_id = of_id ? of_id->data : platform_get_device_id(pdev);
489 data->dev = &pdev->dev;
490 data->pdata = pdata;
491 strlcpy(data->name, pdev_id->name, sizeof(data->name));
493 switch (pdev_id->driver_data) {
494 case TYPE_NCPXXWB473:
495 data->comp = ncpXXwb473;
496 data->n_comp = ARRAY_SIZE(ncpXXwb473);
497 break;
498 case TYPE_NCPXXWL333:
499 data->comp = ncpXXwl333;
500 data->n_comp = ARRAY_SIZE(ncpXXwl333);
501 break;
502 default:
503 dev_err(&pdev->dev, "Unknown device type: %lu(%s)\n",
504 pdev_id->driver_data, pdev_id->name);
505 return -EINVAL;
508 platform_set_drvdata(pdev, data);
510 ret = sysfs_create_group(&data->dev->kobj, &ntc_attr_group);
511 if (ret) {
512 dev_err(data->dev, "unable to create sysfs files\n");
513 return ret;
516 data->hwmon_dev = hwmon_device_register(data->dev);
517 if (IS_ERR(data->hwmon_dev)) {
518 dev_err(data->dev, "unable to register as hwmon device.\n");
519 ret = PTR_ERR(data->hwmon_dev);
520 goto err_after_sysfs;
523 dev_info(&pdev->dev, "Thermistor type: %s successfully probed.\n",
524 pdev_id->name);
526 return 0;
527 err_after_sysfs:
528 sysfs_remove_group(&data->dev->kobj, &ntc_attr_group);
529 ntc_iio_channel_release(pdata);
530 return ret;
533 static int ntc_thermistor_remove(struct platform_device *pdev)
535 struct ntc_data *data = platform_get_drvdata(pdev);
536 struct ntc_thermistor_platform_data *pdata = data->pdata;
538 hwmon_device_unregister(data->hwmon_dev);
539 sysfs_remove_group(&data->dev->kobj, &ntc_attr_group);
540 ntc_iio_channel_release(pdata);
542 return 0;
545 static struct platform_driver ntc_thermistor_driver = {
546 .driver = {
547 .name = "ntc-thermistor",
548 .owner = THIS_MODULE,
549 .of_match_table = of_match_ptr(ntc_match),
551 .probe = ntc_thermistor_probe,
552 .remove = ntc_thermistor_remove,
553 .id_table = ntc_thermistor_id,
556 module_platform_driver(ntc_thermistor_driver);
558 MODULE_DESCRIPTION("NTC Thermistor Driver from Murata");
559 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
560 MODULE_LICENSE("GPL");
561 MODULE_ALIAS("platform:ntc-thermistor");