1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Texas Instruments TMP108 SMBus temperature sensor driver
3 *
4 * Copyright (C) 2016 John Muir <[email protected]>
5 */
6
7 #include <linux/delay.h>
8 #include <linux/device.h>
9 #include <linux/err.h>
10 #include <linux/hwmon.h>
11 #include <linux/mod_devicetable.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/i2c.h>
15 #include <linux/i3c/device.h>
16 #include <linux/init.h>
17 #include <linux/jiffies.h>
18 #include <linux/regmap.h>
19 #include <linux/regulator/consumer.h>
20 #include <linux/slab.h>
21
22 #define DRIVER_NAME "tmp108"
23
24 #define TMP108_REG_TEMP 0x00
25 #define TMP108_REG_CONF 0x01
26 #define TMP108_REG_TLOW 0x02
27 #define TMP108_REG_THIGH 0x03
28
29 #define TMP108_TEMP_MIN_MC -50000 /* Minimum millicelcius. */
30 #define TMP108_TEMP_MAX_MC 127937 /* Maximum millicelcius. */
31
32 /* Configuration register bits.
33 * Note: these bit definitions are byte swapped.
34 */
35 #define TMP108_CONF_M0 0x0100 /* Sensor mode. */
36 #define TMP108_CONF_M1 0x0200
37 #define TMP108_CONF_TM 0x0400 /* Thermostat mode. */
38 #define TMP108_CONF_FL 0x0800 /* Watchdog flag - TLOW */
39 #define TMP108_CONF_FH 0x1000 /* Watchdog flag - THIGH */
40 #define TMP108_CONF_CR0 0x2000 /* Conversion rate. */
41 #define TMP108_CONF_CR1 0x4000
42 #define TMP108_CONF_ID 0x8000
43 #define TMP108_CONF_HYS0 0x0010 /* Hysteresis. */
44 #define TMP108_CONF_HYS1 0x0020
45 #define TMP108_CONF_POL 0x0080 /* Polarity of alert. */
46
47 /* Defaults set by the hardware upon reset. */
48 #define TMP108_CONF_DEFAULTS (TMP108_CONF_CR0 | TMP108_CONF_TM |\
49 TMP108_CONF_HYS0 | TMP108_CONF_M1)
50 /* These bits are read-only. */
51 #define TMP108_CONF_READ_ONLY (TMP108_CONF_FL | TMP108_CONF_FH |\
52 TMP108_CONF_ID)
53
54 #define TMP108_CONF_MODE_MASK (TMP108_CONF_M0|TMP108_CONF_M1)
55 #define TMP108_MODE_SHUTDOWN 0x0000
56 #define TMP108_MODE_ONE_SHOT TMP108_CONF_M0
57 #define TMP108_MODE_CONTINUOUS TMP108_CONF_M1 /* Default */
58 /* When M1 is set, M0 is ignored. */
59
60 #define TMP108_CONF_CONVRATE_MASK (TMP108_CONF_CR0|TMP108_CONF_CR1)
61 #define TMP108_CONVRATE_0P25HZ 0x0000
62 #define TMP108_CONVRATE_1HZ TMP108_CONF_CR0 /* Default */
63 #define TMP108_CONVRATE_4HZ TMP108_CONF_CR1
64 #define TMP108_CONVRATE_16HZ (TMP108_CONF_CR0|TMP108_CONF_CR1)
65
66 #define TMP108_CONF_HYSTERESIS_MASK (TMP108_CONF_HYS0|TMP108_CONF_HYS1)
67 #define TMP108_HYSTERESIS_0C 0x0000
68 #define TMP108_HYSTERESIS_1C TMP108_CONF_HYS0 /* Default */
69 #define TMP108_HYSTERESIS_2C TMP108_CONF_HYS1
70 #define TMP108_HYSTERESIS_4C (TMP108_CONF_HYS0|TMP108_CONF_HYS1)
71
72 #define TMP108_CONVERSION_TIME_MS 30 /* in milli-seconds */
73
74 struct tmp108 {
75 struct regmap *regmap;
76 u16 orig_config;
77 unsigned long ready_time;
78 };
79
80 /* convert 12-bit TMP108 register value to milliCelsius */
tmp108_temp_reg_to_mC(s16 val)81 static inline int tmp108_temp_reg_to_mC(s16 val)
82 {
83 return (val & ~0x0f) * 1000 / 256;
84 }
85
86 /* convert milliCelsius to left adjusted 12-bit TMP108 register value */
tmp108_mC_to_temp_reg(int val)87 static inline u16 tmp108_mC_to_temp_reg(int val)
88 {
89 return (val * 256) / 1000;
90 }
91
tmp108_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * temp)92 static int tmp108_read(struct device *dev, enum hwmon_sensor_types type,
93 u32 attr, int channel, long *temp)
94 {
95 struct tmp108 *tmp108 = dev_get_drvdata(dev);
96 unsigned int regval;
97 int err, hyst;
98
99 if (type == hwmon_chip) {
100 if (attr == hwmon_chip_update_interval) {
101 err = regmap_read(tmp108->regmap, TMP108_REG_CONF,
102 ®val);
103 if (err < 0)
104 return err;
105 switch (regval & TMP108_CONF_CONVRATE_MASK) {
106 case TMP108_CONVRATE_0P25HZ:
107 default:
108 *temp = 4000;
109 break;
110 case TMP108_CONVRATE_1HZ:
111 *temp = 1000;
112 break;
113 case TMP108_CONVRATE_4HZ:
114 *temp = 250;
115 break;
116 case TMP108_CONVRATE_16HZ:
117 *temp = 63;
118 break;
119 }
120 return 0;
121 }
122 return -EOPNOTSUPP;
123 }
124
125 switch (attr) {
126 case hwmon_temp_input:
127 /* Is it too early to return a conversion ? */
128 if (time_before(jiffies, tmp108->ready_time)) {
129 dev_dbg(dev, "%s: Conversion not ready yet..\n",
130 __func__);
131 return -EAGAIN;
132 }
133 err = regmap_read(tmp108->regmap, TMP108_REG_TEMP, ®val);
134 if (err < 0)
135 return err;
136 *temp = tmp108_temp_reg_to_mC(regval);
137 break;
138 case hwmon_temp_min:
139 case hwmon_temp_max:
140 err = regmap_read(tmp108->regmap, attr == hwmon_temp_min ?
141 TMP108_REG_TLOW : TMP108_REG_THIGH, ®val);
142 if (err < 0)
143 return err;
144 *temp = tmp108_temp_reg_to_mC(regval);
145 break;
146 case hwmon_temp_min_alarm:
147 case hwmon_temp_max_alarm:
148 err = regmap_read(tmp108->regmap, TMP108_REG_CONF, ®val);
149 if (err < 0)
150 return err;
151 *temp = !!(regval & (attr == hwmon_temp_min_alarm ?
152 TMP108_CONF_FL : TMP108_CONF_FH));
153 break;
154 case hwmon_temp_min_hyst:
155 case hwmon_temp_max_hyst:
156 err = regmap_read(tmp108->regmap, TMP108_REG_CONF, ®val);
157 if (err < 0)
158 return err;
159 switch (regval & TMP108_CONF_HYSTERESIS_MASK) {
160 case TMP108_HYSTERESIS_0C:
161 default:
162 hyst = 0;
163 break;
164 case TMP108_HYSTERESIS_1C:
165 hyst = 1000;
166 break;
167 case TMP108_HYSTERESIS_2C:
168 hyst = 2000;
169 break;
170 case TMP108_HYSTERESIS_4C:
171 hyst = 4000;
172 break;
173 }
174 err = regmap_read(tmp108->regmap, attr == hwmon_temp_min_hyst ?
175 TMP108_REG_TLOW : TMP108_REG_THIGH, ®val);
176 if (err < 0)
177 return err;
178 *temp = tmp108_temp_reg_to_mC(regval);
179 if (attr == hwmon_temp_min_hyst)
180 *temp += hyst;
181 else
182 *temp -= hyst;
183 break;
184 default:
185 return -EOPNOTSUPP;
186 }
187
188 return 0;
189 }
190
tmp108_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long temp)191 static int tmp108_write(struct device *dev, enum hwmon_sensor_types type,
192 u32 attr, int channel, long temp)
193 {
194 struct tmp108 *tmp108 = dev_get_drvdata(dev);
195 u32 regval, mask;
196 int err;
197
198 if (type == hwmon_chip) {
199 if (attr == hwmon_chip_update_interval) {
200 if (temp < 156)
201 mask = TMP108_CONVRATE_16HZ;
202 else if (temp < 625)
203 mask = TMP108_CONVRATE_4HZ;
204 else if (temp < 2500)
205 mask = TMP108_CONVRATE_1HZ;
206 else
207 mask = TMP108_CONVRATE_0P25HZ;
208 return regmap_update_bits(tmp108->regmap,
209 TMP108_REG_CONF,
210 TMP108_CONF_CONVRATE_MASK,
211 mask);
212 }
213 return -EOPNOTSUPP;
214 }
215
216 switch (attr) {
217 case hwmon_temp_min:
218 case hwmon_temp_max:
219 temp = clamp_val(temp, TMP108_TEMP_MIN_MC, TMP108_TEMP_MAX_MC);
220 return regmap_write(tmp108->regmap,
221 attr == hwmon_temp_min ?
222 TMP108_REG_TLOW : TMP108_REG_THIGH,
223 tmp108_mC_to_temp_reg(temp));
224 case hwmon_temp_min_hyst:
225 case hwmon_temp_max_hyst:
226 temp = clamp_val(temp, TMP108_TEMP_MIN_MC, TMP108_TEMP_MAX_MC);
227 err = regmap_read(tmp108->regmap,
228 attr == hwmon_temp_min_hyst ?
229 TMP108_REG_TLOW : TMP108_REG_THIGH,
230 ®val);
231 if (err < 0)
232 return err;
233 if (attr == hwmon_temp_min_hyst)
234 temp -= tmp108_temp_reg_to_mC(regval);
235 else
236 temp = tmp108_temp_reg_to_mC(regval) - temp;
237 if (temp < 500)
238 mask = TMP108_HYSTERESIS_0C;
239 else if (temp < 1500)
240 mask = TMP108_HYSTERESIS_1C;
241 else if (temp < 3000)
242 mask = TMP108_HYSTERESIS_2C;
243 else
244 mask = TMP108_HYSTERESIS_4C;
245 return regmap_update_bits(tmp108->regmap, TMP108_REG_CONF,
246 TMP108_CONF_HYSTERESIS_MASK, mask);
247 default:
248 return -EOPNOTSUPP;
249 }
250 }
251
tmp108_is_visible(const void * data,enum hwmon_sensor_types type,u32 attr,int channel)252 static umode_t tmp108_is_visible(const void *data, enum hwmon_sensor_types type,
253 u32 attr, int channel)
254 {
255 if (type == hwmon_chip && attr == hwmon_chip_update_interval)
256 return 0644;
257
258 if (type != hwmon_temp)
259 return 0;
260
261 switch (attr) {
262 case hwmon_temp_input:
263 case hwmon_temp_min_alarm:
264 case hwmon_temp_max_alarm:
265 return 0444;
266 case hwmon_temp_min:
267 case hwmon_temp_max:
268 case hwmon_temp_min_hyst:
269 case hwmon_temp_max_hyst:
270 return 0644;
271 default:
272 return 0;
273 }
274 }
275
276 static const struct hwmon_channel_info * const tmp108_info[] = {
277 HWMON_CHANNEL_INFO(chip,
278 HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL),
279 HWMON_CHANNEL_INFO(temp,
280 HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN |
281 HWMON_T_MIN_HYST | HWMON_T_MAX_HYST |
282 HWMON_T_MIN_ALARM | HWMON_T_MAX_ALARM),
283 NULL
284 };
285
286 static const struct hwmon_ops tmp108_hwmon_ops = {
287 .is_visible = tmp108_is_visible,
288 .read = tmp108_read,
289 .write = tmp108_write,
290 };
291
292 static const struct hwmon_chip_info tmp108_chip_info = {
293 .ops = &tmp108_hwmon_ops,
294 .info = tmp108_info,
295 };
296
tmp108_restore_config(void * data)297 static void tmp108_restore_config(void *data)
298 {
299 struct tmp108 *tmp108 = data;
300
301 regmap_write(tmp108->regmap, TMP108_REG_CONF, tmp108->orig_config);
302 }
303
tmp108_is_writeable_reg(struct device * dev,unsigned int reg)304 static bool tmp108_is_writeable_reg(struct device *dev, unsigned int reg)
305 {
306 return reg != TMP108_REG_TEMP;
307 }
308
tmp108_is_volatile_reg(struct device * dev,unsigned int reg)309 static bool tmp108_is_volatile_reg(struct device *dev, unsigned int reg)
310 {
311 /* Configuration register must be volatile to enable FL and FH. */
312 return reg == TMP108_REG_TEMP || reg == TMP108_REG_CONF;
313 }
314
315 static const struct regmap_config tmp108_regmap_config = {
316 .reg_bits = 8,
317 .val_bits = 16,
318 .max_register = TMP108_REG_THIGH,
319 .writeable_reg = tmp108_is_writeable_reg,
320 .volatile_reg = tmp108_is_volatile_reg,
321 .val_format_endian = REGMAP_ENDIAN_BIG,
322 .cache_type = REGCACHE_MAPLE,
323 .use_single_read = true,
324 .use_single_write = true,
325 };
326
tmp108_common_probe(struct device * dev,struct regmap * regmap,char * name)327 static int tmp108_common_probe(struct device *dev, struct regmap *regmap, char *name)
328 {
329 struct device *hwmon_dev;
330 struct tmp108 *tmp108;
331 u32 config;
332 int err;
333
334 err = devm_regulator_get_enable(dev, "vcc");
335 if (err)
336 return dev_err_probe(dev, err, "Failed to enable regulator\n");
337
338 tmp108 = devm_kzalloc(dev, sizeof(*tmp108), GFP_KERNEL);
339 if (!tmp108)
340 return -ENOMEM;
341
342 dev_set_drvdata(dev, tmp108);
343 tmp108->regmap = regmap;
344
345 err = regmap_read(tmp108->regmap, TMP108_REG_CONF, &config);
346 if (err < 0) {
347 dev_err(dev, "error reading config register: %d", err);
348 return err;
349 }
350 tmp108->orig_config = config;
351
352 /* Only continuous mode is supported. */
353 config &= ~TMP108_CONF_MODE_MASK;
354 config |= TMP108_MODE_CONTINUOUS;
355
356 /* Only comparator mode is supported. */
357 config &= ~TMP108_CONF_TM;
358
359 err = regmap_write(tmp108->regmap, TMP108_REG_CONF, config);
360 if (err < 0) {
361 dev_err(dev, "error writing config register: %d", err);
362 return err;
363 }
364
365 tmp108->ready_time = jiffies;
366 if ((tmp108->orig_config & TMP108_CONF_MODE_MASK) ==
367 TMP108_MODE_SHUTDOWN)
368 tmp108->ready_time +=
369 msecs_to_jiffies(TMP108_CONVERSION_TIME_MS);
370
371 err = devm_add_action_or_reset(dev, tmp108_restore_config, tmp108);
372 if (err) {
373 dev_err(dev, "add action or reset failed: %d", err);
374 return err;
375 }
376
377 hwmon_dev = devm_hwmon_device_register_with_info(dev, name,
378 tmp108,
379 &tmp108_chip_info,
380 NULL);
381 return PTR_ERR_OR_ZERO(hwmon_dev);
382 }
383
tmp108_probe(struct i2c_client * client)384 static int tmp108_probe(struct i2c_client *client)
385 {
386 struct device *dev = &client->dev;
387 struct regmap *regmap;
388
389 if (!i2c_check_functionality(client->adapter,
390 I2C_FUNC_SMBUS_WORD_DATA))
391 return dev_err_probe(dev, -ENODEV,
392 "adapter doesn't support SMBus word transactions\n");
393
394 regmap = devm_regmap_init_i2c(client, &tmp108_regmap_config);
395 if (IS_ERR(regmap))
396 return dev_err_probe(dev, PTR_ERR(regmap), "regmap init failed");
397
398 return tmp108_common_probe(dev, regmap, client->name);
399 }
400
tmp108_suspend(struct device * dev)401 static int tmp108_suspend(struct device *dev)
402 {
403 struct tmp108 *tmp108 = dev_get_drvdata(dev);
404
405 return regmap_update_bits(tmp108->regmap, TMP108_REG_CONF,
406 TMP108_CONF_MODE_MASK, TMP108_MODE_SHUTDOWN);
407 }
408
tmp108_resume(struct device * dev)409 static int tmp108_resume(struct device *dev)
410 {
411 struct tmp108 *tmp108 = dev_get_drvdata(dev);
412 int err;
413
414 err = regmap_update_bits(tmp108->regmap, TMP108_REG_CONF,
415 TMP108_CONF_MODE_MASK, TMP108_MODE_CONTINUOUS);
416 tmp108->ready_time = jiffies +
417 msecs_to_jiffies(TMP108_CONVERSION_TIME_MS);
418 return err;
419 }
420
421 static DEFINE_SIMPLE_DEV_PM_OPS(tmp108_dev_pm_ops, tmp108_suspend, tmp108_resume);
422
423 static const struct i2c_device_id tmp108_i2c_ids[] = {
424 { "p3t1085" },
425 { "tmp108" },
426 { }
427 };
428 MODULE_DEVICE_TABLE(i2c, tmp108_i2c_ids);
429
430 static const struct of_device_id tmp108_of_ids[] = {
431 { .compatible = "nxp,p3t1085", },
432 { .compatible = "ti,tmp108", },
433 {}
434 };
435 MODULE_DEVICE_TABLE(of, tmp108_of_ids);
436
437 static struct i2c_driver tmp108_driver = {
438 .driver = {
439 .name = DRIVER_NAME,
440 .pm = pm_sleep_ptr(&tmp108_dev_pm_ops),
441 .of_match_table = tmp108_of_ids,
442 },
443 .probe = tmp108_probe,
444 .id_table = tmp108_i2c_ids,
445 };
446
447 static const struct i3c_device_id p3t1085_i3c_ids[] = {
448 I3C_DEVICE(0x011b, 0x1529, NULL),
449 {}
450 };
451 MODULE_DEVICE_TABLE(i3c, p3t1085_i3c_ids);
452
p3t1085_i3c_probe(struct i3c_device * i3cdev)453 static int p3t1085_i3c_probe(struct i3c_device *i3cdev)
454 {
455 struct device *dev = i3cdev_to_dev(i3cdev);
456 struct regmap *regmap;
457
458 regmap = devm_regmap_init_i3c(i3cdev, &tmp108_regmap_config);
459 if (IS_ERR(regmap))
460 return dev_err_probe(dev, PTR_ERR(regmap),
461 "Failed to register i3c regmap\n");
462
463 return tmp108_common_probe(dev, regmap, "p3t1085_i3c");
464 }
465
466 static struct i3c_driver p3t1085_driver = {
467 .driver = {
468 .name = "p3t1085_i3c",
469 },
470 .probe = p3t1085_i3c_probe,
471 .id_table = p3t1085_i3c_ids,
472 };
473
474 module_i3c_i2c_driver(p3t1085_driver, &tmp108_driver)
475
476 MODULE_AUTHOR("John Muir <[email protected]>");
477 MODULE_DESCRIPTION("Texas Instruments TMP108 temperature sensor driver");
478 MODULE_LICENSE("GPL");
479