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c942fddf | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
7f07ec0f | 2 | /* |
3 | * STTS751 sensor driver | |
4 | * | |
5 | * Copyright (C) 2016-2017 Istituto Italiano di Tecnologia - RBCS - EDL | |
6 | * Robotics, Brain and Cognitive Sciences department | |
7 | * Electronic Design Laboratory | |
8 | * | |
9 | * Written by Andrea Merello <andrea.merello@gmail.com> | |
10 | * | |
11 | * Based on LM95241 driver and LM90 driver | |
7f07ec0f | 12 | */ |
13 | ||
14 | #include <linux/bitops.h> | |
15 | #include <linux/err.h> | |
16 | #include <linux/hwmon.h> | |
17 | #include <linux/hwmon-sysfs.h> | |
18 | #include <linux/i2c.h> | |
19 | #include <linux/init.h> | |
20 | #include <linux/interrupt.h> | |
21 | #include <linux/jiffies.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/mutex.h> | |
24 | #include <linux/property.h> | |
25 | #include <linux/slab.h> | |
26 | #include <linux/sysfs.h> | |
27 | #include <linux/util_macros.h> | |
28 | ||
29 | #define DEVNAME "stts751" | |
30 | ||
31 | static const unsigned short normal_i2c[] = { | |
32 | 0x48, 0x49, 0x38, 0x39, /* STTS751-0 */ | |
33 | 0x4A, 0x4B, 0x3A, 0x3B, /* STTS751-1 */ | |
34 | I2C_CLIENT_END }; | |
35 | ||
36 | #define STTS751_REG_TEMP_H 0x00 | |
37 | #define STTS751_REG_STATUS 0x01 | |
38 | #define STTS751_STATUS_TRIPT BIT(0) | |
39 | #define STTS751_STATUS_TRIPL BIT(5) | |
40 | #define STTS751_STATUS_TRIPH BIT(6) | |
41 | #define STTS751_REG_TEMP_L 0x02 | |
42 | #define STTS751_REG_CONF 0x03 | |
43 | #define STTS751_CONF_RES_MASK 0x0C | |
44 | #define STTS751_CONF_RES_SHIFT 2 | |
45 | #define STTS751_CONF_EVENT_DIS BIT(7) | |
46 | #define STTS751_CONF_STOP BIT(6) | |
47 | #define STTS751_REG_RATE 0x04 | |
48 | #define STTS751_REG_HLIM_H 0x05 | |
49 | #define STTS751_REG_HLIM_L 0x06 | |
50 | #define STTS751_REG_LLIM_H 0x07 | |
51 | #define STTS751_REG_LLIM_L 0x08 | |
52 | #define STTS751_REG_TLIM 0x20 | |
53 | #define STTS751_REG_HYST 0x21 | |
54 | #define STTS751_REG_SMBUS_TO 0x22 | |
55 | ||
56 | #define STTS751_REG_PROD_ID 0xFD | |
57 | #define STTS751_REG_MAN_ID 0xFE | |
58 | #define STTS751_REG_REV_ID 0xFF | |
59 | ||
60 | #define STTS751_0_PROD_ID 0x00 | |
61 | #define STTS751_1_PROD_ID 0x01 | |
62 | #define ST_MAN_ID 0x53 | |
63 | ||
64 | /* | |
65 | * Possible update intervals are (in mS): | |
66 | * 16000, 8000, 4000, 2000, 1000, 500, 250, 125, 62.5, 31.25 | |
67 | * However we are not going to complicate things too much and we stick to the | |
68 | * approx value in mS. | |
69 | */ | |
70 | static const int stts751_intervals[] = { | |
71 | 16000, 8000, 4000, 2000, 1000, 500, 250, 125, 63, 31 | |
72 | }; | |
73 | ||
74 | static const struct i2c_device_id stts751_id[] = { | |
d8a66f36 | 75 | { "stts751" }, |
7f07ec0f | 76 | { } |
77 | }; | |
78 | ||
1cbee124 | 79 | static const struct of_device_id __maybe_unused stts751_of_match[] = { |
1c1a7b75 JMC |
80 | { .compatible = "stts751" }, |
81 | { }, | |
82 | }; | |
83 | MODULE_DEVICE_TABLE(of, stts751_of_match); | |
84 | ||
7f07ec0f | 85 | struct stts751_priv { |
86 | struct device *dev; | |
87 | struct i2c_client *client; | |
88 | struct mutex access_lock; | |
89 | u8 interval; | |
90 | int res; | |
91 | int event_max, event_min; | |
92 | int therm; | |
93 | int hyst; | |
7f07ec0f | 94 | int temp; |
95 | unsigned long last_update, last_alert_update; | |
96 | u8 config; | |
97 | bool min_alert, max_alert, therm_trip; | |
98 | bool data_valid, alert_valid; | |
99 | bool notify_max, notify_min; | |
100 | }; | |
101 | ||
102 | /* | |
103 | * These functions converts temperature from HW format to integer format and | |
104 | * vice-vers. They are (mostly) taken from lm90 driver. Unit is in mC. | |
105 | */ | |
106 | static int stts751_to_deg(s16 hw_val) | |
107 | { | |
108 | return hw_val * 125 / 32; | |
109 | } | |
110 | ||
111 | static s32 stts751_to_hw(int val) | |
112 | { | |
113 | return DIV_ROUND_CLOSEST(val, 125) * 32; | |
114 | } | |
115 | ||
116 | static int stts751_adjust_resolution(struct stts751_priv *priv) | |
117 | { | |
118 | u8 res; | |
119 | ||
120 | switch (priv->interval) { | |
121 | case 9: | |
122 | /* 10 bits */ | |
123 | res = 0; | |
124 | break; | |
125 | case 8: | |
126 | /* 11 bits */ | |
127 | res = 1; | |
128 | break; | |
129 | default: | |
130 | /* 12 bits */ | |
131 | res = 3; | |
132 | break; | |
133 | } | |
134 | ||
135 | if (priv->res == res) | |
136 | return 0; | |
137 | ||
138 | priv->config &= ~STTS751_CONF_RES_MASK; | |
139 | priv->config |= res << STTS751_CONF_RES_SHIFT; | |
140 | dev_dbg(&priv->client->dev, "setting res %d. config %x", | |
141 | res, priv->config); | |
142 | priv->res = res; | |
143 | ||
144 | return i2c_smbus_write_byte_data(priv->client, | |
145 | STTS751_REG_CONF, priv->config); | |
146 | } | |
147 | ||
148 | static int stts751_update_temp(struct stts751_priv *priv) | |
149 | { | |
150 | s32 integer1, integer2, frac; | |
151 | ||
152 | /* | |
153 | * There is a trick here, like in the lm90 driver. We have to read two | |
154 | * registers to get the sensor temperature, but we have to beware a | |
155 | * conversion could occur between the readings. We could use the | |
156 | * one-shot conversion register, but we don't want to do this (disables | |
157 | * hardware monitoring). So the solution used here is to read the high | |
158 | * byte once, then the low byte, then the high byte again. If the new | |
159 | * high byte matches the old one, then we have a valid reading. Else we | |
160 | * have to read the low byte again, and now we believe we have a correct | |
161 | * reading. | |
162 | */ | |
163 | integer1 = i2c_smbus_read_byte_data(priv->client, STTS751_REG_TEMP_H); | |
164 | if (integer1 < 0) { | |
165 | dev_dbg(&priv->client->dev, | |
166 | "I2C read failed (temp H). ret: %x\n", integer1); | |
167 | return integer1; | |
168 | } | |
169 | ||
170 | frac = i2c_smbus_read_byte_data(priv->client, STTS751_REG_TEMP_L); | |
171 | if (frac < 0) { | |
172 | dev_dbg(&priv->client->dev, | |
173 | "I2C read failed (temp L). ret: %x\n", frac); | |
174 | return frac; | |
175 | } | |
176 | ||
177 | integer2 = i2c_smbus_read_byte_data(priv->client, STTS751_REG_TEMP_H); | |
178 | if (integer2 < 0) { | |
179 | dev_dbg(&priv->client->dev, | |
180 | "I2C 2nd read failed (temp H). ret: %x\n", integer2); | |
181 | return integer2; | |
182 | } | |
183 | ||
184 | if (integer1 != integer2) { | |
185 | frac = i2c_smbus_read_byte_data(priv->client, | |
186 | STTS751_REG_TEMP_L); | |
187 | if (frac < 0) { | |
188 | dev_dbg(&priv->client->dev, | |
189 | "I2C 2nd read failed (temp L). ret: %x\n", | |
190 | frac); | |
191 | return frac; | |
192 | } | |
193 | } | |
194 | ||
195 | priv->temp = stts751_to_deg((integer1 << 8) | frac); | |
196 | return 0; | |
197 | } | |
198 | ||
199 | static int stts751_set_temp_reg16(struct stts751_priv *priv, int temp, | |
200 | u8 hreg, u8 lreg) | |
201 | { | |
202 | s32 hwval; | |
203 | int ret; | |
204 | ||
205 | hwval = stts751_to_hw(temp); | |
206 | ||
207 | ret = i2c_smbus_write_byte_data(priv->client, hreg, hwval >> 8); | |
208 | if (ret) | |
209 | return ret; | |
210 | ||
211 | return i2c_smbus_write_byte_data(priv->client, lreg, hwval & 0xff); | |
212 | } | |
213 | ||
214 | static int stts751_set_temp_reg8(struct stts751_priv *priv, int temp, u8 reg) | |
215 | { | |
216 | s32 hwval; | |
217 | ||
218 | hwval = stts751_to_hw(temp); | |
219 | return i2c_smbus_write_byte_data(priv->client, reg, hwval >> 8); | |
220 | } | |
221 | ||
222 | static int stts751_read_reg16(struct stts751_priv *priv, int *temp, | |
223 | u8 hreg, u8 lreg) | |
224 | { | |
225 | int integer, frac; | |
226 | ||
227 | integer = i2c_smbus_read_byte_data(priv->client, hreg); | |
228 | if (integer < 0) | |
229 | return integer; | |
230 | ||
231 | frac = i2c_smbus_read_byte_data(priv->client, lreg); | |
232 | if (frac < 0) | |
233 | return frac; | |
234 | ||
235 | *temp = stts751_to_deg((integer << 8) | frac); | |
236 | ||
237 | return 0; | |
238 | } | |
239 | ||
240 | static int stts751_read_reg8(struct stts751_priv *priv, int *temp, u8 reg) | |
241 | { | |
242 | int integer; | |
243 | ||
244 | integer = i2c_smbus_read_byte_data(priv->client, reg); | |
245 | if (integer < 0) | |
246 | return integer; | |
247 | ||
248 | *temp = stts751_to_deg(integer << 8); | |
249 | ||
250 | return 0; | |
251 | } | |
252 | ||
253 | /* | |
254 | * Update alert flags without waiting for cache to expire. We detects alerts | |
255 | * immediately for the sake of the alert handler; we still need to deal with | |
256 | * caching to workaround the fact that alarm flags int the status register, | |
257 | * despite what the datasheet claims, gets always cleared on read. | |
258 | */ | |
259 | static int stts751_update_alert(struct stts751_priv *priv) | |
260 | { | |
261 | int ret; | |
262 | bool conv_done; | |
263 | int cache_time = msecs_to_jiffies(stts751_intervals[priv->interval]); | |
264 | ||
265 | /* | |
266 | * Add another 10% because if we run faster than the HW conversion | |
267 | * rate we will end up in reporting incorrectly alarms. | |
268 | */ | |
269 | cache_time += cache_time / 10; | |
270 | ||
271 | ret = i2c_smbus_read_byte_data(priv->client, STTS751_REG_STATUS); | |
272 | if (ret < 0) | |
273 | return ret; | |
274 | ||
275 | dev_dbg(&priv->client->dev, "status reg %x\n", ret); | |
276 | conv_done = ret & (STTS751_STATUS_TRIPH | STTS751_STATUS_TRIPL); | |
277 | /* | |
278 | * Reset the cache if the cache time expired, or if we are sure | |
279 | * we have valid data from a device conversion, or if we know | |
280 | * our cache has been never written. | |
281 | * | |
282 | * Note that when the cache has been never written the point is | |
283 | * to correctly initialize the timestamp, rather than clearing | |
284 | * the cache values. | |
285 | * | |
286 | * Note that updating the cache timestamp when we get an alarm flag | |
287 | * is required, otherwise we could incorrectly report alarms to be zero. | |
288 | */ | |
289 | if (time_after(jiffies, priv->last_alert_update + cache_time) || | |
290 | conv_done || !priv->alert_valid) { | |
291 | priv->max_alert = false; | |
292 | priv->min_alert = false; | |
293 | priv->alert_valid = true; | |
294 | priv->last_alert_update = jiffies; | |
295 | dev_dbg(&priv->client->dev, "invalidating alert cache\n"); | |
296 | } | |
297 | ||
298 | priv->max_alert |= !!(ret & STTS751_STATUS_TRIPH); | |
299 | priv->min_alert |= !!(ret & STTS751_STATUS_TRIPL); | |
300 | priv->therm_trip = !!(ret & STTS751_STATUS_TRIPT); | |
301 | ||
302 | dev_dbg(&priv->client->dev, "max_alert: %d, min_alert: %d, therm_trip: %d\n", | |
303 | priv->max_alert, priv->min_alert, priv->therm_trip); | |
304 | ||
305 | return 0; | |
306 | } | |
307 | ||
308 | static void stts751_alert(struct i2c_client *client, | |
309 | enum i2c_alert_protocol type, unsigned int data) | |
310 | { | |
311 | int ret; | |
312 | struct stts751_priv *priv = i2c_get_clientdata(client); | |
313 | ||
314 | if (type != I2C_PROTOCOL_SMBUS_ALERT) | |
315 | return; | |
316 | ||
317 | dev_dbg(&client->dev, "alert!"); | |
318 | ||
319 | mutex_lock(&priv->access_lock); | |
320 | ret = stts751_update_alert(priv); | |
321 | if (ret < 0) { | |
322 | /* default to worst case */ | |
323 | priv->max_alert = true; | |
324 | priv->min_alert = true; | |
325 | ||
326 | dev_warn(priv->dev, | |
327 | "Alert received, but can't communicate to the device. Triggering all alarms!"); | |
328 | } | |
329 | ||
330 | if (priv->max_alert) { | |
331 | if (priv->notify_max) | |
332 | dev_notice(priv->dev, "got alert for HIGH temperature"); | |
333 | priv->notify_max = false; | |
334 | ||
335 | /* unblock alert poll */ | |
336 | sysfs_notify(&priv->dev->kobj, NULL, "temp1_max_alarm"); | |
337 | } | |
338 | ||
339 | if (priv->min_alert) { | |
340 | if (priv->notify_min) | |
341 | dev_notice(priv->dev, "got alert for LOW temperature"); | |
342 | priv->notify_min = false; | |
343 | ||
344 | /* unblock alert poll */ | |
345 | sysfs_notify(&priv->dev->kobj, NULL, "temp1_min_alarm"); | |
346 | } | |
347 | ||
348 | if (priv->min_alert || priv->max_alert) | |
349 | kobject_uevent(&priv->dev->kobj, KOBJ_CHANGE); | |
350 | ||
351 | mutex_unlock(&priv->access_lock); | |
352 | } | |
353 | ||
354 | static int stts751_update(struct stts751_priv *priv) | |
355 | { | |
356 | int ret; | |
357 | int cache_time = msecs_to_jiffies(stts751_intervals[priv->interval]); | |
358 | ||
359 | if (time_after(jiffies, priv->last_update + cache_time) || | |
360 | !priv->data_valid) { | |
361 | ret = stts751_update_temp(priv); | |
362 | if (ret) | |
363 | return ret; | |
364 | ||
365 | ret = stts751_update_alert(priv); | |
366 | if (ret) | |
367 | return ret; | |
368 | priv->data_valid = true; | |
369 | priv->last_update = jiffies; | |
370 | } | |
371 | ||
372 | return 0; | |
373 | } | |
374 | ||
ecd52d7b GR |
375 | static ssize_t max_alarm_show(struct device *dev, |
376 | struct device_attribute *attr, char *buf) | |
7f07ec0f | 377 | { |
378 | int ret; | |
379 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
380 | ||
381 | mutex_lock(&priv->access_lock); | |
382 | ret = stts751_update(priv); | |
383 | if (!ret) | |
384 | priv->notify_max = true; | |
385 | mutex_unlock(&priv->access_lock); | |
386 | if (ret < 0) | |
387 | return ret; | |
388 | ||
1f4d4af4 | 389 | return sysfs_emit(buf, "%d\n", priv->max_alert); |
7f07ec0f | 390 | } |
391 | ||
ecd52d7b GR |
392 | static ssize_t min_alarm_show(struct device *dev, |
393 | struct device_attribute *attr, char *buf) | |
7f07ec0f | 394 | { |
395 | int ret; | |
396 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
397 | ||
398 | mutex_lock(&priv->access_lock); | |
399 | ret = stts751_update(priv); | |
400 | if (!ret) | |
401 | priv->notify_min = true; | |
402 | mutex_unlock(&priv->access_lock); | |
403 | if (ret < 0) | |
404 | return ret; | |
405 | ||
1f4d4af4 | 406 | return sysfs_emit(buf, "%d\n", priv->min_alert); |
7f07ec0f | 407 | } |
408 | ||
ecd52d7b | 409 | static ssize_t input_show(struct device *dev, struct device_attribute *attr, |
7f07ec0f | 410 | char *buf) |
411 | { | |
412 | int ret; | |
413 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
414 | ||
415 | mutex_lock(&priv->access_lock); | |
416 | ret = stts751_update(priv); | |
417 | mutex_unlock(&priv->access_lock); | |
418 | if (ret < 0) | |
419 | return ret; | |
420 | ||
1f4d4af4 | 421 | return sysfs_emit(buf, "%d\n", priv->temp); |
7f07ec0f | 422 | } |
423 | ||
ecd52d7b | 424 | static ssize_t therm_show(struct device *dev, struct device_attribute *attr, |
7f07ec0f | 425 | char *buf) |
426 | { | |
427 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
428 | ||
1f4d4af4 | 429 | return sysfs_emit(buf, "%d\n", priv->therm); |
7f07ec0f | 430 | } |
431 | ||
ecd52d7b GR |
432 | static ssize_t therm_store(struct device *dev, struct device_attribute *attr, |
433 | const char *buf, size_t count) | |
7f07ec0f | 434 | { |
435 | int ret; | |
436 | long temp; | |
437 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
438 | ||
439 | if (kstrtol(buf, 10, &temp) < 0) | |
440 | return -EINVAL; | |
441 | ||
442 | /* HW works in range -64C to +127.937C */ | |
443 | temp = clamp_val(temp, -64000, 127937); | |
444 | mutex_lock(&priv->access_lock); | |
445 | ret = stts751_set_temp_reg8(priv, temp, STTS751_REG_TLIM); | |
446 | if (ret) | |
447 | goto exit; | |
448 | ||
449 | dev_dbg(&priv->client->dev, "setting therm %ld", temp); | |
450 | ||
451 | /* | |
452 | * hysteresis reg is relative to therm, so the HW does not need to be | |
453 | * adjusted, we need to update our local copy only. | |
454 | */ | |
455 | priv->hyst = temp - (priv->therm - priv->hyst); | |
456 | priv->therm = temp; | |
457 | ||
458 | exit: | |
459 | mutex_unlock(&priv->access_lock); | |
460 | if (ret) | |
461 | return ret; | |
462 | ||
463 | return count; | |
464 | } | |
465 | ||
ecd52d7b | 466 | static ssize_t hyst_show(struct device *dev, struct device_attribute *attr, |
7f07ec0f | 467 | char *buf) |
468 | { | |
469 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
470 | ||
1f4d4af4 | 471 | return sysfs_emit(buf, "%d\n", priv->hyst); |
7f07ec0f | 472 | } |
473 | ||
ecd52d7b GR |
474 | static ssize_t hyst_store(struct device *dev, struct device_attribute *attr, |
475 | const char *buf, size_t count) | |
7f07ec0f | 476 | { |
477 | int ret; | |
478 | long temp; | |
479 | ||
480 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
481 | ||
482 | if (kstrtol(buf, 10, &temp) < 0) | |
483 | return -EINVAL; | |
484 | ||
485 | mutex_lock(&priv->access_lock); | |
486 | /* HW works in range -64C to +127.937C */ | |
487 | temp = clamp_val(temp, -64000, priv->therm); | |
488 | priv->hyst = temp; | |
489 | dev_dbg(&priv->client->dev, "setting hyst %ld", temp); | |
490 | temp = priv->therm - temp; | |
491 | ret = stts751_set_temp_reg8(priv, temp, STTS751_REG_HYST); | |
492 | mutex_unlock(&priv->access_lock); | |
493 | if (ret) | |
494 | return ret; | |
495 | ||
496 | return count; | |
497 | } | |
498 | ||
ecd52d7b | 499 | static ssize_t therm_trip_show(struct device *dev, |
7f07ec0f | 500 | struct device_attribute *attr, char *buf) |
501 | { | |
502 | int ret; | |
503 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
504 | ||
505 | mutex_lock(&priv->access_lock); | |
506 | ret = stts751_update(priv); | |
507 | mutex_unlock(&priv->access_lock); | |
508 | if (ret < 0) | |
509 | return ret; | |
510 | ||
1f4d4af4 | 511 | return sysfs_emit(buf, "%d\n", priv->therm_trip); |
7f07ec0f | 512 | } |
513 | ||
ecd52d7b | 514 | static ssize_t max_show(struct device *dev, struct device_attribute *attr, |
7f07ec0f | 515 | char *buf) |
516 | { | |
517 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
518 | ||
1f4d4af4 | 519 | return sysfs_emit(buf, "%d\n", priv->event_max); |
7f07ec0f | 520 | } |
521 | ||
ecd52d7b GR |
522 | static ssize_t max_store(struct device *dev, struct device_attribute *attr, |
523 | const char *buf, size_t count) | |
7f07ec0f | 524 | { |
525 | int ret; | |
526 | long temp; | |
527 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
528 | ||
529 | if (kstrtol(buf, 10, &temp) < 0) | |
530 | return -EINVAL; | |
531 | ||
532 | mutex_lock(&priv->access_lock); | |
533 | /* HW works in range -64C to +127.937C */ | |
534 | temp = clamp_val(temp, priv->event_min, 127937); | |
535 | ret = stts751_set_temp_reg16(priv, temp, | |
536 | STTS751_REG_HLIM_H, STTS751_REG_HLIM_L); | |
537 | if (ret) | |
538 | goto exit; | |
539 | ||
540 | dev_dbg(&priv->client->dev, "setting event max %ld", temp); | |
541 | priv->event_max = temp; | |
542 | ret = count; | |
543 | exit: | |
544 | mutex_unlock(&priv->access_lock); | |
545 | return ret; | |
546 | } | |
547 | ||
ecd52d7b | 548 | static ssize_t min_show(struct device *dev, struct device_attribute *attr, |
7f07ec0f | 549 | char *buf) |
550 | { | |
551 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
552 | ||
1f4d4af4 | 553 | return sysfs_emit(buf, "%d\n", priv->event_min); |
7f07ec0f | 554 | } |
555 | ||
ecd52d7b GR |
556 | static ssize_t min_store(struct device *dev, struct device_attribute *attr, |
557 | const char *buf, size_t count) | |
7f07ec0f | 558 | { |
559 | int ret; | |
560 | long temp; | |
561 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
562 | ||
563 | if (kstrtol(buf, 10, &temp) < 0) | |
564 | return -EINVAL; | |
565 | ||
566 | mutex_lock(&priv->access_lock); | |
567 | /* HW works in range -64C to +127.937C */ | |
568 | temp = clamp_val(temp, -64000, priv->event_max); | |
569 | ret = stts751_set_temp_reg16(priv, temp, | |
570 | STTS751_REG_LLIM_H, STTS751_REG_LLIM_L); | |
571 | if (ret) | |
572 | goto exit; | |
573 | ||
574 | dev_dbg(&priv->client->dev, "setting event min %ld", temp); | |
575 | priv->event_min = temp; | |
576 | ret = count; | |
577 | exit: | |
578 | mutex_unlock(&priv->access_lock); | |
579 | return ret; | |
580 | } | |
581 | ||
ecd52d7b GR |
582 | static ssize_t interval_show(struct device *dev, |
583 | struct device_attribute *attr, char *buf) | |
7f07ec0f | 584 | { |
585 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
586 | ||
1f4d4af4 GR |
587 | return sysfs_emit(buf, "%d\n", |
588 | stts751_intervals[priv->interval]); | |
7f07ec0f | 589 | } |
590 | ||
ecd52d7b GR |
591 | static ssize_t interval_store(struct device *dev, |
592 | struct device_attribute *attr, const char *buf, | |
593 | size_t count) | |
7f07ec0f | 594 | { |
595 | unsigned long val; | |
596 | int idx; | |
597 | int ret = count; | |
598 | struct stts751_priv *priv = dev_get_drvdata(dev); | |
599 | ||
600 | if (kstrtoul(buf, 10, &val) < 0) | |
601 | return -EINVAL; | |
602 | ||
603 | idx = find_closest_descending(val, stts751_intervals, | |
604 | ARRAY_SIZE(stts751_intervals)); | |
605 | ||
606 | dev_dbg(&priv->client->dev, "setting interval. req:%lu, idx: %d, val: %d", | |
607 | val, idx, stts751_intervals[idx]); | |
608 | ||
609 | mutex_lock(&priv->access_lock); | |
610 | if (priv->interval == idx) | |
611 | goto exit; | |
612 | ||
613 | /* | |
614 | * In early development stages I've become suspicious about the chip | |
615 | * starting to misbehave if I ever set, even briefly, an invalid | |
616 | * configuration. While I'm not sure this is really needed, be | |
617 | * conservative and set rate/resolution in such an order that avoids | |
618 | * passing through an invalid configuration. | |
619 | */ | |
620 | ||
621 | /* speed up: lower the resolution, then modify convrate */ | |
622 | if (priv->interval < idx) { | |
623 | dev_dbg(&priv->client->dev, "lower resolution, then modify convrate"); | |
624 | priv->interval = idx; | |
625 | ret = stts751_adjust_resolution(priv); | |
626 | if (ret) | |
627 | goto exit; | |
628 | } | |
629 | ||
630 | ret = i2c_smbus_write_byte_data(priv->client, STTS751_REG_RATE, idx); | |
631 | if (ret) | |
632 | goto exit; | |
633 | /* slow down: modify convrate, then raise resolution */ | |
634 | if (priv->interval != idx) { | |
635 | dev_dbg(&priv->client->dev, "modify convrate, then raise resolution"); | |
636 | priv->interval = idx; | |
637 | ret = stts751_adjust_resolution(priv); | |
638 | if (ret) | |
639 | goto exit; | |
640 | } | |
641 | ret = count; | |
642 | exit: | |
643 | mutex_unlock(&priv->access_lock); | |
644 | ||
645 | return ret; | |
646 | } | |
647 | ||
648 | static int stts751_detect(struct i2c_client *new_client, | |
649 | struct i2c_board_info *info) | |
650 | { | |
651 | struct i2c_adapter *adapter = new_client->adapter; | |
652 | const char *name; | |
653 | int tmp; | |
654 | ||
655 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) | |
656 | return -ENODEV; | |
657 | ||
658 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_MAN_ID); | |
659 | if (tmp != ST_MAN_ID) | |
660 | return -ENODEV; | |
661 | ||
662 | /* lower temperaure registers always have bits 0-3 set to zero */ | |
663 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_TEMP_L); | |
664 | if (tmp & 0xf) | |
665 | return -ENODEV; | |
666 | ||
667 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_HLIM_L); | |
668 | if (tmp & 0xf) | |
669 | return -ENODEV; | |
670 | ||
671 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_LLIM_L); | |
672 | if (tmp & 0xf) | |
673 | return -ENODEV; | |
674 | ||
675 | /* smbus timeout register always have bits 0-7 set to zero */ | |
676 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_SMBUS_TO); | |
677 | if (tmp & 0x7f) | |
678 | return -ENODEV; | |
679 | ||
680 | tmp = i2c_smbus_read_byte_data(new_client, STTS751_REG_PROD_ID); | |
681 | ||
682 | switch (tmp) { | |
683 | case STTS751_0_PROD_ID: | |
684 | name = "STTS751-0"; | |
685 | break; | |
686 | case STTS751_1_PROD_ID: | |
687 | name = "STTS751-1"; | |
688 | break; | |
689 | default: | |
690 | return -ENODEV; | |
691 | } | |
692 | dev_dbg(&new_client->dev, "Chip %s detected", name); | |
693 | ||
f2f394db | 694 | strscpy(info->type, stts751_id[0].name, I2C_NAME_SIZE); |
7f07ec0f | 695 | return 0; |
696 | } | |
697 | ||
698 | static int stts751_read_chip_config(struct stts751_priv *priv) | |
699 | { | |
700 | int ret; | |
701 | int tmp; | |
702 | ||
703 | ret = i2c_smbus_read_byte_data(priv->client, STTS751_REG_CONF); | |
704 | if (ret < 0) | |
705 | return ret; | |
706 | priv->config = ret; | |
707 | priv->res = (ret & STTS751_CONF_RES_MASK) >> STTS751_CONF_RES_SHIFT; | |
708 | ||
709 | ret = i2c_smbus_read_byte_data(priv->client, STTS751_REG_RATE); | |
710 | if (ret < 0) | |
711 | return ret; | |
3be6bd69 AV |
712 | if (ret >= ARRAY_SIZE(stts751_intervals)) { |
713 | dev_err(priv->dev, "Unrecognized conversion rate 0x%x\n", ret); | |
714 | return -ENODEV; | |
715 | } | |
7f07ec0f | 716 | priv->interval = ret; |
717 | ||
718 | ret = stts751_read_reg16(priv, &priv->event_max, | |
719 | STTS751_REG_HLIM_H, STTS751_REG_HLIM_L); | |
720 | if (ret) | |
721 | return ret; | |
722 | ||
723 | ret = stts751_read_reg16(priv, &priv->event_min, | |
724 | STTS751_REG_LLIM_H, STTS751_REG_LLIM_L); | |
725 | if (ret) | |
726 | return ret; | |
727 | ||
728 | ret = stts751_read_reg8(priv, &priv->therm, STTS751_REG_TLIM); | |
729 | if (ret) | |
730 | return ret; | |
731 | ||
732 | ret = stts751_read_reg8(priv, &tmp, STTS751_REG_HYST); | |
733 | if (ret) | |
734 | return ret; | |
735 | priv->hyst = priv->therm - tmp; | |
736 | ||
737 | return 0; | |
738 | } | |
739 | ||
ecd52d7b GR |
740 | static SENSOR_DEVICE_ATTR_RO(temp1_input, input, 0); |
741 | static SENSOR_DEVICE_ATTR_RW(temp1_min, min, 0); | |
742 | static SENSOR_DEVICE_ATTR_RW(temp1_max, max, 0); | |
743 | static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, min_alarm, 0); | |
744 | static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, max_alarm, 0); | |
745 | static SENSOR_DEVICE_ATTR_RW(temp1_crit, therm, 0); | |
746 | static SENSOR_DEVICE_ATTR_RW(temp1_crit_hyst, hyst, 0); | |
747 | static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, therm_trip, 0); | |
748 | static SENSOR_DEVICE_ATTR_RW(update_interval, interval, 0); | |
7f07ec0f | 749 | |
750 | static struct attribute *stts751_attrs[] = { | |
751 | &sensor_dev_attr_temp1_input.dev_attr.attr, | |
752 | &sensor_dev_attr_temp1_min.dev_attr.attr, | |
753 | &sensor_dev_attr_temp1_max.dev_attr.attr, | |
754 | &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, | |
755 | &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, | |
756 | &sensor_dev_attr_temp1_crit.dev_attr.attr, | |
757 | &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr, | |
758 | &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, | |
759 | &sensor_dev_attr_update_interval.dev_attr.attr, | |
760 | NULL | |
761 | }; | |
762 | ATTRIBUTE_GROUPS(stts751); | |
763 | ||
67487038 | 764 | static int stts751_probe(struct i2c_client *client) |
7f07ec0f | 765 | { |
766 | struct stts751_priv *priv; | |
767 | int ret; | |
768 | bool smbus_nto; | |
769 | int rev_id; | |
770 | ||
771 | priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL); | |
772 | if (!priv) | |
773 | return -ENOMEM; | |
774 | ||
775 | priv->client = client; | |
776 | priv->notify_max = true; | |
777 | priv->notify_min = true; | |
778 | i2c_set_clientdata(client, priv); | |
779 | mutex_init(&priv->access_lock); | |
780 | ||
781 | if (device_property_present(&client->dev, | |
782 | "smbus-timeout-disable")) { | |
783 | smbus_nto = device_property_read_bool(&client->dev, | |
784 | "smbus-timeout-disable"); | |
785 | ||
786 | ret = i2c_smbus_write_byte_data(client, STTS751_REG_SMBUS_TO, | |
787 | smbus_nto ? 0 : 0x80); | |
788 | if (ret) | |
789 | return ret; | |
790 | } | |
791 | ||
792 | rev_id = i2c_smbus_read_byte_data(client, STTS751_REG_REV_ID); | |
793 | if (rev_id < 0) | |
794 | return -ENODEV; | |
795 | if (rev_id != 0x1) { | |
796 | dev_dbg(&client->dev, "Chip revision 0x%x is untested\n", | |
797 | rev_id); | |
798 | } | |
799 | ||
800 | ret = stts751_read_chip_config(priv); | |
801 | if (ret) | |
802 | return ret; | |
803 | ||
804 | priv->config &= ~(STTS751_CONF_STOP | STTS751_CONF_EVENT_DIS); | |
805 | ret = i2c_smbus_write_byte_data(client, STTS751_REG_CONF, priv->config); | |
806 | if (ret) | |
807 | return ret; | |
808 | ||
809 | priv->dev = devm_hwmon_device_register_with_groups(&client->dev, | |
810 | client->name, priv, | |
811 | stts751_groups); | |
812 | return PTR_ERR_OR_ZERO(priv->dev); | |
813 | } | |
814 | ||
815 | MODULE_DEVICE_TABLE(i2c, stts751_id); | |
816 | ||
817 | static struct i2c_driver stts751_driver = { | |
818 | .class = I2C_CLASS_HWMON, | |
819 | .driver = { | |
820 | .name = DEVNAME, | |
1c1a7b75 | 821 | .of_match_table = of_match_ptr(stts751_of_match), |
7f07ec0f | 822 | }, |
1975d167 | 823 | .probe = stts751_probe, |
7f07ec0f | 824 | .id_table = stts751_id, |
825 | .detect = stts751_detect, | |
826 | .alert = stts751_alert, | |
827 | .address_list = normal_i2c, | |
828 | }; | |
829 | ||
830 | module_i2c_driver(stts751_driver); | |
831 | ||
832 | MODULE_AUTHOR("Andrea Merello <andrea.merello@gmail.com>"); | |
833 | MODULE_DESCRIPTION("STTS751 sensor driver"); | |
834 | MODULE_LICENSE("GPL"); |