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1/*
2 * adt7x10.c - Part of lm_sensors, Linux kernel modules for hardware
3 * monitoring
4 * This driver handles the ADT7410 and compatible digital temperature sensors.
5 * Hartmut Knaack <knaack.h@gmx.de> 2012-07-22
6 * based on lm75.c by Frodo Looijaard <frodol@dds.nl>
7 * and adt7410.c from iio-staging by Sonic Zhang <sonic.zhang@analog.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 */
23
24#include <linux/module.h>
25#include <linux/init.h>
26#include <linux/slab.h>
27#include <linux/jiffies.h>
28#include <linux/hwmon.h>
29#include <linux/hwmon-sysfs.h>
30#include <linux/err.h>
31#include <linux/mutex.h>
32#include <linux/delay.h>
33#include <linux/interrupt.h>
34
35#include "adt7x10.h"
36
37/*
38 * ADT7X10 status
39 */
40#define ADT7X10_STAT_T_LOW (1 << 4)
41#define ADT7X10_STAT_T_HIGH (1 << 5)
42#define ADT7X10_STAT_T_CRIT (1 << 6)
43#define ADT7X10_STAT_NOT_RDY (1 << 7)
44
45/*
46 * ADT7X10 config
47 */
48#define ADT7X10_FAULT_QUEUE_MASK (1 << 0 | 1 << 1)
49#define ADT7X10_CT_POLARITY (1 << 2)
50#define ADT7X10_INT_POLARITY (1 << 3)
51#define ADT7X10_EVENT_MODE (1 << 4)
52#define ADT7X10_MODE_MASK (1 << 5 | 1 << 6)
53#define ADT7X10_FULL (0 << 5 | 0 << 6)
54#define ADT7X10_PD (1 << 5 | 1 << 6)
55#define ADT7X10_RESOLUTION (1 << 7)
56
57/*
58 * ADT7X10 masks
59 */
60#define ADT7X10_T13_VALUE_MASK 0xFFF8
61#define ADT7X10_T_HYST_MASK 0xF
62
63/* straight from the datasheet */
64#define ADT7X10_TEMP_MIN (-55000)
65#define ADT7X10_TEMP_MAX 150000
66
67/* Each client has this additional data */
68struct adt7x10_data {
69 const struct adt7x10_ops *ops;
70 const char *name;
71 struct device *hwmon_dev;
72 struct mutex update_lock;
73 u8 config;
74 u8 oldconfig;
75 bool valid; /* true if registers valid */
76 unsigned long last_updated; /* In jiffies */
77 s16 temp[4]; /* Register values,
78 0 = input
79 1 = high
80 2 = low
81 3 = critical */
82 u8 hyst; /* hysteresis offset */
83};
84
85static int adt7x10_read_byte(struct device *dev, u8 reg)
86{
87 struct adt7x10_data *d = dev_get_drvdata(dev);
88 return d->ops->read_byte(dev, reg);
89}
90
91static int adt7x10_write_byte(struct device *dev, u8 reg, u8 data)
92{
93 struct adt7x10_data *d = dev_get_drvdata(dev);
94 return d->ops->write_byte(dev, reg, data);
95}
96
97static int adt7x10_read_word(struct device *dev, u8 reg)
98{
99 struct adt7x10_data *d = dev_get_drvdata(dev);
100 return d->ops->read_word(dev, reg);
101}
102
103static int adt7x10_write_word(struct device *dev, u8 reg, u16 data)
104{
105 struct adt7x10_data *d = dev_get_drvdata(dev);
106 return d->ops->write_word(dev, reg, data);
107}
108
109static const u8 ADT7X10_REG_TEMP[4] = {
110 ADT7X10_TEMPERATURE, /* input */
111 ADT7X10_T_ALARM_HIGH, /* high */
112 ADT7X10_T_ALARM_LOW, /* low */
113 ADT7X10_T_CRIT, /* critical */
114};
115
116static irqreturn_t adt7x10_irq_handler(int irq, void *private)
117{
118 struct device *dev = private;
119 int status;
120
121 status = adt7x10_read_byte(dev, ADT7X10_STATUS);
122 if (status < 0)
123 return IRQ_HANDLED;
124
125 if (status & ADT7X10_STAT_T_HIGH)
126 sysfs_notify(&dev->kobj, NULL, "temp1_max_alarm");
127 if (status & ADT7X10_STAT_T_LOW)
128 sysfs_notify(&dev->kobj, NULL, "temp1_min_alarm");
129 if (status & ADT7X10_STAT_T_CRIT)
130 sysfs_notify(&dev->kobj, NULL, "temp1_crit_alarm");
131
132 return IRQ_HANDLED;
133}
134
135static int adt7x10_temp_ready(struct device *dev)
136{
137 int i, status;
138
139 for (i = 0; i < 6; i++) {
140 status = adt7x10_read_byte(dev, ADT7X10_STATUS);
141 if (status < 0)
142 return status;
143 if (!(status & ADT7X10_STAT_NOT_RDY))
144 return 0;
145 msleep(60);
146 }
147 return -ETIMEDOUT;
148}
149
150static int adt7x10_update_temp(struct device *dev)
151{
152 struct adt7x10_data *data = dev_get_drvdata(dev);
153 int ret = 0;
154
155 mutex_lock(&data->update_lock);
156
157 if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
158 || !data->valid) {
159 int temp;
160
161 dev_dbg(dev, "Starting update\n");
162
163 ret = adt7x10_temp_ready(dev); /* check for new value */
164 if (ret)
165 goto abort;
166
167 temp = adt7x10_read_word(dev, ADT7X10_REG_TEMP[0]);
168 if (temp < 0) {
169 ret = temp;
170 dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
171 ADT7X10_REG_TEMP[0], ret);
172 goto abort;
173 }
174 data->temp[0] = temp;
175 data->last_updated = jiffies;
176 data->valid = true;
177 }
178
179abort:
180 mutex_unlock(&data->update_lock);
181 return ret;
182}
183
184static int adt7x10_fill_cache(struct device *dev)
185{
186 struct adt7x10_data *data = dev_get_drvdata(dev);
187 int ret;
188 int i;
189
190 for (i = 1; i < ARRAY_SIZE(data->temp); i++) {
191 ret = adt7x10_read_word(dev, ADT7X10_REG_TEMP[i]);
192 if (ret < 0) {
193 dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
194 ADT7X10_REG_TEMP[i], ret);
195 return ret;
196 }
197 data->temp[i] = ret;
198 }
199
200 ret = adt7x10_read_byte(dev, ADT7X10_T_HYST);
201 if (ret < 0) {
202 dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
203 ADT7X10_T_HYST, ret);
204 return ret;
205 }
206 data->hyst = ret;
207
208 return 0;
209}
210
211static s16 ADT7X10_TEMP_TO_REG(long temp)
212{
213 return DIV_ROUND_CLOSEST(clamp_val(temp, ADT7X10_TEMP_MIN,
214 ADT7X10_TEMP_MAX) * 128, 1000);
215}
216
217static int ADT7X10_REG_TO_TEMP(struct adt7x10_data *data, s16 reg)
218{
219 /* in 13 bit mode, bits 0-2 are status flags - mask them out */
220 if (!(data->config & ADT7X10_RESOLUTION))
221 reg &= ADT7X10_T13_VALUE_MASK;
222 /*
223 * temperature is stored in twos complement format, in steps of
224 * 1/128°C
225 */
226 return DIV_ROUND_CLOSEST(reg * 1000, 128);
227}
228
229/*-----------------------------------------------------------------------*/
230
231/* sysfs attributes for hwmon */
232
233static ssize_t adt7x10_show_temp(struct device *dev,
234 struct device_attribute *da,
235 char *buf)
236{
237 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
238 struct adt7x10_data *data = dev_get_drvdata(dev);
239
240
241 if (attr->index == 0) {
242 int ret;
243
244 ret = adt7x10_update_temp(dev);
245 if (ret)
246 return ret;
247 }
248
249 return sprintf(buf, "%d\n", ADT7X10_REG_TO_TEMP(data,
250 data->temp[attr->index]));
251}
252
253static ssize_t adt7x10_set_temp(struct device *dev,
254 struct device_attribute *da,
255 const char *buf, size_t count)
256{
257 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
258 struct adt7x10_data *data = dev_get_drvdata(dev);
259 int nr = attr->index;
260 long temp;
261 int ret;
262
263 ret = kstrtol(buf, 10, &temp);
264 if (ret)
265 return ret;
266
267 mutex_lock(&data->update_lock);
268 data->temp[nr] = ADT7X10_TEMP_TO_REG(temp);
269 ret = adt7x10_write_word(dev, ADT7X10_REG_TEMP[nr], data->temp[nr]);
270 if (ret)
271 count = ret;
272 mutex_unlock(&data->update_lock);
273 return count;
274}
275
276static ssize_t adt7x10_show_t_hyst(struct device *dev,
277 struct device_attribute *da,
278 char *buf)
279{
280 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
281 struct adt7x10_data *data = dev_get_drvdata(dev);
282 int nr = attr->index;
283 int hyst;
284
285 hyst = (data->hyst & ADT7X10_T_HYST_MASK) * 1000;
286
287 /*
288 * hysteresis is stored as a 4 bit offset in the device, convert it
289 * to an absolute value
290 */
291 if (nr == 2) /* min has positive offset, others have negative */
292 hyst = -hyst;
293 return sprintf(buf, "%d\n",
294 ADT7X10_REG_TO_TEMP(data, data->temp[nr]) - hyst);
295}
296
297static ssize_t adt7x10_set_t_hyst(struct device *dev,
298 struct device_attribute *da,
299 const char *buf, size_t count)
300{
301 struct adt7x10_data *data = dev_get_drvdata(dev);
302 int limit, ret;
303 long hyst;
304
305 ret = kstrtol(buf, 10, &hyst);
306 if (ret)
307 return ret;
308 /* convert absolute hysteresis value to a 4 bit delta value */
309 limit = ADT7X10_REG_TO_TEMP(data, data->temp[1]);
310 hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX);
311 data->hyst = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000),
312 0, ADT7X10_T_HYST_MASK);
313 ret = adt7x10_write_byte(dev, ADT7X10_T_HYST, data->hyst);
314 if (ret)
315 return ret;
316
317 return count;
318}
319
320static ssize_t adt7x10_show_alarm(struct device *dev,
321 struct device_attribute *da,
322 char *buf)
323{
324 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
325 int ret;
326
327 ret = adt7x10_read_byte(dev, ADT7X10_STATUS);
328 if (ret < 0)
329 return ret;
330
331 return sprintf(buf, "%d\n", !!(ret & attr->index));
332}
333
334static ssize_t name_show(struct device *dev, struct device_attribute *da,
335 char *buf)
336{
337 struct adt7x10_data *data = dev_get_drvdata(dev);
338
339 return sprintf(buf, "%s\n", data->name);
340}
341
342static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adt7x10_show_temp, NULL, 0);
343static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
344 adt7x10_show_temp, adt7x10_set_temp, 1);
345static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
346 adt7x10_show_temp, adt7x10_set_temp, 2);
347static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,
348 adt7x10_show_temp, adt7x10_set_temp, 3);
349static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
350 adt7x10_show_t_hyst, adt7x10_set_t_hyst, 1);
351static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO,
352 adt7x10_show_t_hyst, NULL, 2);
353static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO,
354 adt7x10_show_t_hyst, NULL, 3);
355static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, adt7x10_show_alarm,
356 NULL, ADT7X10_STAT_T_LOW);
357static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adt7x10_show_alarm,
358 NULL, ADT7X10_STAT_T_HIGH);
359static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, adt7x10_show_alarm,
360 NULL, ADT7X10_STAT_T_CRIT);
361static DEVICE_ATTR_RO(name);
362
363static struct attribute *adt7x10_attributes[] = {
364 &sensor_dev_attr_temp1_input.dev_attr.attr,
365 &sensor_dev_attr_temp1_max.dev_attr.attr,
366 &sensor_dev_attr_temp1_min.dev_attr.attr,
367 &sensor_dev_attr_temp1_crit.dev_attr.attr,
368 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
369 &sensor_dev_attr_temp1_min_hyst.dev_attr.attr,
370 &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
371 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
372 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
373 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
374 NULL
375};
376
377static const struct attribute_group adt7x10_group = {
378 .attrs = adt7x10_attributes,
379};
380
381int adt7x10_probe(struct device *dev, const char *name, int irq,
382 const struct adt7x10_ops *ops)
383{
384 struct adt7x10_data *data;
385 int ret;
386
387 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
388 if (!data)
389 return -ENOMEM;
390
391 data->ops = ops;
392 data->name = name;
393
394 dev_set_drvdata(dev, data);
395 mutex_init(&data->update_lock);
396
397 /* configure as specified */
398 ret = adt7x10_read_byte(dev, ADT7X10_CONFIG);
399 if (ret < 0) {
400 dev_dbg(dev, "Can't read config? %d\n", ret);
401 return ret;
402 }
403 data->oldconfig = ret;
404
405 /*
406 * Set to 16 bit resolution, continous conversion and comparator mode.
407 */
408 data->config = data->oldconfig;
409 data->config &= ~(ADT7X10_MODE_MASK | ADT7X10_CT_POLARITY |
410 ADT7X10_INT_POLARITY);
411 data->config |= ADT7X10_FULL | ADT7X10_RESOLUTION | ADT7X10_EVENT_MODE;
412
413 if (data->config != data->oldconfig) {
414 ret = adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config);
415 if (ret)
416 return ret;
417 }
418 dev_dbg(dev, "Config %02x\n", data->config);
419
420 ret = adt7x10_fill_cache(dev);
421 if (ret)
422 goto exit_restore;
423
424 /* Register sysfs hooks */
425 ret = sysfs_create_group(&dev->kobj, &adt7x10_group);
426 if (ret)
427 goto exit_restore;
428
429 /*
430 * The I2C device will already have it's own 'name' attribute, but for
431 * the SPI device we need to register it. name will only be non NULL if
432 * the device doesn't register the 'name' attribute on its own.
433 */
434 if (name) {
435 ret = device_create_file(dev, &dev_attr_name);
436 if (ret)
437 goto exit_remove;
438 }
439
440 data->hwmon_dev = hwmon_device_register(dev);
441 if (IS_ERR(data->hwmon_dev)) {
442 ret = PTR_ERR(data->hwmon_dev);
443 goto exit_remove_name;
444 }
445
446 if (irq > 0) {
447 ret = request_threaded_irq(irq, NULL, adt7x10_irq_handler,
448 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
449 dev_name(dev), dev);
450 if (ret)
451 goto exit_hwmon_device_unregister;
452 }
453
454 return 0;
455
456exit_hwmon_device_unregister:
457 hwmon_device_unregister(data->hwmon_dev);
458exit_remove_name:
459 if (name)
460 device_remove_file(dev, &dev_attr_name);
461exit_remove:
462 sysfs_remove_group(&dev->kobj, &adt7x10_group);
463exit_restore:
464 adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig);
465 return ret;
466}
467EXPORT_SYMBOL_GPL(adt7x10_probe);
468
469int adt7x10_remove(struct device *dev, int irq)
470{
471 struct adt7x10_data *data = dev_get_drvdata(dev);
472
473 if (irq > 0)
474 free_irq(irq, dev);
475
476 hwmon_device_unregister(data->hwmon_dev);
477 if (data->name)
478 device_remove_file(dev, &dev_attr_name);
479 sysfs_remove_group(&dev->kobj, &adt7x10_group);
480 if (data->oldconfig != data->config)
481 adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig);
482 return 0;
483}
484EXPORT_SYMBOL_GPL(adt7x10_remove);
485
486#ifdef CONFIG_PM_SLEEP
487
488static int adt7x10_suspend(struct device *dev)
489{
490 struct adt7x10_data *data = dev_get_drvdata(dev);
491
492 return adt7x10_write_byte(dev, ADT7X10_CONFIG,
493 data->config | ADT7X10_PD);
494}
495
496static int adt7x10_resume(struct device *dev)
497{
498 struct adt7x10_data *data = dev_get_drvdata(dev);
499
500 return adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config);
501}
502
503SIMPLE_DEV_PM_OPS(adt7x10_dev_pm_ops, adt7x10_suspend, adt7x10_resume);
504EXPORT_SYMBOL_GPL(adt7x10_dev_pm_ops);
505
506#endif /* CONFIG_PM_SLEEP */
507
508MODULE_AUTHOR("Hartmut Knaack");
509MODULE_DESCRIPTION("ADT7410/ADT7420, ADT7310/ADT7320 common code");
510MODULE_LICENSE("GPL");