summaryrefslogtreecommitdiffstats
path: root/drivers/hwmon/adt7x10.c
blob: 6701920de17f44c1a8c3e3b451007c04929eead2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * adt7x10.c - Part of lm_sensors, Linux kernel modules for hardware
 *	 monitoring
 * This driver handles the ADT7410 and compatible digital temperature sensors.
 * Hartmut Knaack <knaack.h@gmx.de> 2012-07-22
 * based on lm75.c by Frodo Looijaard <frodol@dds.nl>
 * and adt7410.c from iio-staging by Sonic Zhang <sonic.zhang@analog.com>
 */

#include <linux/device.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/hwmon.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/regmap.h>

#include "adt7x10.h"

/*
 * ADT7X10 status
 */
#define ADT7X10_STAT_T_LOW		(1 << 4)
#define ADT7X10_STAT_T_HIGH		(1 << 5)
#define ADT7X10_STAT_T_CRIT		(1 << 6)
#define ADT7X10_STAT_NOT_RDY		(1 << 7)

/*
 * ADT7X10 config
 */
#define ADT7X10_FAULT_QUEUE_MASK	(1 << 0 | 1 << 1)
#define ADT7X10_CT_POLARITY		(1 << 2)
#define ADT7X10_INT_POLARITY		(1 << 3)
#define ADT7X10_EVENT_MODE		(1 << 4)
#define ADT7X10_MODE_MASK		(1 << 5 | 1 << 6)
#define ADT7X10_FULL			(0 << 5 | 0 << 6)
#define ADT7X10_PD			(1 << 5 | 1 << 6)
#define ADT7X10_RESOLUTION		(1 << 7)

/*
 * ADT7X10 masks
 */
#define ADT7X10_T13_VALUE_MASK		0xFFF8
#define ADT7X10_T_HYST_MASK		0xF

/* straight from the datasheet */
#define ADT7X10_TEMP_MIN (-55000)
#define ADT7X10_TEMP_MAX 150000

/* Each client has this additional data */
struct adt7x10_data {
	struct regmap		*regmap;
	struct mutex		update_lock;
	u8			config;
	u8			oldconfig;
	bool			valid;		/* true if temperature valid */
};

enum {
	adt7x10_temperature = 0,
	adt7x10_t_alarm_high,
	adt7x10_t_alarm_low,
	adt7x10_t_crit,
};

static const u8 ADT7X10_REG_TEMP[] = {
	[adt7x10_temperature] = ADT7X10_TEMPERATURE,		/* input */
	[adt7x10_t_alarm_high] = ADT7X10_T_ALARM_HIGH,		/* high */
	[adt7x10_t_alarm_low] = ADT7X10_T_ALARM_LOW,		/* low */
	[adt7x10_t_crit] = ADT7X10_T_CRIT,			/* critical */
};

static irqreturn_t adt7x10_irq_handler(int irq, void *private)
{
	struct device *dev = private;
	struct adt7x10_data *d = dev_get_drvdata(dev);
	unsigned int status;
	int ret;

	ret = regmap_read(d->regmap, ADT7X10_STATUS, &status);
	if (ret < 0)
		return IRQ_HANDLED;

	if (status & ADT7X10_STAT_T_HIGH)
		hwmon_notify_event(dev, hwmon_temp, hwmon_temp_max_alarm, 0);
	if (status & ADT7X10_STAT_T_LOW)
		hwmon_notify_event(dev, hwmon_temp, hwmon_temp_min_alarm, 0);
	if (status & ADT7X10_STAT_T_CRIT)
		hwmon_notify_event(dev, hwmon_temp, hwmon_temp_crit_alarm, 0);

	return IRQ_HANDLED;
}

static int adt7x10_temp_ready(struct regmap *regmap)
{
	unsigned int status;
	int i, ret;

	for (i = 0; i < 6; i++) {
		ret = regmap_read(regmap, ADT7X10_STATUS, &status);
		if (ret < 0)
			return ret;
		if (!(status & ADT7X10_STAT_NOT_RDY))
			return 0;
		msleep(60);
	}
	return -ETIMEDOUT;
}

static s16 ADT7X10_TEMP_TO_REG(long temp)
{
	return DIV_ROUND_CLOSEST(clamp_val(temp, ADT7X10_TEMP_MIN,
					   ADT7X10_TEMP_MAX) * 128, 1000);
}

static int ADT7X10_REG_TO_TEMP(struct adt7x10_data *data, s16 reg)
{
	/* in 13 bit mode, bits 0-2 are status flags - mask them out */
	if (!(data->config & ADT7X10_RESOLUTION))
		reg &= ADT7X10_T13_VALUE_MASK;
	/*
	 * temperature is stored in twos complement format, in steps of
	 * 1/128°C
	 */
	return DIV_ROUND_CLOSEST(reg * 1000, 128);
}

/*-----------------------------------------------------------------------*/

static int adt7x10_temp_read(struct adt7x10_data *data, int index, long *val)
{
	unsigned int regval;
	int ret;

	mutex_lock(&data->update_lock);
	if (index == adt7x10_temperature && !data->valid) {
		/* wait for valid temperature */
		ret = adt7x10_temp_ready(data->regmap);
		if (ret) {
			mutex_unlock(&data->update_lock);
			return ret;
		}
		data->valid = true;
	}
	mutex_unlock(&data->update_lock);

	ret = regmap_read(data->regmap, ADT7X10_REG_TEMP[index], &regval);
	if (ret)
		return ret;

	*val = ADT7X10_REG_TO_TEMP(data, regval);
	return 0;
}

static int adt7x10_temp_write(struct adt7x10_data *data, int index, long temp)
{
	int ret;

	mutex_lock(&data->update_lock);
	ret = regmap_write(data->regmap, ADT7X10_REG_TEMP[index],
			   ADT7X10_TEMP_TO_REG(temp));
	mutex_unlock(&data->update_lock);
	return ret;
}

static int adt7x10_hyst_read(struct adt7x10_data *data, int index, long *val)
{
	int hyst, temp, ret;

	mutex_lock(&data->update_lock);
	ret = regmap_read(data->regmap, ADT7X10_T_HYST, &hyst);
	if (ret) {
		mutex_unlock(&data->update_lock);
		return ret;
	}

	ret = regmap_read(data->regmap, ADT7X10_REG_TEMP[index], &temp);
	mutex_unlock(&data->update_lock);
	if (ret)
		return ret;

	hyst = (hyst & ADT7X10_T_HYST_MASK) * 1000;

	/*
	 * hysteresis is stored as a 4 bit offset in the device, convert it
	 * to an absolute value
	 */
	/* min has positive offset, others have negative */
	if (index == adt7x10_t_alarm_low)
		hyst = -hyst;

	*val = ADT7X10_REG_TO_TEMP(data, temp) - hyst;
	return 0;
}

static int adt7x10_hyst_write(struct adt7x10_data *data, long hyst)
{
	unsigned int regval;
	int limit, ret;

	mutex_lock(&data->update_lock);

	/* convert absolute hysteresis value to a 4 bit delta value */
	ret = regmap_read(data->regmap, ADT7X10_T_ALARM_HIGH, &regval);
	if (ret < 0)
		goto abort;

	limit = ADT7X10_REG_TO_TEMP(data, regval);

	hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX);
	regval = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000), 0,
			   ADT7X10_T_HYST_MASK);
	ret = regmap_write(data->regmap, ADT7X10_T_HYST, regval);
abort:
	mutex_unlock(&data->update_lock);
	return ret;
}

static int adt7x10_alarm_read(struct adt7x10_data *data, int index, long *val)
{
	unsigned int status;
	int ret;

	ret = regmap_read(data->regmap, ADT7X10_STATUS, &status);
	if (ret < 0)
		return ret;

	*val = !!(status & index);

	return 0;
}

static umode_t adt7x10_is_visible(const void *data,
				  enum hwmon_sensor_types type,
				  u32 attr, int channel)
{
	switch (attr) {
	case hwmon_temp_max:
	case hwmon_temp_min:
	case hwmon_temp_crit:
	case hwmon_temp_max_hyst:
		return 0644;
	case hwmon_temp_input:
	case hwmon_temp_min_alarm:
	case hwmon_temp_max_alarm:
	case hwmon_temp_crit_alarm:
	case hwmon_temp_min_hyst:
	case hwmon_temp_crit_hyst:
		return 0444;
	default:
		break;
	}

	return 0;
}

static int adt7x10_read(struct device *dev, enum hwmon_sensor_types type,
			u32 attr, int channel, long *val)
{
	struct adt7x10_data *data = dev_get_drvdata(dev);

	switch (attr) {
	case hwmon_temp_input:
		return adt7x10_temp_read(data, adt7x10_temperature, val);
	case hwmon_temp_max:
		return adt7x10_temp_read(data, adt7x10_t_alarm_high, val);
	case hwmon_temp_min:
		return adt7x10_temp_read(data, adt7x10_t_alarm_low, val);
	case hwmon_temp_crit:
		return adt7x10_temp_read(data, adt7x10_t_crit, val);
	case hwmon_temp_max_hyst:
		return adt7x10_hyst_read(data, adt7x10_t_alarm_high, val);
	case hwmon_temp_min_hyst:
		return adt7x10_hyst_read(data, adt7x10_t_alarm_low, val);
	case hwmon_temp_crit_hyst:
		return adt7x10_hyst_read(data, adt7x10_t_crit, val);
	case hwmon_temp_min_alarm:
		return adt7x10_alarm_read(data, ADT7X10_STAT_T_LOW, val);
	case hwmon_temp_max_alarm:
		return adt7x10_alarm_read(data, ADT7X10_STAT_T_HIGH, val);
	case hwmon_temp_crit_alarm:
		return adt7x10_alarm_read(data, ADT7X10_STAT_T_CRIT, val);
	default:
		return -EOPNOTSUPP;
	}
}

static int adt7x10_write(struct device *dev, enum hwmon_sensor_types type,
			 u32 attr, int channel, long val)
{
	struct adt7x10_data *data = dev_get_drvdata(dev);

	switch (attr) {
	case hwmon_temp_max:
		return adt7x10_temp_write(data, adt7x10_t_alarm_high, val);
	case hwmon_temp_min:
		return adt7x10_temp_write(data, adt7x10_t_alarm_low, val);
	case hwmon_temp_crit:
		return adt7x10_temp_write(data, adt7x10_t_crit, val);
	case hwmon_temp_max_hyst:
		return adt7x10_hyst_write(data, val);
	default:
		return -EOPNOTSUPP;
	}
}

static const struct hwmon_channel_info * const adt7x10_info[] = {
	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN |
			   HWMON_T_CRIT | HWMON_T_MAX_HYST | HWMON_T_MIN_HYST |
			   HWMON_T_CRIT_HYST | HWMON_T_MIN_ALARM |
			   HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM),
	NULL,
};

static const struct hwmon_ops adt7x10_hwmon_ops = {
	.is_visible = adt7x10_is_visible,
	.read = adt7x10_read,
	.write = adt7x10_write,
};

static const struct hwmon_chip_info adt7x10_chip_info = {
	.ops = &adt7x10_hwmon_ops,
	.info = adt7x10_info,
};

static void adt7x10_restore_config(void *private)
{
	struct adt7x10_data *data = private;

	regmap_write(data->regmap, ADT7X10_CONFIG, data->oldconfig);
}

int adt7x10_probe(struct device *dev, const char *name, int irq,
		  struct regmap *regmap)
{
	struct adt7x10_data *data;
	unsigned int config;
	struct device *hdev;
	int ret;

	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->regmap = regmap;

	dev_set_drvdata(dev, data);
	mutex_init(&data->update_lock);

	/* configure as specified */
	ret = regmap_read(regmap, ADT7X10_CONFIG, &config);
	if (ret < 0) {
		dev_dbg(dev, "Can't read config? %d\n", ret);
		return ret;
	}
	data->oldconfig = config;

	/*
	 * Set to 16 bit resolution, continous conversion and comparator mode.
	 */
	data->config = data->oldconfig;
	data->config &= ~(ADT7X10_MODE_MASK | ADT7X10_CT_POLARITY |
			ADT7X10_INT_POLARITY);
	data->config |= ADT7X10_FULL | ADT7X10_RESOLUTION | ADT7X10_EVENT_MODE;

	if (data->config != data->oldconfig) {
		ret = regmap_write(regmap, ADT7X10_CONFIG, data->config);
		if (ret)
			return ret;
		ret = devm_add_action_or_reset(dev, adt7x10_restore_config, data);
		if (ret)
			return ret;
	}
	dev_dbg(dev, "Config %02x\n", data->config);

	hdev = devm_hwmon_device_register_with_info(dev, name, data,
						    &adt7x10_chip_info, NULL);
	if (IS_ERR(hdev))
		return PTR_ERR(hdev);

	if (irq > 0) {
		ret = devm_request_threaded_irq(dev, irq, NULL,
						adt7x10_irq_handler,
						IRQF_TRIGGER_FALLING |
						IRQF_ONESHOT,
						dev_name(dev), hdev);
		if (ret)
			return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(adt7x10_probe);

static int adt7x10_suspend(struct device *dev)
{
	struct adt7x10_data *data = dev_get_drvdata(dev);

	return regmap_write(data->regmap, ADT7X10_CONFIG,
			    data->config | ADT7X10_PD);
}

static int adt7x10_resume(struct device *dev)
{
	struct adt7x10_data *data = dev_get_drvdata(dev);

	return regmap_write(data->regmap, ADT7X10_CONFIG, data->config);
}

EXPORT_SIMPLE_DEV_PM_OPS(adt7x10_dev_pm_ops, adt7x10_suspend, adt7x10_resume);

MODULE_AUTHOR("Hartmut Knaack");
MODULE_DESCRIPTION("ADT7410/ADT7420, ADT7310/ADT7320 common code");
MODULE_LICENSE("GPL");