aboutsummaryrefslogtreecommitdiff
path: root/drivers/hwmon/w83773g.c
blob: e858093ac806912da9874f35659ef6152c7ba7d1 (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
/*
 * Copyright (C) 2017 IBM Corp.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Driver for the Nuvoton W83773G SMBus temperature sensor IC.
 * Supported models: W83773G
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/of_device.h>
#include <linux/regmap.h>

/* W83773 has 3 channels */
#define W83773_CHANNELS				3

/* The W83773 registers */
#define W83773_CONVERSION_RATE_REG_READ		0x04
#define W83773_CONVERSION_RATE_REG_WRITE	0x0A
#define W83773_MANUFACTURER_ID_REG		0xFE
#define W83773_LOCAL_TEMP			0x00

static const u8 W83773_STATUS[2] = { 0x02, 0x17 };

static const u8 W83773_TEMP_LSB[2] = { 0x10, 0x25 };
static const u8 W83773_TEMP_MSB[2] = { 0x01, 0x24 };

static const u8 W83773_OFFSET_LSB[2] = { 0x12, 0x16 };
static const u8 W83773_OFFSET_MSB[2] = { 0x11, 0x15 };

/* this is the number of sensors in the device */
static const struct i2c_device_id w83773_id[] = {
	{ "w83773g" },
	{ }
};

MODULE_DEVICE_TABLE(i2c, w83773_id);

static const struct of_device_id w83773_of_match[] = {
	{
		.compatible = "nuvoton,w83773g"
	},
	{ },
};
MODULE_DEVICE_TABLE(of, w83773_of_match);

static inline long temp_of_local(s8 reg)
{
	return reg * 1000;
}

static inline long temp_of_remote(s8 hb, u8 lb)
{
	return (hb << 3 | lb >> 5) * 125;
}

static int get_local_temp(struct regmap *regmap, long *val)
{
	unsigned int regval;
	int ret;

	ret = regmap_read(regmap, W83773_LOCAL_TEMP, &regval);
	if (ret < 0)
		return ret;

	*val = temp_of_local(regval);
	return 0;
}

static int get_remote_temp(struct regmap *regmap, int index, long *val)
{
	unsigned int regval_high;
	unsigned int regval_low;
	int ret;

	ret = regmap_read(regmap, W83773_TEMP_MSB[index], &regval_high);
	if (ret < 0)
		return ret;

	ret = regmap_read(regmap, W83773_TEMP_LSB[index], &regval_low);
	if (ret < 0)
		return ret;

	*val = temp_of_remote(regval_high, regval_low);
	return 0;
}

static int get_fault(struct regmap *regmap, int index, long *val)
{
	unsigned int regval;
	int ret;

	ret = regmap_read(regmap, W83773_STATUS[index], &regval);
	if (ret < 0)
		return ret;

	*val = (regval & 0x04) >> 2;
	return 0;
}

static int get_offset(struct regmap *regmap, int index, long *val)
{
	unsigned int regval_high;
	unsigned int regval_low;
	int ret;

	ret = regmap_read(regmap, W83773_OFFSET_MSB[index], &regval_high);
	if (ret < 0)
		return ret;

	ret = regmap_read(regmap, W83773_OFFSET_LSB[index], &regval_low);
	if (ret < 0)
		return ret;

	*val = temp_of_remote(regval_high, regval_low);
	return 0;
}

static int set_offset(struct regmap *regmap, int index, long val)
{
	int ret;
	u8 high_byte;
	u8 low_byte;

	val = clamp_val(val, -127825, 127825);
	/* offset value equals to (high_byte << 3 | low_byte >> 5) * 125 */
	val /= 125;
	high_byte = val >> 3;
	low_byte = (val & 0x07) << 5;

	ret = regmap_write(regmap, W83773_OFFSET_MSB[index], high_byte);
	if (ret < 0)
		return ret;

	return regmap_write(regmap, W83773_OFFSET_LSB[index], low_byte);
}

static int get_update_interval(struct regmap *regmap, long *val)
{
	unsigned int regval;
	int ret;

	ret = regmap_read(regmap, W83773_CONVERSION_RATE_REG_READ, &regval);
	if (ret < 0)
		return ret;

	*val = 16000 >> regval;
	return 0;
}

static int set_update_interval(struct regmap *regmap, long val)
{
	int rate;

	/*
	 * For valid rates, interval can be calculated as
	 *	interval = (1 << (8 - rate)) * 62.5;
	 * Rounded rate is therefore
	 *	rate = 8 - __fls(interval * 8 / (62.5 * 7));
	 * Use clamp_val() to avoid overflows, and to ensure valid input
	 * for __fls.
	 */
	val = clamp_val(val, 62, 16000) * 10;
	rate = 8 - __fls((val * 8 / (625 * 7)));
	return regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, rate);
}

static int w83773_read(struct device *dev, enum hwmon_sensor_types type,
		       u32 attr, int channel, long *val)
{
	struct regmap *regmap = dev_get_drvdata(dev);

	if (type == hwmon_chip) {
		if (attr == hwmon_chip_update_interval)
			return get_update_interval(regmap, val);
		return -EOPNOTSUPP;
	}

	switch (attr) {
	case hwmon_temp_input:
		if (channel == 0)
			return get_local_temp(regmap, val);
		return get_remote_temp(regmap, channel - 1, val);
	case hwmon_temp_fault:
		return get_fault(regmap, channel - 1, val);
	case hwmon_temp_offset:
		return get_offset(regmap, channel - 1, val);
	default:
		return -EOPNOTSUPP;
	}
}

static int w83773_write(struct device *dev, enum hwmon_sensor_types type,
			u32 attr, int channel, long val)
{
	struct regmap *regmap = dev_get_drvdata(dev);

	if (type == hwmon_chip && attr == hwmon_chip_update_interval)
		return set_update_interval(regmap, val);

	if (type == hwmon_temp && attr == hwmon_temp_offset)
		return set_offset(regmap, channel - 1, val);

	return -EOPNOTSUPP;
}

static umode_t w83773_is_visible(const void *data, enum hwmon_sensor_types type,
				 u32 attr, int channel)
{
	switch (type) {
	case hwmon_chip:
		switch (attr) {
		case hwmon_chip_update_interval:
			return 0644;
		}
		break;
	case hwmon_temp:
		switch (attr) {
		case hwmon_temp_input:
		case hwmon_temp_fault:
			return 0444;
		case hwmon_temp_offset:
			return 0644;
		}
		break;
	default:
		break;
	}
	return 0;
}

static const u32 w83773_chip_config[] = {
	HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL,
	0
};

static const struct hwmon_channel_info w83773_chip = {
	.type = hwmon_chip,
	.config = w83773_chip_config,
};

static const u32 w83773_temp_config[] = {
	HWMON_T_INPUT,
	HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_OFFSET,
	HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_OFFSET,
	0
};

static const struct hwmon_channel_info w83773_temp = {
	.type = hwmon_temp,
	.config = w83773_temp_config,
};

static const struct hwmon_channel_info *w83773_info[] = {
	&w83773_chip,
	&w83773_temp,
	NULL
};

static const struct hwmon_ops w83773_ops = {
	.is_visible = w83773_is_visible,
	.read = w83773_read,
	.write = w83773_write,
};

static const struct hwmon_chip_info w83773_chip_info = {
	.ops = &w83773_ops,
	.info = w83773_info,
};

static const struct regmap_config w83773_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
};

static int w83773_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	struct device *dev = &client->dev;
	struct device *hwmon_dev;
	struct regmap *regmap;
	int ret;

	regmap = devm_regmap_init_i2c(client, &w83773_regmap_config);
	if (IS_ERR(regmap)) {
		dev_err(dev, "failed to allocate register map\n");
		return PTR_ERR(regmap);
	}

	/* Set the conversion rate to 2 Hz */
	ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, 0x05);
	if (ret < 0) {
		dev_err(&client->dev, "error writing config rate register\n");
		return ret;
	}

	i2c_set_clientdata(client, regmap);

	hwmon_dev = devm_hwmon_device_register_with_info(dev,
							 client->name,
							 regmap,
							 &w83773_chip_info,
							 NULL);
	return PTR_ERR_OR_ZERO(hwmon_dev);
}

static struct i2c_driver w83773_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
		.name	= "w83773g",
		.of_match_table = of_match_ptr(w83773_of_match),
	},
	.probe = w83773_probe,
	.id_table = w83773_id,
};

module_i2c_driver(w83773_driver);

MODULE_AUTHOR("Lei YU <mine260309@gmail.com>");
MODULE_DESCRIPTION("W83773G temperature sensor driver");
MODULE_LICENSE("GPL");