aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/hwmon/adt7411.c
blob: f13c843a2964bbb07728c06363cda065937293bb (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
/*
 *  Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor)
 *
 *  Copyright (C) 2008, 2010 Pengutronix
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  TODO: SPI, support for external temperature sensor
 * 	  use power-down mode for suspend?, interrupt handling?
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/slab.h>

#define ADT7411_REG_INT_TEMP_VDD_LSB		0x03
#define ADT7411_REG_EXT_TEMP_AIN14_LSB		0x04
#define ADT7411_REG_VDD_MSB			0x06
#define ADT7411_REG_INT_TEMP_MSB		0x07
#define ADT7411_REG_EXT_TEMP_AIN1_MSB		0x08

#define ADT7411_REG_CFG1			0x18
#define ADT7411_CFG1_START_MONITOR		(1 << 0)

#define ADT7411_REG_CFG2			0x19
#define ADT7411_CFG2_DISABLE_AVG		(1 << 5)

#define ADT7411_REG_CFG3			0x1a
#define ADT7411_CFG3_ADC_CLK_225		(1 << 0)
#define ADT7411_CFG3_REF_VDD			(1 << 4)

#define ADT7411_REG_DEVICE_ID			0x4d
#define ADT7411_REG_MANUFACTURER_ID		0x4e

#define ADT7411_DEVICE_ID			0x2
#define ADT7411_MANUFACTURER_ID			0x41

static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };

struct adt7411_data {
	struct mutex device_lock;	/* for "atomic" device accesses */
	struct mutex update_lock;
	unsigned long next_update;
	int vref_cached;
	struct device *hwmon_dev;
};

/*
 * When reading a register containing (up to 4) lsb, all associated
 * msb-registers get locked by the hardware. After _one_ of those msb is read,
 * _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
 * is protected here with a mutex, too.
 */
static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
				u8 msb_reg, u8 lsb_shift)
{
	struct adt7411_data *data = i2c_get_clientdata(client);
	int val, tmp;

	mutex_lock(&data->device_lock);

	val = i2c_smbus_read_byte_data(client, lsb_reg);
	if (val < 0)
		goto exit_unlock;

	tmp = (val >> lsb_shift) & 3;
	val = i2c_smbus_read_byte_data(client, msb_reg);

	if (val >= 0)
		val = (val << 2) | tmp;

 exit_unlock:
	mutex_unlock(&data->device_lock);

	return val;
}

static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
				bool flag)
{
	struct adt7411_data *data = i2c_get_clientdata(client);
	int ret, val;

	mutex_lock(&data->device_lock);

	ret = i2c_smbus_read_byte_data(client, reg);
	if (ret < 0)
		goto exit_unlock;

	if (flag)
		val = ret | bit;
	else
		val = ret & ~bit;

	ret = i2c_smbus_write_byte_data(client, reg, val);

 exit_unlock:
	mutex_unlock(&data->device_lock);
	return ret;
}

static ssize_t adt7411_show_vdd(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);
	int ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
			ADT7411_REG_VDD_MSB, 2);

	return ret < 0 ? ret : sprintf(buf, "%u\n", ret * 7000 / 1024);
}

static ssize_t adt7411_show_temp(struct device *dev,
			struct device_attribute *attr, char *buf)
{
	struct i2c_client *client = to_i2c_client(dev);
	int val = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
			ADT7411_REG_INT_TEMP_MSB, 0);

	if (val < 0)
		return val;

	val = val & 0x200 ? val - 0x400 : val; /* 10 bit signed */

	return sprintf(buf, "%d\n", val * 250);
}

static ssize_t adt7411_show_input(struct device *dev,
				  struct device_attribute *attr, char *buf)
{
	int nr = to_sensor_dev_attr(attr)->index;
	struct i2c_client *client = to_i2c_client(dev);
	struct adt7411_data *data = i2c_get_clientdata(client);
	int val;
	u8 lsb_reg, lsb_shift;

	mutex_lock(&data->update_lock);
	if (time_after_eq(jiffies, data->next_update)) {
		val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
		if (val < 0)
			goto exit_unlock;

		if (val & ADT7411_CFG3_REF_VDD) {
			val = adt7411_read_10_bit(client,
					ADT7411_REG_INT_TEMP_VDD_LSB,
					ADT7411_REG_VDD_MSB, 2);
			if (val < 0)
				goto exit_unlock;

			data->vref_cached = val * 7000 / 1024;
		} else {
			data->vref_cached = 2250;
		}

		data->next_update = jiffies + HZ;
	}

	lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
	lsb_shift = 2 * (nr & 0x03);
	val = adt7411_read_10_bit(client, lsb_reg,
			ADT7411_REG_EXT_TEMP_AIN1_MSB + nr, lsb_shift);
	if (val < 0)
		goto exit_unlock;

	val = sprintf(buf, "%u\n", val * data->vref_cached / 1024);
 exit_unlock:
	mutex_unlock(&data->update_lock);
	return val;
}

static ssize_t adt7411_show_bit(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
	struct i2c_client *client = to_i2c_client(dev);
	int ret = i2c_smbus_read_byte_data(client, attr2->index);

	return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
}

static ssize_t adt7411_set_bit(struct device *dev,
			       struct device_attribute *attr, const char *buf,
			       size_t count)
{
	struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
	struct i2c_client *client = to_i2c_client(dev);
	struct adt7411_data *data = i2c_get_clientdata(client);
	int ret;
	unsigned long flag;

	ret = strict_strtoul(buf, 0, &flag);
	if (ret || flag > 1)
		return -EINVAL;

	ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);

	/* force update */
	mutex_lock(&data->update_lock);
	data->next_update = jiffies;
	mutex_unlock(&data->update_lock);

	return ret < 0 ? ret : count;
}

#define ADT7411_BIT_ATTR(__name, __reg, __bit) \
	SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \
	adt7411_set_bit, __bit, __reg)

static DEVICE_ATTR(temp1_input, S_IRUGO, adt7411_show_temp, NULL);
static DEVICE_ATTR(in0_input, S_IRUGO, adt7411_show_vdd, NULL);
static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, adt7411_show_input, NULL, 0);
static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, adt7411_show_input, NULL, 1);
static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, adt7411_show_input, NULL, 2);
static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, adt7411_show_input, NULL, 3);
static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, adt7411_show_input, NULL, 4);
static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, adt7411_show_input, NULL, 5);
static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, adt7411_show_input, NULL, 6);
static SENSOR_DEVICE_ATTR(in8_input, S_IRUGO, adt7411_show_input, NULL, 7);
static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);

static struct attribute *adt7411_attrs[] = {
	&dev_attr_temp1_input.attr,
	&dev_attr_in0_input.attr,
	&sensor_dev_attr_in1_input.dev_attr.attr,
	&sensor_dev_attr_in2_input.dev_attr.attr,
	&sensor_dev_attr_in3_input.dev_attr.attr,
	&sensor_dev_attr_in4_input.dev_attr.attr,
	&sensor_dev_attr_in5_input.dev_attr.attr,
	&sensor_dev_attr_in6_input.dev_attr.attr,
	&sensor_dev_attr_in7_input.dev_attr.attr,
	&sensor_dev_attr_in8_input.dev_attr.attr,
	&sensor_dev_attr_no_average.dev_attr.attr,
	&sensor_dev_attr_fast_sampling.dev_attr.attr,
	&sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
	NULL
};

static const struct attribute_group adt7411_attr_grp = {
	.attrs = adt7411_attrs,
};

static int adt7411_detect(struct i2c_client *client,
			  struct i2c_board_info *info)
{
	int val;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -ENODEV;

	val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID);
	if (val < 0 || val != ADT7411_MANUFACTURER_ID) {
		dev_dbg(&client->dev, "Wrong manufacturer ID. Got %d, "
			"expected %d\n", val, ADT7411_MANUFACTURER_ID);
		return -ENODEV;
	}

	val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
	if (val < 0 || val != ADT7411_DEVICE_ID) {
		dev_dbg(&client->dev, "Wrong device ID. Got %d, "
			"expected %d\n", val, ADT7411_DEVICE_ID);
		return -ENODEV;
	}

	strlcpy(info->type, "adt7411", I2C_NAME_SIZE);

	return 0;
}

static int __devinit adt7411_probe(struct i2c_client *client,
				   const struct i2c_device_id *id)
{
	struct adt7411_data *data;
	int ret;

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

	i2c_set_clientdata(client, data);
	mutex_init(&data->device_lock);
	mutex_init(&data->update_lock);

	ret = adt7411_modify_bit(client, ADT7411_REG_CFG1,
				 ADT7411_CFG1_START_MONITOR, 1);
	if (ret < 0)
		goto exit_free;

	/* force update on first occasion */
	data->next_update = jiffies;

	ret = sysfs_create_group(&client->dev.kobj, &adt7411_attr_grp);
	if (ret)
		goto exit_free;

	data->hwmon_dev = hwmon_device_register(&client->dev);
	if (IS_ERR(data->hwmon_dev)) {
		ret = PTR_ERR(data->hwmon_dev);
		goto exit_remove;
	}

	dev_info(&client->dev, "successfully registered\n");

	return 0;

 exit_remove:
	sysfs_remove_group(&client->dev.kobj, &adt7411_attr_grp);
 exit_free:
	kfree(data);
	return ret;
}

static int __devexit adt7411_remove(struct i2c_client *client)
{
	struct adt7411_data *data = i2c_get_clientdata(client);

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &adt7411_attr_grp);
	kfree(data);
	return 0;
}

static const struct i2c_device_id adt7411_id[] = {
	{ "adt7411", 0 },
	{ }
};

static struct i2c_driver adt7411_driver = {
	.driver		= {
		.name		= "adt7411",
	},
	.probe  = adt7411_probe,
	.remove	= __devexit_p(adt7411_remove),
	.id_table = adt7411_id,
	.detect = adt7411_detect,
	.address_list = normal_i2c,
	.class = I2C_CLASS_HWMON,
};

static int __init sensors_adt7411_init(void)
{
	return i2c_add_driver(&adt7411_driver);
}
module_init(sensors_adt7411_init)

static void __exit sensors_adt7411_exit(void)
{
	i2c_del_driver(&adt7411_driver);
}
module_exit(sensors_adt7411_exit)

MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
	"Wolfram Sang <w.sang@pengutronix.de>");
MODULE_DESCRIPTION("ADT7411 driver");
MODULE_LICENSE("GPL v2");