aboutsummaryrefslogtreecommitdiff
path: root/drivers/hwmon/ad7418.c
blob: a50a6bef16c4b526a03dc176da76216dc9c4d2af (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
/*
 * An hwmon driver for the Analog Devices AD7416/17/18
 * Copyright (C) 2006-07 Tower Technologies
 *
 * Author: Alessandro Zummo <a.zummo@towertech.it>
 *
 * Based on lm75.c
 * Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
 *
 * 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 - version 2.
 */

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

#include "lm75.h"

#define DRV_VERSION "0.4"

enum chips { ad7416, ad7417, ad7418 };

/* AD7418 registers */
#define AD7418_REG_TEMP_IN	0x00
#define AD7418_REG_CONF		0x01
#define AD7418_REG_TEMP_HYST	0x02
#define AD7418_REG_TEMP_OS	0x03
#define AD7418_REG_ADC		0x04
#define AD7418_REG_CONF2	0x05

#define AD7418_REG_ADC_CH(x)	((x) << 5)
#define AD7418_CH_TEMP		AD7418_REG_ADC_CH(0)

static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN,
					AD7418_REG_TEMP_HYST,
					AD7418_REG_TEMP_OS };

struct ad7418_data {
	struct device		*hwmon_dev;
	struct attribute_group	attrs;
	enum chips		type;
	struct mutex		lock;
	int			adc_max;	/* number of ADC channels */
	char			valid;
	unsigned long		last_updated;	/* In jiffies */
	s16			temp[3];	/* Register values */
	u16			in[4];
};

static int ad7418_probe(struct i2c_client *client,
			const struct i2c_device_id *id);
static int ad7418_remove(struct i2c_client *client);

static const struct i2c_device_id ad7418_id[] = {
	{ "ad7416", ad7416 },
	{ "ad7417", ad7417 },
	{ "ad7418", ad7418 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, ad7418_id);

static struct i2c_driver ad7418_driver = {
	.driver = {
		.name	= "ad7418",
	},
	.probe		= ad7418_probe,
	.remove		= ad7418_remove,
	.id_table	= ad7418_id,
};

static void ad7418_init_client(struct i2c_client *client)
{
	struct ad7418_data *data = i2c_get_clientdata(client);

	int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
	if (reg < 0) {
		dev_err(&client->dev, "cannot read configuration register\n");
	} else {
		dev_info(&client->dev, "configuring for mode 1\n");
		i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe);

		if (data->type == ad7417 || data->type == ad7418)
			i2c_smbus_write_byte_data(client,
						AD7418_REG_CONF2, 0x00);
	}
}

static struct ad7418_data *ad7418_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct ad7418_data *data = i2c_get_clientdata(client);

	mutex_lock(&data->lock);

	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
		|| !data->valid) {
		u8 cfg;
		int i, ch;

		/* read config register and clear channel bits */
		cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
		cfg &= 0x1F;

		i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
						cfg | AD7418_CH_TEMP);
		udelay(30);

		for (i = 0; i < 3; i++) {
			data->temp[i] =
				i2c_smbus_read_word_swapped(client,
						AD7418_REG_TEMP[i]);
		}

		for (i = 0, ch = 4; i < data->adc_max; i++, ch--) {
			i2c_smbus_write_byte_data(client,
					AD7418_REG_CONF,
					cfg | AD7418_REG_ADC_CH(ch));

			udelay(15);
			data->in[data->adc_max - 1 - i] =
				i2c_smbus_read_word_swapped(client,
						AD7418_REG_ADC);
		}

		/* restore old configuration value */
		i2c_smbus_write_word_swapped(client, AD7418_REG_CONF, cfg);

		data->last_updated = jiffies;
		data->valid = 1;
	}

	mutex_unlock(&data->lock);

	return data;
}

static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
			char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct ad7418_data *data = ad7418_update_device(dev);
	return sprintf(buf, "%d\n",
		LM75_TEMP_FROM_REG(data->temp[attr->index]));
}

static ssize_t show_adc(struct device *dev, struct device_attribute *devattr,
			char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct ad7418_data *data = ad7418_update_device(dev);

	return sprintf(buf, "%d\n",
		((data->in[attr->index] >> 6) * 2500 + 512) / 1024);
}

static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
			const char *buf, size_t count)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	struct i2c_client *client = to_i2c_client(dev);
	struct ad7418_data *data = i2c_get_clientdata(client);
	long temp;
	int ret = kstrtol(buf, 10, &temp);

	if (ret < 0)
		return ret;

	mutex_lock(&data->lock);
	data->temp[attr->index] = LM75_TEMP_TO_REG(temp);
	i2c_smbus_write_word_swapped(client,
				     AD7418_REG_TEMP[attr->index],
				     data->temp[attr->index]);
	mutex_unlock(&data->lock);
	return count;
}

static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
				show_temp, set_temp, 1);
static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
				show_temp, set_temp, 2);

static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_adc, NULL, 0);
static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_adc, NULL, 1);
static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_adc, NULL, 2);
static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_adc, NULL, 3);

static struct attribute *ad7416_attributes[] = {
	&sensor_dev_attr_temp1_max.dev_attr.attr,
	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	NULL
};

static struct attribute *ad7417_attributes[] = {
	&sensor_dev_attr_temp1_max.dev_attr.attr,
	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
	&sensor_dev_attr_temp1_input.dev_attr.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,
	NULL
};

static struct attribute *ad7418_attributes[] = {
	&sensor_dev_attr_temp1_max.dev_attr.attr,
	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	&sensor_dev_attr_in1_input.dev_attr.attr,
	NULL
};

static int ad7418_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct i2c_adapter *adapter = client->adapter;
	struct ad7418_data *data;
	int err;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
					I2C_FUNC_SMBUS_WORD_DATA)) {
		err = -EOPNOTSUPP;
		goto exit;
	}

	data = kzalloc(sizeof(struct ad7418_data), GFP_KERNEL);
	if (!data) {
		err = -ENOMEM;
		goto exit;
	}

	i2c_set_clientdata(client, data);

	mutex_init(&data->lock);
	data->type = id->driver_data;

	switch (data->type) {
	case ad7416:
		data->adc_max = 0;
		data->attrs.attrs = ad7416_attributes;
		break;

	case ad7417:
		data->adc_max = 4;
		data->attrs.attrs = ad7417_attributes;
		break;

	case ad7418:
		data->adc_max = 1;
		data->attrs.attrs = ad7418_attributes;
		break;
	}

	dev_info(&client->dev, "%s chip found\n", client->name);

	/* Initialize the AD7418 chip */
	ad7418_init_client(client);

	/* Register sysfs hooks */
	err = sysfs_create_group(&client->dev.kobj, &data->attrs);
	if (err)
		goto exit_free;

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

	return 0;

exit_remove:
	sysfs_remove_group(&client->dev.kobj, &data->attrs);
exit_free:
	kfree(data);
exit:
	return err;
}

static int ad7418_remove(struct i2c_client *client)
{
	struct ad7418_data *data = i2c_get_clientdata(client);
	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &data->attrs);
	kfree(data);
	return 0;
}

module_i2c_driver(ad7418_driver);

MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("AD7416/17/18 driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);