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1/*
2 * An hwmon driver for the Analog Devices AD7414
3 *
4 * Copyright 2006 Stefan Roese <sr at denx.de>, DENX Software Engineering
5 *
6 * Copyright (c) 2008 PIKA Technologies
7 * Sean MacLennan <smaclennan@pikatech.com>
8 *
9 * Copyright (c) 2008 Spansion Inc.
10 * Frank Edelhaeuser <frank.edelhaeuser at spansion.com>
11 * (converted to "new style" I2C driver model, removed checkpatch.pl warnings)
12 *
13 * Based on ad7418.c
14 * Copyright 2006 Tower Technologies, Alessandro Zummo <a.zummo at towertech.it>
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation; either version 2 of the License, or
19 * (at your option) any later version.
20 */
21
22#include <linux/module.h>
23#include <linux/jiffies.h>
24#include <linux/i2c.h>
25#include <linux/hwmon.h>
26#include <linux/hwmon-sysfs.h>
27#include <linux/err.h>
28#include <linux/mutex.h>
29#include <linux/sysfs.h>
30#include <linux/slab.h>
31
32
33/* AD7414 registers */
34#define AD7414_REG_TEMP 0x00
35#define AD7414_REG_CONF 0x01
36#define AD7414_REG_T_HIGH 0x02
37#define AD7414_REG_T_LOW 0x03
38
39static u8 AD7414_REG_LIMIT[] = { AD7414_REG_T_HIGH, AD7414_REG_T_LOW };
40
41struct ad7414_data {
42 struct device *hwmon_dev;
43 struct mutex lock; /* atomic read data updates */
44 char valid; /* !=0 if following fields are valid */
45 unsigned long next_update; /* In jiffies */
46 s16 temp_input; /* Register values */
47 s8 temps[ARRAY_SIZE(AD7414_REG_LIMIT)];
48};
49
50/* REG: (0.25C/bit, two's complement) << 6 */
51static inline int ad7414_temp_from_reg(s16 reg)
52{
53 /* use integer division instead of equivalent right shift to
54 * guarantee arithmetic shift and preserve the sign
55 */
56 return ((int)reg / 64) * 250;
57}
58
59static inline int ad7414_read(struct i2c_client *client, u8 reg)
60{
61 if (reg == AD7414_REG_TEMP) {
62 int value = i2c_smbus_read_word_data(client, reg);
63 return (value < 0) ? value : swab16(value);
64 } else
65 return i2c_smbus_read_byte_data(client, reg);
66}
67
68static inline int ad7414_write(struct i2c_client *client, u8 reg, u8 value)
69{
70 return i2c_smbus_write_byte_data(client, reg, value);
71}
72
73static struct ad7414_data *ad7414_update_device(struct device *dev)
74{
75 struct i2c_client *client = to_i2c_client(dev);
76 struct ad7414_data *data = i2c_get_clientdata(client);
77
78 mutex_lock(&data->lock);
79
80 if (time_after(jiffies, data->next_update) || !data->valid) {
81 int value, i;
82
83 dev_dbg(&client->dev, "starting ad7414 update\n");
84
85 value = ad7414_read(client, AD7414_REG_TEMP);
86 if (value < 0)
87 dev_dbg(&client->dev, "AD7414_REG_TEMP err %d\n",
88 value);
89 else
90 data->temp_input = value;
91
92 for (i = 0; i < ARRAY_SIZE(AD7414_REG_LIMIT); ++i) {
93 value = ad7414_read(client, AD7414_REG_LIMIT[i]);
94 if (value < 0)
95 dev_dbg(&client->dev, "AD7414 reg %d err %d\n",
96 AD7414_REG_LIMIT[i], value);
97 else
98 data->temps[i] = value;
99 }
100
101 data->next_update = jiffies + HZ + HZ / 2;
102 data->valid = 1;
103 }
104
105 mutex_unlock(&data->lock);
106
107 return data;
108}
109
110static ssize_t show_temp_input(struct device *dev,
111 struct device_attribute *attr, char *buf)
112{
113 struct ad7414_data *data = ad7414_update_device(dev);
114 return sprintf(buf, "%d\n", ad7414_temp_from_reg(data->temp_input));
115}
116static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input, NULL, 0);
117
118static ssize_t show_max_min(struct device *dev, struct device_attribute *attr,
119 char *buf)
120{
121 int index = to_sensor_dev_attr(attr)->index;
122 struct ad7414_data *data = ad7414_update_device(dev);
123 return sprintf(buf, "%d\n", data->temps[index] * 1000);
124}
125
126static ssize_t set_max_min(struct device *dev,
127 struct device_attribute *attr,
128 const char *buf, size_t count)
129{
130 struct i2c_client *client = to_i2c_client(dev);
131 struct ad7414_data *data = i2c_get_clientdata(client);
132 int index = to_sensor_dev_attr(attr)->index;
133 u8 reg = AD7414_REG_LIMIT[index];
134 long temp = simple_strtol(buf, NULL, 10);
135
136 temp = SENSORS_LIMIT(temp, -40000, 85000);
137 temp = (temp + (temp < 0 ? -500 : 500)) / 1000;
138
139 mutex_lock(&data->lock);
140 data->temps[index] = temp;
141 ad7414_write(client, reg, temp);
142 mutex_unlock(&data->lock);
143 return count;
144}
145
146static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
147 show_max_min, set_max_min, 0);
148static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
149 show_max_min, set_max_min, 1);
150
151static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
152 char *buf)
153{
154 int bitnr = to_sensor_dev_attr(attr)->index;
155 struct ad7414_data *data = ad7414_update_device(dev);
156 int value = (data->temp_input >> bitnr) & 1;
157 return sprintf(buf, "%d\n", value);
158}
159
160static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 3);
161static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 4);
162
163static struct attribute *ad7414_attributes[] = {
164 &sensor_dev_attr_temp1_input.dev_attr.attr,
165 &sensor_dev_attr_temp1_max.dev_attr.attr,
166 &sensor_dev_attr_temp1_min.dev_attr.attr,
167 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
168 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
169 NULL
170};
171
172static const struct attribute_group ad7414_group = {
173 .attrs = ad7414_attributes,
174};
175
176static int ad7414_probe(struct i2c_client *client,
177 const struct i2c_device_id *dev_id)
178{
179 struct ad7414_data *data;
180 int conf;
181 int err;
182
183 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
184 I2C_FUNC_SMBUS_READ_WORD_DATA)) {
185 err = -EOPNOTSUPP;
186 goto exit;
187 }
188
189 data = kzalloc(sizeof(struct ad7414_data), GFP_KERNEL);
190 if (!data) {
191 err = -ENOMEM;
192 goto exit;
193 }
194
195 i2c_set_clientdata(client, data);
196 mutex_init(&data->lock);
197
198 dev_info(&client->dev, "chip found\n");
199
200 /* Make sure the chip is powered up. */
201 conf = i2c_smbus_read_byte_data(client, AD7414_REG_CONF);
202 if (conf < 0)
203 dev_warn(&client->dev,
204 "ad7414_probe unable to read config register.\n");
205 else {
206 conf &= ~(1 << 7);
207 i2c_smbus_write_byte_data(client, AD7414_REG_CONF, conf);
208 }
209
210 /* Register sysfs hooks */
211 err = sysfs_create_group(&client->dev.kobj, &ad7414_group);
212 if (err)
213 goto exit_free;
214
215 data->hwmon_dev = hwmon_device_register(&client->dev);
216 if (IS_ERR(data->hwmon_dev)) {
217 err = PTR_ERR(data->hwmon_dev);
218 goto exit_remove;
219 }
220
221 return 0;
222
223exit_remove:
224 sysfs_remove_group(&client->dev.kobj, &ad7414_group);
225exit_free:
226 kfree(data);
227exit:
228 return err;
229}
230
231static int __devexit ad7414_remove(struct i2c_client *client)
232{
233 struct ad7414_data *data = i2c_get_clientdata(client);
234
235 hwmon_device_unregister(data->hwmon_dev);
236 sysfs_remove_group(&client->dev.kobj, &ad7414_group);
237 kfree(data);
238 return 0;
239}
240
241static const struct i2c_device_id ad7414_id[] = {
242 { "ad7414", 0 },
243 {}
244};
245MODULE_DEVICE_TABLE(i2c, ad7414_id);
246
247static struct i2c_driver ad7414_driver = {
248 .driver = {
249 .name = "ad7414",
250 },
251 .probe = ad7414_probe,
252 .remove = __devexit_p(ad7414_remove),
253 .id_table = ad7414_id,
254};
255
256static int __init ad7414_init(void)
257{
258 return i2c_add_driver(&ad7414_driver);
259}
260module_init(ad7414_init);
261
262static void __exit ad7414_exit(void)
263{
264 i2c_del_driver(&ad7414_driver);
265}
266module_exit(ad7414_exit);
267
268MODULE_AUTHOR("Stefan Roese <sr at denx.de>, "
269 "Frank Edelhaeuser <frank.edelhaeuser at spansion.com>");
270
271MODULE_DESCRIPTION("AD7414 driver");
272MODULE_LICENSE("GPL");
1/*
2 * An hwmon driver for the Analog Devices AD7414
3 *
4 * Copyright 2006 Stefan Roese <sr at denx.de>, DENX Software Engineering
5 *
6 * Copyright (c) 2008 PIKA Technologies
7 * Sean MacLennan <smaclennan@pikatech.com>
8 *
9 * Copyright (c) 2008 Spansion Inc.
10 * Frank Edelhaeuser <frank.edelhaeuser at spansion.com>
11 * (converted to "new style" I2C driver model, removed checkpatch.pl warnings)
12 *
13 * Based on ad7418.c
14 * Copyright 2006 Tower Technologies, Alessandro Zummo <a.zummo at towertech.it>
15 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation; either version 2 of the License, or
19 * (at your option) any later version.
20 */
21
22#include <linux/module.h>
23#include <linux/jiffies.h>
24#include <linux/i2c.h>
25#include <linux/hwmon.h>
26#include <linux/hwmon-sysfs.h>
27#include <linux/err.h>
28#include <linux/mutex.h>
29#include <linux/sysfs.h>
30#include <linux/slab.h>
31
32
33/* AD7414 registers */
34#define AD7414_REG_TEMP 0x00
35#define AD7414_REG_CONF 0x01
36#define AD7414_REG_T_HIGH 0x02
37#define AD7414_REG_T_LOW 0x03
38
39static u8 AD7414_REG_LIMIT[] = { AD7414_REG_T_HIGH, AD7414_REG_T_LOW };
40
41struct ad7414_data {
42 struct device *hwmon_dev;
43 struct mutex lock; /* atomic read data updates */
44 char valid; /* !=0 if following fields are valid */
45 unsigned long next_update; /* In jiffies */
46 s16 temp_input; /* Register values */
47 s8 temps[ARRAY_SIZE(AD7414_REG_LIMIT)];
48};
49
50/* REG: (0.25C/bit, two's complement) << 6 */
51static inline int ad7414_temp_from_reg(s16 reg)
52{
53 /*
54 * use integer division instead of equivalent right shift to
55 * guarantee arithmetic shift and preserve the sign
56 */
57 return ((int)reg / 64) * 250;
58}
59
60static inline int ad7414_read(struct i2c_client *client, u8 reg)
61{
62 if (reg == AD7414_REG_TEMP)
63 return i2c_smbus_read_word_swapped(client, reg);
64 else
65 return i2c_smbus_read_byte_data(client, reg);
66}
67
68static inline int ad7414_write(struct i2c_client *client, u8 reg, u8 value)
69{
70 return i2c_smbus_write_byte_data(client, reg, value);
71}
72
73static struct ad7414_data *ad7414_update_device(struct device *dev)
74{
75 struct i2c_client *client = to_i2c_client(dev);
76 struct ad7414_data *data = i2c_get_clientdata(client);
77
78 mutex_lock(&data->lock);
79
80 if (time_after(jiffies, data->next_update) || !data->valid) {
81 int value, i;
82
83 dev_dbg(&client->dev, "starting ad7414 update\n");
84
85 value = ad7414_read(client, AD7414_REG_TEMP);
86 if (value < 0)
87 dev_dbg(&client->dev, "AD7414_REG_TEMP err %d\n",
88 value);
89 else
90 data->temp_input = value;
91
92 for (i = 0; i < ARRAY_SIZE(AD7414_REG_LIMIT); ++i) {
93 value = ad7414_read(client, AD7414_REG_LIMIT[i]);
94 if (value < 0)
95 dev_dbg(&client->dev, "AD7414 reg %d err %d\n",
96 AD7414_REG_LIMIT[i], value);
97 else
98 data->temps[i] = value;
99 }
100
101 data->next_update = jiffies + HZ + HZ / 2;
102 data->valid = 1;
103 }
104
105 mutex_unlock(&data->lock);
106
107 return data;
108}
109
110static ssize_t show_temp_input(struct device *dev,
111 struct device_attribute *attr, char *buf)
112{
113 struct ad7414_data *data = ad7414_update_device(dev);
114 return sprintf(buf, "%d\n", ad7414_temp_from_reg(data->temp_input));
115}
116static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input, NULL, 0);
117
118static ssize_t show_max_min(struct device *dev, struct device_attribute *attr,
119 char *buf)
120{
121 int index = to_sensor_dev_attr(attr)->index;
122 struct ad7414_data *data = ad7414_update_device(dev);
123 return sprintf(buf, "%d\n", data->temps[index] * 1000);
124}
125
126static ssize_t set_max_min(struct device *dev,
127 struct device_attribute *attr,
128 const char *buf, size_t count)
129{
130 struct i2c_client *client = to_i2c_client(dev);
131 struct ad7414_data *data = i2c_get_clientdata(client);
132 int index = to_sensor_dev_attr(attr)->index;
133 u8 reg = AD7414_REG_LIMIT[index];
134 long temp;
135 int ret = kstrtol(buf, 10, &temp);
136
137 if (ret < 0)
138 return ret;
139
140 temp = SENSORS_LIMIT(temp, -40000, 85000);
141 temp = (temp + (temp < 0 ? -500 : 500)) / 1000;
142
143 mutex_lock(&data->lock);
144 data->temps[index] = temp;
145 ad7414_write(client, reg, temp);
146 mutex_unlock(&data->lock);
147 return count;
148}
149
150static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
151 show_max_min, set_max_min, 0);
152static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
153 show_max_min, set_max_min, 1);
154
155static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
156 char *buf)
157{
158 int bitnr = to_sensor_dev_attr(attr)->index;
159 struct ad7414_data *data = ad7414_update_device(dev);
160 int value = (data->temp_input >> bitnr) & 1;
161 return sprintf(buf, "%d\n", value);
162}
163
164static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 3);
165static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 4);
166
167static struct attribute *ad7414_attributes[] = {
168 &sensor_dev_attr_temp1_input.dev_attr.attr,
169 &sensor_dev_attr_temp1_max.dev_attr.attr,
170 &sensor_dev_attr_temp1_min.dev_attr.attr,
171 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
172 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
173 NULL
174};
175
176static const struct attribute_group ad7414_group = {
177 .attrs = ad7414_attributes,
178};
179
180static int ad7414_probe(struct i2c_client *client,
181 const struct i2c_device_id *dev_id)
182{
183 struct ad7414_data *data;
184 int conf;
185 int err;
186
187 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
188 I2C_FUNC_SMBUS_READ_WORD_DATA)) {
189 err = -EOPNOTSUPP;
190 goto exit;
191 }
192
193 data = kzalloc(sizeof(struct ad7414_data), GFP_KERNEL);
194 if (!data) {
195 err = -ENOMEM;
196 goto exit;
197 }
198
199 i2c_set_clientdata(client, data);
200 mutex_init(&data->lock);
201
202 dev_info(&client->dev, "chip found\n");
203
204 /* Make sure the chip is powered up. */
205 conf = i2c_smbus_read_byte_data(client, AD7414_REG_CONF);
206 if (conf < 0)
207 dev_warn(&client->dev,
208 "ad7414_probe unable to read config register.\n");
209 else {
210 conf &= ~(1 << 7);
211 i2c_smbus_write_byte_data(client, AD7414_REG_CONF, conf);
212 }
213
214 /* Register sysfs hooks */
215 err = sysfs_create_group(&client->dev.kobj, &ad7414_group);
216 if (err)
217 goto exit_free;
218
219 data->hwmon_dev = hwmon_device_register(&client->dev);
220 if (IS_ERR(data->hwmon_dev)) {
221 err = PTR_ERR(data->hwmon_dev);
222 goto exit_remove;
223 }
224
225 return 0;
226
227exit_remove:
228 sysfs_remove_group(&client->dev.kobj, &ad7414_group);
229exit_free:
230 kfree(data);
231exit:
232 return err;
233}
234
235static int __devexit ad7414_remove(struct i2c_client *client)
236{
237 struct ad7414_data *data = i2c_get_clientdata(client);
238
239 hwmon_device_unregister(data->hwmon_dev);
240 sysfs_remove_group(&client->dev.kobj, &ad7414_group);
241 kfree(data);
242 return 0;
243}
244
245static const struct i2c_device_id ad7414_id[] = {
246 { "ad7414", 0 },
247 {}
248};
249MODULE_DEVICE_TABLE(i2c, ad7414_id);
250
251static struct i2c_driver ad7414_driver = {
252 .driver = {
253 .name = "ad7414",
254 },
255 .probe = ad7414_probe,
256 .remove = __devexit_p(ad7414_remove),
257 .id_table = ad7414_id,
258};
259
260module_i2c_driver(ad7414_driver);
261
262MODULE_AUTHOR("Stefan Roese <sr at denx.de>, "
263 "Frank Edelhaeuser <frank.edelhaeuser at spansion.com>");
264
265MODULE_DESCRIPTION("AD7414 driver");
266MODULE_LICENSE("GPL");