Commit | Line | Data |
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6c633c30 SM |
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 | ||
31 | ||
32 | /* AD7414 registers */ | |
33 | #define AD7414_REG_TEMP 0x00 | |
34 | #define AD7414_REG_CONF 0x01 | |
35 | #define AD7414_REG_T_HIGH 0x02 | |
36 | #define AD7414_REG_T_LOW 0x03 | |
37 | ||
38 | static u8 AD7414_REG_LIMIT[] = { AD7414_REG_T_HIGH, AD7414_REG_T_LOW }; | |
39 | ||
40 | struct ad7414_data { | |
41 | struct device *hwmon_dev; | |
42 | struct mutex lock; /* atomic read data updates */ | |
43 | char valid; /* !=0 if following fields are valid */ | |
44 | unsigned long next_update; /* In jiffies */ | |
45 | s16 temp_input; /* Register values */ | |
46 | s8 temps[ARRAY_SIZE(AD7414_REG_LIMIT)]; | |
47 | }; | |
48 | ||
49 | /* REG: (0.25C/bit, two's complement) << 6 */ | |
50 | static inline int ad7414_temp_from_reg(s16 reg) | |
51 | { | |
52 | /* use integer division instead of equivalent right shift to | |
53 | * guarantee arithmetic shift and preserve the sign | |
54 | */ | |
55 | return ((int)reg / 64) * 250; | |
56 | } | |
57 | ||
58 | static inline int ad7414_read(struct i2c_client *client, u8 reg) | |
59 | { | |
60 | if (reg == AD7414_REG_TEMP) { | |
61 | int value = i2c_smbus_read_word_data(client, reg); | |
62 | return (value < 0) ? value : swab16(value); | |
63 | } else | |
64 | return i2c_smbus_read_byte_data(client, reg); | |
65 | } | |
66 | ||
67 | static inline int ad7414_write(struct i2c_client *client, u8 reg, u8 value) | |
68 | { | |
69 | return i2c_smbus_write_byte_data(client, reg, value); | |
70 | } | |
71 | ||
d130d971 | 72 | static struct ad7414_data *ad7414_update_device(struct device *dev) |
6c633c30 SM |
73 | { |
74 | struct i2c_client *client = to_i2c_client(dev); | |
75 | struct ad7414_data *data = i2c_get_clientdata(client); | |
76 | ||
77 | mutex_lock(&data->lock); | |
78 | ||
79 | if (time_after(jiffies, data->next_update) || !data->valid) { | |
80 | int value, i; | |
81 | ||
82 | dev_dbg(&client->dev, "starting ad7414 update\n"); | |
83 | ||
84 | value = ad7414_read(client, AD7414_REG_TEMP); | |
85 | if (value < 0) | |
86 | dev_dbg(&client->dev, "AD7414_REG_TEMP err %d\n", | |
87 | value); | |
88 | else | |
89 | data->temp_input = value; | |
90 | ||
91 | for (i = 0; i < ARRAY_SIZE(AD7414_REG_LIMIT); ++i) { | |
92 | value = ad7414_read(client, AD7414_REG_LIMIT[i]); | |
93 | if (value < 0) | |
94 | dev_dbg(&client->dev, "AD7414 reg %d err %d\n", | |
95 | AD7414_REG_LIMIT[i], value); | |
96 | else | |
97 | data->temps[i] = value; | |
98 | } | |
99 | ||
100 | data->next_update = jiffies + HZ + HZ / 2; | |
101 | data->valid = 1; | |
102 | } | |
103 | ||
104 | mutex_unlock(&data->lock); | |
105 | ||
106 | return data; | |
107 | } | |
108 | ||
109 | static ssize_t show_temp_input(struct device *dev, | |
110 | struct device_attribute *attr, char *buf) | |
111 | { | |
112 | struct ad7414_data *data = ad7414_update_device(dev); | |
113 | return sprintf(buf, "%d\n", ad7414_temp_from_reg(data->temp_input)); | |
114 | } | |
115 | static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input, NULL, 0); | |
116 | ||
117 | static ssize_t show_max_min(struct device *dev, struct device_attribute *attr, | |
118 | char *buf) | |
119 | { | |
120 | int index = to_sensor_dev_attr(attr)->index; | |
121 | struct ad7414_data *data = ad7414_update_device(dev); | |
122 | return sprintf(buf, "%d\n", data->temps[index] * 1000); | |
123 | } | |
124 | ||
125 | static ssize_t set_max_min(struct device *dev, | |
126 | struct device_attribute *attr, | |
127 | const char *buf, size_t count) | |
128 | { | |
129 | struct i2c_client *client = to_i2c_client(dev); | |
130 | struct ad7414_data *data = i2c_get_clientdata(client); | |
131 | int index = to_sensor_dev_attr(attr)->index; | |
132 | u8 reg = AD7414_REG_LIMIT[index]; | |
133 | long temp = simple_strtol(buf, NULL, 10); | |
134 | ||
135 | temp = SENSORS_LIMIT(temp, -40000, 85000); | |
136 | temp = (temp + (temp < 0 ? -500 : 500)) / 1000; | |
137 | ||
138 | mutex_lock(&data->lock); | |
139 | data->temps[index] = temp; | |
140 | ad7414_write(client, reg, temp); | |
141 | mutex_unlock(&data->lock); | |
142 | return count; | |
143 | } | |
144 | ||
145 | static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, | |
146 | show_max_min, set_max_min, 0); | |
147 | static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, | |
148 | show_max_min, set_max_min, 1); | |
149 | ||
150 | static ssize_t show_alarm(struct device *dev, struct device_attribute *attr, | |
151 | char *buf) | |
152 | { | |
153 | int bitnr = to_sensor_dev_attr(attr)->index; | |
154 | struct ad7414_data *data = ad7414_update_device(dev); | |
155 | int value = (data->temp_input >> bitnr) & 1; | |
156 | return sprintf(buf, "%d\n", value); | |
157 | } | |
158 | ||
159 | static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 3); | |
160 | static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 4); | |
161 | ||
162 | static struct attribute *ad7414_attributes[] = { | |
163 | &sensor_dev_attr_temp1_input.dev_attr.attr, | |
164 | &sensor_dev_attr_temp1_max.dev_attr.attr, | |
165 | &sensor_dev_attr_temp1_min.dev_attr.attr, | |
166 | &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, | |
167 | &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, | |
168 | NULL | |
169 | }; | |
170 | ||
171 | static const struct attribute_group ad7414_group = { | |
172 | .attrs = ad7414_attributes, | |
173 | }; | |
174 | ||
175 | static int ad7414_probe(struct i2c_client *client, | |
176 | const struct i2c_device_id *dev_id) | |
177 | { | |
178 | struct ad7414_data *data; | |
179 | int conf; | |
180 | int err = 0; | |
181 | ||
182 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA | | |
183 | I2C_FUNC_SMBUS_READ_WORD_DATA)) | |
184 | goto exit; | |
185 | ||
186 | data = kzalloc(sizeof(struct ad7414_data), GFP_KERNEL); | |
187 | if (!data) { | |
188 | err = -ENOMEM; | |
189 | goto exit; | |
190 | } | |
191 | ||
192 | i2c_set_clientdata(client, data); | |
193 | mutex_init(&data->lock); | |
194 | ||
195 | dev_info(&client->dev, "chip found\n"); | |
196 | ||
197 | /* Make sure the chip is powered up. */ | |
198 | conf = i2c_smbus_read_byte_data(client, AD7414_REG_CONF); | |
199 | if (conf < 0) | |
200 | dev_warn(&client->dev, | |
201 | "ad7414_probe unable to read config register.\n"); | |
202 | else { | |
203 | conf &= ~(1 << 7); | |
204 | i2c_smbus_write_byte_data(client, AD7414_REG_CONF, conf); | |
205 | } | |
206 | ||
207 | /* Register sysfs hooks */ | |
208 | err = sysfs_create_group(&client->dev.kobj, &ad7414_group); | |
209 | if (err) | |
210 | goto exit_free; | |
211 | ||
212 | data->hwmon_dev = hwmon_device_register(&client->dev); | |
213 | if (IS_ERR(data->hwmon_dev)) { | |
214 | err = PTR_ERR(data->hwmon_dev); | |
215 | goto exit_remove; | |
216 | } | |
217 | ||
218 | return 0; | |
219 | ||
220 | exit_remove: | |
221 | sysfs_remove_group(&client->dev.kobj, &ad7414_group); | |
222 | exit_free: | |
223 | kfree(data); | |
224 | exit: | |
225 | return err; | |
226 | } | |
227 | ||
228 | static int __devexit ad7414_remove(struct i2c_client *client) | |
229 | { | |
230 | struct ad7414_data *data = i2c_get_clientdata(client); | |
231 | ||
232 | hwmon_device_unregister(data->hwmon_dev); | |
233 | sysfs_remove_group(&client->dev.kobj, &ad7414_group); | |
234 | kfree(data); | |
235 | return 0; | |
236 | } | |
237 | ||
238 | static const struct i2c_device_id ad7414_id[] = { | |
239 | { "ad7414", 0 }, | |
240 | {} | |
241 | }; | |
242 | ||
243 | static struct i2c_driver ad7414_driver = { | |
244 | .driver = { | |
245 | .name = "ad7414", | |
246 | }, | |
247 | .probe = ad7414_probe, | |
248 | .remove = __devexit_p(ad7414_remove), | |
249 | .id_table = ad7414_id, | |
250 | }; | |
251 | ||
252 | static int __init ad7414_init(void) | |
253 | { | |
254 | return i2c_add_driver(&ad7414_driver); | |
255 | } | |
256 | module_init(ad7414_init); | |
257 | ||
258 | static void __exit ad7414_exit(void) | |
259 | { | |
260 | i2c_del_driver(&ad7414_driver); | |
261 | } | |
262 | module_exit(ad7414_exit); | |
263 | ||
264 | MODULE_AUTHOR("Stefan Roese <sr at denx.de>, " | |
265 | "Frank Edelhaeuser <frank.edelhaeuser at spansion.com>"); | |
266 | ||
267 | MODULE_DESCRIPTION("AD7414 driver"); | |
268 | MODULE_LICENSE("GPL"); |