nilfs2: unbreak compat ioctl
[zen-stable.git] / drivers / hwmon / tmp102.c
blob643aa8c94535b2ec9a1cadc5ce589dd58c860089
1 /* Texas Instruments TMP102 SMBus temperature sensor driver
3 * Copyright (C) 2010 Steven King <sfking@fdwdc.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/slab.h>
23 #include <linux/i2c.h>
24 #include <linux/hwmon.h>
25 #include <linux/hwmon-sysfs.h>
26 #include <linux/err.h>
27 #include <linux/mutex.h>
28 #include <linux/device.h>
30 #define DRIVER_NAME "tmp102"
32 #define TMP102_TEMP_REG 0x00
33 #define TMP102_CONF_REG 0x01
34 /* note: these bit definitions are byte swapped */
35 #define TMP102_CONF_SD 0x0100
36 #define TMP102_CONF_TM 0x0200
37 #define TMP102_CONF_POL 0x0400
38 #define TMP102_CONF_F0 0x0800
39 #define TMP102_CONF_F1 0x1000
40 #define TMP102_CONF_R0 0x2000
41 #define TMP102_CONF_R1 0x4000
42 #define TMP102_CONF_OS 0x8000
43 #define TMP102_CONF_EM 0x0010
44 #define TMP102_CONF_AL 0x0020
45 #define TMP102_CONF_CR0 0x0040
46 #define TMP102_CONF_CR1 0x0080
47 #define TMP102_TLOW_REG 0x02
48 #define TMP102_THIGH_REG 0x03
50 struct tmp102 {
51 struct device *hwmon_dev;
52 struct mutex lock;
53 u16 config_orig;
54 unsigned long last_update;
55 int temp[3];
58 /* convert left adjusted 13-bit TMP102 register value to milliCelsius */
59 static inline int tmp102_reg_to_mC(s16 val)
61 return ((val & ~0x01) * 1000) / 128;
64 /* convert milliCelsius to left adjusted 13-bit TMP102 register value */
65 static inline u16 tmp102_mC_to_reg(int val)
67 return (val * 128) / 1000;
70 static const u8 tmp102_reg[] = {
71 TMP102_TEMP_REG,
72 TMP102_TLOW_REG,
73 TMP102_THIGH_REG,
76 static struct tmp102 *tmp102_update_device(struct i2c_client *client)
78 struct tmp102 *tmp102 = i2c_get_clientdata(client);
80 mutex_lock(&tmp102->lock);
81 if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
82 int i;
83 for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
84 int status = i2c_smbus_read_word_swapped(client,
85 tmp102_reg[i]);
86 if (status > -1)
87 tmp102->temp[i] = tmp102_reg_to_mC(status);
89 tmp102->last_update = jiffies;
91 mutex_unlock(&tmp102->lock);
92 return tmp102;
95 static ssize_t tmp102_show_temp(struct device *dev,
96 struct device_attribute *attr,
97 char *buf)
99 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
100 struct tmp102 *tmp102 = tmp102_update_device(to_i2c_client(dev));
102 return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
105 static ssize_t tmp102_set_temp(struct device *dev,
106 struct device_attribute *attr,
107 const char *buf, size_t count)
109 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
110 struct i2c_client *client = to_i2c_client(dev);
111 struct tmp102 *tmp102 = i2c_get_clientdata(client);
112 long val;
113 int status;
115 if (strict_strtol(buf, 10, &val) < 0)
116 return -EINVAL;
117 val = SENSORS_LIMIT(val, -256000, 255000);
119 mutex_lock(&tmp102->lock);
120 tmp102->temp[sda->index] = val;
121 status = i2c_smbus_write_word_swapped(client, tmp102_reg[sda->index],
122 tmp102_mC_to_reg(val));
123 mutex_unlock(&tmp102->lock);
124 return status ? : count;
127 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
129 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
130 tmp102_set_temp, 1);
132 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
133 tmp102_set_temp, 2);
135 static struct attribute *tmp102_attributes[] = {
136 &sensor_dev_attr_temp1_input.dev_attr.attr,
137 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
138 &sensor_dev_attr_temp1_max.dev_attr.attr,
139 NULL
142 static const struct attribute_group tmp102_attr_group = {
143 .attrs = tmp102_attributes,
146 #define TMP102_CONFIG (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1)
147 #define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL)
149 static int __devinit tmp102_probe(struct i2c_client *client,
150 const struct i2c_device_id *id)
152 struct tmp102 *tmp102;
153 int status;
155 if (!i2c_check_functionality(client->adapter,
156 I2C_FUNC_SMBUS_WORD_DATA)) {
157 dev_err(&client->dev, "adapter doesn't support SMBus word "
158 "transactions\n");
159 return -ENODEV;
162 tmp102 = kzalloc(sizeof(*tmp102), GFP_KERNEL);
163 if (!tmp102) {
164 dev_dbg(&client->dev, "kzalloc failed\n");
165 return -ENOMEM;
167 i2c_set_clientdata(client, tmp102);
169 status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
170 if (status < 0) {
171 dev_err(&client->dev, "error reading config register\n");
172 goto fail_free;
174 tmp102->config_orig = status;
175 status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
176 TMP102_CONFIG);
177 if (status < 0) {
178 dev_err(&client->dev, "error writing config register\n");
179 goto fail_restore_config;
181 status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
182 if (status < 0) {
183 dev_err(&client->dev, "error reading config register\n");
184 goto fail_restore_config;
186 status &= ~TMP102_CONFIG_RD_ONLY;
187 if (status != TMP102_CONFIG) {
188 dev_err(&client->dev, "config settings did not stick\n");
189 status = -ENODEV;
190 goto fail_restore_config;
192 tmp102->last_update = jiffies - HZ;
193 mutex_init(&tmp102->lock);
195 status = sysfs_create_group(&client->dev.kobj, &tmp102_attr_group);
196 if (status) {
197 dev_dbg(&client->dev, "could not create sysfs files\n");
198 goto fail_restore_config;
200 tmp102->hwmon_dev = hwmon_device_register(&client->dev);
201 if (IS_ERR(tmp102->hwmon_dev)) {
202 dev_dbg(&client->dev, "unable to register hwmon device\n");
203 status = PTR_ERR(tmp102->hwmon_dev);
204 goto fail_remove_sysfs;
207 dev_info(&client->dev, "initialized\n");
209 return 0;
211 fail_remove_sysfs:
212 sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
213 fail_restore_config:
214 i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
215 tmp102->config_orig);
216 fail_free:
217 kfree(tmp102);
219 return status;
222 static int __devexit tmp102_remove(struct i2c_client *client)
224 struct tmp102 *tmp102 = i2c_get_clientdata(client);
226 hwmon_device_unregister(tmp102->hwmon_dev);
227 sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
229 /* Stop monitoring if device was stopped originally */
230 if (tmp102->config_orig & TMP102_CONF_SD) {
231 int config;
233 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
234 if (config >= 0)
235 i2c_smbus_write_word_swapped(client, TMP102_CONF_REG,
236 config | TMP102_CONF_SD);
239 kfree(tmp102);
241 return 0;
244 #ifdef CONFIG_PM
245 static int tmp102_suspend(struct device *dev)
247 struct i2c_client *client = to_i2c_client(dev);
248 int config;
250 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
251 if (config < 0)
252 return config;
254 config |= TMP102_CONF_SD;
255 return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
258 static int tmp102_resume(struct device *dev)
260 struct i2c_client *client = to_i2c_client(dev);
261 int config;
263 config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG);
264 if (config < 0)
265 return config;
267 config &= ~TMP102_CONF_SD;
268 return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config);
271 static const struct dev_pm_ops tmp102_dev_pm_ops = {
272 .suspend = tmp102_suspend,
273 .resume = tmp102_resume,
276 #define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
277 #else
278 #define TMP102_DEV_PM_OPS NULL
279 #endif /* CONFIG_PM */
281 static const struct i2c_device_id tmp102_id[] = {
282 { "tmp102", 0 },
285 MODULE_DEVICE_TABLE(i2c, tmp102_id);
287 static struct i2c_driver tmp102_driver = {
288 .driver.name = DRIVER_NAME,
289 .driver.pm = TMP102_DEV_PM_OPS,
290 .probe = tmp102_probe,
291 .remove = __devexit_p(tmp102_remove),
292 .id_table = tmp102_id,
295 static int __init tmp102_init(void)
297 return i2c_add_driver(&tmp102_driver);
299 module_init(tmp102_init);
301 static void __exit tmp102_exit(void)
303 i2c_del_driver(&tmp102_driver);
305 module_exit(tmp102_exit);
307 MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
308 MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
309 MODULE_LICENSE("GPL");