cifs: turn read_from_socket into a wrapper around a vectorized version
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / hwmon / tmp102.c
blob5bd19496880146cf74630d85ace282e8d7986314
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 /* SMBus specifies low byte first, but the TMP102 returns high byte first,
59 * so we have to swab16 the values */
60 static inline int tmp102_read_reg(struct i2c_client *client, u8 reg)
62 int result = i2c_smbus_read_word_data(client, reg);
63 return result < 0 ? result : swab16(result);
66 static inline int tmp102_write_reg(struct i2c_client *client, u8 reg, u16 val)
68 return i2c_smbus_write_word_data(client, reg, swab16(val));
71 /* convert left adjusted 13-bit TMP102 register value to milliCelsius */
72 static inline int tmp102_reg_to_mC(s16 val)
74 return ((val & ~0x01) * 1000) / 128;
77 /* convert milliCelsius to left adjusted 13-bit TMP102 register value */
78 static inline u16 tmp102_mC_to_reg(int val)
80 return (val * 128) / 1000;
83 static const u8 tmp102_reg[] = {
84 TMP102_TEMP_REG,
85 TMP102_TLOW_REG,
86 TMP102_THIGH_REG,
89 static struct tmp102 *tmp102_update_device(struct i2c_client *client)
91 struct tmp102 *tmp102 = i2c_get_clientdata(client);
93 mutex_lock(&tmp102->lock);
94 if (time_after(jiffies, tmp102->last_update + HZ / 3)) {
95 int i;
96 for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) {
97 int status = tmp102_read_reg(client, tmp102_reg[i]);
98 if (status > -1)
99 tmp102->temp[i] = tmp102_reg_to_mC(status);
101 tmp102->last_update = jiffies;
103 mutex_unlock(&tmp102->lock);
104 return tmp102;
107 static ssize_t tmp102_show_temp(struct device *dev,
108 struct device_attribute *attr,
109 char *buf)
111 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
112 struct tmp102 *tmp102 = tmp102_update_device(to_i2c_client(dev));
114 return sprintf(buf, "%d\n", tmp102->temp[sda->index]);
117 static ssize_t tmp102_set_temp(struct device *dev,
118 struct device_attribute *attr,
119 const char *buf, size_t count)
121 struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
122 struct i2c_client *client = to_i2c_client(dev);
123 struct tmp102 *tmp102 = i2c_get_clientdata(client);
124 long val;
125 int status;
127 if (strict_strtol(buf, 10, &val) < 0)
128 return -EINVAL;
129 val = SENSORS_LIMIT(val, -256000, 255000);
131 mutex_lock(&tmp102->lock);
132 tmp102->temp[sda->index] = val;
133 status = tmp102_write_reg(client, tmp102_reg[sda->index],
134 tmp102_mC_to_reg(val));
135 mutex_unlock(&tmp102->lock);
136 return status ? : count;
139 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0);
141 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp,
142 tmp102_set_temp, 1);
144 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp,
145 tmp102_set_temp, 2);
147 static struct attribute *tmp102_attributes[] = {
148 &sensor_dev_attr_temp1_input.dev_attr.attr,
149 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
150 &sensor_dev_attr_temp1_max.dev_attr.attr,
151 NULL
154 static const struct attribute_group tmp102_attr_group = {
155 .attrs = tmp102_attributes,
158 #define TMP102_CONFIG (TMP102_CONF_TM | TMP102_CONF_EM | TMP102_CONF_CR1)
159 #define TMP102_CONFIG_RD_ONLY (TMP102_CONF_R0 | TMP102_CONF_R1 | TMP102_CONF_AL)
161 static int __devinit tmp102_probe(struct i2c_client *client,
162 const struct i2c_device_id *id)
164 struct tmp102 *tmp102;
165 int status;
167 if (!i2c_check_functionality(client->adapter,
168 I2C_FUNC_SMBUS_WORD_DATA)) {
169 dev_err(&client->dev, "adapter doesn't support SMBus word "
170 "transactions\n");
171 return -ENODEV;
174 tmp102 = kzalloc(sizeof(*tmp102), GFP_KERNEL);
175 if (!tmp102) {
176 dev_dbg(&client->dev, "kzalloc failed\n");
177 return -ENOMEM;
179 i2c_set_clientdata(client, tmp102);
181 status = tmp102_read_reg(client, TMP102_CONF_REG);
182 if (status < 0) {
183 dev_err(&client->dev, "error reading config register\n");
184 goto fail_free;
186 tmp102->config_orig = status;
187 status = tmp102_write_reg(client, TMP102_CONF_REG, TMP102_CONFIG);
188 if (status < 0) {
189 dev_err(&client->dev, "error writing config register\n");
190 goto fail_restore_config;
192 status = tmp102_read_reg(client, TMP102_CONF_REG);
193 if (status < 0) {
194 dev_err(&client->dev, "error reading config register\n");
195 goto fail_restore_config;
197 status &= ~TMP102_CONFIG_RD_ONLY;
198 if (status != TMP102_CONFIG) {
199 dev_err(&client->dev, "config settings did not stick\n");
200 status = -ENODEV;
201 goto fail_restore_config;
203 tmp102->last_update = jiffies - HZ;
204 mutex_init(&tmp102->lock);
206 status = sysfs_create_group(&client->dev.kobj, &tmp102_attr_group);
207 if (status) {
208 dev_dbg(&client->dev, "could not create sysfs files\n");
209 goto fail_restore_config;
211 tmp102->hwmon_dev = hwmon_device_register(&client->dev);
212 if (IS_ERR(tmp102->hwmon_dev)) {
213 dev_dbg(&client->dev, "unable to register hwmon device\n");
214 status = PTR_ERR(tmp102->hwmon_dev);
215 goto fail_remove_sysfs;
218 dev_info(&client->dev, "initialized\n");
220 return 0;
222 fail_remove_sysfs:
223 sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
224 fail_restore_config:
225 tmp102_write_reg(client, TMP102_CONF_REG, tmp102->config_orig);
226 fail_free:
227 kfree(tmp102);
229 return status;
232 static int __devexit tmp102_remove(struct i2c_client *client)
234 struct tmp102 *tmp102 = i2c_get_clientdata(client);
236 hwmon_device_unregister(tmp102->hwmon_dev);
237 sysfs_remove_group(&client->dev.kobj, &tmp102_attr_group);
239 /* Stop monitoring if device was stopped originally */
240 if (tmp102->config_orig & TMP102_CONF_SD) {
241 int config;
243 config = tmp102_read_reg(client, TMP102_CONF_REG);
244 if (config >= 0)
245 tmp102_write_reg(client, TMP102_CONF_REG,
246 config | TMP102_CONF_SD);
249 kfree(tmp102);
251 return 0;
254 #ifdef CONFIG_PM
255 static int tmp102_suspend(struct device *dev)
257 struct i2c_client *client = to_i2c_client(dev);
258 int config;
260 config = tmp102_read_reg(client, TMP102_CONF_REG);
261 if (config < 0)
262 return config;
264 config |= TMP102_CONF_SD;
265 return tmp102_write_reg(client, TMP102_CONF_REG, config);
268 static int tmp102_resume(struct device *dev)
270 struct i2c_client *client = to_i2c_client(dev);
271 int config;
273 config = tmp102_read_reg(client, TMP102_CONF_REG);
274 if (config < 0)
275 return config;
277 config &= ~TMP102_CONF_SD;
278 return tmp102_write_reg(client, TMP102_CONF_REG, config);
281 static const struct dev_pm_ops tmp102_dev_pm_ops = {
282 .suspend = tmp102_suspend,
283 .resume = tmp102_resume,
286 #define TMP102_DEV_PM_OPS (&tmp102_dev_pm_ops)
287 #else
288 #define TMP102_DEV_PM_OPS NULL
289 #endif /* CONFIG_PM */
291 static const struct i2c_device_id tmp102_id[] = {
292 { "tmp102", 0 },
295 MODULE_DEVICE_TABLE(i2c, tmp102_id);
297 static struct i2c_driver tmp102_driver = {
298 .driver.name = DRIVER_NAME,
299 .driver.pm = TMP102_DEV_PM_OPS,
300 .probe = tmp102_probe,
301 .remove = __devexit_p(tmp102_remove),
302 .id_table = tmp102_id,
305 static int __init tmp102_init(void)
307 return i2c_add_driver(&tmp102_driver);
309 module_init(tmp102_init);
311 static void __exit tmp102_exit(void)
313 i2c_del_driver(&tmp102_driver);
315 module_exit(tmp102_exit);
317 MODULE_AUTHOR("Steven King <sfking@fdwdc.com>");
318 MODULE_DESCRIPTION("Texas Instruments TMP102 temperature sensor driver");
319 MODULE_LICENSE("GPL");