iwlwifi: introduce host commands callbacks
[linux/fpc-iii.git] / drivers / hwmon / lm77.c
blob36d5a8c3ad8c33e3327b62dace2ec684dec57bec
1 /*
2 lm77.c - Part of lm_sensors, Linux kernel modules for hardware
3 monitoring
5 Copyright (c) 2004 Andras BALI <drewie@freemail.hu>
7 Heavily based on lm75.c by Frodo Looijaard <frodol@dds.nl>. The LM77
8 is a temperature sensor and thermal window comparator with 0.5 deg
9 resolution made by National Semiconductor. Complete datasheet can be
10 obtained at their site:
11 http://www.national.com/pf/LM/LM77.html
13 This program is free software; you can redistribute it and/or modify
14 it under the terms of the GNU General Public License as published by
15 the Free Software Foundation; either version 2 of the License, or
16 (at your option) any later version.
18 This program is distributed in the hope that it will be useful,
19 but WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 GNU General Public License for more details.
23 You should have received a copy of the GNU General Public License
24 along with this program; if not, write to the Free Software
25 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/slab.h>
31 #include <linux/jiffies.h>
32 #include <linux/i2c.h>
33 #include <linux/hwmon.h>
34 #include <linux/hwmon-sysfs.h>
35 #include <linux/err.h>
36 #include <linux/mutex.h>
38 /* Addresses to scan */
39 static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
40 I2C_CLIENT_END };
42 /* Insmod parameters */
43 I2C_CLIENT_INSMOD_1(lm77);
45 /* The LM77 registers */
46 #define LM77_REG_TEMP 0x00
47 #define LM77_REG_CONF 0x01
48 #define LM77_REG_TEMP_HYST 0x02
49 #define LM77_REG_TEMP_CRIT 0x03
50 #define LM77_REG_TEMP_MIN 0x04
51 #define LM77_REG_TEMP_MAX 0x05
53 /* Each client has this additional data */
54 struct lm77_data {
55 struct i2c_client client;
56 struct device *hwmon_dev;
57 struct mutex update_lock;
58 char valid;
59 unsigned long last_updated; /* In jiffies */
60 int temp_input; /* Temperatures */
61 int temp_crit;
62 int temp_min;
63 int temp_max;
64 int temp_hyst;
65 u8 alarms;
68 static int lm77_attach_adapter(struct i2c_adapter *adapter);
69 static int lm77_detect(struct i2c_adapter *adapter, int address, int kind);
70 static void lm77_init_client(struct i2c_client *client);
71 static int lm77_detach_client(struct i2c_client *client);
72 static u16 lm77_read_value(struct i2c_client *client, u8 reg);
73 static int lm77_write_value(struct i2c_client *client, u8 reg, u16 value);
75 static struct lm77_data *lm77_update_device(struct device *dev);
78 /* This is the driver that will be inserted */
79 static struct i2c_driver lm77_driver = {
80 .driver = {
81 .name = "lm77",
83 .attach_adapter = lm77_attach_adapter,
84 .detach_client = lm77_detach_client,
87 /* straight from the datasheet */
88 #define LM77_TEMP_MIN (-55000)
89 #define LM77_TEMP_MAX 125000
91 /* In the temperature registers, the low 3 bits are not part of the
92 temperature values; they are the status bits. */
93 static inline s16 LM77_TEMP_TO_REG(int temp)
95 int ntemp = SENSORS_LIMIT(temp, LM77_TEMP_MIN, LM77_TEMP_MAX);
96 return (ntemp / 500) * 8;
99 static inline int LM77_TEMP_FROM_REG(s16 reg)
101 return (reg / 8) * 500;
104 /* sysfs stuff */
106 /* read routines for temperature limits */
107 #define show(value) \
108 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
110 struct lm77_data *data = lm77_update_device(dev); \
111 return sprintf(buf, "%d\n", data->value); \
114 show(temp_input);
115 show(temp_crit);
116 show(temp_min);
117 show(temp_max);
119 /* read routines for hysteresis values */
120 static ssize_t show_temp_crit_hyst(struct device *dev, struct device_attribute *attr, char *buf)
122 struct lm77_data *data = lm77_update_device(dev);
123 return sprintf(buf, "%d\n", data->temp_crit - data->temp_hyst);
125 static ssize_t show_temp_min_hyst(struct device *dev, struct device_attribute *attr, char *buf)
127 struct lm77_data *data = lm77_update_device(dev);
128 return sprintf(buf, "%d\n", data->temp_min + data->temp_hyst);
130 static ssize_t show_temp_max_hyst(struct device *dev, struct device_attribute *attr, char *buf)
132 struct lm77_data *data = lm77_update_device(dev);
133 return sprintf(buf, "%d\n", data->temp_max - data->temp_hyst);
136 /* write routines */
137 #define set(value, reg) \
138 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) \
140 struct i2c_client *client = to_i2c_client(dev); \
141 struct lm77_data *data = i2c_get_clientdata(client); \
142 long val = simple_strtol(buf, NULL, 10); \
144 mutex_lock(&data->update_lock); \
145 data->value = val; \
146 lm77_write_value(client, reg, LM77_TEMP_TO_REG(data->value)); \
147 mutex_unlock(&data->update_lock); \
148 return count; \
151 set(temp_min, LM77_REG_TEMP_MIN);
152 set(temp_max, LM77_REG_TEMP_MAX);
154 /* hysteresis is stored as a relative value on the chip, so it has to be
155 converted first */
156 static ssize_t set_temp_crit_hyst(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
158 struct i2c_client *client = to_i2c_client(dev);
159 struct lm77_data *data = i2c_get_clientdata(client);
160 unsigned long val = simple_strtoul(buf, NULL, 10);
162 mutex_lock(&data->update_lock);
163 data->temp_hyst = data->temp_crit - val;
164 lm77_write_value(client, LM77_REG_TEMP_HYST,
165 LM77_TEMP_TO_REG(data->temp_hyst));
166 mutex_unlock(&data->update_lock);
167 return count;
170 /* preserve hysteresis when setting T_crit */
171 static ssize_t set_temp_crit(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
173 struct i2c_client *client = to_i2c_client(dev);
174 struct lm77_data *data = i2c_get_clientdata(client);
175 long val = simple_strtoul(buf, NULL, 10);
176 int oldcrithyst;
178 mutex_lock(&data->update_lock);
179 oldcrithyst = data->temp_crit - data->temp_hyst;
180 data->temp_crit = val;
181 data->temp_hyst = data->temp_crit - oldcrithyst;
182 lm77_write_value(client, LM77_REG_TEMP_CRIT,
183 LM77_TEMP_TO_REG(data->temp_crit));
184 lm77_write_value(client, LM77_REG_TEMP_HYST,
185 LM77_TEMP_TO_REG(data->temp_hyst));
186 mutex_unlock(&data->update_lock);
187 return count;
190 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
191 char *buf)
193 int bitnr = to_sensor_dev_attr(attr)->index;
194 struct lm77_data *data = lm77_update_device(dev);
195 return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
198 static DEVICE_ATTR(temp1_input, S_IRUGO,
199 show_temp_input, NULL);
200 static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,
201 show_temp_crit, set_temp_crit);
202 static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
203 show_temp_min, set_temp_min);
204 static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
205 show_temp_max, set_temp_max);
207 static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO,
208 show_temp_crit_hyst, set_temp_crit_hyst);
209 static DEVICE_ATTR(temp1_min_hyst, S_IRUGO,
210 show_temp_min_hyst, NULL);
211 static DEVICE_ATTR(temp1_max_hyst, S_IRUGO,
212 show_temp_max_hyst, NULL);
214 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 2);
215 static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 0);
216 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 1);
218 static int lm77_attach_adapter(struct i2c_adapter *adapter)
220 if (!(adapter->class & I2C_CLASS_HWMON))
221 return 0;
222 return i2c_probe(adapter, &addr_data, lm77_detect);
225 static struct attribute *lm77_attributes[] = {
226 &dev_attr_temp1_input.attr,
227 &dev_attr_temp1_crit.attr,
228 &dev_attr_temp1_min.attr,
229 &dev_attr_temp1_max.attr,
230 &dev_attr_temp1_crit_hyst.attr,
231 &dev_attr_temp1_min_hyst.attr,
232 &dev_attr_temp1_max_hyst.attr,
233 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
234 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
235 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
236 NULL
239 static const struct attribute_group lm77_group = {
240 .attrs = lm77_attributes,
243 /* This function is called by i2c_probe */
244 static int lm77_detect(struct i2c_adapter *adapter, int address, int kind)
246 struct i2c_client *new_client;
247 struct lm77_data *data;
248 int err = 0;
249 const char *name = "";
251 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
252 I2C_FUNC_SMBUS_WORD_DATA))
253 goto exit;
255 /* OK. For now, we presume we have a valid client. We now create the
256 client structure, even though we cannot fill it completely yet.
257 But it allows us to access lm77_{read,write}_value. */
258 if (!(data = kzalloc(sizeof(struct lm77_data), GFP_KERNEL))) {
259 err = -ENOMEM;
260 goto exit;
263 new_client = &data->client;
264 i2c_set_clientdata(new_client, data);
265 new_client->addr = address;
266 new_client->adapter = adapter;
267 new_client->driver = &lm77_driver;
268 new_client->flags = 0;
270 /* Here comes the remaining detection. Since the LM77 has no
271 register dedicated to identification, we have to rely on the
272 following tricks:
274 1. the high 4 bits represent the sign and thus they should
275 always be the same
276 2. the high 3 bits are unused in the configuration register
277 3. addresses 0x06 and 0x07 return the last read value
278 4. registers cycling over 8-address boundaries
280 Word-sized registers are high-byte first. */
281 if (kind < 0) {
282 int i, cur, conf, hyst, crit, min, max;
284 /* addresses cycling */
285 cur = i2c_smbus_read_word_data(new_client, 0);
286 conf = i2c_smbus_read_byte_data(new_client, 1);
287 hyst = i2c_smbus_read_word_data(new_client, 2);
288 crit = i2c_smbus_read_word_data(new_client, 3);
289 min = i2c_smbus_read_word_data(new_client, 4);
290 max = i2c_smbus_read_word_data(new_client, 5);
291 for (i = 8; i <= 0xff; i += 8)
292 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
293 || i2c_smbus_read_word_data(new_client, i + 2) != hyst
294 || i2c_smbus_read_word_data(new_client, i + 3) != crit
295 || i2c_smbus_read_word_data(new_client, i + 4) != min
296 || i2c_smbus_read_word_data(new_client, i + 5) != max)
297 goto exit_free;
299 /* sign bits */
300 if (((cur & 0x00f0) != 0xf0 && (cur & 0x00f0) != 0x0)
301 || ((hyst & 0x00f0) != 0xf0 && (hyst & 0x00f0) != 0x0)
302 || ((crit & 0x00f0) != 0xf0 && (crit & 0x00f0) != 0x0)
303 || ((min & 0x00f0) != 0xf0 && (min & 0x00f0) != 0x0)
304 || ((max & 0x00f0) != 0xf0 && (max & 0x00f0) != 0x0))
305 goto exit_free;
307 /* unused bits */
308 if (conf & 0xe0)
309 goto exit_free;
311 /* 0x06 and 0x07 return the last read value */
312 cur = i2c_smbus_read_word_data(new_client, 0);
313 if (i2c_smbus_read_word_data(new_client, 6) != cur
314 || i2c_smbus_read_word_data(new_client, 7) != cur)
315 goto exit_free;
316 hyst = i2c_smbus_read_word_data(new_client, 2);
317 if (i2c_smbus_read_word_data(new_client, 6) != hyst
318 || i2c_smbus_read_word_data(new_client, 7) != hyst)
319 goto exit_free;
320 min = i2c_smbus_read_word_data(new_client, 4);
321 if (i2c_smbus_read_word_data(new_client, 6) != min
322 || i2c_smbus_read_word_data(new_client, 7) != min)
323 goto exit_free;
327 /* Determine the chip type - only one kind supported! */
328 if (kind <= 0)
329 kind = lm77;
331 if (kind == lm77) {
332 name = "lm77";
335 /* Fill in the remaining client fields and put it into the global list */
336 strlcpy(new_client->name, name, I2C_NAME_SIZE);
337 data->valid = 0;
338 mutex_init(&data->update_lock);
340 /* Tell the I2C layer a new client has arrived */
341 if ((err = i2c_attach_client(new_client)))
342 goto exit_free;
344 /* Initialize the LM77 chip */
345 lm77_init_client(new_client);
347 /* Register sysfs hooks */
348 if ((err = sysfs_create_group(&new_client->dev.kobj, &lm77_group)))
349 goto exit_detach;
351 data->hwmon_dev = hwmon_device_register(&new_client->dev);
352 if (IS_ERR(data->hwmon_dev)) {
353 err = PTR_ERR(data->hwmon_dev);
354 goto exit_remove;
357 return 0;
359 exit_remove:
360 sysfs_remove_group(&new_client->dev.kobj, &lm77_group);
361 exit_detach:
362 i2c_detach_client(new_client);
363 exit_free:
364 kfree(data);
365 exit:
366 return err;
369 static int lm77_detach_client(struct i2c_client *client)
371 struct lm77_data *data = i2c_get_clientdata(client);
372 hwmon_device_unregister(data->hwmon_dev);
373 sysfs_remove_group(&client->dev.kobj, &lm77_group);
374 i2c_detach_client(client);
375 kfree(data);
376 return 0;
379 /* All registers are word-sized, except for the configuration register.
380 The LM77 uses the high-byte first convention. */
381 static u16 lm77_read_value(struct i2c_client *client, u8 reg)
383 if (reg == LM77_REG_CONF)
384 return i2c_smbus_read_byte_data(client, reg);
385 else
386 return swab16(i2c_smbus_read_word_data(client, reg));
389 static int lm77_write_value(struct i2c_client *client, u8 reg, u16 value)
391 if (reg == LM77_REG_CONF)
392 return i2c_smbus_write_byte_data(client, reg, value);
393 else
394 return i2c_smbus_write_word_data(client, reg, swab16(value));
397 static void lm77_init_client(struct i2c_client *client)
399 /* Initialize the LM77 chip - turn off shutdown mode */
400 int conf = lm77_read_value(client, LM77_REG_CONF);
401 if (conf & 1)
402 lm77_write_value(client, LM77_REG_CONF, conf & 0xfe);
405 static struct lm77_data *lm77_update_device(struct device *dev)
407 struct i2c_client *client = to_i2c_client(dev);
408 struct lm77_data *data = i2c_get_clientdata(client);
410 mutex_lock(&data->update_lock);
412 if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
413 || !data->valid) {
414 dev_dbg(&client->dev, "Starting lm77 update\n");
415 data->temp_input =
416 LM77_TEMP_FROM_REG(lm77_read_value(client,
417 LM77_REG_TEMP));
418 data->temp_hyst =
419 LM77_TEMP_FROM_REG(lm77_read_value(client,
420 LM77_REG_TEMP_HYST));
421 data->temp_crit =
422 LM77_TEMP_FROM_REG(lm77_read_value(client,
423 LM77_REG_TEMP_CRIT));
424 data->temp_min =
425 LM77_TEMP_FROM_REG(lm77_read_value(client,
426 LM77_REG_TEMP_MIN));
427 data->temp_max =
428 LM77_TEMP_FROM_REG(lm77_read_value(client,
429 LM77_REG_TEMP_MAX));
430 data->alarms =
431 lm77_read_value(client, LM77_REG_TEMP) & 0x0007;
432 data->last_updated = jiffies;
433 data->valid = 1;
436 mutex_unlock(&data->update_lock);
438 return data;
441 static int __init sensors_lm77_init(void)
443 return i2c_add_driver(&lm77_driver);
446 static void __exit sensors_lm77_exit(void)
448 i2c_del_driver(&lm77_driver);
451 MODULE_AUTHOR("Andras BALI <drewie@freemail.hu>");
452 MODULE_DESCRIPTION("LM77 driver");
453 MODULE_LICENSE("GPL");
455 module_init(sensors_lm77_init);
456 module_exit(sensors_lm77_exit);