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authorJeff Garzik <jgarzik@pobox.com>2005-07-13 16:23:51 -0400
committerJeff Garzik <jgarzik@pobox.com>2005-07-13 16:23:51 -0400
commit327309e899662b482c58cf25f574513d38b5788c (patch)
tree069de438aa0e92dd9b6ba28e6b207e2cd07151a5 /drivers/hwmon/lm77.c
parent0c168775709faa74c1b87f1e61046e0c51ade7f3 (diff)
parentc32511e2718618f0b53479eb36e07439aa363a74 (diff)
Merge upstream 2.6.13-rc3 into ieee80211 branch of netdev-2.6.
Diffstat (limited to 'drivers/hwmon/lm77.c')
-rw-r--r--drivers/hwmon/lm77.c420
1 files changed, 420 insertions, 0 deletions
diff --git a/drivers/hwmon/lm77.c b/drivers/hwmon/lm77.c
new file mode 100644
index 000000000000..b98f44952997
--- /dev/null
+++ b/drivers/hwmon/lm77.c
@@ -0,0 +1,420 @@
1/*
2 lm77.c - Part of lm_sensors, Linux kernel modules for hardware
3 monitoring
4
5 Copyright (c) 2004 Andras BALI <drewie@freemail.hu>
6
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
12
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.
17
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.
22
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.
26*/
27
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/i2c-sensor.h>
34
35
36/* Addresses to scan */
37static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, I2C_CLIENT_END };
38static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
39
40/* Insmod parameters */
41SENSORS_INSMOD_1(lm77);
42
43/* The LM77 registers */
44#define LM77_REG_TEMP 0x00
45#define LM77_REG_CONF 0x01
46#define LM77_REG_TEMP_HYST 0x02
47#define LM77_REG_TEMP_CRIT 0x03
48#define LM77_REG_TEMP_MIN 0x04
49#define LM77_REG_TEMP_MAX 0x05
50
51/* Each client has this additional data */
52struct lm77_data {
53 struct i2c_client client;
54 struct semaphore update_lock;
55 char valid;
56 unsigned long last_updated; /* In jiffies */
57 int temp_input; /* Temperatures */
58 int temp_crit;
59 int temp_min;
60 int temp_max;
61 int temp_hyst;
62 u8 alarms;
63};
64
65static int lm77_attach_adapter(struct i2c_adapter *adapter);
66static int lm77_detect(struct i2c_adapter *adapter, int address, int kind);
67static void lm77_init_client(struct i2c_client *client);
68static int lm77_detach_client(struct i2c_client *client);
69static u16 lm77_read_value(struct i2c_client *client, u8 reg);
70static int lm77_write_value(struct i2c_client *client, u8 reg, u16 value);
71
72static struct lm77_data *lm77_update_device(struct device *dev);
73
74
75/* This is the driver that will be inserted */
76static struct i2c_driver lm77_driver = {
77 .owner = THIS_MODULE,
78 .name = "lm77",
79 .flags = I2C_DF_NOTIFY,
80 .attach_adapter = lm77_attach_adapter,
81 .detach_client = lm77_detach_client,
82};
83
84/* straight from the datasheet */
85#define LM77_TEMP_MIN (-55000)
86#define LM77_TEMP_MAX 125000
87
88/* In the temperature registers, the low 3 bits are not part of the
89 temperature values; they are the status bits. */
90static inline u16 LM77_TEMP_TO_REG(int temp)
91{
92 int ntemp = SENSORS_LIMIT(temp, LM77_TEMP_MIN, LM77_TEMP_MAX);
93 return (u16)((ntemp / 500) * 8);
94}
95
96static inline int LM77_TEMP_FROM_REG(u16 reg)
97{
98 return ((int)reg / 8) * 500;
99}
100
101/* sysfs stuff */
102
103/* read routines for temperature limits */
104#define show(value) \
105static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
106{ \
107 struct lm77_data *data = lm77_update_device(dev); \
108 return sprintf(buf, "%d\n", data->value); \
109}
110
111show(temp_input);
112show(temp_crit);
113show(temp_min);
114show(temp_max);
115show(alarms);
116
117/* read routines for hysteresis values */
118static ssize_t show_temp_crit_hyst(struct device *dev, struct device_attribute *attr, char *buf)
119{
120 struct lm77_data *data = lm77_update_device(dev);
121 return sprintf(buf, "%d\n", data->temp_crit - data->temp_hyst);
122}
123static ssize_t show_temp_min_hyst(struct device *dev, struct device_attribute *attr, char *buf)
124{
125 struct lm77_data *data = lm77_update_device(dev);
126 return sprintf(buf, "%d\n", data->temp_min + data->temp_hyst);
127}
128static ssize_t show_temp_max_hyst(struct device *dev, struct device_attribute *attr, char *buf)
129{
130 struct lm77_data *data = lm77_update_device(dev);
131 return sprintf(buf, "%d\n", data->temp_max - data->temp_hyst);
132}
133
134/* write routines */
135#define set(value, reg) \
136static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) \
137{ \
138 struct i2c_client *client = to_i2c_client(dev); \
139 struct lm77_data *data = i2c_get_clientdata(client); \
140 long val = simple_strtoul(buf, NULL, 10); \
141 \
142 down(&data->update_lock); \
143 data->value = val; \
144 lm77_write_value(client, reg, LM77_TEMP_TO_REG(data->value)); \
145 up(&data->update_lock); \
146 return count; \
147}
148
149set(temp_min, LM77_REG_TEMP_MIN);
150set(temp_max, LM77_REG_TEMP_MAX);
151
152/* hysteresis is stored as a relative value on the chip, so it has to be
153 converted first */
154static ssize_t set_temp_crit_hyst(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
155{
156 struct i2c_client *client = to_i2c_client(dev);
157 struct lm77_data *data = i2c_get_clientdata(client);
158 unsigned long val = simple_strtoul(buf, NULL, 10);
159
160 down(&data->update_lock);
161 data->temp_hyst = data->temp_crit - val;
162 lm77_write_value(client, LM77_REG_TEMP_HYST,
163 LM77_TEMP_TO_REG(data->temp_hyst));
164 up(&data->update_lock);
165 return count;
166}
167
168/* preserve hysteresis when setting T_crit */
169static ssize_t set_temp_crit(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
170{
171 struct i2c_client *client = to_i2c_client(dev);
172 struct lm77_data *data = i2c_get_clientdata(client);
173 long val = simple_strtoul(buf, NULL, 10);
174 int oldcrithyst;
175
176 down(&data->update_lock);
177 oldcrithyst = data->temp_crit - data->temp_hyst;
178 data->temp_crit = val;
179 data->temp_hyst = data->temp_crit - oldcrithyst;
180 lm77_write_value(client, LM77_REG_TEMP_CRIT,
181 LM77_TEMP_TO_REG(data->temp_crit));
182 lm77_write_value(client, LM77_REG_TEMP_HYST,
183 LM77_TEMP_TO_REG(data->temp_hyst));
184 up(&data->update_lock);
185 return count;
186}
187
188static DEVICE_ATTR(temp1_input, S_IRUGO,
189 show_temp_input, NULL);
190static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,
191 show_temp_crit, set_temp_crit);
192static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
193 show_temp_min, set_temp_min);
194static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
195 show_temp_max, set_temp_max);
196
197static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO,
198 show_temp_crit_hyst, set_temp_crit_hyst);
199static DEVICE_ATTR(temp1_min_hyst, S_IRUGO,
200 show_temp_min_hyst, NULL);
201static DEVICE_ATTR(temp1_max_hyst, S_IRUGO,
202 show_temp_max_hyst, NULL);
203
204static DEVICE_ATTR(alarms, S_IRUGO,
205 show_alarms, NULL);
206
207static int lm77_attach_adapter(struct i2c_adapter *adapter)
208{
209 if (!(adapter->class & I2C_CLASS_HWMON))
210 return 0;
211 return i2c_detect(adapter, &addr_data, lm77_detect);
212}
213
214/* This function is called by i2c_detect */
215static int lm77_detect(struct i2c_adapter *adapter, int address, int kind)
216{
217 struct i2c_client *new_client;
218 struct lm77_data *data;
219 int err = 0;
220 const char *name = "";
221
222 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
223 I2C_FUNC_SMBUS_WORD_DATA))
224 goto exit;
225
226 /* OK. For now, we presume we have a valid client. We now create the
227 client structure, even though we cannot fill it completely yet.
228 But it allows us to access lm77_{read,write}_value. */
229 if (!(data = kmalloc(sizeof(struct lm77_data), GFP_KERNEL))) {
230 err = -ENOMEM;
231 goto exit;
232 }
233 memset(data, 0, sizeof(struct lm77_data));
234
235 new_client = &data->client;
236 i2c_set_clientdata(new_client, data);
237 new_client->addr = address;
238 new_client->adapter = adapter;
239 new_client->driver = &lm77_driver;
240 new_client->flags = 0;
241
242 /* Here comes the remaining detection. Since the LM77 has no
243 register dedicated to identification, we have to rely on the
244 following tricks:
245
246 1. the high 4 bits represent the sign and thus they should
247 always be the same
248 2. the high 3 bits are unused in the configuration register
249 3. addresses 0x06 and 0x07 return the last read value
250 4. registers cycling over 8-address boundaries
251
252 Word-sized registers are high-byte first. */
253 if (kind < 0) {
254 int i, cur, conf, hyst, crit, min, max;
255
256 /* addresses cycling */
257 cur = i2c_smbus_read_word_data(new_client, 0);
258 conf = i2c_smbus_read_byte_data(new_client, 1);
259 hyst = i2c_smbus_read_word_data(new_client, 2);
260 crit = i2c_smbus_read_word_data(new_client, 3);
261 min = i2c_smbus_read_word_data(new_client, 4);
262 max = i2c_smbus_read_word_data(new_client, 5);
263 for (i = 8; i <= 0xff; i += 8)
264 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
265 || i2c_smbus_read_word_data(new_client, i + 2) != hyst
266 || i2c_smbus_read_word_data(new_client, i + 3) != crit
267 || i2c_smbus_read_word_data(new_client, i + 4) != min
268 || i2c_smbus_read_word_data(new_client, i + 5) != max)
269 goto exit_free;
270
271 /* sign bits */
272 if (((cur & 0x00f0) != 0xf0 && (cur & 0x00f0) != 0x0)
273 || ((hyst & 0x00f0) != 0xf0 && (hyst & 0x00f0) != 0x0)
274 || ((crit & 0x00f0) != 0xf0 && (crit & 0x00f0) != 0x0)
275 || ((min & 0x00f0) != 0xf0 && (min & 0x00f0) != 0x0)
276 || ((max & 0x00f0) != 0xf0 && (max & 0x00f0) != 0x0))
277 goto exit_free;
278
279 /* unused bits */
280 if (conf & 0xe0)
281 goto exit_free;
282
283 /* 0x06 and 0x07 return the last read value */
284 cur = i2c_smbus_read_word_data(new_client, 0);
285 if (i2c_smbus_read_word_data(new_client, 6) != cur
286 || i2c_smbus_read_word_data(new_client, 7) != cur)
287 goto exit_free;
288 hyst = i2c_smbus_read_word_data(new_client, 2);
289 if (i2c_smbus_read_word_data(new_client, 6) != hyst
290 || i2c_smbus_read_word_data(new_client, 7) != hyst)
291 goto exit_free;
292 min = i2c_smbus_read_word_data(new_client, 4);
293 if (i2c_smbus_read_word_data(new_client, 6) != min
294 || i2c_smbus_read_word_data(new_client, 7) != min)
295 goto exit_free;
296
297 }
298
299 /* Determine the chip type - only one kind supported! */
300 if (kind <= 0)
301 kind = lm77;
302
303 if (kind == lm77) {
304 name = "lm77";
305 }
306
307 /* Fill in the remaining client fields and put it into the global list */
308 strlcpy(new_client->name, name, I2C_NAME_SIZE);
309 data->valid = 0;
310 init_MUTEX(&data->update_lock);
311
312 /* Tell the I2C layer a new client has arrived */
313 if ((err = i2c_attach_client(new_client)))
314 goto exit_free;
315
316 /* Initialize the LM77 chip */
317 lm77_init_client(new_client);
318
319 /* Register sysfs hooks */
320 device_create_file(&new_client->dev, &dev_attr_temp1_input);
321 device_create_file(&new_client->dev, &dev_attr_temp1_crit);
322 device_create_file(&new_client->dev, &dev_attr_temp1_min);
323 device_create_file(&new_client->dev, &dev_attr_temp1_max);
324 device_create_file(&new_client->dev, &dev_attr_temp1_crit_hyst);
325 device_create_file(&new_client->dev, &dev_attr_temp1_min_hyst);
326 device_create_file(&new_client->dev, &dev_attr_temp1_max_hyst);
327 device_create_file(&new_client->dev, &dev_attr_alarms);
328 return 0;
329
330exit_free:
331 kfree(data);
332exit:
333 return err;
334}
335
336static int lm77_detach_client(struct i2c_client *client)
337{
338 i2c_detach_client(client);
339 kfree(i2c_get_clientdata(client));
340 return 0;
341}
342
343/* All registers are word-sized, except for the configuration register.
344 The LM77 uses the high-byte first convention. */
345static u16 lm77_read_value(struct i2c_client *client, u8 reg)
346{
347 if (reg == LM77_REG_CONF)
348 return i2c_smbus_read_byte_data(client, reg);
349 else
350 return swab16(i2c_smbus_read_word_data(client, reg));
351}
352
353static int lm77_write_value(struct i2c_client *client, u8 reg, u16 value)
354{
355 if (reg == LM77_REG_CONF)
356 return i2c_smbus_write_byte_data(client, reg, value);
357 else
358 return i2c_smbus_write_word_data(client, reg, swab16(value));
359}
360
361static void lm77_init_client(struct i2c_client *client)
362{
363 /* Initialize the LM77 chip - turn off shutdown mode */
364 int conf = lm77_read_value(client, LM77_REG_CONF);
365 if (conf & 1)
366 lm77_write_value(client, LM77_REG_CONF, conf & 0xfe);
367}
368
369static struct lm77_data *lm77_update_device(struct device *dev)
370{
371 struct i2c_client *client = to_i2c_client(dev);
372 struct lm77_data *data = i2c_get_clientdata(client);
373
374 down(&data->update_lock);
375
376 if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
377 || !data->valid) {
378 dev_dbg(&client->dev, "Starting lm77 update\n");
379 data->temp_input =
380 LM77_TEMP_FROM_REG(lm77_read_value(client,
381 LM77_REG_TEMP));
382 data->temp_hyst =
383 LM77_TEMP_FROM_REG(lm77_read_value(client,
384 LM77_REG_TEMP_HYST));
385 data->temp_crit =
386 LM77_TEMP_FROM_REG(lm77_read_value(client,
387 LM77_REG_TEMP_CRIT));
388 data->temp_min =
389 LM77_TEMP_FROM_REG(lm77_read_value(client,
390 LM77_REG_TEMP_MIN));
391 data->temp_max =
392 LM77_TEMP_FROM_REG(lm77_read_value(client,
393 LM77_REG_TEMP_MAX));
394 data->alarms =
395 lm77_read_value(client, LM77_REG_TEMP) & 0x0007;
396 data->last_updated = jiffies;
397 data->valid = 1;
398 }
399
400 up(&data->update_lock);
401
402 return data;
403}
404
405static int __init sensors_lm77_init(void)
406{
407 return i2c_add_driver(&lm77_driver);
408}
409
410static void __exit sensors_lm77_exit(void)
411{
412 i2c_del_driver(&lm77_driver);
413}
414
415MODULE_AUTHOR("Andras BALI <drewie@freemail.hu>");
416MODULE_DESCRIPTION("LM77 driver");
417MODULE_LICENSE("GPL");
418
419module_init(sensors_lm77_init);
420module_exit(sensors_lm77_exit);