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Diffstat (limited to 'drivers/i2c/chips/lm92.c')
-rw-r--r--drivers/i2c/chips/lm92.c429
1 files changed, 0 insertions, 429 deletions
diff --git a/drivers/i2c/chips/lm92.c b/drivers/i2c/chips/lm92.c
deleted file mode 100644
index 215c8e40ffdd..000000000000
--- a/drivers/i2c/chips/lm92.c
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@@ -1,429 +0,0 @@
1/*
2 * lm92 - Hardware monitoring driver
3 * Copyright (C) 2005 Jean Delvare <khali@linux-fr.org>
4 *
5 * Based on the lm90 driver, with some ideas taken from the lm_sensors
6 * lm92 driver as well.
7 *
8 * The LM92 is a sensor chip made by National Semiconductor. It reports
9 * its own temperature with a 0.0625 deg resolution and a 0.33 deg
10 * accuracy. Complete datasheet can be obtained from National's website
11 * at:
12 * http://www.national.com/pf/LM/LM92.html
13 *
14 * This driver also supports the MAX6635 sensor chip made by Maxim.
15 * This chip is compatible with the LM92, but has a lesser accuracy
16 * (1.0 deg). Complete datasheet can be obtained from Maxim's website
17 * at:
18 * http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3074
19 *
20 * Since the LM92 was the first chipset supported by this driver, most
21 * comments will refer to this chipset, but are actually general and
22 * concern all supported chipsets, unless mentioned otherwise.
23 *
24 * Support could easily be added for the National Semiconductor LM76
25 * and Maxim MAX6633 and MAX6634 chips, which are mostly compatible
26 * with the LM92.
27 *
28 * This program is free software; you can redistribute it and/or modify
29 * it under the terms of the GNU General Public License as published by
30 * the Free Software Foundation; either version 2 of the License, or
31 * (at your option) any later version.
32 *
33 * This program is distributed in the hope that it will be useful,
34 * but WITHOUT ANY WARRANTY; without even the implied warranty of
35 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
36 * GNU General Public License for more details.
37 *
38 * You should have received a copy of the GNU General Public License
39 * along with this program; if not, write to the Free Software
40 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
41 */
42
43#include <linux/module.h>
44#include <linux/init.h>
45#include <linux/slab.h>
46#include <linux/i2c.h>
47#include <linux/i2c-sensor.h>
48
49
50/* The LM92 and MAX6635 have 2 two-state pins for address selection,
51 resulting in 4 possible addresses. */
52static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
53 I2C_CLIENT_END };
54static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END };
55
56/* Insmod parameters */
57SENSORS_INSMOD_1(lm92);
58
59/* The LM92 registers */
60#define LM92_REG_CONFIG 0x01 /* 8-bit, RW */
61#define LM92_REG_TEMP 0x00 /* 16-bit, RO */
62#define LM92_REG_TEMP_HYST 0x02 /* 16-bit, RW */
63#define LM92_REG_TEMP_CRIT 0x03 /* 16-bit, RW */
64#define LM92_REG_TEMP_LOW 0x04 /* 16-bit, RW */
65#define LM92_REG_TEMP_HIGH 0x05 /* 16-bit, RW */
66#define LM92_REG_MAN_ID 0x07 /* 16-bit, RO, LM92 only */
67
68/* The LM92 uses signed 13-bit values with LSB = 0.0625 degree Celsius,
69 left-justified in 16-bit registers. No rounding is done, with such
70 a resolution it's just not worth it. Note that the MAX6635 doesn't
71 make use of the 4 lower bits for limits (i.e. effective resolution
72 for limits is 1 degree Celsius). */
73static inline int TEMP_FROM_REG(s16 reg)
74{
75 return reg / 8 * 625 / 10;
76}
77
78static inline s16 TEMP_TO_REG(int val)
79{
80 if (val <= -60000)
81 return -60000 * 10 / 625 * 8;
82 if (val >= 160000)
83 return 160000 * 10 / 625 * 8;
84 return val * 10 / 625 * 8;
85}
86
87/* Alarm flags are stored in the 3 LSB of the temperature register */
88static inline u8 ALARMS_FROM_REG(s16 reg)
89{
90 return reg & 0x0007;
91}
92
93/* Driver data (common to all clients) */
94static struct i2c_driver lm92_driver;
95
96/* Client data (each client gets its own) */
97struct lm92_data {
98 struct i2c_client client;
99 struct semaphore update_lock;
100 char valid; /* zero until following fields are valid */
101 unsigned long last_updated; /* in jiffies */
102
103 /* registers values */
104 s16 temp1_input, temp1_crit, temp1_min, temp1_max, temp1_hyst;
105};
106
107
108/*
109 * Sysfs attributes and callback functions
110 */
111
112static struct lm92_data *lm92_update_device(struct device *dev)
113{
114 struct i2c_client *client = to_i2c_client(dev);
115 struct lm92_data *data = i2c_get_clientdata(client);
116
117 down(&data->update_lock);
118
119 if (time_after(jiffies, data->last_updated + HZ)
120 || !data->valid) {
121 dev_dbg(&client->dev, "Updating lm92 data\n");
122 data->temp1_input = swab16(i2c_smbus_read_word_data(client,
123 LM92_REG_TEMP));
124 data->temp1_hyst = swab16(i2c_smbus_read_word_data(client,
125 LM92_REG_TEMP_HYST));
126 data->temp1_crit = swab16(i2c_smbus_read_word_data(client,
127 LM92_REG_TEMP_CRIT));
128 data->temp1_min = swab16(i2c_smbus_read_word_data(client,
129 LM92_REG_TEMP_LOW));
130 data->temp1_max = swab16(i2c_smbus_read_word_data(client,
131 LM92_REG_TEMP_HIGH));
132
133 data->last_updated = jiffies;
134 data->valid = 1;
135 }
136
137 up(&data->update_lock);
138
139 return data;
140}
141
142#define show_temp(value) \
143static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
144{ \
145 struct lm92_data *data = lm92_update_device(dev); \
146 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->value)); \
147}
148show_temp(temp1_input);
149show_temp(temp1_crit);
150show_temp(temp1_min);
151show_temp(temp1_max);
152
153#define set_temp(value, reg) \
154static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
155 size_t count) \
156{ \
157 struct i2c_client *client = to_i2c_client(dev); \
158 struct lm92_data *data = i2c_get_clientdata(client); \
159 long val = simple_strtol(buf, NULL, 10); \
160 \
161 down(&data->update_lock); \
162 data->value = TEMP_TO_REG(val); \
163 i2c_smbus_write_word_data(client, reg, swab16(data->value)); \
164 up(&data->update_lock); \
165 return count; \
166}
167set_temp(temp1_crit, LM92_REG_TEMP_CRIT);
168set_temp(temp1_min, LM92_REG_TEMP_LOW);
169set_temp(temp1_max, LM92_REG_TEMP_HIGH);
170
171static ssize_t show_temp1_crit_hyst(struct device *dev, struct device_attribute *attr, char *buf)
172{
173 struct lm92_data *data = lm92_update_device(dev);
174 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp1_crit)
175 - TEMP_FROM_REG(data->temp1_hyst));
176}
177static ssize_t show_temp1_max_hyst(struct device *dev, struct device_attribute *attr, char *buf)
178{
179 struct lm92_data *data = lm92_update_device(dev);
180 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp1_max)
181 - TEMP_FROM_REG(data->temp1_hyst));
182}
183static ssize_t show_temp1_min_hyst(struct device *dev, struct device_attribute *attr, char *buf)
184{
185 struct lm92_data *data = lm92_update_device(dev);
186 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp1_min)
187 + TEMP_FROM_REG(data->temp1_hyst));
188}
189
190static ssize_t set_temp1_crit_hyst(struct device *dev, struct device_attribute *attr, const char *buf,
191 size_t count)
192{
193 struct i2c_client *client = to_i2c_client(dev);
194 struct lm92_data *data = i2c_get_clientdata(client);
195 long val = simple_strtol(buf, NULL, 10);
196
197 down(&data->update_lock);
198 data->temp1_hyst = TEMP_FROM_REG(data->temp1_crit) - val;
199 i2c_smbus_write_word_data(client, LM92_REG_TEMP_HYST,
200 swab16(TEMP_TO_REG(data->temp1_hyst)));
201 up(&data->update_lock);
202 return count;
203}
204
205static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
206{
207 struct lm92_data *data = lm92_update_device(dev);
208 return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->temp1_input));
209}
210
211static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp1_input, NULL);
212static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_temp1_crit,
213 set_temp1_crit);
214static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_temp1_crit_hyst,
215 set_temp1_crit_hyst);
216static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp1_min,
217 set_temp1_min);
218static DEVICE_ATTR(temp1_min_hyst, S_IRUGO, show_temp1_min_hyst, NULL);
219static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp1_max,
220 set_temp1_max);
221static DEVICE_ATTR(temp1_max_hyst, S_IRUGO, show_temp1_max_hyst, NULL);
222static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
223
224
225/*
226 * Detection and registration
227 */
228
229static void lm92_init_client(struct i2c_client *client)
230{
231 u8 config;
232
233 /* Start the conversions if needed */
234 config = i2c_smbus_read_byte_data(client, LM92_REG_CONFIG);
235 if (config & 0x01)
236 i2c_smbus_write_byte_data(client, LM92_REG_CONFIG,
237 config & 0xFE);
238}
239
240/* The MAX6635 has no identification register, so we have to use tricks
241 to identify it reliably. This is somewhat slow.
242 Note that we do NOT rely on the 2 MSB of the configuration register
243 always reading 0, as suggested by the datasheet, because it was once
244 reported not to be true. */
245static int max6635_check(struct i2c_client *client)
246{
247 u16 temp_low, temp_high, temp_hyst, temp_crit;
248 u8 conf;
249 int i;
250
251 /* No manufacturer ID register, so a read from this address will
252 always return the last read value. */
253 temp_low = i2c_smbus_read_word_data(client, LM92_REG_TEMP_LOW);
254 if (i2c_smbus_read_word_data(client, LM92_REG_MAN_ID) != temp_low)
255 return 0;
256 temp_high = i2c_smbus_read_word_data(client, LM92_REG_TEMP_HIGH);
257 if (i2c_smbus_read_word_data(client, LM92_REG_MAN_ID) != temp_high)
258 return 0;
259
260 /* Limits are stored as integer values (signed, 9-bit). */
261 if ((temp_low & 0x7f00) || (temp_high & 0x7f00))
262 return 0;
263 temp_hyst = i2c_smbus_read_word_data(client, LM92_REG_TEMP_HYST);
264 temp_crit = i2c_smbus_read_word_data(client, LM92_REG_TEMP_CRIT);
265 if ((temp_hyst & 0x7f00) || (temp_crit & 0x7f00))
266 return 0;
267
268 /* Registers addresses were found to cycle over 16-byte boundaries.
269 We don't test all registers with all offsets so as to save some
270 reads and time, but this should still be sufficient to dismiss
271 non-MAX6635 chips. */
272 conf = i2c_smbus_read_byte_data(client, LM92_REG_CONFIG);
273 for (i=16; i<96; i*=2) {
274 if (temp_hyst != i2c_smbus_read_word_data(client,
275 LM92_REG_TEMP_HYST + i - 16)
276 || temp_crit != i2c_smbus_read_word_data(client,
277 LM92_REG_TEMP_CRIT + i)
278 || temp_low != i2c_smbus_read_word_data(client,
279 LM92_REG_TEMP_LOW + i + 16)
280 || temp_high != i2c_smbus_read_word_data(client,
281 LM92_REG_TEMP_HIGH + i + 32)
282 || conf != i2c_smbus_read_byte_data(client,
283 LM92_REG_CONFIG + i))
284 return 0;
285 }
286
287 return 1;
288}
289
290/* The following function does more than just detection. If detection
291 succeeds, it also registers the new chip. */
292static int lm92_detect(struct i2c_adapter *adapter, int address, int kind)
293{
294 struct i2c_client *new_client;
295 struct lm92_data *data;
296 int err = 0;
297 char *name;
298
299 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
300 | I2C_FUNC_SMBUS_WORD_DATA))
301 goto exit;
302
303 if (!(data = kmalloc(sizeof(struct lm92_data), GFP_KERNEL))) {
304 err = -ENOMEM;
305 goto exit;
306 }
307 memset(data, 0, sizeof(struct lm92_data));
308
309 /* Fill in enough client fields so that we can read from the chip,
310 which is required for identication */
311 new_client = &data->client;
312 i2c_set_clientdata(new_client, data);
313 new_client->addr = address;
314 new_client->adapter = adapter;
315 new_client->driver = &lm92_driver;
316 new_client->flags = 0;
317
318 /* A negative kind means that the driver was loaded with no force
319 parameter (default), so we must identify the chip. */
320 if (kind < 0) {
321 u8 config = i2c_smbus_read_byte_data(new_client,
322 LM92_REG_CONFIG);
323 u16 man_id = i2c_smbus_read_word_data(new_client,
324 LM92_REG_MAN_ID);
325
326 if ((config & 0xe0) == 0x00
327 && man_id == 0x0180) {
328 pr_info("lm92: Found National Semiconductor LM92 chip\n");
329 kind = lm92;
330 } else
331 if (max6635_check(new_client)) {
332 pr_info("lm92: Found Maxim MAX6635 chip\n");
333 kind = lm92; /* No separate prefix */
334 }
335 else
336 goto exit_free;
337 } else
338 if (kind == 0) /* Default to an LM92 if forced */
339 kind = lm92;
340
341 /* Give it the proper name */
342 if (kind == lm92) {
343 name = "lm92";
344 } else { /* Supposedly cannot happen */
345 dev_dbg(&new_client->dev, "Kind out of range?\n");
346 goto exit_free;
347 }
348
349 /* Fill in the remaining client fields */
350 strlcpy(new_client->name, name, I2C_NAME_SIZE);
351 data->valid = 0;
352 init_MUTEX(&data->update_lock);
353
354 /* Tell the i2c subsystem a new client has arrived */
355 if ((err = i2c_attach_client(new_client)))
356 goto exit_free;
357
358 /* Initialize the chipset */
359 lm92_init_client(new_client);
360
361 /* Register sysfs hooks */
362 device_create_file(&new_client->dev, &dev_attr_temp1_input);
363 device_create_file(&new_client->dev, &dev_attr_temp1_crit);
364 device_create_file(&new_client->dev, &dev_attr_temp1_crit_hyst);
365 device_create_file(&new_client->dev, &dev_attr_temp1_min);
366 device_create_file(&new_client->dev, &dev_attr_temp1_min_hyst);
367 device_create_file(&new_client->dev, &dev_attr_temp1_max);
368 device_create_file(&new_client->dev, &dev_attr_temp1_max_hyst);
369 device_create_file(&new_client->dev, &dev_attr_alarms);
370
371 return 0;
372
373exit_free:
374 kfree(data);
375exit:
376 return err;
377}
378
379static int lm92_attach_adapter(struct i2c_adapter *adapter)
380{
381 if (!(adapter->class & I2C_CLASS_HWMON))
382 return 0;
383 return i2c_detect(adapter, &addr_data, lm92_detect);
384}
385
386static int lm92_detach_client(struct i2c_client *client)
387{
388 int err;
389
390 if ((err = i2c_detach_client(client))) {
391 dev_err(&client->dev, "Client deregistration failed, "
392 "client not detached.\n");
393 return err;
394 }
395
396 kfree(i2c_get_clientdata(client));
397 return 0;
398}
399
400
401/*
402 * Module and driver stuff
403 */
404
405static struct i2c_driver lm92_driver = {
406 .owner = THIS_MODULE,
407 .name = "lm92",
408 .id = I2C_DRIVERID_LM92,
409 .flags = I2C_DF_NOTIFY,
410 .attach_adapter = lm92_attach_adapter,
411 .detach_client = lm92_detach_client,
412};
413
414static int __init sensors_lm92_init(void)
415{
416 return i2c_add_driver(&lm92_driver);
417}
418
419static void __exit sensors_lm92_exit(void)
420{
421 i2c_del_driver(&lm92_driver);
422}
423
424MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
425MODULE_DESCRIPTION("LM92/MAX6635 driver");
426MODULE_LICENSE("GPL");
427
428module_init(sensors_lm92_init);
429module_exit(sensors_lm92_exit);
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-14 07:47:40 -0500