diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/i2c/chips/lm77.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/i2c/chips/lm77.c')
-rw-r--r-- | drivers/i2c/chips/lm77.c | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/drivers/i2c/chips/lm77.c b/drivers/i2c/chips/lm77.c new file mode 100644 index 000000000000..f56b7a37de75 --- /dev/null +++ b/drivers/i2c/chips/lm77.c | |||
@@ -0,0 +1,421 @@ | |||
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/config.h> | ||
29 | #include <linux/module.h> | ||
30 | #include <linux/init.h> | ||
31 | #include <linux/slab.h> | ||
32 | #include <linux/jiffies.h> | ||
33 | #include <linux/i2c.h> | ||
34 | #include <linux/i2c-sensor.h> | ||
35 | |||
36 | |||
37 | /* Addresses to scan */ | ||
38 | static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, I2C_CLIENT_END }; | ||
39 | static unsigned int normal_isa[] = { I2C_CLIENT_ISA_END }; | ||
40 | |||
41 | /* Insmod parameters */ | ||
42 | SENSORS_INSMOD_1(lm77); | ||
43 | |||
44 | /* The LM77 registers */ | ||
45 | #define LM77_REG_TEMP 0x00 | ||
46 | #define LM77_REG_CONF 0x01 | ||
47 | #define LM77_REG_TEMP_HYST 0x02 | ||
48 | #define LM77_REG_TEMP_CRIT 0x03 | ||
49 | #define LM77_REG_TEMP_MIN 0x04 | ||
50 | #define LM77_REG_TEMP_MAX 0x05 | ||
51 | |||
52 | /* Each client has this additional data */ | ||
53 | struct lm77_data { | ||
54 | struct i2c_client client; | ||
55 | struct semaphore update_lock; | ||
56 | char valid; | ||
57 | unsigned long last_updated; /* In jiffies */ | ||
58 | int temp_input; /* Temperatures */ | ||
59 | int temp_crit; | ||
60 | int temp_min; | ||
61 | int temp_max; | ||
62 | int temp_hyst; | ||
63 | u8 alarms; | ||
64 | }; | ||
65 | |||
66 | static int lm77_attach_adapter(struct i2c_adapter *adapter); | ||
67 | static int lm77_detect(struct i2c_adapter *adapter, int address, int kind); | ||
68 | static void lm77_init_client(struct i2c_client *client); | ||
69 | static int lm77_detach_client(struct i2c_client *client); | ||
70 | static u16 lm77_read_value(struct i2c_client *client, u8 reg); | ||
71 | static int lm77_write_value(struct i2c_client *client, u8 reg, u16 value); | ||
72 | |||
73 | static struct lm77_data *lm77_update_device(struct device *dev); | ||
74 | |||
75 | |||
76 | /* This is the driver that will be inserted */ | ||
77 | static struct i2c_driver lm77_driver = { | ||
78 | .owner = THIS_MODULE, | ||
79 | .name = "lm77", | ||
80 | .flags = I2C_DF_NOTIFY, | ||
81 | .attach_adapter = lm77_attach_adapter, | ||
82 | .detach_client = lm77_detach_client, | ||
83 | }; | ||
84 | |||
85 | /* straight from the datasheet */ | ||
86 | #define LM77_TEMP_MIN (-55000) | ||
87 | #define LM77_TEMP_MAX 125000 | ||
88 | |||
89 | /* In the temperature registers, the low 3 bits are not part of the | ||
90 | temperature values; they are the status bits. */ | ||
91 | static inline u16 LM77_TEMP_TO_REG(int temp) | ||
92 | { | ||
93 | int ntemp = SENSORS_LIMIT(temp, LM77_TEMP_MIN, LM77_TEMP_MAX); | ||
94 | return (u16)((ntemp / 500) * 8); | ||
95 | } | ||
96 | |||
97 | static inline int LM77_TEMP_FROM_REG(u16 reg) | ||
98 | { | ||
99 | return ((int)reg / 8) * 500; | ||
100 | } | ||
101 | |||
102 | /* sysfs stuff */ | ||
103 | |||
104 | /* read routines for temperature limits */ | ||
105 | #define show(value) \ | ||
106 | static ssize_t show_##value(struct device *dev, char *buf) \ | ||
107 | { \ | ||
108 | struct lm77_data *data = lm77_update_device(dev); \ | ||
109 | return sprintf(buf, "%d\n", data->value); \ | ||
110 | } | ||
111 | |||
112 | show(temp_input); | ||
113 | show(temp_crit); | ||
114 | show(temp_min); | ||
115 | show(temp_max); | ||
116 | show(alarms); | ||
117 | |||
118 | /* read routines for hysteresis values */ | ||
119 | static ssize_t show_temp_crit_hyst(struct device *dev, char *buf) | ||
120 | { | ||
121 | struct lm77_data *data = lm77_update_device(dev); | ||
122 | return sprintf(buf, "%d\n", data->temp_crit - data->temp_hyst); | ||
123 | } | ||
124 | static ssize_t show_temp_min_hyst(struct device *dev, char *buf) | ||
125 | { | ||
126 | struct lm77_data *data = lm77_update_device(dev); | ||
127 | return sprintf(buf, "%d\n", data->temp_min + data->temp_hyst); | ||
128 | } | ||
129 | static ssize_t show_temp_max_hyst(struct device *dev, char *buf) | ||
130 | { | ||
131 | struct lm77_data *data = lm77_update_device(dev); | ||
132 | return sprintf(buf, "%d\n", data->temp_max - data->temp_hyst); | ||
133 | } | ||
134 | |||
135 | /* write routines */ | ||
136 | #define set(value, reg) \ | ||
137 | static ssize_t set_##value(struct device *dev, const char *buf, size_t count) \ | ||
138 | { \ | ||
139 | struct i2c_client *client = to_i2c_client(dev); \ | ||
140 | struct lm77_data *data = i2c_get_clientdata(client); \ | ||
141 | long val = simple_strtoul(buf, NULL, 10); \ | ||
142 | \ | ||
143 | down(&data->update_lock); \ | ||
144 | data->value = val; \ | ||
145 | lm77_write_value(client, reg, LM77_TEMP_TO_REG(data->value)); \ | ||
146 | up(&data->update_lock); \ | ||
147 | return count; \ | ||
148 | } | ||
149 | |||
150 | set(temp_min, LM77_REG_TEMP_MIN); | ||
151 | set(temp_max, LM77_REG_TEMP_MAX); | ||
152 | |||
153 | /* hysteresis is stored as a relative value on the chip, so it has to be | ||
154 | converted first */ | ||
155 | static ssize_t set_temp_crit_hyst(struct device *dev, const char *buf, size_t count) | ||
156 | { | ||
157 | struct i2c_client *client = to_i2c_client(dev); | ||
158 | struct lm77_data *data = i2c_get_clientdata(client); | ||
159 | unsigned long val = simple_strtoul(buf, NULL, 10); | ||
160 | |||
161 | down(&data->update_lock); | ||
162 | data->temp_hyst = data->temp_crit - val; | ||
163 | lm77_write_value(client, LM77_REG_TEMP_HYST, | ||
164 | LM77_TEMP_TO_REG(data->temp_hyst)); | ||
165 | up(&data->update_lock); | ||
166 | return count; | ||
167 | } | ||
168 | |||
169 | /* preserve hysteresis when setting T_crit */ | ||
170 | static ssize_t set_temp_crit(struct device *dev, const char *buf, size_t count) | ||
171 | { | ||
172 | struct i2c_client *client = to_i2c_client(dev); | ||
173 | struct lm77_data *data = i2c_get_clientdata(client); | ||
174 | long val = simple_strtoul(buf, NULL, 10); | ||
175 | int oldcrithyst; | ||
176 | |||
177 | down(&data->update_lock); | ||
178 | oldcrithyst = data->temp_crit - data->temp_hyst; | ||
179 | data->temp_crit = val; | ||
180 | data->temp_hyst = data->temp_crit - oldcrithyst; | ||
181 | lm77_write_value(client, LM77_REG_TEMP_CRIT, | ||
182 | LM77_TEMP_TO_REG(data->temp_crit)); | ||
183 | lm77_write_value(client, LM77_REG_TEMP_HYST, | ||
184 | LM77_TEMP_TO_REG(data->temp_hyst)); | ||
185 | up(&data->update_lock); | ||
186 | return count; | ||
187 | } | ||
188 | |||
189 | static DEVICE_ATTR(temp1_input, S_IRUGO, | ||
190 | show_temp_input, NULL); | ||
191 | static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, | ||
192 | show_temp_crit, set_temp_crit); | ||
193 | static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, | ||
194 | show_temp_min, set_temp_min); | ||
195 | static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, | ||
196 | show_temp_max, set_temp_max); | ||
197 | |||
198 | static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, | ||
199 | show_temp_crit_hyst, set_temp_crit_hyst); | ||
200 | static DEVICE_ATTR(temp1_min_hyst, S_IRUGO, | ||
201 | show_temp_min_hyst, NULL); | ||
202 | static DEVICE_ATTR(temp1_max_hyst, S_IRUGO, | ||
203 | show_temp_max_hyst, NULL); | ||
204 | |||
205 | static DEVICE_ATTR(alarms, S_IRUGO, | ||
206 | show_alarms, NULL); | ||
207 | |||
208 | static int lm77_attach_adapter(struct i2c_adapter *adapter) | ||
209 | { | ||
210 | if (!(adapter->class & I2C_CLASS_HWMON)) | ||
211 | return 0; | ||
212 | return i2c_detect(adapter, &addr_data, lm77_detect); | ||
213 | } | ||
214 | |||
215 | /* This function is called by i2c_detect */ | ||
216 | static int lm77_detect(struct i2c_adapter *adapter, int address, int kind) | ||
217 | { | ||
218 | struct i2c_client *new_client; | ||
219 | struct lm77_data *data; | ||
220 | int err = 0; | ||
221 | const char *name = ""; | ||
222 | |||
223 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | | ||
224 | I2C_FUNC_SMBUS_WORD_DATA)) | ||
225 | goto exit; | ||
226 | |||
227 | /* OK. For now, we presume we have a valid client. We now create the | ||
228 | client structure, even though we cannot fill it completely yet. | ||
229 | But it allows us to access lm77_{read,write}_value. */ | ||
230 | if (!(data = kmalloc(sizeof(struct lm77_data), GFP_KERNEL))) { | ||
231 | err = -ENOMEM; | ||
232 | goto exit; | ||
233 | } | ||
234 | memset(data, 0, sizeof(struct lm77_data)); | ||
235 | |||
236 | new_client = &data->client; | ||
237 | i2c_set_clientdata(new_client, data); | ||
238 | new_client->addr = address; | ||
239 | new_client->adapter = adapter; | ||
240 | new_client->driver = &lm77_driver; | ||
241 | new_client->flags = 0; | ||
242 | |||
243 | /* Here comes the remaining detection. Since the LM77 has no | ||
244 | register dedicated to identification, we have to rely on the | ||
245 | following tricks: | ||
246 | |||
247 | 1. the high 4 bits represent the sign and thus they should | ||
248 | always be the same | ||
249 | 2. the high 3 bits are unused in the configuration register | ||
250 | 3. addresses 0x06 and 0x07 return the last read value | ||
251 | 4. registers cycling over 8-address boundaries | ||
252 | |||
253 | Word-sized registers are high-byte first. */ | ||
254 | if (kind < 0) { | ||
255 | int i, cur, conf, hyst, crit, min, max; | ||
256 | |||
257 | /* addresses cycling */ | ||
258 | cur = i2c_smbus_read_word_data(new_client, 0); | ||
259 | conf = i2c_smbus_read_byte_data(new_client, 1); | ||
260 | hyst = i2c_smbus_read_word_data(new_client, 2); | ||
261 | crit = i2c_smbus_read_word_data(new_client, 3); | ||
262 | min = i2c_smbus_read_word_data(new_client, 4); | ||
263 | max = i2c_smbus_read_word_data(new_client, 5); | ||
264 | for (i = 8; i <= 0xff; i += 8) | ||
265 | if (i2c_smbus_read_byte_data(new_client, i + 1) != conf | ||
266 | || i2c_smbus_read_word_data(new_client, i + 2) != hyst | ||
267 | || i2c_smbus_read_word_data(new_client, i + 3) != crit | ||
268 | || i2c_smbus_read_word_data(new_client, i + 4) != min | ||
269 | || i2c_smbus_read_word_data(new_client, i + 5) != max) | ||
270 | goto exit_free; | ||
271 | |||
272 | /* sign bits */ | ||
273 | if (((cur & 0x00f0) != 0xf0 && (cur & 0x00f0) != 0x0) | ||
274 | || ((hyst & 0x00f0) != 0xf0 && (hyst & 0x00f0) != 0x0) | ||
275 | || ((crit & 0x00f0) != 0xf0 && (crit & 0x00f0) != 0x0) | ||
276 | || ((min & 0x00f0) != 0xf0 && (min & 0x00f0) != 0x0) | ||
277 | || ((max & 0x00f0) != 0xf0 && (max & 0x00f0) != 0x0)) | ||
278 | goto exit_free; | ||
279 | |||
280 | /* unused bits */ | ||
281 | if (conf & 0xe0) | ||
282 | goto exit_free; | ||
283 | |||
284 | /* 0x06 and 0x07 return the last read value */ | ||
285 | cur = i2c_smbus_read_word_data(new_client, 0); | ||
286 | if (i2c_smbus_read_word_data(new_client, 6) != cur | ||
287 | || i2c_smbus_read_word_data(new_client, 7) != cur) | ||
288 | goto exit_free; | ||
289 | hyst = i2c_smbus_read_word_data(new_client, 2); | ||
290 | if (i2c_smbus_read_word_data(new_client, 6) != hyst | ||
291 | || i2c_smbus_read_word_data(new_client, 7) != hyst) | ||
292 | goto exit_free; | ||
293 | min = i2c_smbus_read_word_data(new_client, 4); | ||
294 | if (i2c_smbus_read_word_data(new_client, 6) != min | ||
295 | || i2c_smbus_read_word_data(new_client, 7) != min) | ||
296 | goto exit_free; | ||
297 | |||
298 | } | ||
299 | |||
300 | /* Determine the chip type - only one kind supported! */ | ||
301 | if (kind <= 0) | ||
302 | kind = lm77; | ||
303 | |||
304 | if (kind == lm77) { | ||
305 | name = "lm77"; | ||
306 | } | ||
307 | |||
308 | /* Fill in the remaining client fields and put it into the global list */ | ||
309 | strlcpy(new_client->name, name, I2C_NAME_SIZE); | ||
310 | data->valid = 0; | ||
311 | init_MUTEX(&data->update_lock); | ||
312 | |||
313 | /* Tell the I2C layer a new client has arrived */ | ||
314 | if ((err = i2c_attach_client(new_client))) | ||
315 | goto exit_free; | ||
316 | |||
317 | /* Initialize the LM77 chip */ | ||
318 | lm77_init_client(new_client); | ||
319 | |||
320 | /* Register sysfs hooks */ | ||
321 | device_create_file(&new_client->dev, &dev_attr_temp1_input); | ||
322 | device_create_file(&new_client->dev, &dev_attr_temp1_crit); | ||
323 | device_create_file(&new_client->dev, &dev_attr_temp1_min); | ||
324 | device_create_file(&new_client->dev, &dev_attr_temp1_max); | ||
325 | device_create_file(&new_client->dev, &dev_attr_temp1_crit_hyst); | ||
326 | device_create_file(&new_client->dev, &dev_attr_temp1_min_hyst); | ||
327 | device_create_file(&new_client->dev, &dev_attr_temp1_max_hyst); | ||
328 | device_create_file(&new_client->dev, &dev_attr_alarms); | ||
329 | return 0; | ||
330 | |||
331 | exit_free: | ||
332 | kfree(data); | ||
333 | exit: | ||
334 | return err; | ||
335 | } | ||
336 | |||
337 | static int lm77_detach_client(struct i2c_client *client) | ||
338 | { | ||
339 | i2c_detach_client(client); | ||
340 | kfree(i2c_get_clientdata(client)); | ||
341 | return 0; | ||
342 | } | ||
343 | |||
344 | /* All registers are word-sized, except for the configuration register. | ||
345 | The LM77 uses the high-byte first convention. */ | ||
346 | static u16 lm77_read_value(struct i2c_client *client, u8 reg) | ||
347 | { | ||
348 | if (reg == LM77_REG_CONF) | ||
349 | return i2c_smbus_read_byte_data(client, reg); | ||
350 | else | ||
351 | return swab16(i2c_smbus_read_word_data(client, reg)); | ||
352 | } | ||
353 | |||
354 | static int lm77_write_value(struct i2c_client *client, u8 reg, u16 value) | ||
355 | { | ||
356 | if (reg == LM77_REG_CONF) | ||
357 | return i2c_smbus_write_byte_data(client, reg, value); | ||
358 | else | ||
359 | return i2c_smbus_write_word_data(client, reg, swab16(value)); | ||
360 | } | ||
361 | |||
362 | static void lm77_init_client(struct i2c_client *client) | ||
363 | { | ||
364 | /* Initialize the LM77 chip - turn off shutdown mode */ | ||
365 | int conf = lm77_read_value(client, LM77_REG_CONF); | ||
366 | if (conf & 1) | ||
367 | lm77_write_value(client, LM77_REG_CONF, conf & 0xfe); | ||
368 | } | ||
369 | |||
370 | static struct lm77_data *lm77_update_device(struct device *dev) | ||
371 | { | ||
372 | struct i2c_client *client = to_i2c_client(dev); | ||
373 | struct lm77_data *data = i2c_get_clientdata(client); | ||
374 | |||
375 | down(&data->update_lock); | ||
376 | |||
377 | if (time_after(jiffies, data->last_updated + HZ + HZ / 2) | ||
378 | || !data->valid) { | ||
379 | dev_dbg(&client->dev, "Starting lm77 update\n"); | ||
380 | data->temp_input = | ||
381 | LM77_TEMP_FROM_REG(lm77_read_value(client, | ||
382 | LM77_REG_TEMP)); | ||
383 | data->temp_hyst = | ||
384 | LM77_TEMP_FROM_REG(lm77_read_value(client, | ||
385 | LM77_REG_TEMP_HYST)); | ||
386 | data->temp_crit = | ||
387 | LM77_TEMP_FROM_REG(lm77_read_value(client, | ||
388 | LM77_REG_TEMP_CRIT)); | ||
389 | data->temp_min = | ||
390 | LM77_TEMP_FROM_REG(lm77_read_value(client, | ||
391 | LM77_REG_TEMP_MIN)); | ||
392 | data->temp_max = | ||
393 | LM77_TEMP_FROM_REG(lm77_read_value(client, | ||
394 | LM77_REG_TEMP_MAX)); | ||
395 | data->alarms = | ||
396 | lm77_read_value(client, LM77_REG_TEMP) & 0x0007; | ||
397 | data->last_updated = jiffies; | ||
398 | data->valid = 1; | ||
399 | } | ||
400 | |||
401 | up(&data->update_lock); | ||
402 | |||
403 | return data; | ||
404 | } | ||
405 | |||
406 | static int __init sensors_lm77_init(void) | ||
407 | { | ||
408 | return i2c_add_driver(&lm77_driver); | ||
409 | } | ||
410 | |||
411 | static void __exit sensors_lm77_exit(void) | ||
412 | { | ||
413 | i2c_del_driver(&lm77_driver); | ||
414 | } | ||
415 | |||
416 | MODULE_AUTHOR("Andras BALI <drewie@freemail.hu>"); | ||
417 | MODULE_DESCRIPTION("LM77 driver"); | ||
418 | MODULE_LICENSE("GPL"); | ||
419 | |||
420 | module_init(sensors_lm77_init); | ||
421 | module_exit(sensors_lm77_exit); | ||