diff options
author | Glenn Elliott <gelliott@cs.unc.edu> | 2012-03-04 19:47:13 -0500 |
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committer | Glenn Elliott <gelliott@cs.unc.edu> | 2012-03-04 19:47:13 -0500 |
commit | c71c03bda1e86c9d5198c5d83f712e695c4f2a1e (patch) | |
tree | ecb166cb3e2b7e2adb3b5e292245fefd23381ac8 /drivers/hwmon/max6642.c | |
parent | ea53c912f8a86a8567697115b6a0d8152beee5c8 (diff) | |
parent | 6a00f206debf8a5c8899055726ad127dbeeed098 (diff) |
Merge branch 'mpi-master' into wip-k-fmlpwip-k-fmlp
Conflicts:
litmus/sched_cedf.c
Diffstat (limited to 'drivers/hwmon/max6642.c')
-rw-r--r-- | drivers/hwmon/max6642.c | 370 |
1 files changed, 370 insertions, 0 deletions
diff --git a/drivers/hwmon/max6642.c b/drivers/hwmon/max6642.c new file mode 100644 index 000000000000..e855d3b0bd1f --- /dev/null +++ b/drivers/hwmon/max6642.c | |||
@@ -0,0 +1,370 @@ | |||
1 | /* | ||
2 | * Driver for +/-1 degree C, SMBus-Compatible Remote/Local Temperature Sensor | ||
3 | * with Overtemperature Alarm | ||
4 | * | ||
5 | * Copyright (C) 2011 AppearTV AS | ||
6 | * | ||
7 | * Derived from: | ||
8 | * | ||
9 | * Based on the max1619 driver. | ||
10 | * Copyright (C) 2003-2004 Alexey Fisher <fishor@mail.ru> | ||
11 | * Jean Delvare <khali@linux-fr.org> | ||
12 | * | ||
13 | * The MAX6642 is a sensor chip made by Maxim. | ||
14 | * It reports up to two temperatures (its own plus up to | ||
15 | * one external one). Complete datasheet can be | ||
16 | * obtained from Maxim's website at: | ||
17 | * http://datasheets.maxim-ic.com/en/ds/MAX6642.pdf | ||
18 | * | ||
19 | * This program is free software; you can redistribute it and/or modify | ||
20 | * it under the terms of the GNU General Public License as published by | ||
21 | * the Free Software Foundation; either version 2 of the License, or | ||
22 | * (at your option) any later version. | ||
23 | * | ||
24 | * This program is distributed in the hope that it will be useful, | ||
25 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
26 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
27 | * GNU General Public License for more details. | ||
28 | * | ||
29 | * You should have received a copy of the GNU General Public License | ||
30 | * along with this program; if not, write to the Free Software | ||
31 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | ||
32 | */ | ||
33 | |||
34 | |||
35 | #include <linux/module.h> | ||
36 | #include <linux/init.h> | ||
37 | #include <linux/slab.h> | ||
38 | #include <linux/jiffies.h> | ||
39 | #include <linux/i2c.h> | ||
40 | #include <linux/hwmon.h> | ||
41 | #include <linux/hwmon-sysfs.h> | ||
42 | #include <linux/err.h> | ||
43 | #include <linux/mutex.h> | ||
44 | #include <linux/sysfs.h> | ||
45 | |||
46 | static const unsigned short normal_i2c[] = { | ||
47 | 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, I2C_CLIENT_END }; | ||
48 | |||
49 | /* | ||
50 | * The MAX6642 registers | ||
51 | */ | ||
52 | |||
53 | #define MAX6642_REG_R_MAN_ID 0xFE | ||
54 | #define MAX6642_REG_R_CONFIG 0x03 | ||
55 | #define MAX6642_REG_W_CONFIG 0x09 | ||
56 | #define MAX6642_REG_R_STATUS 0x02 | ||
57 | #define MAX6642_REG_R_LOCAL_TEMP 0x00 | ||
58 | #define MAX6642_REG_R_LOCAL_TEMPL 0x11 | ||
59 | #define MAX6642_REG_R_LOCAL_HIGH 0x05 | ||
60 | #define MAX6642_REG_W_LOCAL_HIGH 0x0B | ||
61 | #define MAX6642_REG_R_REMOTE_TEMP 0x01 | ||
62 | #define MAX6642_REG_R_REMOTE_TEMPL 0x10 | ||
63 | #define MAX6642_REG_R_REMOTE_HIGH 0x07 | ||
64 | #define MAX6642_REG_W_REMOTE_HIGH 0x0D | ||
65 | |||
66 | /* | ||
67 | * Conversions | ||
68 | */ | ||
69 | |||
70 | static int temp_from_reg10(int val) | ||
71 | { | ||
72 | return val * 250; | ||
73 | } | ||
74 | |||
75 | static int temp_from_reg(int val) | ||
76 | { | ||
77 | return val * 1000; | ||
78 | } | ||
79 | |||
80 | static int temp_to_reg(int val) | ||
81 | { | ||
82 | return val / 1000; | ||
83 | } | ||
84 | |||
85 | /* | ||
86 | * Client data (each client gets its own) | ||
87 | */ | ||
88 | |||
89 | struct max6642_data { | ||
90 | struct device *hwmon_dev; | ||
91 | struct mutex update_lock; | ||
92 | bool valid; /* zero until following fields are valid */ | ||
93 | unsigned long last_updated; /* in jiffies */ | ||
94 | |||
95 | /* registers values */ | ||
96 | u16 temp_input[2]; /* local/remote */ | ||
97 | u16 temp_high[2]; /* local/remote */ | ||
98 | u8 alarms; | ||
99 | }; | ||
100 | |||
101 | /* | ||
102 | * Real code | ||
103 | */ | ||
104 | |||
105 | static void max6642_init_client(struct i2c_client *client) | ||
106 | { | ||
107 | u8 config; | ||
108 | struct max6642_data *data = i2c_get_clientdata(client); | ||
109 | |||
110 | /* | ||
111 | * Start the conversions. | ||
112 | */ | ||
113 | config = i2c_smbus_read_byte_data(client, MAX6642_REG_R_CONFIG); | ||
114 | if (config & 0x40) | ||
115 | i2c_smbus_write_byte_data(client, MAX6642_REG_W_CONFIG, | ||
116 | config & 0xBF); /* run */ | ||
117 | |||
118 | data->temp_high[0] = i2c_smbus_read_byte_data(client, | ||
119 | MAX6642_REG_R_LOCAL_HIGH); | ||
120 | data->temp_high[1] = i2c_smbus_read_byte_data(client, | ||
121 | MAX6642_REG_R_REMOTE_HIGH); | ||
122 | } | ||
123 | |||
124 | /* Return 0 if detection is successful, -ENODEV otherwise */ | ||
125 | static int max6642_detect(struct i2c_client *client, | ||
126 | struct i2c_board_info *info) | ||
127 | { | ||
128 | struct i2c_adapter *adapter = client->adapter; | ||
129 | u8 reg_config, reg_status, man_id; | ||
130 | |||
131 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) | ||
132 | return -ENODEV; | ||
133 | |||
134 | /* identification */ | ||
135 | man_id = i2c_smbus_read_byte_data(client, MAX6642_REG_R_MAN_ID); | ||
136 | if (man_id != 0x4D) | ||
137 | return -ENODEV; | ||
138 | |||
139 | /* sanity check */ | ||
140 | if (i2c_smbus_read_byte_data(client, 0x04) != 0x4D | ||
141 | || i2c_smbus_read_byte_data(client, 0x06) != 0x4D | ||
142 | || i2c_smbus_read_byte_data(client, 0xff) != 0x4D) | ||
143 | return -ENODEV; | ||
144 | |||
145 | /* | ||
146 | * We read the config and status register, the 4 lower bits in the | ||
147 | * config register should be zero and bit 5, 3, 1 and 0 should be | ||
148 | * zero in the status register. | ||
149 | */ | ||
150 | reg_config = i2c_smbus_read_byte_data(client, MAX6642_REG_R_CONFIG); | ||
151 | if ((reg_config & 0x0f) != 0x00) | ||
152 | return -ENODEV; | ||
153 | |||
154 | /* in between, another round of sanity checks */ | ||
155 | if (i2c_smbus_read_byte_data(client, 0x04) != reg_config | ||
156 | || i2c_smbus_read_byte_data(client, 0x06) != reg_config | ||
157 | || i2c_smbus_read_byte_data(client, 0xff) != reg_config) | ||
158 | return -ENODEV; | ||
159 | |||
160 | reg_status = i2c_smbus_read_byte_data(client, MAX6642_REG_R_STATUS); | ||
161 | if ((reg_status & 0x2b) != 0x00) | ||
162 | return -ENODEV; | ||
163 | |||
164 | strlcpy(info->type, "max6642", I2C_NAME_SIZE); | ||
165 | |||
166 | return 0; | ||
167 | } | ||
168 | |||
169 | static struct max6642_data *max6642_update_device(struct device *dev) | ||
170 | { | ||
171 | struct i2c_client *client = to_i2c_client(dev); | ||
172 | struct max6642_data *data = i2c_get_clientdata(client); | ||
173 | u16 val, tmp; | ||
174 | |||
175 | mutex_lock(&data->update_lock); | ||
176 | |||
177 | if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { | ||
178 | dev_dbg(&client->dev, "Updating max6642 data.\n"); | ||
179 | val = i2c_smbus_read_byte_data(client, | ||
180 | MAX6642_REG_R_LOCAL_TEMPL); | ||
181 | tmp = (val >> 6) & 3; | ||
182 | val = i2c_smbus_read_byte_data(client, | ||
183 | MAX6642_REG_R_LOCAL_TEMP); | ||
184 | val = (val << 2) | tmp; | ||
185 | data->temp_input[0] = val; | ||
186 | val = i2c_smbus_read_byte_data(client, | ||
187 | MAX6642_REG_R_REMOTE_TEMPL); | ||
188 | tmp = (val >> 6) & 3; | ||
189 | val = i2c_smbus_read_byte_data(client, | ||
190 | MAX6642_REG_R_REMOTE_TEMP); | ||
191 | val = (val << 2) | tmp; | ||
192 | data->temp_input[1] = val; | ||
193 | data->alarms = i2c_smbus_read_byte_data(client, | ||
194 | MAX6642_REG_R_STATUS); | ||
195 | |||
196 | data->last_updated = jiffies; | ||
197 | data->valid = 1; | ||
198 | } | ||
199 | |||
200 | mutex_unlock(&data->update_lock); | ||
201 | |||
202 | return data; | ||
203 | } | ||
204 | |||
205 | /* | ||
206 | * Sysfs stuff | ||
207 | */ | ||
208 | |||
209 | static ssize_t show_temp_max10(struct device *dev, | ||
210 | struct device_attribute *dev_attr, char *buf) | ||
211 | { | ||
212 | struct max6642_data *data = max6642_update_device(dev); | ||
213 | struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); | ||
214 | |||
215 | return sprintf(buf, "%d\n", | ||
216 | temp_from_reg10(data->temp_input[attr->index])); | ||
217 | } | ||
218 | |||
219 | static ssize_t show_temp_max(struct device *dev, struct device_attribute *attr, | ||
220 | char *buf) | ||
221 | { | ||
222 | struct max6642_data *data = max6642_update_device(dev); | ||
223 | struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr); | ||
224 | |||
225 | return sprintf(buf, "%d\n", temp_from_reg(data->temp_high[attr2->nr])); | ||
226 | } | ||
227 | |||
228 | static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr, | ||
229 | const char *buf, size_t count) | ||
230 | { | ||
231 | unsigned long val; | ||
232 | int err; | ||
233 | struct i2c_client *client = to_i2c_client(dev); | ||
234 | struct max6642_data *data = i2c_get_clientdata(client); | ||
235 | struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr); | ||
236 | |||
237 | err = strict_strtoul(buf, 10, &val); | ||
238 | if (err < 0) | ||
239 | return err; | ||
240 | |||
241 | mutex_lock(&data->update_lock); | ||
242 | data->temp_high[attr2->nr] = SENSORS_LIMIT(temp_to_reg(val), 0, 255); | ||
243 | i2c_smbus_write_byte_data(client, attr2->index, | ||
244 | data->temp_high[attr2->nr]); | ||
245 | mutex_unlock(&data->update_lock); | ||
246 | return count; | ||
247 | } | ||
248 | |||
249 | static ssize_t show_alarm(struct device *dev, struct device_attribute *attr, | ||
250 | char *buf) | ||
251 | { | ||
252 | int bitnr = to_sensor_dev_attr(attr)->index; | ||
253 | struct max6642_data *data = max6642_update_device(dev); | ||
254 | return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1); | ||
255 | } | ||
256 | |||
257 | static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_max10, NULL, 0); | ||
258 | static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_max10, NULL, 1); | ||
259 | static SENSOR_DEVICE_ATTR_2(temp1_max, S_IWUSR | S_IRUGO, show_temp_max, | ||
260 | set_temp_max, 0, MAX6642_REG_W_LOCAL_HIGH); | ||
261 | static SENSOR_DEVICE_ATTR_2(temp2_max, S_IWUSR | S_IRUGO, show_temp_max, | ||
262 | set_temp_max, 1, MAX6642_REG_W_REMOTE_HIGH); | ||
263 | static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2); | ||
264 | static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6); | ||
265 | static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4); | ||
266 | |||
267 | static struct attribute *max6642_attributes[] = { | ||
268 | &sensor_dev_attr_temp1_input.dev_attr.attr, | ||
269 | &sensor_dev_attr_temp2_input.dev_attr.attr, | ||
270 | &sensor_dev_attr_temp1_max.dev_attr.attr, | ||
271 | &sensor_dev_attr_temp2_max.dev_attr.attr, | ||
272 | |||
273 | &sensor_dev_attr_temp2_fault.dev_attr.attr, | ||
274 | &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, | ||
275 | &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, | ||
276 | NULL | ||
277 | }; | ||
278 | |||
279 | static const struct attribute_group max6642_group = { | ||
280 | .attrs = max6642_attributes, | ||
281 | }; | ||
282 | |||
283 | static int max6642_probe(struct i2c_client *new_client, | ||
284 | const struct i2c_device_id *id) | ||
285 | { | ||
286 | struct max6642_data *data; | ||
287 | int err; | ||
288 | |||
289 | data = kzalloc(sizeof(struct max6642_data), GFP_KERNEL); | ||
290 | if (!data) { | ||
291 | err = -ENOMEM; | ||
292 | goto exit; | ||
293 | } | ||
294 | |||
295 | i2c_set_clientdata(new_client, data); | ||
296 | mutex_init(&data->update_lock); | ||
297 | |||
298 | /* Initialize the MAX6642 chip */ | ||
299 | max6642_init_client(new_client); | ||
300 | |||
301 | /* Register sysfs hooks */ | ||
302 | err = sysfs_create_group(&new_client->dev.kobj, &max6642_group); | ||
303 | if (err) | ||
304 | goto exit_free; | ||
305 | |||
306 | data->hwmon_dev = hwmon_device_register(&new_client->dev); | ||
307 | if (IS_ERR(data->hwmon_dev)) { | ||
308 | err = PTR_ERR(data->hwmon_dev); | ||
309 | goto exit_remove_files; | ||
310 | } | ||
311 | |||
312 | return 0; | ||
313 | |||
314 | exit_remove_files: | ||
315 | sysfs_remove_group(&new_client->dev.kobj, &max6642_group); | ||
316 | exit_free: | ||
317 | kfree(data); | ||
318 | exit: | ||
319 | return err; | ||
320 | } | ||
321 | |||
322 | static int max6642_remove(struct i2c_client *client) | ||
323 | { | ||
324 | struct max6642_data *data = i2c_get_clientdata(client); | ||
325 | |||
326 | hwmon_device_unregister(data->hwmon_dev); | ||
327 | sysfs_remove_group(&client->dev.kobj, &max6642_group); | ||
328 | |||
329 | kfree(data); | ||
330 | return 0; | ||
331 | } | ||
332 | |||
333 | /* | ||
334 | * Driver data (common to all clients) | ||
335 | */ | ||
336 | |||
337 | static const struct i2c_device_id max6642_id[] = { | ||
338 | { "max6642", 0 }, | ||
339 | { } | ||
340 | }; | ||
341 | MODULE_DEVICE_TABLE(i2c, max6642_id); | ||
342 | |||
343 | static struct i2c_driver max6642_driver = { | ||
344 | .class = I2C_CLASS_HWMON, | ||
345 | .driver = { | ||
346 | .name = "max6642", | ||
347 | }, | ||
348 | .probe = max6642_probe, | ||
349 | .remove = max6642_remove, | ||
350 | .id_table = max6642_id, | ||
351 | .detect = max6642_detect, | ||
352 | .address_list = normal_i2c, | ||
353 | }; | ||
354 | |||
355 | static int __init max6642_init(void) | ||
356 | { | ||
357 | return i2c_add_driver(&max6642_driver); | ||
358 | } | ||
359 | |||
360 | static void __exit max6642_exit(void) | ||
361 | { | ||
362 | i2c_del_driver(&max6642_driver); | ||
363 | } | ||
364 | |||
365 | MODULE_AUTHOR("Per Dalen <per.dalen@appeartv.com>"); | ||
366 | MODULE_DESCRIPTION("MAX6642 sensor driver"); | ||
367 | MODULE_LICENSE("GPL"); | ||
368 | |||
369 | module_init(max6642_init); | ||
370 | module_exit(max6642_exit); | ||