xref: /linux/drivers/hwmon/max1619.c (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
1 /*
2  * max1619.c - Part of lm_sensors, Linux kernel modules for hardware
3  *             monitoring
4  * Copyright (C) 2003-2004 Alexey Fisher <fishor@mail.ru>
5  *                         Jean Delvare <khali@linux-fr.org>
6  *
7  * Based on the lm90 driver. The MAX1619 is a sensor chip made by Maxim.
8  * It reports up to two temperatures (its own plus up to
9  * one external one). Complete datasheet can be
10  * obtained from Maxim's website at:
11  *   http://pdfserv.maxim-ic.com/en/ds/MAX1619.pdf
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 
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/hwmon.h>
35 #include <linux/hwmon-sysfs.h>
36 #include <linux/err.h>
37 #include <linux/mutex.h>
38 #include <linux/sysfs.h>
39 
40 static const unsigned short normal_i2c[] = {
41 	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
42 
43 /*
44  * Insmod parameters
45  */
46 
47 I2C_CLIENT_INSMOD_1(max1619);
48 
49 /*
50  * The MAX1619 registers
51  */
52 
53 #define MAX1619_REG_R_MAN_ID		0xFE
54 #define MAX1619_REG_R_CHIP_ID		0xFF
55 #define MAX1619_REG_R_CONFIG		0x03
56 #define MAX1619_REG_W_CONFIG		0x09
57 #define MAX1619_REG_R_CONVRATE		0x04
58 #define MAX1619_REG_W_CONVRATE		0x0A
59 #define MAX1619_REG_R_STATUS		0x02
60 #define MAX1619_REG_R_LOCAL_TEMP	0x00
61 #define MAX1619_REG_R_REMOTE_TEMP	0x01
62 #define MAX1619_REG_R_REMOTE_HIGH	0x07
63 #define MAX1619_REG_W_REMOTE_HIGH	0x0D
64 #define MAX1619_REG_R_REMOTE_LOW	0x08
65 #define MAX1619_REG_W_REMOTE_LOW	0x0E
66 #define MAX1619_REG_R_REMOTE_CRIT	0x10
67 #define MAX1619_REG_W_REMOTE_CRIT	0x12
68 #define MAX1619_REG_R_TCRIT_HYST	0x11
69 #define MAX1619_REG_W_TCRIT_HYST	0x13
70 
71 /*
72  * Conversions
73  */
74 
75 static int temp_from_reg(int val)
76 {
77 	return (val & 0x80 ? val-0x100 : val) * 1000;
78 }
79 
80 static int temp_to_reg(int val)
81 {
82 	return (val < 0 ? val+0x100*1000 : val) / 1000;
83 }
84 
85 /*
86  * Functions declaration
87  */
88 
89 static int max1619_probe(struct i2c_client *client,
90 			 const struct i2c_device_id *id);
91 static int max1619_detect(struct i2c_client *client, int kind,
92 			  struct i2c_board_info *info);
93 static void max1619_init_client(struct i2c_client *client);
94 static int max1619_remove(struct i2c_client *client);
95 static struct max1619_data *max1619_update_device(struct device *dev);
96 
97 /*
98  * Driver data (common to all clients)
99  */
100 
101 static const struct i2c_device_id max1619_id[] = {
102 	{ "max1619", max1619 },
103 	{ }
104 };
105 MODULE_DEVICE_TABLE(i2c, max1619_id);
106 
107 static struct i2c_driver max1619_driver = {
108 	.class		= I2C_CLASS_HWMON,
109 	.driver = {
110 		.name	= "max1619",
111 	},
112 	.probe		= max1619_probe,
113 	.remove		= max1619_remove,
114 	.id_table	= max1619_id,
115 	.detect		= max1619_detect,
116 	.address_data	= &addr_data,
117 };
118 
119 /*
120  * Client data (each client gets its own)
121  */
122 
123 struct max1619_data {
124 	struct device *hwmon_dev;
125 	struct mutex update_lock;
126 	char valid; /* zero until following fields are valid */
127 	unsigned long last_updated; /* in jiffies */
128 
129 	/* registers values */
130 	u8 temp_input1; /* local */
131 	u8 temp_input2, temp_low2, temp_high2; /* remote */
132 	u8 temp_crit2;
133 	u8 temp_hyst2;
134 	u8 alarms;
135 };
136 
137 /*
138  * Sysfs stuff
139  */
140 
141 #define show_temp(value) \
142 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
143 { \
144 	struct max1619_data *data = max1619_update_device(dev); \
145 	return sprintf(buf, "%d\n", temp_from_reg(data->value)); \
146 }
147 show_temp(temp_input1);
148 show_temp(temp_input2);
149 show_temp(temp_low2);
150 show_temp(temp_high2);
151 show_temp(temp_crit2);
152 show_temp(temp_hyst2);
153 
154 #define set_temp2(value, reg) \
155 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
156 	size_t count) \
157 { \
158 	struct i2c_client *client = to_i2c_client(dev); \
159 	struct max1619_data *data = i2c_get_clientdata(client); \
160 	long val = simple_strtol(buf, NULL, 10); \
161  \
162 	mutex_lock(&data->update_lock); \
163 	data->value = temp_to_reg(val); \
164 	i2c_smbus_write_byte_data(client, reg, data->value); \
165 	mutex_unlock(&data->update_lock); \
166 	return count; \
167 }
168 
169 set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
170 set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
171 set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
172 set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
173 
174 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
175 {
176 	struct max1619_data *data = max1619_update_device(dev);
177 	return sprintf(buf, "%d\n", data->alarms);
178 }
179 
180 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
181 			  char *buf)
182 {
183 	int bitnr = to_sensor_dev_attr(attr)->index;
184 	struct max1619_data *data = max1619_update_device(dev);
185 	return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
186 }
187 
188 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
189 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
190 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
191 	set_temp_low2);
192 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
193 	set_temp_high2);
194 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
195 	set_temp_crit2);
196 static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
197 	set_temp_hyst2);
198 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
199 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
200 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
201 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
202 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
203 
204 static struct attribute *max1619_attributes[] = {
205 	&dev_attr_temp1_input.attr,
206 	&dev_attr_temp2_input.attr,
207 	&dev_attr_temp2_min.attr,
208 	&dev_attr_temp2_max.attr,
209 	&dev_attr_temp2_crit.attr,
210 	&dev_attr_temp2_crit_hyst.attr,
211 
212 	&dev_attr_alarms.attr,
213 	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
214 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
215 	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
216 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
217 	NULL
218 };
219 
220 static const struct attribute_group max1619_group = {
221 	.attrs = max1619_attributes,
222 };
223 
224 /*
225  * Real code
226  */
227 
228 /* Return 0 if detection is successful, -ENODEV otherwise */
229 static int max1619_detect(struct i2c_client *new_client, int kind,
230 			  struct i2c_board_info *info)
231 {
232 	struct i2c_adapter *adapter = new_client->adapter;
233 	u8 reg_config=0, reg_convrate=0, reg_status=0;
234 
235 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
236 		return -ENODEV;
237 
238 	/*
239 	 * Now we do the remaining detection. A negative kind means that
240 	 * the driver was loaded with no force parameter (default), so we
241 	 * must both detect and identify the chip. A zero kind means that
242 	 * the driver was loaded with the force parameter, the detection
243 	 * step shall be skipped. A positive kind means that the driver
244 	 * was loaded with the force parameter and a given kind of chip is
245 	 * requested, so both the detection and the identification steps
246 	 * are skipped.
247 	 */
248 	if (kind < 0) { /* detection */
249 		reg_config = i2c_smbus_read_byte_data(new_client,
250 			      MAX1619_REG_R_CONFIG);
251 		reg_convrate = i2c_smbus_read_byte_data(new_client,
252 			       MAX1619_REG_R_CONVRATE);
253 		reg_status = i2c_smbus_read_byte_data(new_client,
254 				MAX1619_REG_R_STATUS);
255 		if ((reg_config & 0x03) != 0x00
256 		 || reg_convrate > 0x07 || (reg_status & 0x61 ) !=0x00) {
257 			dev_dbg(&adapter->dev,
258 				"MAX1619 detection failed at 0x%02x.\n",
259 				new_client->addr);
260 			return -ENODEV;
261 		}
262 	}
263 
264 	if (kind <= 0) { /* identification */
265 		u8 man_id, chip_id;
266 
267 		man_id = i2c_smbus_read_byte_data(new_client,
268 			 MAX1619_REG_R_MAN_ID);
269 		chip_id = i2c_smbus_read_byte_data(new_client,
270 			  MAX1619_REG_R_CHIP_ID);
271 
272 		if ((man_id == 0x4D) && (chip_id == 0x04))
273 			kind = max1619;
274 
275 		if (kind <= 0) { /* identification failed */
276 			dev_info(&adapter->dev,
277 			    "Unsupported chip (man_id=0x%02X, "
278 			    "chip_id=0x%02X).\n", man_id, chip_id);
279 			return -ENODEV;
280 		}
281 	}
282 
283 	strlcpy(info->type, "max1619", I2C_NAME_SIZE);
284 
285 	return 0;
286 }
287 
288 static int max1619_probe(struct i2c_client *new_client,
289 			 const struct i2c_device_id *id)
290 {
291 	struct max1619_data *data;
292 	int err;
293 
294 	data = kzalloc(sizeof(struct max1619_data), GFP_KERNEL);
295 	if (!data) {
296 		err = -ENOMEM;
297 		goto exit;
298 	}
299 
300 	i2c_set_clientdata(new_client, data);
301 	data->valid = 0;
302 	mutex_init(&data->update_lock);
303 
304 	/* Initialize the MAX1619 chip */
305 	max1619_init_client(new_client);
306 
307 	/* Register sysfs hooks */
308 	if ((err = sysfs_create_group(&new_client->dev.kobj, &max1619_group)))
309 		goto exit_free;
310 
311 	data->hwmon_dev = hwmon_device_register(&new_client->dev);
312 	if (IS_ERR(data->hwmon_dev)) {
313 		err = PTR_ERR(data->hwmon_dev);
314 		goto exit_remove_files;
315 	}
316 
317 	return 0;
318 
319 exit_remove_files:
320 	sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
321 exit_free:
322 	kfree(data);
323 exit:
324 	return err;
325 }
326 
327 static void max1619_init_client(struct i2c_client *client)
328 {
329 	u8 config;
330 
331 	/*
332 	 * Start the conversions.
333 	 */
334 	i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
335 				  5); /* 2 Hz */
336 	config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
337 	if (config & 0x40)
338 		i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
339 					  config & 0xBF); /* run */
340 }
341 
342 static int max1619_remove(struct i2c_client *client)
343 {
344 	struct max1619_data *data = i2c_get_clientdata(client);
345 
346 	hwmon_device_unregister(data->hwmon_dev);
347 	sysfs_remove_group(&client->dev.kobj, &max1619_group);
348 
349 	kfree(data);
350 	return 0;
351 }
352 
353 static struct max1619_data *max1619_update_device(struct device *dev)
354 {
355 	struct i2c_client *client = to_i2c_client(dev);
356 	struct max1619_data *data = i2c_get_clientdata(client);
357 
358 	mutex_lock(&data->update_lock);
359 
360 	if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
361 		dev_dbg(&client->dev, "Updating max1619 data.\n");
362 		data->temp_input1 = i2c_smbus_read_byte_data(client,
363 					MAX1619_REG_R_LOCAL_TEMP);
364 		data->temp_input2 = i2c_smbus_read_byte_data(client,
365 					MAX1619_REG_R_REMOTE_TEMP);
366 		data->temp_high2 = i2c_smbus_read_byte_data(client,
367 					MAX1619_REG_R_REMOTE_HIGH);
368 		data->temp_low2 = i2c_smbus_read_byte_data(client,
369 					MAX1619_REG_R_REMOTE_LOW);
370 		data->temp_crit2 = i2c_smbus_read_byte_data(client,
371 					MAX1619_REG_R_REMOTE_CRIT);
372 		data->temp_hyst2 = i2c_smbus_read_byte_data(client,
373 					MAX1619_REG_R_TCRIT_HYST);
374 		data->alarms = i2c_smbus_read_byte_data(client,
375 					MAX1619_REG_R_STATUS);
376 
377 		data->last_updated = jiffies;
378 		data->valid = 1;
379 	}
380 
381 	mutex_unlock(&data->update_lock);
382 
383 	return data;
384 }
385 
386 static int __init sensors_max1619_init(void)
387 {
388 	return i2c_add_driver(&max1619_driver);
389 }
390 
391 static void __exit sensors_max1619_exit(void)
392 {
393 	i2c_del_driver(&max1619_driver);
394 }
395 
396 MODULE_AUTHOR("Alexey Fisher <fishor@mail.ru> and "
397 	"Jean Delvare <khali@linux-fr.org>");
398 MODULE_DESCRIPTION("MAX1619 sensor driver");
399 MODULE_LICENSE("GPL");
400 
401 module_init(sensors_max1619_init);
402 module_exit(sensors_max1619_exit);
403