xref: /openbmc/linux/drivers/hwmon/max1619.c (revision 384740dc)
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 and various macros
73  */
74 
75 #define TEMP_FROM_REG(val)	((val & 0x80 ? val-0x100 : val) * 1000)
76 #define TEMP_TO_REG(val)	((val < 0 ? val+0x100*1000 : val) / 1000)
77 
78 /*
79  * Functions declaration
80  */
81 
82 static int max1619_probe(struct i2c_client *client,
83 			 const struct i2c_device_id *id);
84 static int max1619_detect(struct i2c_client *client, int kind,
85 			  struct i2c_board_info *info);
86 static void max1619_init_client(struct i2c_client *client);
87 static int max1619_remove(struct i2c_client *client);
88 static struct max1619_data *max1619_update_device(struct device *dev);
89 
90 /*
91  * Driver data (common to all clients)
92  */
93 
94 static const struct i2c_device_id max1619_id[] = {
95 	{ "max1619", max1619 },
96 	{ }
97 };
98 MODULE_DEVICE_TABLE(i2c, max1619_id);
99 
100 static struct i2c_driver max1619_driver = {
101 	.class		= I2C_CLASS_HWMON,
102 	.driver = {
103 		.name	= "max1619",
104 	},
105 	.probe		= max1619_probe,
106 	.remove		= max1619_remove,
107 	.id_table	= max1619_id,
108 	.detect		= max1619_detect,
109 	.address_data	= &addr_data,
110 };
111 
112 /*
113  * Client data (each client gets its own)
114  */
115 
116 struct max1619_data {
117 	struct device *hwmon_dev;
118 	struct mutex update_lock;
119 	char valid; /* zero until following fields are valid */
120 	unsigned long last_updated; /* in jiffies */
121 
122 	/* registers values */
123 	u8 temp_input1; /* local */
124 	u8 temp_input2, temp_low2, temp_high2; /* remote */
125 	u8 temp_crit2;
126 	u8 temp_hyst2;
127 	u8 alarms;
128 };
129 
130 /*
131  * Sysfs stuff
132  */
133 
134 #define show_temp(value) \
135 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
136 { \
137 	struct max1619_data *data = max1619_update_device(dev); \
138 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->value)); \
139 }
140 show_temp(temp_input1);
141 show_temp(temp_input2);
142 show_temp(temp_low2);
143 show_temp(temp_high2);
144 show_temp(temp_crit2);
145 show_temp(temp_hyst2);
146 
147 #define set_temp2(value, reg) \
148 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
149 	size_t count) \
150 { \
151 	struct i2c_client *client = to_i2c_client(dev); \
152 	struct max1619_data *data = i2c_get_clientdata(client); \
153 	long val = simple_strtol(buf, NULL, 10); \
154  \
155 	mutex_lock(&data->update_lock); \
156 	data->value = TEMP_TO_REG(val); \
157 	i2c_smbus_write_byte_data(client, reg, data->value); \
158 	mutex_unlock(&data->update_lock); \
159 	return count; \
160 }
161 
162 set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
163 set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
164 set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
165 set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
166 
167 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
168 {
169 	struct max1619_data *data = max1619_update_device(dev);
170 	return sprintf(buf, "%d\n", data->alarms);
171 }
172 
173 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
174 			  char *buf)
175 {
176 	int bitnr = to_sensor_dev_attr(attr)->index;
177 	struct max1619_data *data = max1619_update_device(dev);
178 	return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
179 }
180 
181 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
182 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
183 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
184 	set_temp_low2);
185 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
186 	set_temp_high2);
187 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
188 	set_temp_crit2);
189 static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
190 	set_temp_hyst2);
191 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
192 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
193 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
194 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
195 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
196 
197 static struct attribute *max1619_attributes[] = {
198 	&dev_attr_temp1_input.attr,
199 	&dev_attr_temp2_input.attr,
200 	&dev_attr_temp2_min.attr,
201 	&dev_attr_temp2_max.attr,
202 	&dev_attr_temp2_crit.attr,
203 	&dev_attr_temp2_crit_hyst.attr,
204 
205 	&dev_attr_alarms.attr,
206 	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
207 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
208 	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
209 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
210 	NULL
211 };
212 
213 static const struct attribute_group max1619_group = {
214 	.attrs = max1619_attributes,
215 };
216 
217 /*
218  * Real code
219  */
220 
221 /* Return 0 if detection is successful, -ENODEV otherwise */
222 static int max1619_detect(struct i2c_client *new_client, int kind,
223 			  struct i2c_board_info *info)
224 {
225 	struct i2c_adapter *adapter = new_client->adapter;
226 	u8 reg_config=0, reg_convrate=0, reg_status=0;
227 
228 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
229 		return -ENODEV;
230 
231 	/*
232 	 * Now we do the remaining detection. A negative kind means that
233 	 * the driver was loaded with no force parameter (default), so we
234 	 * must both detect and identify the chip. A zero kind means that
235 	 * the driver was loaded with the force parameter, the detection
236 	 * step shall be skipped. A positive kind means that the driver
237 	 * was loaded with the force parameter and a given kind of chip is
238 	 * requested, so both the detection and the identification steps
239 	 * are skipped.
240 	 */
241 	if (kind < 0) { /* detection */
242 		reg_config = i2c_smbus_read_byte_data(new_client,
243 			      MAX1619_REG_R_CONFIG);
244 		reg_convrate = i2c_smbus_read_byte_data(new_client,
245 			       MAX1619_REG_R_CONVRATE);
246 		reg_status = i2c_smbus_read_byte_data(new_client,
247 				MAX1619_REG_R_STATUS);
248 		if ((reg_config & 0x03) != 0x00
249 		 || reg_convrate > 0x07 || (reg_status & 0x61 ) !=0x00) {
250 			dev_dbg(&adapter->dev,
251 				"MAX1619 detection failed at 0x%02x.\n",
252 				new_client->addr);
253 			return -ENODEV;
254 		}
255 	}
256 
257 	if (kind <= 0) { /* identification */
258 		u8 man_id, chip_id;
259 
260 		man_id = i2c_smbus_read_byte_data(new_client,
261 			 MAX1619_REG_R_MAN_ID);
262 		chip_id = i2c_smbus_read_byte_data(new_client,
263 			  MAX1619_REG_R_CHIP_ID);
264 
265 		if ((man_id == 0x4D) && (chip_id == 0x04))
266 			kind = max1619;
267 
268 		if (kind <= 0) { /* identification failed */
269 			dev_info(&adapter->dev,
270 			    "Unsupported chip (man_id=0x%02X, "
271 			    "chip_id=0x%02X).\n", man_id, chip_id);
272 			return -ENODEV;
273 		}
274 	}
275 
276 	strlcpy(info->type, "max1619", I2C_NAME_SIZE);
277 
278 	return 0;
279 }
280 
281 static int max1619_probe(struct i2c_client *new_client,
282 			 const struct i2c_device_id *id)
283 {
284 	struct max1619_data *data;
285 	int err;
286 
287 	data = kzalloc(sizeof(struct max1619_data), GFP_KERNEL);
288 	if (!data) {
289 		err = -ENOMEM;
290 		goto exit;
291 	}
292 
293 	i2c_set_clientdata(new_client, data);
294 	data->valid = 0;
295 	mutex_init(&data->update_lock);
296 
297 	/* Initialize the MAX1619 chip */
298 	max1619_init_client(new_client);
299 
300 	/* Register sysfs hooks */
301 	if ((err = sysfs_create_group(&new_client->dev.kobj, &max1619_group)))
302 		goto exit_free;
303 
304 	data->hwmon_dev = hwmon_device_register(&new_client->dev);
305 	if (IS_ERR(data->hwmon_dev)) {
306 		err = PTR_ERR(data->hwmon_dev);
307 		goto exit_remove_files;
308 	}
309 
310 	return 0;
311 
312 exit_remove_files:
313 	sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
314 exit_free:
315 	kfree(data);
316 exit:
317 	return err;
318 }
319 
320 static void max1619_init_client(struct i2c_client *client)
321 {
322 	u8 config;
323 
324 	/*
325 	 * Start the conversions.
326 	 */
327 	i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
328 				  5); /* 2 Hz */
329 	config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
330 	if (config & 0x40)
331 		i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
332 					  config & 0xBF); /* run */
333 }
334 
335 static int max1619_remove(struct i2c_client *client)
336 {
337 	struct max1619_data *data = i2c_get_clientdata(client);
338 
339 	hwmon_device_unregister(data->hwmon_dev);
340 	sysfs_remove_group(&client->dev.kobj, &max1619_group);
341 
342 	kfree(data);
343 	return 0;
344 }
345 
346 static struct max1619_data *max1619_update_device(struct device *dev)
347 {
348 	struct i2c_client *client = to_i2c_client(dev);
349 	struct max1619_data *data = i2c_get_clientdata(client);
350 
351 	mutex_lock(&data->update_lock);
352 
353 	if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
354 		dev_dbg(&client->dev, "Updating max1619 data.\n");
355 		data->temp_input1 = i2c_smbus_read_byte_data(client,
356 					MAX1619_REG_R_LOCAL_TEMP);
357 		data->temp_input2 = i2c_smbus_read_byte_data(client,
358 					MAX1619_REG_R_REMOTE_TEMP);
359 		data->temp_high2 = i2c_smbus_read_byte_data(client,
360 					MAX1619_REG_R_REMOTE_HIGH);
361 		data->temp_low2 = i2c_smbus_read_byte_data(client,
362 					MAX1619_REG_R_REMOTE_LOW);
363 		data->temp_crit2 = i2c_smbus_read_byte_data(client,
364 					MAX1619_REG_R_REMOTE_CRIT);
365 		data->temp_hyst2 = i2c_smbus_read_byte_data(client,
366 					MAX1619_REG_R_TCRIT_HYST);
367 		data->alarms = i2c_smbus_read_byte_data(client,
368 					MAX1619_REG_R_STATUS);
369 
370 		data->last_updated = jiffies;
371 		data->valid = 1;
372 	}
373 
374 	mutex_unlock(&data->update_lock);
375 
376 	return data;
377 }
378 
379 static int __init sensors_max1619_init(void)
380 {
381 	return i2c_add_driver(&max1619_driver);
382 }
383 
384 static void __exit sensors_max1619_exit(void)
385 {
386 	i2c_del_driver(&max1619_driver);
387 }
388 
389 MODULE_AUTHOR("Alexey Fisher <fishor@mail.ru> and "
390 	"Jean Delvare <khali@linux-fr.org>");
391 MODULE_DESCRIPTION("MAX1619 sensor driver");
392 MODULE_LICENSE("GPL");
393 
394 module_init(sensors_max1619_init);
395 module_exit(sensors_max1619_exit);
396