summaryrefslogtreecommitdiffstats
path: root/drivers/hwmon/max1619.c
blob: 4c23afe113e2f71b6d9b9356e59122abfc3484c4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
/*
 * max1619.c - Part of lm_sensors, Linux kernel modules for hardware
 *             monitoring
 * Copyright (C) 2003-2004 Oleksij Rempel <bug-track@fisher-privat.net>
 *                         Jean Delvare <jdelvare@suse.de>
 *
 * Based on the lm90 driver. The MAX1619 is a sensor chip made by Maxim.
 * It reports up to two temperatures (its own plus up to
 * one external one). Complete datasheet can be
 * obtained from Maxim's website at:
 *   http://pdfserv.maxim-ic.com/en/ds/MAX1619.pdf
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */


#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/sysfs.h>

static const unsigned short normal_i2c[] = {
	0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };

/*
 * The MAX1619 registers
 */

#define MAX1619_REG_R_MAN_ID		0xFE
#define MAX1619_REG_R_CHIP_ID		0xFF
#define MAX1619_REG_R_CONFIG		0x03
#define MAX1619_REG_W_CONFIG		0x09
#define MAX1619_REG_R_CONVRATE		0x04
#define MAX1619_REG_W_CONVRATE		0x0A
#define MAX1619_REG_R_STATUS		0x02
#define MAX1619_REG_R_LOCAL_TEMP	0x00
#define MAX1619_REG_R_REMOTE_TEMP	0x01
#define MAX1619_REG_R_REMOTE_HIGH	0x07
#define MAX1619_REG_W_REMOTE_HIGH	0x0D
#define MAX1619_REG_R_REMOTE_LOW	0x08
#define MAX1619_REG_W_REMOTE_LOW	0x0E
#define MAX1619_REG_R_REMOTE_CRIT	0x10
#define MAX1619_REG_W_REMOTE_CRIT	0x12
#define MAX1619_REG_R_TCRIT_HYST	0x11
#define MAX1619_REG_W_TCRIT_HYST	0x13

/*
 * Conversions
 */

static int temp_from_reg(int val)
{
	return (val & 0x80 ? val-0x100 : val) * 1000;
}

static int temp_to_reg(int val)
{
	return (val < 0 ? val+0x100*1000 : val) / 1000;
}

/*
 * Functions declaration
 */

static int max1619_probe(struct i2c_client *client,
			 const struct i2c_device_id *id);
static int max1619_detect(struct i2c_client *client,
			  struct i2c_board_info *info);
static void max1619_init_client(struct i2c_client *client);
static int max1619_remove(struct i2c_client *client);
static struct max1619_data *max1619_update_device(struct device *dev);

/*
 * Driver data (common to all clients)
 */

static const struct i2c_device_id max1619_id[] = {
	{ "max1619", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, max1619_id);

static struct i2c_driver max1619_driver = {
	.class		= I2C_CLASS_HWMON,
	.driver = {
		.name	= "max1619",
	},
	.probe		= max1619_probe,
	.remove		= max1619_remove,
	.id_table	= max1619_id,
	.detect		= max1619_detect,
	.address_list	= normal_i2c,
};

/*
 * Client data (each client gets its own)
 */

struct max1619_data {
	struct device *hwmon_dev;
	struct mutex update_lock;
	char valid; /* zero until following fields are valid */
	unsigned long last_updated; /* in jiffies */

	/* registers values */
	u8 temp_input1; /* local */
	u8 temp_input2, temp_low2, temp_high2; /* remote */
	u8 temp_crit2;
	u8 temp_hyst2;
	u8 alarms;
};

/*
 * Sysfs stuff
 */

#define show_temp(value) \
static ssize_t show_##value(struct device *dev, struct device_attribute *attr, \
			    char *buf) \
{ \
	struct max1619_data *data = max1619_update_device(dev); \
	return sprintf(buf, "%d\n", temp_from_reg(data->value)); \
}
show_temp(temp_input1);
show_temp(temp_input2);
show_temp(temp_low2);
show_temp(temp_high2);
show_temp(temp_crit2);
show_temp(temp_hyst2);

#define set_temp2(value, reg) \
static ssize_t set_##value(struct device *dev, struct device_attribute *attr, \
			   const char *buf, \
	size_t count) \
{ \
	struct i2c_client *client = to_i2c_client(dev); \
	struct max1619_data *data = i2c_get_clientdata(client); \
	long val; \
	int err = kstrtol(buf, 10, &val); \
	if (err) \
		return err; \
\
	mutex_lock(&data->update_lock); \
	data->value = temp_to_reg(val); \
	i2c_smbus_write_byte_data(client, reg, data->value); \
	mutex_unlock(&data->update_lock); \
	return count; \
}

set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);

static ssize_t show_alarms(struct device *dev, struct device_attribute *attr,
			   char *buf)
{
	struct max1619_data *data = max1619_update_device(dev);
	return sprintf(buf, "%d\n", data->alarms);
}

static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
			  char *buf)
{
	int bitnr = to_sensor_dev_attr(attr)->index;
	struct max1619_data *data = max1619_update_device(dev);
	return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
}

static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
	set_temp_low2);
static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
	set_temp_high2);
static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
	set_temp_crit2);
static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
	set_temp_hyst2);
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);

static struct attribute *max1619_attributes[] = {
	&dev_attr_temp1_input.attr,
	&dev_attr_temp2_input.attr,
	&dev_attr_temp2_min.attr,
	&dev_attr_temp2_max.attr,
	&dev_attr_temp2_crit.attr,
	&dev_attr_temp2_crit_hyst.attr,

	&dev_attr_alarms.attr,
	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
	&sensor_dev_attr_temp2_fault.dev_attr.attr,
	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
	NULL
};

static const struct attribute_group max1619_group = {
	.attrs = max1619_attributes,
};

/*
 * Real code
 */

/* Return 0 if detection is successful, -ENODEV otherwise */
static int max1619_detect(struct i2c_client *client,
			  struct i2c_board_info *info)
{
	struct i2c_adapter *adapter = client->adapter;
	u8 reg_config, reg_convrate, reg_status, man_id, chip_id;

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
		return -ENODEV;

	/* detection */
	reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
	reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONVRATE);
	reg_status = i2c_smbus_read_byte_data(client, MAX1619_REG_R_STATUS);
	if ((reg_config & 0x03) != 0x00
	 || reg_convrate > 0x07 || (reg_status & 0x61) != 0x00) {
		dev_dbg(&adapter->dev, "MAX1619 detection failed at 0x%02x\n",
			client->addr);
		return -ENODEV;
	}

	/* identification */
	man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_MAN_ID);
	chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CHIP_ID);
	if (man_id != 0x4D || chip_id != 0x04) {
		dev_info(&adapter->dev,
			 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n",
			 man_id, chip_id);
		return -ENODEV;
	}

	strlcpy(info->type, "max1619", I2C_NAME_SIZE);

	return 0;
}

static int max1619_probe(struct i2c_client *new_client,
			 const struct i2c_device_id *id)
{
	struct max1619_data *data;
	int err;

	data = devm_kzalloc(&new_client->dev, sizeof(struct max1619_data),
			    GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	i2c_set_clientdata(new_client, data);
	mutex_init(&data->update_lock);

	/* Initialize the MAX1619 chip */
	max1619_init_client(new_client);

	/* Register sysfs hooks */
	err = sysfs_create_group(&new_client->dev.kobj, &max1619_group);
	if (err)
		return err;

	data->hwmon_dev = hwmon_device_register(&new_client->dev);
	if (IS_ERR(data->hwmon_dev)) {
		err = PTR_ERR(data->hwmon_dev);
		goto exit_remove_files;
	}

	return 0;

exit_remove_files:
	sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
	return err;
}

static void max1619_init_client(struct i2c_client *client)
{
	u8 config;

	/*
	 * Start the conversions.
	 */
	i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
				  5); /* 2 Hz */
	config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
	if (config & 0x40)
		i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
					  config & 0xBF); /* run */
}

static int max1619_remove(struct i2c_client *client)
{
	struct max1619_data *data = i2c_get_clientdata(client);

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &max1619_group);

	return 0;
}

static struct max1619_data *max1619_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct max1619_data *data = i2c_get_clientdata(client);

	mutex_lock(&data->update_lock);

	if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
		dev_dbg(&client->dev, "Updating max1619 data.\n");
		data->temp_input1 = i2c_smbus_read_byte_data(client,
					MAX1619_REG_R_LOCAL_TEMP);
		data->temp_input2 = i2c_smbus_read_byte_data(client,
					MAX1619_REG_R_REMOTE_TEMP);
		data->temp_high2 = i2c_smbus_read_byte_data(client,
					MAX1619_REG_R_REMOTE_HIGH);
		data->temp_low2 = i2c_smbus_read_byte_data(client,
					MAX1619_REG_R_REMOTE_LOW);
		data->temp_crit2 = i2c_smbus_read_byte_data(client,
					MAX1619_REG_R_REMOTE_CRIT);
		data->temp_hyst2 = i2c_smbus_read_byte_data(client,
					MAX1619_REG_R_TCRIT_HYST);
		data->alarms = i2c_smbus_read_byte_data(client,
					MAX1619_REG_R_STATUS);

		data->last_updated = jiffies;
		data->valid = 1;
	}

	mutex_unlock(&data->update_lock);

	return data;
}

module_i2c_driver(max1619_driver);

MODULE_AUTHOR("Oleksij Rempel <bug-track@fisher-privat.net>, Jean Delvare <jdelvare@suse.de>");
MODULE_DESCRIPTION("MAX1619 sensor driver");
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud