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1da177e4
LT
1/*
2 ds1621.c - Part of lm_sensors, Linux kernel modules for hardware
3 monitoring
4 Christian W. Zuckschwerdt <zany@triq.net> 2000-11-23
5 based on lm75.c by Frodo Looijaard <frodol@dds.nl>
6 Ported to Linux 2.6 by Aurelien Jarno <aurelien@aurel32.net> with
7 the help of Jean Delvare <khali@linux-fr.org>
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22*/
23
24#include <linux/module.h>
25#include <linux/init.h>
26#include <linux/slab.h>
27#include <linux/jiffies.h>
28#include <linux/i2c.h>
943b0830 29#include <linux/hwmon.h>
46a2e71c 30#include <linux/hwmon-sysfs.h>
943b0830 31#include <linux/err.h>
9a61bf63 32#include <linux/mutex.h>
a5ebe668 33#include <linux/sysfs.h>
1da177e4
LT
34#include "lm75.h"
35
36/* Addresses to scan */
25e9c86d 37static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
1da177e4 38 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
1da177e4
LT
39
40/* Insmod parameters */
f4b50261 41I2C_CLIENT_INSMOD_1(ds1621);
1da177e4
LT
42static int polarity = -1;
43module_param(polarity, int, 0);
44MODULE_PARM_DESC(polarity, "Output's polarity: 0 = active high, 1 = active low");
45
46/* Many DS1621 constants specified below */
47/* Config register used for detection */
48/* 7 6 5 4 3 2 1 0 */
49/* |Done|THF |TLF |NVB | X | X |POL |1SHOT| */
50#define DS1621_REG_CONFIG_NVB 0x10
51#define DS1621_REG_CONFIG_POLARITY 0x02
52#define DS1621_REG_CONFIG_1SHOT 0x01
53#define DS1621_REG_CONFIG_DONE 0x80
54
55/* The DS1621 registers */
46a2e71c
JD
56static const u8 DS1621_REG_TEMP[3] = {
57 0xAA, /* input, word, RO */
58 0xA2, /* min, word, RW */
59 0xA1, /* max, word, RW */
60};
1da177e4
LT
61#define DS1621_REG_CONF 0xAC /* byte, RW */
62#define DS1621_COM_START 0xEE /* no data */
63#define DS1621_COM_STOP 0x22 /* no data */
64
65/* The DS1621 configuration register */
66#define DS1621_ALARM_TEMP_HIGH 0x40
67#define DS1621_ALARM_TEMP_LOW 0x20
68
75819f01 69/* Conversions */
1da177e4
LT
70#define ALARMS_FROM_REG(val) ((val) & \
71 (DS1621_ALARM_TEMP_HIGH | DS1621_ALARM_TEMP_LOW))
72
73/* Each client has this additional data */
74struct ds1621_data {
1beeffe4 75 struct device *hwmon_dev;
9a61bf63 76 struct mutex update_lock;
1da177e4
LT
77 char valid; /* !=0 if following fields are valid */
78 unsigned long last_updated; /* In jiffies */
79
46a2e71c 80 u16 temp[3]; /* Register values, word */
1da177e4
LT
81 u8 conf; /* Register encoding, combined */
82};
83
1da177e4
LT
84/* All registers are word-sized, except for the configuration register.
85 DS1621 uses a high-byte first convention, which is exactly opposite to
75819f01 86 the SMBus standard. */
1da177e4
LT
87static int ds1621_read_value(struct i2c_client *client, u8 reg)
88{
89 if (reg == DS1621_REG_CONF)
90 return i2c_smbus_read_byte_data(client, reg);
91 else
92 return swab16(i2c_smbus_read_word_data(client, reg));
93}
94
1da177e4
LT
95static int ds1621_write_value(struct i2c_client *client, u8 reg, u16 value)
96{
97 if (reg == DS1621_REG_CONF)
98 return i2c_smbus_write_byte_data(client, reg, value);
99 else
100 return i2c_smbus_write_word_data(client, reg, swab16(value));
101}
102
103static void ds1621_init_client(struct i2c_client *client)
104{
105 int reg = ds1621_read_value(client, DS1621_REG_CONF);
44bbe87e 106 /* switch to continuous conversion mode */
1da177e4
LT
107 reg &= ~ DS1621_REG_CONFIG_1SHOT;
108
109 /* setup output polarity */
110 if (polarity == 0)
111 reg &= ~DS1621_REG_CONFIG_POLARITY;
112 else if (polarity == 1)
113 reg |= DS1621_REG_CONFIG_POLARITY;
114
115 ds1621_write_value(client, DS1621_REG_CONF, reg);
116
117 /* start conversion */
118 i2c_smbus_write_byte(client, DS1621_COM_START);
119}
120
9202add6
JD
121static struct ds1621_data *ds1621_update_client(struct device *dev)
122{
123 struct i2c_client *client = to_i2c_client(dev);
124 struct ds1621_data *data = i2c_get_clientdata(client);
125 u8 new_conf;
126
127 mutex_lock(&data->update_lock);
128
129 if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
130 || !data->valid) {
131 int i;
132
133 dev_dbg(&client->dev, "Starting ds1621 update\n");
134
135 data->conf = ds1621_read_value(client, DS1621_REG_CONF);
136
137 for (i = 0; i < ARRAY_SIZE(data->temp); i++)
138 data->temp[i] = ds1621_read_value(client,
139 DS1621_REG_TEMP[i]);
140
141 /* reset alarms if necessary */
142 new_conf = data->conf;
143 if (data->temp[0] > data->temp[1]) /* input > min */
144 new_conf &= ~DS1621_ALARM_TEMP_LOW;
145 if (data->temp[0] < data->temp[2]) /* input < max */
146 new_conf &= ~DS1621_ALARM_TEMP_HIGH;
147 if (data->conf != new_conf)
148 ds1621_write_value(client, DS1621_REG_CONF,
149 new_conf);
150
151 data->last_updated = jiffies;
152 data->valid = 1;
153 }
154
155 mutex_unlock(&data->update_lock);
156
157 return data;
158}
159
46a2e71c
JD
160static ssize_t show_temp(struct device *dev, struct device_attribute *da,
161 char *buf)
162{
163 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
164 struct ds1621_data *data = ds1621_update_client(dev);
165 return sprintf(buf, "%d\n",
166 LM75_TEMP_FROM_REG(data->temp[attr->index]));
1da177e4
LT
167}
168
46a2e71c
JD
169static ssize_t set_temp(struct device *dev, struct device_attribute *da,
170 const char *buf, size_t count)
171{
172 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
173 struct i2c_client *client = to_i2c_client(dev);
174 struct ds1621_data *data = ds1621_update_client(dev);
5bfedac0 175 u16 val = LM75_TEMP_TO_REG(simple_strtol(buf, NULL, 10));
1da177e4 176
46a2e71c
JD
177 mutex_lock(&data->update_lock);
178 data->temp[attr->index] = val;
179 ds1621_write_value(client, DS1621_REG_TEMP[attr->index],
180 data->temp[attr->index]);
181 mutex_unlock(&data->update_lock);
182 return count;
183}
1da177e4 184
46a2e71c
JD
185static ssize_t show_alarms(struct device *dev, struct device_attribute *da,
186 char *buf)
1da177e4
LT
187{
188 struct ds1621_data *data = ds1621_update_client(dev);
189 return sprintf(buf, "%d\n", ALARMS_FROM_REG(data->conf));
190}
191
87f0f31b
JD
192static ssize_t show_alarm(struct device *dev, struct device_attribute *da,
193 char *buf)
194{
195 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
196 struct ds1621_data *data = ds1621_update_client(dev);
197 return sprintf(buf, "%d\n", !!(data->conf & attr->index));
198}
199
1da177e4 200static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
46a2e71c
JD
201static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
202static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_temp, set_temp, 1);
203static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp, set_temp, 2);
87f0f31b
JD
204static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
205 DS1621_ALARM_TEMP_LOW);
206static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
207 DS1621_ALARM_TEMP_HIGH);
1da177e4 208
a5ebe668 209static struct attribute *ds1621_attributes[] = {
46a2e71c
JD
210 &sensor_dev_attr_temp1_input.dev_attr.attr,
211 &sensor_dev_attr_temp1_min.dev_attr.attr,
212 &sensor_dev_attr_temp1_max.dev_attr.attr,
87f0f31b
JD
213 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
214 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
a5ebe668
JD
215 &dev_attr_alarms.attr,
216 NULL
217};
218
219static const struct attribute_group ds1621_group = {
220 .attrs = ds1621_attributes,
221};
222
1da177e4 223
70313eab
JD
224/* Return 0 if detection is successful, -ENODEV otherwise */
225static int ds1621_detect(struct i2c_client *client, int kind,
226 struct i2c_board_info *info)
1da177e4 227{
70313eab 228 struct i2c_adapter *adapter = client->adapter;
1da177e4 229 int conf, temp;
70313eab 230 int i;
1da177e4
LT
231
232 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
233 | I2C_FUNC_SMBUS_WORD_DATA
234 | I2C_FUNC_SMBUS_WRITE_BYTE))
70313eab 235 return -ENODEV;
1da177e4
LT
236
237 /* Now, we do the remaining detection. It is lousy. */
238 if (kind < 0) {
239 /* The NVB bit should be low if no EEPROM write has been
240 requested during the latest 10ms, which is highly
241 improbable in our case. */
75819f01 242 conf = ds1621_read_value(client, DS1621_REG_CONF);
1da177e4 243 if (conf & DS1621_REG_CONFIG_NVB)
70313eab 244 return -ENODEV;
1da177e4 245 /* The 7 lowest bits of a temperature should always be 0. */
70313eab 246 for (i = 0; i < ARRAY_SIZE(DS1621_REG_TEMP); i++) {
46a2e71c
JD
247 temp = ds1621_read_value(client, DS1621_REG_TEMP[i]);
248 if (temp & 0x007f)
70313eab 249 return -ENODEV;
46a2e71c 250 }
1da177e4
LT
251 }
252
70313eab 253 strlcpy(info->type, "ds1621", I2C_NAME_SIZE);
1da177e4 254
70313eab
JD
255 return 0;
256}
257
258static int ds1621_probe(struct i2c_client *client,
259 const struct i2c_device_id *id)
260{
261 struct ds1621_data *data;
262 int err;
263
264 data = kzalloc(sizeof(struct ds1621_data), GFP_KERNEL);
265 if (!data) {
266 err = -ENOMEM;
267 goto exit;
268 }
269
270 i2c_set_clientdata(client, data);
271 mutex_init(&data->update_lock);
1da177e4
LT
272
273 /* Initialize the DS1621 chip */
75819f01 274 ds1621_init_client(client);
1da177e4
LT
275
276 /* Register sysfs hooks */
75819f01 277 if ((err = sysfs_create_group(&client->dev.kobj, &ds1621_group)))
70313eab 278 goto exit_free;
a5ebe668 279
1beeffe4
TJ
280 data->hwmon_dev = hwmon_device_register(&client->dev);
281 if (IS_ERR(data->hwmon_dev)) {
282 err = PTR_ERR(data->hwmon_dev);
a5ebe668 283 goto exit_remove_files;
943b0830
MH
284 }
285
1da177e4
LT
286 return 0;
287
a5ebe668 288 exit_remove_files:
75819f01 289 sysfs_remove_group(&client->dev.kobj, &ds1621_group);
1da177e4
LT
290 exit_free:
291 kfree(data);
292 exit:
293 return err;
294}
295
70313eab 296static int ds1621_remove(struct i2c_client *client)
1da177e4 297{
943b0830 298 struct ds1621_data *data = i2c_get_clientdata(client);
1da177e4 299
1beeffe4 300 hwmon_device_unregister(data->hwmon_dev);
a5ebe668 301 sysfs_remove_group(&client->dev.kobj, &ds1621_group);
943b0830 302
943b0830 303 kfree(data);
1da177e4
LT
304
305 return 0;
306}
307
9202add6
JD
308static const struct i2c_device_id ds1621_id[] = {
309 { "ds1621", ds1621 },
310 { "ds1625", ds1621 },
311 { }
312};
313MODULE_DEVICE_TABLE(i2c, ds1621_id);
1da177e4 314
9202add6
JD
315/* This is the driver that will be inserted */
316static struct i2c_driver ds1621_driver = {
317 .class = I2C_CLASS_HWMON,
318 .driver = {
319 .name = "ds1621",
320 },
321 .probe = ds1621_probe,
322 .remove = ds1621_remove,
323 .id_table = ds1621_id,
324 .detect = ds1621_detect,
325 .address_data = &addr_data,
326};
1da177e4
LT
327
328static int __init ds1621_init(void)
329{
330 return i2c_add_driver(&ds1621_driver);
331}
332
333static void __exit ds1621_exit(void)
334{
335 i2c_del_driver(&ds1621_driver);
336}
337
338
339MODULE_AUTHOR("Christian W. Zuckschwerdt <zany@triq.net>");
340MODULE_DESCRIPTION("DS1621 driver");
341MODULE_LICENSE("GPL");
342
343module_init(ds1621_init);
344module_exit(ds1621_exit);