1 /*
2 * max1619.c - Part of lm_sensors, Linux kernel modules for hardware
3 * monitoring
4 * Copyright (C) 2003-2004 Oleksij Rempel <bug-track@fisher-privat.net>
5 * Jean Delvare <jdelvare@suse.de>
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
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>
29 #include <linux/hwmon.h>
30 #include <linux/hwmon-sysfs.h>
31 #include <linux/err.h>
32 #include <linux/mutex.h>
33 #include <linux/sysfs.h>
34
35 static const unsigned short normal_i2c[] = {
36 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
37
38 /*
39 * The MAX1619 registers
40 */
41
42 #define MAX1619_REG_R_MAN_ID 0xFE
43 #define MAX1619_REG_R_CHIP_ID 0xFF
44 #define MAX1619_REG_R_CONFIG 0x03
45 #define MAX1619_REG_W_CONFIG 0x09
46 #define MAX1619_REG_R_CONVRATE 0x04
47 #define MAX1619_REG_W_CONVRATE 0x0A
48 #define MAX1619_REG_R_STATUS 0x02
49 #define MAX1619_REG_R_LOCAL_TEMP 0x00
50 #define MAX1619_REG_R_REMOTE_TEMP 0x01
51 #define MAX1619_REG_R_REMOTE_HIGH 0x07
52 #define MAX1619_REG_W_REMOTE_HIGH 0x0D
53 #define MAX1619_REG_R_REMOTE_LOW 0x08
54 #define MAX1619_REG_W_REMOTE_LOW 0x0E
55 #define MAX1619_REG_R_REMOTE_CRIT 0x10
56 #define MAX1619_REG_W_REMOTE_CRIT 0x12
57 #define MAX1619_REG_R_TCRIT_HYST 0x11
58 #define MAX1619_REG_W_TCRIT_HYST 0x13
59
60 /*
61 * Conversions
62 */
63
temp_from_reg(int val)64 static int temp_from_reg(int val)
65 {
66 return (val & 0x80 ? val-0x100 : val) * 1000;
67 }
68
temp_to_reg(int val)69 static int temp_to_reg(int val)
70 {
71 return (val < 0 ? val+0x100*1000 : val) / 1000;
72 }
73
74 enum temp_index {
75 t_input1 = 0,
76 t_input2,
77 t_low2,
78 t_high2,
79 t_crit2,
80 t_hyst2,
81 t_num_regs
82 };
83
84 /*
85 * Client data (each client gets its own)
86 */
87
88 struct max1619_data {
89 struct i2c_client *client;
90 struct mutex update_lock;
91 char valid; /* zero until following fields are valid */
92 unsigned long last_updated; /* in jiffies */
93
94 /* registers values */
95 u8 temp[t_num_regs]; /* index with enum temp_index */
96 u8 alarms;
97 };
98
99 static const u8 regs_read[t_num_regs] = {
100 [t_input1] = MAX1619_REG_R_LOCAL_TEMP,
101 [t_input2] = MAX1619_REG_R_REMOTE_TEMP,
102 [t_low2] = MAX1619_REG_R_REMOTE_LOW,
103 [t_high2] = MAX1619_REG_R_REMOTE_HIGH,
104 [t_crit2] = MAX1619_REG_R_REMOTE_CRIT,
105 [t_hyst2] = MAX1619_REG_R_TCRIT_HYST,
106 };
107
108 static const u8 regs_write[t_num_regs] = {
109 [t_low2] = MAX1619_REG_W_REMOTE_LOW,
110 [t_high2] = MAX1619_REG_W_REMOTE_HIGH,
111 [t_crit2] = MAX1619_REG_W_REMOTE_CRIT,
112 [t_hyst2] = MAX1619_REG_W_TCRIT_HYST,
113 };
114
max1619_update_device(struct device * dev)115 static struct max1619_data *max1619_update_device(struct device *dev)
116 {
117 struct max1619_data *data = dev_get_drvdata(dev);
118 struct i2c_client *client = data->client;
119 int config, i;
120
121 mutex_lock(&data->update_lock);
122
123 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
124 dev_dbg(&client->dev, "Updating max1619 data.\n");
125 for (i = 0; i < t_num_regs; i++)
126 data->temp[i] = i2c_smbus_read_byte_data(client,
127 regs_read[i]);
128 data->alarms = i2c_smbus_read_byte_data(client,
129 MAX1619_REG_R_STATUS);
130 /* If OVERT polarity is low, reverse alarm bit */
131 config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
132 if (!(config & 0x20))
133 data->alarms ^= 0x02;
134
135 data->last_updated = jiffies;
136 data->valid = 1;
137 }
138
139 mutex_unlock(&data->update_lock);
140
141 return data;
142 }
143
144 /*
145 * Sysfs stuff
146 */
147
show_temp(struct device * dev,struct device_attribute * devattr,char * buf)148 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
149 char *buf)
150 {
151 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
152 struct max1619_data *data = max1619_update_device(dev);
153
154 return sprintf(buf, "%d\n", temp_from_reg(data->temp[attr->index]));
155 }
156
set_temp(struct device * dev,struct device_attribute * devattr,const char * buf,size_t count)157 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
158 const char *buf, size_t count)
159 {
160 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
161 struct max1619_data *data = dev_get_drvdata(dev);
162 struct i2c_client *client = data->client;
163 long val;
164 int err = kstrtol(buf, 10, &val);
165 if (err)
166 return err;
167
168 mutex_lock(&data->update_lock);
169 data->temp[attr->index] = temp_to_reg(val);
170 i2c_smbus_write_byte_data(client, regs_write[attr->index],
171 data->temp[attr->index]);
172 mutex_unlock(&data->update_lock);
173 return count;
174 }
175
show_alarms(struct device * dev,struct device_attribute * attr,char * buf)176 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr,
177 char *buf)
178 {
179 struct max1619_data *data = max1619_update_device(dev);
180 return sprintf(buf, "%d\n", data->alarms);
181 }
182
show_alarm(struct device * dev,struct device_attribute * attr,char * buf)183 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
184 char *buf)
185 {
186 int bitnr = to_sensor_dev_attr(attr)->index;
187 struct max1619_data *data = max1619_update_device(dev);
188 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
189 }
190
191 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, t_input1);
192 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, t_input2);
193 static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp, set_temp,
194 t_low2);
195 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp, set_temp,
196 t_high2);
197 static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp, set_temp,
198 t_crit2);
199 static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp,
200 set_temp, t_hyst2);
201
202 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
203 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
204 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
205 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
206 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
207
208 static struct attribute *max1619_attrs[] = {
209 &sensor_dev_attr_temp1_input.dev_attr.attr,
210 &sensor_dev_attr_temp2_input.dev_attr.attr,
211 &sensor_dev_attr_temp2_min.dev_attr.attr,
212 &sensor_dev_attr_temp2_max.dev_attr.attr,
213 &sensor_dev_attr_temp2_crit.dev_attr.attr,
214 &sensor_dev_attr_temp2_crit_hyst.dev_attr.attr,
215
216 &dev_attr_alarms.attr,
217 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
218 &sensor_dev_attr_temp2_fault.dev_attr.attr,
219 &sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
220 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
221 NULL
222 };
223 ATTRIBUTE_GROUPS(max1619);
224
225 /* Return 0 if detection is successful, -ENODEV otherwise */
max1619_detect(struct i2c_client * client,struct i2c_board_info * info)226 static int max1619_detect(struct i2c_client *client,
227 struct i2c_board_info *info)
228 {
229 struct i2c_adapter *adapter = client->adapter;
230 u8 reg_config, reg_convrate, reg_status, man_id, chip_id;
231
232 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
233 return -ENODEV;
234
235 /* detection */
236 reg_config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
237 reg_convrate = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONVRATE);
238 reg_status = i2c_smbus_read_byte_data(client, MAX1619_REG_R_STATUS);
239 if ((reg_config & 0x03) != 0x00
240 || reg_convrate > 0x07 || (reg_status & 0x61) != 0x00) {
241 dev_dbg(&adapter->dev, "MAX1619 detection failed at 0x%02x\n",
242 client->addr);
243 return -ENODEV;
244 }
245
246 /* identification */
247 man_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_MAN_ID);
248 chip_id = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CHIP_ID);
249 if (man_id != 0x4D || chip_id != 0x04) {
250 dev_info(&adapter->dev,
251 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X).\n",
252 man_id, chip_id);
253 return -ENODEV;
254 }
255
256 strlcpy(info->type, "max1619", I2C_NAME_SIZE);
257
258 return 0;
259 }
260
max1619_init_client(struct i2c_client * client)261 static void max1619_init_client(struct i2c_client *client)
262 {
263 u8 config;
264
265 /*
266 * Start the conversions.
267 */
268 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
269 5); /* 2 Hz */
270 config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
271 if (config & 0x40)
272 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
273 config & 0xBF); /* run */
274 }
275
max1619_probe(struct i2c_client * new_client,const struct i2c_device_id * id)276 static int max1619_probe(struct i2c_client *new_client,
277 const struct i2c_device_id *id)
278 {
279 struct max1619_data *data;
280 struct device *hwmon_dev;
281
282 data = devm_kzalloc(&new_client->dev, sizeof(struct max1619_data),
283 GFP_KERNEL);
284 if (!data)
285 return -ENOMEM;
286
287 data->client = new_client;
288 mutex_init(&data->update_lock);
289
290 /* Initialize the MAX1619 chip */
291 max1619_init_client(new_client);
292
293 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev,
294 new_client->name,
295 data,
296 max1619_groups);
297 return PTR_ERR_OR_ZERO(hwmon_dev);
298 }
299
300 static const struct i2c_device_id max1619_id[] = {
301 { "max1619", 0 },
302 { }
303 };
304 MODULE_DEVICE_TABLE(i2c, max1619_id);
305
306 static struct i2c_driver max1619_driver = {
307 .class = I2C_CLASS_HWMON,
308 .driver = {
309 .name = "max1619",
310 },
311 .probe = max1619_probe,
312 .id_table = max1619_id,
313 .detect = max1619_detect,
314 .address_list = normal_i2c,
315 };
316
317 module_i2c_driver(max1619_driver);
318
319 MODULE_AUTHOR("Oleksij Rempel <bug-track@fisher-privat.net>, Jean Delvare <jdelvare@suse.de>");
320 MODULE_DESCRIPTION("MAX1619 sensor driver");
321 MODULE_LICENSE("GPL");
322