1 /*
2 * Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor)
3 *
4 * Copyright (C) 2008, 2010 Pengutronix
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * TODO: SPI, support for external temperature sensor
11 * use power-down mode for suspend?, interrupt handling?
12 */
13
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/err.h>
18 #include <linux/mutex.h>
19 #include <linux/jiffies.h>
20 #include <linux/i2c.h>
21 #include <linux/hwmon.h>
22 #include <linux/hwmon-sysfs.h>
23 #include <linux/slab.h>
24
25 #define ADT7411_REG_INT_TEMP_VDD_LSB 0x03
26 #define ADT7411_REG_EXT_TEMP_AIN14_LSB 0x04
27 #define ADT7411_REG_VDD_MSB 0x06
28 #define ADT7411_REG_INT_TEMP_MSB 0x07
29 #define ADT7411_REG_EXT_TEMP_AIN1_MSB 0x08
30
31 #define ADT7411_REG_CFG1 0x18
32 #define ADT7411_CFG1_START_MONITOR (1 << 0)
33
34 #define ADT7411_REG_CFG2 0x19
35 #define ADT7411_CFG2_DISABLE_AVG (1 << 5)
36
37 #define ADT7411_REG_CFG3 0x1a
38 #define ADT7411_CFG3_ADC_CLK_225 (1 << 0)
39 #define ADT7411_CFG3_REF_VDD (1 << 4)
40
41 #define ADT7411_REG_DEVICE_ID 0x4d
42 #define ADT7411_REG_MANUFACTURER_ID 0x4e
43
44 #define ADT7411_DEVICE_ID 0x2
45 #define ADT7411_MANUFACTURER_ID 0x41
46
47 static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };
48
49 struct adt7411_data {
50 struct mutex device_lock; /* for "atomic" device accesses */
51 struct mutex update_lock;
52 unsigned long next_update;
53 int vref_cached;
54 struct i2c_client *client;
55 };
56
57 /*
58 * When reading a register containing (up to 4) lsb, all associated
59 * msb-registers get locked by the hardware. After _one_ of those msb is read,
60 * _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
61 * is protected here with a mutex, too.
62 */
adt7411_read_10_bit(struct i2c_client * client,u8 lsb_reg,u8 msb_reg,u8 lsb_shift)63 static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
64 u8 msb_reg, u8 lsb_shift)
65 {
66 struct adt7411_data *data = i2c_get_clientdata(client);
67 int val, tmp;
68
69 mutex_lock(&data->device_lock);
70
71 val = i2c_smbus_read_byte_data(client, lsb_reg);
72 if (val < 0)
73 goto exit_unlock;
74
75 tmp = (val >> lsb_shift) & 3;
76 val = i2c_smbus_read_byte_data(client, msb_reg);
77
78 if (val >= 0)
79 val = (val << 2) | tmp;
80
81 exit_unlock:
82 mutex_unlock(&data->device_lock);
83
84 return val;
85 }
86
adt7411_modify_bit(struct i2c_client * client,u8 reg,u8 bit,bool flag)87 static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
88 bool flag)
89 {
90 struct adt7411_data *data = i2c_get_clientdata(client);
91 int ret, val;
92
93 mutex_lock(&data->device_lock);
94
95 ret = i2c_smbus_read_byte_data(client, reg);
96 if (ret < 0)
97 goto exit_unlock;
98
99 if (flag)
100 val = ret | bit;
101 else
102 val = ret & ~bit;
103
104 ret = i2c_smbus_write_byte_data(client, reg, val);
105
106 exit_unlock:
107 mutex_unlock(&data->device_lock);
108 return ret;
109 }
110
adt7411_show_vdd(struct device * dev,struct device_attribute * attr,char * buf)111 static ssize_t adt7411_show_vdd(struct device *dev,
112 struct device_attribute *attr, char *buf)
113 {
114 struct adt7411_data *data = dev_get_drvdata(dev);
115 struct i2c_client *client = data->client;
116 int ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
117 ADT7411_REG_VDD_MSB, 2);
118
119 return ret < 0 ? ret : sprintf(buf, "%u\n", ret * 7000 / 1024);
120 }
121
adt7411_show_temp(struct device * dev,struct device_attribute * attr,char * buf)122 static ssize_t adt7411_show_temp(struct device *dev,
123 struct device_attribute *attr, char *buf)
124 {
125 struct adt7411_data *data = dev_get_drvdata(dev);
126 struct i2c_client *client = data->client;
127 int val = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
128 ADT7411_REG_INT_TEMP_MSB, 0);
129
130 if (val < 0)
131 return val;
132
133 val = val & 0x200 ? val - 0x400 : val; /* 10 bit signed */
134
135 return sprintf(buf, "%d\n", val * 250);
136 }
137
adt7411_show_input(struct device * dev,struct device_attribute * attr,char * buf)138 static ssize_t adt7411_show_input(struct device *dev,
139 struct device_attribute *attr, char *buf)
140 {
141 int nr = to_sensor_dev_attr(attr)->index;
142 struct adt7411_data *data = dev_get_drvdata(dev);
143 struct i2c_client *client = data->client;
144 int val;
145 u8 lsb_reg, lsb_shift;
146
147 mutex_lock(&data->update_lock);
148 if (time_after_eq(jiffies, data->next_update)) {
149 val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
150 if (val < 0)
151 goto exit_unlock;
152
153 if (val & ADT7411_CFG3_REF_VDD) {
154 val = adt7411_read_10_bit(client,
155 ADT7411_REG_INT_TEMP_VDD_LSB,
156 ADT7411_REG_VDD_MSB, 2);
157 if (val < 0)
158 goto exit_unlock;
159
160 data->vref_cached = val * 7000 / 1024;
161 } else {
162 data->vref_cached = 2250;
163 }
164
165 data->next_update = jiffies + HZ;
166 }
167
168 lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
169 lsb_shift = 2 * (nr & 0x03);
170 val = adt7411_read_10_bit(client, lsb_reg,
171 ADT7411_REG_EXT_TEMP_AIN1_MSB + nr, lsb_shift);
172 if (val < 0)
173 goto exit_unlock;
174
175 val = sprintf(buf, "%u\n", val * data->vref_cached / 1024);
176 exit_unlock:
177 mutex_unlock(&data->update_lock);
178 return val;
179 }
180
adt7411_show_bit(struct device * dev,struct device_attribute * attr,char * buf)181 static ssize_t adt7411_show_bit(struct device *dev,
182 struct device_attribute *attr, char *buf)
183 {
184 struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
185 struct adt7411_data *data = dev_get_drvdata(dev);
186 struct i2c_client *client = data->client;
187 int ret = i2c_smbus_read_byte_data(client, attr2->index);
188
189 return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
190 }
191
adt7411_set_bit(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)192 static ssize_t adt7411_set_bit(struct device *dev,
193 struct device_attribute *attr, const char *buf,
194 size_t count)
195 {
196 struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
197 struct adt7411_data *data = dev_get_drvdata(dev);
198 struct i2c_client *client = data->client;
199 int ret;
200 unsigned long flag;
201
202 ret = kstrtoul(buf, 0, &flag);
203 if (ret || flag > 1)
204 return -EINVAL;
205
206 ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);
207
208 /* force update */
209 mutex_lock(&data->update_lock);
210 data->next_update = jiffies;
211 mutex_unlock(&data->update_lock);
212
213 return ret < 0 ? ret : count;
214 }
215
216 #define ADT7411_BIT_ATTR(__name, __reg, __bit) \
217 SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \
218 adt7411_set_bit, __bit, __reg)
219
220 static DEVICE_ATTR(temp1_input, S_IRUGO, adt7411_show_temp, NULL);
221 static DEVICE_ATTR(in0_input, S_IRUGO, adt7411_show_vdd, NULL);
222 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, adt7411_show_input, NULL, 0);
223 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, adt7411_show_input, NULL, 1);
224 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, adt7411_show_input, NULL, 2);
225 static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, adt7411_show_input, NULL, 3);
226 static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, adt7411_show_input, NULL, 4);
227 static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, adt7411_show_input, NULL, 5);
228 static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, adt7411_show_input, NULL, 6);
229 static SENSOR_DEVICE_ATTR(in8_input, S_IRUGO, adt7411_show_input, NULL, 7);
230 static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
231 static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
232 static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);
233
234 static struct attribute *adt7411_attrs[] = {
235 &dev_attr_temp1_input.attr,
236 &dev_attr_in0_input.attr,
237 &sensor_dev_attr_in1_input.dev_attr.attr,
238 &sensor_dev_attr_in2_input.dev_attr.attr,
239 &sensor_dev_attr_in3_input.dev_attr.attr,
240 &sensor_dev_attr_in4_input.dev_attr.attr,
241 &sensor_dev_attr_in5_input.dev_attr.attr,
242 &sensor_dev_attr_in6_input.dev_attr.attr,
243 &sensor_dev_attr_in7_input.dev_attr.attr,
244 &sensor_dev_attr_in8_input.dev_attr.attr,
245 &sensor_dev_attr_no_average.dev_attr.attr,
246 &sensor_dev_attr_fast_sampling.dev_attr.attr,
247 &sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
248 NULL
249 };
250
251 ATTRIBUTE_GROUPS(adt7411);
252
adt7411_detect(struct i2c_client * client,struct i2c_board_info * info)253 static int adt7411_detect(struct i2c_client *client,
254 struct i2c_board_info *info)
255 {
256 int val;
257
258 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
259 return -ENODEV;
260
261 val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID);
262 if (val < 0 || val != ADT7411_MANUFACTURER_ID) {
263 dev_dbg(&client->dev,
264 "Wrong manufacturer ID. Got %d, expected %d\n",
265 val, ADT7411_MANUFACTURER_ID);
266 return -ENODEV;
267 }
268
269 val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
270 if (val < 0 || val != ADT7411_DEVICE_ID) {
271 dev_dbg(&client->dev,
272 "Wrong device ID. Got %d, expected %d\n",
273 val, ADT7411_DEVICE_ID);
274 return -ENODEV;
275 }
276
277 strlcpy(info->type, "adt7411", I2C_NAME_SIZE);
278
279 return 0;
280 }
281
adt7411_probe(struct i2c_client * client,const struct i2c_device_id * id)282 static int adt7411_probe(struct i2c_client *client,
283 const struct i2c_device_id *id)
284 {
285 struct device *dev = &client->dev;
286 struct adt7411_data *data;
287 struct device *hwmon_dev;
288 int ret;
289
290 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
291 if (!data)
292 return -ENOMEM;
293
294 i2c_set_clientdata(client, data);
295 data->client = client;
296 mutex_init(&data->device_lock);
297 mutex_init(&data->update_lock);
298
299 ret = adt7411_modify_bit(client, ADT7411_REG_CFG1,
300 ADT7411_CFG1_START_MONITOR, 1);
301 if (ret < 0)
302 return ret;
303
304 /* force update on first occasion */
305 data->next_update = jiffies;
306
307 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
308 data,
309 adt7411_groups);
310 return PTR_ERR_OR_ZERO(hwmon_dev);
311 }
312
313 static const struct i2c_device_id adt7411_id[] = {
314 { "adt7411", 0 },
315 { }
316 };
317 MODULE_DEVICE_TABLE(i2c, adt7411_id);
318
319 static struct i2c_driver adt7411_driver = {
320 .driver = {
321 .name = "adt7411",
322 },
323 .probe = adt7411_probe,
324 .id_table = adt7411_id,
325 .detect = adt7411_detect,
326 .address_list = normal_i2c,
327 .class = I2C_CLASS_HWMON,
328 };
329
330 module_i2c_driver(adt7411_driver);
331
332 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
333 "Wolfram Sang <w.sang@pengutronix.de>");
334 MODULE_DESCRIPTION("ADT7411 driver");
335 MODULE_LICENSE("GPL v2");
336