xref: /linux/drivers/hwmon/adt7411.c (revision 4413e16d9d21673bb5048a2e542f1aaa00015c2e)
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/delay.h>
19 #include <linux/mutex.h>
20 #include <linux/jiffies.h>
21 #include <linux/i2c.h>
22 #include <linux/hwmon.h>
23 #include <linux/hwmon-sysfs.h>
24 #include <linux/slab.h>
25 
26 #define ADT7411_REG_INT_TEMP_VDD_LSB		0x03
27 #define ADT7411_REG_EXT_TEMP_AIN14_LSB		0x04
28 #define ADT7411_REG_VDD_MSB			0x06
29 #define ADT7411_REG_INT_TEMP_MSB		0x07
30 #define ADT7411_REG_EXT_TEMP_AIN1_MSB		0x08
31 
32 #define ADT7411_REG_CFG1			0x18
33 #define ADT7411_CFG1_START_MONITOR		(1 << 0)
34 
35 #define ADT7411_REG_CFG2			0x19
36 #define ADT7411_CFG2_DISABLE_AVG		(1 << 5)
37 
38 #define ADT7411_REG_CFG3			0x1a
39 #define ADT7411_CFG3_ADC_CLK_225		(1 << 0)
40 #define ADT7411_CFG3_REF_VDD			(1 << 4)
41 
42 #define ADT7411_REG_DEVICE_ID			0x4d
43 #define ADT7411_REG_MANUFACTURER_ID		0x4e
44 
45 #define ADT7411_DEVICE_ID			0x2
46 #define ADT7411_MANUFACTURER_ID			0x41
47 
48 static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };
49 
50 struct adt7411_data {
51 	struct mutex device_lock;	/* for "atomic" device accesses */
52 	struct mutex update_lock;
53 	unsigned long next_update;
54 	int vref_cached;
55 	struct device *hwmon_dev;
56 };
57 
58 /*
59  * When reading a register containing (up to 4) lsb, all associated
60  * msb-registers get locked by the hardware. After _one_ of those msb is read,
61  * _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
62  * is protected here with a mutex, too.
63  */
64 static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
65 				u8 msb_reg, u8 lsb_shift)
66 {
67 	struct adt7411_data *data = i2c_get_clientdata(client);
68 	int val, tmp;
69 
70 	mutex_lock(&data->device_lock);
71 
72 	val = i2c_smbus_read_byte_data(client, lsb_reg);
73 	if (val < 0)
74 		goto exit_unlock;
75 
76 	tmp = (val >> lsb_shift) & 3;
77 	val = i2c_smbus_read_byte_data(client, msb_reg);
78 
79 	if (val >= 0)
80 		val = (val << 2) | tmp;
81 
82  exit_unlock:
83 	mutex_unlock(&data->device_lock);
84 
85 	return val;
86 }
87 
88 static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
89 				bool flag)
90 {
91 	struct adt7411_data *data = i2c_get_clientdata(client);
92 	int ret, val;
93 
94 	mutex_lock(&data->device_lock);
95 
96 	ret = i2c_smbus_read_byte_data(client, reg);
97 	if (ret < 0)
98 		goto exit_unlock;
99 
100 	if (flag)
101 		val = ret | bit;
102 	else
103 		val = ret & ~bit;
104 
105 	ret = i2c_smbus_write_byte_data(client, reg, val);
106 
107  exit_unlock:
108 	mutex_unlock(&data->device_lock);
109 	return ret;
110 }
111 
112 static ssize_t adt7411_show_vdd(struct device *dev,
113 				struct device_attribute *attr, char *buf)
114 {
115 	struct i2c_client *client = to_i2c_client(dev);
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 
122 static ssize_t adt7411_show_temp(struct device *dev,
123 			struct device_attribute *attr, char *buf)
124 {
125 	struct i2c_client *client = to_i2c_client(dev);
126 	int val = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
127 			ADT7411_REG_INT_TEMP_MSB, 0);
128 
129 	if (val < 0)
130 		return val;
131 
132 	val = val & 0x200 ? val - 0x400 : val; /* 10 bit signed */
133 
134 	return sprintf(buf, "%d\n", val * 250);
135 }
136 
137 static ssize_t adt7411_show_input(struct device *dev,
138 				  struct device_attribute *attr, char *buf)
139 {
140 	int nr = to_sensor_dev_attr(attr)->index;
141 	struct i2c_client *client = to_i2c_client(dev);
142 	struct adt7411_data *data = i2c_get_clientdata(client);
143 	int val;
144 	u8 lsb_reg, lsb_shift;
145 
146 	mutex_lock(&data->update_lock);
147 	if (time_after_eq(jiffies, data->next_update)) {
148 		val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
149 		if (val < 0)
150 			goto exit_unlock;
151 
152 		if (val & ADT7411_CFG3_REF_VDD) {
153 			val = adt7411_read_10_bit(client,
154 					ADT7411_REG_INT_TEMP_VDD_LSB,
155 					ADT7411_REG_VDD_MSB, 2);
156 			if (val < 0)
157 				goto exit_unlock;
158 
159 			data->vref_cached = val * 7000 / 1024;
160 		} else {
161 			data->vref_cached = 2250;
162 		}
163 
164 		data->next_update = jiffies + HZ;
165 	}
166 
167 	lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
168 	lsb_shift = 2 * (nr & 0x03);
169 	val = adt7411_read_10_bit(client, lsb_reg,
170 			ADT7411_REG_EXT_TEMP_AIN1_MSB + nr, lsb_shift);
171 	if (val < 0)
172 		goto exit_unlock;
173 
174 	val = sprintf(buf, "%u\n", val * data->vref_cached / 1024);
175  exit_unlock:
176 	mutex_unlock(&data->update_lock);
177 	return val;
178 }
179 
180 static ssize_t adt7411_show_bit(struct device *dev,
181 				struct device_attribute *attr, char *buf)
182 {
183 	struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
184 	struct i2c_client *client = to_i2c_client(dev);
185 	int ret = i2c_smbus_read_byte_data(client, attr2->index);
186 
187 	return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
188 }
189 
190 static ssize_t adt7411_set_bit(struct device *dev,
191 			       struct device_attribute *attr, const char *buf,
192 			       size_t count)
193 {
194 	struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
195 	struct i2c_client *client = to_i2c_client(dev);
196 	struct adt7411_data *data = i2c_get_clientdata(client);
197 	int ret;
198 	unsigned long flag;
199 
200 	ret = kstrtoul(buf, 0, &flag);
201 	if (ret || flag > 1)
202 		return -EINVAL;
203 
204 	ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);
205 
206 	/* force update */
207 	mutex_lock(&data->update_lock);
208 	data->next_update = jiffies;
209 	mutex_unlock(&data->update_lock);
210 
211 	return ret < 0 ? ret : count;
212 }
213 
214 #define ADT7411_BIT_ATTR(__name, __reg, __bit) \
215 	SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \
216 	adt7411_set_bit, __bit, __reg)
217 
218 static DEVICE_ATTR(temp1_input, S_IRUGO, adt7411_show_temp, NULL);
219 static DEVICE_ATTR(in0_input, S_IRUGO, adt7411_show_vdd, NULL);
220 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, adt7411_show_input, NULL, 0);
221 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, adt7411_show_input, NULL, 1);
222 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, adt7411_show_input, NULL, 2);
223 static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, adt7411_show_input, NULL, 3);
224 static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, adt7411_show_input, NULL, 4);
225 static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, adt7411_show_input, NULL, 5);
226 static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, adt7411_show_input, NULL, 6);
227 static SENSOR_DEVICE_ATTR(in8_input, S_IRUGO, adt7411_show_input, NULL, 7);
228 static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
229 static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
230 static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);
231 
232 static struct attribute *adt7411_attrs[] = {
233 	&dev_attr_temp1_input.attr,
234 	&dev_attr_in0_input.attr,
235 	&sensor_dev_attr_in1_input.dev_attr.attr,
236 	&sensor_dev_attr_in2_input.dev_attr.attr,
237 	&sensor_dev_attr_in3_input.dev_attr.attr,
238 	&sensor_dev_attr_in4_input.dev_attr.attr,
239 	&sensor_dev_attr_in5_input.dev_attr.attr,
240 	&sensor_dev_attr_in6_input.dev_attr.attr,
241 	&sensor_dev_attr_in7_input.dev_attr.attr,
242 	&sensor_dev_attr_in8_input.dev_attr.attr,
243 	&sensor_dev_attr_no_average.dev_attr.attr,
244 	&sensor_dev_attr_fast_sampling.dev_attr.attr,
245 	&sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
246 	NULL
247 };
248 
249 static const struct attribute_group adt7411_attr_grp = {
250 	.attrs = adt7411_attrs,
251 };
252 
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, "Wrong manufacturer ID. Got %d, "
264 			"expected %d\n", val, ADT7411_MANUFACTURER_ID);
265 		return -ENODEV;
266 	}
267 
268 	val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
269 	if (val < 0 || val != ADT7411_DEVICE_ID) {
270 		dev_dbg(&client->dev, "Wrong device ID. Got %d, "
271 			"expected %d\n", val, ADT7411_DEVICE_ID);
272 		return -ENODEV;
273 	}
274 
275 	strlcpy(info->type, "adt7411", I2C_NAME_SIZE);
276 
277 	return 0;
278 }
279 
280 static int __devinit adt7411_probe(struct i2c_client *client,
281 				   const struct i2c_device_id *id)
282 {
283 	struct adt7411_data *data;
284 	int ret;
285 
286 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
287 	if (!data)
288 		return -ENOMEM;
289 
290 	i2c_set_clientdata(client, data);
291 	mutex_init(&data->device_lock);
292 	mutex_init(&data->update_lock);
293 
294 	ret = adt7411_modify_bit(client, ADT7411_REG_CFG1,
295 				 ADT7411_CFG1_START_MONITOR, 1);
296 	if (ret < 0)
297 		return ret;
298 
299 	/* force update on first occasion */
300 	data->next_update = jiffies;
301 
302 	ret = sysfs_create_group(&client->dev.kobj, &adt7411_attr_grp);
303 	if (ret)
304 		return ret;
305 
306 	data->hwmon_dev = hwmon_device_register(&client->dev);
307 	if (IS_ERR(data->hwmon_dev)) {
308 		ret = PTR_ERR(data->hwmon_dev);
309 		goto exit_remove;
310 	}
311 
312 	dev_info(&client->dev, "successfully registered\n");
313 
314 	return 0;
315 
316  exit_remove:
317 	sysfs_remove_group(&client->dev.kobj, &adt7411_attr_grp);
318 	return ret;
319 }
320 
321 static int __devexit adt7411_remove(struct i2c_client *client)
322 {
323 	struct adt7411_data *data = i2c_get_clientdata(client);
324 
325 	hwmon_device_unregister(data->hwmon_dev);
326 	sysfs_remove_group(&client->dev.kobj, &adt7411_attr_grp);
327 	return 0;
328 }
329 
330 static const struct i2c_device_id adt7411_id[] = {
331 	{ "adt7411", 0 },
332 	{ }
333 };
334 MODULE_DEVICE_TABLE(i2c, adt7411_id);
335 
336 static struct i2c_driver adt7411_driver = {
337 	.driver		= {
338 		.name		= "adt7411",
339 	},
340 	.probe  = adt7411_probe,
341 	.remove	= __devexit_p(adt7411_remove),
342 	.id_table = adt7411_id,
343 	.detect = adt7411_detect,
344 	.address_list = normal_i2c,
345 	.class = I2C_CLASS_HWMON,
346 };
347 
348 module_i2c_driver(adt7411_driver);
349 
350 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
351 	"Wolfram Sang <w.sang@pengutronix.de>");
352 MODULE_DESCRIPTION("ADT7411 driver");
353 MODULE_LICENSE("GPL v2");
354