Merge branch 'sock_hold-misuses'
[linux/fpc-iii.git] / drivers / hwmon / ad7418.c
bloba01b731ba5d762c15ae18e19153e4b65d9459727
1 /*
2 * An hwmon driver for the Analog Devices AD7416/17/18
3 * Copyright (C) 2006-07 Tower Technologies
5 * Author: Alessandro Zummo <a.zummo@towertech.it>
7 * Based on lm75.c
8 * Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License,
12 * as published by the Free Software Foundation - version 2.
15 #include <linux/module.h>
16 #include <linux/jiffies.h>
17 #include <linux/i2c.h>
18 #include <linux/hwmon.h>
19 #include <linux/hwmon-sysfs.h>
20 #include <linux/err.h>
21 #include <linux/mutex.h>
22 #include <linux/delay.h>
23 #include <linux/slab.h>
25 #include "lm75.h"
27 #define DRV_VERSION "0.4"
29 enum chips { ad7416, ad7417, ad7418 };
31 /* AD7418 registers */
32 #define AD7418_REG_TEMP_IN 0x00
33 #define AD7418_REG_CONF 0x01
34 #define AD7418_REG_TEMP_HYST 0x02
35 #define AD7418_REG_TEMP_OS 0x03
36 #define AD7418_REG_ADC 0x04
37 #define AD7418_REG_CONF2 0x05
39 #define AD7418_REG_ADC_CH(x) ((x) << 5)
40 #define AD7418_CH_TEMP AD7418_REG_ADC_CH(0)
42 static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN,
43 AD7418_REG_TEMP_HYST,
44 AD7418_REG_TEMP_OS };
46 struct ad7418_data {
47 struct i2c_client *client;
48 enum chips type;
49 struct mutex lock;
50 int adc_max; /* number of ADC channels */
51 char valid;
52 unsigned long last_updated; /* In jiffies */
53 s16 temp[3]; /* Register values */
54 u16 in[4];
57 static struct ad7418_data *ad7418_update_device(struct device *dev)
59 struct ad7418_data *data = dev_get_drvdata(dev);
60 struct i2c_client *client = data->client;
62 mutex_lock(&data->lock);
64 if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
65 || !data->valid) {
66 u8 cfg;
67 int i, ch;
69 /* read config register and clear channel bits */
70 cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
71 cfg &= 0x1F;
73 i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
74 cfg | AD7418_CH_TEMP);
75 udelay(30);
77 for (i = 0; i < 3; i++) {
78 data->temp[i] =
79 i2c_smbus_read_word_swapped(client,
80 AD7418_REG_TEMP[i]);
83 for (i = 0, ch = 4; i < data->adc_max; i++, ch--) {
84 i2c_smbus_write_byte_data(client,
85 AD7418_REG_CONF,
86 cfg | AD7418_REG_ADC_CH(ch));
88 udelay(15);
89 data->in[data->adc_max - 1 - i] =
90 i2c_smbus_read_word_swapped(client,
91 AD7418_REG_ADC);
94 /* restore old configuration value */
95 i2c_smbus_write_word_swapped(client, AD7418_REG_CONF, cfg);
97 data->last_updated = jiffies;
98 data->valid = 1;
101 mutex_unlock(&data->lock);
103 return data;
106 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
107 char *buf)
109 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
110 struct ad7418_data *data = ad7418_update_device(dev);
111 return sprintf(buf, "%d\n",
112 LM75_TEMP_FROM_REG(data->temp[attr->index]));
115 static ssize_t show_adc(struct device *dev, struct device_attribute *devattr,
116 char *buf)
118 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
119 struct ad7418_data *data = ad7418_update_device(dev);
121 return sprintf(buf, "%d\n",
122 ((data->in[attr->index] >> 6) * 2500 + 512) / 1024);
125 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
126 const char *buf, size_t count)
128 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
129 struct ad7418_data *data = dev_get_drvdata(dev);
130 struct i2c_client *client = data->client;
131 long temp;
132 int ret = kstrtol(buf, 10, &temp);
134 if (ret < 0)
135 return ret;
137 mutex_lock(&data->lock);
138 data->temp[attr->index] = LM75_TEMP_TO_REG(temp);
139 i2c_smbus_write_word_swapped(client,
140 AD7418_REG_TEMP[attr->index],
141 data->temp[attr->index]);
142 mutex_unlock(&data->lock);
143 return count;
146 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
147 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
148 show_temp, set_temp, 1);
149 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
150 show_temp, set_temp, 2);
152 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_adc, NULL, 0);
153 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_adc, NULL, 1);
154 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_adc, NULL, 2);
155 static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_adc, NULL, 3);
157 static struct attribute *ad7416_attrs[] = {
158 &sensor_dev_attr_temp1_max.dev_attr.attr,
159 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
160 &sensor_dev_attr_temp1_input.dev_attr.attr,
161 NULL
163 ATTRIBUTE_GROUPS(ad7416);
165 static struct attribute *ad7417_attrs[] = {
166 &sensor_dev_attr_temp1_max.dev_attr.attr,
167 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
168 &sensor_dev_attr_temp1_input.dev_attr.attr,
169 &sensor_dev_attr_in1_input.dev_attr.attr,
170 &sensor_dev_attr_in2_input.dev_attr.attr,
171 &sensor_dev_attr_in3_input.dev_attr.attr,
172 &sensor_dev_attr_in4_input.dev_attr.attr,
173 NULL
175 ATTRIBUTE_GROUPS(ad7417);
177 static struct attribute *ad7418_attrs[] = {
178 &sensor_dev_attr_temp1_max.dev_attr.attr,
179 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
180 &sensor_dev_attr_temp1_input.dev_attr.attr,
181 &sensor_dev_attr_in1_input.dev_attr.attr,
182 NULL
184 ATTRIBUTE_GROUPS(ad7418);
186 static void ad7418_init_client(struct i2c_client *client)
188 struct ad7418_data *data = i2c_get_clientdata(client);
190 int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
191 if (reg < 0) {
192 dev_err(&client->dev, "cannot read configuration register\n");
193 } else {
194 dev_info(&client->dev, "configuring for mode 1\n");
195 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe);
197 if (data->type == ad7417 || data->type == ad7418)
198 i2c_smbus_write_byte_data(client,
199 AD7418_REG_CONF2, 0x00);
203 static int ad7418_probe(struct i2c_client *client,
204 const struct i2c_device_id *id)
206 struct device *dev = &client->dev;
207 struct i2c_adapter *adapter = client->adapter;
208 struct ad7418_data *data;
209 struct device *hwmon_dev;
210 const struct attribute_group **attr_groups = NULL;
212 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
213 I2C_FUNC_SMBUS_WORD_DATA))
214 return -EOPNOTSUPP;
216 data = devm_kzalloc(dev, sizeof(struct ad7418_data), GFP_KERNEL);
217 if (!data)
218 return -ENOMEM;
220 i2c_set_clientdata(client, data);
222 mutex_init(&data->lock);
223 data->client = client;
224 data->type = id->driver_data;
226 switch (data->type) {
227 case ad7416:
228 data->adc_max = 0;
229 attr_groups = ad7416_groups;
230 break;
232 case ad7417:
233 data->adc_max = 4;
234 attr_groups = ad7417_groups;
235 break;
237 case ad7418:
238 data->adc_max = 1;
239 attr_groups = ad7418_groups;
240 break;
243 dev_info(dev, "%s chip found\n", client->name);
245 /* Initialize the AD7418 chip */
246 ad7418_init_client(client);
248 hwmon_dev = devm_hwmon_device_register_with_groups(dev,
249 client->name,
250 data, attr_groups);
251 return PTR_ERR_OR_ZERO(hwmon_dev);
254 static const struct i2c_device_id ad7418_id[] = {
255 { "ad7416", ad7416 },
256 { "ad7417", ad7417 },
257 { "ad7418", ad7418 },
260 MODULE_DEVICE_TABLE(i2c, ad7418_id);
262 static struct i2c_driver ad7418_driver = {
263 .driver = {
264 .name = "ad7418",
266 .probe = ad7418_probe,
267 .id_table = ad7418_id,
270 module_i2c_driver(ad7418_driver);
272 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
273 MODULE_DESCRIPTION("AD7416/17/18 driver");
274 MODULE_LICENSE("GPL");
275 MODULE_VERSION(DRV_VERSION);