1 /* 2 * An hwmon driver for the Analog Devices AD7416/17/18 3 * Copyright (C) 2006-07 Tower Technologies 4 * 5 * Author: Alessandro Zummo <a.zummo@towertech.it> 6 * 7 * Based on lm75.c 8 * Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl> 9 * 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. 13 */ 14 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> 24 25 #include "lm75.h" 26 27 #define DRV_VERSION "0.4" 28 29 enum chips { ad7416, ad7417, ad7418 }; 30 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 38 39 #define AD7418_REG_ADC_CH(x) ((x) << 5) 40 #define AD7418_CH_TEMP AD7418_REG_ADC_CH(0) 41 42 static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN, 43 AD7418_REG_TEMP_HYST, 44 AD7418_REG_TEMP_OS }; 45 46 struct ad7418_data { 47 struct device *hwmon_dev; 48 struct attribute_group attrs; 49 enum chips type; 50 struct mutex lock; 51 int adc_max; /* number of ADC channels */ 52 char valid; 53 unsigned long last_updated; /* In jiffies */ 54 s16 temp[3]; /* Register values */ 55 u16 in[4]; 56 }; 57 58 static int ad7418_probe(struct i2c_client *client, 59 const struct i2c_device_id *id); 60 static int ad7418_remove(struct i2c_client *client); 61 62 static const struct i2c_device_id ad7418_id[] = { 63 { "ad7416", ad7416 }, 64 { "ad7417", ad7417 }, 65 { "ad7418", ad7418 }, 66 { } 67 }; 68 MODULE_DEVICE_TABLE(i2c, ad7418_id); 69 70 static struct i2c_driver ad7418_driver = { 71 .driver = { 72 .name = "ad7418", 73 }, 74 .probe = ad7418_probe, 75 .remove = ad7418_remove, 76 .id_table = ad7418_id, 77 }; 78 79 static void ad7418_init_client(struct i2c_client *client) 80 { 81 struct ad7418_data *data = i2c_get_clientdata(client); 82 83 int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 84 if (reg < 0) { 85 dev_err(&client->dev, "cannot read configuration register\n"); 86 } else { 87 dev_info(&client->dev, "configuring for mode 1\n"); 88 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe); 89 90 if (data->type == ad7417 || data->type == ad7418) 91 i2c_smbus_write_byte_data(client, 92 AD7418_REG_CONF2, 0x00); 93 } 94 } 95 96 static struct ad7418_data *ad7418_update_device(struct device *dev) 97 { 98 struct i2c_client *client = to_i2c_client(dev); 99 struct ad7418_data *data = i2c_get_clientdata(client); 100 101 mutex_lock(&data->lock); 102 103 if (time_after(jiffies, data->last_updated + HZ + HZ / 2) 104 || !data->valid) { 105 u8 cfg; 106 int i, ch; 107 108 /* read config register and clear channel bits */ 109 cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 110 cfg &= 0x1F; 111 112 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, 113 cfg | AD7418_CH_TEMP); 114 udelay(30); 115 116 for (i = 0; i < 3; i++) { 117 data->temp[i] = 118 i2c_smbus_read_word_swapped(client, 119 AD7418_REG_TEMP[i]); 120 } 121 122 for (i = 0, ch = 4; i < data->adc_max; i++, ch--) { 123 i2c_smbus_write_byte_data(client, 124 AD7418_REG_CONF, 125 cfg | AD7418_REG_ADC_CH(ch)); 126 127 udelay(15); 128 data->in[data->adc_max - 1 - i] = 129 i2c_smbus_read_word_swapped(client, 130 AD7418_REG_ADC); 131 } 132 133 /* restore old configuration value */ 134 i2c_smbus_write_word_swapped(client, AD7418_REG_CONF, cfg); 135 136 data->last_updated = jiffies; 137 data->valid = 1; 138 } 139 140 mutex_unlock(&data->lock); 141 142 return data; 143 } 144 145 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 146 char *buf) 147 { 148 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 149 struct ad7418_data *data = ad7418_update_device(dev); 150 return sprintf(buf, "%d\n", 151 LM75_TEMP_FROM_REG(data->temp[attr->index])); 152 } 153 154 static ssize_t show_adc(struct device *dev, struct device_attribute *devattr, 155 char *buf) 156 { 157 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 158 struct ad7418_data *data = ad7418_update_device(dev); 159 160 return sprintf(buf, "%d\n", 161 ((data->in[attr->index] >> 6) * 2500 + 512) / 1024); 162 } 163 164 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 165 const char *buf, size_t count) 166 { 167 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 168 struct i2c_client *client = to_i2c_client(dev); 169 struct ad7418_data *data = i2c_get_clientdata(client); 170 long temp = simple_strtol(buf, NULL, 10); 171 172 mutex_lock(&data->lock); 173 data->temp[attr->index] = LM75_TEMP_TO_REG(temp); 174 i2c_smbus_write_word_swapped(client, 175 AD7418_REG_TEMP[attr->index], 176 data->temp[attr->index]); 177 mutex_unlock(&data->lock); 178 return count; 179 } 180 181 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 182 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, 183 show_temp, set_temp, 1); 184 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, 185 show_temp, set_temp, 2); 186 187 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_adc, NULL, 0); 188 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_adc, NULL, 1); 189 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_adc, NULL, 2); 190 static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_adc, NULL, 3); 191 192 static struct attribute *ad7416_attributes[] = { 193 &sensor_dev_attr_temp1_max.dev_attr.attr, 194 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 195 &sensor_dev_attr_temp1_input.dev_attr.attr, 196 NULL 197 }; 198 199 static struct attribute *ad7417_attributes[] = { 200 &sensor_dev_attr_temp1_max.dev_attr.attr, 201 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 202 &sensor_dev_attr_temp1_input.dev_attr.attr, 203 &sensor_dev_attr_in1_input.dev_attr.attr, 204 &sensor_dev_attr_in2_input.dev_attr.attr, 205 &sensor_dev_attr_in3_input.dev_attr.attr, 206 &sensor_dev_attr_in4_input.dev_attr.attr, 207 NULL 208 }; 209 210 static struct attribute *ad7418_attributes[] = { 211 &sensor_dev_attr_temp1_max.dev_attr.attr, 212 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 213 &sensor_dev_attr_temp1_input.dev_attr.attr, 214 &sensor_dev_attr_in1_input.dev_attr.attr, 215 NULL 216 }; 217 218 static int ad7418_probe(struct i2c_client *client, 219 const struct i2c_device_id *id) 220 { 221 struct i2c_adapter *adapter = client->adapter; 222 struct ad7418_data *data; 223 int err; 224 225 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | 226 I2C_FUNC_SMBUS_WORD_DATA)) { 227 err = -EOPNOTSUPP; 228 goto exit; 229 } 230 231 if (!(data = kzalloc(sizeof(struct ad7418_data), GFP_KERNEL))) { 232 err = -ENOMEM; 233 goto exit; 234 } 235 236 i2c_set_clientdata(client, data); 237 238 mutex_init(&data->lock); 239 data->type = id->driver_data; 240 241 switch (data->type) { 242 case ad7416: 243 data->adc_max = 0; 244 data->attrs.attrs = ad7416_attributes; 245 break; 246 247 case ad7417: 248 data->adc_max = 4; 249 data->attrs.attrs = ad7417_attributes; 250 break; 251 252 case ad7418: 253 data->adc_max = 1; 254 data->attrs.attrs = ad7418_attributes; 255 break; 256 } 257 258 dev_info(&client->dev, "%s chip found\n", client->name); 259 260 /* Initialize the AD7418 chip */ 261 ad7418_init_client(client); 262 263 /* Register sysfs hooks */ 264 if ((err = sysfs_create_group(&client->dev.kobj, &data->attrs))) 265 goto exit_free; 266 267 data->hwmon_dev = hwmon_device_register(&client->dev); 268 if (IS_ERR(data->hwmon_dev)) { 269 err = PTR_ERR(data->hwmon_dev); 270 goto exit_remove; 271 } 272 273 return 0; 274 275 exit_remove: 276 sysfs_remove_group(&client->dev.kobj, &data->attrs); 277 exit_free: 278 kfree(data); 279 exit: 280 return err; 281 } 282 283 static int ad7418_remove(struct i2c_client *client) 284 { 285 struct ad7418_data *data = i2c_get_clientdata(client); 286 hwmon_device_unregister(data->hwmon_dev); 287 sysfs_remove_group(&client->dev.kobj, &data->attrs); 288 kfree(data); 289 return 0; 290 } 291 292 static int __init ad7418_init(void) 293 { 294 return i2c_add_driver(&ad7418_driver); 295 } 296 297 static void __exit ad7418_exit(void) 298 { 299 i2c_del_driver(&ad7418_driver); 300 } 301 302 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); 303 MODULE_DESCRIPTION("AD7416/17/18 driver"); 304 MODULE_LICENSE("GPL"); 305 MODULE_VERSION(DRV_VERSION); 306 307 module_init(ad7418_init); 308 module_exit(ad7418_exit); 309