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 24 #include "lm75.h" 25 26 #define DRV_VERSION "0.4" 27 28 enum chips { ad7416, ad7417, ad7418 }; 29 30 /* AD7418 registers */ 31 #define AD7418_REG_TEMP_IN 0x00 32 #define AD7418_REG_CONF 0x01 33 #define AD7418_REG_TEMP_HYST 0x02 34 #define AD7418_REG_TEMP_OS 0x03 35 #define AD7418_REG_ADC 0x04 36 #define AD7418_REG_CONF2 0x05 37 38 #define AD7418_REG_ADC_CH(x) ((x) << 5) 39 #define AD7418_CH_TEMP AD7418_REG_ADC_CH(0) 40 41 static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN, 42 AD7418_REG_TEMP_HYST, 43 AD7418_REG_TEMP_OS }; 44 45 struct ad7418_data { 46 struct device *hwmon_dev; 47 struct attribute_group attrs; 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]; 55 }; 56 57 static int ad7418_probe(struct i2c_client *client, 58 const struct i2c_device_id *id); 59 static int ad7418_remove(struct i2c_client *client); 60 61 static const struct i2c_device_id ad7418_id[] = { 62 { "ad7416", ad7416 }, 63 { "ad7417", ad7417 }, 64 { "ad7418", ad7418 }, 65 { } 66 }; 67 MODULE_DEVICE_TABLE(i2c, ad7418_id); 68 69 static struct i2c_driver ad7418_driver = { 70 .driver = { 71 .name = "ad7418", 72 }, 73 .probe = ad7418_probe, 74 .remove = ad7418_remove, 75 .id_table = ad7418_id, 76 }; 77 78 /* All registers are word-sized, except for the configuration registers. 79 * AD7418 uses a high-byte first convention. Do NOT use those functions to 80 * access the configuration registers CONF and CONF2, as they are byte-sized. 81 */ 82 static inline int ad7418_read(struct i2c_client *client, u8 reg) 83 { 84 return swab16(i2c_smbus_read_word_data(client, reg)); 85 } 86 87 static inline int ad7418_write(struct i2c_client *client, u8 reg, u16 value) 88 { 89 return i2c_smbus_write_word_data(client, reg, swab16(value)); 90 } 91 92 static void ad7418_init_client(struct i2c_client *client) 93 { 94 struct ad7418_data *data = i2c_get_clientdata(client); 95 96 int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 97 if (reg < 0) { 98 dev_err(&client->dev, "cannot read configuration register\n"); 99 } else { 100 dev_info(&client->dev, "configuring for mode 1\n"); 101 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe); 102 103 if (data->type == ad7417 || data->type == ad7418) 104 i2c_smbus_write_byte_data(client, 105 AD7418_REG_CONF2, 0x00); 106 } 107 } 108 109 static struct ad7418_data *ad7418_update_device(struct device *dev) 110 { 111 struct i2c_client *client = to_i2c_client(dev); 112 struct ad7418_data *data = i2c_get_clientdata(client); 113 114 mutex_lock(&data->lock); 115 116 if (time_after(jiffies, data->last_updated + HZ + HZ / 2) 117 || !data->valid) { 118 u8 cfg; 119 int i, ch; 120 121 /* read config register and clear channel bits */ 122 cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 123 cfg &= 0x1F; 124 125 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, 126 cfg | AD7418_CH_TEMP); 127 udelay(30); 128 129 for (i = 0; i < 3; i++) { 130 data->temp[i] = ad7418_read(client, AD7418_REG_TEMP[i]); 131 } 132 133 for (i = 0, ch = 4; i < data->adc_max; i++, ch--) { 134 i2c_smbus_write_byte_data(client, 135 AD7418_REG_CONF, 136 cfg | AD7418_REG_ADC_CH(ch)); 137 138 udelay(15); 139 data->in[data->adc_max - 1 - i] = 140 ad7418_read(client, AD7418_REG_ADC); 141 } 142 143 /* restore old configuration value */ 144 ad7418_write(client, AD7418_REG_CONF, cfg); 145 146 data->last_updated = jiffies; 147 data->valid = 1; 148 } 149 150 mutex_unlock(&data->lock); 151 152 return data; 153 } 154 155 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 156 char *buf) 157 { 158 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 159 struct ad7418_data *data = ad7418_update_device(dev); 160 return sprintf(buf, "%d\n", 161 LM75_TEMP_FROM_REG(data->temp[attr->index])); 162 } 163 164 static ssize_t show_adc(struct device *dev, struct device_attribute *devattr, 165 char *buf) 166 { 167 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 168 struct ad7418_data *data = ad7418_update_device(dev); 169 170 return sprintf(buf, "%d\n", 171 ((data->in[attr->index] >> 6) * 2500 + 512) / 1024); 172 } 173 174 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 175 const char *buf, size_t count) 176 { 177 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 178 struct i2c_client *client = to_i2c_client(dev); 179 struct ad7418_data *data = i2c_get_clientdata(client); 180 long temp = simple_strtol(buf, NULL, 10); 181 182 mutex_lock(&data->lock); 183 data->temp[attr->index] = LM75_TEMP_TO_REG(temp); 184 ad7418_write(client, AD7418_REG_TEMP[attr->index], data->temp[attr->index]); 185 mutex_unlock(&data->lock); 186 return count; 187 } 188 189 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 190 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, 191 show_temp, set_temp, 1); 192 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, 193 show_temp, set_temp, 2); 194 195 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_adc, NULL, 0); 196 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_adc, NULL, 1); 197 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_adc, NULL, 2); 198 static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_adc, NULL, 3); 199 200 static struct attribute *ad7416_attributes[] = { 201 &sensor_dev_attr_temp1_max.dev_attr.attr, 202 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 203 &sensor_dev_attr_temp1_input.dev_attr.attr, 204 NULL 205 }; 206 207 static struct attribute *ad7417_attributes[] = { 208 &sensor_dev_attr_temp1_max.dev_attr.attr, 209 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 210 &sensor_dev_attr_temp1_input.dev_attr.attr, 211 &sensor_dev_attr_in1_input.dev_attr.attr, 212 &sensor_dev_attr_in2_input.dev_attr.attr, 213 &sensor_dev_attr_in3_input.dev_attr.attr, 214 &sensor_dev_attr_in4_input.dev_attr.attr, 215 NULL 216 }; 217 218 static struct attribute *ad7418_attributes[] = { 219 &sensor_dev_attr_temp1_max.dev_attr.attr, 220 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 221 &sensor_dev_attr_temp1_input.dev_attr.attr, 222 &sensor_dev_attr_in1_input.dev_attr.attr, 223 NULL 224 }; 225 226 static int ad7418_probe(struct i2c_client *client, 227 const struct i2c_device_id *id) 228 { 229 struct i2c_adapter *adapter = client->adapter; 230 struct ad7418_data *data; 231 int err; 232 233 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | 234 I2C_FUNC_SMBUS_WORD_DATA)) { 235 err = -EOPNOTSUPP; 236 goto exit; 237 } 238 239 if (!(data = kzalloc(sizeof(struct ad7418_data), GFP_KERNEL))) { 240 err = -ENOMEM; 241 goto exit; 242 } 243 244 i2c_set_clientdata(client, data); 245 246 mutex_init(&data->lock); 247 data->type = id->driver_data; 248 249 switch (data->type) { 250 case ad7416: 251 data->adc_max = 0; 252 data->attrs.attrs = ad7416_attributes; 253 break; 254 255 case ad7417: 256 data->adc_max = 4; 257 data->attrs.attrs = ad7417_attributes; 258 break; 259 260 case ad7418: 261 data->adc_max = 1; 262 data->attrs.attrs = ad7418_attributes; 263 break; 264 } 265 266 dev_info(&client->dev, "%s chip found\n", client->name); 267 268 /* Initialize the AD7418 chip */ 269 ad7418_init_client(client); 270 271 /* Register sysfs hooks */ 272 if ((err = sysfs_create_group(&client->dev.kobj, &data->attrs))) 273 goto exit_free; 274 275 data->hwmon_dev = hwmon_device_register(&client->dev); 276 if (IS_ERR(data->hwmon_dev)) { 277 err = PTR_ERR(data->hwmon_dev); 278 goto exit_remove; 279 } 280 281 return 0; 282 283 exit_remove: 284 sysfs_remove_group(&client->dev.kobj, &data->attrs); 285 exit_free: 286 kfree(data); 287 exit: 288 return err; 289 } 290 291 static int ad7418_remove(struct i2c_client *client) 292 { 293 struct ad7418_data *data = i2c_get_clientdata(client); 294 hwmon_device_unregister(data->hwmon_dev); 295 sysfs_remove_group(&client->dev.kobj, &data->attrs); 296 kfree(data); 297 return 0; 298 } 299 300 static int __init ad7418_init(void) 301 { 302 return i2c_add_driver(&ad7418_driver); 303 } 304 305 static void __exit ad7418_exit(void) 306 { 307 i2c_del_driver(&ad7418_driver); 308 } 309 310 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); 311 MODULE_DESCRIPTION("AD7416/17/18 driver"); 312 MODULE_LICENSE("GPL"); 313 MODULE_VERSION(DRV_VERSION); 314 315 module_init(ad7418_init); 316 module_exit(ad7418_exit); 317