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 29enum 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 42static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN, 43 AD7418_REG_TEMP_HYST, 44 AD7418_REG_TEMP_OS }; 45 46struct 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 58static int ad7418_probe(struct i2c_client *client, 59 const struct i2c_device_id *id); 60static int ad7418_remove(struct i2c_client *client); 61 62static const struct i2c_device_id ad7418_id[] = { 63 { "ad7416", ad7416 }, 64 { "ad7417", ad7417 }, 65 { "ad7418", ad7418 }, 66 { } 67}; 68MODULE_DEVICE_TABLE(i2c, ad7418_id); 69 70static 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/* All registers are word-sized, except for the configuration registers. 80 * AD7418 uses a high-byte first convention. Do NOT use those functions to 81 * access the configuration registers CONF and CONF2, as they are byte-sized. 82 */ 83static inline int ad7418_read(struct i2c_client *client, u8 reg) 84{ 85 return swab16(i2c_smbus_read_word_data(client, reg)); 86} 87 88static inline int ad7418_write(struct i2c_client *client, u8 reg, u16 value) 89{ 90 return i2c_smbus_write_word_data(client, reg, swab16(value)); 91} 92 93static void ad7418_init_client(struct i2c_client *client) 94{ 95 struct ad7418_data *data = i2c_get_clientdata(client); 96 97 int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 98 if (reg < 0) { 99 dev_err(&client->dev, "cannot read configuration register\n"); 100 } else { 101 dev_info(&client->dev, "configuring for mode 1\n"); 102 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe); 103 104 if (data->type == ad7417 || data->type == ad7418) 105 i2c_smbus_write_byte_data(client, 106 AD7418_REG_CONF2, 0x00); 107 } 108} 109 110static struct ad7418_data *ad7418_update_device(struct device *dev) 111{ 112 struct i2c_client *client = to_i2c_client(dev); 113 struct ad7418_data *data = i2c_get_clientdata(client); 114 115 mutex_lock(&data->lock); 116 117 if (time_after(jiffies, data->last_updated + HZ + HZ / 2) 118 || !data->valid) { 119 u8 cfg; 120 int i, ch; 121 122 /* read config register and clear channel bits */ 123 cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 124 cfg &= 0x1F; 125 126 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, 127 cfg | AD7418_CH_TEMP); 128 udelay(30); 129 130 for (i = 0; i < 3; i++) { 131 data->temp[i] = ad7418_read(client, AD7418_REG_TEMP[i]); 132 } 133 134 for (i = 0, ch = 4; i < data->adc_max; i++, ch--) { 135 i2c_smbus_write_byte_data(client, 136 AD7418_REG_CONF, 137 cfg | AD7418_REG_ADC_CH(ch)); 138 139 udelay(15); 140 data->in[data->adc_max - 1 - i] = 141 ad7418_read(client, AD7418_REG_ADC); 142 } 143 144 /* restore old configuration value */ 145 ad7418_write(client, AD7418_REG_CONF, cfg); 146 147 data->last_updated = jiffies; 148 data->valid = 1; 149 } 150 151 mutex_unlock(&data->lock); 152 153 return data; 154} 155 156static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 157 char *buf) 158{ 159 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 160 struct ad7418_data *data = ad7418_update_device(dev); 161 return sprintf(buf, "%d\n", 162 LM75_TEMP_FROM_REG(data->temp[attr->index])); 163} 164 165static ssize_t show_adc(struct device *dev, struct device_attribute *devattr, 166 char *buf) 167{ 168 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 169 struct ad7418_data *data = ad7418_update_device(dev); 170 171 return sprintf(buf, "%d\n", 172 ((data->in[attr->index] >> 6) * 2500 + 512) / 1024); 173} 174 175static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 176 const char *buf, size_t count) 177{ 178 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 179 struct i2c_client *client = to_i2c_client(dev); 180 struct ad7418_data *data = i2c_get_clientdata(client); 181 long temp = simple_strtol(buf, NULL, 10); 182 183 mutex_lock(&data->lock); 184 data->temp[attr->index] = LM75_TEMP_TO_REG(temp); 185 ad7418_write(client, AD7418_REG_TEMP[attr->index], data->temp[attr->index]); 186 mutex_unlock(&data->lock); 187 return count; 188} 189 190static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 191static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, 192 show_temp, set_temp, 1); 193static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, 194 show_temp, set_temp, 2); 195 196static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_adc, NULL, 0); 197static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_adc, NULL, 1); 198static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_adc, NULL, 2); 199static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_adc, NULL, 3); 200 201static struct attribute *ad7416_attributes[] = { 202 &sensor_dev_attr_temp1_max.dev_attr.attr, 203 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 204 &sensor_dev_attr_temp1_input.dev_attr.attr, 205 NULL 206}; 207 208static struct attribute *ad7417_attributes[] = { 209 &sensor_dev_attr_temp1_max.dev_attr.attr, 210 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 211 &sensor_dev_attr_temp1_input.dev_attr.attr, 212 &sensor_dev_attr_in1_input.dev_attr.attr, 213 &sensor_dev_attr_in2_input.dev_attr.attr, 214 &sensor_dev_attr_in3_input.dev_attr.attr, 215 &sensor_dev_attr_in4_input.dev_attr.attr, 216 NULL 217}; 218 219static struct attribute *ad7418_attributes[] = { 220 &sensor_dev_attr_temp1_max.dev_attr.attr, 221 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 222 &sensor_dev_attr_temp1_input.dev_attr.attr, 223 &sensor_dev_attr_in1_input.dev_attr.attr, 224 NULL 225}; 226 227static int ad7418_probe(struct i2c_client *client, 228 const struct i2c_device_id *id) 229{ 230 struct i2c_adapter *adapter = client->adapter; 231 struct ad7418_data *data; 232 int err; 233 234 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | 235 I2C_FUNC_SMBUS_WORD_DATA)) { 236 err = -EOPNOTSUPP; 237 goto exit; 238 } 239 240 if (!(data = kzalloc(sizeof(struct ad7418_data), GFP_KERNEL))) { 241 err = -ENOMEM; 242 goto exit; 243 } 244 245 i2c_set_clientdata(client, data); 246 247 mutex_init(&data->lock); 248 data->type = id->driver_data; 249 250 switch (data->type) { 251 case ad7416: 252 data->adc_max = 0; 253 data->attrs.attrs = ad7416_attributes; 254 break; 255 256 case ad7417: 257 data->adc_max = 4; 258 data->attrs.attrs = ad7417_attributes; 259 break; 260 261 case ad7418: 262 data->adc_max = 1; 263 data->attrs.attrs = ad7418_attributes; 264 break; 265 } 266 267 dev_info(&client->dev, "%s chip found\n", client->name); 268 269 /* Initialize the AD7418 chip */ 270 ad7418_init_client(client); 271 272 /* Register sysfs hooks */ 273 if ((err = sysfs_create_group(&client->dev.kobj, &data->attrs))) 274 goto exit_free; 275 276 data->hwmon_dev = hwmon_device_register(&client->dev); 277 if (IS_ERR(data->hwmon_dev)) { 278 err = PTR_ERR(data->hwmon_dev); 279 goto exit_remove; 280 } 281 282 return 0; 283 284exit_remove: 285 sysfs_remove_group(&client->dev.kobj, &data->attrs); 286exit_free: 287 kfree(data); 288exit: 289 return err; 290} 291 292static int ad7418_remove(struct i2c_client *client) 293{ 294 struct ad7418_data *data = i2c_get_clientdata(client); 295 hwmon_device_unregister(data->hwmon_dev); 296 sysfs_remove_group(&client->dev.kobj, &data->attrs); 297 kfree(data); 298 return 0; 299} 300 301static int __init ad7418_init(void) 302{ 303 return i2c_add_driver(&ad7418_driver); 304} 305 306static void __exit ad7418_exit(void) 307{ 308 i2c_del_driver(&ad7418_driver); 309} 310 311MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); 312MODULE_DESCRIPTION("AD7416/17/18 driver"); 313MODULE_LICENSE("GPL"); 314MODULE_VERSION(DRV_VERSION); 315 316module_init(ad7418_init); 317module_exit(ad7418_exit); 318