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 "0.3" 27 28 /* Addresses to scan */ 29 static unsigned short normal_i2c[] = { 0x28, I2C_CLIENT_END }; 30 /* Insmod parameters */ 31 I2C_CLIENT_INSMOD_3(ad7416, ad7417, ad7418); 32 33 /* AD7418 registers */ 34 #define AD7418_REG_TEMP_IN 0x00 35 #define AD7418_REG_CONF 0x01 36 #define AD7418_REG_TEMP_HYST 0x02 37 #define AD7418_REG_TEMP_OS 0x03 38 #define AD7418_REG_ADC 0x04 39 #define AD7418_REG_CONF2 0x05 40 41 #define AD7418_REG_ADC_CH(x) ((x) << 5) 42 #define AD7418_CH_TEMP AD7418_REG_ADC_CH(0) 43 44 static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN, 45 AD7418_REG_TEMP_HYST, 46 AD7418_REG_TEMP_OS }; 47 48 struct ad7418_data { 49 struct i2c_client client; 50 struct class_device *class_dev; 51 struct attribute_group attrs; 52 enum chips type; 53 struct mutex lock; 54 int adc_max; /* number of ADC channels */ 55 char valid; 56 unsigned long last_updated; /* In jiffies */ 57 s16 temp[3]; /* Register values */ 58 u16 in[4]; 59 }; 60 61 static int ad7418_attach_adapter(struct i2c_adapter *adapter); 62 static int ad7418_detect(struct i2c_adapter *adapter, int address, int kind); 63 static int ad7418_detach_client(struct i2c_client *client); 64 65 static struct i2c_driver ad7418_driver = { 66 .driver = { 67 .name = "ad7418", 68 }, 69 .attach_adapter = ad7418_attach_adapter, 70 .detach_client = ad7418_detach_client, 71 }; 72 73 /* All registers are word-sized, except for the configuration registers. 74 * AD7418 uses a high-byte first convention. Do NOT use those functions to 75 * access the configuration registers CONF and CONF2, as they are byte-sized. 76 */ 77 static inline int ad7418_read(struct i2c_client *client, u8 reg) 78 { 79 return swab16(i2c_smbus_read_word_data(client, reg)); 80 } 81 82 static inline int ad7418_write(struct i2c_client *client, u8 reg, u16 value) 83 { 84 return i2c_smbus_write_word_data(client, reg, swab16(value)); 85 } 86 87 static void ad7418_init_client(struct i2c_client *client) 88 { 89 struct ad7418_data *data = i2c_get_clientdata(client); 90 91 int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 92 if (reg < 0) { 93 dev_err(&client->dev, "cannot read configuration register\n"); 94 } else { 95 dev_info(&client->dev, "configuring for mode 1\n"); 96 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe); 97 98 if (data->type == ad7417 || data->type == ad7418) 99 i2c_smbus_write_byte_data(client, 100 AD7418_REG_CONF2, 0x00); 101 } 102 } 103 104 static struct ad7418_data *ad7418_update_device(struct device *dev) 105 { 106 struct i2c_client *client = to_i2c_client(dev); 107 struct ad7418_data *data = i2c_get_clientdata(client); 108 109 mutex_lock(&data->lock); 110 111 if (time_after(jiffies, data->last_updated + HZ + HZ / 2) 112 || !data->valid) { 113 u8 cfg; 114 int i, ch; 115 116 /* read config register and clear channel bits */ 117 cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 118 cfg &= 0x1F; 119 120 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, 121 cfg | AD7418_CH_TEMP); 122 udelay(30); 123 124 for (i = 0; i < 3; i++) { 125 data->temp[i] = ad7418_read(client, AD7418_REG_TEMP[i]); 126 } 127 128 for (i = 0, ch = 4; i < data->adc_max; i++, ch--) { 129 i2c_smbus_write_byte_data(client, 130 AD7418_REG_CONF, 131 cfg | AD7418_REG_ADC_CH(ch)); 132 133 udelay(15); 134 data->in[data->adc_max - 1 - i] = 135 ad7418_read(client, AD7418_REG_ADC); 136 } 137 138 /* restore old configuration value */ 139 ad7418_write(client, AD7418_REG_CONF, cfg); 140 141 data->last_updated = jiffies; 142 data->valid = 1; 143 } 144 145 mutex_unlock(&data->lock); 146 147 return data; 148 } 149 150 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 151 char *buf) 152 { 153 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 154 struct ad7418_data *data = ad7418_update_device(dev); 155 return sprintf(buf, "%d\n", 156 LM75_TEMP_FROM_REG(data->temp[attr->index])); 157 } 158 159 static ssize_t show_adc(struct device *dev, struct device_attribute *devattr, 160 char *buf) 161 { 162 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 163 struct ad7418_data *data = ad7418_update_device(dev); 164 165 return sprintf(buf, "%d\n", 166 ((data->in[attr->index] >> 6) * 2500 + 512) / 1024); 167 } 168 169 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 170 const char *buf, size_t count) 171 { 172 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 173 struct i2c_client *client = to_i2c_client(dev); 174 struct ad7418_data *data = i2c_get_clientdata(client); 175 int temp = simple_strtol(buf, NULL, 10); 176 177 mutex_lock(&data->lock); 178 data->temp[attr->index] = LM75_TEMP_TO_REG(temp); 179 ad7418_write(client, AD7418_REG_TEMP[attr->index], data->temp[attr->index]); 180 mutex_unlock(&data->lock); 181 return count; 182 } 183 184 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 185 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, 186 show_temp, set_temp, 1); 187 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, 188 show_temp, set_temp, 2); 189 190 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_adc, NULL, 0); 191 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_adc, NULL, 1); 192 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_adc, NULL, 2); 193 static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_adc, NULL, 3); 194 195 static int ad7418_attach_adapter(struct i2c_adapter *adapter) 196 { 197 if (!(adapter->class & I2C_CLASS_HWMON)) 198 return 0; 199 return i2c_probe(adapter, &addr_data, ad7418_detect); 200 } 201 202 static struct attribute *ad7416_attributes[] = { 203 &sensor_dev_attr_temp1_max.dev_attr.attr, 204 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 205 &sensor_dev_attr_temp1_input.dev_attr.attr, 206 NULL 207 }; 208 209 static struct attribute *ad7417_attributes[] = { 210 &sensor_dev_attr_temp1_max.dev_attr.attr, 211 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 212 &sensor_dev_attr_temp1_input.dev_attr.attr, 213 &sensor_dev_attr_in1_input.dev_attr.attr, 214 &sensor_dev_attr_in2_input.dev_attr.attr, 215 &sensor_dev_attr_in3_input.dev_attr.attr, 216 &sensor_dev_attr_in4_input.dev_attr.attr, 217 NULL 218 }; 219 220 static struct attribute *ad7418_attributes[] = { 221 &sensor_dev_attr_temp1_max.dev_attr.attr, 222 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 223 &sensor_dev_attr_temp1_input.dev_attr.attr, 224 &sensor_dev_attr_in1_input.dev_attr.attr, 225 NULL 226 }; 227 228 static int ad7418_detect(struct i2c_adapter *adapter, int address, int kind) 229 { 230 struct i2c_client *client; 231 struct ad7418_data *data; 232 int err = 0; 233 234 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | 235 I2C_FUNC_SMBUS_WORD_DATA)) 236 goto exit; 237 238 if (!(data = kzalloc(sizeof(struct ad7418_data), GFP_KERNEL))) { 239 err = -ENOMEM; 240 goto exit; 241 } 242 243 client = &data->client; 244 client->addr = address; 245 client->adapter = adapter; 246 client->driver = &ad7418_driver; 247 248 i2c_set_clientdata(client, data); 249 250 mutex_init(&data->lock); 251 252 /* AD7418 has a curious behaviour on registers 6 and 7. They 253 * both always read 0xC071 and are not documented on the datasheet. 254 * We use them to detect the chip. 255 */ 256 if (kind <= 0) { 257 int reg, reg6, reg7; 258 259 /* the AD7416 lies within this address range, but I have 260 * no means to check. 261 */ 262 if (address >= 0x48 && address <= 0x4f) { 263 /* XXX add tests for AD7416 here */ 264 /* data->type = ad7416; */ 265 } 266 /* here we might have AD7417 or AD7418 */ 267 else if (address >= 0x28 && address <= 0x2f) { 268 reg6 = i2c_smbus_read_word_data(client, 0x06); 269 reg7 = i2c_smbus_read_word_data(client, 0x07); 270 271 if (address == 0x28 && reg6 == 0xC071 && reg7 == 0xC071) 272 data->type = ad7418; 273 274 /* XXX add tests for AD7417 here */ 275 276 277 /* both AD7417 and AD7418 have bits 0-5 of 278 * the CONF2 register at 0 279 */ 280 reg = i2c_smbus_read_byte_data(client, 281 AD7418_REG_CONF2); 282 if (reg & 0x3F) 283 data->type = any_chip; /* detection failed */ 284 } 285 } else { 286 dev_dbg(&adapter->dev, "detection forced\n"); 287 } 288 289 if (kind > 0) 290 data->type = kind; 291 else if (kind < 0 && data->type == any_chip) { 292 err = -ENODEV; 293 goto exit_free; 294 } 295 296 switch (data->type) { 297 case any_chip: 298 case ad7416: 299 data->adc_max = 0; 300 data->attrs.attrs = ad7416_attributes; 301 strlcpy(client->name, "ad7416", I2C_NAME_SIZE); 302 break; 303 304 case ad7417: 305 data->adc_max = 4; 306 data->attrs.attrs = ad7417_attributes; 307 strlcpy(client->name, "ad7417", I2C_NAME_SIZE); 308 break; 309 310 case ad7418: 311 data->adc_max = 1; 312 data->attrs.attrs = ad7418_attributes; 313 strlcpy(client->name, "ad7418", I2C_NAME_SIZE); 314 break; 315 } 316 317 if ((err = i2c_attach_client(client))) 318 goto exit_free; 319 320 dev_info(&client->dev, "%s chip found\n", client->name); 321 322 /* Initialize the AD7418 chip */ 323 ad7418_init_client(client); 324 325 /* Register sysfs hooks */ 326 if ((err = sysfs_create_group(&client->dev.kobj, &data->attrs))) 327 goto exit_detach; 328 329 data->class_dev = hwmon_device_register(&client->dev); 330 if (IS_ERR(data->class_dev)) { 331 err = PTR_ERR(data->class_dev); 332 goto exit_remove; 333 } 334 335 return 0; 336 337 exit_remove: 338 sysfs_remove_group(&client->dev.kobj, &data->attrs); 339 exit_detach: 340 i2c_detach_client(client); 341 exit_free: 342 kfree(data); 343 exit: 344 return err; 345 } 346 347 static int ad7418_detach_client(struct i2c_client *client) 348 { 349 struct ad7418_data *data = i2c_get_clientdata(client); 350 hwmon_device_unregister(data->class_dev); 351 sysfs_remove_group(&client->dev.kobj, &data->attrs); 352 i2c_detach_client(client); 353 kfree(data); 354 return 0; 355 } 356 357 static int __init ad7418_init(void) 358 { 359 return i2c_add_driver(&ad7418_driver); 360 } 361 362 static void __exit ad7418_exit(void) 363 { 364 i2c_del_driver(&ad7418_driver); 365 } 366 367 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); 368 MODULE_DESCRIPTION("AD7416/17/18 driver"); 369 MODULE_LICENSE("GPL"); 370 MODULE_VERSION(DRV_VERSION); 371 372 module_init(ad7418_init); 373 module_exit(ad7418_exit); 374