1 /* 2 * Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor) 3 * 4 * Copyright (C) 2008, 2010 Pengutronix 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 * 10 * TODO: SPI, use power-down mode for suspend?, interrupt handling? 11 */ 12 13 #include <linux/kernel.h> 14 #include <linux/module.h> 15 #include <linux/init.h> 16 #include <linux/err.h> 17 #include <linux/mutex.h> 18 #include <linux/jiffies.h> 19 #include <linux/i2c.h> 20 #include <linux/hwmon.h> 21 #include <linux/hwmon-sysfs.h> 22 #include <linux/slab.h> 23 24 #define ADT7411_REG_INT_TEMP_VDD_LSB 0x03 25 #define ADT7411_REG_EXT_TEMP_AIN14_LSB 0x04 26 #define ADT7411_REG_VDD_MSB 0x06 27 #define ADT7411_REG_INT_TEMP_MSB 0x07 28 #define ADT7411_REG_EXT_TEMP_AIN1_MSB 0x08 29 30 #define ADT7411_REG_CFG1 0x18 31 #define ADT7411_CFG1_START_MONITOR (1 << 0) 32 #define ADT7411_CFG1_RESERVED_BIT1 (1 << 1) 33 #define ADT7411_CFG1_EXT_TDM (1 << 2) 34 #define ADT7411_CFG1_RESERVED_BIT3 (1 << 3) 35 36 #define ADT7411_REG_CFG2 0x19 37 #define ADT7411_CFG2_DISABLE_AVG (1 << 5) 38 39 #define ADT7411_REG_CFG3 0x1a 40 #define ADT7411_CFG3_ADC_CLK_225 (1 << 0) 41 #define ADT7411_CFG3_RESERVED_BIT1 (1 << 1) 42 #define ADT7411_CFG3_RESERVED_BIT2 (1 << 2) 43 #define ADT7411_CFG3_RESERVED_BIT3 (1 << 3) 44 #define ADT7411_CFG3_REF_VDD (1 << 4) 45 46 #define ADT7411_REG_DEVICE_ID 0x4d 47 #define ADT7411_REG_MANUFACTURER_ID 0x4e 48 49 #define ADT7411_DEVICE_ID 0x2 50 #define ADT7411_MANUFACTURER_ID 0x41 51 52 static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END }; 53 54 struct adt7411_data { 55 struct mutex device_lock; /* for "atomic" device accesses */ 56 struct mutex update_lock; 57 unsigned long next_update; 58 int vref_cached; 59 struct i2c_client *client; 60 bool use_ext_temp; 61 }; 62 63 /* 64 * When reading a register containing (up to 4) lsb, all associated 65 * msb-registers get locked by the hardware. After _one_ of those msb is read, 66 * _all_ are unlocked. In order to use this locking correctly, reading lsb/msb 67 * is protected here with a mutex, too. 68 */ 69 static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg, 70 u8 msb_reg, u8 lsb_shift) 71 { 72 struct adt7411_data *data = i2c_get_clientdata(client); 73 int val, tmp; 74 75 mutex_lock(&data->device_lock); 76 77 val = i2c_smbus_read_byte_data(client, lsb_reg); 78 if (val < 0) 79 goto exit_unlock; 80 81 tmp = (val >> lsb_shift) & 3; 82 val = i2c_smbus_read_byte_data(client, msb_reg); 83 84 if (val >= 0) 85 val = (val << 2) | tmp; 86 87 exit_unlock: 88 mutex_unlock(&data->device_lock); 89 90 return val; 91 } 92 93 static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit, 94 bool flag) 95 { 96 struct adt7411_data *data = i2c_get_clientdata(client); 97 int ret, val; 98 99 mutex_lock(&data->device_lock); 100 101 ret = i2c_smbus_read_byte_data(client, reg); 102 if (ret < 0) 103 goto exit_unlock; 104 105 if (flag) 106 val = ret | bit; 107 else 108 val = ret & ~bit; 109 110 ret = i2c_smbus_write_byte_data(client, reg, val); 111 112 exit_unlock: 113 mutex_unlock(&data->device_lock); 114 return ret; 115 } 116 117 static ssize_t adt7411_show_vdd(struct device *dev, 118 struct device_attribute *attr, char *buf) 119 { 120 struct adt7411_data *data = dev_get_drvdata(dev); 121 struct i2c_client *client = data->client; 122 int ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB, 123 ADT7411_REG_VDD_MSB, 2); 124 125 return ret < 0 ? ret : sprintf(buf, "%u\n", ret * 7000 / 1024); 126 } 127 128 static ssize_t adt7411_show_temp(struct device *dev, 129 struct device_attribute *attr, char *buf) 130 { 131 int nr = to_sensor_dev_attr(attr)->index; 132 struct adt7411_data *data = dev_get_drvdata(dev); 133 struct i2c_client *client = data->client; 134 int val; 135 struct { 136 u8 low; 137 u8 high; 138 } reg[2] = { 139 { ADT7411_REG_INT_TEMP_VDD_LSB, ADT7411_REG_INT_TEMP_MSB }, 140 { ADT7411_REG_EXT_TEMP_AIN14_LSB, 141 ADT7411_REG_EXT_TEMP_AIN1_MSB }, 142 }; 143 144 val = adt7411_read_10_bit(client, reg[nr].low, reg[nr].high, 0); 145 if (val < 0) 146 return val; 147 148 val = val & 0x200 ? val - 0x400 : val; /* 10 bit signed */ 149 150 return sprintf(buf, "%d\n", val * 250); 151 } 152 153 static ssize_t adt7411_show_input(struct device *dev, 154 struct device_attribute *attr, char *buf) 155 { 156 int nr = to_sensor_dev_attr(attr)->index; 157 struct adt7411_data *data = dev_get_drvdata(dev); 158 struct i2c_client *client = data->client; 159 int val; 160 u8 lsb_reg, lsb_shift; 161 162 mutex_lock(&data->update_lock); 163 if (time_after_eq(jiffies, data->next_update)) { 164 val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3); 165 if (val < 0) 166 goto exit_unlock; 167 168 if (val & ADT7411_CFG3_REF_VDD) { 169 val = adt7411_read_10_bit(client, 170 ADT7411_REG_INT_TEMP_VDD_LSB, 171 ADT7411_REG_VDD_MSB, 2); 172 if (val < 0) 173 goto exit_unlock; 174 175 data->vref_cached = val * 7000 / 1024; 176 } else { 177 data->vref_cached = 2250; 178 } 179 180 data->next_update = jiffies + HZ; 181 } 182 183 lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2); 184 lsb_shift = 2 * (nr & 0x03); 185 val = adt7411_read_10_bit(client, lsb_reg, 186 ADT7411_REG_EXT_TEMP_AIN1_MSB + nr, lsb_shift); 187 if (val < 0) 188 goto exit_unlock; 189 190 val = sprintf(buf, "%u\n", val * data->vref_cached / 1024); 191 exit_unlock: 192 mutex_unlock(&data->update_lock); 193 return val; 194 } 195 196 static ssize_t adt7411_show_bit(struct device *dev, 197 struct device_attribute *attr, char *buf) 198 { 199 struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr); 200 struct adt7411_data *data = dev_get_drvdata(dev); 201 struct i2c_client *client = data->client; 202 int ret = i2c_smbus_read_byte_data(client, attr2->index); 203 204 return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr)); 205 } 206 207 static ssize_t adt7411_set_bit(struct device *dev, 208 struct device_attribute *attr, const char *buf, 209 size_t count) 210 { 211 struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr); 212 struct adt7411_data *data = dev_get_drvdata(dev); 213 struct i2c_client *client = data->client; 214 int ret; 215 unsigned long flag; 216 217 ret = kstrtoul(buf, 0, &flag); 218 if (ret || flag > 1) 219 return -EINVAL; 220 221 ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag); 222 223 /* force update */ 224 mutex_lock(&data->update_lock); 225 data->next_update = jiffies; 226 mutex_unlock(&data->update_lock); 227 228 return ret < 0 ? ret : count; 229 } 230 231 232 #define ADT7411_BIT_ATTR(__name, __reg, __bit) \ 233 SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \ 234 adt7411_set_bit, __bit, __reg) 235 236 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adt7411_show_temp, NULL, 0); 237 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, adt7411_show_temp, NULL, 1); 238 static DEVICE_ATTR(in0_input, S_IRUGO, adt7411_show_vdd, NULL); 239 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, adt7411_show_input, NULL, 0); 240 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, adt7411_show_input, NULL, 1); 241 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, adt7411_show_input, NULL, 2); 242 static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, adt7411_show_input, NULL, 3); 243 static SENSOR_DEVICE_ATTR(in5_input, S_IRUGO, adt7411_show_input, NULL, 4); 244 static SENSOR_DEVICE_ATTR(in6_input, S_IRUGO, adt7411_show_input, NULL, 5); 245 static SENSOR_DEVICE_ATTR(in7_input, S_IRUGO, adt7411_show_input, NULL, 6); 246 static SENSOR_DEVICE_ATTR(in8_input, S_IRUGO, adt7411_show_input, NULL, 7); 247 static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG); 248 static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225); 249 static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD); 250 251 static struct attribute *adt7411_attrs[] = { 252 &sensor_dev_attr_temp1_input.dev_attr.attr, 253 &sensor_dev_attr_temp2_input.dev_attr.attr, 254 &dev_attr_in0_input.attr, 255 &sensor_dev_attr_in1_input.dev_attr.attr, 256 &sensor_dev_attr_in2_input.dev_attr.attr, 257 &sensor_dev_attr_in3_input.dev_attr.attr, 258 &sensor_dev_attr_in4_input.dev_attr.attr, 259 &sensor_dev_attr_in5_input.dev_attr.attr, 260 &sensor_dev_attr_in6_input.dev_attr.attr, 261 &sensor_dev_attr_in7_input.dev_attr.attr, 262 &sensor_dev_attr_in8_input.dev_attr.attr, 263 &sensor_dev_attr_no_average.dev_attr.attr, 264 &sensor_dev_attr_fast_sampling.dev_attr.attr, 265 &sensor_dev_attr_adc_ref_vdd.dev_attr.attr, 266 NULL 267 }; 268 269 static umode_t adt7411_attrs_visible(struct kobject *kobj, 270 struct attribute *attr, int index) 271 { 272 struct device *dev = container_of(kobj, struct device, kobj); 273 struct adt7411_data *data = dev_get_drvdata(dev); 274 bool visible = true; 275 276 if (attr == &sensor_dev_attr_temp2_input.dev_attr.attr) 277 visible = data->use_ext_temp; 278 else if (attr == &sensor_dev_attr_in1_input.dev_attr.attr || 279 attr == &sensor_dev_attr_in2_input.dev_attr.attr) 280 visible = !data->use_ext_temp; 281 282 return visible ? attr->mode : 0; 283 } 284 285 static const struct attribute_group adt7411_group = { 286 .attrs = adt7411_attrs, 287 .is_visible = adt7411_attrs_visible, 288 }; 289 __ATTRIBUTE_GROUPS(adt7411); 290 291 static int adt7411_detect(struct i2c_client *client, 292 struct i2c_board_info *info) 293 { 294 int val; 295 296 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 297 return -ENODEV; 298 299 val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID); 300 if (val < 0 || val != ADT7411_MANUFACTURER_ID) { 301 dev_dbg(&client->dev, 302 "Wrong manufacturer ID. Got %d, expected %d\n", 303 val, ADT7411_MANUFACTURER_ID); 304 return -ENODEV; 305 } 306 307 val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID); 308 if (val < 0 || val != ADT7411_DEVICE_ID) { 309 dev_dbg(&client->dev, 310 "Wrong device ID. Got %d, expected %d\n", 311 val, ADT7411_DEVICE_ID); 312 return -ENODEV; 313 } 314 315 strlcpy(info->type, "adt7411", I2C_NAME_SIZE); 316 317 return 0; 318 } 319 320 static int adt7411_init_device(struct adt7411_data *data) 321 { 322 int ret; 323 u8 val; 324 325 ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG3); 326 if (ret < 0) 327 return ret; 328 329 /* 330 * We must only write zero to bit 1 and bit 2 and only one to bit 3 331 * according to the datasheet. 332 */ 333 val = ret; 334 val &= ~(ADT7411_CFG3_RESERVED_BIT1 | ADT7411_CFG3_RESERVED_BIT2); 335 val |= ADT7411_CFG3_RESERVED_BIT3; 336 337 ret = i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG3, val); 338 if (ret < 0) 339 return ret; 340 341 ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG1); 342 if (ret < 0) 343 return ret; 344 345 data->use_ext_temp = ret & ADT7411_CFG1_EXT_TDM; 346 347 /* 348 * We must only write zero to bit 1 and only one to bit 3 according to 349 * the datasheet. 350 */ 351 val = ret; 352 val &= ~ADT7411_CFG1_RESERVED_BIT1; 353 val |= ADT7411_CFG1_RESERVED_BIT3; 354 355 /* enable monitoring */ 356 val |= ADT7411_CFG1_START_MONITOR; 357 358 return i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG1, val); 359 } 360 361 static int adt7411_probe(struct i2c_client *client, 362 const struct i2c_device_id *id) 363 { 364 struct device *dev = &client->dev; 365 struct adt7411_data *data; 366 struct device *hwmon_dev; 367 int ret; 368 369 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 370 if (!data) 371 return -ENOMEM; 372 373 i2c_set_clientdata(client, data); 374 data->client = client; 375 mutex_init(&data->device_lock); 376 mutex_init(&data->update_lock); 377 378 ret = adt7411_init_device(data); 379 if (ret < 0) 380 return ret; 381 382 /* force update on first occasion */ 383 data->next_update = jiffies; 384 385 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, 386 data, 387 adt7411_groups); 388 return PTR_ERR_OR_ZERO(hwmon_dev); 389 } 390 391 static const struct i2c_device_id adt7411_id[] = { 392 { "adt7411", 0 }, 393 { } 394 }; 395 MODULE_DEVICE_TABLE(i2c, adt7411_id); 396 397 static struct i2c_driver adt7411_driver = { 398 .driver = { 399 .name = "adt7411", 400 }, 401 .probe = adt7411_probe, 402 .id_table = adt7411_id, 403 .detect = adt7411_detect, 404 .address_list = normal_i2c, 405 .class = I2C_CLASS_HWMON, 406 }; 407 408 module_i2c_driver(adt7411_driver); 409 410 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and " 411 "Wolfram Sang <w.sang@pengutronix.de>"); 412 MODULE_DESCRIPTION("ADT7411 driver"); 413 MODULE_LICENSE("GPL v2"); 414