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 i2c_client *client; 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 struct ad7418_data *ad7418_update_device(struct device *dev) 58 { 59 struct ad7418_data *data = dev_get_drvdata(dev); 60 struct i2c_client *client = data->client; 61 62 mutex_lock(&data->lock); 63 64 if (time_after(jiffies, data->last_updated + HZ + HZ / 2) 65 || !data->valid) { 66 u8 cfg; 67 int i, ch; 68 69 /* read config register and clear channel bits */ 70 cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 71 cfg &= 0x1F; 72 73 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, 74 cfg | AD7418_CH_TEMP); 75 udelay(30); 76 77 for (i = 0; i < 3; i++) { 78 data->temp[i] = 79 i2c_smbus_read_word_swapped(client, 80 AD7418_REG_TEMP[i]); 81 } 82 83 for (i = 0, ch = 4; i < data->adc_max; i++, ch--) { 84 i2c_smbus_write_byte_data(client, 85 AD7418_REG_CONF, 86 cfg | AD7418_REG_ADC_CH(ch)); 87 88 udelay(15); 89 data->in[data->adc_max - 1 - i] = 90 i2c_smbus_read_word_swapped(client, 91 AD7418_REG_ADC); 92 } 93 94 /* restore old configuration value */ 95 i2c_smbus_write_word_swapped(client, AD7418_REG_CONF, cfg); 96 97 data->last_updated = jiffies; 98 data->valid = 1; 99 } 100 101 mutex_unlock(&data->lock); 102 103 return data; 104 } 105 106 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 107 char *buf) 108 { 109 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 110 struct ad7418_data *data = ad7418_update_device(dev); 111 return sprintf(buf, "%d\n", 112 LM75_TEMP_FROM_REG(data->temp[attr->index])); 113 } 114 115 static ssize_t show_adc(struct device *dev, struct device_attribute *devattr, 116 char *buf) 117 { 118 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 119 struct ad7418_data *data = ad7418_update_device(dev); 120 121 return sprintf(buf, "%d\n", 122 ((data->in[attr->index] >> 6) * 2500 + 512) / 1024); 123 } 124 125 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr, 126 const char *buf, size_t count) 127 { 128 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 129 struct ad7418_data *data = dev_get_drvdata(dev); 130 struct i2c_client *client = data->client; 131 long temp; 132 int ret = kstrtol(buf, 10, &temp); 133 134 if (ret < 0) 135 return ret; 136 137 mutex_lock(&data->lock); 138 data->temp[attr->index] = LM75_TEMP_TO_REG(temp); 139 i2c_smbus_write_word_swapped(client, 140 AD7418_REG_TEMP[attr->index], 141 data->temp[attr->index]); 142 mutex_unlock(&data->lock); 143 return count; 144 } 145 146 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); 147 static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, 148 show_temp, set_temp, 1); 149 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, 150 show_temp, set_temp, 2); 151 152 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, show_adc, NULL, 0); 153 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, show_adc, NULL, 1); 154 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, show_adc, NULL, 2); 155 static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, show_adc, NULL, 3); 156 157 static struct attribute *ad7416_attrs[] = { 158 &sensor_dev_attr_temp1_max.dev_attr.attr, 159 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 160 &sensor_dev_attr_temp1_input.dev_attr.attr, 161 NULL 162 }; 163 ATTRIBUTE_GROUPS(ad7416); 164 165 static struct attribute *ad7417_attrs[] = { 166 &sensor_dev_attr_temp1_max.dev_attr.attr, 167 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 168 &sensor_dev_attr_temp1_input.dev_attr.attr, 169 &sensor_dev_attr_in1_input.dev_attr.attr, 170 &sensor_dev_attr_in2_input.dev_attr.attr, 171 &sensor_dev_attr_in3_input.dev_attr.attr, 172 &sensor_dev_attr_in4_input.dev_attr.attr, 173 NULL 174 }; 175 ATTRIBUTE_GROUPS(ad7417); 176 177 static struct attribute *ad7418_attrs[] = { 178 &sensor_dev_attr_temp1_max.dev_attr.attr, 179 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, 180 &sensor_dev_attr_temp1_input.dev_attr.attr, 181 &sensor_dev_attr_in1_input.dev_attr.attr, 182 NULL 183 }; 184 ATTRIBUTE_GROUPS(ad7418); 185 186 static void ad7418_init_client(struct i2c_client *client) 187 { 188 struct ad7418_data *data = i2c_get_clientdata(client); 189 190 int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF); 191 if (reg < 0) { 192 dev_err(&client->dev, "cannot read configuration register\n"); 193 } else { 194 dev_info(&client->dev, "configuring for mode 1\n"); 195 i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe); 196 197 if (data->type == ad7417 || data->type == ad7418) 198 i2c_smbus_write_byte_data(client, 199 AD7418_REG_CONF2, 0x00); 200 } 201 } 202 203 static int ad7418_probe(struct i2c_client *client, 204 const struct i2c_device_id *id) 205 { 206 struct device *dev = &client->dev; 207 struct i2c_adapter *adapter = client->adapter; 208 struct ad7418_data *data; 209 struct device *hwmon_dev; 210 const struct attribute_group **attr_groups = NULL; 211 212 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | 213 I2C_FUNC_SMBUS_WORD_DATA)) 214 return -EOPNOTSUPP; 215 216 data = devm_kzalloc(dev, sizeof(struct ad7418_data), GFP_KERNEL); 217 if (!data) 218 return -ENOMEM; 219 220 i2c_set_clientdata(client, data); 221 222 mutex_init(&data->lock); 223 data->client = client; 224 data->type = id->driver_data; 225 226 switch (data->type) { 227 case ad7416: 228 data->adc_max = 0; 229 attr_groups = ad7416_groups; 230 break; 231 232 case ad7417: 233 data->adc_max = 4; 234 attr_groups = ad7417_groups; 235 break; 236 237 case ad7418: 238 data->adc_max = 1; 239 attr_groups = ad7418_groups; 240 break; 241 } 242 243 dev_info(dev, "%s chip found\n", client->name); 244 245 /* Initialize the AD7418 chip */ 246 ad7418_init_client(client); 247 248 hwmon_dev = devm_hwmon_device_register_with_groups(dev, 249 client->name, 250 data, attr_groups); 251 return PTR_ERR_OR_ZERO(hwmon_dev); 252 } 253 254 static const struct i2c_device_id ad7418_id[] = { 255 { "ad7416", ad7416 }, 256 { "ad7417", ad7417 }, 257 { "ad7418", ad7418 }, 258 { } 259 }; 260 MODULE_DEVICE_TABLE(i2c, ad7418_id); 261 262 static struct i2c_driver ad7418_driver = { 263 .driver = { 264 .name = "ad7418", 265 }, 266 .probe = ad7418_probe, 267 .id_table = ad7418_id, 268 }; 269 270 module_i2c_driver(ad7418_driver); 271 272 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); 273 MODULE_DESCRIPTION("AD7416/17/18 driver"); 274 MODULE_LICENSE("GPL"); 275 MODULE_VERSION(DRV_VERSION); 276