1ee249f27SLei YU /* 2ee249f27SLei YU * Copyright (C) 2017 IBM Corp. 3ee249f27SLei YU * 4ee249f27SLei YU * This program is free software; you can redistribute it and/or modify 5ee249f27SLei YU * it under the terms of the GNU General Public License as published by 6ee249f27SLei YU * the Free Software Foundation; either version 2 of the License, or 7ee249f27SLei YU * (at your option) any later version. 8ee249f27SLei YU * 9ee249f27SLei YU * Driver for the Nuvoton W83773G SMBus temperature sensor IC. 10ee249f27SLei YU * Supported models: W83773G 11ee249f27SLei YU */ 12ee249f27SLei YU 13ee249f27SLei YU #include <linux/module.h> 14ee249f27SLei YU #include <linux/init.h> 15ee249f27SLei YU #include <linux/i2c.h> 16ee249f27SLei YU #include <linux/hwmon.h> 17ee249f27SLei YU #include <linux/hwmon-sysfs.h> 18ee249f27SLei YU #include <linux/err.h> 19ee249f27SLei YU #include <linux/of_device.h> 20ee249f27SLei YU #include <linux/regmap.h> 21ee249f27SLei YU 22ee249f27SLei YU /* W83773 has 3 channels */ 23ee249f27SLei YU #define W83773_CHANNELS 3 24ee249f27SLei YU 25ee249f27SLei YU /* The W83773 registers */ 26ee249f27SLei YU #define W83773_CONVERSION_RATE_REG_READ 0x04 27ee249f27SLei YU #define W83773_CONVERSION_RATE_REG_WRITE 0x0A 28ee249f27SLei YU #define W83773_MANUFACTURER_ID_REG 0xFE 29ee249f27SLei YU #define W83773_LOCAL_TEMP 0x00 30ee249f27SLei YU 31ee249f27SLei YU static const u8 W83773_STATUS[2] = { 0x02, 0x17 }; 32ee249f27SLei YU 33ee249f27SLei YU static const u8 W83773_TEMP_LSB[2] = { 0x10, 0x25 }; 34ee249f27SLei YU static const u8 W83773_TEMP_MSB[2] = { 0x01, 0x24 }; 35ee249f27SLei YU 36ee249f27SLei YU static const u8 W83773_OFFSET_LSB[2] = { 0x12, 0x16 }; 37ee249f27SLei YU static const u8 W83773_OFFSET_MSB[2] = { 0x11, 0x15 }; 38ee249f27SLei YU 39ee249f27SLei YU /* this is the number of sensors in the device */ 40ee249f27SLei YU static const struct i2c_device_id w83773_id[] = { 41ee249f27SLei YU { "w83773g" }, 42ee249f27SLei YU { } 43ee249f27SLei YU }; 44ee249f27SLei YU 45ee249f27SLei YU MODULE_DEVICE_TABLE(i2c, w83773_id); 46ee249f27SLei YU 47ee249f27SLei YU static const struct of_device_id w83773_of_match[] = { 48ee249f27SLei YU { 49ee249f27SLei YU .compatible = "nuvoton,w83773g" 50ee249f27SLei YU }, 51ee249f27SLei YU { }, 52ee249f27SLei YU }; 53ee249f27SLei YU MODULE_DEVICE_TABLE(of, w83773_of_match); 54ee249f27SLei YU 55ee249f27SLei YU static inline long temp_of_local(s8 reg) 56ee249f27SLei YU { 57ee249f27SLei YU return reg * 1000; 58ee249f27SLei YU } 59ee249f27SLei YU 60ee249f27SLei YU static inline long temp_of_remote(s8 hb, u8 lb) 61ee249f27SLei YU { 62ee249f27SLei YU return (hb << 3 | lb >> 5) * 125; 63ee249f27SLei YU } 64ee249f27SLei YU 65ee249f27SLei YU static int get_local_temp(struct regmap *regmap, long *val) 66ee249f27SLei YU { 67ee249f27SLei YU unsigned int regval; 68ee249f27SLei YU int ret; 69ee249f27SLei YU 70ee249f27SLei YU ret = regmap_read(regmap, W83773_LOCAL_TEMP, ®val); 71ee249f27SLei YU if (ret < 0) 72ee249f27SLei YU return ret; 73ee249f27SLei YU 74ee249f27SLei YU *val = temp_of_local(regval); 75ee249f27SLei YU return 0; 76ee249f27SLei YU } 77ee249f27SLei YU 78ee249f27SLei YU static int get_remote_temp(struct regmap *regmap, int index, long *val) 79ee249f27SLei YU { 80ee249f27SLei YU unsigned int regval_high; 81ee249f27SLei YU unsigned int regval_low; 82ee249f27SLei YU int ret; 83ee249f27SLei YU 84ee249f27SLei YU ret = regmap_read(regmap, W83773_TEMP_MSB[index], ®val_high); 85ee249f27SLei YU if (ret < 0) 86ee249f27SLei YU return ret; 87ee249f27SLei YU 88ee249f27SLei YU ret = regmap_read(regmap, W83773_TEMP_LSB[index], ®val_low); 89ee249f27SLei YU if (ret < 0) 90ee249f27SLei YU return ret; 91ee249f27SLei YU 92ee249f27SLei YU *val = temp_of_remote(regval_high, regval_low); 93ee249f27SLei YU return 0; 94ee249f27SLei YU } 95ee249f27SLei YU 96ee249f27SLei YU static int get_fault(struct regmap *regmap, int index, long *val) 97ee249f27SLei YU { 98ee249f27SLei YU unsigned int regval; 99ee249f27SLei YU int ret; 100ee249f27SLei YU 101ee249f27SLei YU ret = regmap_read(regmap, W83773_STATUS[index], ®val); 102ee249f27SLei YU if (ret < 0) 103ee249f27SLei YU return ret; 104ee249f27SLei YU 105571e3f3aSGuenter Roeck *val = (regval & 0x04) >> 2; 106ee249f27SLei YU return 0; 107ee249f27SLei YU } 108ee249f27SLei YU 109ee249f27SLei YU static int get_offset(struct regmap *regmap, int index, long *val) 110ee249f27SLei YU { 111ee249f27SLei YU unsigned int regval_high; 112ee249f27SLei YU unsigned int regval_low; 113ee249f27SLei YU int ret; 114ee249f27SLei YU 115ee249f27SLei YU ret = regmap_read(regmap, W83773_OFFSET_MSB[index], ®val_high); 116ee249f27SLei YU if (ret < 0) 117ee249f27SLei YU return ret; 118ee249f27SLei YU 119ee249f27SLei YU ret = regmap_read(regmap, W83773_OFFSET_LSB[index], ®val_low); 120ee249f27SLei YU if (ret < 0) 121ee249f27SLei YU return ret; 122ee249f27SLei YU 123ee249f27SLei YU *val = temp_of_remote(regval_high, regval_low); 124ee249f27SLei YU return 0; 125ee249f27SLei YU } 126ee249f27SLei YU 127ee249f27SLei YU static int set_offset(struct regmap *regmap, int index, long val) 128ee249f27SLei YU { 129ee249f27SLei YU int ret; 130ee249f27SLei YU u8 high_byte; 131ee249f27SLei YU u8 low_byte; 132ee249f27SLei YU 133ee249f27SLei YU val = clamp_val(val, -127825, 127825); 134ee249f27SLei YU /* offset value equals to (high_byte << 3 | low_byte >> 5) * 125 */ 135ee249f27SLei YU val /= 125; 136ee249f27SLei YU high_byte = val >> 3; 137ee249f27SLei YU low_byte = (val & 0x07) << 5; 138ee249f27SLei YU 139ee249f27SLei YU ret = regmap_write(regmap, W83773_OFFSET_MSB[index], high_byte); 140ee249f27SLei YU if (ret < 0) 141ee249f27SLei YU return ret; 142ee249f27SLei YU 143ee249f27SLei YU return regmap_write(regmap, W83773_OFFSET_LSB[index], low_byte); 144ee249f27SLei YU } 145ee249f27SLei YU 146ee249f27SLei YU static int get_update_interval(struct regmap *regmap, long *val) 147ee249f27SLei YU { 148ee249f27SLei YU unsigned int regval; 149ee249f27SLei YU int ret; 150ee249f27SLei YU 151ee249f27SLei YU ret = regmap_read(regmap, W83773_CONVERSION_RATE_REG_READ, ®val); 152ee249f27SLei YU if (ret < 0) 153ee249f27SLei YU return ret; 154ee249f27SLei YU 155ee249f27SLei YU *val = 16000 >> regval; 156ee249f27SLei YU return 0; 157ee249f27SLei YU } 158ee249f27SLei YU 159ee249f27SLei YU static int set_update_interval(struct regmap *regmap, long val) 160ee249f27SLei YU { 161ee249f27SLei YU int rate; 162ee249f27SLei YU 163ee249f27SLei YU /* 164ee249f27SLei YU * For valid rates, interval can be calculated as 165ee249f27SLei YU * interval = (1 << (8 - rate)) * 62.5; 166ee249f27SLei YU * Rounded rate is therefore 167ee249f27SLei YU * rate = 8 - __fls(interval * 8 / (62.5 * 7)); 168ee249f27SLei YU * Use clamp_val() to avoid overflows, and to ensure valid input 169ee249f27SLei YU * for __fls. 170ee249f27SLei YU */ 171ee249f27SLei YU val = clamp_val(val, 62, 16000) * 10; 172ee249f27SLei YU rate = 8 - __fls((val * 8 / (625 * 7))); 173ee249f27SLei YU return regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, rate); 174ee249f27SLei YU } 175ee249f27SLei YU 176ee249f27SLei YU static int w83773_read(struct device *dev, enum hwmon_sensor_types type, 177ee249f27SLei YU u32 attr, int channel, long *val) 178ee249f27SLei YU { 179ee249f27SLei YU struct regmap *regmap = dev_get_drvdata(dev); 180ee249f27SLei YU 181ee249f27SLei YU if (type == hwmon_chip) { 182ee249f27SLei YU if (attr == hwmon_chip_update_interval) 183ee249f27SLei YU return get_update_interval(regmap, val); 184ee249f27SLei YU return -EOPNOTSUPP; 185ee249f27SLei YU } 186ee249f27SLei YU 187ee249f27SLei YU switch (attr) { 188ee249f27SLei YU case hwmon_temp_input: 189ee249f27SLei YU if (channel == 0) 190ee249f27SLei YU return get_local_temp(regmap, val); 191ee249f27SLei YU return get_remote_temp(regmap, channel - 1, val); 192ee249f27SLei YU case hwmon_temp_fault: 193ee249f27SLei YU return get_fault(regmap, channel - 1, val); 194ee249f27SLei YU case hwmon_temp_offset: 195ee249f27SLei YU return get_offset(regmap, channel - 1, val); 196ee249f27SLei YU default: 197ee249f27SLei YU return -EOPNOTSUPP; 198ee249f27SLei YU } 199ee249f27SLei YU } 200ee249f27SLei YU 201ee249f27SLei YU static int w83773_write(struct device *dev, enum hwmon_sensor_types type, 202ee249f27SLei YU u32 attr, int channel, long val) 203ee249f27SLei YU { 204ee249f27SLei YU struct regmap *regmap = dev_get_drvdata(dev); 205ee249f27SLei YU 206ee249f27SLei YU if (type == hwmon_chip && attr == hwmon_chip_update_interval) 207ee249f27SLei YU return set_update_interval(regmap, val); 208ee249f27SLei YU 209ee249f27SLei YU if (type == hwmon_temp && attr == hwmon_temp_offset) 210ee249f27SLei YU return set_offset(regmap, channel - 1, val); 211ee249f27SLei YU 212ee249f27SLei YU return -EOPNOTSUPP; 213ee249f27SLei YU } 214ee249f27SLei YU 215ee249f27SLei YU static umode_t w83773_is_visible(const void *data, enum hwmon_sensor_types type, 216ee249f27SLei YU u32 attr, int channel) 217ee249f27SLei YU { 218ee249f27SLei YU switch (type) { 219ee249f27SLei YU case hwmon_chip: 220ee249f27SLei YU switch (attr) { 221ee249f27SLei YU case hwmon_chip_update_interval: 222ee249f27SLei YU return 0644; 223ee249f27SLei YU } 224ee249f27SLei YU break; 225ee249f27SLei YU case hwmon_temp: 226ee249f27SLei YU switch (attr) { 227ee249f27SLei YU case hwmon_temp_input: 228ee249f27SLei YU case hwmon_temp_fault: 229ee249f27SLei YU return 0444; 230ee249f27SLei YU case hwmon_temp_offset: 231ee249f27SLei YU return 0644; 232ee249f27SLei YU } 233ee249f27SLei YU break; 234ee249f27SLei YU default: 235ee249f27SLei YU break; 236ee249f27SLei YU } 237ee249f27SLei YU return 0; 238ee249f27SLei YU } 239ee249f27SLei YU 240*2f2defdaSGuenter Roeck static const struct hwmon_channel_info *w83773_info[] = { 241*2f2defdaSGuenter Roeck HWMON_CHANNEL_INFO(chip, 242*2f2defdaSGuenter Roeck HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL), 243*2f2defdaSGuenter Roeck HWMON_CHANNEL_INFO(temp, 244ee249f27SLei YU HWMON_T_INPUT, 245ee249f27SLei YU HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_OFFSET, 246*2f2defdaSGuenter Roeck HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_OFFSET), 247ee249f27SLei YU NULL 248ee249f27SLei YU }; 249ee249f27SLei YU 250ee249f27SLei YU static const struct hwmon_ops w83773_ops = { 251ee249f27SLei YU .is_visible = w83773_is_visible, 252ee249f27SLei YU .read = w83773_read, 253ee249f27SLei YU .write = w83773_write, 254ee249f27SLei YU }; 255ee249f27SLei YU 256ee249f27SLei YU static const struct hwmon_chip_info w83773_chip_info = { 257ee249f27SLei YU .ops = &w83773_ops, 258ee249f27SLei YU .info = w83773_info, 259ee249f27SLei YU }; 260ee249f27SLei YU 261ee249f27SLei YU static const struct regmap_config w83773_regmap_config = { 262ee249f27SLei YU .reg_bits = 8, 263ee249f27SLei YU .val_bits = 8, 264ee249f27SLei YU }; 265ee249f27SLei YU 266ee249f27SLei YU static int w83773_probe(struct i2c_client *client, 267ee249f27SLei YU const struct i2c_device_id *id) 268ee249f27SLei YU { 269ee249f27SLei YU struct device *dev = &client->dev; 270ee249f27SLei YU struct device *hwmon_dev; 271ee249f27SLei YU struct regmap *regmap; 272ee249f27SLei YU int ret; 273ee249f27SLei YU 274ee249f27SLei YU regmap = devm_regmap_init_i2c(client, &w83773_regmap_config); 275ee249f27SLei YU if (IS_ERR(regmap)) { 276ee249f27SLei YU dev_err(dev, "failed to allocate register map\n"); 277ee249f27SLei YU return PTR_ERR(regmap); 278ee249f27SLei YU } 279ee249f27SLei YU 280ee249f27SLei YU /* Set the conversion rate to 2 Hz */ 281ee249f27SLei YU ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, 0x05); 282ee249f27SLei YU if (ret < 0) { 283ee249f27SLei YU dev_err(&client->dev, "error writing config rate register\n"); 284ee249f27SLei YU return ret; 285ee249f27SLei YU } 286ee249f27SLei YU 287ee249f27SLei YU i2c_set_clientdata(client, regmap); 288ee249f27SLei YU 289ee249f27SLei YU hwmon_dev = devm_hwmon_device_register_with_info(dev, 290ee249f27SLei YU client->name, 291ee249f27SLei YU regmap, 292ee249f27SLei YU &w83773_chip_info, 293ee249f27SLei YU NULL); 294ee249f27SLei YU return PTR_ERR_OR_ZERO(hwmon_dev); 295ee249f27SLei YU } 296ee249f27SLei YU 297ee249f27SLei YU static struct i2c_driver w83773_driver = { 298ee249f27SLei YU .class = I2C_CLASS_HWMON, 299ee249f27SLei YU .driver = { 300ee249f27SLei YU .name = "w83773g", 301ee249f27SLei YU .of_match_table = of_match_ptr(w83773_of_match), 302ee249f27SLei YU }, 303ee249f27SLei YU .probe = w83773_probe, 304ee249f27SLei YU .id_table = w83773_id, 305ee249f27SLei YU }; 306ee249f27SLei YU 307ee249f27SLei YU module_i2c_driver(w83773_driver); 308ee249f27SLei YU 309ee249f27SLei YU MODULE_AUTHOR("Lei YU <mine260309@gmail.com>"); 310ee249f27SLei YU MODULE_DESCRIPTION("W83773G temperature sensor driver"); 311ee249f27SLei YU MODULE_LICENSE("GPL"); 312