diff options
Diffstat (limited to 'drivers/hwmon/lm95245.c')
| -rw-r--r-- | drivers/hwmon/lm95245.c | 648 |
1 files changed, 648 insertions, 0 deletions
diff --git a/drivers/hwmon/lm95245.c b/drivers/hwmon/lm95245.c new file mode 100644 index 000000000..27cb06d65 --- /dev/null +++ b/drivers/hwmon/lm95245.c @@ -0,0 +1,648 @@ +/* + * Copyright (C) 2011 Alexander Stein <alexander.stein@systec-electronic.com> + * + * The LM95245 is a sensor chip made by TI / National Semiconductor. + * It reports up to two temperatures (its own plus an external one). + * + * This driver is based on lm95241.c + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/err.h> +#include <linux/init.h> +#include <linux/hwmon.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +static const unsigned short normal_i2c[] = { + 0x18, 0x19, 0x29, 0x4c, 0x4d, I2C_CLIENT_END }; + +/* LM95245 registers */ +/* general registers */ +#define LM95245_REG_RW_CONFIG1 0x03 +#define LM95245_REG_RW_CONVERS_RATE 0x04 +#define LM95245_REG_W_ONE_SHOT 0x0F + +/* diode configuration */ +#define LM95245_REG_RW_CONFIG2 0xBF +#define LM95245_REG_RW_REMOTE_OFFH 0x11 +#define LM95245_REG_RW_REMOTE_OFFL 0x12 + +/* status registers */ +#define LM95245_REG_R_STATUS1 0x02 +#define LM95245_REG_R_STATUS2 0x33 + +/* limit registers */ +#define LM95245_REG_RW_REMOTE_OS_LIMIT 0x07 +#define LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT 0x20 +#define LM95245_REG_RW_REMOTE_TCRIT_LIMIT 0x19 +#define LM95245_REG_RW_COMMON_HYSTERESIS 0x21 + +/* temperature signed */ +#define LM95245_REG_R_LOCAL_TEMPH_S 0x00 +#define LM95245_REG_R_LOCAL_TEMPL_S 0x30 +#define LM95245_REG_R_REMOTE_TEMPH_S 0x01 +#define LM95245_REG_R_REMOTE_TEMPL_S 0x10 +/* temperature unsigned */ +#define LM95245_REG_R_REMOTE_TEMPH_U 0x31 +#define LM95245_REG_R_REMOTE_TEMPL_U 0x32 + +/* id registers */ +#define LM95245_REG_R_MAN_ID 0xFE +#define LM95245_REG_R_CHIP_ID 0xFF + +/* LM95245 specific bitfields */ +#define CFG_STOP 0x40 +#define CFG_REMOTE_TCRIT_MASK 0x10 +#define CFG_REMOTE_OS_MASK 0x08 +#define CFG_LOCAL_TCRIT_MASK 0x04 +#define CFG_LOCAL_OS_MASK 0x02 + +#define CFG2_OS_A0 0x40 +#define CFG2_DIODE_FAULT_OS 0x20 +#define CFG2_DIODE_FAULT_TCRIT 0x10 +#define CFG2_REMOTE_TT 0x08 +#define CFG2_REMOTE_FILTER_DIS 0x00 +#define CFG2_REMOTE_FILTER_EN 0x06 + +/* conversation rate in ms */ +#define RATE_CR0063 0x00 +#define RATE_CR0364 0x01 +#define RATE_CR1000 0x02 +#define RATE_CR2500 0x03 + +#define STATUS1_ROS 0x10 +#define STATUS1_DIODE_FAULT 0x04 +#define STATUS1_RTCRIT 0x02 +#define STATUS1_LOC 0x01 + +#define MANUFACTURER_ID 0x01 +#define LM95235_REVISION 0xB1 +#define LM95245_REVISION 0xB3 + +static const u8 lm95245_reg_address[] = { + LM95245_REG_R_LOCAL_TEMPH_S, + LM95245_REG_R_LOCAL_TEMPL_S, + LM95245_REG_R_REMOTE_TEMPH_S, + LM95245_REG_R_REMOTE_TEMPL_S, + LM95245_REG_R_REMOTE_TEMPH_U, + LM95245_REG_R_REMOTE_TEMPL_U, + LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT, + LM95245_REG_RW_REMOTE_TCRIT_LIMIT, + LM95245_REG_RW_COMMON_HYSTERESIS, + LM95245_REG_R_STATUS1, +}; + +/* Client data (each client gets its own) */ +struct lm95245_data { + struct regmap *regmap; + struct mutex update_lock; + int interval; /* in msecs */ +}; + +/* Conversions */ +static int temp_from_reg_unsigned(u8 val_h, u8 val_l) +{ + return val_h * 1000 + val_l * 1000 / 256; +} + +static int temp_from_reg_signed(u8 val_h, u8 val_l) +{ + if (val_h & 0x80) + return (val_h - 0x100) * 1000; + return temp_from_reg_unsigned(val_h, val_l); +} + +static int lm95245_read_conversion_rate(struct lm95245_data *data) +{ + unsigned int rate; + int ret; + + ret = regmap_read(data->regmap, LM95245_REG_RW_CONVERS_RATE, &rate); + if (ret < 0) + return ret; + + switch (rate) { + case RATE_CR0063: + data->interval = 63; + break; + case RATE_CR0364: + data->interval = 364; + break; + case RATE_CR1000: + data->interval = 1000; + break; + case RATE_CR2500: + default: + data->interval = 2500; + break; + } + return 0; +} + +static int lm95245_set_conversion_rate(struct lm95245_data *data, long interval) +{ + int ret, rate; + + if (interval <= 63) { + interval = 63; + rate = RATE_CR0063; + } else if (interval <= 364) { + interval = 364; + rate = RATE_CR0364; + } else if (interval <= 1000) { + interval = 1000; + rate = RATE_CR1000; + } else { + interval = 2500; + rate = RATE_CR2500; + } + + ret = regmap_write(data->regmap, LM95245_REG_RW_CONVERS_RATE, rate); + if (ret < 0) + return ret; + + data->interval = interval; + return 0; +} + +static int lm95245_read_temp(struct device *dev, u32 attr, int channel, + long *val) +{ + struct lm95245_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + int ret, regl, regh, regvall, regvalh; + + switch (attr) { + case hwmon_temp_input: + regl = channel ? LM95245_REG_R_REMOTE_TEMPL_S : + LM95245_REG_R_LOCAL_TEMPL_S; + regh = channel ? LM95245_REG_R_REMOTE_TEMPH_S : + LM95245_REG_R_LOCAL_TEMPH_S; + ret = regmap_read(regmap, regl, ®vall); + if (ret < 0) + return ret; + ret = regmap_read(regmap, regh, ®valh); + if (ret < 0) + return ret; + /* + * Local temp is always signed. + * Remote temp has both signed and unsigned data. + * Use signed calculation for remote if signed bit is set + * or if reported temperature is below signed limit. + */ + if (!channel || (regvalh & 0x80) || regvalh < 0x7f) { + *val = temp_from_reg_signed(regvalh, regvall); + return 0; + } + ret = regmap_read(regmap, LM95245_REG_R_REMOTE_TEMPL_U, + ®vall); + if (ret < 0) + return ret; + ret = regmap_read(regmap, LM95245_REG_R_REMOTE_TEMPH_U, + ®valh); + if (ret < 0) + return ret; + *val = temp_from_reg_unsigned(regvalh, regvall); + return 0; + case hwmon_temp_max: + ret = regmap_read(regmap, LM95245_REG_RW_REMOTE_OS_LIMIT, + ®valh); + if (ret < 0) + return ret; + *val = regvalh * 1000; + return 0; + case hwmon_temp_crit: + regh = channel ? LM95245_REG_RW_REMOTE_TCRIT_LIMIT : + LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT; + ret = regmap_read(regmap, regh, ®valh); + if (ret < 0) + return ret; + *val = regvalh * 1000; + return 0; + case hwmon_temp_max_hyst: + ret = regmap_read(regmap, LM95245_REG_RW_REMOTE_OS_LIMIT, + ®valh); + if (ret < 0) + return ret; + ret = regmap_read(regmap, LM95245_REG_RW_COMMON_HYSTERESIS, + ®vall); + if (ret < 0) + return ret; + *val = (regvalh - regvall) * 1000; + return 0; + case hwmon_temp_crit_hyst: + regh = channel ? LM95245_REG_RW_REMOTE_TCRIT_LIMIT : + LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT; + ret = regmap_read(regmap, regh, ®valh); + if (ret < 0) + return ret; + ret = regmap_read(regmap, LM95245_REG_RW_COMMON_HYSTERESIS, + ®vall); + if (ret < 0) + return ret; + *val = (regvalh - regvall) * 1000; + return 0; + case hwmon_temp_type: + ret = regmap_read(regmap, LM95245_REG_RW_CONFIG2, ®valh); + if (ret < 0) + return ret; + *val = (regvalh & CFG2_REMOTE_TT) ? 1 : 2; + return 0; + case hwmon_temp_offset: + ret = regmap_read(regmap, LM95245_REG_RW_REMOTE_OFFL, + ®vall); + if (ret < 0) + return ret; + ret = regmap_read(regmap, LM95245_REG_RW_REMOTE_OFFH, + ®valh); + if (ret < 0) + return ret; + *val = temp_from_reg_signed(regvalh, regvall); + return 0; + case hwmon_temp_max_alarm: + ret = regmap_read(regmap, LM95245_REG_R_STATUS1, ®valh); + if (ret < 0) + return ret; + *val = !!(regvalh & STATUS1_ROS); + return 0; + case hwmon_temp_crit_alarm: + ret = regmap_read(regmap, LM95245_REG_R_STATUS1, ®valh); + if (ret < 0) + return ret; + *val = !!(regvalh & (channel ? STATUS1_RTCRIT : STATUS1_LOC)); + return 0; + case hwmon_temp_fault: + ret = regmap_read(regmap, LM95245_REG_R_STATUS1, ®valh); + if (ret < 0) + return ret; + *val = !!(regvalh & STATUS1_DIODE_FAULT); + return 0; + default: + return -EOPNOTSUPP; + } +} + +static int lm95245_write_temp(struct device *dev, u32 attr, int channel, + long val) +{ + struct lm95245_data *data = dev_get_drvdata(dev); + struct regmap *regmap = data->regmap; + unsigned int regval; + int ret, reg; + + switch (attr) { + case hwmon_temp_max: + val = clamp_val(val / 1000, 0, 255); + ret = regmap_write(regmap, LM95245_REG_RW_REMOTE_OS_LIMIT, val); + return ret; + case hwmon_temp_crit: + reg = channel ? LM95245_REG_RW_REMOTE_TCRIT_LIMIT : + LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT; + val = clamp_val(val / 1000, 0, channel ? 255 : 127); + ret = regmap_write(regmap, reg, val); + return ret; + case hwmon_temp_crit_hyst: + mutex_lock(&data->update_lock); + ret = regmap_read(regmap, LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT, + ®val); + if (ret < 0) { + mutex_unlock(&data->update_lock); + return ret; + } + /* Clamp to reasonable range to prevent overflow */ + val = clamp_val(val, -1000000, 1000000); + val = regval - val / 1000; + val = clamp_val(val, 0, 31); + ret = regmap_write(regmap, LM95245_REG_RW_COMMON_HYSTERESIS, + val); + mutex_unlock(&data->update_lock); + return ret; + case hwmon_temp_offset: + val = clamp_val(val, -128000, 127875); + val = val * 256 / 1000; + mutex_lock(&data->update_lock); + ret = regmap_write(regmap, LM95245_REG_RW_REMOTE_OFFL, + val & 0xe0); + if (ret < 0) { + mutex_unlock(&data->update_lock); + return ret; + } + ret = regmap_write(regmap, LM95245_REG_RW_REMOTE_OFFH, + (val >> 8) & 0xff); + mutex_unlock(&data->update_lock); + return ret; + case hwmon_temp_type: + if (val != 1 && val != 2) + return -EINVAL; + ret = regmap_update_bits(regmap, LM95245_REG_RW_CONFIG2, + CFG2_REMOTE_TT, + val == 1 ? CFG2_REMOTE_TT : 0); + return ret; + default: + return -EOPNOTSUPP; + } +} + +static int lm95245_read_chip(struct device *dev, u32 attr, int channel, + long *val) +{ + struct lm95245_data *data = dev_get_drvdata(dev); + + switch (attr) { + case hwmon_chip_update_interval: + *val = data->interval; + return 0; + default: + return -EOPNOTSUPP; + } +} + +static int lm95245_write_chip(struct device *dev, u32 attr, int channel, + long val) +{ + struct lm95245_data *data = dev_get_drvdata(dev); + int ret; + + switch (attr) { + case hwmon_chip_update_interval: + mutex_lock(&data->update_lock); + ret = lm95245_set_conversion_rate(data, val); + mutex_unlock(&data->update_lock); + return ret; + default: + return -EOPNOTSUPP; + } +} + +static int lm95245_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + switch (type) { + case hwmon_chip: + return lm95245_read_chip(dev, attr, channel, val); + case hwmon_temp: + return lm95245_read_temp(dev, attr, channel, val); + default: + return -EOPNOTSUPP; + } +} + +static int lm95245_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long val) +{ + switch (type) { + case hwmon_chip: + return lm95245_write_chip(dev, attr, channel, val); + case hwmon_temp: + return lm95245_write_temp(dev, attr, channel, val); + default: + return -EOPNOTSUPP; + } +} + +static umode_t lm95245_temp_is_visible(const void *data, u32 attr, int channel) +{ + switch (attr) { + case hwmon_temp_input: + case hwmon_temp_max_alarm: + case hwmon_temp_max_hyst: + case hwmon_temp_crit_alarm: + case hwmon_temp_fault: + return S_IRUGO; + case hwmon_temp_type: + case hwmon_temp_max: + case hwmon_temp_crit: + case hwmon_temp_offset: + return S_IRUGO | S_IWUSR; + case hwmon_temp_crit_hyst: + return (channel == 0) ? S_IRUGO | S_IWUSR : S_IRUGO; + default: + return 0; + } +} + +static umode_t lm95245_is_visible(const void *data, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + switch (type) { + case hwmon_chip: + switch (attr) { + case hwmon_chip_update_interval: + return S_IRUGO | S_IWUSR; + default: + return 0; + } + case hwmon_temp: + return lm95245_temp_is_visible(data, attr, channel); + default: + return 0; + } +} + +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int lm95245_detect(struct i2c_client *new_client, + struct i2c_board_info *info) +{ + struct i2c_adapter *adapter = new_client->adapter; + int address = new_client->addr; + const char *name; + int rev, id; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) + return -ENODEV; + + id = i2c_smbus_read_byte_data(new_client, LM95245_REG_R_MAN_ID); + if (id != MANUFACTURER_ID) + return -ENODEV; + + rev = i2c_smbus_read_byte_data(new_client, LM95245_REG_R_CHIP_ID); + switch (rev) { + case LM95235_REVISION: + if (address != 0x18 && address != 0x29 && address != 0x4c) + return -ENODEV; + name = "lm95235"; + break; + case LM95245_REVISION: + name = "lm95245"; + break; + default: + return -ENODEV; + } + + strlcpy(info->type, name, I2C_NAME_SIZE); + return 0; +} + +static int lm95245_init_client(struct lm95245_data *data) +{ + int ret; + + ret = lm95245_read_conversion_rate(data); + if (ret < 0) + return ret; + + return regmap_update_bits(data->regmap, LM95245_REG_RW_CONFIG1, + CFG_STOP, 0); +} + +static bool lm95245_is_writeable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LM95245_REG_RW_CONFIG1: + case LM95245_REG_RW_CONVERS_RATE: + case LM95245_REG_W_ONE_SHOT: + case LM95245_REG_RW_CONFIG2: + case LM95245_REG_RW_REMOTE_OFFH: + case LM95245_REG_RW_REMOTE_OFFL: + case LM95245_REG_RW_REMOTE_OS_LIMIT: + case LM95245_REG_RW_LOCAL_OS_TCRIT_LIMIT: + case LM95245_REG_RW_REMOTE_TCRIT_LIMIT: + case LM95245_REG_RW_COMMON_HYSTERESIS: + return true; + default: + return false; + } +} + +static bool lm95245_is_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LM95245_REG_R_STATUS1: + case LM95245_REG_R_STATUS2: + case LM95245_REG_R_LOCAL_TEMPH_S: + case LM95245_REG_R_LOCAL_TEMPL_S: + case LM95245_REG_R_REMOTE_TEMPH_S: + case LM95245_REG_R_REMOTE_TEMPL_S: + case LM95245_REG_R_REMOTE_TEMPH_U: + case LM95245_REG_R_REMOTE_TEMPL_U: + return true; + default: + return false; + } +} + +static const struct regmap_config lm95245_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .writeable_reg = lm95245_is_writeable_reg, + .volatile_reg = lm95245_is_volatile_reg, + .cache_type = REGCACHE_RBTREE, + .use_single_rw = true, +}; + +static const u32 lm95245_chip_config[] = { + HWMON_C_UPDATE_INTERVAL, + 0 +}; + +static const struct hwmon_channel_info lm95245_chip = { + .type = hwmon_chip, + .config = lm95245_chip_config, +}; + +static const u32 lm95245_temp_config[] = { + HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_HYST | HWMON_T_CRIT_ALARM, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST | HWMON_T_CRIT | + HWMON_T_CRIT_HYST | HWMON_T_FAULT | HWMON_T_MAX_ALARM | + HWMON_T_CRIT_ALARM | HWMON_T_TYPE | HWMON_T_OFFSET, + 0 +}; + +static const struct hwmon_channel_info lm95245_temp = { + .type = hwmon_temp, + .config = lm95245_temp_config, +}; + +static const struct hwmon_channel_info *lm95245_info[] = { + &lm95245_chip, + &lm95245_temp, + NULL +}; + +static const struct hwmon_ops lm95245_hwmon_ops = { + .is_visible = lm95245_is_visible, + .read = lm95245_read, + .write = lm95245_write, +}; + +static const struct hwmon_chip_info lm95245_chip_info = { + .ops = &lm95245_hwmon_ops, + .info = lm95245_info, +}; + +static int lm95245_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct lm95245_data *data; + struct device *hwmon_dev; + int ret; + + data = devm_kzalloc(dev, sizeof(struct lm95245_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->regmap = devm_regmap_init_i2c(client, &lm95245_regmap_config); + if (IS_ERR(data->regmap)) + return PTR_ERR(data->regmap); + + mutex_init(&data->update_lock); + + /* Initialize the LM95245 chip */ + ret = lm95245_init_client(data); + if (ret < 0) + return ret; + + hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, + data, + &lm95245_chip_info, + NULL); + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +/* Driver data (common to all clients) */ +static const struct i2c_device_id lm95245_id[] = { + { "lm95235", 0 }, + { "lm95245", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, lm95245_id); + +static const struct of_device_id lm95245_of_match[] = { + { .compatible = "national,lm95235" }, + { .compatible = "national,lm95245" }, + { }, +}; +MODULE_DEVICE_TABLE(of, lm95245_of_match); + +static struct i2c_driver lm95245_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "lm95245", + .of_match_table = of_match_ptr(lm95245_of_match), + }, + .probe = lm95245_probe, + .id_table = lm95245_id, + .detect = lm95245_detect, + .address_list = normal_i2c, +}; + +module_i2c_driver(lm95245_driver); + +MODULE_AUTHOR("Alexander Stein <alexander.stein@systec-electronic.com>"); +MODULE_DESCRIPTION("LM95235/LM95245 sensor driver"); +MODULE_LICENSE("GPL"); |