diff options
Diffstat (limited to 'drivers/hwmon/lm95241.c')
| -rw-r--r-- | drivers/hwmon/lm95241.c | 481 |
1 files changed, 481 insertions, 0 deletions
diff --git a/drivers/hwmon/lm95241.c b/drivers/hwmon/lm95241.c new file mode 100644 index 000000000..f1ed777a8 --- /dev/null +++ b/drivers/hwmon/lm95241.c @@ -0,0 +1,481 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2008, 2010 Davide Rizzo <elpa.rizzo@gmail.com> + * + * The LM95241 is a sensor chip made by National Semiconductors. + * It reports up to three temperatures (its own plus up to two external ones). + * Complete datasheet can be obtained from National's website at: + * http://www.national.com/ds.cgi/LM/LM95241.pdf + */ + +#include <linux/bitops.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/jiffies.h> +#include <linux/hwmon.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> + +#define DEVNAME "lm95241" + +static const unsigned short normal_i2c[] = { + 0x19, 0x2a, 0x2b, I2C_CLIENT_END }; + +/* LM95241 registers */ +#define LM95241_REG_R_MAN_ID 0xFE +#define LM95241_REG_R_CHIP_ID 0xFF +#define LM95241_REG_R_STATUS 0x02 +#define LM95241_REG_RW_CONFIG 0x03 +#define LM95241_REG_RW_REM_FILTER 0x06 +#define LM95241_REG_RW_TRUTHERM 0x07 +#define LM95241_REG_W_ONE_SHOT 0x0F +#define LM95241_REG_R_LOCAL_TEMPH 0x10 +#define LM95241_REG_R_REMOTE1_TEMPH 0x11 +#define LM95241_REG_R_REMOTE2_TEMPH 0x12 +#define LM95241_REG_R_LOCAL_TEMPL 0x20 +#define LM95241_REG_R_REMOTE1_TEMPL 0x21 +#define LM95241_REG_R_REMOTE2_TEMPL 0x22 +#define LM95241_REG_RW_REMOTE_MODEL 0x30 + +/* LM95241 specific bitfields */ +#define CFG_STOP BIT(6) +#define CFG_CR0076 0x00 +#define CFG_CR0182 BIT(4) +#define CFG_CR1000 BIT(5) +#define CFG_CR2700 (BIT(4) | BIT(5)) +#define CFG_CRMASK (BIT(4) | BIT(5)) +#define R1MS_MASK BIT(0) +#define R2MS_MASK BIT(2) +#define R1DF_MASK BIT(1) +#define R2DF_MASK BIT(2) +#define R1FE_MASK BIT(0) +#define R2FE_MASK BIT(2) +#define R1DM BIT(0) +#define R2DM BIT(1) +#define TT1_SHIFT 0 +#define TT2_SHIFT 4 +#define TT_OFF 0 +#define TT_ON 1 +#define TT_MASK 7 +#define NATSEMI_MAN_ID 0x01 +#define LM95231_CHIP_ID 0xA1 +#define LM95241_CHIP_ID 0xA4 + +static const u8 lm95241_reg_address[] = { + LM95241_REG_R_LOCAL_TEMPH, + LM95241_REG_R_LOCAL_TEMPL, + LM95241_REG_R_REMOTE1_TEMPH, + LM95241_REG_R_REMOTE1_TEMPL, + LM95241_REG_R_REMOTE2_TEMPH, + LM95241_REG_R_REMOTE2_TEMPL +}; + +/* Client data (each client gets its own) */ +struct lm95241_data { + struct i2c_client *client; + struct mutex update_lock; + unsigned long last_updated; /* in jiffies */ + unsigned long interval; /* in milli-seconds */ + bool valid; /* false until following fields are valid */ + /* registers values */ + u8 temp[ARRAY_SIZE(lm95241_reg_address)]; + u8 status, config, model, trutherm; +}; + +/* Conversions */ +static int temp_from_reg_signed(u8 val_h, u8 val_l) +{ + s16 val_hl = (val_h << 8) | val_l; + return val_hl * 1000 / 256; +} + +static int temp_from_reg_unsigned(u8 val_h, u8 val_l) +{ + u16 val_hl = (val_h << 8) | val_l; + return val_hl * 1000 / 256; +} + +static struct lm95241_data *lm95241_update_device(struct device *dev) +{ + struct lm95241_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + + mutex_lock(&data->update_lock); + + if (time_after(jiffies, data->last_updated + + msecs_to_jiffies(data->interval)) || + !data->valid) { + int i; + + dev_dbg(dev, "Updating lm95241 data.\n"); + for (i = 0; i < ARRAY_SIZE(lm95241_reg_address); i++) + data->temp[i] + = i2c_smbus_read_byte_data(client, + lm95241_reg_address[i]); + + data->status = i2c_smbus_read_byte_data(client, + LM95241_REG_R_STATUS); + data->last_updated = jiffies; + data->valid = true; + } + + mutex_unlock(&data->update_lock); + + return data; +} + +static int lm95241_read_chip(struct device *dev, u32 attr, int channel, + long *val) +{ + struct lm95241_data *data = dev_get_drvdata(dev); + + switch (attr) { + case hwmon_chip_update_interval: + *val = data->interval; + return 0; + default: + return -EOPNOTSUPP; + } +} + +static int lm95241_read_temp(struct device *dev, u32 attr, int channel, + long *val) +{ + struct lm95241_data *data = lm95241_update_device(dev); + + switch (attr) { + case hwmon_temp_input: + if (!channel || (data->config & BIT(channel - 1))) + *val = temp_from_reg_signed(data->temp[channel * 2], + data->temp[channel * 2 + 1]); + else + *val = temp_from_reg_unsigned(data->temp[channel * 2], + data->temp[channel * 2 + 1]); + return 0; + case hwmon_temp_min: + if (channel == 1) + *val = (data->config & R1DF_MASK) ? -128000 : 0; + else + *val = (data->config & R2DF_MASK) ? -128000 : 0; + return 0; + case hwmon_temp_max: + if (channel == 1) + *val = (data->config & R1DF_MASK) ? 127875 : 255875; + else + *val = (data->config & R2DF_MASK) ? 127875 : 255875; + return 0; + case hwmon_temp_type: + if (channel == 1) + *val = (data->model & R1MS_MASK) ? 1 : 2; + else + *val = (data->model & R2MS_MASK) ? 1 : 2; + return 0; + case hwmon_temp_fault: + if (channel == 1) + *val = !!(data->status & R1DM); + else + *val = !!(data->status & R2DM); + return 0; + default: + return -EOPNOTSUPP; + } +} + +static int lm95241_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + switch (type) { + case hwmon_chip: + return lm95241_read_chip(dev, attr, channel, val); + case hwmon_temp: + return lm95241_read_temp(dev, attr, channel, val); + default: + return -EOPNOTSUPP; + } +} + +static int lm95241_write_chip(struct device *dev, u32 attr, int channel, + long val) +{ + struct lm95241_data *data = dev_get_drvdata(dev); + int convrate; + u8 config; + int ret; + + mutex_lock(&data->update_lock); + + switch (attr) { + case hwmon_chip_update_interval: + config = data->config & ~CFG_CRMASK; + if (val < 130) { + convrate = 76; + config |= CFG_CR0076; + } else if (val < 590) { + convrate = 182; + config |= CFG_CR0182; + } else if (val < 1850) { + convrate = 1000; + config |= CFG_CR1000; + } else { + convrate = 2700; + config |= CFG_CR2700; + } + data->interval = convrate; + data->config = config; + ret = i2c_smbus_write_byte_data(data->client, + LM95241_REG_RW_CONFIG, config); + break; + default: + ret = -EOPNOTSUPP; + break; + } + mutex_unlock(&data->update_lock); + return ret; +} + +static int lm95241_write_temp(struct device *dev, u32 attr, int channel, + long val) +{ + struct lm95241_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + int ret; + + mutex_lock(&data->update_lock); + + switch (attr) { + case hwmon_temp_min: + if (channel == 1) { + if (val < 0) + data->config |= R1DF_MASK; + else + data->config &= ~R1DF_MASK; + } else { + if (val < 0) + data->config |= R2DF_MASK; + else + data->config &= ~R2DF_MASK; + } + data->valid = false; + ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, + data->config); + break; + case hwmon_temp_max: + if (channel == 1) { + if (val <= 127875) + data->config |= R1DF_MASK; + else + data->config &= ~R1DF_MASK; + } else { + if (val <= 127875) + data->config |= R2DF_MASK; + else + data->config &= ~R2DF_MASK; + } + data->valid = false; + ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, + data->config); + break; + case hwmon_temp_type: + if (val != 1 && val != 2) { + ret = -EINVAL; + break; + } + if (channel == 1) { + data->trutherm &= ~(TT_MASK << TT1_SHIFT); + if (val == 1) { + data->model |= R1MS_MASK; + data->trutherm |= (TT_ON << TT1_SHIFT); + } else { + data->model &= ~R1MS_MASK; + data->trutherm |= (TT_OFF << TT1_SHIFT); + } + } else { + data->trutherm &= ~(TT_MASK << TT2_SHIFT); + if (val == 1) { + data->model |= R2MS_MASK; + data->trutherm |= (TT_ON << TT2_SHIFT); + } else { + data->model &= ~R2MS_MASK; + data->trutherm |= (TT_OFF << TT2_SHIFT); + } + } + ret = i2c_smbus_write_byte_data(client, + LM95241_REG_RW_REMOTE_MODEL, + data->model); + if (ret < 0) + break; + ret = i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, + data->trutherm); + break; + default: + ret = -EOPNOTSUPP; + break; + } + + mutex_unlock(&data->update_lock); + + return ret; +} + +static int lm95241_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long val) +{ + switch (type) { + case hwmon_chip: + return lm95241_write_chip(dev, attr, channel, val); + case hwmon_temp: + return lm95241_write_temp(dev, attr, channel, val); + default: + return -EOPNOTSUPP; + } +} + +static umode_t lm95241_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 0644; + } + break; + case hwmon_temp: + switch (attr) { + case hwmon_temp_input: + return 0444; + case hwmon_temp_fault: + return 0444; + case hwmon_temp_min: + case hwmon_temp_max: + case hwmon_temp_type: + return 0644; + } + break; + default: + break; + } + return 0; +} + +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int lm95241_detect(struct i2c_client *new_client, + struct i2c_board_info *info) +{ + struct i2c_adapter *adapter = new_client->adapter; + const char *name; + int mfg_id, chip_id; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) + return -ENODEV; + + mfg_id = i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID); + if (mfg_id != NATSEMI_MAN_ID) + return -ENODEV; + + chip_id = i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID); + switch (chip_id) { + case LM95231_CHIP_ID: + name = "lm95231"; + break; + case LM95241_CHIP_ID: + name = "lm95241"; + break; + default: + return -ENODEV; + } + + /* Fill the i2c board info */ + strscpy(info->type, name, I2C_NAME_SIZE); + return 0; +} + +static void lm95241_init_client(struct i2c_client *client, + struct lm95241_data *data) +{ + data->interval = 1000; + data->config = CFG_CR1000; + data->trutherm = (TT_OFF << TT1_SHIFT) | (TT_OFF << TT2_SHIFT); + + i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, data->config); + i2c_smbus_write_byte_data(client, LM95241_REG_RW_REM_FILTER, + R1FE_MASK | R2FE_MASK); + i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, + data->trutherm); + i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, + data->model); +} + +static const struct hwmon_channel_info *lm95241_info[] = { + HWMON_CHANNEL_INFO(chip, + HWMON_C_UPDATE_INTERVAL), + HWMON_CHANNEL_INFO(temp, + HWMON_T_INPUT, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_TYPE | HWMON_T_FAULT, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_TYPE | HWMON_T_FAULT), + NULL +}; + +static const struct hwmon_ops lm95241_hwmon_ops = { + .is_visible = lm95241_is_visible, + .read = lm95241_read, + .write = lm95241_write, +}; + +static const struct hwmon_chip_info lm95241_chip_info = { + .ops = &lm95241_hwmon_ops, + .info = lm95241_info, +}; + +static int lm95241_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct lm95241_data *data; + struct device *hwmon_dev; + + data = devm_kzalloc(dev, sizeof(struct lm95241_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + mutex_init(&data->update_lock); + + /* Initialize the LM95241 chip */ + lm95241_init_client(client, data); + + hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, + data, + &lm95241_chip_info, + NULL); + return PTR_ERR_OR_ZERO(hwmon_dev); +} + +/* Driver data (common to all clients) */ +static const struct i2c_device_id lm95241_id[] = { + { "lm95231", 0 }, + { "lm95241", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, lm95241_id); + +static struct i2c_driver lm95241_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = DEVNAME, + }, + .probe_new = lm95241_probe, + .id_table = lm95241_id, + .detect = lm95241_detect, + .address_list = normal_i2c, +}; + +module_i2c_driver(lm95241_driver); + +MODULE_AUTHOR("Davide Rizzo <elpa.rizzo@gmail.com>"); +MODULE_DESCRIPTION("LM95231/LM95241 sensor driver"); +MODULE_LICENSE("GPL"); |