diff options
Diffstat (limited to 'kernel/drivers/hwmon/lm95245.c')
| -rw-r--r-- | kernel/drivers/hwmon/lm95245.c | 520 |
1 files changed, 520 insertions, 0 deletions
diff --git a/kernel/drivers/hwmon/lm95245.c b/kernel/drivers/hwmon/lm95245.c new file mode 100644 index 000000000..e7aef4561 --- /dev/null +++ b/kernel/drivers/hwmon/lm95245.c @@ -0,0 +1,520 @@ +/* + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/jiffies.h> +#include <linux/i2c.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/err.h> +#include <linux/mutex.h> +#include <linux/sysfs.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_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 i2c_client *client; + struct mutex update_lock; + unsigned long last_updated; /* in jiffies */ + unsigned long interval; /* in msecs */ + bool valid; /* zero until following fields are valid */ + /* registers values */ + u8 regs[ARRAY_SIZE(lm95245_reg_address)]; + u8 config1, config2; +}; + +/* 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 struct lm95245_data *lm95245_update_device(struct device *dev) +{ + struct lm95245_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; + + for (i = 0; i < ARRAY_SIZE(lm95245_reg_address); i++) + data->regs[i] + = i2c_smbus_read_byte_data(client, + lm95245_reg_address[i]); + data->last_updated = jiffies; + data->valid = 1; + } + + mutex_unlock(&data->update_lock); + + return data; +} + +static unsigned long lm95245_read_conversion_rate(struct i2c_client *client) +{ + int rate; + unsigned long interval; + + rate = i2c_smbus_read_byte_data(client, LM95245_REG_RW_CONVERS_RATE); + + switch (rate) { + case RATE_CR0063: + interval = 63; + break; + case RATE_CR0364: + interval = 364; + break; + case RATE_CR1000: + interval = 1000; + break; + case RATE_CR2500: + default: + interval = 2500; + break; + } + + return interval; +} + +static unsigned long lm95245_set_conversion_rate(struct i2c_client *client, + unsigned long interval) +{ + int 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; + } + + i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONVERS_RATE, rate); + + return interval; +} + +/* Sysfs stuff */ +static ssize_t show_input(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct lm95245_data *data = lm95245_update_device(dev); + int temp; + int index = to_sensor_dev_attr(attr)->index; + + /* + * Index 0 (Local temp) is always signed + * Index 2 (Remote temp) has both signed and unsigned data + * use signed calculation for remote if signed bit is set + */ + if (index == 0 || data->regs[index] & 0x80) + temp = temp_from_reg_signed(data->regs[index], + data->regs[index + 1]); + else + temp = temp_from_reg_unsigned(data->regs[index + 2], + data->regs[index + 3]); + + return snprintf(buf, PAGE_SIZE - 1, "%d\n", temp); +} + +static ssize_t show_limit(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct lm95245_data *data = lm95245_update_device(dev); + int index = to_sensor_dev_attr(attr)->index; + + return snprintf(buf, PAGE_SIZE - 1, "%d\n", + data->regs[index] * 1000); +} + +static ssize_t set_limit(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct lm95245_data *data = dev_get_drvdata(dev); + int index = to_sensor_dev_attr(attr)->index; + struct i2c_client *client = data->client; + unsigned long val; + + if (kstrtoul(buf, 10, &val) < 0) + return -EINVAL; + + val /= 1000; + + val = clamp_val(val, 0, (index == 6 ? 127 : 255)); + + mutex_lock(&data->update_lock); + + data->valid = 0; + + i2c_smbus_write_byte_data(client, lm95245_reg_address[index], val); + + mutex_unlock(&data->update_lock); + + return count; +} + +static ssize_t show_crit_hyst(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct lm95245_data *data = lm95245_update_device(dev); + int index = to_sensor_dev_attr(attr)->index; + int hyst = data->regs[index] - data->regs[8]; + + return snprintf(buf, PAGE_SIZE - 1, "%d\n", hyst * 1000); +} + +static ssize_t set_crit_hyst(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct lm95245_data *data = dev_get_drvdata(dev); + int index = to_sensor_dev_attr(attr)->index; + struct i2c_client *client = data->client; + unsigned long val; + int hyst, limit; + + if (kstrtoul(buf, 10, &val) < 0) + return -EINVAL; + + mutex_lock(&data->update_lock); + + limit = i2c_smbus_read_byte_data(client, lm95245_reg_address[index]); + hyst = limit - val / 1000; + hyst = clamp_val(hyst, 0, 31); + data->regs[8] = hyst; + + /* shared crit hysteresis */ + i2c_smbus_write_byte_data(client, LM95245_REG_RW_COMMON_HYSTERESIS, + hyst); + + mutex_unlock(&data->update_lock); + + return count; +} + +static ssize_t show_type(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct lm95245_data *data = dev_get_drvdata(dev); + + return snprintf(buf, PAGE_SIZE - 1, + data->config2 & CFG2_REMOTE_TT ? "1\n" : "2\n"); +} + +static ssize_t set_type(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct lm95245_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + unsigned long val; + + if (kstrtoul(buf, 10, &val) < 0) + return -EINVAL; + if (val != 1 && val != 2) + return -EINVAL; + + mutex_lock(&data->update_lock); + + if (val == 1) + data->config2 |= CFG2_REMOTE_TT; + else + data->config2 &= ~CFG2_REMOTE_TT; + + data->valid = 0; + + i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONFIG2, + data->config2); + + mutex_unlock(&data->update_lock); + + return count; +} + +static ssize_t show_alarm(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct lm95245_data *data = lm95245_update_device(dev); + int index = to_sensor_dev_attr(attr)->index; + + return snprintf(buf, PAGE_SIZE - 1, "%d\n", + !!(data->regs[9] & index)); +} + +static ssize_t show_interval(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct lm95245_data *data = lm95245_update_device(dev); + + return snprintf(buf, PAGE_SIZE - 1, "%lu\n", data->interval); +} + +static ssize_t set_interval(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct lm95245_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + unsigned long val; + + if (kstrtoul(buf, 10, &val) < 0) + return -EINVAL; + + mutex_lock(&data->update_lock); + + data->interval = lm95245_set_conversion_rate(client, val); + + mutex_unlock(&data->update_lock); + + return count; +} + +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_input, NULL, 0); +static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO, show_limit, + set_limit, 6); +static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO, show_crit_hyst, + set_crit_hyst, 6); +static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, + STATUS1_LOC); + +static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_input, NULL, 2); +static SENSOR_DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_limit, + set_limit, 7); +static SENSOR_DEVICE_ATTR(temp2_crit_hyst, S_IRUGO, show_crit_hyst, NULL, 7); +static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, + STATUS1_RTCRIT); +static SENSOR_DEVICE_ATTR(temp2_type, S_IWUSR | S_IRUGO, show_type, + set_type, 0); +static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, + STATUS1_DIODE_FAULT); + +static DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO, show_interval, + set_interval); + +static struct attribute *lm95245_attrs[] = { + &sensor_dev_attr_temp1_input.dev_attr.attr, + &sensor_dev_attr_temp1_crit.dev_attr.attr, + &sensor_dev_attr_temp1_crit_hyst.dev_attr.attr, + &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, + &sensor_dev_attr_temp2_input.dev_attr.attr, + &sensor_dev_attr_temp2_crit.dev_attr.attr, + &sensor_dev_attr_temp2_crit_hyst.dev_attr.attr, + &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, + &sensor_dev_attr_temp2_type.dev_attr.attr, + &sensor_dev_attr_temp2_fault.dev_attr.attr, + &dev_attr_update_interval.attr, + NULL +}; +ATTRIBUTE_GROUPS(lm95245); + +/* 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 void lm95245_init_client(struct i2c_client *client, + struct lm95245_data *data) +{ + data->interval = lm95245_read_conversion_rate(client); + + data->config1 = i2c_smbus_read_byte_data(client, + LM95245_REG_RW_CONFIG1); + data->config2 = i2c_smbus_read_byte_data(client, + LM95245_REG_RW_CONFIG2); + + if (data->config1 & CFG_STOP) { + /* Clear the standby bit */ + data->config1 &= ~CFG_STOP; + i2c_smbus_write_byte_data(client, LM95245_REG_RW_CONFIG1, + data->config1); + } +} + +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; + + data = devm_kzalloc(dev, sizeof(struct lm95245_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->client = client; + mutex_init(&data->update_lock); + + /* Initialize the LM95245 chip */ + lm95245_init_client(client, data); + + hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, + data, + lm95245_groups); + 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 struct i2c_driver lm95245_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "lm95245", + }, + .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"); |