diff options
Diffstat (limited to 'drivers/hwmon/ina209.c')
| -rw-r--r-- | drivers/hwmon/ina209.c | 633 |
1 files changed, 633 insertions, 0 deletions
diff --git a/drivers/hwmon/ina209.c b/drivers/hwmon/ina209.c new file mode 100644 index 000000000..aa0768ce8 --- /dev/null +++ b/drivers/hwmon/ina209.c @@ -0,0 +1,633 @@ +/* + * Driver for the Texas Instruments / Burr Brown INA209 + * Bidirectional Current/Power Monitor + * + * Copyright (C) 2012 Guenter Roeck <linux@roeck-us.net> + * + * Derived from Ira W. Snyder's original driver submission + * Copyright (C) 2008 Paul Hays <Paul.Hays@cattail.ca> + * Copyright (C) 2008-2009 Ira W. Snyder <iws@ovro.caltech.edu> + * + * Aligned with ina2xx driver + * Copyright (C) 2012 Lothar Felten <l-felten@ti.com> + * Thanks to Jan Volkering + * + * 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; version 2 of the License. + * + * Datasheet: + * http://www.ti.com/lit/gpn/ina209 + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/bug.h> +#include <linux/i2c.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> + +#include <linux/platform_data/ina2xx.h> + +/* register definitions */ +#define INA209_CONFIGURATION 0x00 +#define INA209_STATUS 0x01 +#define INA209_STATUS_MASK 0x02 +#define INA209_SHUNT_VOLTAGE 0x03 +#define INA209_BUS_VOLTAGE 0x04 +#define INA209_POWER 0x05 +#define INA209_CURRENT 0x06 +#define INA209_SHUNT_VOLTAGE_POS_PEAK 0x07 +#define INA209_SHUNT_VOLTAGE_NEG_PEAK 0x08 +#define INA209_BUS_VOLTAGE_MAX_PEAK 0x09 +#define INA209_BUS_VOLTAGE_MIN_PEAK 0x0a +#define INA209_POWER_PEAK 0x0b +#define INA209_SHUNT_VOLTAGE_POS_WARN 0x0c +#define INA209_SHUNT_VOLTAGE_NEG_WARN 0x0d +#define INA209_POWER_WARN 0x0e +#define INA209_BUS_VOLTAGE_OVER_WARN 0x0f +#define INA209_BUS_VOLTAGE_UNDER_WARN 0x10 +#define INA209_POWER_OVER_LIMIT 0x11 +#define INA209_BUS_VOLTAGE_OVER_LIMIT 0x12 +#define INA209_BUS_VOLTAGE_UNDER_LIMIT 0x13 +#define INA209_CRITICAL_DAC_POS 0x14 +#define INA209_CRITICAL_DAC_NEG 0x15 +#define INA209_CALIBRATION 0x16 + +#define INA209_REGISTERS 0x17 + +#define INA209_CONFIG_DEFAULT 0x3c47 /* PGA=8, full range */ +#define INA209_SHUNT_DEFAULT 10000 /* uOhm */ + +struct ina209_data { + struct i2c_client *client; + + struct mutex update_lock; + bool valid; + unsigned long last_updated; /* in jiffies */ + + u16 regs[INA209_REGISTERS]; /* All chip registers */ + + u16 config_orig; /* Original configuration */ + u16 calibration_orig; /* Original calibration */ + u16 update_interval; +}; + +static struct ina209_data *ina209_update_device(struct device *dev) +{ + struct ina209_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + struct ina209_data *ret = data; + s32 val; + int i; + + mutex_lock(&data->update_lock); + + if (!data->valid || + time_after(jiffies, data->last_updated + data->update_interval)) { + for (i = 0; i < ARRAY_SIZE(data->regs); i++) { + val = i2c_smbus_read_word_swapped(client, i); + if (val < 0) { + ret = ERR_PTR(val); + goto abort; + } + data->regs[i] = val; + } + data->last_updated = jiffies; + data->valid = true; + } +abort: + mutex_unlock(&data->update_lock); + return ret; +} + +/* + * Read a value from a device register and convert it to the + * appropriate sysfs units + */ +static long ina209_from_reg(const u8 reg, const u16 val) +{ + switch (reg) { + case INA209_SHUNT_VOLTAGE: + case INA209_SHUNT_VOLTAGE_POS_PEAK: + case INA209_SHUNT_VOLTAGE_NEG_PEAK: + case INA209_SHUNT_VOLTAGE_POS_WARN: + case INA209_SHUNT_VOLTAGE_NEG_WARN: + /* LSB=10 uV. Convert to mV. */ + return DIV_ROUND_CLOSEST((s16)val, 100); + + case INA209_BUS_VOLTAGE: + case INA209_BUS_VOLTAGE_MAX_PEAK: + case INA209_BUS_VOLTAGE_MIN_PEAK: + case INA209_BUS_VOLTAGE_OVER_WARN: + case INA209_BUS_VOLTAGE_UNDER_WARN: + case INA209_BUS_VOLTAGE_OVER_LIMIT: + case INA209_BUS_VOLTAGE_UNDER_LIMIT: + /* LSB=4 mV, last 3 bits unused */ + return (val >> 3) * 4; + + case INA209_CRITICAL_DAC_POS: + /* LSB=1 mV, in the upper 8 bits */ + return val >> 8; + + case INA209_CRITICAL_DAC_NEG: + /* LSB=1 mV, in the upper 8 bits */ + return -1 * (val >> 8); + + case INA209_POWER: + case INA209_POWER_PEAK: + case INA209_POWER_WARN: + case INA209_POWER_OVER_LIMIT: + /* LSB=20 mW. Convert to uW */ + return val * 20 * 1000L; + + case INA209_CURRENT: + /* LSB=1 mA (selected). Is in mA */ + return (s16)val; + } + + /* programmer goofed */ + WARN_ON_ONCE(1); + return 0; +} + +/* + * Take a value and convert it to register format, clamping the value + * to the appropriate range. + */ +static int ina209_to_reg(u8 reg, u16 old, long val) +{ + switch (reg) { + case INA209_SHUNT_VOLTAGE_POS_WARN: + case INA209_SHUNT_VOLTAGE_NEG_WARN: + /* Limit to +- 320 mV, 10 uV LSB */ + return clamp_val(val, -320, 320) * 100; + + case INA209_BUS_VOLTAGE_OVER_WARN: + case INA209_BUS_VOLTAGE_UNDER_WARN: + case INA209_BUS_VOLTAGE_OVER_LIMIT: + case INA209_BUS_VOLTAGE_UNDER_LIMIT: + /* + * Limit to 0-32000 mV, 4 mV LSB + * + * The last three bits aren't part of the value, but we'll + * preserve them in their original state. + */ + return (DIV_ROUND_CLOSEST(clamp_val(val, 0, 32000), 4) << 3) + | (old & 0x7); + + case INA209_CRITICAL_DAC_NEG: + /* + * Limit to -255-0 mV, 1 mV LSB + * Convert the value to a positive value for the register + * + * The value lives in the top 8 bits only, be careful + * and keep original value of other bits. + */ + return (clamp_val(-val, 0, 255) << 8) | (old & 0xff); + + case INA209_CRITICAL_DAC_POS: + /* + * Limit to 0-255 mV, 1 mV LSB + * + * The value lives in the top 8 bits only, be careful + * and keep original value of other bits. + */ + return (clamp_val(val, 0, 255) << 8) | (old & 0xff); + + case INA209_POWER_WARN: + case INA209_POWER_OVER_LIMIT: + /* 20 mW LSB */ + return DIV_ROUND_CLOSEST(val, 20 * 1000); + } + + /* Other registers are read-only, return access error */ + return -EACCES; +} + +static int ina209_interval_from_reg(u16 reg) +{ + return 68 >> (15 - ((reg >> 3) & 0x0f)); +} + +static u16 ina209_reg_from_interval(u16 config, long interval) +{ + int i, adc; + + if (interval <= 0) { + adc = 8; + } else { + adc = 15; + for (i = 34 + 34 / 2; i; i >>= 1) { + if (i < interval) + break; + adc--; + } + } + return (config & 0xf807) | (adc << 3) | (adc << 7); +} + +static ssize_t ina209_set_interval(struct device *dev, + struct device_attribute *da, + const char *buf, size_t count) +{ + struct ina209_data *data = ina209_update_device(dev); + long val; + u16 regval; + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + ret = kstrtol(buf, 10, &val); + if (ret < 0) + return ret; + + mutex_lock(&data->update_lock); + regval = ina209_reg_from_interval(data->regs[INA209_CONFIGURATION], + val); + i2c_smbus_write_word_swapped(data->client, INA209_CONFIGURATION, + regval); + data->regs[INA209_CONFIGURATION] = regval; + data->update_interval = ina209_interval_from_reg(regval); + mutex_unlock(&data->update_lock); + return count; +} + +static ssize_t ina209_show_interval(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct ina209_data *data = dev_get_drvdata(dev); + + return snprintf(buf, PAGE_SIZE, "%d\n", data->update_interval); +} + +/* + * History is reset by writing 1 into bit 0 of the respective peak register. + * Since more than one peak register may be affected by the scope of a + * reset_history attribute write, use a bit mask in attr->index to identify + * which registers are affected. + */ +static u16 ina209_reset_history_regs[] = { + INA209_SHUNT_VOLTAGE_POS_PEAK, + INA209_SHUNT_VOLTAGE_NEG_PEAK, + INA209_BUS_VOLTAGE_MAX_PEAK, + INA209_BUS_VOLTAGE_MIN_PEAK, + INA209_POWER_PEAK +}; + +static ssize_t ina209_reset_history(struct device *dev, + struct device_attribute *da, + const char *buf, + size_t count) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct ina209_data *data = dev_get_drvdata(dev); + struct i2c_client *client = data->client; + u32 mask = attr->index; + long val; + int i, ret; + + ret = kstrtol(buf, 10, &val); + if (ret < 0) + return ret; + + mutex_lock(&data->update_lock); + for (i = 0; i < ARRAY_SIZE(ina209_reset_history_regs); i++) { + if (mask & (1 << i)) + i2c_smbus_write_word_swapped(client, + ina209_reset_history_regs[i], 1); + } + data->valid = false; + mutex_unlock(&data->update_lock); + return count; +} + +static ssize_t ina209_set_value(struct device *dev, + struct device_attribute *da, + const char *buf, + size_t count) +{ + struct ina209_data *data = ina209_update_device(dev); + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + int reg = attr->index; + long val; + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + ret = kstrtol(buf, 10, &val); + if (ret < 0) + return ret; + + mutex_lock(&data->update_lock); + ret = ina209_to_reg(reg, data->regs[reg], val); + if (ret < 0) { + count = ret; + goto abort; + } + i2c_smbus_write_word_swapped(data->client, reg, ret); + data->regs[reg] = ret; +abort: + mutex_unlock(&data->update_lock); + return count; +} + +static ssize_t ina209_show_value(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct ina209_data *data = ina209_update_device(dev); + long val; + + if (IS_ERR(data)) + return PTR_ERR(data); + + val = ina209_from_reg(attr->index, data->regs[attr->index]); + return snprintf(buf, PAGE_SIZE, "%ld\n", val); +} + +static ssize_t ina209_show_alarm(struct device *dev, + struct device_attribute *da, + char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct ina209_data *data = ina209_update_device(dev); + const unsigned int mask = attr->index; + u16 status; + + if (IS_ERR(data)) + return PTR_ERR(data); + + status = data->regs[INA209_STATUS]; + + /* + * All alarms are in the INA209_STATUS register. To avoid a long + * switch statement, the mask is passed in attr->index + */ + return snprintf(buf, PAGE_SIZE, "%u\n", !!(status & mask)); +} + +/* Shunt voltage, history, limits, alarms */ +static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ina209_show_value, NULL, + INA209_SHUNT_VOLTAGE); +static SENSOR_DEVICE_ATTR(in0_input_highest, S_IRUGO, ina209_show_value, NULL, + INA209_SHUNT_VOLTAGE_POS_PEAK); +static SENSOR_DEVICE_ATTR(in0_input_lowest, S_IRUGO, ina209_show_value, NULL, + INA209_SHUNT_VOLTAGE_NEG_PEAK); +static SENSOR_DEVICE_ATTR(in0_reset_history, S_IWUSR, NULL, + ina209_reset_history, (1 << 0) | (1 << 1)); +static SENSOR_DEVICE_ATTR(in0_max, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_SHUNT_VOLTAGE_POS_WARN); +static SENSOR_DEVICE_ATTR(in0_min, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_SHUNT_VOLTAGE_NEG_WARN); +static SENSOR_DEVICE_ATTR(in0_crit_max, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_CRITICAL_DAC_POS); +static SENSOR_DEVICE_ATTR(in0_crit_min, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_CRITICAL_DAC_NEG); + +static SENSOR_DEVICE_ATTR(in0_min_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 11); +static SENSOR_DEVICE_ATTR(in0_max_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 12); +static SENSOR_DEVICE_ATTR(in0_crit_min_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 6); +static SENSOR_DEVICE_ATTR(in0_crit_max_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 7); + +/* Bus voltage, history, limits, alarms */ +static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ina209_show_value, NULL, + INA209_BUS_VOLTAGE); +static SENSOR_DEVICE_ATTR(in1_input_highest, S_IRUGO, ina209_show_value, NULL, + INA209_BUS_VOLTAGE_MAX_PEAK); +static SENSOR_DEVICE_ATTR(in1_input_lowest, S_IRUGO, ina209_show_value, NULL, + INA209_BUS_VOLTAGE_MIN_PEAK); +static SENSOR_DEVICE_ATTR(in1_reset_history, S_IWUSR, NULL, + ina209_reset_history, (1 << 2) | (1 << 3)); +static SENSOR_DEVICE_ATTR(in1_max, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_BUS_VOLTAGE_OVER_WARN); +static SENSOR_DEVICE_ATTR(in1_min, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_BUS_VOLTAGE_UNDER_WARN); +static SENSOR_DEVICE_ATTR(in1_crit_max, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_BUS_VOLTAGE_OVER_LIMIT); +static SENSOR_DEVICE_ATTR(in1_crit_min, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_BUS_VOLTAGE_UNDER_LIMIT); + +static SENSOR_DEVICE_ATTR(in1_min_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 14); +static SENSOR_DEVICE_ATTR(in1_max_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 15); +static SENSOR_DEVICE_ATTR(in1_crit_min_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 9); +static SENSOR_DEVICE_ATTR(in1_crit_max_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 10); + +/* Power */ +static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, ina209_show_value, NULL, + INA209_POWER); +static SENSOR_DEVICE_ATTR(power1_input_highest, S_IRUGO, ina209_show_value, + NULL, INA209_POWER_PEAK); +static SENSOR_DEVICE_ATTR(power1_reset_history, S_IWUSR, NULL, + ina209_reset_history, 1 << 4); +static SENSOR_DEVICE_ATTR(power1_max, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_POWER_WARN); +static SENSOR_DEVICE_ATTR(power1_crit, S_IRUGO | S_IWUSR, ina209_show_value, + ina209_set_value, INA209_POWER_OVER_LIMIT); + +static SENSOR_DEVICE_ATTR(power1_max_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 13); +static SENSOR_DEVICE_ATTR(power1_crit_alarm, S_IRUGO, ina209_show_alarm, NULL, + 1 << 8); + +/* Current */ +static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ina209_show_value, NULL, + INA209_CURRENT); + +static SENSOR_DEVICE_ATTR(update_interval, S_IRUGO | S_IWUSR, + ina209_show_interval, ina209_set_interval, 0); + +/* + * Finally, construct an array of pointers to members of the above objects, + * as required for sysfs_create_group() + */ +static struct attribute *ina209_attrs[] = { + &sensor_dev_attr_in0_input.dev_attr.attr, + &sensor_dev_attr_in0_input_highest.dev_attr.attr, + &sensor_dev_attr_in0_input_lowest.dev_attr.attr, + &sensor_dev_attr_in0_reset_history.dev_attr.attr, + &sensor_dev_attr_in0_max.dev_attr.attr, + &sensor_dev_attr_in0_min.dev_attr.attr, + &sensor_dev_attr_in0_crit_max.dev_attr.attr, + &sensor_dev_attr_in0_crit_min.dev_attr.attr, + &sensor_dev_attr_in0_max_alarm.dev_attr.attr, + &sensor_dev_attr_in0_min_alarm.dev_attr.attr, + &sensor_dev_attr_in0_crit_max_alarm.dev_attr.attr, + &sensor_dev_attr_in0_crit_min_alarm.dev_attr.attr, + + &sensor_dev_attr_in1_input.dev_attr.attr, + &sensor_dev_attr_in1_input_highest.dev_attr.attr, + &sensor_dev_attr_in1_input_lowest.dev_attr.attr, + &sensor_dev_attr_in1_reset_history.dev_attr.attr, + &sensor_dev_attr_in1_max.dev_attr.attr, + &sensor_dev_attr_in1_min.dev_attr.attr, + &sensor_dev_attr_in1_crit_max.dev_attr.attr, + &sensor_dev_attr_in1_crit_min.dev_attr.attr, + &sensor_dev_attr_in1_max_alarm.dev_attr.attr, + &sensor_dev_attr_in1_min_alarm.dev_attr.attr, + &sensor_dev_attr_in1_crit_max_alarm.dev_attr.attr, + &sensor_dev_attr_in1_crit_min_alarm.dev_attr.attr, + + &sensor_dev_attr_power1_input.dev_attr.attr, + &sensor_dev_attr_power1_input_highest.dev_attr.attr, + &sensor_dev_attr_power1_reset_history.dev_attr.attr, + &sensor_dev_attr_power1_max.dev_attr.attr, + &sensor_dev_attr_power1_crit.dev_attr.attr, + &sensor_dev_attr_power1_max_alarm.dev_attr.attr, + &sensor_dev_attr_power1_crit_alarm.dev_attr.attr, + + &sensor_dev_attr_curr1_input.dev_attr.attr, + + &sensor_dev_attr_update_interval.dev_attr.attr, + + NULL, +}; +ATTRIBUTE_GROUPS(ina209); + +static void ina209_restore_conf(struct i2c_client *client, + struct ina209_data *data) +{ + /* Restore initial configuration */ + i2c_smbus_write_word_swapped(client, INA209_CONFIGURATION, + data->config_orig); + i2c_smbus_write_word_swapped(client, INA209_CALIBRATION, + data->calibration_orig); +} + +static int ina209_init_client(struct i2c_client *client, + struct ina209_data *data) +{ + struct ina2xx_platform_data *pdata = dev_get_platdata(&client->dev); + u32 shunt; + int reg; + + reg = i2c_smbus_read_word_swapped(client, INA209_CALIBRATION); + if (reg < 0) + return reg; + data->calibration_orig = reg; + + reg = i2c_smbus_read_word_swapped(client, INA209_CONFIGURATION); + if (reg < 0) + return reg; + data->config_orig = reg; + + if (pdata) { + if (pdata->shunt_uohms <= 0) + return -EINVAL; + shunt = pdata->shunt_uohms; + } else if (!of_property_read_u32(client->dev.of_node, "shunt-resistor", + &shunt)) { + if (shunt == 0) + return -EINVAL; + } else { + shunt = data->calibration_orig ? + 40960000 / data->calibration_orig : INA209_SHUNT_DEFAULT; + } + + i2c_smbus_write_word_swapped(client, INA209_CONFIGURATION, + INA209_CONFIG_DEFAULT); + data->update_interval = ina209_interval_from_reg(INA209_CONFIG_DEFAULT); + + /* + * Calibrate current LSB to 1mA. Shunt is in uOhms. + * See equation 13 in datasheet. + */ + i2c_smbus_write_word_swapped(client, INA209_CALIBRATION, + clamp_val(40960000 / shunt, 1, 65535)); + + /* Clear status register */ + i2c_smbus_read_word_swapped(client, INA209_STATUS); + + return 0; +} + +static int ina209_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adapter = client->adapter; + struct ina209_data *data; + struct device *hwmon_dev; + int ret; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) + return -ENODEV; + + data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + i2c_set_clientdata(client, data); + data->client = client; + mutex_init(&data->update_lock); + + ret = ina209_init_client(client, data); + if (ret) + return ret; + + hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev, + client->name, + data, ina209_groups); + if (IS_ERR(hwmon_dev)) { + ret = PTR_ERR(hwmon_dev); + goto out_restore_conf; + } + + return 0; + +out_restore_conf: + ina209_restore_conf(client, data); + return ret; +} + +static int ina209_remove(struct i2c_client *client) +{ + struct ina209_data *data = i2c_get_clientdata(client); + + ina209_restore_conf(client, data); + + return 0; +} + +static const struct i2c_device_id ina209_id[] = { + { "ina209", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ina209_id); + +static const struct of_device_id ina209_of_match[] = { + { .compatible = "ti,ina209" }, + { }, +}; +MODULE_DEVICE_TABLE(of, ina209_of_match); + +/* This is the driver that will be inserted */ +static struct i2c_driver ina209_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "ina209", + .of_match_table = of_match_ptr(ina209_of_match), + }, + .probe = ina209_probe, + .remove = ina209_remove, + .id_table = ina209_id, +}; + +module_i2c_driver(ina209_driver); + +MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>, Paul Hays <Paul.Hays@cattail.ca>, Guenter Roeck <linux@roeck-us.net>"); +MODULE_DESCRIPTION("INA209 driver"); +MODULE_LICENSE("GPL"); |