/* * Driver for the Texas Instruments / Burr Brown INA209 * Bidirectional Current/Power Monitor * * Copyright (C) 2012 Guenter Roeck * * Derived from Ira W. Snyder's original driver submission * Copyright (C) 2008 Paul Hays * Copyright (C) 2008-2009 Ira W. Snyder * * Aligned with ina2xx driver * Copyright (C) 2012 Lothar Felten * 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 #include #include #include #include #include #include #include #include #include /* 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 device *hwmon_dev; 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 i2c_client *client = to_i2c_client(dev); struct ina209_data *data = i2c_get_clientdata(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(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 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 i2c_client *client = to_i2c_client(dev); 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(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 i2c_client *client = to_i2c_client(dev); struct ina209_data *data = i2c_get_clientdata(client); 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 i2c_client *client = to_i2c_client(dev); struct ina209_data *data = i2c_get_clientdata(client); struct sensor_device_attribute *attr = to_sensor_dev_attr(da); 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 i2c_client *client = to_i2c_client(dev); 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(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_attributes[] = { &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, }; static const struct attribute_group ina209_group = { .attrs = ina209_attributes, }; 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; 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); mutex_init(&data->update_lock); ret = ina209_init_client(client, data); if (ret) return ret; /* Register sysfs hooks */ ret = sysfs_create_group(&client->dev.kobj, &ina209_group); if (ret) goto out_restore_conf; data->hwmon_dev = hwmon_device_register(&client->dev); if (IS_ERR(data->hwmon_dev)) { ret = PTR_ERR(data->hwmon_dev); goto out_hwmon_device_register; } return 0; out_hwmon_device_register: sysfs_remove_group(&client->dev.kobj, &ina209_group); 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); hwmon_device_unregister(data->hwmon_dev); sysfs_remove_group(&client->dev.kobj, &ina209_group); ina209_restore_conf(client, data); return 0; } static const struct i2c_device_id ina209_id[] = { { "ina209", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, ina209_id); /* This is the driver that will be inserted */ static struct i2c_driver ina209_driver = { .class = I2C_CLASS_HWMON, .driver = { .name = "ina209", }, .probe = ina209_probe, .remove = ina209_remove, .id_table = ina209_id, }; module_i2c_driver(ina209_driver); MODULE_AUTHOR("Ira W. Snyder , Paul Hays , Guenter Roeck "); MODULE_DESCRIPTION("INA209 driver"); MODULE_LICENSE("GPL");