diff options
| -rw-r--r-- | Documentation/hwmon/ina2xx | 29 | ||||
| -rw-r--r-- | drivers/hwmon/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/hwmon/Makefile | 1 | ||||
| -rw-r--r-- | drivers/hwmon/ina2xx.c | 368 | ||||
| -rw-r--r-- | include/linux/platform_data/ina2xx.h | 19 |
5 files changed, 430 insertions, 0 deletions
diff --git a/Documentation/hwmon/ina2xx b/Documentation/hwmon/ina2xx new file mode 100644 index 000000000000..f50a6cc27616 --- /dev/null +++ b/Documentation/hwmon/ina2xx @@ -0,0 +1,29 @@ +Kernel driver ina2xx +==================== + +Supported chips: + * Texas Instruments INA219 + Prefix: 'ina219' + Addresses: I2C 0x40 - 0x4f + Datasheet: Publicly available at the Texas Instruments website + http://www.ti.com/ + + * Texas Instruments INA226 + Prefix: 'ina226' + Addresses: I2C 0x40 - 0x4f + Datasheet: Publicly available at the Texas Instruments website + http://www.ti.com/ + +Author: Lothar Felten <l-felten@ti.com> + +Description +----------- + +The INA219 is a high-side current shunt and power monitor with an I2C +interface. The INA219 monitors both shunt drop and supply voltage, with +programmable conversion times and filtering. + +The INA226 is a current shunt and power monitor with an I2C interface. +The INA226 monitors both a shunt voltage drop and bus supply voltage. + +The shunt value in micro-ohms can be set via platform data. diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 8deedc1b9840..1c7bbd458902 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -1102,6 +1102,19 @@ config SENSORS_AMC6821 This driver can also be build as a module. If so, the module will be called amc6821. +config SENSORS_INA2XX + tristate "Texas Instruments INA219, INA226" + depends on I2C && EXPERIMENTAL + help + If you say yes here you get support for INA219 and INA226 power + monitor chips. + + The INA2xx driver is configured for the default configuration of + the part as described in the datasheet. + Default value for Rshunt is 10 mOhms. + This driver can also be built as a module. If so, the module + will be called ina2xx. + config SENSORS_THMC50 tristate "Texas Instruments THMC50 / Analog Devices ADM1022" depends on I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 6d3f11f71815..e1eeac13b851 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -62,6 +62,7 @@ obj-$(CONFIG_SENSORS_ULTRA45) += ultra45_env.o obj-$(CONFIG_SENSORS_I5K_AMB) += i5k_amb.o obj-$(CONFIG_SENSORS_IBMAEM) += ibmaem.o obj-$(CONFIG_SENSORS_IBMPEX) += ibmpex.o +obj-$(CONFIG_SENSORS_INA2XX) += ina2xx.o obj-$(CONFIG_SENSORS_IT87) += it87.o obj-$(CONFIG_SENSORS_JC42) += jc42.o obj-$(CONFIG_SENSORS_JZ4740) += jz4740-hwmon.o diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c new file mode 100644 index 000000000000..7f3f4a385729 --- /dev/null +++ b/drivers/hwmon/ina2xx.c @@ -0,0 +1,368 @@ +/* + * Driver for Texas Instruments INA219, INA226 power monitor chips + * + * INA219: + * Zero Drift Bi-Directional Current/Power Monitor with I2C Interface + * Datasheet: http://www.ti.com/product/ina219 + * + * INA226: + * Bi-Directional Current/Power Monitor with I2C Interface + * Datasheet: http://www.ti.com/product/ina226 + * + * 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. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> + +#include <linux/platform_data/ina2xx.h> + +/* common register definitions */ +#define INA2XX_CONFIG 0x00 +#define INA2XX_SHUNT_VOLTAGE 0x01 /* readonly */ +#define INA2XX_BUS_VOLTAGE 0x02 /* readonly */ +#define INA2XX_POWER 0x03 /* readonly */ +#define INA2XX_CURRENT 0x04 /* readonly */ +#define INA2XX_CALIBRATION 0x05 + +/* INA226 register definitions */ +#define INA226_MASK_ENABLE 0x06 +#define INA226_ALERT_LIMIT 0x07 +#define INA226_DIE_ID 0xFF + + +/* register count */ +#define INA219_REGISTERS 6 +#define INA226_REGISTERS 8 + +#define INA2XX_MAX_REGISTERS 8 + +/* settings - depend on use case */ +#define INA219_CONFIG_DEFAULT 0x399F /* PGA=8 */ +#define INA226_CONFIG_DEFAULT 0x4527 /* averages=16 */ + +/* worst case is 68.10 ms (~14.6Hz, ina219) */ +#define INA2XX_CONVERSION_RATE 15 + +enum ina2xx_ids { ina219, ina226 }; + +struct ina2xx_data { + struct device *hwmon_dev; + + struct mutex update_lock; + bool valid; + unsigned long last_updated; + + int kind; + int registers; + u16 regs[INA2XX_MAX_REGISTERS]; +}; + +int ina2xx_read_word(struct i2c_client *client, int reg) +{ + int val = i2c_smbus_read_word_data(client, reg); + if (unlikely(val < 0)) { + dev_dbg(&client->dev, + "Failed to read register: %d\n", reg); + return val; + } + return be16_to_cpu(val); +} + +void ina2xx_write_word(struct i2c_client *client, int reg, int data) +{ + i2c_smbus_write_word_data(client, reg, cpu_to_be16(data)); +} + +static struct ina2xx_data *ina2xx_update_device(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct ina2xx_data *data = i2c_get_clientdata(client); + struct ina2xx_data *ret = data; + + mutex_lock(&data->update_lock); + + if (time_after(jiffies, data->last_updated + + HZ / INA2XX_CONVERSION_RATE) || !data->valid) { + + int i; + + dev_dbg(&client->dev, "Starting ina2xx update\n"); + + /* Read all registers */ + for (i = 0; i < data->registers; i++) { + int rv = ina2xx_read_word(client, i); + if (rv < 0) { + ret = ERR_PTR(rv); + goto abort; + } + data->regs[i] = rv; + } + data->last_updated = jiffies; + data->valid = 1; + } +abort: + mutex_unlock(&data->update_lock); + return ret; +} + +static int ina219_get_value(struct ina2xx_data *data, u8 reg) +{ + /* + * calculate exact value for the given register + * we assume default power-on reset settings: + * bus voltage range 32V + * gain = /8 + * adc 1 & 2 -> conversion time 532uS + * mode is continuous shunt and bus + * calibration value is INA219_CALIBRATION_VALUE + */ + int val = data->regs[reg]; + + switch (reg) { + case INA2XX_SHUNT_VOLTAGE: + /* LSB=10uV. Convert to mV. */ + val = DIV_ROUND_CLOSEST(val, 100); + break; + case INA2XX_BUS_VOLTAGE: + /* LSB=4mV. Register is not right aligned, convert to mV. */ + val = (val >> 3) * 4; + break; + case INA2XX_POWER: + /* LSB=20mW. Convert to uW */ + val = val * 20 * 1000; + break; + case INA2XX_CURRENT: + /* LSB=1mA (selected). Is in mA */ + break; + default: + /* programmer goofed */ + WARN_ON_ONCE(1); + val = 0; + break; + } + + return val; +} + +static int ina226_get_value(struct ina2xx_data *data, u8 reg) +{ + /* + * calculate exact value for the given register + * we assume default power-on reset settings: + * bus voltage range 32V + * gain = /8 + * adc 1 & 2 -> conversion time 532uS + * mode is continuous shunt and bus + * calibration value is INA226_CALIBRATION_VALUE + */ + int val = data->regs[reg]; + + switch (reg) { + case INA2XX_SHUNT_VOLTAGE: + /* LSB=2.5uV. Convert to mV. */ + val = DIV_ROUND_CLOSEST(val, 400); + break; + case INA2XX_BUS_VOLTAGE: + /* LSB=1.25mV. Convert to mV. */ + val = val + DIV_ROUND_CLOSEST(val, 4); + break; + case INA2XX_POWER: + /* LSB=25mW. Convert to uW */ + val = val * 25 * 1000; + break; + case INA2XX_CURRENT: + /* LSB=1mA (selected). Is in mA */ + break; + default: + /* programmer goofed */ + WARN_ON_ONCE(1); + val = 0; + break; + } + + return val; +} + +static ssize_t ina2xx_show_value(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct ina2xx_data *data = ina2xx_update_device(dev); + int value = 0; + + if (IS_ERR(data)) + return PTR_ERR(data); + + switch (data->kind) { + case ina219: + value = ina219_get_value(data, attr->index); + break; + case ina226: + value = ina226_get_value(data, attr->index); + break; + default: + WARN_ON_ONCE(1); + break; + } + return snprintf(buf, PAGE_SIZE, "%d\n", value); +} + +/* shunt voltage */ +static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, \ + ina2xx_show_value, NULL, INA2XX_SHUNT_VOLTAGE); + +/* bus voltage */ +static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, \ + ina2xx_show_value, NULL, INA2XX_BUS_VOLTAGE); + +/* calculated current */ +static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, \ + ina2xx_show_value, NULL, INA2XX_CURRENT); + +/* calculated power */ +static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, \ + ina2xx_show_value, NULL, INA2XX_POWER); + +/* pointers to created device attributes */ +static struct attribute *ina2xx_attributes[] = { + &sensor_dev_attr_in0_input.dev_attr.attr, + &sensor_dev_attr_in1_input.dev_attr.attr, + &sensor_dev_attr_curr1_input.dev_attr.attr, + &sensor_dev_attr_power1_input.dev_attr.attr, + NULL, +}; + +static const struct attribute_group ina2xx_group = { + .attrs = ina2xx_attributes, +}; + +static int ina2xx_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adapter = client->adapter; + struct ina2xx_data *data; + struct ina2xx_platform_data *pdata; + int ret = 0; + long shunt = 10000; /* default shunt value 10mOhms */ + + 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; + + if (client->dev.platform_data) { + pdata = + (struct ina2xx_platform_data *)client->dev.platform_data; + shunt = pdata->shunt_uohms; + } + + if (shunt <= 0) + return -ENODEV; + + /* set the device type */ + data->kind = id->driver_data; + + switch (data->kind) { + case ina219: + /* device configuration */ + ina2xx_write_word(client, INA2XX_CONFIG, INA219_CONFIG_DEFAULT); + + /* set current LSB to 1mA, shunt is in uOhms */ + /* (equation 13 in datasheet) */ + ina2xx_write_word(client, INA2XX_CALIBRATION, 40960000 / shunt); + dev_info(&client->dev, + "power monitor INA219 (Rshunt = %li uOhm)\n", shunt); + data->registers = INA219_REGISTERS; + break; + case ina226: + /* device configuration */ + ina2xx_write_word(client, INA2XX_CONFIG, INA226_CONFIG_DEFAULT); + + /* set current LSB to 1mA, shunt is in uOhms */ + /* (equation 1 in datasheet)*/ + ina2xx_write_word(client, INA2XX_CALIBRATION, 5120000 / shunt); + dev_info(&client->dev, + "power monitor INA226 (Rshunt = %li uOhm)\n", shunt); + data->registers = INA226_REGISTERS; + break; + default: + /* unknown device id */ + return -ENODEV; + } + + i2c_set_clientdata(client, data); + mutex_init(&data->update_lock); + + ret = sysfs_create_group(&client->dev.kobj, &ina2xx_group); + if (ret) + return ret; + + data->hwmon_dev = hwmon_device_register(&client->dev); + if (IS_ERR(data->hwmon_dev)) { + ret = PTR_ERR(data->hwmon_dev); + goto out_err_hwmon; + } + + return 0; + +out_err_hwmon: + sysfs_remove_group(&client->dev.kobj, &ina2xx_group); + return ret; +} + +static int ina2xx_remove(struct i2c_client *client) +{ + struct ina2xx_data *data = i2c_get_clientdata(client); + + hwmon_device_unregister(data->hwmon_dev); + sysfs_remove_group(&client->dev.kobj, &ina2xx_group); + + return 0; +} + +static const struct i2c_device_id ina2xx_id[] = { + { "ina219", ina219 }, + { "ina226", ina226 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ina2xx_id); + +static struct i2c_driver ina2xx_driver = { + .driver = { + .name = "ina2xx", + }, + .probe = ina2xx_probe, + .remove = ina2xx_remove, + .id_table = ina2xx_id, +}; + +static int __init ina2xx_init(void) +{ + return i2c_add_driver(&ina2xx_driver); +} + +static void __exit ina2xx_exit(void) +{ + i2c_del_driver(&ina2xx_driver); +} + +MODULE_AUTHOR("Lothar Felten <l-felten@ti.com>"); +MODULE_DESCRIPTION("ina2xx driver"); +MODULE_LICENSE("GPL"); + +module_init(ina2xx_init); +module_exit(ina2xx_exit); diff --git a/include/linux/platform_data/ina2xx.h b/include/linux/platform_data/ina2xx.h new file mode 100644 index 000000000000..9abc0ca7259b --- /dev/null +++ b/include/linux/platform_data/ina2xx.h @@ -0,0 +1,19 @@ +/* + * Driver for Texas Instruments INA219, INA226 power monitor chips + * + * Copyright (C) 2012 Lothar Felten <l-felten@ti.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * For further information, see the Documentation/hwmon/ina2xx file. + */ + +/** + * struct ina2xx_platform_data - ina2xx info + * @shunt_uohms shunt resistance in microohms + */ +struct ina2xx_platform_data { + long shunt_uohms; +}; |
