[PATCH 1/1] iio: adc: Add driver for the TI INA3221 Triple Current/Voltage Monitor

From: Andrew F. Davis
Date: Fri Apr 08 2016 - 14:20:34 EST

The INA3221 is a three-channel, high-side current and bus voltage monitor
with an I2C and SMBUS compatible interface.

Signed-off-by: Andrew F. Davis <afd@xxxxxx>
---
.../ABI/testing/sysfs-bus-iio-adc-ina3221 | 23 ++
drivers/iio/adc/Kconfig | 7 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/ina3221.c | 417 +++++++++++++++++++++
4 files changed, 448 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-adc-ina3221
create mode 100644 drivers/iio/adc/ina3221.c

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-ina3221 b/Documentation/ABI/testing/sysfs-bus-iio-adc-ina3221
new file mode 100644
index 0000000..bbe4f8c
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-iio-adc-ina3221
@@ -0,0 +1,23 @@
+What: /sys/bus/iio/devices/iio:deviceX/in_voltageY_shunt_(raw|scale)
+What: /sys/bus/iio/devices/iio:deviceX/in_voltageY_bus_(raw|scale)
+Date: April 2016
+KernelVersion: 4.7
+Contact: Andrew F. Davis <afd@xxxxxx>
+Description:
+ Shunt and Bus voltage for each channel.
+
+What: /sys/bus/iio/devices/iio:deviceX/shunt_integration_time[_available]
+What: /sys/bus/iio/devices/iio:deviceX/bus_integration_time[_available]
+Date: April 2016
+KernelVersion: 4.7
+Contact: Andrew F. Davis <afd@xxxxxx>
+Description:
+ Shunt and Bus integration time for each channel.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_voltageY_shunt_critical_(raw|scale)
+What: /sys/bus/iio/devices/iio:deviceX/in_voltageY_shunt_warning_(raw|scale)
+Date: April 2016
+KernelVersion: 4.7
+Contact: Andrew F. Davis <afd@xxxxxx>
+Description:
+ Shunt voltage critical and warning trigger levels.
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index af4aea7..d713c9c 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -232,6 +232,13 @@ config IMX7D_ADC
This driver can also be built as a module. If so, the module will be
called imx7d_adc.

+config INA3221
+ tristate "Texas Instruments INA3221 Triple Power Monitor"
+ depends on I2C
+ select REGMAP_I2C
+ help
+ Say yes here to build support for TI INA3221 Triple Power Monitor.
+
config LP8788_ADC
tristate "LP8788 ADC driver"
depends on MFD_LP8788
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 0cb7921..eebe0c6 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_FSL_MX25_ADC) += fsl-imx25-gcq.o
obj-$(CONFIG_HI8435) += hi8435.o
obj-$(CONFIG_IMX7D_ADC) += imx7d_adc.o
obj-$(CONFIG_INA2XX_ADC) += ina2xx-adc.o
+obj-$(CONFIG_INA3221) += ina3221.o
obj-$(CONFIG_LP8788_ADC) += lp8788_adc.o
obj-$(CONFIG_MAX1027) += max1027.o
obj-$(CONFIG_MAX1363) += max1363.o
diff --git a/drivers/iio/adc/ina3221.c b/drivers/iio/adc/ina3221.c
new file mode 100644
index 0000000..e5b9df97
--- /dev/null
+++ b/drivers/iio/adc/ina3221.c
@@ -0,0 +1,417 @@
+/*
+ * INA3221 Triple Current/Voltage Monitor
+ *
+ * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/
+ * Andrew F. Davis <afd@xxxxxx>
+ *
+ * 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.
+ *
+ * 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.
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define INA3221_DRIVER_NAME "ina3221"
+
+#define INA3221_CONFIG 0x00
+#define INA3221_SHUNT1 0x01
+#define INA3221_BUS1 0x02
+#define INA3221_SHUNT2 0x03
+#define INA3221_BUS2 0x04
+#define INA3221_SHUNT3 0x05
+#define INA3221_BUS3 0x06
+#define INA3221_CRIT1 0x07
+#define INA3221_WARN1 0x08
+#define INA3221_CRIT2 0x09
+#define INA3221_WARN2 0x0a
+#define INA3221_CRIT3 0x0b
+#define INA3221_WARN3 0x0c
+#define INA3221_SHUNT_SUM 0x0d
+#define INA3221_SHUNT_SUM_LIMIT 0x0e
+#define INA3221_MASK_ENABLE 0x0f
+#define INA3221_POWERV_HLIMIT 0x10
+#define INA3221_POWERV_LLIMIT 0x11
+
+#define INA3221_CONFIG_MODE_SHUNT BIT(1)
+#define INA3221_CONFIG_MODE_BUS BIT(2)
+#define INA3221_CONFIG_MODE_CONTINUOUS BIT(3)
+
+enum ina3221_fields {
+ /* Configuration */
+ F_MODE, F_SHUNT_CT, F_BUS_CT, F_AVG,
+ F_CHAN3_EN, F_CHAN2_EN, F_CHAN1_EN, F_RST,
+
+ /* sentinel */
+ F_MAX_FIELDS
+};
+
+static const struct reg_field ina3221_reg_fields[] = {
+ [F_MODE] = REG_FIELD(INA3221_CONFIG, 0, 2),
+ [F_SHUNT_CT] = REG_FIELD(INA3221_CONFIG, 3, 5),
+ [F_BUS_CT] = REG_FIELD(INA3221_CONFIG, 6, 8),
+ [F_AVG] = REG_FIELD(INA3221_CONFIG, 9, 11),
+ [F_CHAN3_EN] = REG_FIELD(INA3221_CONFIG, 12, 12),
+ [F_CHAN2_EN] = REG_FIELD(INA3221_CONFIG, 13, 13),
+ [F_CHAN1_EN] = REG_FIELD(INA3221_CONFIG, 14, 14),
+ [F_RST] = REG_FIELD(INA3221_CONFIG, 15, 15),
+};
+
+#define is_bus_reg(_reg) \
+ (_reg == INA3221_BUS1 || \
+ _reg == INA3221_BUS2 || \
+ _reg == INA3221_BUS3)
+
+/**
+ * struct ina3221_data - device specific information
+ * @dev: Device structure
+ * @regmap: Register map of the device
+ * @fields: Register fields of the device
+ */
+struct ina3221_data {
+ struct device *dev;
+ struct regmap *regmap;
+ struct regmap_field *fields[F_MAX_FIELDS];
+};
+
+/**
+ * struct ina3221_reg_lookup - value element in iio lookup table map
+ * @integer: Integer component of value
+ * @fract: Fractional component of value
+ */
+struct ina3221_reg_lookup {
+ int integer;
+ int fract;
+};
+
+static const struct ina3221_reg_lookup ina3221_conv_time_table[] = {
+ {.fract = 140}, {.fract = 204}, {.fract = 332}, {.fract = 588},
+ {.fract = 1100}, {.fract = 2116}, {.fract = 4156}, {.fract = 8244},
+};
+
+static const int ina3221_avg_table[] = { 1, 4, 16, 64, 128, 256, 512, 1024 };
+static IIO_CONST_ATTR(oversampling_ratio_available, "1 4 16 64 128 256 512 1024");
+
+static int ina3221_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct ina3221_data *ina = iio_priv(indio_dev);
+ unsigned int regval;
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = regmap_read(ina->regmap, chan->address, &regval);
+ if (ret)
+ return ret;
+
+ *val = (s16)sign_extend32(regval >> 3, 12);
+
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_SCALE:
+ if (is_bus_reg(chan->address)) {
+ *val = 8;
+ *val2 = 0;
+ } else {
+ *val = 0;
+ *val2 = 40000;
+ }
+
+ return IIO_VAL_INT_PLUS_MICRO;
+
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ ret = regmap_field_read(ina->fields[F_AVG], &regval);
+ if (ret)
+ return ret;
+
+ *val = ina3221_avg_table[regval];
+
+ return IIO_VAL_INT;
+ }
+
+ return -EINVAL;
+}
+
+static int ina3221_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct ina3221_data *ina = iio_priv(indio_dev);
+ int i;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ return regmap_write(ina->regmap, chan->address, val << 3);
+
+ case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+ if (val2)
+ return -EINVAL;
+ for (i = 0; i < ARRAY_SIZE(ina3221_avg_table); i++)
+ if (ina3221_avg_table[i] == val)
+ break;
+ if (i == ARRAY_SIZE(ina3221_avg_table))
+ return -EINVAL;
+
+ return regmap_field_write(ina->fields[F_AVG], i);
+ }
+
+ return -EINVAL;
+}
+
+#define INA3221_CHAN(_channel, _address, _name) { \
+ .type = IIO_VOLTAGE, \
+ .channel = (_channel), \
+ .address = (_address), \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
+ .extend_name = _name, \
+ .indexed = true, \
+}
+
+static const struct iio_chan_spec ina3221_channels[] = {
+ INA3221_CHAN(1, INA3221_SHUNT1, "shunt"),
+ INA3221_CHAN(1, INA3221_BUS1, "bus"),
+ INA3221_CHAN(1, INA3221_CRIT1, "shunt_critical"),
+ INA3221_CHAN(1, INA3221_WARN1, "shunt_warning"),
+
+ INA3221_CHAN(2, INA3221_SHUNT2, "shunt"),
+ INA3221_CHAN(2, INA3221_BUS2, "bus"),
+ INA3221_CHAN(2, INA3221_CRIT2, "shunt_critical"),
+ INA3221_CHAN(2, INA3221_WARN2, "shunt_warning"),
+
+ INA3221_CHAN(3, INA3221_SHUNT3, "shunt"),
+ INA3221_CHAN(3, INA3221_BUS3, "bus"),
+ INA3221_CHAN(3, INA3221_CRIT3, "shunt_critical"),
+ INA3221_CHAN(3, INA3221_WARN3, "shunt_warning"),
+};
+
+struct ina3221_attr {
+ struct device_attribute dev_attr;
+ struct device_attribute dev_attr_available;
+ unsigned int field;
+ const struct ina3221_reg_lookup *table;
+ unsigned int table_size;
+};
+
+#define to_ina3221_attr(_dev_attr) \
+ container_of(_dev_attr, struct ina3221_attr, dev_attr)
+
+#define to_ina3221_attr_available(_dev_attr) \
+ container_of(_dev_attr, struct ina3221_attr, dev_attr_available)
+
+static ssize_t ina3221_show_register(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct ina3221_data *ina = iio_priv(indio_dev);
+ struct ina3221_attr *ina3221_attr = to_ina3221_attr(attr);
+ unsigned int reg_val;
+ int vals[2];
+ int ret;
+
+ ret = regmap_field_read(ina->fields[ina3221_attr->field], &reg_val);
+ if (ret)
+ return ret;
+
+ vals[0] = ina3221_attr->table[reg_val].integer;
+ vals[1] = ina3221_attr->table[reg_val].fract;
+
+ return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
+}
+
+static ssize_t ina3221_store_register(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct ina3221_data *ina = iio_priv(indio_dev);
+ struct ina3221_attr *ina3221_attr = to_ina3221_attr(attr);
+ long val;
+ int integer, fract, ret;
+
+ ret = iio_str_to_fixpoint(buf, 100000, &integer, &fract);
+ if (ret)
+ return ret;
+
+ if (integer < 0)
+ return -EINVAL;
+
+ for (val = 0; val < ina3221_attr->table_size; val++)
+ if (ina3221_attr->table[val].integer == integer &&
+ ina3221_attr->table[val].fract == fract) {
+ ret = regmap_field_write(ina->fields[ina3221_attr->field], val);
+ if (ret)
+ return ret;
+
+ return count;
+ }
+
+ return -EINVAL;
+}
+
+static ssize_t ina3221_show_available(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ina3221_attr *ina3221_attr = to_ina3221_attr_available(attr);
+ ssize_t len = 0;
+ int i;
+
+ for (i = 0; i < ina3221_attr->table_size; i++)
+ len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06u ",
+ ina3221_attr->table[i].integer,
+ ina3221_attr->table[i].fract);
+
+ if (len > 0)
+ buf[len - 1] = '\n';
+
+ return len;
+}
+
+#define INA3221_ATTR(_name, _field, _table) \
+ struct ina3221_attr ina3221_attr_##_name = { \
+ .dev_attr = __ATTR(_name, (S_IRUGO | S_IWUSR), \
+ ina3221_show_register, \
+ ina3221_store_register), \
+ .dev_attr_available = __ATTR(_name##_available, S_IRUGO, \
+ ina3221_show_available, NULL), \
+ .field = _field, \
+ .table = _table, \
+ .table_size = ARRAY_SIZE(_table), \
+ }
+
+static INA3221_ATTR(shunt_integration_time, F_SHUNT_CT, ina3221_conv_time_table);
+static INA3221_ATTR(bus_integration_time, F_BUS_CT, ina3221_conv_time_table);
+
+static struct attribute *ina3221_attributes[] = {
+ &ina3221_attr_shunt_integration_time.dev_attr.attr,
+ &ina3221_attr_shunt_integration_time.dev_attr_available.attr,
+ &ina3221_attr_bus_integration_time.dev_attr.attr,
+ &ina3221_attr_bus_integration_time.dev_attr_available.attr,
+ &iio_const_attr_oversampling_ratio_available.dev_attr.attr,
+ NULL,
+};
+
+static const struct attribute_group ina3221_attribute_group = {
+ .attrs = ina3221_attributes,
+};
+
+static const struct iio_info ina3221_iio_info = {
+ .driver_module = THIS_MODULE,
+ .attrs = &ina3221_attribute_group,
+ .read_raw = ina3221_read_raw,
+ .write_raw = ina3221_write_raw,
+};
+
+static const struct regmap_range ina3221_yes_ranges[] = {
+ regmap_reg_range(INA3221_SHUNT1, INA3221_BUS3),
+ regmap_reg_range(INA3221_MASK_ENABLE, INA3221_MASK_ENABLE),
+};
+
+static const struct regmap_access_table ina3221_volatile_table = {
+ .yes_ranges = ina3221_yes_ranges,
+ .n_yes_ranges = ARRAY_SIZE(ina3221_yes_ranges),
+};
+
+static const struct regmap_config ina3221_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 16,
+
+ .cache_type = REGCACHE_RBTREE,
+ .volatile_table = &ina3221_volatile_table,
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id ina3221_of_match[] = {
+ { .compatible = "ti,ina3221", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ina3221_of_match);
+#endif
+
+static int ina3221_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct iio_dev *indio_dev;
+ struct ina3221_data *ina;
+ int i, ret;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*ina));
+ if (!indio_dev)
+ return -ENOMEM;
+ i2c_set_clientdata(client, indio_dev);
+
+ ina = iio_priv(indio_dev);
+
+ ina->dev = &client->dev;
+
+ ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config);
+ if (IS_ERR(ina->regmap)) {
+ dev_err(ina->dev, "Unable to allocate register map\n");
+ return PTR_ERR(ina->regmap);
+ }
+
+ for (i = 0; i < F_MAX_FIELDS; i++) {
+ ina->fields[i] = devm_regmap_field_alloc(ina->dev,
+ ina->regmap,
+ ina3221_reg_fields[i]);
+ if (IS_ERR(ina->fields[i])) {
+ dev_err(ina->dev, "Unable to allocate regmap fields\n");
+ return PTR_ERR(ina->fields[i]);
+ }
+ }
+
+ ret = regmap_field_write(ina->fields[F_RST], true);
+ if (ret) {
+ dev_err(ina->dev, "Unable to reset device\n");
+ return ret;
+ }
+
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->dev.parent = ina->dev;
+ indio_dev->channels = ina3221_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ina3221_channels);
+ indio_dev->name = INA3221_DRIVER_NAME;
+ indio_dev->info = &ina3221_iio_info;
+
+ ret = devm_iio_device_register(ina->dev, indio_dev);
+ if (ret) {
+ dev_err(ina->dev, "Unable to register IIO device\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct i2c_device_id ina3221_ids[] = {
+ { "ina3221", 0 },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, ina3221_ids);
+
+static struct i2c_driver ina3221_i2c_driver = {
+ .driver = {
+ .name = INA3221_DRIVER_NAME,
+ .of_match_table = of_match_ptr(ina3221_of_match),
+ },
+ .probe = ina3221_probe,
+ .id_table = ina3221_ids,
+};
+module_i2c_driver(ina3221_i2c_driver);
+
+MODULE_AUTHOR("Andrew F. Davis <afd@xxxxxx>");
+MODULE_DESCRIPTION("Texas Instruments INA3221 Driver");
+MODULE_LICENSE("GPL v2");
--
2.8.1