#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/property.h>
#define LTC2990_STATUS 0x00
#define LTC2990_CONTROL 0x01
#define LTC2990_TRIGGER 0x02
#define LTC2990_TINT_MSB 0x04
#define LTC2990_V1_MSB 0x06
#define LTC2990_V2_MSB 0x08
#define LTC2990_V3_MSB 0x0A
#define LTC2990_V4_MSB 0x0C
#define LTC2990_VCC_MSB 0x0E
#define LTC2990_IN0 BIT(0)
#define LTC2990_IN1 BIT(1)
#define LTC2990_IN2 BIT(2)
#define LTC2990_IN3 BIT(3)
#define LTC2990_IN4 BIT(4)
#define LTC2990_CURR1 BIT(5)
#define LTC2990_CURR2 BIT(6)
#define LTC2990_TEMP1 BIT(7)
#define LTC2990_TEMP2 BIT(8)
#define LTC2990_TEMP3 BIT(9)
#define LTC2990_NONE 0
#define LTC2990_ALL GENMASK(9, 0)
#define LTC2990_MODE0_SHIFT 0
#define LTC2990_MODE0_MASK GENMASK(2, 0)
#define LTC2990_MODE1_SHIFT 3
#define LTC2990_MODE1_MASK GENMASK(1, 0)
static const int ltc2990_attrs_ena_0[] = {
LTC2990_IN1 | LTC2990_IN2 | LTC2990_TEMP3,
LTC2990_CURR1 | LTC2990_TEMP3,
LTC2990_CURR1 | LTC2990_IN3 | LTC2990_IN4,
LTC2990_TEMP2 | LTC2990_IN3 | LTC2990_IN4,
LTC2990_TEMP2 | LTC2990_CURR2,
LTC2990_TEMP2 | LTC2990_TEMP3,
LTC2990_CURR1 | LTC2990_CURR2,
LTC2990_IN1 | LTC2990_IN2 | LTC2990_IN3 | LTC2990_IN4
};
static const int ltc2990_attrs_ena_1[] = {
LTC2990_NONE,
LTC2990_TEMP2 | LTC2990_IN1 | LTC2990_CURR1,
LTC2990_TEMP3 | LTC2990_IN3 | LTC2990_CURR2,
LTC2990_ALL
};
struct ltc2990_data {
struct i2c_client *i2c;
u32 mode[2];
};
static int ltc2990_get_value(struct i2c_client *i2c, int index, int *result)
{
int val;
u8 reg;
switch (index) {
case LTC2990_IN0:
reg = LTC2990_VCC_MSB;
break;
case LTC2990_IN1:
case LTC2990_CURR1:
case LTC2990_TEMP2:
reg = LTC2990_V1_MSB;
break;
case LTC2990_IN2:
reg = LTC2990_V2_MSB;
break;
case LTC2990_IN3:
case LTC2990_CURR2:
case LTC2990_TEMP3:
reg = LTC2990_V3_MSB;
break;
case LTC2990_IN4:
reg = LTC2990_V4_MSB;
break;
case LTC2990_TEMP1:
reg = LTC2990_TINT_MSB;
break;
default:
return -EINVAL;
}
val = i2c_smbus_read_word_swapped(i2c, reg);
if (unlikely(val < 0))
return val;
switch (index) {
case LTC2990_TEMP1:
case LTC2990_TEMP2:
case LTC2990_TEMP3:
*result = sign_extend32(val, 12) * 1000 / 16;
break;
case LTC2990_CURR1:
case LTC2990_CURR2:
*result = sign_extend32(val, 14) * 1942 / 100;
break;
case LTC2990_IN0:
*result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
break;
case LTC2990_IN1:
case LTC2990_IN2:
case LTC2990_IN3:
case LTC2990_IN4:
*result = sign_extend32(val, 14) * 30518 / (100 * 1000);
break;
default:
return -EINVAL;
}
return 0;
}
static ssize_t ltc2990_value_show(struct device *dev,
struct device_attribute *da, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct ltc2990_data *data = dev_get_drvdata(dev);
int value;
int ret;
ret = ltc2990_get_value(data->i2c, attr->index, &value);
if (unlikely(ret < 0))
return ret;
return sysfs_emit(buf, "%d\n", value);
}
static umode_t ltc2990_attrs_visible(struct kobject *kobj,
struct attribute *a, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct ltc2990_data *data = dev_get_drvdata(dev);
struct device_attribute *da =
container_of(a, struct device_attribute, attr);
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 |
(ltc2990_attrs_ena_0[data->mode[0]] &
ltc2990_attrs_ena_1[data->mode[1]]);
if (attr->index & attrs_mask)
return a->mode;
return 0;
}
static SENSOR_DEVICE_ATTR_RO(temp1_input, ltc2990_value, LTC2990_TEMP1);
static SENSOR_DEVICE_ATTR_RO(temp2_input, ltc2990_value, LTC2990_TEMP2);
static SENSOR_DEVICE_ATTR_RO(temp3_input, ltc2990_value, LTC2990_TEMP3);
static SENSOR_DEVICE_ATTR_RO(curr1_input, ltc2990_value, LTC2990_CURR1);
static SENSOR_DEVICE_ATTR_RO(curr2_input, ltc2990_value, LTC2990_CURR2);
static SENSOR_DEVICE_ATTR_RO(in0_input, ltc2990_value, LTC2990_IN0);
static SENSOR_DEVICE_ATTR_RO(in1_input, ltc2990_value, LTC2990_IN1);
static SENSOR_DEVICE_ATTR_RO(in2_input, ltc2990_value, LTC2990_IN2);
static SENSOR_DEVICE_ATTR_RO(in3_input, ltc2990_value, LTC2990_IN3);
static SENSOR_DEVICE_ATTR_RO(in4_input, ltc2990_value, LTC2990_IN4);
static struct attribute *ltc2990_attrs[] = {
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp2_input.dev_attr.attr,
&sensor_dev_attr_temp3_input.dev_attr.attr,
&sensor_dev_attr_curr1_input.dev_attr.attr,
&sensor_dev_attr_curr2_input.dev_attr.attr,
&sensor_dev_attr_in0_input.dev_attr.attr,
&sensor_dev_attr_in1_input.dev_attr.attr,
&sensor_dev_attr_in2_input.dev_attr.attr,
&sensor_dev_attr_in3_input.dev_attr.attr,
&sensor_dev_attr_in4_input.dev_attr.attr,
NULL,
};
static const struct attribute_group ltc2990_group = {
.attrs = ltc2990_attrs,
.is_visible = ltc2990_attrs_visible,
};
__ATTRIBUTE_GROUPS(ltc2990);
static int ltc2990_i2c_probe(struct i2c_client *i2c)
{
int ret;
struct device *hwmon_dev;
struct ltc2990_data *data;
if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA))
return -ENODEV;
data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), GFP_KERNEL);
if (unlikely(!data))
return -ENOMEM;
data->i2c = i2c;
if (dev_fwnode(&i2c->dev)) {
ret = device_property_read_u32_array(&i2c->dev,
"lltc,meas-mode",
data->mode, 2);
if (ret < 0)
return ret;
if (data->mode[0] & ~LTC2990_MODE0_MASK ||
data->mode[1] & ~LTC2990_MODE1_MASK)
return -EINVAL;
} else {
ret = i2c_smbus_read_byte_data(i2c, LTC2990_CONTROL);
if (ret < 0)
return ret;
data->mode[0] = ret >> LTC2990_MODE0_SHIFT & LTC2990_MODE0_MASK;
data->mode[1] = ret >> LTC2990_MODE1_SHIFT & LTC2990_MODE1_MASK;
}
ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL,
data->mode[0] << LTC2990_MODE0_SHIFT |
data->mode[1] << LTC2990_MODE1_SHIFT);
if (ret < 0) {
dev_err(&i2c->dev, "Error: Failed to set control mode.\n");
return ret;
}
ret = i2c_smbus_write_byte_data(i2c, LTC2990_TRIGGER, 1);
if (ret < 0) {
dev_err(&i2c->dev, "Error: Failed to start acquisition.\n");
return ret;
}
hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev,
i2c->name,
data,
ltc2990_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct i2c_device_id ltc2990_i2c_id[] = {
{ "ltc2990" },
{}
};
MODULE_DEVICE_TABLE(i2c, ltc2990_i2c_id);
static struct i2c_driver ltc2990_i2c_driver = {
.driver = {
.name = "ltc2990",
},
.probe = ltc2990_i2c_probe,
.id_table = ltc2990_i2c_id,
};
module_i2c_driver(ltc2990_i2c_driver);
MODULE_DESCRIPTION("LTC2990 Sensor Driver");
MODULE_AUTHOR("Topic Embedded Products");
MODULE_LICENSE("GPL v2");
