aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--Documentation/hwmon/ltc299024
-rw-r--r--drivers/hwmon/Kconfig7
-rw-r--r--drivers/hwmon/ltc2990.c196
3 files changed, 185 insertions, 42 deletions
diff --git a/Documentation/hwmon/ltc2990 b/Documentation/hwmon/ltc2990
index c25211e90bdc..3ed68f676c0f 100644
--- a/Documentation/hwmon/ltc2990
+++ b/Documentation/hwmon/ltc2990
@@ -8,6 +8,7 @@ Supported chips:
Datasheet: http://www.linear.com/product/ltc2990
Author: Mike Looijmans <mike.looijmans@topic.nl>
+ Tom Levens <tom.levens@cern.ch>
Description
@@ -16,10 +17,8 @@ Description
LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor.
The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4)
can be combined to measure a differential voltage, which is typically used to
-measure current through a series resistor, or a temperature.
-
-This driver currently uses the 2x differential mode only. In order to support
-other modes, the driver will need to be expanded.
+measure current through a series resistor, or a temperature with an external
+diode.
Usage Notes
@@ -32,12 +31,19 @@ devices explicitly.
Sysfs attributes
----------------
+in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V)
+temp1_input Internal chip temperature in millidegrees Celcius
+
+A subset of the following attributes are visible, depending on the measurement
+mode of the chip.
+
+in[1-4]_input Voltage at V[1-4] pin in millivolt
+temp2_input External temperature sensor TR1 in millidegrees Celcius
+temp3_input External temperature sensor TR2 in millidegrees Celcius
+curr1_input Current in mA across V1-V2 assuming a 1mOhm sense resistor
+curr2_input Current in mA across V3-V4 assuming a 1mOhm sense resistor
+
The "curr*_input" measurements actually report the voltage drop across the
input pins in microvolts. This is equivalent to the current through a 1mOhm
sense resistor. Divide the reported value by the actual sense resistor value
in mOhm to get the actual value.
-
-in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V)
-temp1_input Internal chip temperature in millidegrees Celcius
-curr1_input Current in mA across v1-v2 assuming a 1mOhm sense resistor.
-curr2_input Current in mA across v3-v4 assuming a 1mOhm sense resistor.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 6ec307c93ece..f10840ad465c 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -717,15 +717,12 @@ config SENSORS_LTC2945
be called ltc2945.
config SENSORS_LTC2990
- tristate "Linear Technology LTC2990 (current monitoring mode only)"
+ tristate "Linear Technology LTC2990"
depends on I2C
help
If you say yes here you get support for Linear Technology LTC2990
I2C System Monitor. The LTC2990 supports a combination of voltage,
- current and temperature monitoring, but in addition to the Vcc supply
- voltage and chip temperature, this driver currently only supports
- reading two currents by measuring two differential voltages across
- series resistors.
+ current and temperature monitoring.
This driver can also be built as a module. If so, the module will
be called ltc2990.
diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c
index e320d212ac27..2aefdc58b242 100644
--- a/drivers/hwmon/ltc2990.c
+++ b/drivers/hwmon/ltc2990.c
@@ -5,10 +5,6 @@
* Author: Mike Looijmans <mike.looijmans@topic.nl>
*
* License: GPLv2
- *
- * This driver assumes the chip is wired as a dual current monitor, and
- * reports the voltage drop across two series resistors. It also reports
- * the chip's internal temperature and Vcc power supply voltage.
*/
#include <linux/bitops.h>
@@ -18,6 +14,7 @@
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/of.h>
#define LTC2990_STATUS 0x00
#define LTC2990_CONTROL 0x01
@@ -29,35 +26,109 @@
#define LTC2990_V4_MSB 0x0C
#define LTC2990_VCC_MSB 0x0E
-#define LTC2990_CONTROL_KELVIN BIT(7)
-#define LTC2990_CONTROL_SINGLE BIT(6)
-#define LTC2990_CONTROL_MEASURE_ALL (0x3 << 3)
-#define LTC2990_CONTROL_MODE_CURRENT 0x06
-#define LTC2990_CONTROL_MODE_VOLTAGE 0x07
+#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)
+
+/* Enabled measurements for mode bits 2..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
+};
+
+/* Enabled measurements for mode bits 4..3 */
+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];
+};
/* Return the converted value from the given register in uV or mC */
-static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result)
+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 (reg) {
- case LTC2990_TINT_MSB:
- /* internal temp, 0.0625 degrees/LSB, 13-bit */
+ switch (index) {
+ case LTC2990_TEMP1:
+ case LTC2990_TEMP2:
+ case LTC2990_TEMP3:
+ /* temp, 0.0625 degrees/LSB */
*result = sign_extend32(val, 12) * 1000 / 16;
break;
- case LTC2990_V1_MSB:
- case LTC2990_V3_MSB:
- /* Vx-Vy, 19.42uV/LSB. Depends on mode. */
+ case LTC2990_CURR1:
+ case LTC2990_CURR2:
+ /* Vx-Vy, 19.42uV/LSB */
*result = sign_extend32(val, 14) * 1942 / 100;
break;
- case LTC2990_VCC_MSB:
- /* Vcc, 305.18μV/LSB, 2.5V offset */
+ case LTC2990_IN0:
+ /* Vcc, 305.18uV/LSB, 2.5V offset */
*result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
break;
+ case LTC2990_IN1:
+ case LTC2990_IN2:
+ case LTC2990_IN3:
+ case LTC2990_IN4:
+ /* Vx, 305.18uV/LSB */
+ *result = sign_extend32(val, 14) * 30518 / (100 * 1000);
+ break;
default:
return -EINVAL; /* won't happen, keep compiler happy */
}
@@ -69,48 +140,117 @@ static ssize_t ltc2990_show_value(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(dev_get_drvdata(dev), attr->index, &value);
+ ret = ltc2990_get_value(data->i2c, attr->index, &value);
if (unlikely(ret < 0))
return ret;
return snprintf(buf, PAGE_SIZE, "%d\n", value);
}
+static umode_t ltc2990_attrs_visible(struct kobject *kobj,
+ struct attribute *a, int n)
+{
+ struct device *dev = container_of(kobj, struct device, 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(temp1_input, S_IRUGO, ltc2990_show_value, NULL,
- LTC2990_TINT_MSB);
+ LTC2990_TEMP1);
+static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, ltc2990_show_value, NULL,
+ LTC2990_TEMP2);
+static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, ltc2990_show_value, NULL,
+ LTC2990_TEMP3);
static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ltc2990_show_value, NULL,
- LTC2990_V1_MSB);
+ LTC2990_CURR1);
static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO, ltc2990_show_value, NULL,
- LTC2990_V3_MSB);
+ LTC2990_CURR2);
static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ltc2990_show_value, NULL,
- LTC2990_VCC_MSB);
+ LTC2990_IN0);
+static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ltc2990_show_value, NULL,
+ LTC2990_IN1);
+static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ltc2990_show_value, NULL,
+ LTC2990_IN2);
+static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ltc2990_show_value, NULL,
+ LTC2990_IN3);
+static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ltc2990_show_value, NULL,
+ 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,
};
-ATTRIBUTE_GROUPS(ltc2990);
+
+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,
const struct i2c_device_id *id)
{
int ret;
struct device *hwmon_dev;
+ struct ltc2990_data *data;
+ struct device_node *of_node = i2c->dev.of_node;
if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA))
return -ENODEV;
- /* Setup continuous mode, current monitor */
+ data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), GFP_KERNEL);
+ if (unlikely(!data))
+ return -ENOMEM;
+
+ data->i2c = i2c;
+
+ if (of_node) {
+ ret = of_property_read_u32_array(of_node, "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;
+ }
+
+ /* Setup continuous mode */
ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL,
- LTC2990_CONTROL_MEASURE_ALL |
- LTC2990_CONTROL_MODE_CURRENT);
+ 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;
@@ -124,7 +264,7 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c,
hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev,
i2c->name,
- i2c,
+ data,
ltc2990_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.