aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/hwmon/ltc2990.rst
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/hwmon/ltc2990.rst')
-rw-r--r--Documentation/hwmon/ltc2990.rst62
1 files changed, 62 insertions, 0 deletions
diff --git a/Documentation/hwmon/ltc2990.rst b/Documentation/hwmon/ltc2990.rst
new file mode 100644
index 000000000000..e0a369e679d3
--- /dev/null
+++ b/Documentation/hwmon/ltc2990.rst
@@ -0,0 +1,62 @@
+Kernel driver ltc2990
+=====================
+
+
+Supported chips:
+
+ * Linear Technology LTC2990
+
+ Prefix: 'ltc2990'
+
+ Addresses scanned: -
+
+ Datasheet: http://www.linear.com/product/ltc2990
+
+
+
+Author:
+
+ - Mike Looijmans <mike.looijmans@topic.nl>
+ - Tom Levens <tom.levens@cern.ch>
+
+
+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 with an external
+diode.
+
+
+Usage Notes
+-----------
+
+This driver does not probe for PMBus devices. You will have to instantiate
+devices explicitly.
+
+
+Sysfs attributes
+----------------
+
+============= ==================================================
+in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V)
+temp1_input Internal chip temperature in millidegrees Celsius
+============= ==================================================
+
+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 Celsius
+temp3_input External temperature sensor TR2 in millidegrees Celsius
+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.