path: root/Documentation/hwmon
diff options
authorIra Snyder <>2009-01-07 16:37:32 +0100
committerJean Delvare <>2009-01-07 16:37:32 +0100
commit6e34b187bc216fc632769fb8b906d3a29ccd8f14 (patch)
treeb0b05a1019c1ca884261e22c647416c6e82c4b06 /Documentation/hwmon
parent2f650631b3710622666367474b5475ff81ba486e (diff)
hwmon: Add LTC4245 driver
Add Linux support for the Linear Technology LTC4245 Multiple Supply Hot Swap controller I2C monitoring interface. Signed-off-by: Ira W. Snyder <> Acked-by: Hans de Goede <> Signed-off-by: Jean Delvare <>
Diffstat (limited to 'Documentation/hwmon')
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diff --git a/Documentation/hwmon/ltc4245 b/Documentation/hwmon/ltc4245
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+Kernel driver ltc4245
+Supported chips:
+ * Linear Technology LTC4245
+ Prefix: 'ltc4245'
+ Addresses scanned: 0x20-0x3f
+ Datasheet:
+Author: Ira W. Snyder <>
+The LTC4245 controller allows a board to be safely inserted and removed
+from a live backplane in multiple supply systems such as CompactPCI and
+PCI Express.
+Usage Notes
+This driver does not probe for LTC4245 devices, due to the fact that some
+of the possible addresses are unfriendly to probing. You will need to use
+the "force" parameter to tell the driver where to find the device.
+Example: the following will load the driver for an LTC4245 at address 0x23
+on I2C bus #1:
+$ modprobe ltc4245 force=1,0x23
+Sysfs entries
+The LTC4245 has built-in limits for over and under current warnings. This
+makes it very likely that the reference circuit will be used.
+This driver uses the values in the datasheet to change the register values
+into the values specified in the sysfs-interface document. The current readings
+rely on the sense resistors listed in Table 2: "Sense Resistor Values".
+in1_input 12v input voltage (mV)
+in2_input 5v input voltage (mV)
+in3_input 3v input voltage (mV)
+in4_input Vee (-12v) input voltage (mV)
+in1_min_alarm 12v input undervoltage alarm
+in2_min_alarm 5v input undervoltage alarm
+in3_min_alarm 3v input undervoltage alarm
+in4_min_alarm Vee (-12v) input undervoltage alarm
+curr1_input 12v current (mA)
+curr2_input 5v current (mA)
+curr3_input 3v current (mA)
+curr4_input Vee (-12v) current (mA)
+curr1_max_alarm 12v overcurrent alarm
+curr2_max_alarm 5v overcurrent alarm
+curr3_max_alarm 3v overcurrent alarm
+curr4_max_alarm Vee (-12v) overcurrent alarm
+in5_input 12v output voltage (mV)
+in6_input 5v output voltage (mV)
+in7_input 3v output voltage (mV)
+in8_input Vee (-12v) output voltage (mV)
+in5_min_alarm 12v output undervoltage alarm
+in6_min_alarm 5v output undervoltage alarm
+in7_min_alarm 3v output undervoltage alarm
+in8_min_alarm Vee (-12v) output undervoltage alarm
+in9_input GPIO #1 voltage data
+in10_input GPIO #2 voltage data
+in11_input GPIO #3 voltage data
+power1_input 12v power usage (mW)
+power2_input 5v power usage (mW)
+power3_input 3v power usage (mW)
+power4_input Vee (-12v) power usage (mW)