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authorGuenter Roeck <linux@roeck-us.net>2014-01-11 00:17:05 -0800
committerGuenter Roeck <linux@roeck-us.net>2014-03-03 08:01:03 -0800
commit69e1ded651ee31c8a570d58647902a55806d0db8 (patch)
tree26afb63215698900a51901807b66de66028e08f4 /Documentation/hwmon
parent79ffe8594f23475d83112cd5bd68805f91e49170 (diff)
downloadlinux-69e1ded651ee31c8a570d58647902a55806d0db8.tar.bz2
hwmon: Driver for Linear Technologies LTC4260
LTC4260 is a Positive Voltage Hot Swap Controller. The driver currently only supports voltage monitoring, not voltage control. Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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+Kernel driver ltc4260
+=====================
+
+Supported chips:
+ * Linear Technology LTC4260
+ Prefix: 'ltc4260'
+ Addresses scanned: -
+ Datasheet:
+ http://cds.linear.com/docs/en/datasheet/4260fc.pdf
+
+Author: Guenter Roeck <linux@roeck-us.net>
+
+
+Description
+-----------
+
+The LTC4260 Hot Swap controller allows a board to be safely inserted
+and removed from a live backplane.
+
+
+Usage Notes
+-----------
+
+This driver does not probe for LTC4260 devices, since there is no register
+which can be safely used to identify the chip. You will have to instantiate
+the devices explicitly.
+
+Example: the following will load the driver for an LTC4260 at address 0x10
+on I2C bus #1:
+$ modprobe ltc4260
+$ echo ltc4260 0x10 > /sys/bus/i2c/devices/i2c-1/new_device
+
+
+Sysfs entries
+-------------
+
+Voltage readings provided by this driver are reported as obtained from the ADC
+registers. If a set of voltage divider resistors is installed, calculate the
+real voltage by multiplying the reported value with (R1+R2)/R2, where R1 is the
+value of the divider resistor against the measured voltage and R2 is the value
+of the divider resistor against Ground.
+
+Current reading provided by this driver is reported as obtained from the ADC
+Current Sense register. The reported value assumes that a 1 mOhm sense resistor
+is installed. If a different sense resistor is installed, calculate the real
+current by dividing the reported value by the sense resistor value in mOhm.
+
+in1_input SOURCE voltage (mV)
+in1_min_alarm Undervoltage alarm
+in1_max_alarm Overvoltage alarm
+
+in2_input ADIN voltage (mV)
+in2_alarm Power bad alarm
+
+curr1_input SENSE current (mA)
+curr1_alarm SENSE overcurrent alarm