cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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ltc4261.rst (2261B)


      1Kernel driver ltc4261
      2=====================
      3
      4Supported chips:
      5
      6  * Linear Technology LTC4261
      7
      8    Prefix: 'ltc4261'
      9
     10    Addresses scanned: -
     11
     12    Datasheet:
     13
     14	http://cds.linear.com/docs/Datasheet/42612fb.pdf
     15
     16Author: Guenter Roeck <linux@roeck-us.net>
     17
     18
     19Description
     20-----------
     21
     22The LTC4261/LTC4261-2 negative voltage Hot Swap controllers allow a board
     23to be safely inserted and removed from a live backplane.
     24
     25
     26Usage Notes
     27-----------
     28
     29This driver does not probe for LTC4261 devices, since there is no register
     30which can be safely used to identify the chip. You will have to instantiate
     31the devices explicitly.
     32
     33Example: the following will load the driver for an LTC4261 at address 0x10
     34on I2C bus #1::
     35
     36	$ modprobe ltc4261
     37	$ echo ltc4261 0x10 > /sys/bus/i2c/devices/i2c-1/new_device
     38
     39
     40Sysfs entries
     41-------------
     42
     43Voltage readings provided by this driver are reported as obtained from the ADC
     44registers. If a set of voltage divider resistors is installed, calculate the
     45real voltage by multiplying the reported value with (R1+R2)/R2, where R1 is the
     46value of the divider resistor against the measured voltage and R2 is the value
     47of the divider resistor against Ground.
     48
     49Current reading provided by this driver is reported as obtained from the ADC
     50Current Sense register. The reported value assumes that a 1 mOhm sense resistor
     51is installed. If a different sense resistor is installed, calculate the real
     52current by dividing the reported value by the sense resistor value in mOhm.
     53
     54The chip has two voltage sensors, but only one set of voltage alarm status bits.
     55In many many designs, those alarms are associated with the ADIN2 sensor, due to
     56the proximity of the ADIN2 pin to the OV pin. ADIN2 is, however, not available
     57on all chip variants. To ensure that the alarm condition is reported to the user,
     58report it with both voltage sensors.
     59
     60======================= =============================
     61in1_input		ADIN2 voltage (mV)
     62in1_min_alarm		ADIN/ADIN2 Undervoltage alarm
     63in1_max_alarm		ADIN/ADIN2 Overvoltage alarm
     64
     65in2_input		ADIN voltage (mV)
     66in2_min_alarm		ADIN/ADIN2 Undervoltage alarm
     67in2_max_alarm		ADIN/ADIN2 Overvoltage alarm
     68
     69curr1_input		SENSE current (mA)
     70curr1_alarm		SENSE overcurrent alarm
     71======================= =============================