diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/hwmon/ltc4261 | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/Documentation/hwmon/ltc4261')
-rw-r--r-- | kernel/Documentation/hwmon/ltc4261 | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/kernel/Documentation/hwmon/ltc4261 b/kernel/Documentation/hwmon/ltc4261 new file mode 100644 index 000000000..9378a75c6 --- /dev/null +++ b/kernel/Documentation/hwmon/ltc4261 @@ -0,0 +1,63 @@ +Kernel driver ltc4261 +===================== + +Supported chips: + * Linear Technology LTC4261 + Prefix: 'ltc4261' + Addresses scanned: - + Datasheet: + http://cds.linear.com/docs/Datasheet/42612fb.pdf + +Author: Guenter Roeck <linux@roeck-us.net> + + +Description +----------- + +The LTC4261/LTC4261-2 negative voltage Hot Swap controllers allow a board +to be safely inserted and removed from a live backplane. + + +Usage Notes +----------- + +This driver does not probe for LTC4261 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 LTC4261 at address 0x10 +on I2C bus #1: +$ modprobe ltc4261 +$ echo ltc4261 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. + +The chip has two voltage sensors, but only one set of voltage alarm status bits. +In many many designs, those alarms are associated with the ADIN2 sensor, due to +the proximity of the ADIN2 pin to the OV pin. ADIN2 is, however, not available +on all chip variants. To ensure that the alarm condition is reported to the user, +report it with both voltage sensors. + +in1_input ADIN2 voltage (mV) +in1_min_alarm ADIN/ADIN2 Undervoltage alarm +in1_max_alarm ADIN/ADIN2 Overvoltage alarm + +in2_input ADIN voltage (mV) +in2_min_alarm ADIN/ADIN2 Undervoltage alarm +in2_max_alarm ADIN/ADIN2 Overvoltage alarm + +curr1_input SENSE current (mA) +curr1_alarm SENSE overcurrent alarm |