android_kernel_motorola_sm6225/Documentation/hwmon/ltc4215
Ira Snyder 72f5de92e1 hwmon: Add LTC4215 driver
Add Linux support for the Linear Technology LTC4215 Hot Swap controller
I2C monitoring interface.

I have tested the driver with my board, and it appears to work fine.  With
the power supplies disabled, it reads 11.93V input, 1.93V output, no
current and no power.  With the supplies enabled, it reads 11.93V input,
11.98V output, no current, no power.  I'm not drawing any current at the
moment, so this is reasonable.  The value in the sense register never
reads anything except 0, so I expect to get zero from the current and
power calculations.

I didn't attempt to support changing any of the chip's settings or
enabling the FET.  I'm not sure even how to do that and still fit within
the hwmon framework.  :)

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01 08:59:21 -07:00

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Kernel driver ltc4215
=====================
Supported chips:
* Linear Technology LTC4215
Prefix: 'ltc4215'
Addresses scanned: 0x44
Datasheet:
http://www.linear.com/pc/downloadDocument.do?navId=H0,C1,C1003,C1006,C1163,P17572,D12697
Author: Ira W. Snyder <iws@ovro.caltech.edu>
Description
-----------
The LTC4215 controller allows a board to be safely inserted and removed
from a live backplane.
Usage Notes
-----------
This driver does not probe for LTC4215 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 LTC4215 at address 0x44
on I2C bus #0:
$ modprobe ltc4215 force=0,0x44
Sysfs entries
-------------
The LTC4215 has built-in limits for overvoltage, undervoltage, and
undercurrent warnings. This makes it very likely that the reference
circuit will be used.
in1_input input voltage
in2_input output voltage
in1_min_alarm input undervoltage alarm
in1_max_alarm input overvoltage alarm
curr1_input current
curr1_max_alarm overcurrent alarm
power1_input power usage
power1_alarm power bad alarm