Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 51 insertions, 0 deletions

diff --git a/Documentation/hwmon/ltc4215 b/Documentation/hwmon/ltc4215
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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 have to
+instantiate the devices explicitly.
+
+Example: the following will load the driver for an LTC4215 at address 0x44
+on I2C bus #0:
+$ modprobe ltc4215
+$ echo ltc4215 0x44 > /sys/bus/i2c/devices/i2c-0/new_device
+
+
+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