Merge branch 'for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux

[linux-2.6-block.git] / Documentation / hwmon / adm1275.rst

Kernel driver adm1275
=====================

Supported chips:

  * Analog Devices ADM1075

    Prefix: 'adm1075'

    Addresses scanned: -

    Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1075.pdf

  * Analog Devices ADM1272

    Prefix: 'adm1272'

    Addresses scanned: -

    Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1272.pdf

  * Analog Devices ADM1275

    Prefix: 'adm1275'

    Addresses scanned: -

    Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1275.pdf

  * Analog Devices ADM1276

    Prefix: 'adm1276'

    Addresses scanned: -

    Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1276.pdf

  * Analog Devices ADM1278

    Prefix: 'adm1278'

    Addresses scanned: -

    Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1278.pdf

  * Analog Devices ADM1293/ADM1294

    Prefix: 'adm1293', 'adm1294'

    Addresses scanned: -

    Datasheet: http://www.analog.com/media/en/technical-documentation/data-sheets/ADM1293_1294.pdf

Author: Guenter Roeck <linux@roeck-us.net>


Description
-----------

This driver supports hardware monitoring for Analog Devices ADM1075, ADM1272,
ADM1275, ADM1276, ADM1278, ADM1293, and ADM1294 Hot-Swap Controller and
Digital Power Monitors.

ADM1075, ADM1272, ADM1275, ADM1276, ADM1278, ADM1293, and ADM1294 are hot-swap
controllers that allow a circuit board to be removed from or inserted into
a live backplane. They also feature current and voltage readback via an
integrated 12 bit analog-to-digital converter (ADC), accessed using a
PMBus interface.

The driver is a client driver to the core PMBus driver. Please see
Documentation/hwmon/pmbus.rst for details on PMBus client drivers.


Usage Notes
-----------

This driver does not auto-detect devices. You will have to instantiate the
devices explicitly. Please see Documentation/i2c/instantiating-devices.rst for
details.

The ADM1075, unlike many other PMBus devices, does not support internal voltage
or current scaling. Reported voltages, currents, and power are raw measurements,
and will typically have to be scaled.

The shunt value in micro-ohms can be set via device tree at compile-time. Please
refer to the Documentation/devicetree/bindings/hwmon/adm1275.txt for bindings
if the device tree is used.

Platform data support
---------------------

The driver supports standard PMBus driver platform data. Please see
Documentation/hwmon/pmbus.rst for details.


Sysfs entries
-------------

The following attributes are supported. Limits are read-write, history reset
attributes are write-only, all other attributes are read-only.

======================= =======================================================
inX_label		"vin1" or "vout1" depending on chip variant and
			configuration. On ADM1075, ADM1293, and ADM1294,
			vout1 reports the voltage on the VAUX pin.
inX_input		Measured voltage.
inX_min			Minimum Voltage.
inX_max			Maximum voltage.
inX_min_alarm		Voltage low alarm.
inX_max_alarm		Voltage high alarm.
inX_highest		Historical maximum voltage.
inX_reset_history	Write any value to reset history.

curr1_label		"iout1"
curr1_input		Measured current.
curr1_max		Maximum current.
curr1_max_alarm		Current high alarm.
curr1_lcrit		Critical minimum current. Depending on the chip
			configuration, either curr1_lcrit or curr1_crit is
			supported, but not both.
curr1_lcrit_alarm	Critical current low alarm.
curr1_crit		Critical maximum current. Depending on the chip
			configuration, either curr1_lcrit or curr1_crit is
			supported, but not both.
curr1_crit_alarm	Critical current high alarm.
curr1_highest		Historical maximum current.
curr1_reset_history	Write any value to reset history.

power1_label		"pin1"
power1_input		Input power.
power1_input_lowest	Lowest observed input power. ADM1293 and ADM1294 only.
power1_input_highest	Highest observed input power.
power1_reset_history	Write any value to reset history.

			Power attributes are supported on ADM1075, ADM1272,
			ADM1276, ADM1293, and ADM1294.

temp1_input		Chip temperature.
temp1_max		Maximum chip temperature.
temp1_max_alarm		Temperature alarm.
temp1_crit		Critical chip temperature.
temp1_crit_alarm	Critical temperature high alarm.
temp1_highest		Highest observed temperature.
temp1_reset_history	Write any value to reset history.

			Temperature attributes are supported on ADM1272 and
			ADM1278.
======================= =======================================================