Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

GMT G762/G763 PWM Fan controller

Required node properties:

 - "compatible": must be either "gmt,g762" or "gmt,g763"

 - "reg": I2C bus address of the device

 - "clocks": a fixed clock providing input clock frequency

	     on CLK pin of the chip.

Optional properties:

 - "fan_startv": fan startup voltage. Accepted values are 0, 1, 2 and 3.

	       The higher the more.

 - "pwm_polarity": pwm polarity. Accepted values are 0 (positive duty)

	       and 1 (negative duty).

 - "fan_gear_mode": fan gear mode. Supported values are 0, 1 and 2.

If an optional property is not set in .dts file, then current value is kept

unmodified (e.g. u-boot installed value).

Additional information on operational parameters for the device is available

in Documentation/hwmon/g762. A detailed datasheet for the device is available

at http://natisbad.org/NAS/refs/GMT_EDS-762_763-080710-0.2.pdf.

Example g762 node:

   clocks {

	#address-cells = <1>;

	#size-cells = <0>;

	g762_clk: fixedclk {

		 compatible = "fixed-clock";

		 #clock-cells = <0>;

		 clock-frequency = <8192>;

	}

   }

   g762: g762@3e {

	compatible = "gmt,g762";

	reg = <0x3e>;

	clocks = <&g762_clk>

	fan_gear_mode = <0>; /* chip default */

	fan_startv = <1>;    /* chip default */

	pwm_polarity = <0>;  /* chip default */

   };

ina2xx properties

Required properties:

- compatible: Must be one of the following:

	- "ti,ina219" for ina219

	- "ti,ina220" for ina220

	- "ti,ina226" for ina226

	- "ti,ina230" for ina230

- reg: I2C address

Optional properties:

- shunt-resistor

	Shunt resistor value in micro-Ohm

Example:

ina220@44 {

	compatible = "ti,ina220";

	reg = <0x44>;

	shunt-resistor = <1000>;

};

====================

Supported chips:

  * Dallas Semiconductor DS1621

  * Dallas Semiconductor / Maxim Integrated DS1621

    Prefix: 'ds1621'

    Addresses scanned: I2C 0x48 - 0x4f

    Datasheet: Publicly available at the Dallas Semiconductor website

               http://www.dalsemi.com/

    Addresses scanned: none

    Datasheet: Publicly available from www.maximintegrated.com

  * Dallas Semiconductor DS1625

    Prefix: 'ds1621'

    Addresses scanned: I2C 0x48 - 0x4f

    Datasheet: Publicly available at the Dallas Semiconductor website

               http://www.dalsemi.com/

    Prefix: 'ds1625'

    Addresses scanned: none

    Datasheet: Publicly available from www.datasheetarchive.com

  * Maxim Integrated DS1631

    Prefix: 'ds1631'

    Addresses scanned: none

    Datasheet: Publicly available from www.maximintegrated.com

  * Maxim Integrated DS1721

    Prefix: 'ds1721'

    Addresses scanned: none

    Datasheet: Publicly available from www.maximintegrated.com

  * Maxim Integrated DS1731

    Prefix: 'ds1731'

    Addresses scanned: none

    Datasheet: Publicly available from www.maximintegrated.com

Authors:

        Christian W. Zuckschwerdt <zany@triq.net>

reset. Be aware: When testing, it showed that the status of Tout can change

with neither of the alarms set.

Temperature conversion of the DS1621 takes up to 1000ms; internal access to

non-volatile registers may last for 10ms or below.

Since there is no version or vendor identification register, there is

no unique identification for these devices. Therefore, explicit device

instantiation is required for correct device identification and functionality

(one device per address in this address range: 0x48..0x4f).

The DS1625 is pin compatible and functionally equivalent with the DS1621,

but the DS1621 is meant to replace it. The DS1631, DS1721, and DS1731 are

also pin compatible with the DS1621 and provide multi-resolution support.

Additionally, the DS1721 data sheet says the temperature flags (THF and TLF)

are used internally, however, these flags do get set and cleared as the actual

temperature crosses the min or max settings (which by default are set to 75

and 80 degrees respectively).

Temperature Conversion:

-----------------------

DS1621 - 750ms (older devices may take up to 1000ms)

DS1625 - 500ms

DS1631 - 93ms..750ms for 9..12 bits resolution, respectively.

DS1721 - 93ms..750ms for 9..12 bits resolution, respectively.

DS1731 - 93ms..750ms for 9..12 bits resolution, respectively.

Note:

On the DS1621, internal access to non-volatile registers may last for 10ms

or less (unverified on the other devices).

Temperature Accuracy:

---------------------

DS1621: +/- 0.5 degree Celsius (from 0 to +70 degrees)

DS1625: +/- 0.5 degree Celsius (from 0 to +70 degrees)

DS1631: +/- 0.5 degree Celsius (from 0 to +70 degrees)

DS1721: +/- 1.0 degree Celsius (from -10 to +85 degrees)

DS1731: +/- 1.0 degree Celsius (from -10 to +85 degrees)

Note:

Please refer to the device datasheets for accuracy at other temperatures.

Temperature Resolution:

-----------------------

As mentioned above, the DS1631, DS1721, and DS1731 provide multi-resolution

support, which is achieved via the R0 and R1 config register bits, where:

R0..R1

------

 0  0 => 9 bits, 0.5 degrees Celcius

 1  0 => 10 bits, 0.25 degrees Celcius

 0  1 => 11 bits, 0.125 degrees Celcius

 1  1 => 12 bits, 0.0625 degrees Celcius

Note:

At initial device power-on, the default resolution is set to 12-bits.

The resolution mode for the DS1631, DS1721, or DS1731 can be changed from

userspace, via the device 'update_interval' sysfs attribute. This attribute

will normalize the range of input values to the device maximum resolution

values defined in the datasheet as follows:

Resolution    Conversion Time    Input Range

 (C/LSB)       (msec)             (msec)

------------------------------------------------

0.5             93.75              0....94

0.25            187.5              95...187

0.125           375                188..375

0.0625          750                376..infinity

------------------------------------------------

The following examples show how the 'update_interval' attribute can be

used to change the conversion time:

$ cat update_interval

750

$ cat temp1_input

22062

$

$ echo 300 > update_interval

$ cat update_interval

375

$ cat temp1_input

22125

$

$ echo 150 > update_interval

$ cat update_interval

188

$ cat temp1_input

22250

$

$ echo 1 > update_interval

$ cat update_interval

94

$ cat temp1_input

22000

$

$ echo 1000 > update_interval

$ cat update_interval

750

$ cat temp1_input

22062

$

As shown, the ds1621 driver automatically adjusts the 'update_interval'

user input, via a step function. Reading back the 'update_interval' value

after a write operation provides the conversion time used by the device.

Mathematically, the resolution can be derived from the conversion time

via the following function:

   g(x) = 0.5 * [minimum_conversion_time/x]

where:

 -> 'x' = the output from 'update_interval'

 -> 'g(x)' = the resolution in degrees C per LSB.

 -> 93.75ms = minimum conversion time

Kernel driver g762

==================

The GMT G762 Fan Speed PWM Controller is connected directly to a fan

and performs closed-loop or open-loop control of the fan speed. Two

modes - PWM or DC - are supported by the device.

For additional information, a detailed datasheet is available at

http://natisbad.org/NAS/ref/GMT_EDS-762_763-080710-0.2.pdf. sysfs

bindings are described in Documentation/hwmon/sysfs-interface.

The following entries are available to the user in a subdirectory of

/sys/bus/i2c/drivers/g762/ to control the operation of the device.

This can be done manually using the following entries but is usually

done via a userland daemon like fancontrol.

Note that those entries do not provide ways to setup the specific

hardware characteristics of the system (reference clock, pulses per

fan revolution, ...); Those can be modified via devicetree bindings

documented in Documentation/devicetree/bindings/hwmon/g762.txt or

using a specific platform_data structure in board initialization

file (see include/linux/platform_data/g762.h).

  fan1_target: set desired fan speed. This only makes sense in closed-loop

            fan speed control (i.e. when pwm1_enable is set to 2).

  fan1_input: provide current fan rotation value in RPM as reported by

            the fan to the device.

  fan1_div: fan clock divisor. Supported value are 1, 2, 4 and 8.

  fan1_pulses: number of pulses per fan revolution. Supported values

            are 2 and 4.

  fan1_fault: reports fan failure, i.e. no transition on fan gear pin for

            about 0.7s (if the fan is not voluntarily set off).

  fan1_alarm: in closed-loop control mode, if fan RPM value is 25% out

            of the programmed value for over 6 seconds 'fan1_alarm' is

            set to 1.

  pwm1_enable: set current fan speed control mode i.e. 1 for manual fan

            speed control (open-loop) via pwm1 described below, 2 for

            automatic fan speed control (closed-loop) via fan1_target

            above.

  pwm1_mode: set or get fan driving mode: 1 for PWM mode, 0 for DC mode.

  pwm1: get or set PWM fan control value in open-loop mode. This is an

            integer value between 0 and 255. 0 stops the fan, 255 makes

            it run at full speed.

Both in PWM mode ('pwm1_mode' set to 1) and DC mode ('pwm1_mode' set to 0),

when current fan speed control mode is open-loop ('pwm1_enable' set to 1),

the fan speed is programmed by setting a value between 0 and 255 via 'pwm1'

entry (0 stops the fan, 255 makes it run at full speed). In closed-loop mode

('pwm1_enable' set to 2), the expected rotation speed in RPM can be passed to

the chip via 'fan1_target'. In closed-loop mode, the target speed is compared

with current speed (available via 'fan1_input') by the device and a feedback

is performed to match that target value. The fan speed value is computed

based on the parameters associated with the physical characteristics of the

system: a reference clock source frequency, a number of pulses per fan

revolution, etc.

Note that the driver will update its values at most once per second.

The INA230 is a high or low side current shunt and power monitor with an I2C

interface. The INA230 monitors both a shunt voltage drop and bus supply voltage.

The shunt value in micro-ohms can be set via platform data.

The shunt value in micro-ohms can be set via platform data or device tree.

Please refer to the Documentation/devicetree/bindings/i2c/ina2xx.txt for bindings

if the device tree is used.