On Wed, Aug 02, 2017 at 04:45:38PM +0930, Andrew Jeffery wrote: > Signed-off-by: Andrew Jeffery <andrew@xxxxxxxx> > --- > .../devicetree/bindings/hwmon/pmbus/max31785.txt | 126 +++++++++++++++++++++ > 1 file changed, 126 insertions(+) > create mode 100644 Documentation/devicetree/bindings/hwmon/pmbus/max31785.txt > > diff --git a/Documentation/devicetree/bindings/hwmon/pmbus/max31785.txt b/Documentation/devicetree/bindings/hwmon/pmbus/max31785.txt > new file mode 100644 > index 000000000000..8ddc4ea1958d > --- /dev/null > +++ b/Documentation/devicetree/bindings/hwmon/pmbus/max31785.txt > @@ -0,0 +1,126 @@ > +Bindings for the Maxim MAX31785 Intelligent Fan Controller > +========================================================== This is the second fan controller binding I've seen recently. The other being hwmon/aspeed-pwm-tacho.txt. I think some of this needs to be common. There's only so many types of fans, right? And we have the thermal binding which you don't appear to tie into. > + > +Reference: > +[1] https://datasheets.maximintegrated.com/en/ds/MAX31785.pdf > + > +Required properties: > +- compatible : One of "maxim,max31785" or "maxim,max31785a" > +- reg : I2C address, one of 0x52, 0x53, 0x54, 0x55. > +- #address-cells : Must be 1 > +- #size-cells : Must be 0 > + > +Optional properties: > +- use-stored-presence : Do not treat the devicetree description as canon for Is this maxim specific? If so, needs a vendor prefix. > + fan presence (the 'installed' bit of FAN_CONFIG_*). > + Instead, rely on the on the default value store of > + the device to populate it. > + > +Capabilities are configured through subnodes of the controller's node. > + > +Fans > +---- > + > +Only fans with subnodes present will be considered as installed. If > +use-stored-presence is present in the parent node, then only fans that are both > +defined in the devicetree and have their installed bit set are considered > +installed. > + > +Required subnode properties: > +- compatible : Must be "pmbus-fan" What defines a pmbus-fan? Sounds generic, but then you have all these maxim specific properties. > +- reg : The PMBus page the properties apply to. > +- maxim,fan-rotor-input : The type of rotor measurement provided to the > + controller. Must be either "tach" for tachometer > + pulses or "lock" for a locked-rotor signal. > +- maxim,fan-lock-polarity: Required iff maxim,fan-rotor-input is "lock". Valid > + values are "low" for active low, "high" for active > + high. > + > +Optional subnode properties: > +- fan-mode : "rpm" or "pwm". Default value is "pwm". > +- tach-pulses : Tachometer pulses per revolution. Valid values are > + 1, 2, 3 or 4. The default is 1. > +- maxim,fan-no-fault-ramp: Do not ramp the fan to 100% PWM duty on detecting a > + fan fault > +- maxim,fan-startup : The number of rotations required before taking > + emergency action for an unresponsive fan and driving > + it with 100% or 0% PWM duty, depending on the state > + of maxim,fan-no-fault-ramp. Valid values are 0 > + (automatic spin-up disabled), 2, 4, or 8. Default > + value is 0. > +- maxim,fan-health : Enable automated fan health check > +- maxim,fan-ramp : Configures how fast the device ramps the PWM duty > + cycle from one value to another. Valid values are 0 > + to 7 inclusive, with values 0 - 2 configuring a > + 1000ms update rate and 1 - 3% duty respective duty > + increase, and 3 - 7 a 200ms update rate with a 1 - > + 5% respective duty increase. Default value is 0. > +- maxim,fan-no-watchdog : Do not ramp fan to 100% PWM duty on failure to > + update desired fan rate inside 10s. This implies > + maxim,tmp-no-fault-ramp > +- maxim,tmp-no-fault-ramp: Do not ramp fan to 100% PWM duty on temperature > + sensor fault detection. This implies > + maxim,fan-no-watchdog > +- maxim,tmp-hysteresis : The temperature hysteresis used to determine > + transitions to lower fan speed bands in the > + temperature/fan rate lookup table. Valid values are > + 2, 4, 6 or 8 (degrees celcius). Default value is 2. > +- maxim,fan-dual-tach : Enable dual tachometer functionality > +- maxim,fan-pwm-freq : The PWM frequency. Valid values are 30, 50, 100, 150 > + and 25000 (Hz). Default value is 30Hz. > +- maxim,fan-lookup-table : A 16-element cell array of alternating temperature > + and rate values representing the look up table. The > + rate units are set through the fan-mode property. > +- maxim,fan-fault-pin-mon: Ramp fans to 100% PWM duty when the FAULT pin is > + asserted > + > +Temperature > +----------- > + > +Required subnode properties: > +- compatible : Must be "pmbus-temperature" > +- reg : The PMBus page the properties apply to. > + > +Optional subnode properties: > +- maxim,tmp-offset : Valid values are 0 - 30 (degrees celcius) inclusive. > + Default value is 0. > +- maxim,tmp-fans : An array of fan indexes whose fans are controlled by > + the current temperature sensor. Fans are indexed from > + zero. The valid values are 0 - 5 inclusive. Why not use a phandle here. > + > +Example: > + fan-max31785: max31785@52 { > + reg = <0x52>; > + compatible = "maxim,max31785"; > + #address-cells = <1>; > + #size-cells = <0>; > + > + fan@0 { > + compatible = "pmbus-fan"; > + reg = <0>; > + mode = "rpm"; > + tach-pulses = <1>; > + maxim,fan-rotor-input = "tach"; > + maxim,fan-dual-tach; > + }; > + > + fan@1 { > + compatible = "pmbus-fan"; > + reg = <1>; > + mode = "rpm"; > + tach-pulses = <1>; > + maxim,fan-rotor-input = "tach"; > + maxim,tmp-hysteresis = <2>; > + maxim,fan-lookup-table = < > + /* Temperature RPM */ > + 0 1000 > + 10 2000 > + 20 3000 > + 30 4000 > + 40 5000 > + 50 6000 > + 60 7000 > + 70 8000 > + >; > + }; > + }; > -- > 2.11.0 > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
