-- Antoniu Miclăuş > -----Original Message----- > From: Conor Dooley <conor@xxxxxxxxxx> > Sent: Monday, October 2, 2023 4:01 PM > To: Miclaus, Antoniu <Antoniu.Miclaus@xxxxxxxxxx> > Cc: Jean Delvare <jdelvare@xxxxxxxx>; Guenter Roeck <linux@roeck- > us.net>; Rob Herring <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski > <krzysztof.kozlowski+dt@xxxxxxxxxx>; Conor Dooley > <conor+dt@xxxxxxxxxx>; Jonathan Corbet <corbet@xxxxxxx>; linux- > hwmon@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; linux-doc@xxxxxxxxxxxxxxx > Subject: Re: [PATCH v2 1/2] dt-bindings: hwmon: ltc2991: add bindings > > [External] > > Hey, > > On Mon, Oct 02, 2023 at 01:18:14PM +0300, Antoniu Miclaus wrote: > > Add dt-bindings for ltc2991 octal i2c voltage, current and temperature > > monitor. > > > > Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> > > --- > > changes in v2: > > - make compatible const type > > - remove `|` where not necessary > > - switch to micro-ohms for the shunt resistor property > > - add vendor prefix for temperature-enable > > Thanks for the updates... > > > .../bindings/hwmon/adi,ltc2991.yaml | 114 ++++++++++++++++++ > > 1 file changed, 114 insertions(+) > > create mode 100644 > Documentation/devicetree/bindings/hwmon/adi,ltc2991.yaml > > > > diff --git a/Documentation/devicetree/bindings/hwmon/adi,ltc2991.yaml > b/Documentation/devicetree/bindings/hwmon/adi,ltc2991.yaml > > new file mode 100644 > > index 000000000000..3811ea07a04f > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/hwmon/adi,ltc2991.yaml > > @@ -0,0 +1,114 @@ > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > > +%YAML 1.2 > > +--- > > + > > +$id: http://devicetree.org/schemas/hwmon/adi,ltc2991.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: Analog Devices LTC2991 Octal I2C Voltage, Current and Temperature > Monitor > > + > > +maintainers: > > + - Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> > > + > > +description: | > > + The LTC2991 is used to monitor system temperatures, voltages and > currents. > > + Through the I2C serial interface, the eight monitors can individually > measure > > + supply voltages and can be paired for differential measurements of > current > > + sense resistors or temperature sensing transistors. > > + > > + Datasheet: > > + https://www.analog.com/en/products/ltc2991.html > > + > > +properties: > > + compatible: > > + const: adi,ltc2991 > > + > > + reg: > > + maxItems: 1 > > + > > + '#address-cells': > > + const: 1 > > + > > + '#size-cells': > > + const: 0 > > + > > + vcc-supply: true > > + > > +patternProperties: > > + "^channel@[0-3]$": > > + type: object > > + description: > > + Represents the differential/temperature channels. > > + > > + properties: > > + reg: > > + description: > > + The channel number. LTC2991 can monitor 4 currents/temperatures. > > + items: > > + minimum: 0 > > + maximum: 3 > > + > > + shunt-resistor-micro-ohms: > > + description: > > + The value of curent sense resistor in miliohms. Enables differential > > + input pair. > > + > > + adi,temperature-enable: > > + description: > > + Enables temperature readings for a input pair. > > + type: boolean > > ...but I did not see an answer to my question on v1: > TBH, this seems like it is used just to control software behaviour. > Why would you want to actually disable this in DT? > In other words, is there something in that hardware that precludes > measuring temperature for channels that do not contain this property? > > Thanks, > Conor. > Sorry for missing that. I took in consideration this approach based on the pin functions described in the datasheet (page 8 of 32). For example the V1 pin of the part can support 3 different configurations: "V1 (Pin 1): First Monitor Input. This pin can be configured as a single-ended input (0V to 4.9V) or the positive inputfor a differential or remote diode temperature measurement (in combination with V2)." Moreover, looking at the multiple typical applications examples at the end of the datasheet there is a specific adjacent hardware circuit connected to this part for the temperature measurements configurations. Thank you, Antoniu > > + > > +required: > > + - compatible > > + - reg > > + - vcc-supply > > + > > +additionalProperties: false > > + > > +examples: > > + - | > > + i2c { > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + hwmon@48 { > > + compatible = "adi,ltc2991"; > > + reg = <0x48>; > > + vcc-supply = <&vcc>; > > + }; > > + }; > > + - | > > + i2c { > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + hwmon@48 { > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + compatible = "adi,ltc2991"; > > + reg = <0x48>; > > + vcc-supply = <&vcc>; > > + > > + channel@0 { > > + reg = <0x0>; > > + shunt-resistor-micro-ohms = <100000>; > > + }; > > + > > + channel@1 { > > + reg = <0x1>; > > + shunt-resistor-micro-ohms = <100000>; > > + }; > > + > > + channel@2 { > > + reg = <0x2>; > > + temperature-enable; > > + }; > > + > > + channel@3 { > > + reg = <0x3>; > > + temperature-enable; > > + }; > > + }; > > + }; > > +... > > -- > > 2.42.0 > >
