On Mon, Oct 02, 2023 at 01:46:53PM +0000, Miclaus, Antoniu wrote: > > > -- > 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. Makes sense. Please expand the description with some of this detail so the purpose is clear. The description should answer when do I set this property or not. Rob
