Re: [RESEND PATCH v2 2/2] dt-bindings: iio: Add ltc2983 documentation

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, 2019-10-01 at 10:16 +0100, Jonathan Cameron wrote:
> 
> On Mon, 30 Sep 2019 12:42:47 +0200
> Nuno Sá <nuno.sa@xxxxxxxxxx> wrote:
> 
> > Document the LTC2983 temperature sensor devicetree bindings.
> > 
> > Signed-off-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
> 
> Hi Nuno,
> 
> A few comments inline.  This is a complex one so I'll definitely be
> looking for a review from Rob or Mark,
> 
> Thanks,
> 
> Jonathan
> 
> > ---
> > Changes in v2:
> >  * Drop maxItems in non-array elements;
> >  * Set adi,mux-delay-config-us instead of adi,mux-delay-config;
> >  * Wrapped lines at 80 char;
> >  * Added comas to enum elements;
> >  * Use real units in adi,excitation-current;
> >  * Moved some enums to minimum and maximum;
> >  * Grouped patternProperties and moved reg property as a generic
> > property.
> > 
> >  .../bindings/iio/temperature/adi,ltc2983.yaml | 406
> > ++++++++++++++++++
> >  MAINTAINERS                                   |   1 +
> >  2 files changed, 407 insertions(+)
> >  create mode 100644
> > Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
> > 
> > diff --git
> > a/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yam
> > l
> > b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yam
> > l
> > new file mode 100644
> > index 000000000000..df68b8233e5e
> > --- /dev/null
> > +++
> > b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yam
> > l
> > @@ -0,0 +1,406 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +%YAML 1.2
> > +---
> > +$id: 
> > http://devicetree.org/schemas/iio/temperature/adi,ltc2983.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Analog Devices LTC2983 Multi-sensor Temperature system
> > +
> > +maintainers:
> > +  - Nuno Sá <nuno.sa@xxxxxxxxxx>
> > +
> > +description: |
> > +  Analog Devices LTC2983 Multi-Sensor Digital Temperature
> > Measurement System
> > +  
> > https://www.analog.com/media/en/technical-documentation/data-sheets/2983fc.pdf
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - adi,ltc2983
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  adi,temperature-celcius:
> > +    description:
> > +      If this property is present, the temperature is reported in
> > Celsius.
> > +    type: boolean
> > +
> > +  adi,mux-delay-config-us:
> > +    description:
> > +      The LTC2983 performs 2 or 3 internal conversion cycles per
> > temperature
> > +      result. Each conversion cycle is performed with different
> > excitation and
> > +      input multiplexer configurations. Prior to each conversion,
> > these
> > +      excitation circuits and input switch configurations are
> > changed and an
> > +      internal 1ms delay ensures settling prior to the conversion
> > cycle in most
> > +      cases. An extra delay can be configured using this property.
> > The value is
> > +      rounded to nearest 100us.
> > +    allOf:
> > +      - $ref: /schemas/types.yaml#/definitions/uint32
> > +      - maximum: 255
> > +
> > +  adi,filter-notch-freq:
> > +    description:
> > +      Set's the default setting of the digital filter. The default
> > is
> > +      simultaneous 50/60Hz rejection.
> > +    allOf:
> > +      - $ref: /schemas/types.yaml#/definitions/uint32
> > +      - minimum: 0
> > +      - maximum: 2
> 
> This one is an oddity and you should define what the 3 values mean.
> If the sensor had supported no notch rejection at all rather than
> just
> 50, 60, 50/60 I would have suggested two bools but as it stands I
> guess
> this will just need to be an enum.

Yes, I guess we need the enum or like it is right know. I will add
meaning to the values.

> > +
> > +  '#address-cells':
> > +    const: 1
> > +
> > +  '#size-cells':
> > +    const: 0
> > +
> > +patternProperties:
> > +  ".*@([1-9]|1[0-9]|20)$":
> > +    type: object
> > +
> > +    properties:
> > +      reg:
> > +        description: |
> > +          The channel number. It can be connected to one of the 20
> > channels of
> > +          the device.
> > +        minimum: 1
> > +        maximum: 20
> > +
> > +    required:
> > +      - reg
> > +
> > +    patternProperties:
> > +      "^thermocouple@.*":
> > +        type: object
> > +        description: |
> > +          Represents a thermocouple sensor which is connected to
> > one of the device
> > +          channels.
> > +
> > +        properties:
> > +          adi,sensor-type:
> > +            description: |
> > +              Identifies the type of thermocouple connected to the
> > device.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - minimum: 1
> > +              - maximum: 8
> 
> Meaning of values should be defined...

ack.

> > +
> > +          adi,sensor-config:
> > +            description: |
> > +              Raw value which set's the sensor configuration. Look
> > at table 14
> > +              of the datasheet for how to set this value for
> > thermocouples.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - minimum: 1
> > +              - maximun: 15
> Hmm.  Whilst there are quite a few things in here, it would be nice
> to break it up
> into human readable elements.  It's only 3 things and there are a
> bunch of don't
> care states it seems.

Yes, now that I gave it more thought, I see I was lazy here. I will
replace this property with 2 other properties. A boolean for single-
Ended and another uint32 prop for open-circuit-current. With those 2
properties I can set the sensor-config bits.
 
> > +
> > +          adi,cold-junction-handle:
> > +            description: |
> > +              Phandle which points to a sensor object responsible
> > for measuring
> > +              the thermocouple cold junction temperature.
> > +            $ref: "/schemas/types.yaml#/definitions/phandle"
> > +
> > +          adi,custom-sensor:
> > +            description: |
> > +              This is a table, where each entry should be a pair
> > of
> > +              voltage(mv)-temperature(K). The entries must be
> > given in nv and uK
> > +              so that, the original values must be multiplied by
> > 1000000. For
> > +              more details look at table 69 and 70.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/int64-array
> > +              - minItems: 6
> > +              - maxItems: 128
> > +
> > +        required:
> > +          - adi,sensor-type
> > +
> > +      "^diode@.*":
> > +        type: object
> > +        description: |
> > +          Represents a diode sensor which is connected to one of
> > the device
> > +          channels.
> > +
> > +        properties:
> > +          adi,sensor-type:
> > +            description: Identifies the sensor as a diode.
> > +            const: 28
> > +
> > +          adi,sensor-config:
> > +            description: |
> > +              Raw value which set's the sensor configuration. Look
> > at table 17
> > +              of the datasheet for how to set this value for
> > diodes.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - minimum: 0
> > +              - maximum: 7
> Another one I'd like to see broken up.

ack. I can use 3 booleans here.

> > +
> > +          adi,excitation-current-microamp:
> > +            description: |
> > +              This property controls the magnitude of the
> > excitation current
> > +              applied to the diode. Depending on the number of
> > conversions
> > +              cycles, this property will assume different
> > predefined values on
> > +              each cycle. Just set the value of the first cycle
> > (1l).
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - enum: [10, 20, 40, 80]
> > +
> > +          adi,ideal-factor-value:
> > +            description: |
> > +              This property sets the diode ideality factor. The
> > real value must
> > +              be multiplied by 1000000 to remove the fractional
> > part. For more
> > +              information look at table 20 of the datasheet.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +
> > +        required:
> > +          - adi,sensor-type
> > +
> > +      "^rtd@.*":
> > +        type: object
> > +        description: |
> > +          Represents a rtd sensor which is connected to one of the
> > device channels.
> > +
> > +        properties:
> > +          reg:
> > +            minimum: 2
> > +
> > +          adi,sensor-type:
> > +            description: Identifies the type of RTD connected to
> > the device.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - minimum: 10
> > +              - maximum: 17
> > +
> > +          adi,rsense-handle:
> > +            description: |
> > +              Phandle pointing to a rsense object associated with
> > this RTD.
> > +            $ref: "/schemas/types.yaml#/definitions/phandle"
> > +
> > +          adi,sensor-config:
> > +            description: |
> > +              Raw value which set's the sensor configuration. Look
> > at table 28
> > +              of the datasheet for how to set this value for
> > RTD's.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - enum: [0, 1, 4, 5, 8, 9, 10, 12, 13, 14]
> 
> Another one to break up into it's parts, which would also get rid of
> the
> enum with gaps element.

Will do that.

> 
> > +
> > +          adi,excitation-current-microamp:
> > +            description: |
> > +              This property controls the magnitude of the
> > excitation current
> > +              applied to the RTD.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - enum: [5, 10, 25, 50, 100, 250, 500, 1000]
> > +
> > +          adi,rtd-curve:
> > +            description: |
> > +              This property set the RTD curve used and the
> > corresponding
> > +              Callendar-VanDusen constants. Look at table 30 of
> > the datasheet.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - minimum: 0
> > +              - maximum: 3
> > +
> > +          adi,custom-sensor:
> > +            description: |
> > +              This is a table, where each entry should be a pair
> > of
> > +              resistance(ohm)-temperature(K). The entries added
> > here are in uohm
> > +              and uK. For more details values look at table 74 and
> > 75.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint64-
> > array
> > +              - minItems: 6
> > +              - maxItems: 128
> > +
> > +        required:
> > +          - adi,sensor-type
> > +          - adi,rsense-handle
> > +
> > +      "^thermistor@.*":
> > +        type: object
> > +        description: |
> > +          Represents a thermistor sensor which is connected to one
> > of the device
> > +          channels.
> > +
> > +        properties:
> > +          adi,sensor-type:
> > +            description: |
> > +              Identifies the type of thermistor connected to the
> > +              device.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - minimum: 19
> > +              - maximum: 25
> > +
> > +          adi,rsense-handle:
> > +            description: |
> > +              Phandle pointing to a rsense object associated with
> > this
> > +              thermistor.
> > +            $ref: "/schemas/types.yaml#/definitions/phandle"
> > +
> > +          adi,sensor-config:
> > +            description: |
> > +              Raw value which set's the sensor configuration. Look
> > at table 52
> > +              of the datasheet for how to set this value for
> > thermistors.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - minimum: 0
> > +              - maximum: 4
> Nasty as value 3 is reserved.  So break this one up into it's parts
> as well.

Arghh, that is obviously a problem. Will do that.

> > +
> > +          adi,excitation-current-nanoamp:
> > +            description: |
> > +              This property controls the magnitude of the
> > excitation current
> > +              applied to the thermistor. Value 0 set's the sensor
> > in auto-range
> > +              mode.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint32
> > +              - enum: [0, 250, 500, 1000, 5000, 10000, 25000,
> > 50000, 100000,
> > +                       250000, 500000, 1000000]
> > +
> > +          adi,custom-sensor:
> > +            description: |
> > +              This is a table, where each entry should be a pair
> > of
> > +              resistance(ohm)-temperature(K). The entries added
> > here are in uohm
> > +              and uK only for custom thermistors. For more details
> > look at table
> > +              78 and 79. Steinhart-Hart coefficients are also
> > supported and can
> > +              be programmed into the device memory using this
> > property. For
> > +              Steinhart sensors, this table has a constant size of
> > 6 entries
> > +              (defining the coefficients) and the values are given
> > in the raw
> > +              format. Look at table 82 for more information.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint64-
> > array
> > +              - minItems: 6
> > +              - maxItems: 128
> > +
> > +        required:
> > +          - adi,sensor-type
> > +          - adi,rsense-handle
> > +
> > +      "^adc@.*":
> > +        type: object
> > +        description: Represents a channel which is being used as a
> > direct adc.
> > +
> > +        properties:
> > +          adi,sensor-type:
> > +            description: Identifies the sensor as a direct adc.
> > +            const: 30
> > +
> > +          adi,single-ended:
> > +            description: Boolean property which set's the adc as
> > single-ended.
> > +            type: boolean
> > +
> > +        required:
> > +          - adi,sensor-type
> > +
> > +      "^rsense@.*":
> > +        type: object
> > +        description: |
> > +          Represents a rsense which is connected to one of the
> > device channels.
> > +          Rsense are used by thermistors and RTD's.
> > +
> > +        properties:
> > +          reg:
> > +            minimum: 2
> > +
> > +          adi,sensor-type:
> > +            description: Identifies the sensor as a rsense.
> > +            const: 29
> > +
> > +          adi,rsense-val-micro-ohms:
> > +            description: |
> > +              Sets the value of the sense resistor. Look at table
> > 20 of the
> > +              datasheet for information.
> > +            allOf:
> > +              - $ref: /schemas/types.yaml#/definitions/uint64
> > +
> > +        required:
> > +          - adi,sensor-type
> > +          - adi, rsense-val
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - interrupts
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/interrupt-controller/irq.h>
> > +    spi0 {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +
> > +        sensor_ltc2983: ltc2983@0 {
> > +                compatible = "adi,ltc2983";
> > +                reg = <0>;
> > +
> > +                #address-cells = <1>;
> > +                #size-cells = <0>;
> > +
> > +                adi,temperature-celcius;
> > +                interrupts = <20 IRQ_TYPE_EDGE_RISING>;
> > +                interrupt-parent = <&gpio>;
> > +
> > +                thermocouple@18 {
> > +                        reg = <18>;
> > +                        adi,sensor-type = <8>; //Type B
> > +                        adi,sensor-config = <1>; //Differential,
> > open-circuit current
> > +                        adi,cold-junction-handle = <&diode5>;
> > +                };
> > +
> > +                diode5: diode@5 {
> > +                        reg = <5>;
> > +                        adi,sensor-type = <28>;
> > +                };
> > +
> > +                rsense2: rsense@2 {
> > +                        reg = <2>;
> > +                        adi,sensor-type = <29>;
> > +                        adi,rsense-val-micro-ohms = /bits/ 64
> > <1200000000>; //1.2Kohms
> > +                };
> > +
> > +                rtd@14 {
> > +                        reg = <14>;
> > +                        adi,sensor-type = <15>; //PT1000
> > +                        /*2-wire, internal gnd, no current
> > rotation*/
> > +                        adi,sensor-config = <1>;
> > +                        adi,excitation-current = <7>; //500uA
> > +                        adi,rsense-handle = <&rsense2>;
> > +                };
> > +
> > +                adc@10 {
> > +                        reg = <10>;
> > +                        adi,sensor-type = <30>;
> > +                        adi,single-ended;
> > +                };
> > +
> > +                thermistor@12 {
> > +                        reg = <12>;
> > +                        adi,sensor-type = <26>; //Steinhart
> > +                        adi,rsense-handle = <&rsense2>;
> > +                        adi,custom-sensor = /bits/ 64 <0x00F371EC
> > 0x12345678
> > +                                        0x2C0F8733 0x10018C66
> > 0xA0FEACCD
> > +                                        0x90021D99>; //6 entries
> > +                };
> > +
> > +                thermocouple@20 {
> > +                        reg = <20>;
> > +                        adi,sensor-type = <9>; //custom
> > thermocouple
> > +                        adi,sensor-config = <8>; //single-ended
> > +                        adi,custom-sensor = /bits/ 64
> > +                                 <(-50220000) 0
> > +                                  (-30200000) 99100000
> > +                                  (-5300000) 135400000
> > +                                  0 273150000
> > +                                  40200000 361200000
> > +                                  55300000 522100000
> > +                                  88300000 720300000
> > +                                  132200000 811200000
> > +                                  188700000 922500000
> > +                                  460400000 1000000000>; //10
> > pairs
> > +               };
> > +
> > +        };
> > +    };
> > +...
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 14a256e785ca..f747a9dc27f5 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -9497,6 +9497,7 @@ W:	
> > http://ez.analog.com/community/linux-device-drivers
> >  L:	linux-iio@xxxxxxxxxxxxxxx
> >  S:	Supported
> >  F:	drivers/iio/temperature/ltc2983.c
> > +F:	Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.y
> > aml
> >  
> >  LTC4261 HARDWARE MONITOR DRIVER
> >  M:	Guenter Roeck <linux@xxxxxxxxxxxx>





[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux