[PATCH v3 2/4] dt-bindings: iio: temperature: ltc2983: refine

[Cosmin Tanislav]

From: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>

 * make sure addresses are represented as hex
 * add note about wrong unit value for adi,mux-delay-config-us
 * simplify descriptions
 * add descriptions for the items of custom sensor tables
 * add default property values where applicable
 * use conditionals to extend minimum reg value
   for single ended sensors
 * remove " around phandle schema $ref
 * remove label from example and use generic temperature
   sensor name

Signed-off-by: Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>
---
 .../bindings/iio/temperature/adi,ltc2983.yaml | 270 ++++++++++--------
 1 file changed, 144 insertions(+), 126 deletions(-)

diff --git a/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
index 722781aa4697..a878fd84636f 100644
--- a/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
+++ b/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml
@@ -26,25 +26,25 @@ properties:
 
   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.
+      Extra delay prior to each conversion, in addition to the internal 1ms
+      delay, for the multiplexer to switch input configurations and
+      excitation values.
+
+      This property is supposed to be in microseconds, but to maintain
+      compatibility, this value will be multiplied by 100 before usage.
     maximum: 255
+    default: 0
 
   adi,filter-notch-freq:
     description:
-      Set's the default setting of the digital filter. The default is
-      simultaneous 50/60Hz rejection.
+      Notch frequency of the digital filter.
       0 - 50/60Hz rejection
       1 - 60Hz rejection
       2 - 50Hz rejection
     $ref: /schemas/types.yaml#/definitions/uint32
     minimum: 0
     maximum: 2
+    default: 0
 
   '#address-cells':
     const: 1
@@ -53,19 +53,19 @@ properties:
     const: 0
 
 patternProperties:
-  "@([1-9]|1[0-9]|20)$":
+  "@([0-9a-f]+)$":
     type: object
-
+    description: Sensor.
     properties:
       reg:
         description:
-          The channel number. It can be connected to one of the 20 channels of
-          the device.
+          Channel number. Connects the sensor to the channel with this number
+          of the device.
         minimum: 1
         maximum: 20
 
       adi,sensor-type:
-        description: Identifies the type of sensor connected to the device.
+        description: Type of sensor connected to the device.
         $ref: /schemas/types.yaml#/definitions/uint32
 
     required:
@@ -74,10 +74,7 @@ patternProperties:
 
   "^thermocouple@":
     type: object
-    description:
-      Represents a thermocouple sensor which is connected to one of the device
-      channels.
-
+    description: Thermocouple sensor.
     properties:
       adi,sensor-type:
         description: |
@@ -95,87 +92,86 @@ patternProperties:
         maximum: 9
 
       adi,single-ended:
-        description:
-          Boolean property which set's the thermocouple as single-ended.
+        description: Whether the sensor is single-ended.
         type: boolean
 
       adi,sensor-oc-current-microamp:
-        description:
-          This property set's the pulsed current value applied during
-          open-circuit detect.
+        description: Pulsed current value applied during open-circuit detect.
         enum: [10, 100, 500, 1000]
+        default: 10
 
       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"
+          Sensor responsible for measuring the thermocouple cold junction
+          temperature.
+        $ref: /schemas/types.yaml#/definitions/phandle
 
       adi,custom-thermocouple:
         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.
-          Note should be signed, but dtc doesn't currently maintain the
-          sign.
+          Used for digitizing custom thermocouples.
+          See Page 59 of the datasheet.
         $ref: /schemas/types.yaml#/definitions/uint64-matrix
         minItems: 3
         maxItems: 64
         items:
-          minItems: 2
-          maxItems: 2
+          items:
+            - description: Voltage point in nV, signed.
+            - description: Temperature point in uK.
+
+    allOf:
+      - if:
+          properties:
+            adi,sensor-type:
+              const: 9
+        then:
+          required:
+            - adi,custom-thermocouple
 
   "^diode@":
     type: object
-    description:
-      Represents a diode sensor which is connected to one of the device
-      channels.
-
+    description: Diode sensor.
     properties:
       adi,sensor-type:
-        description: Identifies the sensor as a diode.
+        description: Sensor type for diodes.
         $ref: /schemas/types.yaml#/definitions/uint32
         const: 28
 
       adi,single-ended:
-        description: Boolean property which set's the diode as single-ended.
+        description: Whether the sensor is single-ended.
         type: boolean
 
       adi,three-conversion-cycles:
         description:
-          Boolean property which set's three conversion cycles removing
-          parasitic resistance effects between the LTC2983 and the diode.
+          Whether to use three conversion cycles to remove parasitic
+          resistance between the device and the diode.
         type: boolean
 
       adi,average-on:
         description:
-          Boolean property which enables a running average of the diode
-          temperature reading. This reduces the noise when the diode is used
-          as a cold junction temperature element on an isothermal block
-          where temperatures change slowly.
+          Whether to use a running average of the diode temperature
+          reading to reduce the noise when the diode is used as a cold
+          junction temperature element on an isothermal block where
+          temperatures change slowly.
         type: boolean
 
       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).
+          Magnitude of the 1l excitation current applied to the diode.
+          4l excitation current will be 4 times this value, and 8l
+          excitation current will be 8 times value.
         enum: [10, 20, 40, 80]
+        default: 10
 
       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.
+          Diode ideality factor.
+          Set this property to 1000000 times the real value.
         $ref: /schemas/types.yaml#/definitions/uint32
+        default: 0
 
   "^rtd@":
     type: object
-    description:
-      Represents a rtd sensor which is connected to one of the device channels.
-
+    description: RTD sensor.
     properties:
       reg:
         minimum: 2
@@ -197,56 +193,57 @@ patternProperties:
         maximum: 18
 
       adi,rsense-handle:
-        description:
-          Phandle pointing to a rsense object associated with this RTD.
-        $ref: "/schemas/types.yaml#/definitions/phandle"
+        description: Associated sense resistor sensor.
+        $ref: /schemas/types.yaml#/definitions/phandle
 
       adi,number-of-wires:
         description:
-          Identifies the number of wires used by the RTD. Setting this
-          property to 5 means 4 wires with Kelvin Rsense.
+          Number of wires used by the RTD.
+          5 means 4 wires with Kelvin sense resistor.
         $ref: /schemas/types.yaml#/definitions/uint32
         enum: [2, 3, 4, 5]
+        default: 2
 
       adi,rsense-share:
         description:
-          Boolean property which enables Rsense sharing, where one sense
-          resistor is used for multiple 2-, 3-, and/or 4-wire RTDs.
+          Whether to enable sense resistor sharing, where one sense
+          resistor is used by multiple sensors.
         type: boolean
 
       adi,current-rotate:
         description:
-          Boolean property which enables excitation current rotation to
-          automatically remove parasitic thermocouple effects. Note that
-          this property is not allowed for 2- and 3-wire RTDs.
+          Whether to enable excitation current rotation to automatically
+          remove parasitic thermocouple effects.
         type: boolean
 
       adi,excitation-current-microamp:
-        description:
-          This property controls the magnitude of the excitation current
-          applied to the RTD.
+        description: Excitation current applied to the RTD.
         enum: [5, 10, 25, 50, 100, 250, 500, 1000]
+        default: 5
 
       adi,rtd-curve:
         description:
-          This property set the RTD curve used and the corresponding
-          Callendar-VanDusen constants. Look at table 30 of the datasheet.
+          RTD curve and the corresponding Callendar-VanDusen constants.
+          0 - European
+          1 - American
+          2 - Japanese
+          3 - ITS-90
         $ref: /schemas/types.yaml#/definitions/uint32
         minimum: 0
         maximum: 3
+        default: 0
 
       adi,custom-rtd:
         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.
+          Used for digitizing custom RTDs.
+          See Page 62 of the datasheet.
         $ref: /schemas/types.yaml#/definitions/uint64-matrix
+        minItems: 3
+        maxItems: 64
         items:
-          minItems: 3
-          maxItems: 64
           items:
-            minItems: 2
-            maxItems: 2
+            - description: Resistance point in uOhms.
+            - description: Temperature point in uK.
 
     required:
       - adi,rsense-handle
@@ -254,12 +251,25 @@ patternProperties:
     dependencies:
       adi,current-rotate: [ "adi,rsense-share" ]
 
+    allOf:
+      - if:
+          properties:
+            adi,number-of-wires:
+              enum: [2, 3]
+        then:
+          properties:
+            adi,current-rotate: false
+      - if:
+          properties:
+            adi,sensor-type:
+              const: 18
+        then:
+          required:
+            - adi,custom-rtd
+
   "^thermistor@":
     type: object
-    description:
-      Represents a thermistor sensor which is connected to one of the device
-      channels.
-
+    description: Thermistor sensor.
     properties:
       adi,sensor-type:
         description:
@@ -277,61 +287,53 @@ patternProperties:
         maximum: 27
 
       adi,rsense-handle:
-        description:
-          Phandle pointing to a rsense object associated with this
-          thermistor.
-        $ref: "/schemas/types.yaml#/definitions/phandle"
+        description: Associated sense resistor sensor.
+        $ref: /schemas/types.yaml#/definitions/phandle
 
       adi,single-ended:
-        description:
-          Boolean property which set's the thermistor as single-ended.
+        description: Whether the sensor is single-ended.
         type: boolean
 
       adi,rsense-share:
         description:
-          Boolean property which enables Rsense sharing, where one sense
-          resistor is used for multiple thermistors. Note that this property
-          is ignored if adi,single-ended is set.
+          Whether to enable sense resistor sharing, where one sense
+          resistor is used by multiple sensors.
         type: boolean
 
       adi,current-rotate:
         description:
-          Boolean property which enables excitation current rotation to
-          automatically remove parasitic thermocouple effects.
+          Whether to enable excitation current rotation to automatically
+          remove parasitic thermocouple effects.
         type: boolean
 
       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.
+          Excitation current applied to the thermistor.
+          0 sets the sensor in auto-range mode.
         $ref: /schemas/types.yaml#/definitions/uint32
         enum: [0, 250, 500, 1000, 5000, 10000, 25000, 50000, 100000, 250000,
                500000, 1000000]
+        default: 0
+
+      adi,custom-steinhart:
+        description:
+          Steinhart-Hart coefficients in raw format, used for digitizing
+          custom thermistors.
+          See Page 68 of the datasheet.
+        $ref: /schemas/types.yaml#/definitions/uint32-array
+        maxItems: 6
 
       adi,custom-thermistor:
         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.
+          Used for digitizing custom thermistors.
+          See Page 65 of the datasheet.
         $ref: /schemas/types.yaml#/definitions/uint64-matrix
         minItems: 3
         maxItems: 64
         items:
-          minItems: 2
-          maxItems: 2
-
-      adi,custom-steinhart:
-        description:
-          Steinhart-Hart coefficients are also supported and can
-          be programmed into the device memory using this property. For
-          Steinhart sensors the coefficients are given in the raw
-          format. Look at table 82 for more information.
-        $ref: /schemas/types.yaml#/definitions/uint32-array
-        items:
-          minItems: 6
-          maxItems: 6
+          items:
+            - description: Resistance point in uOhms.
+            - description: Temperature point in uK.
 
     required:
       - adi,rsense-handle
@@ -339,40 +341,56 @@ patternProperties:
     dependencies:
       adi,current-rotate: [ "adi,rsense-share" ]
 
+    allOf:
+      - if:
+          properties:
+            adi,sensor-type:
+              const: 26
+        then:
+          properties:
+            adi,excitation-current-nanoamp:
+              default: 1000
+          required:
+            - adi,custom-steinhart
+      - if:
+          properties:
+            adi,sensor-type:
+              const: 27
+        then:
+          properties:
+            adi,excitation-current-nanoamp:
+              default: 1000
+          required:
+            - adi,custom-thermistor
+
   "^adc@":
     type: object
-    description: Represents a channel which is being used as a direct adc.
-
+    description: Direct ADC sensor.
     properties:
       adi,sensor-type:
-        description: Identifies the sensor as a direct adc.
+        description: Sensor type for direct ADC sensors.
         $ref: /schemas/types.yaml#/definitions/uint32
         const: 30
 
       adi,single-ended:
-        description: Boolean property which set's the adc as single-ended.
+        description: Whether the sensor is single-ended.
         type: boolean
 
   "^rsense@":
     type: object
-    description:
-      Represents a rsense which is connected to one of the device channels.
-      Rsense are used by thermistors and RTD's.
-
+    description: Sense resistor sensor.
     properties:
       reg:
         minimum: 2
         maximum: 20
 
       adi,sensor-type:
-        description: Identifies the sensor as a rsense.
+        description: Sensor type sense resistor sensors.
         $ref: /schemas/types.yaml#/definitions/uint32
         const: 29
 
       adi,rsense-val-milli-ohms:
-        description:
-          Sets the value of the sense resistor. Look at table 20 of the
-          datasheet for information.
+        description: Value of the sense resistor.
 
     required:
       - adi,rsense-val-milli-ohms
@@ -391,7 +409,7 @@ examples:
         #address-cells = <1>;
         #size-cells = <0>;
 
-        sensor_ltc2983: ltc2983@0 {
+        temp@0 {
                 compatible = "adi,ltc2983";
                 reg = <0>;
 
-- 
2.38.1