[v5,1/9] dt-bindings: thermal: qcom: add adc-thermal monitor bindings

Commit Message

Dmitry Baryshkov Sept. 14, 2020, 3:48 p.m. UTC

Add bindings for thermal monitor, part of Qualcomm PMIC5 chips. It is a
close counterpart of VADC part of those PMICs.

Signed-off-by: Dmitry Baryshkov <[e-mail]>
Reviewed-by: Jonathan Cameron <[e-mail]>
---
 .../bindings/thermal/qcom-spmi-adc-tm5.yaml   | 151 ++++++++++++++++++
 1 file changed, 151 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml

Comments

Rob Herring (Arm) Sept. 22, 2020, 11:40 p.m. UTC | #1

On Mon, Sep 14, 2020 at 06:48:01PM +0300, Dmitry Baryshkov wrote:
> Add bindings for thermal monitor, part of Qualcomm PMIC5 chips. It is a
> close counterpart of VADC part of those PMICs.
> 
> Signed-off-by: Dmitry Baryshkov <[e-mail]>
> Reviewed-by: Jonathan Cameron <[e-mail]>
> ---
>  .../bindings/thermal/qcom-spmi-adc-tm5.yaml   | 151 ++++++++++++++++++
>  1 file changed, 151 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
> 
> diff --git a/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
> new file mode 100644
> index 000000000000..432a65839b89
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
> @@ -0,0 +1,151 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/thermal/qcom-spmi-adc-tm5.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm's SPMI PMIC ADC Thermal Monitoring
> +maintainers:
> +  - Dmitry Baryshkov <[e-mail]>
> +
> +properties:
> +  compatible:
> +    const: qcom,spmi-adc-tm5
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  "#thermal-sensor-cells":
> +    const: 1
> +    description:
> +      Number of cells required to uniquely identify the thermal sensors. Since
> +      we have multiple sensors this is set to 1
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 0
> +
> +  qcom,avg-samples:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: Number of samples to be used for measurement.
> +    enum:
> +      - 1
> +      - 2
> +      - 4
> +      - 8
> +      - 16
> +    default: 1
> +
> +  qcom,decimation:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: This parameter is used to decrease ADC sampling rate.
> +            Quicker measurements can be made by reducing decimation ratio.
> +    enum:
> +      - 250
> +      - 420
> +      - 840
> +    default: 840
> +
> +patternProperties:
> +  "^([-a-z0-9]*)@[0-9]+$":

Less than 10 as unit-addresses are hex?

> +    type: object
> +    description:
> +      Represent one thermal sensor.
> +
> +    properties:
> +      reg:
> +        description: Specify the sensor channel.
> +        maxItems: 1

You need a range of values here.

> +
> +      io-channels:
> +        description:
> +          From common IIO binding. Used to pipe PMIC ADC channel to thermal monitor
> +
> +      qcom,adc-channel:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description: Corresponding ADC channel ID.

Why is this not a cell in io-channels?

> +
> +      qcom,ratiometric:
> +        $ref: /schemas/types.yaml#/definitions/flag
> +        description:
> +          Channel calibration type.
> +          If this property is specified VADC will use the VDD reference
> +          (1.875V) and GND for channel calibration. If property is not found,
> +          channel will be calibrated with 0V and 1.25V reference channels,
> +          also known as absolute calibration.
> +
> +      qcom,hw-settle-time:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description: Time between AMUX getting configured and the ADC starting conversion.

Time values should have a unit suffix. Seems like a commmon ADC 
property...

> +
> +      qcom,pre-scaling:
> +        $ref: /schemas/types.yaml#/definitions/uint32-array
> +        description: Used for scaling the channel input signal before the
> +          signal is fed to VADC. See qcom,spi-vadc specification for the list
> +          of possible values.

I'd rather not. Need the values here to validate a DT.

> +        minItems: 2
> +        maxItems: 2
> +
> +    required:
> +      - reg
> +      - qcom,adc-channel
> +
> +    additionalProperties:
> +      false
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - "#address-cells"
> +  - "#size-cells"
> +  - "#thermal-sensor-cells"
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/iio/qcom,spmi-vadc.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    spmi_bus {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        pm8150b_adc: adc@3100 {
> +            reg = <0x3100>;
> +            compatible = "qcom,spmi-adc5";
> +            #address-cells = <1>;
> +            #size-cells = <0>;
> +            #io-channel-cells = <1>;
> +            io-channel-ranges;
> +
> +            /* Other propreties are omitted */
> +            conn-therm@4f {
> +                reg = <ADC5_AMUX_THM3_100K_PU>;
> +                qcom,ratiometric;
> +                qcom,hw-settle-time = <200>;
> +            };
> +        };
> +
> +        pm8150b_adc_tm: adc-tm@3500 {
> +            compatible = "qcom,spmi-adc-tm5";
> +            reg = <0x3500>;
> +            interrupts = <0x2 0x35 0x0 IRQ_TYPE_EDGE_RISING>;
> +            #thermal-sensor-cells = <1>;
> +            #address-cells = <1>;
> +            #size-cells = <0>;
> +
> +            conn-therm@0 {
> +                reg = <0>;
> +                io-channels = <&pm8150b_adc ADC5_AMUX_THM3_100K_PU>;
> +                qcom,adc-channel = <ADC5_AMUX_THM3_100K_PU>;
> +                qcom,ratiometric;
> +                qcom,hw-settle-time = <200>;
> +            };
> +        };
> +    };
> +...
> -- 
> 2.28.0
>

Dmitry Baryshkov Sept. 23, 2020, 9:07 a.m. UTC | #2

On 23/09/2020 02:40, Rob Herring wrote:
> On Mon, Sep 14, 2020 at 06:48:01PM +0300, Dmitry Baryshkov wrote:
>> Add bindings for thermal monitor, part of Qualcomm PMIC5 chips. It is a
>> close counterpart of VADC part of those PMICs.
>>
>> Signed-off-by: Dmitry Baryshkov <[e-mail]>
>> Reviewed-by: Jonathan Cameron <[e-mail]>
>> ---
>>   .../bindings/thermal/qcom-spmi-adc-tm5.yaml   | 151 ++++++++++++++++++
>>   1 file changed, 151 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
>> new file mode 100644
>> index 000000000000..432a65839b89
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
>> @@ -0,0 +1,151 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/thermal/qcom-spmi-adc-tm5.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Qualcomm's SPMI PMIC ADC Thermal Monitoring
>> +maintainers:
>> +  - Dmitry Baryshkov <[e-mail]>
>> +
>> +properties:
>> +  compatible:
>> +    const: qcom,spmi-adc-tm5
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  interrupts:
>> +    maxItems: 1
>> +
>> +  "#thermal-sensor-cells":
>> +    const: 1
>> +    description:
>> +      Number of cells required to uniquely identify the thermal sensors. Since
>> +      we have multiple sensors this is set to 1
>> +
>> +  "#address-cells":
>> +    const: 1
>> +
>> +  "#size-cells":
>> +    const: 0
>> +
>> +  qcom,avg-samples:
>> +    $ref: /schemas/types.yaml#/definitions/uint32
>> +    description: Number of samples to be used for measurement.
>> +    enum:
>> +      - 1
>> +      - 2
>> +      - 4
>> +      - 8
>> +      - 16
>> +    default: 1
>> +
>> +  qcom,decimation:
>> +    $ref: /schemas/types.yaml#/definitions/uint32
>> +    description: This parameter is used to decrease ADC sampling rate.
>> +            Quicker measurements can be made by reducing decimation ratio.
>> +    enum:
>> +      - 250
>> +      - 420
>> +      - 840
>> +    default: 840
>> +
>> +patternProperties:
>> +  "^([-a-z0-9]*)@[0-9]+$":
> 
> Less than 10 as unit-addresses are hex?

8 channels at max currently. I'll fix to use hex though.

> 
>> +    type: object
>> +    description:
>> +      Represent one thermal sensor.
>> +
>> +    properties:
>> +      reg:
>> +        description: Specify the sensor channel.
>> +        maxItems: 1
> 
> You need a range of values here.

ok.

> 
>> +
>> +      io-channels:
>> +        description:
>> +          From common IIO binding. Used to pipe PMIC ADC channel to thermal monitor
>> +
>> +      qcom,adc-channel:
>> +        $ref: /schemas/types.yaml#/definitions/uint32
>> +        description: Corresponding ADC channel ID.
> 
> Why is this not a cell in io-channels?


Do you mean parsing a cell from io-channels rather than specifying it 
again? Sounds like a good idea.

> 
>> +
>> +      qcom,ratiometric:
>> +        $ref: /schemas/types.yaml#/definitions/flag
>> +        description:
>> +          Channel calibration type.
>> +          If this property is specified VADC will use the VDD reference
>> +          (1.875V) and GND for channel calibration. If property is not found,
>> +          channel will be calibrated with 0V and 1.25V reference channels,
>> +          also known as absolute calibration.
>> +
>> +      qcom,hw-settle-time:
>> +        $ref: /schemas/types.yaml#/definitions/uint32
>> +        description: Time between AMUX getting configured and the ADC starting conversion.
> 
> Time values should have a unit suffix. Seems like a commmon ADC
> property...

Could you please be more specific here? Would you like for me to just 
specify the unit in the description?

> 
>> +
>> +      qcom,pre-scaling:
>> +        $ref: /schemas/types.yaml#/definitions/uint32-array
>> +        description: Used for scaling the channel input signal before the
>> +          signal is fed to VADC. See qcom,spi-vadc specification for the list
>> +          of possible values.
> 
> I'd rather not. Need the values here to validate a DT.

OK

> 
>> +        minItems: 2
>> +        maxItems: 2
>> +
>> +    required:
>> +      - reg
>> +      - qcom,adc-channel
>> +
>> +    additionalProperties:
>> +      false
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - interrupts
>> +  - "#address-cells"
>> +  - "#size-cells"
>> +  - "#thermal-sensor-cells"
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    #include <dt-bindings/iio/qcom,spmi-vadc.h>
>> +    #include <dt-bindings/interrupt-controller/irq.h>
>> +    spmi_bus {
>> +        #address-cells = <1>;
>> +        #size-cells = <0>;
>> +        pm8150b_adc: adc@3100 {
>> +            reg = <0x3100>;
>> +            compatible = "qcom,spmi-adc5";
>> +            #address-cells = <1>;
>> +            #size-cells = <0>;
>> +            #io-channel-cells = <1>;
>> +            io-channel-ranges;
>> +
>> +            /* Other propreties are omitted */
>> +            conn-therm@4f {
>> +                reg = <ADC5_AMUX_THM3_100K_PU>;
>> +                qcom,ratiometric;
>> +                qcom,hw-settle-time = <200>;
>> +            };
>> +        };
>> +
>> +        pm8150b_adc_tm: adc-tm@3500 {
>> +            compatible = "qcom,spmi-adc-tm5";
>> +            reg = <0x3500>;
>> +            interrupts = <0x2 0x35 0x0 IRQ_TYPE_EDGE_RISING>;
>> +            #thermal-sensor-cells = <1>;
>> +            #address-cells = <1>;
>> +            #size-cells = <0>;
>> +
>> +            conn-therm@0 {
>> +                reg = <0>;
>> +                io-channels = <&pm8150b_adc ADC5_AMUX_THM3_100K_PU>;
>> +                qcom,adc-channel = <ADC5_AMUX_THM3_100K_PU>;
>> +                qcom,ratiometric;
>> +                qcom,hw-settle-time = <200>;
>> +            };
>> +        };
>> +    };
>> +...
>> -- 
>> 2.28.0
>>

Rob Herring (Arm) Sept. 23, 2020, 2 p.m. UTC | #3

On Wed, Sep 23, 2020 at 3:07 AM Dmitry Baryshkov
<[e-mail]> wrote:
>
> On 23/09/2020 02:40, Rob Herring wrote:
> > On Mon, Sep 14, 2020 at 06:48:01PM +0300, Dmitry Baryshkov wrote:
> >> Add bindings for thermal monitor, part of Qualcomm PMIC5 chips. It is a
> >> close counterpart of VADC part of those PMICs.
> >>
> >> Signed-off-by: Dmitry Baryshkov <[e-mail]>
> >> Reviewed-by: Jonathan Cameron <[e-mail]>
> >> ---
> >>   .../bindings/thermal/qcom-spmi-adc-tm5.yaml   | 151 ++++++++++++++++++
> >>   1 file changed, 151 insertions(+)
> >>   create mode 100644 Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
> >>
> >> diff --git a/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
> >> new file mode 100644
> >> index 000000000000..432a65839b89
> >> --- /dev/null
> >> +++ b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
> >> @@ -0,0 +1,151 @@
> >> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> >> +%YAML 1.2
> >> +---
> >> +$id: http://devicetree.org/schemas/thermal/qcom-spmi-adc-tm5.yaml#
> >> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> >> +
> >> +title: Qualcomm's SPMI PMIC ADC Thermal Monitoring
> >> +maintainers:
> >> +  - Dmitry Baryshkov <[e-mail]>
> >> +
> >> +properties:
> >> +  compatible:
> >> +    const: qcom,spmi-adc-tm5
> >> +
> >> +  reg:
> >> +    maxItems: 1
> >> +
> >> +  interrupts:
> >> +    maxItems: 1
> >> +
> >> +  "#thermal-sensor-cells":
> >> +    const: 1
> >> +    description:
> >> +      Number of cells required to uniquely identify the thermal sensors. Since
> >> +      we have multiple sensors this is set to 1
> >> +
> >> +  "#address-cells":
> >> +    const: 1
> >> +
> >> +  "#size-cells":
> >> +    const: 0
> >> +
> >> +  qcom,avg-samples:
> >> +    $ref: /schemas/types.yaml#/definitions/uint32
> >> +    description: Number of samples to be used for measurement.
> >> +    enum:
> >> +      - 1
> >> +      - 2
> >> +      - 4
> >> +      - 8
> >> +      - 16
> >> +    default: 1
> >> +
> >> +  qcom,decimation:
> >> +    $ref: /schemas/types.yaml#/definitions/uint32
> >> +    description: This parameter is used to decrease ADC sampling rate.
> >> +            Quicker measurements can be made by reducing decimation ratio.
> >> +    enum:
> >> +      - 250
> >> +      - 420
> >> +      - 840
> >> +    default: 840
> >> +
> >> +patternProperties:
> >> +  "^([-a-z0-9]*)@[0-9]+$":
> >
> > Less than 10 as unit-addresses are hex?
>
> 8 channels at max currently. I'll fix to use hex though.

Then it should be @[0-7]$

> >> +    type: object
> >> +    description:
> >> +      Represent one thermal sensor.
> >> +
> >> +    properties:
> >> +      reg:
> >> +        description: Specify the sensor channel.
> >> +        maxItems: 1
> >
> > You need a range of values here.
>
> ok.
>
> >
> >> +
> >> +      io-channels:
> >> +        description:
> >> +          From common IIO binding. Used to pipe PMIC ADC channel to thermal monitor
> >> +
> >> +      qcom,adc-channel:
> >> +        $ref: /schemas/types.yaml#/definitions/uint32
> >> +        description: Corresponding ADC channel ID.
> >
> > Why is this not a cell in io-channels?
>
>
> Do you mean parsing a cell from io-channels rather than specifying it
> again? Sounds like a good idea.

Yes.

> >> +      qcom,ratiometric:
> >> +        $ref: /schemas/types.yaml#/definitions/flag
> >> +        description:
> >> +          Channel calibration type.
> >> +          If this property is specified VADC will use the VDD reference
> >> +          (1.875V) and GND for channel calibration. If property is not found,
> >> +          channel will be calibrated with 0V and 1.25V reference channels,
> >> +          also known as absolute calibration.
> >> +
> >> +      qcom,hw-settle-time:
> >> +        $ref: /schemas/types.yaml#/definitions/uint32
> >> +        description: Time between AMUX getting configured and the ADC starting conversion.
> >
> > Time values should have a unit suffix. Seems like a commmon ADC
> > property...
>
> Could you please be more specific here? Would you like for me to just
> specify the unit in the description?

More a question for Jonathan I guess as to whether this should be
common or not. Maybe we have something already. Settle or acquisition
time is a common thing for ADCs, right?

Properties with units need a suffix as defined in
.../bindings/property-units.txt.

Rob

Jonathan Cameron Sept. 23, 2020, 3:22 p.m. UTC | #4

On Wed, 23 Sep 2020 08:00:29 -0600
Rob Herring <[e-mail]> wrote:

> On Wed, Sep 23, 2020 at 3:07 AM Dmitry Baryshkov
> <[e-mail]> wrote:
> >
> > On 23/09/2020 02:40, Rob Herring wrote:  
> > > On Mon, Sep 14, 2020 at 06:48:01PM +0300, Dmitry Baryshkov wrote:  
> > >> Add bindings for thermal monitor, part of Qualcomm PMIC5 chips. It is a
> > >> close counterpart of VADC part of those PMICs.
> > >>
> > >> Signed-off-by: Dmitry Baryshkov <[e-mail]>
> > >> Reviewed-by: Jonathan Cameron <[e-mail]>
> > >> ---
> > >>   .../bindings/thermal/qcom-spmi-adc-tm5.yaml   | 151 ++++++++++++++++++
> > >>   1 file changed, 151 insertions(+)
> > >>   create mode 100644 Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
> > >>
> > >> diff --git a/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
> > >> new file mode 100644
> > >> index 000000000000..432a65839b89
> > >> --- /dev/null
> > >> +++ b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
> > >> @@ -0,0 +1,151 @@
> > >> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > >> +%YAML 1.2
> > >> +---
> > >> +$id: http://devicetree.org/schemas/thermal/qcom-spmi-adc-tm5.yaml#
> > >> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > >> +
> > >> +title: Qualcomm's SPMI PMIC ADC Thermal Monitoring
> > >> +maintainers:
> > >> +  - Dmitry Baryshkov <[e-mail]>
> > >> +
> > >> +properties:
> > >> +  compatible:
> > >> +    const: qcom,spmi-adc-tm5
> > >> +
> > >> +  reg:
> > >> +    maxItems: 1
> > >> +
> > >> +  interrupts:
> > >> +    maxItems: 1
> > >> +
> > >> +  "#thermal-sensor-cells":
> > >> +    const: 1
> > >> +    description:
> > >> +      Number of cells required to uniquely identify the thermal sensors. Since
> > >> +      we have multiple sensors this is set to 1
> > >> +
> > >> +  "#address-cells":
> > >> +    const: 1
> > >> +
> > >> +  "#size-cells":
> > >> +    const: 0
> > >> +
> > >> +  qcom,avg-samples:
> > >> +    $ref: /schemas/types.yaml#/definitions/uint32
> > >> +    description: Number of samples to be used for measurement.
> > >> +    enum:
> > >> +      - 1
> > >> +      - 2
> > >> +      - 4
> > >> +      - 8
> > >> +      - 16
> > >> +    default: 1
> > >> +
> > >> +  qcom,decimation:
> > >> +    $ref: /schemas/types.yaml#/definitions/uint32
> > >> +    description: This parameter is used to decrease ADC sampling rate.
> > >> +            Quicker measurements can be made by reducing decimation ratio.
> > >> +    enum:
> > >> +      - 250
> > >> +      - 420
> > >> +      - 840
> > >> +    default: 840
> > >> +
> > >> +patternProperties:
> > >> +  "^([-a-z0-9]*)@[0-9]+$":  
> > >
> > > Less than 10 as unit-addresses are hex?  
> >
> > 8 channels at max currently. I'll fix to use hex though.  
> 
> Then it should be @[0-7]$
> 
> > >> +    type: object
> > >> +    description:
> > >> +      Represent one thermal sensor.
> > >> +
> > >> +    properties:
> > >> +      reg:
> > >> +        description: Specify the sensor channel.
> > >> +        maxItems: 1  
> > >
> > > You need a range of values here.  
> >
> > ok.
> >  
> > >  
> > >> +
> > >> +      io-channels:
> > >> +        description:
> > >> +          From common IIO binding. Used to pipe PMIC ADC channel to thermal monitor
> > >> +
> > >> +      qcom,adc-channel:
> > >> +        $ref: /schemas/types.yaml#/definitions/uint32
> > >> +        description: Corresponding ADC channel ID.  
> > >
> > > Why is this not a cell in io-channels?  
> >
> >
> > Do you mean parsing a cell from io-channels rather than specifying it
> > again? Sounds like a good idea.  
> 
> Yes.
> 
> > >> +      qcom,ratiometric:
> > >> +        $ref: /schemas/types.yaml#/definitions/flag
> > >> +        description:
> > >> +          Channel calibration type.
> > >> +          If this property is specified VADC will use the VDD reference
> > >> +          (1.875V) and GND for channel calibration. If property is not found,
> > >> +          channel will be calibrated with 0V and 1.25V reference channels,
> > >> +          also known as absolute calibration.
> > >> +
> > >> +      qcom,hw-settle-time:
> > >> +        $ref: /schemas/types.yaml#/definitions/uint32
> > >> +        description: Time between AMUX getting configured and the ADC starting conversion.  
> > >
> > > Time values should have a unit suffix. Seems like a commmon ADC
> > > property...  
> >
> > Could you please be more specific here? Would you like for me to just
> > specify the unit in the description?  
> 
> More a question for Jonathan I guess as to whether this should be
> common or not. Maybe we have something already. Settle or acquisition
> time is a common thing for ADCs, right?

It's not common in my experience, but not unheard of.
Only cases currently supporting controlling it explicitly in the
kernel that I can spot, are currently all qcom parts
(I'd guess they are all using the same IP underneath)

I think it is usually it's a case of building your analog
circuitry to match the spec of your ADC / MUX rather than
relaxing that spec by adding a delay.

It's a property with obvious enough meaning though that I
wouldn't have a problem with it being a generic property even
it is one that doesn't actually get used much.

> 
> Properties with units need a suffix as defined in
> .../bindings/property-units.txt.

We have a bunch of legacy bindings that don't have units but
all new ones certainly should!

Thanks,

Jonathan

> 
> Rob

Patch

diff --git a/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
new file mode 100644
index 000000000000..432a65839b89
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/qcom-spmi-adc-tm5.yaml
@@ -0,0 +1,151 @@ 
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/thermal/qcom-spmi-adc-tm5.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm's SPMI PMIC ADC Thermal Monitoring
+maintainers:
+  - Dmitry Baryshkov <[e-mail]>
+
+properties:
+  compatible:
+    const: qcom,spmi-adc-tm5
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  "#thermal-sensor-cells":
+    const: 1
+    description:
+      Number of cells required to uniquely identify the thermal sensors. Since
+      we have multiple sensors this is set to 1
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+  qcom,avg-samples:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: Number of samples to be used for measurement.
+    enum:
+      - 1
+      - 2
+      - 4
+      - 8
+      - 16
+    default: 1
+
+  qcom,decimation:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: This parameter is used to decrease ADC sampling rate.
+            Quicker measurements can be made by reducing decimation ratio.
+    enum:
+      - 250
+      - 420
+      - 840
+    default: 840
+
+patternProperties:
+  "^([-a-z0-9]*)@[0-9]+$":
+    type: object
+    description:
+      Represent one thermal sensor.
+
+    properties:
+      reg:
+        description: Specify the sensor channel.
+        maxItems: 1
+
+      io-channels:
+        description:
+          From common IIO binding. Used to pipe PMIC ADC channel to thermal monitor
+
+      qcom,adc-channel:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        description: Corresponding ADC channel ID.
+
+      qcom,ratiometric:
+        $ref: /schemas/types.yaml#/definitions/flag
+        description:
+          Channel calibration type.
+          If this property is specified VADC will use the VDD reference
+          (1.875V) and GND for channel calibration. If property is not found,
+          channel will be calibrated with 0V and 1.25V reference channels,
+          also known as absolute calibration.
+
+      qcom,hw-settle-time:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        description: Time between AMUX getting configured and the ADC starting conversion.
+
+      qcom,pre-scaling:
+        $ref: /schemas/types.yaml#/definitions/uint32-array
+        description: Used for scaling the channel input signal before the
+          signal is fed to VADC. See qcom,spi-vadc specification for the list
+          of possible values.
+        minItems: 2
+        maxItems: 2
+
+    required:
+      - reg
+      - qcom,adc-channel
+
+    additionalProperties:
+      false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - "#address-cells"
+  - "#size-cells"
+  - "#thermal-sensor-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/iio/qcom,spmi-vadc.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+    spmi_bus {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        pm8150b_adc: adc@3100 {
+            reg = <0x3100>;
+            compatible = "qcom,spmi-adc5";
+            #address-cells = <1>;
+            #size-cells = <0>;
+            #io-channel-cells = <1>;
+            io-channel-ranges;
+
+            /* Other propreties are omitted */
+            conn-therm@4f {
+                reg = <ADC5_AMUX_THM3_100K_PU>;
+                qcom,ratiometric;
+                qcom,hw-settle-time = <200>;
+            };
+        };
+
+        pm8150b_adc_tm: adc-tm@3500 {
+            compatible = "qcom,spmi-adc-tm5";
+            reg = <0x3500>;
+            interrupts = <0x2 0x35 0x0 IRQ_TYPE_EDGE_RISING>;
+            #thermal-sensor-cells = <1>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            conn-therm@0 {
+                reg = <0>;
+                io-channels = <&pm8150b_adc ADC5_AMUX_THM3_100K_PU>;
+                qcom,adc-channel = <ADC5_AMUX_THM3_100K_PU>;
+                qcom,ratiometric;
+                qcom,hw-settle-time = <200>;
+            };
+        };
+    };
+...