Re: [PATCH 2/3] iio: adc: Add PMIC7 ADC bindings

From: Jonathan Cameron <jic23@kernel.org>
To: Jishnu Prakash <jprakash@codeaurora.org>
Cc: agross@kernel.org, bjorn.andersson@linaro.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	mka@chromium.org, linus.walleij@linaro.org, sboyd@codeaurora.org,
	Jonathan.Cameron@huawei.com, smohanad@codeaurora.org,
	kgunda@codeaurora.org, aghayal@codeaurora.org,
	Hartmut Knaack <knaack.h@gmx.de>,
	Lars-Peter Clausen <lars@metafoo.de>,
	Peter Meerwald-Stadler <pmeerw@pmeerw.net>,
	Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	linux-iio@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	linux-arm-msm-owner@vger.kernel.org
Subject: Re: [PATCH 2/3] iio: adc: Add PMIC7 ADC bindings
Date: Sat, 28 Mar 2020 16:54:10 +0000	[thread overview]
Message-ID: <20200328165410.7db48818@archlinux> (raw)
In-Reply-To: <1585064650-16235-3-git-send-email-jprakash@codeaurora.org>

On Tue, 24 Mar 2020 21:14:09 +0530
Jishnu Prakash <jprakash@codeaurora.org> wrote:

> Add documentation for PMIC7 ADC peripheral. For PMIC7 ADC, all SW
> communication to ADC goes through PMK8350, which communicates with
> other PMICs through PBS.
> 
> Signed-off-by: Jishnu Prakash <jprakash@codeaurora.org>
> ---
>  .../bindings/iio/adc/qcom,spmi-vadc.yaml           | 28 ++++++++++++++++------
>  1 file changed, 21 insertions(+), 7 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.yaml b/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.yaml
> index 72db14c..20f010c 100644
> --- a/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.yaml
> +++ b/Documentation/devicetree/bindings/iio/adc/qcom,spmi-vadc.yaml
> @@ -13,7 +13,7 @@ maintainers:
>  description: |
>    SPMI PMIC voltage ADC (VADC) provides interface to clients to read
>    voltage. The VADC is a 15-bit sigma-delta ADC.
> -  SPMI PMIC5 voltage ADC (ADC) provides interface to clients to read
> +  SPMI PMIC5/PMIC7 voltage ADC (ADC) provides interface to clients to read
>    voltage. The VADC is a 16-bit sigma-delta ADC.
>  
>  properties:
> @@ -23,6 +23,7 @@ properties:
>        - qcom,spmi-adc5
>        - qcom,spmi-adc-rev2
>        - qcom,pms405-adc
> +      - qcom,spmi-adc7
>  
>    reg:
>      description: VADC base address in the SPMI PMIC register map
> @@ -65,6 +66,8 @@ patternProperties:
>          description: |
>            ADC channel number.
>            See include/dt-bindings/iio/qcom,spmi-vadc.h
> +          For PMIC7 ADC, the channel numbers are specified separately per PMIC
> +          in the PMIC-specific files in include/dt-bindings/iio/.

That makes me thing we really should have separate compatibles.  The
parts clearly have differences, even if we haven't needed to use them
explicitly as yet.

>  
>        label:
>          description: |
> @@ -72,7 +75,7 @@ patternProperties:
>              For thermistor inputs connected to generic AMUX or GPIO inputs
>              these can vary across platform for the same pins. Hence select
>              the platform schematics name for this channel. It is required
> -            for "qcom,spmi-adc5" and "qcom,spmi-adc-rev2".
> +            for "qcom,spmi-adc5", "qcom,spmi-adc7" and "qcom,spmi-adc-rev2".
>          allOf:
>            - $ref: /schemas/types.yaml#/definitions/string
>  
> @@ -85,6 +88,8 @@ patternProperties:
>                of 512 will be used.
>              - For compatible property "qcom,spmi-adc5", valid values are 250, 420
>                and 840. If property is not found, default value of 840 is used.
> +            - For compatible property "qcom,spmi-adc7", valid values are 85, 340
> +              and 1360. If property is not found, default value of 1360 is used.
>              - For compatible property "qcom,spmi-adc-rev2", valid values are 256,
>                512 and 1024. If property is not present, default value is 1024.
>          allOf:
> @@ -109,11 +114,11 @@ patternProperties:
>                channel calibration. If property is not found, channel will be
>                calibrated with 0.625V and 1.25V reference channels, also
>                known as absolute calibration.
> -            - For compatible property "qcom,spmi-adc5" and "qcom,spmi-adc-rev2",
> -              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.
> +            - For compatible property "qcom,spmi-adc5", "qcom,spmi-adc7" and
> +              "qcom,spmi-adc-rev2", 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.
>          type: boolean
>  
>        qcom,hw-settle-time:
> @@ -135,6 +140,12 @@ patternProperties:
>                Certain controller digital versions have valid values of
>                15, 100, 200, 300, 400, 500, 600, 700, 1, 2, 4, 8, 16, 32, 64, 128 ms
>                If property is not found, channel will use 15us.
> +            - For compatible property "qcom,spmi-adc7", delay = 15us for
> +              value 0, 100us * (value) for values < 8, 1ms for value 8
> +              and 2ms * (value - 8) otherwise.
> +              Valid values are: 15, 100, 200, 300, 400, 500, 600, 700, 1000, 2000,
> +              4000, 8000, 16000, 32000, 64000, 128000 us.
> +              If property is not found, channel will use 15us.
>          allOf:
>            - $ref: /schemas/types.yaml#/definitions/uint32
>  
> @@ -147,6 +158,9 @@ patternProperties:
>              - For compatible property "qcom,spmi-vadc", valid values
>                are: 1, 2, 4, 8, 16, 32, 64, 128, 256, 512
>                If property is not found, 1 sample will be used.
> +            - For compatible property "qcom,spmi-adc5", "qcom,spmi-adc7"
> +              and "qcom,spmi-adc-rev2", valid values are: 1, 2, 4, 8, 16.
> +              If property is not found, 1 sample will be used.
>          allOf:
>            - $ref: /schemas/types.yaml#/definitions/uint32
>  