| Message ID | 20201011170749.243680-21-jic23@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | dt-bindings:iio: Another set of yaml conversions. | expand |
Hi Jonathan, On Sun, 11 Oct 2020 18:07:40 +0100 Jonathan Cameron <jic23@kernel.org> wrote: > From: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > I'm not sure vdd-supply absolutely has to be provided if vref-supply > is, but as the previous binding docs stated it was required it seems > reasonable to leave it as such. Good catch. Vdd is useless on MCP4726 if Vref is specified. The driver requires Vdd... How to proceed there? Thanks, Tomas > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > Cc: Tomas Novotny <tomas@novotny.cz> > --- > .../devicetree/bindings/iio/dac/mcp4725.txt | 35 --------- > .../bindings/iio/dac/microchip,mcp4725.yaml | 71 +++++++++++++++++++ > 2 files changed, 71 insertions(+), 35 deletions(-) > > diff --git a/Documentation/devicetree/bindings/iio/dac/mcp4725.txt b/Documentation/devicetree/bindings/iio/dac/mcp4725.txt > deleted file mode 100644 > index 1bc6c093fbfe..000000000000 > --- a/Documentation/devicetree/bindings/iio/dac/mcp4725.txt > +++ /dev/null > @@ -1,35 +0,0 @@ > -Microchip mcp4725 and mcp4726 DAC device driver > - > -Required properties: > - - compatible: Must be "microchip,mcp4725" or "microchip,mcp4726" > - - reg: Should contain the DAC I2C address > - - vdd-supply: Phandle to the Vdd power supply. This supply is used as a > - voltage reference on mcp4725. It is used as a voltage reference on > - mcp4726 if there is no vref-supply specified. > - > -Optional properties (valid only for mcp4726): > - - vref-supply: Optional phandle to the Vref power supply. Vref pin is > - used as a voltage reference when this supply is specified. > - - microchip,vref-buffered: Boolean to enable buffering of the external > - Vref pin. This boolean is not valid without the vref-supply. Quoting > - the datasheet: This is offered in cases where the reference voltage > - does not have the current capability not to drop its voltage when > - connected to the internal resistor ladder circuit. > - > -Examples: > - > - /* simple mcp4725 */ > - mcp4725@60 { > - compatible = "microchip,mcp4725"; > - reg = <0x60>; > - vdd-supply = <&vdac_vdd>; > - }; > - > - /* mcp4726 with the buffered external reference voltage */ > - mcp4726@60 { > - compatible = "microchip,mcp4726"; > - reg = <0x60>; > - vdd-supply = <&vdac_vdd>; > - vref-supply = <&vdac_vref>; > - microchip,vref-buffered; > - }; > diff --git a/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml > new file mode 100644 > index 000000000000..271998610ceb > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml > @@ -0,0 +1,71 @@ > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/iio/dac/microchip,mcp4725.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Microchip mcp4725 and mcp4726 DAC > + > +maintainers: > + - Tomas Novotny <tomas@novotny.cz> > + > +properties: > + compatible: > + enum: > + - microchip,mcp4725 > + - microchip,mcp4726 > + > + reg: > + maxItems: 1 > + > + vdd-supply: > + description: | > + Provides both power and acts as the reference supply on the mcp4725. > + For the mcp4726 it will be used as the reference voltage if vref-supply > + is not provided. > + > + vref-supply: > + description: > + Vref pin is used as a voltage reference when this supply is specified. > + > + microchip,vref-buffered: > + type: boolean > + description: | > + Enable buffering of the external Vref pin. This boolean is not valid > + without the vref-supply. Quoting the datasheet: This is offered in > + cases where the reference voltage does not have the current > + capability not to drop its voltage when connected to the internal > + resistor ladder circuit. > + > +allOf: > + - if: > + not: > + properties: > + compatible: > + contains: > + const: microchip,mcp4726 > + then: > + properties: > + vref-supply: false > + microchip,vref-buffered: false > + > +required: > + - compatible > + - reg > + - vdd-supply > + > +additionalProperties: false > + > +examples: > + - | > + i2c { > + #address-cells = <1>; > + #size-cells = <0>; > + > + mcp4725@60 { > + compatible = "microchip,mcp4725"; > + reg = <0x60>; > + vdd-supply = <&vdac_vdd>; > + }; > + }; > +...
On Mon, 12 Oct 2020 16:02:30 +0200 Tomas Novotny <tomas@novotny.cz> wrote: > Hi Jonathan, > > On Sun, 11 Oct 2020 18:07:40 +0100 > Jonathan Cameron <jic23@kernel.org> wrote: > > > From: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > > > I'm not sure vdd-supply absolutely has to be provided if vref-supply > > is, but as the previous binding docs stated it was required it seems > > reasonable to leave it as such. > > Good catch. Vdd is useless on MCP4726 if Vref is specified. The driver > requires Vdd... The driver will get the regulator but as it's not via an optional call it the regulator core will provide a stub regulator. If the ref regulator is present, all that will happen with vdd is a regulator_enable() call which is fine with a stub regulator (it's a noop). So we should be good to update the binding to specify the requirement. Perhaps it's one to do as a follow up patch? Given any existing DT must be providing that regulator, there is no rush for us to fix it :) > > How to proceed there? > > Thanks, > > Tomas > > > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > Cc: Tomas Novotny <tomas@novotny.cz> > > --- > > .../devicetree/bindings/iio/dac/mcp4725.txt | 35 --------- > > .../bindings/iio/dac/microchip,mcp4725.yaml | 71 +++++++++++++++++++ > > 2 files changed, 71 insertions(+), 35 deletions(-) > > > > diff --git a/Documentation/devicetree/bindings/iio/dac/mcp4725.txt b/Documentation/devicetree/bindings/iio/dac/mcp4725.txt > > deleted file mode 100644 > > index 1bc6c093fbfe..000000000000 > > --- a/Documentation/devicetree/bindings/iio/dac/mcp4725.txt > > +++ /dev/null > > @@ -1,35 +0,0 @@ > > -Microchip mcp4725 and mcp4726 DAC device driver > > - > > -Required properties: > > - - compatible: Must be "microchip,mcp4725" or "microchip,mcp4726" > > - - reg: Should contain the DAC I2C address > > - - vdd-supply: Phandle to the Vdd power supply. This supply is used as a > > - voltage reference on mcp4725. It is used as a voltage reference on > > - mcp4726 if there is no vref-supply specified. > > - > > -Optional properties (valid only for mcp4726): > > - - vref-supply: Optional phandle to the Vref power supply. Vref pin is > > - used as a voltage reference when this supply is specified. > > - - microchip,vref-buffered: Boolean to enable buffering of the external > > - Vref pin. This boolean is not valid without the vref-supply. Quoting > > - the datasheet: This is offered in cases where the reference voltage > > - does not have the current capability not to drop its voltage when > > - connected to the internal resistor ladder circuit. > > - > > -Examples: > > - > > - /* simple mcp4725 */ > > - mcp4725@60 { > > - compatible = "microchip,mcp4725"; > > - reg = <0x60>; > > - vdd-supply = <&vdac_vdd>; > > - }; > > - > > - /* mcp4726 with the buffered external reference voltage */ > > - mcp4726@60 { > > - compatible = "microchip,mcp4726"; > > - reg = <0x60>; > > - vdd-supply = <&vdac_vdd>; > > - vref-supply = <&vdac_vref>; > > - microchip,vref-buffered; > > - }; > > diff --git a/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml > > new file mode 100644 > > index 000000000000..271998610ceb > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml > > @@ -0,0 +1,71 @@ > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > > +%YAML 1.2 > > +--- > > +$id: http://devicetree.org/schemas/iio/dac/microchip,mcp4725.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: Microchip mcp4725 and mcp4726 DAC > > + > > +maintainers: > > + - Tomas Novotny <tomas@novotny.cz> > > + > > +properties: > > + compatible: > > + enum: > > + - microchip,mcp4725 > > + - microchip,mcp4726 > > + > > + reg: > > + maxItems: 1 > > + > > + vdd-supply: > > + description: | > > + Provides both power and acts as the reference supply on the mcp4725. > > + For the mcp4726 it will be used as the reference voltage if vref-supply > > + is not provided. > > + > > + vref-supply: > > + description: > > + Vref pin is used as a voltage reference when this supply is specified. > > + > > + microchip,vref-buffered: > > + type: boolean > > + description: | > > + Enable buffering of the external Vref pin. This boolean is not valid > > + without the vref-supply. Quoting the datasheet: This is offered in > > + cases where the reference voltage does not have the current > > + capability not to drop its voltage when connected to the internal > > + resistor ladder circuit. > > + > > +allOf: > > + - if: > > + not: > > + properties: > > + compatible: > > + contains: > > + const: microchip,mcp4726 > > + then: > > + properties: > > + vref-supply: false > > + microchip,vref-buffered: false > > + > > +required: > > + - compatible > > + - reg > > + - vdd-supply > > + > > +additionalProperties: false > > + > > +examples: > > + - | > > + i2c { > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + mcp4725@60 { > > + compatible = "microchip,mcp4725"; > > + reg = <0x60>; > > + vdd-supply = <&vdac_vdd>; > > + }; > > + }; > > +...
Hi Jonathan, On Mon, 12 Oct 2020 15:39:23 +0100 Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote: > On Mon, 12 Oct 2020 16:02:30 +0200 > Tomas Novotny <tomas@novotny.cz> wrote: > > > Hi Jonathan, > > > > On Sun, 11 Oct 2020 18:07:40 +0100 > > Jonathan Cameron <jic23@kernel.org> wrote: > > > > > From: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > > > > > I'm not sure vdd-supply absolutely has to be provided if vref-supply > > > is, but as the previous binding docs stated it was required it seems > > > reasonable to leave it as such. > > > > Good catch. Vdd is useless on MCP4726 if Vref is specified. The driver > > requires Vdd... > > The driver will get the regulator but as it's not via an optional > call it the regulator core will provide a stub regulator. > If the ref regulator is present, all that will happen with vdd is > a regulator_enable() call which is fine with a stub regulator (it's > a noop). So we should be good to update the binding to specify > the requirement. Perhaps it's one to do as a follow up patch? > Given any existing DT must be providing that regulator, there is > no rush for us to fix it :) ok, I see, I will handle with a follow up patch when this will be merged. Thanks, Tomas > > How to proceed there? > > > > Thanks, > > > > Tomas > > > > > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > > Cc: Tomas Novotny <tomas@novotny.cz> > > > --- > > > .../devicetree/bindings/iio/dac/mcp4725.txt | 35 --------- > > > .../bindings/iio/dac/microchip,mcp4725.yaml | 71 +++++++++++++++++++ > > > 2 files changed, 71 insertions(+), 35 deletions(-) > > > > > > diff --git a/Documentation/devicetree/bindings/iio/dac/mcp4725.txt b/Documentation/devicetree/bindings/iio/dac/mcp4725.txt > > > deleted file mode 100644 > > > index 1bc6c093fbfe..000000000000 > > > --- a/Documentation/devicetree/bindings/iio/dac/mcp4725.txt > > > +++ /dev/null > > > @@ -1,35 +0,0 @@ > > > -Microchip mcp4725 and mcp4726 DAC device driver > > > - > > > -Required properties: > > > - - compatible: Must be "microchip,mcp4725" or "microchip,mcp4726" > > > - - reg: Should contain the DAC I2C address > > > - - vdd-supply: Phandle to the Vdd power supply. This supply is used as a > > > - voltage reference on mcp4725. It is used as a voltage reference on > > > - mcp4726 if there is no vref-supply specified. > > > - > > > -Optional properties (valid only for mcp4726): > > > - - vref-supply: Optional phandle to the Vref power supply. Vref pin is > > > - used as a voltage reference when this supply is specified. > > > - - microchip,vref-buffered: Boolean to enable buffering of the external > > > - Vref pin. This boolean is not valid without the vref-supply. Quoting > > > - the datasheet: This is offered in cases where the reference voltage > > > - does not have the current capability not to drop its voltage when > > > - connected to the internal resistor ladder circuit. > > > - > > > -Examples: > > > - > > > - /* simple mcp4725 */ > > > - mcp4725@60 { > > > - compatible = "microchip,mcp4725"; > > > - reg = <0x60>; > > > - vdd-supply = <&vdac_vdd>; > > > - }; > > > - > > > - /* mcp4726 with the buffered external reference voltage */ > > > - mcp4726@60 { > > > - compatible = "microchip,mcp4726"; > > > - reg = <0x60>; > > > - vdd-supply = <&vdac_vdd>; > > > - vref-supply = <&vdac_vref>; > > > - microchip,vref-buffered; > > > - }; > > > diff --git a/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml > > > new file mode 100644 > > > index 000000000000..271998610ceb > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml > > > @@ -0,0 +1,71 @@ > > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > > > +%YAML 1.2 > > > +--- > > > +$id: http://devicetree.org/schemas/iio/dac/microchip,mcp4725.yaml# > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > + > > > +title: Microchip mcp4725 and mcp4726 DAC > > > + > > > +maintainers: > > > + - Tomas Novotny <tomas@novotny.cz> > > > + > > > +properties: > > > + compatible: > > > + enum: > > > + - microchip,mcp4725 > > > + - microchip,mcp4726 > > > + > > > + reg: > > > + maxItems: 1 > > > + > > > + vdd-supply: > > > + description: | > > > + Provides both power and acts as the reference supply on the mcp4725. > > > + For the mcp4726 it will be used as the reference voltage if vref-supply > > > + is not provided. > > > + > > > + vref-supply: > > > + description: > > > + Vref pin is used as a voltage reference when this supply is specified. > > > + > > > + microchip,vref-buffered: > > > + type: boolean > > > + description: | > > > + Enable buffering of the external Vref pin. This boolean is not valid > > > + without the vref-supply. Quoting the datasheet: This is offered in > > > + cases where the reference voltage does not have the current > > > + capability not to drop its voltage when connected to the internal > > > + resistor ladder circuit. > > > + > > > +allOf: > > > + - if: > > > + not: > > > + properties: > > > + compatible: > > > + contains: > > > + const: microchip,mcp4726 > > > + then: > > > + properties: > > > + vref-supply: false > > > + microchip,vref-buffered: false > > > + > > > +required: > > > + - compatible > > > + - reg > > > + - vdd-supply > > > + > > > +additionalProperties: false > > > + > > > +examples: > > > + - | > > > + i2c { > > > + #address-cells = <1>; > > > + #size-cells = <0>; > > > + > > > + mcp4725@60 { > > > + compatible = "microchip,mcp4725"; > > > + reg = <0x60>; > > > + vdd-supply = <&vdac_vdd>; > > > + }; > > > + }; > > > +... > >
diff --git a/Documentation/devicetree/bindings/iio/dac/mcp4725.txt b/Documentation/devicetree/bindings/iio/dac/mcp4725.txt deleted file mode 100644 index 1bc6c093fbfe..000000000000 --- a/Documentation/devicetree/bindings/iio/dac/mcp4725.txt +++ /dev/null @@ -1,35 +0,0 @@ -Microchip mcp4725 and mcp4726 DAC device driver - -Required properties: - - compatible: Must be "microchip,mcp4725" or "microchip,mcp4726" - - reg: Should contain the DAC I2C address - - vdd-supply: Phandle to the Vdd power supply. This supply is used as a - voltage reference on mcp4725. It is used as a voltage reference on - mcp4726 if there is no vref-supply specified. - -Optional properties (valid only for mcp4726): - - vref-supply: Optional phandle to the Vref power supply. Vref pin is - used as a voltage reference when this supply is specified. - - microchip,vref-buffered: Boolean to enable buffering of the external - Vref pin. This boolean is not valid without the vref-supply. Quoting - the datasheet: This is offered in cases where the reference voltage - does not have the current capability not to drop its voltage when - connected to the internal resistor ladder circuit. - -Examples: - - /* simple mcp4725 */ - mcp4725@60 { - compatible = "microchip,mcp4725"; - reg = <0x60>; - vdd-supply = <&vdac_vdd>; - }; - - /* mcp4726 with the buffered external reference voltage */ - mcp4726@60 { - compatible = "microchip,mcp4726"; - reg = <0x60>; - vdd-supply = <&vdac_vdd>; - vref-supply = <&vdac_vref>; - microchip,vref-buffered; - }; diff --git a/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml new file mode 100644 index 000000000000..271998610ceb --- /dev/null +++ b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4725.yaml @@ -0,0 +1,71 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/dac/microchip,mcp4725.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Microchip mcp4725 and mcp4726 DAC + +maintainers: + - Tomas Novotny <tomas@novotny.cz> + +properties: + compatible: + enum: + - microchip,mcp4725 + - microchip,mcp4726 + + reg: + maxItems: 1 + + vdd-supply: + description: | + Provides both power and acts as the reference supply on the mcp4725. + For the mcp4726 it will be used as the reference voltage if vref-supply + is not provided. + + vref-supply: + description: + Vref pin is used as a voltage reference when this supply is specified. + + microchip,vref-buffered: + type: boolean + description: | + Enable buffering of the external Vref pin. This boolean is not valid + without the vref-supply. Quoting the datasheet: This is offered in + cases where the reference voltage does not have the current + capability not to drop its voltage when connected to the internal + resistor ladder circuit. + +allOf: + - if: + not: + properties: + compatible: + contains: + const: microchip,mcp4726 + then: + properties: + vref-supply: false + microchip,vref-buffered: false + +required: + - compatible + - reg + - vdd-supply + +additionalProperties: false + +examples: + - | + i2c { + #address-cells = <1>; + #size-cells = <0>; + + mcp4725@60 { + compatible = "microchip,mcp4725"; + reg = <0x60>; + vdd-supply = <&vdac_vdd>; + }; + }; +...