| Message ID | 20240619064904.73832-4-kimseer.paller@analog.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | Add driver for LTC2664 and LTC2672 | expand |
On Wed, Jun 19, 2024 at 02:49:02PM +0800, Kim Seer Paller wrote: > Add documentation for ltc2664. > > Co-developed-by: Michael Hennerich <michael.hennerich@analog.com> > Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> > Signed-off-by: Kim Seer Paller <kimseer.paller@analog.com> > --- > .../bindings/iio/dac/adi,ltc2664.yaml | 167 ++++++++++++++++++ > MAINTAINERS | 8 + > 2 files changed, 175 insertions(+) > create mode 100644 Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > new file mode 100644 > index 000000000000..be37700e3b1f > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > @@ -0,0 +1,167 @@ > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/iio/dac/adi,ltc2664.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Analog Devices LTC2664 DAC > + > +maintainers: > + - Michael Hennerich <michael.hennerich@analog.com> > + - Kim Seer Paller <kimseer.paller@analog.com> > + > +description: | > + Analog Devices LTC2664 4 channel, 12-/16-Bit, +-10V DAC > + https://www.analog.com/media/en/technical-documentation/data-sheets/2664fa.pdf > + > +properties: > + compatible: > + enum: > + - adi,ltc2664 > + > + reg: > + maxItems: 1 > + > + spi-max-frequency: > + maximum: 50000000 > + > + vcc-supply: > + description: Analog Supply Voltage Input. > + > + v-pos-supply: > + description: Positive Supply Voltage Input. > + > + v-neg-supply: > + description: Negative Supply Voltage Input. > + > + iovcc-supply: > + description: Digital Input/Output Supply Voltage. > + > + ref-supply: > + description: > + Reference Input/Output. The voltage at the REF pin sets the full-scale > + range of all channels. If not provided the internal reference is used and > + also provided on the VREF pin. > + > + reset-gpios: > + description: > + Active-low Asynchronous Clear Input. A logic low at this level-triggered > + input clears the part to the reset code and range determined by the > + hardwired option chosen using the MSPAN pins. The control registers are > + cleared to zero. > + maxItems: 1 > + > + adi,manual-span-operation-config: > + description: > + This property must mimic the MSPAN pin configurations. By tying the MSPAN > + pins (MSP2, MSP1 and MSP0) to GND and/or VCC, any output range can be > + hardware-configured with different mid-scale or zero-scale reset options. > + The hardware configuration is latched during power on reset for proper > + operation. > + 0 - MPS2=GND, MPS1=GND, MSP0=GND (+-10V, reset to 0V) > + 1 - MPS2=GND, MPS1=GND, MSP0=VCC (+-5V, reset to 0V) > + 2 - MPS2=GND, MPS1=VCC, MSP0=GND (+-2.5V, reset to 0V) > + 3 - MPS2=GND, MPS1=VCC, MSP0=VCC (0V to 10, reset to 0V) > + 4 - MPS2=VCC, MPS1=GND, MSP0=GND (0V to 10V, reset to 5V) > + 5 - MPS2=VCC, MPS1=GND, MSP0=VCC (0V to 5V, reset to 0V) > + 6 - MPS2=VCC, MPS1=VCC, MSP0=GND (0V to 5V, reset to 2.5V) > + 7 - MPS2=VCC, MPS1=VCC, MSP0=VCC (0V to 5V, reset to 0V, enables SoftSpan) > + $ref: /schemas/types.yaml#/definitions/uint32 > + enum: [0, 1, 2, 3, 4, 5, 6, 7] Can you explain why this property is required, when below there's one that sets the ranges in microvolts? Isn't the only new information that this provides the reset values (in a few cases that it is not 0). What am I missing? > + default: 7 > + > + io-channels: > + description: > + ADC channel to monitor voltages and temperature at the MUXOUT pin. > + maxItems: 1 > + > + '#address-cells': > + const: 1 > + > + '#size-cells': > + const: 0 > + > +patternProperties: > + "^channel@[0-3]$": > + type: object > + additionalProperties: false > + > + properties: > + reg: > + description: The channel number representing the DAC output channel. > + maximum: 3 > + > + adi,toggle-mode: > + description: > + Set the channel as a toggle enabled channel. Toggle operation enables > + fast switching of a DAC output between two different DAC codes without > + any SPI transaction. > + type: boolean > + > + adi,output-range-microvolt: > + description: Specify the channel output full scale range. > + oneOf: > + - items: > + - const: 0 > + - enum: [5000000, 10000000] > + - items: > + - const: -5000000 > + - const: 5000000 > + - items: > + - const: -10000000 > + - const: 10000000 > + - items: > + - const: -2500000 > + - const: 2500000 > + > + required: > + - reg > + - adi,output-range-microvolt > + > +required: > + - compatible > + - reg > + - spi-max-frequency > + - vcc-supply > + - iovcc-supply > + - v-pos-supply > + - v-neg-supply > + > +allOf: > + - $ref: /schemas/spi/spi-peripheral-props.yaml# > + > +additionalProperties: false > + > +examples: > + - | > + spi { > + #address-cells = <1>; > + #size-cells = <0>; > + dac@0 { > + compatible = "adi,ltc2664"; > + reg = <0>; > + spi-max-frequency = <10000000>; > + > + vcc-supply = <&vcc>; > + iovcc-supply = <&vcc>; > + ref-supply = <&vref>; > + v-pos-supply = <&vpos>; > + v-neg-supply = <&vneg>; > + > + io-channels = <&adc 0>; > + > + #address-cells = <1>; > + #size-cells = <0>; > + channel@0 { > + reg = <0>; > + adi,toggle-mode; > + adi,output-range-microvolt = <(-10000000) 10000000>; > + }; > + > + channel@1 { > + reg = <1>; > + adi,output-range-microvolt = <0 10000000>; > + }; > + }; > + }; > +... > diff --git a/MAINTAINERS b/MAINTAINERS > index be590c462d91..849800d9cbf7 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -13074,6 +13074,14 @@ S: Maintained > F: Documentation/devicetree/bindings/iio/dac/lltc,ltc1660.yaml > F: drivers/iio/dac/ltc1660.c > > +LTC2664 IIO DAC DRIVER > +M: Michael Hennerich <michael.hennerich@analog.com> > +M: Kim Seer Paller <kimseer.paller@analog.com> > +L: linux-iio@vger.kernel.org > +S: Supported > +W: https://ez.analog.com/linux-software-drivers > +F: Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > + > LTC2688 IIO DAC DRIVER > M: Nuno Sá <nuno.sa@analog.com> > L: linux-iio@vger.kernel.org > -- > 2.34.1 >
> -----Original Message----- > From: Conor Dooley <conor@kernel.org> > Sent: Thursday, June 20, 2024 1:57 AM > To: Paller, Kim Seer <KimSeer.Paller@analog.com> > Cc: linux-kernel@vger.kernel.org; linux-iio@vger.kernel.org; > devicetree@vger.kernel.org; Jonathan Cameron <jic23@kernel.org>; David > Lechner <dlechner@baylibre.com>; Lars-Peter Clausen <lars@metafoo.de>; > Liam Girdwood <lgirdwood@gmail.com>; Mark Brown <broonie@kernel.org>; > Dimitri Fedrau <dima.fedrau@gmail.com>; Krzysztof Kozlowski > <krzk+dt@kernel.org>; Rob Herring <robh@kernel.org>; Conor Dooley > <conor+dt@kernel.org>; Hennerich, Michael > <Michael.Hennerich@analog.com>; Nuno Sá <noname.nuno@gmail.com> > Subject: Re: [PATCH v4 3/5] dt-bindings: iio: dac: Add adi,ltc2664.yaml > > [External] > > On Wed, Jun 19, 2024 at 02:49:02PM +0800, Kim Seer Paller wrote: > > Add documentation for ltc2664. > > > > Co-developed-by: Michael Hennerich <michael.hennerich@analog.com> > > Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> > > Signed-off-by: Kim Seer Paller <kimseer.paller@analog.com> > > --- > > .../bindings/iio/dac/adi,ltc2664.yaml | 167 ++++++++++++++++++ > > MAINTAINERS | 8 + > > 2 files changed, 175 insertions(+) > > create mode 100644 > > Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > > > diff --git > > a/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > b/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > new file mode 100644 > > index 000000000000..be37700e3b1f > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > @@ -0,0 +1,167 @@ > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML 1.2 > > +--- > > +$id: http://devicetree.org/schemas/iio/dac/adi,ltc2664.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: Analog Devices LTC2664 DAC > > + > > +maintainers: > > + - Michael Hennerich <michael.hennerich@analog.com> > > + - Kim Seer Paller <kimseer.paller@analog.com> > > + > > +description: | > > + Analog Devices LTC2664 4 channel, 12-/16-Bit, +-10V DAC > > + > > +https://www.analog.com/media/en/technical-documentation/data-sheets/2 > > +664fa.pdf > > + > > +properties: > > + compatible: > > + enum: > > + - adi,ltc2664 > > + > > + reg: > > + maxItems: 1 > > + > > + spi-max-frequency: > > + maximum: 50000000 > > + > > + vcc-supply: > > + description: Analog Supply Voltage Input. > > + > > + v-pos-supply: > > + description: Positive Supply Voltage Input. > > + > > + v-neg-supply: > > + description: Negative Supply Voltage Input. > > + > > + iovcc-supply: > > + description: Digital Input/Output Supply Voltage. > > + > > + ref-supply: > > + description: > > + Reference Input/Output. The voltage at the REF pin sets the full-scale > > + range of all channels. If not provided the internal reference is used and > > + also provided on the VREF pin. > > + > > + reset-gpios: > > + description: > > + Active-low Asynchronous Clear Input. A logic low at this level-triggered > > + input clears the part to the reset code and range determined by the > > + hardwired option chosen using the MSPAN pins. The control registers are > > + cleared to zero. > > + maxItems: 1 > > + > > + adi,manual-span-operation-config: > > + description: > > + This property must mimic the MSPAN pin configurations. By tying the > MSPAN > > + pins (MSP2, MSP1 and MSP0) to GND and/or VCC, any output range can > be > > + hardware-configured with different mid-scale or zero-scale reset options. > > + The hardware configuration is latched during power on reset for proper > > + operation. > > + 0 - MPS2=GND, MPS1=GND, MSP0=GND (+-10V, reset to 0V) > > + 1 - MPS2=GND, MPS1=GND, MSP0=VCC (+-5V, reset to 0V) > > + 2 - MPS2=GND, MPS1=VCC, MSP0=GND (+-2.5V, reset to 0V) > > + 3 - MPS2=GND, MPS1=VCC, MSP0=VCC (0V to 10, reset to 0V) > > + 4 - MPS2=VCC, MPS1=GND, MSP0=GND (0V to 10V, reset to 5V) > > + 5 - MPS2=VCC, MPS1=GND, MSP0=VCC (0V to 5V, reset to 0V) > > + 6 - MPS2=VCC, MPS1=VCC, MSP0=GND (0V to 5V, reset to 2.5V) > > + 7 - MPS2=VCC, MPS1=VCC, MSP0=VCC (0V to 5V, reset to 0V, enables > SoftSpan) > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + enum: [0, 1, 2, 3, 4, 5, 6, 7] > > Can you explain why this property is required, when below there's one that sets > the ranges in microvolts? Isn't the only new information that this provides the > reset values (in a few cases that it is not 0). > What am I missing? For specifying output range and reset options without relying on software initialization routines, and also for enabling the softspan feature, I think this property seems essential. > > + default: 7 > > + > > + io-channels: > > + description: > > + ADC channel to monitor voltages and temperature at the MUXOUT pin. > > + maxItems: 1 > > + > > + '#address-cells': > > + const: 1 > > + > > + '#size-cells': > > + const: 0 > > + > > +patternProperties: > > + "^channel@[0-3]$": > > + type: object > > + additionalProperties: false > > + > > + properties: > > + reg: > > + description: The channel number representing the DAC output channel. > > + maximum: 3 > > + > > + adi,toggle-mode: > > + description: > > + Set the channel as a toggle enabled channel. Toggle operation enables > > + fast switching of a DAC output between two different DAC codes > without > > + any SPI transaction. > > + type: boolean > > + > > + adi,output-range-microvolt: > > + description: Specify the channel output full scale range. > > + oneOf: > > + - items: > > + - const: 0 > > + - enum: [5000000, 10000000] > > + - items: > > + - const: -5000000 > > + - const: 5000000 > > + - items: > > + - const: -10000000 > > + - const: 10000000 > > + - items: > > + - const: -2500000 > > + - const: 2500000 > > + > > + required: > > + - reg > > + - adi,output-range-microvolt > > + > > +required: > > + - compatible > > + - reg > > + - spi-max-frequency > > + - vcc-supply > > + - iovcc-supply > > + - v-pos-supply > > + - v-neg-supply > > + > > +allOf: > > + - $ref: /schemas/spi/spi-peripheral-props.yaml# > > + > > +additionalProperties: false > > + > > +examples: > > + - | > > + spi { > > + #address-cells = <1>; > > + #size-cells = <0>; > > + dac@0 { > > + compatible = "adi,ltc2664"; > > + reg = <0>; > > + spi-max-frequency = <10000000>; > > + > > + vcc-supply = <&vcc>; > > + iovcc-supply = <&vcc>; > > + ref-supply = <&vref>; > > + v-pos-supply = <&vpos>; > > + v-neg-supply = <&vneg>; > > + > > + io-channels = <&adc 0>; > > + > > + #address-cells = <1>; > > + #size-cells = <0>; > > + channel@0 { > > + reg = <0>; > > + adi,toggle-mode; > > + adi,output-range-microvolt = <(-10000000) 10000000>; > > + }; > > + > > + channel@1 { > > + reg = <1>; > > + adi,output-range-microvolt = <0 10000000>; > > + }; > > + }; > > + }; > > +... > > diff --git a/MAINTAINERS b/MAINTAINERS index > > be590c462d91..849800d9cbf7 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -13074,6 +13074,14 @@ S: Maintained > > F: Documentation/devicetree/bindings/iio/dac/lltc,ltc1660.yaml > > F: drivers/iio/dac/ltc1660.c > > > > +LTC2664 IIO DAC DRIVER > > +M: Michael Hennerich <michael.hennerich@analog.com> > > +M: Kim Seer Paller <kimseer.paller@analog.com> > > +L: linux-iio@vger.kernel.org > > +S: Supported > > +W: https://ez.analog.com/linux-software-drivers > > +F: Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > + > > LTC2688 IIO DAC DRIVER > > M: Nuno Sá <nuno.sa@analog.com> > > L: linux-iio@vger.kernel.org > > -- > > 2.34.1 > >
On Mon, Jun 24, 2024 at 03:13:56PM +0000, Paller, Kim Seer wrote: > > > > -----Original Message----- > > From: Conor Dooley <conor@kernel.org> > > Sent: Thursday, June 20, 2024 1:57 AM > > To: Paller, Kim Seer <KimSeer.Paller@analog.com> > > Cc: linux-kernel@vger.kernel.org; linux-iio@vger.kernel.org; > > devicetree@vger.kernel.org; Jonathan Cameron <jic23@kernel.org>; David > > Lechner <dlechner@baylibre.com>; Lars-Peter Clausen <lars@metafoo.de>; > > Liam Girdwood <lgirdwood@gmail.com>; Mark Brown <broonie@kernel.org>; > > Dimitri Fedrau <dima.fedrau@gmail.com>; Krzysztof Kozlowski > > <krzk+dt@kernel.org>; Rob Herring <robh@kernel.org>; Conor Dooley > > <conor+dt@kernel.org>; Hennerich, Michael > > <Michael.Hennerich@analog.com>; Nuno Sá <noname.nuno@gmail.com> > > Subject: Re: [PATCH v4 3/5] dt-bindings: iio: dac: Add adi,ltc2664.yaml > > > > [External] > > > > On Wed, Jun 19, 2024 at 02:49:02PM +0800, Kim Seer Paller wrote: > > > Add documentation for ltc2664. > > > > > > Co-developed-by: Michael Hennerich <michael.hennerich@analog.com> > > > Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> > > > Signed-off-by: Kim Seer Paller <kimseer.paller@analog.com> > > > --- > > > .../bindings/iio/dac/adi,ltc2664.yaml | 167 ++++++++++++++++++ > > > MAINTAINERS | 8 + > > > 2 files changed, 175 insertions(+) > > > create mode 100644 > > > Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > > > > > diff --git > > > a/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > > b/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > > new file mode 100644 > > > index 000000000000..be37700e3b1f > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml > > > @@ -0,0 +1,167 @@ > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML 1.2 > > > +--- > > > +$id: http://devicetree.org/schemas/iio/dac/adi,ltc2664.yaml# > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > + > > > +title: Analog Devices LTC2664 DAC > > > + > > > +maintainers: > > > + - Michael Hennerich <michael.hennerich@analog.com> > > > + - Kim Seer Paller <kimseer.paller@analog.com> > > > + > > > +description: | > > > + Analog Devices LTC2664 4 channel, 12-/16-Bit, +-10V DAC > > > + > > > +https://www.analog.com/media/en/technical-documentation/data-sheets/2 > > > +664fa.pdf > > > + > > > +properties: > > > + compatible: > > > + enum: > > > + - adi,ltc2664 > > > + > > > + reg: > > > + maxItems: 1 > > > + > > > + spi-max-frequency: > > > + maximum: 50000000 > > > + > > > + vcc-supply: > > > + description: Analog Supply Voltage Input. > > > + > > > + v-pos-supply: > > > + description: Positive Supply Voltage Input. > > > + > > > + v-neg-supply: > > > + description: Negative Supply Voltage Input. > > > + > > > + iovcc-supply: > > > + description: Digital Input/Output Supply Voltage. > > > + > > > + ref-supply: > > > + description: > > > + Reference Input/Output. The voltage at the REF pin sets the full-scale > > > + range of all channels. If not provided the internal reference is used and > > > + also provided on the VREF pin. > > > + > > > + reset-gpios: > > > + description: > > > + Active-low Asynchronous Clear Input. A logic low at this level-triggered > > > + input clears the part to the reset code and range determined by the > > > + hardwired option chosen using the MSPAN pins. The control registers are > > > + cleared to zero. > > > + maxItems: 1 > > > + > > > + adi,manual-span-operation-config: > > > + description: > > > + This property must mimic the MSPAN pin configurations. By tying the > > MSPAN > > > + pins (MSP2, MSP1 and MSP0) to GND and/or VCC, any output range can > > be > > > + hardware-configured with different mid-scale or zero-scale reset options. > > > + The hardware configuration is latched during power on reset for proper > > > + operation. > > > + 0 - MPS2=GND, MPS1=GND, MSP0=GND (+-10V, reset to 0V) > > > + 1 - MPS2=GND, MPS1=GND, MSP0=VCC (+-5V, reset to 0V) > > > + 2 - MPS2=GND, MPS1=VCC, MSP0=GND (+-2.5V, reset to 0V) > > > + 3 - MPS2=GND, MPS1=VCC, MSP0=VCC (0V to 10, reset to 0V) > > > + 4 - MPS2=VCC, MPS1=GND, MSP0=GND (0V to 10V, reset to 5V) > > > + 5 - MPS2=VCC, MPS1=GND, MSP0=VCC (0V to 5V, reset to 0V) > > > + 6 - MPS2=VCC, MPS1=VCC, MSP0=GND (0V to 5V, reset to 2.5V) > > > + 7 - MPS2=VCC, MPS1=VCC, MSP0=VCC (0V to 5V, reset to 0V, enables > > SoftSpan) > > > + $ref: /schemas/types.yaml#/definitions/uint32 > > > + enum: [0, 1, 2, 3, 4, 5, 6, 7] > > > > Can you explain why this property is required, when below there's one that sets > > the ranges in microvolts? Isn't the only new information that this provides the > > reset values (in a few cases that it is not 0). > > What am I missing? > > For specifying output range and reset options without relying on software initialization > routines, and also for enabling the softspan feature, I think this property seems essential. The portion of this information that is duplicated below I do not think should reappear in this property. Really the only additional information is the reset values being at 50% of the range and the SoftSpan
>>> + adi,manual-span-operation-config: >>> + description: >>> + This property must mimic the MSPAN pin configurations. By tying the >> MSPAN >>> + pins (MSP2, MSP1 and MSP0) to GND and/or VCC, any output range can >> be >>> + hardware-configured with different mid-scale or zero-scale reset options. >>> + The hardware configuration is latched during power on reset for proper >>> + operation. >>> + 0 - MPS2=GND, MPS1=GND, MSP0=GND (+-10V, reset to 0V) >>> + 1 - MPS2=GND, MPS1=GND, MSP0=VCC (+-5V, reset to 0V) >>> + 2 - MPS2=GND, MPS1=VCC, MSP0=GND (+-2.5V, reset to 0V) >>> + 3 - MPS2=GND, MPS1=VCC, MSP0=VCC (0V to 10, reset to 0V) >>> + 4 - MPS2=VCC, MPS1=GND, MSP0=GND (0V to 10V, reset to 5V) >>> + 5 - MPS2=VCC, MPS1=GND, MSP0=VCC (0V to 5V, reset to 0V) >>> + 6 - MPS2=VCC, MPS1=VCC, MSP0=GND (0V to 5V, reset to 2.5V) >>> + 7 - MPS2=VCC, MPS1=VCC, MSP0=VCC (0V to 5V, reset to 0V, enables >> SoftSpan) >>> + $ref: /schemas/types.yaml#/definitions/uint32 >>> + enum: [0, 1, 2, 3, 4, 5, 6, 7] >> >> Can you explain why this property is required, when below there's one that sets >> the ranges in microvolts? Isn't the only new information that this provides the >> reset values (in a few cases that it is not 0). >> What am I missing? > > For specifying output range and reset options without relying on software initialization > routines, and also for enabling the softspan feature, I think this property seems essential. So in other words, this describes how the MSP pins are hardwired and the per-channel adi,output-range-microvolt is only permissible if adi,manual-span-operation-config = <7>; (or omitted since 7 is the default) because in that case each individual pin could have a different required range based on what is wire up to it? But if adi,manual-span-operation-config is anything other than 7, then adi,output-range-microvolt should be not allowed since all channels will have the same range because of the hard-wired pins. correct? The description could probably just be simplified to say that this describes how the 3 pins are hardwired and to see Table 4 in the datasheet to understand the actual implications rather than reproducing that table here. But I do agree that we need both properties. I think we are just missing: - if: properties: adi,manual-span-operation-config: const: 7 then: patternProperties: "^channel@[0-3]$": adi,output-range-microvolt: false (not tested - may need two ifs, one with - if: required: - adi,manual-span-operation-config properties: adi,manual-span-operation-config: const: 7 and one with - if: not: required: - adi,manual-span-operation-config to make it work properly) > >>> + default: 7 >>> + >>> + io-channels: >>> + description: >>> + ADC channel to monitor voltages and temperature at the MUXOUT pin. >>> + maxItems: 1 >>> + >>> + '#address-cells': >>> + const: 1 >>> + >>> + '#size-cells': >>> + const: 0 >>> + >>> +patternProperties: >>> + "^channel@[0-3]$": >>> + type: object >>> + additionalProperties: false >>> + >>> + properties: >>> + reg: >>> + description: The channel number representing the DAC output channel. >>> + maximum: 3 >>> + >>> + adi,toggle-mode: >>> + description: >>> + Set the channel as a toggle enabled channel. Toggle operation enables >>> + fast switching of a DAC output between two different DAC codes >> without >>> + any SPI transaction. >>> + type: boolean >>> + >>> + adi,output-range-microvolt: >>> + description: Specify the channel output full scale range. >>> + oneOf: >>> + - items: >>> + - const: 0 >>> + - enum: [5000000, 10000000] >>> + - items: >>> + - const: -5000000 >>> + - const: 5000000 >>> + - items: >>> + - const: -10000000 >>> + - const: 10000000 >>> + - items: >>> + - const: -2500000 >>> + - const: 2500000 >>> + >>> + required: >>> + - reg >>> + - adi,output-range-microvolt And adi,output-range-microvolt should not be required. When SoftSpan is not available (because MSP != 0x7), then the range is determined by adi,manual-span-operation-config. And even when adi,manual-span-operation-config = <7>, there is still a default range, so adi,output-range-microvolt should still not be required in that case.
> -----Original Message----- > From: David Lechner <dlechner@baylibre.com> > Sent: Tuesday, June 25, 2024 12:49 AM > To: Paller, Kim Seer <KimSeer.Paller@analog.com>; Conor Dooley > <conor@kernel.org> > Cc: linux-kernel@vger.kernel.org; linux-iio@vger.kernel.org; > devicetree@vger.kernel.org; Jonathan Cameron <jic23@kernel.org>; Lars-Peter > Clausen <lars@metafoo.de>; Liam Girdwood <lgirdwood@gmail.com>; Mark > Brown <broonie@kernel.org>; Dimitri Fedrau <dima.fedrau@gmail.com>; > Krzysztof Kozlowski <krzk+dt@kernel.org>; Rob Herring <robh@kernel.org>; > Conor Dooley <conor+dt@kernel.org>; Hennerich, Michael > <Michael.Hennerich@analog.com>; Nuno Sá <noname.nuno@gmail.com> > Subject: Re: [PATCH v4 3/5] dt-bindings: iio: dac: Add adi,ltc2664.yaml > > [External] > > > >>> + adi,manual-span-operation-config: > >>> + description: > >>> + This property must mimic the MSPAN pin configurations. By tying the > >> MSPAN > >>> + pins (MSP2, MSP1 and MSP0) to GND and/or VCC, any output range > can > >> be > >>> + hardware-configured with different mid-scale or zero-scale reset > options. > >>> + The hardware configuration is latched during power on reset for > proper > >>> + operation. > >>> + 0 - MPS2=GND, MPS1=GND, MSP0=GND (+-10V, reset to 0V) > >>> + 1 - MPS2=GND, MPS1=GND, MSP0=VCC (+-5V, reset to 0V) > >>> + 2 - MPS2=GND, MPS1=VCC, MSP0=GND (+-2.5V, reset to 0V) > >>> + 3 - MPS2=GND, MPS1=VCC, MSP0=VCC (0V to 10, reset to 0V) > >>> + 4 - MPS2=VCC, MPS1=GND, MSP0=GND (0V to 10V, reset to 5V) > >>> + 5 - MPS2=VCC, MPS1=GND, MSP0=VCC (0V to 5V, reset to 0V) > >>> + 6 - MPS2=VCC, MPS1=VCC, MSP0=GND (0V to 5V, reset to 2.5V) > >>> + 7 - MPS2=VCC, MPS1=VCC, MSP0=VCC (0V to 5V, reset to 0V, enables > >> SoftSpan) > >>> + $ref: /schemas/types.yaml#/definitions/uint32 > >>> + enum: [0, 1, 2, 3, 4, 5, 6, 7] > >> > >> Can you explain why this property is required, when below there's one that > sets > >> the ranges in microvolts? Isn't the only new information that this provides > the > >> reset values (in a few cases that it is not 0). > >> What am I missing? > > > > For specifying output range and reset options without relying on software > initialization > > routines, and also for enabling the softspan feature, I think this property > seems essential. > > So in other words, this describes how the MSP pins are hardwired and > the per-channel adi,output-range-microvolt is only permissible if > > adi,manual-span-operation-config = <7>; > > (or omitted since 7 is the default) > > because in that case each individual pin could have a different > required range based on what is wire up to it? > > But if adi,manual-span-operation-config is anything other than 7, > then adi,output-range-microvolt should be not allowed since all > channels will have the same range because of the hard-wired pins. > > correct? That's correct. > The description could probably just be simplified to say that > this describes how the 3 pins are hardwired and to see Table 4 > in the datasheet to understand the actual implications rather > than reproducing that table here. > > But I do agree that we need both properties. I think we are > just missing: > > - if: > properties: > adi,manual-span-operation-config: > const: 7 > then: > patternProperties: > "^channel@[0-3]$": > adi,output-range-microvolt: false > > (not tested - may need two ifs, one with > > - if: > required: > - adi,manual-span-operation-config > properties: > adi,manual-span-operation-config: > const: 7 > > and one with > > - if: > not: > required: > - adi,manual-span-operation-config > > to make it work properly) > > > > >>> + default: 7 > >>> + > >>> + io-channels: > >>> + description: > >>> + ADC channel to monitor voltages and temperature at the MUXOUT > pin. > >>> + maxItems: 1 > >>> + > >>> + '#address-cells': > >>> + const: 1 > >>> + > >>> + '#size-cells': > >>> + const: 0 > >>> + > >>> +patternProperties: > >>> + "^channel@[0-3]$": > >>> + type: object > >>> + additionalProperties: false > >>> + > >>> + properties: > >>> + reg: > >>> + description: The channel number representing the DAC output > channel. > >>> + maximum: 3 > >>> + > >>> + adi,toggle-mode: > >>> + description: > >>> + Set the channel as a toggle enabled channel. Toggle operation > enables > >>> + fast switching of a DAC output between two different DAC codes > >> without > >>> + any SPI transaction. > >>> + type: boolean > >>> + > >>> + adi,output-range-microvolt: > >>> + description: Specify the channel output full scale range. > >>> + oneOf: > >>> + - items: > >>> + - const: 0 > >>> + - enum: [5000000, 10000000] > >>> + - items: > >>> + - const: -5000000 > >>> + - const: 5000000 > >>> + - items: > >>> + - const: -10000000 > >>> + - const: 10000000 > >>> + - items: > >>> + - const: -2500000 > >>> + - const: 2500000 > >>> + > >>> + required: > >>> + - reg > >>> + - adi,output-range-microvolt > > And adi,output-range-microvolt should not be required. When SoftSpan > is not available (because MSP != 0x7), then the range is determined > by adi,manual-span-operation-config. > > And even when adi,manual-span-operation-config = <7>, there is still > a default range, so adi,output-range-microvolt should still not be > required in that case. This makes sense how this operates. Appreciate the detailed feedback.
diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml new file mode 100644 index 000000000000..be37700e3b1f --- /dev/null +++ b/Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml @@ -0,0 +1,167 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/dac/adi,ltc2664.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Analog Devices LTC2664 DAC + +maintainers: + - Michael Hennerich <michael.hennerich@analog.com> + - Kim Seer Paller <kimseer.paller@analog.com> + +description: | + Analog Devices LTC2664 4 channel, 12-/16-Bit, +-10V DAC + https://www.analog.com/media/en/technical-documentation/data-sheets/2664fa.pdf + +properties: + compatible: + enum: + - adi,ltc2664 + + reg: + maxItems: 1 + + spi-max-frequency: + maximum: 50000000 + + vcc-supply: + description: Analog Supply Voltage Input. + + v-pos-supply: + description: Positive Supply Voltage Input. + + v-neg-supply: + description: Negative Supply Voltage Input. + + iovcc-supply: + description: Digital Input/Output Supply Voltage. + + ref-supply: + description: + Reference Input/Output. The voltage at the REF pin sets the full-scale + range of all channels. If not provided the internal reference is used and + also provided on the VREF pin. + + reset-gpios: + description: + Active-low Asynchronous Clear Input. A logic low at this level-triggered + input clears the part to the reset code and range determined by the + hardwired option chosen using the MSPAN pins. The control registers are + cleared to zero. + maxItems: 1 + + adi,manual-span-operation-config: + description: + This property must mimic the MSPAN pin configurations. By tying the MSPAN + pins (MSP2, MSP1 and MSP0) to GND and/or VCC, any output range can be + hardware-configured with different mid-scale or zero-scale reset options. + The hardware configuration is latched during power on reset for proper + operation. + 0 - MPS2=GND, MPS1=GND, MSP0=GND (+-10V, reset to 0V) + 1 - MPS2=GND, MPS1=GND, MSP0=VCC (+-5V, reset to 0V) + 2 - MPS2=GND, MPS1=VCC, MSP0=GND (+-2.5V, reset to 0V) + 3 - MPS2=GND, MPS1=VCC, MSP0=VCC (0V to 10, reset to 0V) + 4 - MPS2=VCC, MPS1=GND, MSP0=GND (0V to 10V, reset to 5V) + 5 - MPS2=VCC, MPS1=GND, MSP0=VCC (0V to 5V, reset to 0V) + 6 - MPS2=VCC, MPS1=VCC, MSP0=GND (0V to 5V, reset to 2.5V) + 7 - MPS2=VCC, MPS1=VCC, MSP0=VCC (0V to 5V, reset to 0V, enables SoftSpan) + $ref: /schemas/types.yaml#/definitions/uint32 + enum: [0, 1, 2, 3, 4, 5, 6, 7] + default: 7 + + io-channels: + description: + ADC channel to monitor voltages and temperature at the MUXOUT pin. + maxItems: 1 + + '#address-cells': + const: 1 + + '#size-cells': + const: 0 + +patternProperties: + "^channel@[0-3]$": + type: object + additionalProperties: false + + properties: + reg: + description: The channel number representing the DAC output channel. + maximum: 3 + + adi,toggle-mode: + description: + Set the channel as a toggle enabled channel. Toggle operation enables + fast switching of a DAC output between two different DAC codes without + any SPI transaction. + type: boolean + + adi,output-range-microvolt: + description: Specify the channel output full scale range. + oneOf: + - items: + - const: 0 + - enum: [5000000, 10000000] + - items: + - const: -5000000 + - const: 5000000 + - items: + - const: -10000000 + - const: 10000000 + - items: + - const: -2500000 + - const: 2500000 + + required: + - reg + - adi,output-range-microvolt + +required: + - compatible + - reg + - spi-max-frequency + - vcc-supply + - iovcc-supply + - v-pos-supply + - v-neg-supply + +allOf: + - $ref: /schemas/spi/spi-peripheral-props.yaml# + +additionalProperties: false + +examples: + - | + spi { + #address-cells = <1>; + #size-cells = <0>; + dac@0 { + compatible = "adi,ltc2664"; + reg = <0>; + spi-max-frequency = <10000000>; + + vcc-supply = <&vcc>; + iovcc-supply = <&vcc>; + ref-supply = <&vref>; + v-pos-supply = <&vpos>; + v-neg-supply = <&vneg>; + + io-channels = <&adc 0>; + + #address-cells = <1>; + #size-cells = <0>; + channel@0 { + reg = <0>; + adi,toggle-mode; + adi,output-range-microvolt = <(-10000000) 10000000>; + }; + + channel@1 { + reg = <1>; + adi,output-range-microvolt = <0 10000000>; + }; + }; + }; +... diff --git a/MAINTAINERS b/MAINTAINERS index be590c462d91..849800d9cbf7 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13074,6 +13074,14 @@ S: Maintained F: Documentation/devicetree/bindings/iio/dac/lltc,ltc1660.yaml F: drivers/iio/dac/ltc1660.c +LTC2664 IIO DAC DRIVER +M: Michael Hennerich <michael.hennerich@analog.com> +M: Kim Seer Paller <kimseer.paller@analog.com> +L: linux-iio@vger.kernel.org +S: Supported +W: https://ez.analog.com/linux-software-drivers +F: Documentation/devicetree/bindings/iio/dac/adi,ltc2664.yaml + LTC2688 IIO DAC DRIVER M: Nuno Sá <nuno.sa@analog.com> L: linux-iio@vger.kernel.org