Re: [PATCH v4 4/8] dt-bindings: iio: dfsdm: move to backend framework

Rob Herring
2024-07-08T17:09:02Z

On Thu, Jul 04, 2024 at 05:53:32PM +0200, Olivier Moysan wrote:
> Change the DFSDM binding to use the new IIO backend framework,
> along with the adoption of IIO generic channels.
> This binding change allows to add scaling support to the DFSDM.
>
> Keep the legacy binding as deprecated for backward compatibility.
>
> The io-backends property is supported only in generic IIO channel
> binding.
>
> - Channel description with the generic binding (Audio and Analog):
>
> Properties superseded by generic properties:
> st,adc-channels: becomes "reg" property in channel node
> st,adc-channel-names: becomes "label" property in channel node
> Properties moved to channel child node:
> st,adc-channel-types: becomes st,adc-channel-type
> st,adc-channel-clk-src, st,adc-alt-channel
>
> - Analog binding:
>
> DFSDM filter channel is configured as an IIO backend consumer.
> Add io-backends property in channel child nodes.
>
> DFSDM is no more configured as a channel consumer from SD modulator.
> Use of io-channels in DFSDM node is deprecated.
>
> - Audio binding:
>
> DFSDM audio DAI is configured as a channel consumer from DFSDM filter.
> No change compare to legacy.
>
> Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
> ---
> .../bindings/iio/adc/st,stm32-dfsdm-adc.yaml | 153 +++++++++++++++++-
> 1 file changed, 147 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml
> index 2722edab1d9a..5a5bc8b96402 100644
> --- a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml
> +++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml
> @@ -102,9 +102,11 @@ patternProperties:
> items:
> minimum: 0
> maximum: 7
> + deprecated: true
>
> st,adc-channel-names:
> description: List of single-ended channel names.
> + deprecated: true
>
> st,filter-order:
> description: |
> @@ -118,6 +120,12 @@ patternProperties:
> "#io-channel-cells":
> const: 1
>
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> st,adc-channel-types:
> description: |
> Single-ended channel input type.
> @@ -128,6 +136,7 @@ patternProperties:
> items:
> enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
> $ref: /schemas/types.yaml#/definitions/non-unique-string-array
> + deprecated: true
>
> st,adc-channel-clk-src:
> description: |
> @@ -139,6 +148,7 @@ patternProperties:
> items:
> enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
> $ref: /schemas/types.yaml#/definitions/non-unique-string-array
> + deprecated: true
>
> st,adc-alt-channel:
> description:
> @@ -147,6 +157,7 @@ patternProperties:
> If not set, channel n is connected to SPI input n.
> If set, channel n is connected to SPI input n + 1.
> type: boolean
> + deprecated: true
>
> st,filter0-sync:
> description:
> @@ -165,11 +176,60 @@ patternProperties:
> - compatible
> - reg
> - interrupts
> - - st,adc-channels
> - - st,adc-channel-names
> - st,filter-order
> - "#io-channel-cells"
>
> + patternProperties:
> + "^channel@([0-7])$":
> + type: object
> + $ref: adc.yaml
> + unevaluatedProperties: false
> + description: Represents the external channels which are connected to the DFSDM.
> +
> + properties:
> + reg:
> + maxItems: 1

Instead:

maximum: 7

> +
> + label:
> + description:
> + Unique name to identify which channel this is.
> +
> + st,adc-channel-type:
> + description: |
> + Single-ended channel input type.
> + - "SPI_R": SPI with data on rising edge (default)
> + - "SPI_F": SPI with data on falling edge
> + - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
> + - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
> + $ref: /schemas/types.yaml#/definitions/string
> + enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
> +
> + st,adc-channel-clk-src:
> + description: |
> + Conversion clock source.
> + - "CLKIN": external SPI clock (CLKIN x)
> + - "CLKOUT": internal SPI clock (CLKOUT) (default)
> + - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
> + - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
> + $ref: /schemas/types.yaml#/definitions/string
> + enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
> +
> + st,adc-alt-channel:
> + description:
> + Must be defined if two sigma delta modulators are
> + connected on same SPI input.
> + If not set, channel n is connected to SPI input n.
> + If set, channel n is connected to SPI input n + 1.
> + type: boolean
> +
> + io-backends:
> + description:
> + Used to pipe external sigma delta modulator or internal ADC backend to DFSDM channel.
> + maxItems: 1
> +
> + required:
> + - reg
> +
> allOf:
> - if:
> properties:
> @@ -199,9 +259,19 @@ patternProperties:
> description:
> From common IIO binding. Used to pipe external sigma delta
> modulator or internal ADC output to DFSDM channel.
> + deprecated: true
>
> - required:
> - - io-channels
> + if:
> + required:
> + - st,adc-channels
> + then:
> + required:
> + - io-channels
> +
> + patternProperties:
> + "^channel@([0-9])$":

Is it 8 or 10 channels?

> + required:
> + - io-backends
>
> - if:
> properties:
> @@ -298,7 +368,77 @@ examples:
> #address-cells = <1>;
> #size-cells = <0>;
>
> + // Example 1: Audio use case with generic binding
> dfsdm0: filter@0 {
> + compatible = "st,stm32-dfsdm-dmic";
> + reg = <0>;
> + interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
> + dmas = <&dmamux1 101 0x400 0x01>;
> + dma-names = "rx";
> + #io-channel-cells = <1>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + st,filter-order = <5>;
> +
> + channel@1 {
> + reg = <1>;
> + label = "dmic0";
> + st,adc-channel-type = "SPI_R";
> + st,adc-channel-clk-src = "CLKOUT";
> + st,adc-alt-channel;
> + };
> +
> + asoc_pdm0: dfsdm-dai {
> + compatible = "st,stm32h7-dfsdm-dai";
> + #sound-dai-cells = <0>;
> + io-channels = <&dfsdm0 0>;
> + };
> + };
> +
> + // Example 1: Analog use case with generic binding

2nd example 1?

> + dfsdm1: filter@1 {
> + compatible = "st,stm32-dfsdm-adc";
> + reg = <1>;
> + interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
> + dmas = <&dmamux1 102 0x400 0x01>;
> + dma-names = "rx";
> + st,filter-order = <1>;
> + #io-channel-cells = <1>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + channel@2 {
> + reg = <2>;
> + label = "in2";
> + st,adc-channel-type = "SPI_F";
> + st,adc-channel-clk-src = "CLKOUT";
> + st,adc-alt-channel;
> + io-backends = <&sd_adc2>;
> + };
> +
> + channel@3 {
> + reg = <3>;
> + label = "in3";
> + st,adc-channel-type = "SPI_R";
> + st,adc-channel-clk-src = "CLKOUT";
> + io-backends = <&sd_adc3>;
> + };
> + };
> + };
> +
> + - |
> + #include <dt-bindings/interrupt-controller/arm-gic.h>
> + #include <dt-bindings/clock/stm32mp1-clks.h>
> + dfsdm_2: dfsdm@4400d000 {
> + compatible = "st,stm32mp1-dfsdm";
> + reg = <0x4400d000 0x800>;
> + clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>;
> + clock-names = "dfsdm", "audio";
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + // Example 3: Audio use case with legacy binding

I don't think it is worthwhile to show how to use the deprecated
binding.

> + dfsdm0_2: filter@0 {
> compatible = "st,stm32-dfsdm-dmic";
> reg = <0>;
> interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
> @@ -311,14 +451,15 @@ examples:
> st,adc-channel-clk-src = "CLKOUT";
> st,filter-order = <5>;
>
> - asoc_pdm0: dfsdm-dai {
> + asoc_pdm0_2: dfsdm-dai {
> compatible = "st,stm32h7-dfsdm-dai";
> #sound-dai-cells = <0>;
> io-channels = <&dfsdm0 0>;
> };
> };
>
> - dfsdm_pdm1: filter@1 {
> + // Example 3: Analog use case with legacy binding
> + dfsdm1_2: filter@1 {
> compatible = "st,stm32-dfsdm-adc";
> reg = <1>;
> interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
> --
> 2.25.1
>