[RFC v2 03/11] dt-bindings: iio: stm32-dfsdm-adc: add scaling support
Olivier MOYSAN
olivier.moysan at foss.st.com
Thu Aug 31 08:53:00 PDT 2023
Hi Rob,
On 8/11/23 19:10, Rob Herring wrote:
> On Thu, Jul 27, 2023 at 05:03:14PM +0200, Olivier Moysan wrote:
>> Add scaling support to STM32 DFSDM.
>>
>> This introduces the following changes:
>
> Why?
>
This RFC is an attempt to support scaling through a change in DFSDM
topology.
These changes have some impacts on DFSDM and sd modulator bindings.
To keep things simple in this RFC, I skipped legacy support, to put the
emphasis on the new bindings proposal.
There are two changes here: adoption of the generic IIO bindings and new
"io-backends" property. This needs to be put in two separate patches at
the end, I think (as already done for driver patches)
Anyway, the current bindings would become deprecated with these changes.
I still have to consider how to support these legacy bindings for next
step, However.
BRs
Olivier
>> - Add ADC generic channel binding and remove support of deprecated
>> channel bindings.
>
> When was it deprecated?
>
>> - DFSDM is now implemented as a channel provider, so remove io-channels
>> properties.
>> - Add iio-backend property to connect DFSDM to an SD modulator.
>
> io-backends
>
> All sorts of ABI issues with this change. Please explain why you don't
> care.
>
>>
>> Signed-off-by: Olivier Moysan <olivier.moysan at foss.st.com>
>> ---
>> .../bindings/iio/adc/st,stm32-dfsdm-adc.yaml | 189 ++++++------------
>> 1 file changed, 63 insertions(+), 126 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 1970503389aa..128545cedc7f 100644
>> --- a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml
>> +++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml
>> @@ -85,22 +85,14 @@ patternProperties:
>> description: Specifies the DFSDM filter instance used.
>> maxItems: 1
>>
>> - interrupts:
>> - maxItems: 1
>> + '#address-cells':
>> + const: 1
>>
>> - st,adc-channels:
>> - description: |
>> - List of single-ended channels muxed for this ADC.
>> - On stm32h7 and stm32mp1:
>> - - For st,stm32-dfsdm-adc: up to 8 channels numbered from 0 to 7.
>> - - For st,stm32-dfsdm-dmic: 1 channel numbered from 0 to 7.
>> - $ref: /schemas/types.yaml#/definitions/uint32-array
>> - items:
>> - minimum: 0
>> - maximum: 7
>> + '#size-cells':
>> + const: 0
>>
>> - st,adc-channel-names:
>> - description: List of single-ended channel names.
>> + interrupts:
>> + maxItems: 1
>>
>> st,filter-order:
>> description: |
>> @@ -111,39 +103,6 @@ patternProperties:
>> $ref: /schemas/types.yaml#/definitions/uint32
>> maximum: 5
>>
>> - "#io-channel-cells":
>> - const: 1
>> -
>> - st,adc-channel-types:
>> - 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
>> - items:
>> - enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
>> - $ref: /schemas/types.yaml#/definitions/non-unique-string-array
>> -
>> - 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).
>> - items:
>> - enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
>> - $ref: /schemas/types.yaml#/definitions/non-unique-string-array
>> -
>> - st,adc-alt-channel:
>> - description:
>> - Must be defined if two sigma delta modulators are
>> - connected on same SPI input.
>> - If not set, channel n is connected to SPI input n.
>> - If set, channel n is connected to SPI input n + 1.
>> - type: boolean
>> -
>> st,filter0-sync:
>> description:
>> Set to 1 to synchronize with DFSDM filter instance 0.
>> @@ -157,14 +116,68 @@ patternProperties:
>> items:
>> - const: rx
>>
>> + patternProperties:
>> + "^channel@([0-9]|1[0-9])$":
>> + type: object
>> + $ref: "adc.yaml"
>> + description: Represents the external channels which are connected to the DFSDM.
>> +
>> + properties:
>> + reg:
>> + items:
>> + minimum: 0
>> + maximum: 19
>> +
>> + label:
>> + description: |
>> + Unique name to identify channel.
>> +
>> + st,adc-channel-types:
>> + 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
>> + items:
>> + enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
>> + $ref: /schemas/types.yaml#/definitions/non-unique-string-array
>> +
>> + 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).
>> + items:
>> + enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
>> + $ref: /schemas/types.yaml#/definitions/non-unique-string-array
>> +
>> + 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: |
>> + phandle to an external sigma delta modulator or internal ADC output.
>> + $ref: /schemas/types.yaml#/definitions/phandle
>> +
>> + required:
>> + - reg
>> + - io-backends
>> +
>> + additionalProperties: false
>> +
>> required:
>> - compatible
>> - reg
>> - interrupts
>> - - st,adc-channels
>> - - st,adc-channel-names
>> - st,filter-order
>> - - "#io-channel-cells"
>>
>> allOf:
>> - if:
>> @@ -175,14 +188,6 @@ patternProperties:
>>
>> then:
>> properties:
>> - st,adc-channels:
>> - minItems: 1
>> - maxItems: 8
>> -
>> - st,adc-channel-names:
>> - minItems: 1
>> - maxItems: 8
>> -
>> st,adc-channel-types:
>> minItems: 1
>> maxItems: 8
>> @@ -191,14 +196,6 @@ patternProperties:
>> minItems: 1
>> maxItems: 8
>>
>> - io-channels:
>> - description:
>> - From common IIO binding. Used to pipe external sigma delta
>> - modulator or internal ADC output to DFSDM channel.
>> -
>> - required:
>> - - io-channels
>> -
>> - if:
>> properties:
>> compatible:
>> @@ -207,12 +204,6 @@ patternProperties:
>>
>> then:
>> properties:
>> - st,adc-channels:
>> - maxItems: 1
>> -
>> - st,adc-channel-names:
>> - maxItems: 1
>> -
>> st,adc-channel-types:
>> maxItems: 1
>>
>> @@ -237,15 +228,9 @@ patternProperties:
>> "#sound-dai-cells":
>> const: 0
>>
>> - io-channels:
>> - description:
>> - From common IIO binding. Used to pipe external sigma delta
>> - modulator or internal ADC output to DFSDM channel.
>> -
>> required:
>> - compatible
>> - "#sound-dai-cells"
>> - - io-channels
>>
>> allOf:
>> - if:
>> @@ -278,52 +263,4 @@ allOf:
>> minimum: 0
>> maximum: 5
>>
>> -examples:
>> - - |
>> - #include <dt-bindings/interrupt-controller/arm-gic.h>
>> - #include <dt-bindings/clock/stm32mp1-clks.h>
>> - dfsdm: dfsdm at 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>;
>> -
>> - dfsdm0: filter at 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>;
>> - st,adc-channels = <1>;
>> - st,adc-channel-names = "dmic0";
>> - st,adc-channel-types = "SPI_R";
>> - st,adc-channel-clk-src = "CLKOUT";
>> - st,filter-order = <5>;
>> -
>> - asoc_pdm0: dfsdm-dai {
>> - compatible = "st,stm32h7-dfsdm-dai";
>> - #sound-dai-cells = <0>;
>> - io-channels = <&dfsdm0 0>;
>> - };
>> - };
>> -
>> - dfsdm_pdm1: filter at 1 {
>> - compatible = "st,stm32-dfsdm-adc";
>> - reg = <1>;
>> - interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
>> - dmas = <&dmamux1 102 0x400 0x01>;
>> - dma-names = "rx";
>> - #io-channel-cells = <1>;
>> - st,adc-channels = <2 3>;
>> - st,adc-channel-names = "in2", "in3";
>> - st,adc-channel-types = "SPI_R", "SPI_R";
>> - st,adc-channel-clk-src = "CLKOUT_F", "CLKOUT_F";
>> - io-channels = <&sd_adc2 &sd_adc3>;
>> - st,filter-order = <1>;
>> - };
>> - };
>> -
>> ...
>> --
>> 2.25.1
>>
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