Re: [PATCH 01/10] dt-bindings: mfd: Add documentation for ad242x

Rob Herring
2019-12-19T19:29:51Z

On Mon, Dec 09, 2019 at 07:35:01PM +0100, Daniel Mack wrote:
> This patch adds documentation on the top-level MFD support for AD242x
> devices. The bindings implemented by drivers for sub-devices of the
> MFD are documented in other files in their respective subsystems.
>
> The example in this file is referred to by other documents.
>
> Signed-off-by: Daniel Mack <daniel@zonque.org>
> ---
> .../bindings/mfd/adi,ad242x-bus.yaml | 29 +++
> .../bindings/mfd/adi,ad242x-master.yaml | 235 ++++++++++++++++++
> .../bindings/mfd/adi,ad242x-slave.yaml | 108 ++++++++
> 3 files changed, 372 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mfd/adi,ad242x-bus.yaml
> create mode 100644 Documentation/devicetree/bindings/mfd/adi,ad242x-master.yaml
> create mode 100644 Documentation/devicetree/bindings/mfd/adi,ad242x-slave.yaml
>
> diff --git a/Documentation/devicetree/bindings/mfd/adi,ad242x-bus.yaml b/Documentation/devicetree/bindings/mfd/adi,ad242x-bus.yaml
> new file mode 100644
> index 000000000000..89ca8d009bb9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/adi,ad242x-bus.yaml
> @@ -0,0 +1,29 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/mfd/adi,ad242x-bus.yaml#"
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> +
> +title: Analog Devices AD242x A²B bus node
> +
> +maintainers:
> + - Daniel Mack <daniel@zonque.org>
> +
> +description: |
> + AD242x slave nodes represent the secondary I²C address a master node
> + transceiver exposes on the bus.
> +
> +properties:
> + compatible:
> + enum:
> + - adi,ad2428w-bus

Where is this in the example?

Is A2B a standard thing? If so, then shouldn't some of this be split
into a A2B binding and then AD242x specific binding?

> +
> + reg:
> + maxItems: 1
> + description: |
> + The secondary I²C address of the master node
> + (called 'BUS' in the datasheet)
> +
> +required:
> + - compatible
> + - reg
> diff --git a/Documentation/devicetree/bindings/mfd/adi,ad242x-master.yaml b/Documentation/devicetree/bindings/mfd/adi,ad242x-master.yaml
> new file mode 100644
> index 000000000000..649510575a79
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/adi,ad242x-master.yaml
> @@ -0,0 +1,235 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/mfd/adi,ad242x-master.yaml#"
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> +
> +title: Analog Devices AD242x A²B master node transceiver
> +
> +maintainers:
> + - Daniel Mack <daniel@zonque.org>
> +
> +description: |
> + AD242x devices are A²B (Automotive Audio Bus) transceivers that are connected
> + to each other in a daisy-chain. The payload transported on that bus includes
> + multi-channel audio, I²C, GPIOs and others.
> +
> + The datasheet is located here:
> +
> + https://www.analog.com/media/en/technical-documentation/user-guides/AD242x_TRM_Rev1.1.pdf
> +
> + The primary node in the chain is called the master node, and the nodes in the
> + chain are called slave nodes. A master can address up to 15 slave nodes. The
> + master node exposes two I²C addresses, one for accessing the registers on the
> + node itself, and one for registers on one of the slave nodes.
> +
> +properties:
> + compatible:
> + enum:
> + - adi,ad2428w-master
> +
> + reg:
> + maxItems: 1
> + description: |
> + The primary I²C address of the master node
> + (called 'BASE' in the datasheet)
> +
> + clocks:
> + minItems: 1
> +
> + clock-names:
> + $ref: /schemas/types.yaml#/definitions/string-array
> + const: sync
> +
> + clock-frequency:
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + enum: [44100, 48000]
> + description: |
> + Specifies the clock frequency in Hz to configure on the given sync clock.
> + If not specified, the clock is expected to already be configured to either
> + 44100 or 48000 Hz.
> +
> + interrupts:
> + maxItems: 1
> +
> + adi,a2b-bus:
> + $ref: '/schemas/types.yaml#/definitions/phandle'
> + description: Specifies the bus handle node
> +
> + adi,upstream-slot-size:
> + description: The size for upstream slots
> + allOf:
> + - $ref: '/schemas/types.yaml#/definitions/uint32'
> + - enum: [8, 12, 16, 20, 24, 28, 32]
> +
> + adi,downstream-slot-size:
> + description: The size for downstream slots
> + allOf:
> + - $ref: '/schemas/types.yaml#/definitions/uint32'
> + - enum: [8, 12, 16, 20, 24, 28, 32]
> +
> + adi,tdm-mode:
> + description: The TDM mode to use
> + allOf:
> + - $ref: '/schemas/types.yaml#/definitions/uint32'
> + - enum: [2, 4, 8, 12, 16, 20, 24, 32]
> +
> + adi,tdm-slot-size:
> + description: The TDM slot size to use
> + allOf:
> + - $ref: '/schemas/types.yaml#/definitions/uint32'
> + - enum: [16, 32]
> +
> + adi,alternate-upstream-slot-format:
> + description: Selects the alternate format for upstream slots
> + type: boolean
> +
> + adi,alternate-downstream-slot-format:
> + description: Selects the alternate format for downstream slots
> + type: boolean
> +
> + adi,invert-xcvr-b:
> + description: Inverts the LVDS XCVR B data line
> + type: boolean
> +
> + adi,alternating-sync:
> + description: Drives the SYNC pin for I²S operation
> + type: boolean
> +
> + adi,invert-sync:
> + description: Invert the SYNC pin
> + type: boolean
> +
> + adi,early-sync:
> + description: |
> + Make the SYNC pin change one cycle before the first slot is transmitted
> + type: boolean
> +
> + adi,spread-a2b-clock:
> + description: Enables spread spectrum mode for A²B bus clocks
> + type: boolean
> +
> + adi,spread-a2b-i2s-clock:
> + description: Enables spread spectrum mode for both A²B and I²S clocks
> + type: boolean
> +
> + adi,spread-spectrum-high:
> + description: Selects high spectrum spreading mode
> + type: boolean
> +
> +required:
> + - compatible
> + - reg
> + - clocks
> + - clock-names
> + - adi,a2b-bus
> + - adi,upstream-slot-size
> + - adi,downstream-slot-size
> + - adi,tdm-mode
> + - adi,tdm-slot-size
> +
> +examples:
> + - |
> + sync_clock: clock {
> + compatible = "fixed-clock";
> + #clock-cells = <0>;
> + clock-frequency = <48000>;
> + };
> +
> + i2c-bus {
> + ad2428w-master@68 {
> + reg = <0x68>;
> + compatible = "adi,ad2428w-master";
> + adi,a2b-bus = <&a2b_bus>;
> + clocks = <&sync_clock>;
> + clock-names = "sync";
> +
> + adi,upstream-slot-size = <24>;
> + adi,downstream-slot-size = <24>;
> + adi,tdm-mode = <2>;
> + adi,tdm-slot-size = <32>;
> + adi,alternating-sync;
> + adi,early-sync;
> +
> + codec {
> + compatible = "adi,ad2428w-codec";
> + #sound-dai-cells = <1>;
> + };
> +
> + clock {
> + compatible = "adi,ad2428w-clk";
> + #clock-cells = <1>;
> + clock-output-names = "master-clk1", "master-clk2";
> + };
> +
> + nodes {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + node@0 {
> + compatible = "adi,ad2428w-slave";
> + reg = <0>;
> +
> + adi,alternating-sync;
> + adi,early-sync;
> + adi,invert-sync;
> + adi,tdm-mode = <8>;
> + adi,tdm-slot-size = <32>;
> +
> + downstream {
> + rx-slots = <2 3 6 7 8 9>;
> + #tx-slots = <4>;
> + #forward-slots = <6>;
> + };
> +
> + upstream {
> + rx-slots = <0 1 6 7 8 9>;
> + #tx-slots = <4>;
> + #forward-slots = <6>;
> + };
> +
> + a2bgpio: gpio {
> + compatible = "adi,ad2428w-gpio";
> + gpio-controller;
> + #gpio-cells = <2>;
> +
> + gpio-over-distance {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + pin@0 {
> + reg = <0>;
> + adi,virtual-port-mask = <0x01>;
> + };
> + };
> + };
> +
> + i2c {
> + compatible = "adi,ad2428w-i2c";
> + clock-frequency = <400000>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + // I²C client devices located on the remote side
> + eeprom-top@52 {
> + reg = <0x52>;
> + compatible = "atmel,24c02";
> + read-only;
> + };
> + };
> +
> + a2bclk: clock {
> + compatible = "adi,ad2428w-clk";
> + #clock-cells = <1>;
> + clock-output-names = "node0-clk1", "node0-clk2";
> + };
> +
> + codec {
> + compatible = "adi,ad2428w-codec";
> + #sound-dai-cells = <1>;
> + adi,pdm-highpass-filter;
> + };
> + };
> + };
> + };
> + };
> diff --git a/Documentation/devicetree/bindings/mfd/adi,ad242x-slave.yaml b/Documentation/devicetree/bindings/mfd/adi,ad242x-slave.yaml
> new file mode 100644
> index 000000000000..3bea04dff267
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/adi,ad242x-slave.yaml
> @@ -0,0 +1,108 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/mfd/adi,ad242x-slave.yaml#"
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> +
> +title: Analog Devices AD242x A²B slave node transceiver
> +
> +maintainers:
> + - Daniel Mack <daniel@zonque.org>
> +
> +description: |
> + AD242x slave nodes are connected to the master node through a daisy-chain.
> + Modules of this type must be listed under the 'nodes' property of the master
> + DT schema.
> +
> +properties:
> + compatible:
> + enum:
> + - adi,ad2428w-slave
> +
> + adi,tdm-mode:
> + description: The TDM mode to use
> + allOf:
> + - $ref: '/schemas/types.yaml#/definitions/uint32'
> + - enum: [2, 4, 8, 12, 16, 20, 24, 32]
> +
> + adi,tdm-slot-size:
> + description: The TDM slot size to use
> + allOf:
> + - $ref: '/schemas/types.yaml#/definitions/uint32'
> + - enum: [16, 32]
> +
> + adi,alternating-sync:
> + description: Drives the SYNC pin for I²S operation
> + type: boolean
> +
> + adi,invert-sync:
> + description: Invert the SYNC pin
> + type: boolean
> +
> + adi,early-sync:
> + description: |
> + Make the SYNC pin change one cycle before the first slot is transmitted
> + type: boolean
> +
> + adi,spread-a2b-clock:
> + description: Enables spread spectrum mode for A²B bus clocks
> + type: boolean
> +
> + adi,spread-a2b-i2s-clock:
> + description: Enables spread spectrum mode for both A²B and I²S clocks
> + type: boolean
> +
> + adi,spread-spectrum-high:
> + description: Selects high spectrum spreading mode
> + type: boolean
> +
> + upstream:
> + type: object
> + properties:
> + rx-slots:
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + description: |
> + A bitmask that describes the slots that are received by the
> + transceiver from the upstream (A) side and put into its TX output
> + framebuffers. If not specified, an empty bitmask is assumed.
> +
> + '#tx-slots':
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + description: |
> + The number of slots this transceiver contributes to the upstream
> + traffic from its RX input frame buffer
> +
> + '#forward-slots':
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + description: |
> + The number of slots this transceiver forwards from the upstream side
> + to the downstream side.
> +
> + downstream:
> + type: object
> + properties:
> + rx-slots:
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + description: |
> + A bitmask that describes the slots that are received by the
> + transceiver from the downstream (B) side and put into its TX output
> + framebuffers. If not specified, an empty bitmask is assumed.
> +
> + '#tx-slots':
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + description: |
> + The number of slots this transceiver contributes to the downstream
> + traffic from its RX input frame buffer
> +
> + '#forward-slots':
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + description: |
> + The number of slots this transceiver forwards from the downstream side
> + to the upstream side.
> +
> +required:
> + - compatible
> + - adi,tdm-mode
> + - adi,tdm-slot-size
> + - upstream
> + - downstream
> --
> 2.23.0
>