Re: [PATCH v2 1/4] dt-bindings: clock: si5351: convert to yaml

From: Rob Herring
Date: Wed Oct 04 2023 - 10:39:45 EST


On Wed, Oct 04, 2023 at 08:35:27AM +0200, Alvin Šipraga wrote:
> From: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
>
> The following additional properties are described:
>
> - clock-names
> - clock-frequency of the clkout child nodes
>
> In order to suppress warnings from the DT schema validator, the clkout
> child nodes are prescribed names clkout@[0-7] rather than clkout[0-7].
> The latter form is still admissible but the example has been changed to
> use the former.
>
> The example is refined as follows:
>
> - correct the usage of property pll-master -> silabs,pll-master
> - give an example of how the silabs,pll-reset property can be used
>
> I made myself maintainer of the file as I cannot presume that anybody
> else wants the responsibility.
>
> Cc: Sebastian Hesselbarth <sebastian.hesselbarth@xxxxxxxxx>
> Cc: Rabeeh Khoury <rabeeh@xxxxxxxxxxxxx>
> Signed-off-by: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
> ---
> .../bindings/clock/silabs,si5351.txt | 126 ---------
> .../bindings/clock/silabs,si5351.yaml | 253 ++++++++++++++++++
> 2 files changed, 253 insertions(+), 126 deletions(-)
> delete mode 100644 Documentation/devicetree/bindings/clock/silabs,si5351.txt
> create mode 100644 Documentation/devicetree/bindings/clock/silabs,si5351.yaml

[...]

> diff --git a/Documentation/devicetree/bindings/clock/silabs,si5351.yaml b/Documentation/devicetree/bindings/clock/silabs,si5351.yaml
> new file mode 100644
> index 000000000000..400c8cec2a3a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/silabs,si5351.yaml
> @@ -0,0 +1,253 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/clock/silabs,si5351.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Silicon Labs Si5351A/B/C programmable I2C clock generators
> +
> +description: |
> + The Silicon Labs Si5351A/B/C are programmable I2C clock generators with up to
> + 8 outputs. Si5351A also has a reduced pin-count package (10-MSOP) where only 3
> + output clocks are accessible. The internal structure of the clock generators
> + can be found in [1].
> +
> + [1] Si5351A/B/C Data Sheet
> + https://www.skyworksinc.com/-/media/Skyworks/SL/documents/public/data-sheets/Si5351-B.pdf
> +
> +maintainers:
> + - Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
> +
> +properties:
> + compatible:
> + enum:
> + - silabs,si5351a # Si5351A, 20-QFN package
> + - silabs,si5351a-msop # Si5351A, 10-MSOP package
> + - silabs,si5351b # Si5351B, 20-QFN package
> + - silabs,si5351c # Si5351C, 20-QFN package
> +
> + reg:
> + enum:
> + - 0x60
> + - 0x61
> +
> + "#address-cells":
> + const: 1
> +
> + "#size-cells":
> + const: 0
> +
> + "#clock-cells":
> + const: 1
> +
> + silabs,pll-source:
> + $ref: /schemas/types.yaml#/definitions/uint32-matrix
> + description: |
> + A list of cell pairs containing a PLL index and its source. Allows to
> + overwrite clock source of the internal PLLs.
> + minItems: 1

The minimum is 1 by default (can't have 0).

> + items:
> + items:
> + - description: PLL A (0) or PLL B (1)
> + enum: [ 0, 1 ]
> + - description: PLL source, XTAL (0) or CLKIN (1, Si5351C only).
> + enum: [ 0, 1 ]
> +
> +patternProperties:
> + "^clkout@[0-7]$":
> + type: object
> +
> + properties:
> + reg:
> + $ref: /schemas/types.yaml#/definitions/uint32

reg already has a type. Drop.

> + description: Clock output number.
> +
> + clock-frequency: true
> +
> + silabs,clock-source:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: |
> + Source clock of the this output's divider stage.
> +
> + 0 - use multisynth N for this output, where N is the output number
> + 1 - use either multisynth 0 (if output number is 0-3) or multisynth 4
> + (otherwise) for this output
> + 2 - use XTAL for this output
> + 3 - use CLKIN for this output (Si5351C only)
> +
> + silabs,drive-strength:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + enum: [ 2, 4, 6, 8 ]
> + description: Output drive strength in mA.
> +
> + silabs,multisynth-source:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + enum: [ 0, 1 ]
> + description: |

Don't need '|' if no formatting to preserve.

> + Source PLL A (0) or B (1) for the corresponding multisynth divider.
> +
> + silabs,pll-master:
> + type: boolean
> + description: |
> + The frequency of the source PLL is allowed to be changed by the
> + multisynth when setting the rate of this clock output.
> +
> + silabs,pll-reset:
> + type: boolean
> + description: Reset the source PLL when enabling this clock output.
> +
> + silabs,disable-state:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + enum: [ 0, 1, 2, 3 ]
> + description: |
> + Clock output disable state. The state can be one of:
> +
> + 0 - clock output is driven LOW when disabled
> + 1 - clock output is driven HIGH when disabled
> + 2 - clock output is FLOATING (HIGH-Z) when disabled
> + 3 - clock output is never disabled
> +
> + allOf:
> + - if:
> + properties:
> + compatible:
> + contains:
> + const: silabs,si5351a-msop
> + then:
> + properties:
> + reg:
> + minimum: 0

The minimum is already 0. Drop.

> + maximum: 2
> + else:
> + properties:
> + reg:
> + minimum: 0
> + maximum: 7
> +
> + - if:
> + properties:
> + compatible:
> + contains:
> + const: silabs,si5351c
> + then:
> + properties:
> + silabs,clock-source:
> + enum: [ 0, 1, 2, 3 ]
> + else:
> + properties:
> + silabs,clock-source:
> + enum: [ 0, 1, 2 ]
> + required:
> + - reg
> +
> + additionalProperties: false

Move this next to 'type: object'

> +
> +allOf:
> + - $ref: /schemas/clock/clock.yaml

Don't need this.

> + - if:
> + properties:
> + compatible:
> + contains:
> + enum:
> + - silabs,si5351a
> + - silabs,si5351a-msop
> + - silabs,si5351b

Isn't this just the 'else' for the next one? Or more parts are coming?

> + then:
> + properties:
> + clocks:
> + minItems: 1
> + maxItems: 1
> + clock-names:
> + items:
> + - const: xtal
> +
> + - if:
> + properties:
> + compatible:
> + contains:
> + const: silabs,si5351c
> + then:
> + properties:
> + clocks:
> + minItems: 1
> + maxItems: 2
> + clock-names:
> + minItems: 1
> + items:
> + - const: xtal
> + - const: clkin

Define clocks and clock-names at the top level and just use
minItems/maxItems in the if/then schemas.

> +
> +required:
> + - reg
> + - "#address-cells"
> + - "#size-cells"
> + - "#clock-cells"
> + - clocks
> + - clock-names
> +
> +unevaluatedProperties: false
> +
> +examples:
> + - |
> + i2c {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + clock-generator@60 {
> + compatible = "silabs,si5351a-msop";
> + reg = <0x60>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + #clock-cells = <1>;
> +
> + /* Connect XTAL input to 25MHz reference */
> + clocks = <&ref25>;
> + clock-names = "xtal";
> +
> + /* Use XTAL input as source of PLL0 and PLL1 */
> + silabs,pll-source = <0 0>, <1 0>;
> +
> + /*
> + * Overwrite CLK0 configuration with:
> + * - 8 mA output drive strength
> + * - PLL0 as clock source of multisynth 0
> + * - Multisynth 0 as clock source of output divider
> + * - Multisynth 0 can change PLL0
> + * - Set initial clock frequency of 74.25MHz
> + */
> + clkout@0 {
> + reg = <0>;
> + silabs,drive-strength = <8>;
> + silabs,multisynth-source = <0>;
> + silabs,clock-source = <0>;
> + silabs,pll-master;
> + clock-frequency = <74250000>;
> + };
> +
> + /*
> + * Overwrite CLK1 configuration with:
> + * - 4 mA output drive strength
> + * - PLL1 as clock source of multisynth 1
> + * - Multisynth 1 as clock source of output divider
> + * - Multisynth 1 can change PLL1
> + * - Reset PLL1 when enabling this clock output
> + */
> + clkout@1 {
> + reg = <1>;
> + silabs,drive-strength = <4>;
> + silabs,multisynth-source = <1>;
> + silabs,clock-source = <0>;
> + silabs,pll-master;
> + silabs,pll-reset;
> + };
> +
> + /*
> + * Overwrite CLK2 configuration with:
> + * - XTAL as clock source of output divider
> + */
> + clkout@2 {
> + reg = <2>;
> + silabs,clock-source = <2>;
> + };
> + };
> + };
> --
> 2.42.0
>