Re: [PATCH v4 2/6] dt-bindings: audio-graph-card: Add plls and sysclks properties

On 13/01/2021 15:22, Rob Herring wrote:

On Fri, Jan 08, 2021 at 04:04:57PM +0000, Richard Fitzgerald wrote:

...

The audio-graph-card driver has properties for configuring the clocking for DAIs within a component, but is missing properties for setting up the PLLs and sysclks of the component.

This patch adds the two new properties 'plls' and 'sysclks' so that the audio-graph-driver can fully configure the component clocking.

I'm not sure this makes sense to be generic, but if so, we already have the clock binding and should use (and possibly extend) that.

This appears to all be configuration of clocks within the codec, so these properties belong in the codec or cpu nodes.

audio-graph-card doesn't have codec or cpu nodes. Those were in simple-card but are replaced in audio-graph-card by a simple phandle array forming a graph.

I could assume that all clock settings apply to the codec and that there is only ever one codec in an audio-graph-card configuration.

...

Signed-off-by: Richard Fitzgerald rf@opensource.cirrus.com

.../bindings/sound/audio-graph.yaml | 46 +++++++++++++++++++ 1 file changed, 46 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/audio-graph.yaml b/Documentation/devicetree/bindings/sound/audio-graph.yaml index 4b46794e5153..9e0819205a17 100644 --- a/Documentation/devicetree/bindings/sound/audio-graph.yaml +++ b/Documentation/devicetree/bindings/sound/audio-graph.yaml @@ -39,6 +39,52 @@ properties: mic-det-gpio: maxItems: 1

• plls:
• description: |

•  A list of component pll settings. There are 4 cells per PLL setting:
  

•    - phandle to the node of the codec or cpu component,
  

•    - component PLL id,
  

•    - component clock source id,
  

•    - frequency (in Hz) of the PLL output clock.
  

assigned-clocks binding can set frequencies and parent clocks.

'pll' is too specific to the implementation. You may want to configure the freq and parent of something that's not a pll.

...

•  The PLL id and clock source id are specific to the particular component
  

•  so see the relevant component driver for the ids. Typically the
  

•  clock source id indicates the pin the source clock is connected to.
  

•  The same phandle can appear in multiple entries so that several plls
  

•  can be set in the same component.
  

• $ref: /schemas/types.yaml#/definitions/phandle-array
• plls-clocks:
• $ref: /schemas/types.yaml#/definitions/non-unique-string-array
• description: |

•  A list of clock names giving the source clock for each setting
  

•  in the plls property.
  

• sysclks:
• description: |

•  A list of component sysclk settings. There are 4 cells per sysclk
  

•  setting:
  

•    - phandle to the node of the codec or cpu component,
  

•    - component sysclk id,
  

•    - component clock source id,
  

•    - direction of the clock: 0 if the clock is an input to the component,
  

•      1 if it is an output.
  

A clock provider and consumer would provide the direction.

...

•  The sysclk id and clock source id are specific to the particular
  

•  component so see the relevant component driver for the ids. Typically
  

•  the clock source id indicates the pin the source clock is connected to.
  

•  The same phandle can appear in multiple entries so that several sysclks
  

•  can be set in the same component.
  

• $ref: /schemas/types.yaml#/definitions/phandle-array
• sysclks-clocks:
• $ref: /schemas/types.yaml#/definitions/non-unique-string-array
• description: |

•  A list of clock names giving the source clock for each setting
  

•  in the sysclks property.
  

+dependencies:

• plls: [ plls-clocks ]
• sysclks: [ sysclks-clocks ]
• required:
  • dais

-- 2.20.1