Re: [PATCH v4 2/4] dt-bindings: sound: add rockchip i2s-tdm binding

On Sat, Sep 04, 2021 at 01:15:34AM +0200, Nicolas Frattaroli wrote:

• rockchip,frame-width:
• $ref: /schemas/types.yaml#/definitions/uint32
• default: 64
• minimum: 32
• maximum: 512
• description:

•  Width of a frame, usually slot width multiplied by number of slots.
  

•  Must be even.
  

Why is this in the binding? This is normally configured by the machine driver setting the TDM slots, not through DT.

• rockchip,mclk-calibrate:
• description:

•  Switch between two root clocks depending on the audio sample rate.
  

•  For integer multiples of 8000 (e.g. 48000 Hz), mclk_root0 is used.
  

•  For integer multiples of 11025 (e.g. 44100 Hz), mclk_root1 is used.
  

• type: boolean

Why would we not want to do this, and assuming it's to do with availability can't we detect it simply through seeing if both MCLKs are available?

• rockchip,tdm-fsync-half-frame:
• description: Whether to use half frame fsync.
• type: boolean

Why is this not part of the normal bus format configuration? I don't know what this is but it sounds a lot like I2S mode...