Re: [PATCH 03/16] dt-bindings: spi: Add spi peripheral specific property

[Mark Brown <broonie@kernel.org>]

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On Fri, Jan 06, 2023 at 12:07:55PM -0800, William Zhang wrote:

> brcm,no-clk-gate is a Broadcom Broadband HS SPI controller specific
> property for certain SPI device such as Broadcom ISI voice daughtercard
> to work properly. It disables the clock gating feature when the chip
> select is deasserted for any device that wants to keep the clock
> running.

Why would this property be Broadcom specific?  Other devices could in
theory implement this.

> +properties:
> +  brcm,no-clk-gate:
> +    $ref: /schemas/types.yaml#/definitions/flag
> +    description:
> +      Some SPI device such as Broadcom ISI based voice daughtercard requires SPI
> +      clock running even when chip select is deasserted. By default the
> +      controller turns off or gate the clock when cs is not active to save
> +      power. This flag tells the controller driver to keep the clock running
> +      when chip select is not active.

This seems problematic with any host controlled chip select support...

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