Re: [PATCH 2/2] dt-bindings: mediatek: mt8195: add clock property to sound node

On Thu, 2021-12-16 at 13:06 -0600, Rob Herring wrote:

On Wed, Dec 15, 2021 at 02:58:35PM +0800, Trevor Wu wrote:

...

clocks and clock-names are added to provide MCLK phandle for sound card.

Signed-off-by: Trevor Wu trevor.wu@mediatek.com

.../bindings/sound/mt8195-mt6359-rt1011-rt5682.yaml | 12 ++++++++++++ .../bindings/sound/mt8195-mt6359-rt1019-rt5682.yaml | 12 ++++++++++++ 2 files changed, 24 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/mt8195-mt6359- rt1011-rt5682.yaml b/Documentation/devicetree/bindings/sound/mt8195-mt6359-rt1011- rt5682.yaml index cf6ad7933e23..b57c856d0cf3 100644 --- a/Documentation/devicetree/bindings/sound/mt8195-mt6359-rt1011- rt5682.yaml +++ b/Documentation/devicetree/bindings/sound/mt8195-mt6359-rt1011- rt5682.yaml @@ -32,11 +32,21 @@ properties: $ref: "/schemas/types.yaml#/definitions/phandle" description: The phandle of MT8195 HDMI codec node.

• clocks:
• items:

•  - description: phandle and clock specifier for codec MCLK.
  

• clock-names:
• items:

•  - const: i2so1_mclk
  

additionalProperties: false

required:

• compatible
• mediatek,platform

• • clocks
• • clock-names

examples:

• |

@@ -44,6 +54,8 @@ examples: sound: mt8195-sound { compatible = "mediatek,mt8195_mt6359_rt1011_rt5682"; mediatek,platform = <&afe>;

•    clocks = <&topckgen 235>; //CLK_TOP_APLL12_DIV2
  

•    clock-names = "i2so1_mclk";
     pinctrl-names = "default";
     pinctrl-0 = <&aud_pins_default>;
  

  };

diff --git a/Documentation/devicetree/bindings/sound/mt8195-mt6359- rt1019-rt5682.yaml b/Documentation/devicetree/bindings/sound/mt8195-mt6359-rt1019- rt5682.yaml index 8f177e02ad35..e4720f76f66b 100644 --- a/Documentation/devicetree/bindings/sound/mt8195-mt6359-rt1019- rt5682.yaml +++ b/Documentation/devicetree/bindings/sound/mt8195-mt6359-rt1019- rt5682.yaml @@ -42,11 +42,21 @@ properties: A list of the desired dai-links in the sound card. Each entry is a name defined in the machine driver.

• clocks:
• items:

•  - description: phandle and clock specifier for codec MCLK.
  

• clock-names:
• items:

•  - const: i2so1_mclk
  

additionalProperties: false

required:

• compatible
• mediatek,platform

• • clocks
• • clock-names

examples:

• |

@@ -54,6 +64,8 @@ examples: sound: mt8195-sound { compatible = "mediatek,mt8195_mt6359_rt1019_rt5682"; mediatek,platform = <&afe>;

•    clocks = <&topckgen 235>; //CLK_TOP_APLL12_DIV2
  

•    clock-names = "i2so1_mclk";
  

Being a virtual node, how does it have clocks? This belongs in the h/w device that consumes the clock.

Hi Rob,

I also found the same usages in some bindings from nvidia, like[1].

Based on my understanding, it seems not to be recommended now and clocks should only be used for a real hw node, is it correct?

If yes, I will try other way to get the clock I need in alsa machine driver.

[1] https://elixir.bootlin.com/linux/v5.16-rc5/source/Documentation/devicetree/b...

Thanks, Trevor

...

     pinctrl-0 = <&aud_pins_default>;
 };

-- 2.18.0