Date:   Wed, 15 Dec 2021 14:40:43 -0600
From:   Rob Herring <robh@kernel.org>
To:     Aswath Govindraju <a-govindraju@ti.com>
Cc:     Wolfgang Grandegger <wg@grandegger.com>,
        Marc Kleine-Budde <mkl@pengutronix.de>,
        Kishon Vijay Abraham I <kishon@ti.com>,
        Vinod Koul <vkoul@kernel.org>, linux-can@vger.kernel.org,
        linux-phy@lists.infradead.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] dt-bindings: phy: ti,tcan104x-can: Document
 mux-states property
Message-ID: <YbpSy0+x/SnTYUzb@robh.at.kernel.org>
References: <20211214142908.27940-1-a-govindraju@ti.com>
 <20211214142908.27940-2-a-govindraju@ti.com>
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On Tue, Dec 14, 2021 at 07:59:07PM +0530, Aswath Govindraju wrote:
> On some boards, for routing CAN signals from controller to transceivers,
> muxes might need to be set. This can be implemented using mux-states
> property. Therefore, document the same in the respective bindings.
> 
> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
> ---
>  .../devicetree/bindings/phy/ti,tcan104x-can.yaml       | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml b/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml
> index 6107880e5246..7b9216e43b58 100644
> --- a/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml
> +++ b/Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml
> @@ -37,6 +37,15 @@ properties:
>        max bit rate supported in bps
>      minimum: 1
>  
> +  mux-states:
> +    description:
> +      mux controller node to route the signals from controller to
> +      transceiver. Two arguments can be present depending on the
> +      mux chip. If one argument is used then it represents the state
> +      to be set on the mux-chip. If there are two arguments then the
> +      first argument is the control line and the second argument is
> +      its corresponding state to be set, on the mux-chip.
> +

You are still describing how the mux-states works. What the cells 
contain and how many are opaque to this binding. Here you need to 
describe how many muxes you have and what they are controlling as that 
is what is specific to this binding. If there is only one, this boils 
down to 'maxItems: 1'. It's just like reg, interrupts, clocks, etc.

>  required:
>    - compatible
>    - '#phy-cells'
> @@ -53,4 +62,5 @@ examples:
>        max-bitrate = <5000000>;
>        standby-gpios = <&wakeup_gpio1 16 GPIO_ACTIVE_LOW>;
>        enable-gpios = <&main_gpio1 67 GPIO_ACTIVE_HIGH>;
> +      mux-states = <&mux0 1>;
>      };
> -- 
> 2.17.1
> 
>