Re: [PATCH/RFC 4/6] dt-bindings: display: rockchip: dw-hdmi: Convert binding to YAML

From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Maxime Ripard <maxime@cerno.tech>
Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>,
	devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org,
	linux-renesas-soc@vger.kernel.org,
	Rob Herring <robh+dt@kernel.org>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	Mark Yao <mark.yao@rock-chips.com>,
	Sandy Huang <hjc@rock-chips.com>, Chen-Yu Tsai <wens@csie.org>
Subject: Re: [PATCH/RFC 4/6] dt-bindings: display: rockchip: dw-hdmi: Convert binding to YAML
Date: Mon, 6 Apr 2020 14:19:27 +0300	[thread overview]
Message-ID: <20200406111927.GD4757@pendragon.ideasonboard.com> (raw)
In-Reply-To: <20200406080032.zlszhkjqmjeoa4ti@gilmour.lan>

Hi Maxime,

On Mon, Apr 06, 2020 at 10:00:32AM +0200, Maxime Ripard wrote:
> On Mon, Apr 06, 2020 at 02:39:33AM +0300, Laurent Pinchart wrote:
> > Convert the Rockchip HDMI TX text binding to YAML.
> >
> > Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> > ---
> >  .../display/rockchip/dw_hdmi-rockchip.txt     |  74 --------
> >  .../display/rockchip/rockchip,dw-hdmi.yaml    | 178 ++++++++++++++++++
> >  2 files changed, 178 insertions(+), 74 deletions(-)
> >  delete mode 100644 Documentation/devicetree/bindings/display/rockchip/dw_hdmi-rockchip.txt
> >  create mode 100644 Documentation/devicetree/bindings/display/rockchip/rockchip,dw-hdmi.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/display/rockchip/dw_hdmi-rockchip.txt b/Documentation/devicetree/bindings/display/rockchip/dw_hdmi-rockchip.txt
> > deleted file mode 100644
> > index 3d32ce137e7f..000000000000
> > --- a/Documentation/devicetree/bindings/display/rockchip/dw_hdmi-rockchip.txt
> > +++ /dev/null
> > @@ -1,74 +0,0 @@
> > -Rockchip DWC HDMI TX Encoder
> > -============================
> > -
> > -The HDMI transmitter is a Synopsys DesignWare HDMI 1.4 TX controller IP
> > -with a companion PHY IP.
> > -
> > -These DT bindings follow the Synopsys DWC HDMI TX bindings defined in
> > -Documentation/devicetree/bindings/display/bridge/dw_hdmi.txt with the
> > -following device-specific properties.
> > -
> > -
> > -Required properties:
> > -
> > -- compatible: should be one of the following:
> > -		"rockchip,rk3228-dw-hdmi"
> > -		"rockchip,rk3288-dw-hdmi"
> > -		"rockchip,rk3328-dw-hdmi"
> > -		"rockchip,rk3399-dw-hdmi"
> > -- reg: See dw_hdmi.txt.
> > -- reg-io-width: See dw_hdmi.txt. Shall be 4.
> > -- interrupts: HDMI interrupt number
> > -- clocks: See dw_hdmi.txt.
> > -- clock-names: Shall contain "iahb" and "isfr" as defined in dw_hdmi.txt.
> > -- ports: See dw_hdmi.txt. The DWC HDMI shall have a single port numbered 0
> > -  corresponding to the video input of the controller. The port shall have two
> > -  endpoints, numbered 0 and 1, connected respectively to the vopb and vopl.
> > -- rockchip,grf: Shall reference the GRF to mux vopl/vopb.
> > -
> > -Optional properties
> > -
> > -- ddc-i2c-bus: The HDMI DDC bus can be connected to either a system I2C master
> > -  or the functionally-reduced I2C master contained in the DWC HDMI. When
> > -  connected to a system I2C master this property contains a phandle to that
> > -  I2C master controller.
> > -- clock-names: See dw_hdmi.txt. The "cec" clock is optional.
> > -- clock-names: May contain "cec" as defined in dw_hdmi.txt.
> > -- clock-names: May contain "grf", power for grf io.
> > -- clock-names: May contain "vpll", external clock for some hdmi phy.
> > -- phys: from general PHY binding: the phandle for the PHY device.
> > -- phy-names: Should be "hdmi" if phys references an external phy.
> > -
> > -Optional pinctrl entry:
> > -- If you have both a "unwedge" and "default" pinctrl entry, dw_hdmi
> > -  will switch to the unwedge pinctrl state for 10ms if it ever gets an
> > -  i2c timeout.  It's intended that this unwedge pinctrl entry will
> > -  cause the SDA line to be driven low to work around a hardware
> > -  errata.
> > -
> > -Example:
> > -
> > -hdmi: hdmi@ff980000 {
> > -	compatible = "rockchip,rk3288-dw-hdmi";
> > -	reg = <0xff980000 0x20000>;
> > -	reg-io-width = <4>;
> > -	ddc-i2c-bus = <&i2c5>;
> > -	rockchip,grf = <&grf>;
> > -	interrupts = <GIC_SPI 103 IRQ_TYPE_LEVEL_HIGH>;
> > -	clocks = <&cru  PCLK_HDMI_CTRL>, <&cru SCLK_HDMI_HDCP>;
> > -	clock-names = "iahb", "isfr";
> > -	ports {
> > -		hdmi_in: port {
> > -			#address-cells = <1>;
> > -			#size-cells = <0>;
> > -			hdmi_in_vopb: endpoint@0 {
> > -				reg = <0>;
> > -				remote-endpoint = <&vopb_out_hdmi>;
> > -			};
> > -			hdmi_in_vopl: endpoint@1 {
> > -				reg = <1>;
> > -				remote-endpoint = <&vopl_out_hdmi>;
> > -			};
> > -		};
> > -	};
> > -};
> > diff --git a/Documentation/devicetree/bindings/display/rockchip/rockchip,dw-hdmi.yaml b/Documentation/devicetree/bindings/display/rockchip/rockchip,dw-hdmi.yaml
> > new file mode 100644
> > index 000000000000..8ff544ae0ac2
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/display/rockchip/rockchip,dw-hdmi.yaml
> > @@ -0,0 +1,178 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/display/rockchip/rockchip,dw-hdmi.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Rockchip DWC HDMI TX Encoder
> > +
> > +maintainers:
> > +  - Mark Yao <mark.yao@rock-chips.com>
> > +
> > +description: |
> > +  The HDMI transmitter is a Synopsys DesignWare HDMI 1.4 TX controller IP
> > +  with a companion PHY IP.
> > +
> > +allOf:
> > +  - $ref: ../bridge/synopsys,dw-hdmi.yaml#
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - rockchip,rk3228-dw-hdmi
> > +      - rockchip,rk3288-dw-hdmi
> > +      - rockchip,rk3328-dw-hdmi
> > +      - rockchip,rk3399-dw-hdmi
> > +
> > +  reg: true
> > +
> > +  reg-io-width:
> > +    const: 4
> > +
> > +  clocks:
> > +    minItems: 2
> > +    maxItems: 5
> > +    items:
> > +      - description: The bus clock for either AHB and APB
> > +      - description: The internal register configuration clock
> > +      - description: The HDMI CEC controller main clock
> > +      - description: Power for GRF IO
> > +      - description: External clock for some HDMI PHY
> > +
> > +  clock-names:
> > +    minItems: 2
> > +    maxItems: 5
> > +    items:
> > +      - const: iahb
> > +      - const: isfr
> > +      - enum:
> > +        - cec
> > +        - grf
> > +        - vpll
> > +      - enum:
> > +        - cec
> > +        - grf
> > +        - vpll
> > +      - enum:
> > +        - cec
> > +        - grf
> > +        - vpll
> 
> IIRC Rob wanted us to standardize the order of the clocks if possible,
> since it's a pain to support properly here, and your description won't
> match what you describe here either (and in general it's just a best
> practice), so if all your DTs have the same order you should just set
> that order in stone.

But how do we handle the case where any of the cec, grf and vpll clocks
can be set ? Assuming, for instance, that

	clock-names = "iahb", "isfr", "cec";
	clock-names = "iahb", "isfr", "vpll";
	clock-names = "iahb", "isfr", "cec", "vpll";

would all be valid.

> > +  ddc-i2c-bus:
> > +    $ref: /schemas/types.yaml#/definitions/phandle
> > +    description:
> > +      The HDMI DDC bus can be connected to either a system I2C master or the
> > +      functionally-reduced I2C master contained in the DWC HDMI. When connected
> > +      to a system I2C master this property contains a phandle to that I2C
> > +      master controller.
> > +
> > +  interrupts: true
> > +
> > +  phys:
> > +    maxItems: 1
> > +    description: The HDMI PHY
> > +
> > +  phy-names:
> > +    const: hdmi
> > +
> > +  pinctrl-0: true
> > +  pinctrl-1: true
> 
> These two are already set by the tools on any schemas (up to
> pinctrl-255 actually).

Thank you for the information. I'll drop them.

-- 
Regards,

Laurent Pinchart