Re: [PATCH 06/11] dt-bindings: display: sun4i-drm: Add A83T HDMI pipeline

From: Rob Herring
Date: Wed Jan 03 2018 - 15:22:19 EST


On Sat, Dec 30, 2017 at 10:01:58PM +0100, Jernej Skrabec wrote:
> This commit adds all necessary compatibles and descriptions needed to
> implement A83T HDMI pipeline.
>
> Mixer is already properly described, so only compatible is added.
>
> However, A83T TCON1, which is connected to HDMI, doesn't have channel 0,
> contrary to all TCONs currently described. Because of that, TCON
> documentation is extended.
>
> A83T features Synopsys DW HDMI controller with a custom PHY which looks
> like Synopsys Gen2 PHY with few additions. Since there is no
> documentation, needed properties were found out through experimentation
> and reading BSP code.
>
> At the end, example is added for newer SoCs, which features DE2 and DW
> HDMI.
>
> Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
> ---
> .../bindings/display/sunxi/sun4i-drm.txt | 188 ++++++++++++++++++++-
> 1 file changed, 181 insertions(+), 7 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> index 9f073af4c711..3eca258096a5 100644
> --- a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> +++ b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt
> @@ -64,6 +64,40 @@ Required properties:
> first port should be the input endpoint. The second should be the
> output, usually to an HDMI connector.
>
> +DWC HDMI TX Encoder
> +-----------------------------
> +
> +The HDMI transmitter is a Synopsys DesignWare HDMI 1.4 TX controller IP
> +with Allwinner's own PHY IP. It supports audio and video outputs and CEC.
> +
> +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: value must be one of:
> + * "allwinner,sun8i-a83t-dw-hdmi"
> + - reg: two pairs of base address and size of memory-mapped region, first
> + for controller and second for PHY
> + registers.

Seems like the phy should be a separate node and use the phy binding.
You can use the phy binding even if you don't use the kernel phy
framework...

> + - reg-io-width: See dw_hdmi.txt. Shall be 1.
> + - interrupts: HDMI interrupt number
> + - clocks: phandles to the clocks feeding the HDMI encoder
> + * iahb: the HDMI bus clock
> + * isfr: the HDMI register clock
> + * tmds: the HDMI tmds clock
> + - clock-names: the clock names mentioned above
> + - resets: phandles to the reset controllers driving the encoder
> + * ctrl: the reset line for the controller
> + * phy: the reset line for the PHY
> + - reset-names: the reset names mentioned above
> +
> + - ports: A ports node with endpoint definitions as defined in
> + Documentation/devicetree/bindings/media/video-interfaces.txt. The
> + first port should be the input endpoint. The second should be the
> + output, usually to an HDMI connector.
> +
> TV Encoder
> ----------
>
> @@ -94,18 +128,17 @@ Required properties:
> * allwinner,sun7i-a20-tcon
> * allwinner,sun8i-a33-tcon
> * allwinner,sun8i-a83t-tcon-lcd
> + * allwinner,sun8i-a83t-tcon-tv
> * allwinner,sun8i-v3s-tcon
> - reg: base address and size of memory-mapped region
> - interrupts: interrupt associated to this IP
> - - clocks: phandles to the clocks feeding the TCON. Three are needed:
> + - clocks: phandles to the clocks feeding the TCON. One is needed:
> - 'ahb': the interface clocks
> - - 'tcon-ch0': The clock driving the TCON channel 0
> - resets: phandles to the reset controllers driving the encoder
> - "lcd": the reset line for the TCON channel 0
>
> - clock-names: the clock names mentioned above
> - reset-names: the reset names mentioned above
> - - clock-output-names: Name of the pixel clock created
>
> - ports: A ports node with endpoint definitions as defined in
> Documentation/devicetree/bindings/media/video-interfaces.txt. The
> @@ -119,11 +152,31 @@ Required properties:
> channel the endpoint is associated to. If that property is not
> present, the endpoint number will be used as the channel number.
>
> -On SoCs other than the A33 and V3s, there is one more clock required:
> +Following compatibles:
> + * allwinner,sun4i-a10-tcon
> + * allwinner,sun5i-a13-tcon
> + * allwinner,sun6i-a31-tcon
> + * allwinner,sun6i-a31s-tcon
> + * allwinner,sun7i-a20-tcon
> + * allwinner,sun8i-a33-tcon
> + * allwinner,sun8i-a83t-tcon-lcd
> + * allwinner,sun8i-v3s-tcon
> +have additional required properties:
> + - 'tcon-ch0': The clock driving the TCON channel 0

tcon-ch0 is a clock name, not a property.

> + - clock-output-names: Name of the pixel clock created
> +
> +For following compatibles:
> + * allwinner,sun4i-a10-tcon
> + * allwinner,sun5i-a13-tcon
> + * allwinner,sun6i-a31-tcon
> + * allwinner,sun6i-a31s-tcon
> + * allwinner,sun7i-a20-tcon
> + * allwinner,sun8i-a83t-tcon-tv
> +there is one more clock required:
> - 'tcon-ch1': The clock driving the TCON channel 1