Re: [PATCH 1/3] dt-bindings: display: bridge: add sam9x7-lvds compatible

From: Krzysztof Kozlowski
Date: Mon Jan 22 2024 - 12:06:35 EST


On 22/01/2024 09:29, Dharma Balasubiramani wrote:
> Add the 'sam9x7-lvds' compatible binding, which describes the
> Low Voltage Differential Signaling (LVDS) Controller found on Microchip's
> sam9x7 series System-on-Chip (SoC) devices. This binding will be used to
> define the properties and configuration for the LVDS Controller in DT.
>
> Signed-off-by: Dharma Balasubiramani <dharma.b@xxxxxxxxxxxxx>
> ---
> .../display/bridge/microchip,sam9x7-lvds.yaml | 59 +++++++++++++++++++
> 1 file changed, 59 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/display/bridge/microchip,sam9x7-lvds.yaml
>
> diff --git a/Documentation/devicetree/bindings/display/bridge/microchip,sam9x7-lvds.yaml b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x7-lvds.yaml
> new file mode 100644
> index 000000000000..8c2c5b858c85
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/bridge/microchip,sam9x7-lvds.yaml
> @@ -0,0 +1,59 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/bridge/microchip,sam9x7-lvds.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Microchip SAM9X7 LVDS Controller

What is the "X"?

> +
> +maintainers:
> + - Dharma Balasubiramani <dharma.b@xxxxxxxxxxxxx>
> +
> +description: |

Do not need '|' unless you need to preserve formatting.

> + The Low Voltage Differential Signaling Controller (LVDSC) manages data
> + format conversion from the LCD Controller internal DPI bus to OpenLDI
> + LVDS output signals. LVDSC functions include bit mapping, balanced mode
> + management, and serializer.
> +
> +properties:
> + compatible:
> + const: microchip,sam9x7-lvds

What is "x"? Wildcard? Then no, don't use it and instead use proper SoC
version number.

> +
> + reg:
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> + clocks:
> + items:
> + - description: Peripheral Bus Clock
> +
> + clock-names:
> + items:
> + - const: pclk
> + - const: gclk
> + minItems: 1

No, you just said you have one clock.

> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> + - clocks
> + - clock-names
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/clock/at91.h>
> + #include <dt-bindings/dma/at91.h>
> + #include <dt-bindings/interrupt-controller/arm-gic.h>

This header is not used. Include only used ones (and missing interrupt).

> +
> + lvds-controller@f8060000 {
> + compatible = "microchip,sam9x7-lvds";
> + reg = <0xf8060000 0x100>;
> + interrupts = <56 IRQ_TYPE_LEVEL_HIGH 0>;

What is "0"?

> + clocks = <&pmc PMC_TYPE_PERIPHERAL 56>;
> + clock-names = "pclk";
> + };

Best regards,
Krzysztof