Re: [PATCH 1/4] dt-bindings: aspeed: Add UART controller

From: Krzysztof Kozlowski
Date: Fri Feb 10 2023 - 04:12:42 EST


On 10/02/2023 08:26, Chia-Wei Wang wrote:
> Add dt-bindings for Aspeed UART controller.

Describe the hardware. What's the difference against existing Aspeed
UART used everywhere?

>
> Signed-off-by: Chia-Wei Wang <chiawei_wang@xxxxxxxxxxxxxx>
> ---
> .../bindings/serial/aspeed,uart.yaml | 81 +++++++++++++++++++
> 1 file changed, 81 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/serial/aspeed,uart.yaml

Filename: aspeed,ast2600-uart.yaml
(unless you are adding here more compatibles, but your const suggests
that it's not going to happen)

>
> diff --git a/Documentation/devicetree/bindings/serial/aspeed,uart.yaml b/Documentation/devicetree/bindings/serial/aspeed,uart.yaml
> new file mode 100644
> index 000000000000..10c457d6a72e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/serial/aspeed,uart.yaml
> @@ -0,0 +1,81 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/serial/aspeed,uart.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Aspeed Universal Asynchronous Receiver/Transmitter

This title matches other Aspeed UARTs, so aren't you duplicating bindings?

> +
> +maintainers:
> + - Chia-Wei Wang <chiawei_wang@xxxxxxxxxxxxxx>
> +
> +allOf:
> + - $ref: serial.yaml#
> +
> +description: |
> + The Aspeed UART is based on the basic 8250 UART and compatible
> + with 16550A, with support for DMA
> +
> +properties:
> + compatible:
> + const: aspeed,ast2600-uart
> +
> + reg:
> + description: The base address of the UART register bank

Drop description

> + maxItems: 1
> +
> + clocks:
> + description: The clock the baudrate is derived from
> + maxItems: 1
> +
> + interrupts:
> + description: The IRQ number of the device

Drop description

> + maxItems: 1
> +
> + dma-mode:
> + type: boolean
> + description: Enable DMA

Drop property. DMA is enabled on presence of dmas.

> +
> + dma-channel:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: The channel number to be used in the DMA engine

That's not a correct DMA property. dmas and dma-names
git grep dma -- Documentation/devicetree/bindings/


> +
> + virtual:
> + type: boolean
> + description: Indicate virtual UART

Virtual means not existing in real world? We do not describe in DTS
non-existing devices. Drop entire property.

> +
> + sirq:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: The serial IRQ number on LPC bus interface

Drop entire property.

> +
> + sirq-polarity:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: The serial IRQ polarity on LPC bus interface

Drop entire property.

> +
> + pinctrl-0: true
> +
> + pinctrl_names:
> + const: default


Drop both, you do no not need them.

> +
> +required:
> + - compatible
> + - reg
> + - clocks
> + - interrupts
> +
> +unevaluatedProperties: false
> +

Best regards,
Krzysztof