Re:Re: [PATCH v5 06/12] dt-bindings: serial: add Ambarella CV75 UART

[zl020895 <zl020895@163.com>]

Thanks for the review.

I did not copy a specific SoC UART binding. I followed the common
8250 OF properties (reg-shift / reg-io-width). I will drop them 
and hardcode the access in the driver.

Best regards,
Long Zhao

At 2026-08-19 15:37:02, "Krzysztof Kozlowski" <krzk@kernel.org> wrote:
>On 18/08/2026 12:31, Long Zhao via B4 Relay wrote:
>> From: Long Zhao <longzhao@ambarella.com>
>> 
>> Document the Ambarella CV75 on-chip UART controller binding for early
>> console bring-up. The binding requires a single RCT clock input and
>> fixed 32-bit register access via reg-shift and reg-io-width.
>> 
>> Signed-off-by: Long Zhao <longzhao@ambarella.com>
>> ---
>>  .../bindings/serial/ambarella,cv75-uart.yaml       | 56 ++++++++++++++++++++++
>>  1 file changed, 56 insertions(+)
>> 
>> diff --git a/Documentation/devicetree/bindings/serial/ambarella,cv75-uart.yaml b/Documentation/devicetree/bindings/serial/ambarella,cv75-uart.yaml
>> new file mode 100644
>> index 000000000000..223c84bf460d
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/serial/ambarella,cv75-uart.yaml
>> @@ -0,0 +1,56 @@
>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/serial/ambarella,cv75-uart.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Ambarella CV75 UART
>> +
>> +maintainers:
>> +  - Long Zhao <longzhao@ambarella.com>
>> +
>> +allOf:
>> +  - $ref: serial.yaml#
>> +
>> +properties:
>> +  compatible:
>> +    const: ambarella,cv75-uart
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  interrupts:
>> +    maxItems: 1
>> +
>> +  clocks:
>> +    maxItems: 1
>> +
>> +  reg-shift:
>> +    const: 2
>> +
>> +  reg-io-width:
>> +    const: 4
>
>Both properties are redundant. Const properties are pointless. Did you
>take any existing code as example of this? If so which, so we can fix it?
>
>Best regards,
>Krzysztof