On 10/06/2023 07:35, Binbin Zhou wrote: > On Sat, Jun 10, 2023 at 12:49 AM Krzysztof Kozlowski > <krzysztof.kozlowski@xxxxxxxxxx> wrote: >> >> On 08/06/2023 04:55, Binbin Zhou wrote: >>> Add Loongson LS2X APB DMA controller binding with DT schema >>> format using json-schema. >>> >>> Signed-off-by: Binbin Zhou <zhoubinbin@xxxxxxxxxxx> >>> Reviewed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> >> >> >>> +properties: >>> + compatible: >>> + oneOf: >>> + - const: loongson,ls2k1000-apbdma >>> + - items: >>> + - const: loongson,ls2k0500-apbdma >>> + - const: loongson,ls2k1000-apbdma >>> + >>> + reg: >>> + maxItems: 1 >>> + >>> + interrupts: >>> + maxItems: 1 >>> + >>> + "#dma-cells": >>> + const: 1 >>> + >>> + dma-channels: >>> + const: 1 >> >> If it is const, why do you need it? >> > Hi Krzysztof: > > IMO, although it is a single-channel DMAC, the "dma-channels" are > still needed for a more comprehensive description of the hardware. How does it describe more the hardware if it is obvious and always the same? If so, why you didn't add properties like reg-io-width, dma-requests, clock-frequency, clocks (BTW, this actually is missing), dma-channel-mask and hundreds of others? No, drop, it does not make sense. Best regards, Krzysztof