On 20/06/2022 08:59, Chunfeng Yun wrote: > On Sun, 2022-06-19 at 14:05 +0200, Krzysztof Kozlowski wrote: >> On 19/06/2022 09:46, Chunfeng Yun wrote: >>> On Fri, 2022-06-17 at 18:25 -0700, Krzysztof Kozlowski wrote: >>>> On 17/06/2022 15:29, Nícolas F. R. A. Prado wrote: >>>>> The current clock list in the binding doesn't allow for one of >>>>> the >>>>> optional clocks to be missing and a subsequent clock to be >>>>> present. >>>>> An >>>>> example where this is an issue is in mt8192.dtsi, which has >>>>> "sys_ck", >>>>> "ref_ck", "xhci_ck" and would cause dtbs_check warnings. >>>>> >>>>> Change the clock list in a way that allows the middle optional >>>>> clocks to >>>>> be missing, while still guaranteeing a fixed order. The >>>>> "ref_ck" is >>>>> kept >>>>> as a const even though it is optional for simplicity, since it >>>>> is >>>>> present in all current dts files. >>>>> >>>>> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx> >>>>> --- >>>>> >>>>> .../devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 9 >>>>> +++++++-- >>>>> 1 file changed, 7 insertions(+), 2 deletions(-) >>>>> >>>>> diff --git >>>>> a/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>> xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>> xhci.yaml >>>>> index 63cbc2b62d18..99a1b233ec90 100644 >>>>> --- a/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>> xhci.yaml >>>>> +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk- >>>>> xhci.yaml >>>>> @@ -80,8 +80,13 @@ properties: >>>>> items: >>>>> - const: sys_ck # required, the following ones are >>>>> optional >>>>> - const: ref_ck >>>>> - - const: mcu_ck >>>>> - - const: dma_ck >>>>> + - enum: >>>>> + - mcu_ck >>>>> + - dma_ck >>>>> + - xhci_ck >>>>> + - enum: >>>>> + - dma_ck >>>>> + - xhci_ck >>>>> - const: xhci_ck >>>> >>>> You allow now almost any order here, including incorrect like >>>> sys,ref,xhci,xhci,xhci. >>>> >>>> The order of clocks has to be fixed and we cannot allow >>>> flexibility. >>>> Are >>>> you sure that these clocks are actually optional (not wired to >>>> the >>>> device)? >>> >>> In fact, these optional clocks are fixed, due to no gates are >>> provided, >>> SW can't control them by CCF; >>> In this case, I usually use a fixed clock, or ignore it. >> >> But in some versions these clocks are controllable or not? > Some SoCs are controllable, some ones are not (fixed clock). Thanks for confirming. Then I would prefer to make these clocks required (not optional) and always provide them - via common clock framework or fixed-clock. Best regards, Krzysztof
