Hi Arnd, On 2016/1/13 6:51, Arnd Bergmann wrote: > On Tuesday 12 January 2016 17:28:05 xuejiancheng wrote: >>>>>>> >>>>>> Not yet. >>>>>> Arnd Bergmann and Rob Herring all suggested adding a specific compatible string >>>>>> with the SOC name. This binding is just used for describing the compatible string now. >>>>>> When more functions on hi3519 SOC are added later, the specific driver will be also >>>>>> needed. >>>>> >>>>> Save this binding until it has more functionality. We here "I'll add >>>>> to this later" all too often. >>>>> >>>> >>>> In the hi3519.dtsi file, there is a system-controller device node described like below: >>>> sysctrl: system-controller@12010000 { >>>> compatible = "hisilicon,hi3519-sysctrl", "syscon"; >>>> reg = <0x12010000 0x1000>; >>>> }; >>>> Do you mean that I should remove "hisilicon,hi3519-sysctrl" and just use "syscon" as the >>>> compatible string? >>> >>> Where is this compatible string _used_? >>> >>>> If I want to add "hisilicon,hi3519-sysctrl" for hi3519. where should I put this binding? >>>> Could you give some suggestions? Thank you very much! >>> >>> If you're not using the compatible i.e. the device doesn't have its >>> own driver yet, then there is no need to supply the binding at all, is >>> there? >>> >> >> OK. Thank you. >> > > Sorry for stepping in late here. I still think that every syscon device should > come with a specific compatible string, so we have the option of creating a > driver later on, and I'd like to see a binding document that lists those strings > (which I believe exists here). > > It's really hard to add compatible strings later on, anything else we can > work around by keying off that string and adding a workaround in the kernel. > Is it OK if I put this binding document into the directory "Documentation/devicetree/bindings/arm/hisilicon"? Thank you. > Arnd > > . > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html