[PATCH v2 2/5] dt-bindings: scsi: ufs: add document for hi3660-ufs

[subhashj@codeaurora.org (Subhash Jadavani)]

On 2017-06-22 04:51, Arnd Bergmann wrote:
> On Thu, Jun 22, 2017 at 1:44 PM, Bu Tao <butao@huawei.com> wrote:
>> ? 2017/6/17 5:51, Arnd Bergmann ??:
>>> On Fri, Jun 16, 2017 at 8:51 AM, Bu Tao <butao@hisilicon.com> wrote:
>>>> +Optional properties for board device:
>>>> +- ufs-hi3660-use-rate-B                : specifies UFS rate-B
>>>> +- ufs-hi3660-broken-fastauto   : specifies no fastauto
>>>> +- ufs-hi3660-use-HS-GEAR3      : specifies UFS HS-GEAR3
>>>> +- ufs-hi3660-use-HS-GEAR2      : specifies UFS HS-GEAR2
>>>> +- ufs-hi3660-use-HS-GEAR1      : specifies UFS HS-GEAR1
>>>> +- ufs-hi3660-broken-clk-gate-bypass    : specifies no clk-gate
>>>> +- ufs-hi3660-use-one-line      : specifies UFS use one line work
>>>> +- reset-gpio                   : specifies to reset devices
>>> 
>>> 
>>> Some of these sound rather generic and might apply to UFS 
>>> implementations
>>> other than hi3660, so I'd suggest adding them to the base ufs binding 
>>> with
>>> a generic name instead.
>>> 
>>> Any DT properties that might be useful across multiple 
>>> implementations
>>> should be parsed in generic code that gets called by the individual
>>> drivers,
>>> and then the properties that are specific to the integration work 
>>> done by
>>> hisilicon should be prefixed with "hisilicon,", but not normally with 
>>> the
>>> SoC name: it is quite possible that another SoC will be derived from 
>>> this
>>> chip and it should reuse the properties.
>> 
>> 
>> I do not know wheher other SoC need to use the optional properties as
>> abover. So here the name of the optional properties has "hi3660".
> 
> They should not have "hi3660" in their names either way, independent
> of where they are used.


Yes, i agree with Arnd that SoCs might also need these so please make 
these properties generic (put them under 
Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt) and also move 
their parsing code in generic driver (ufshcd.c or ufshcd-pltfrm.c).

> 
>>> (note: this is different from the value of the "compatible" property 
>>> that
>>> is meant to be as specific as possible".
>>> 
>>> Also, please clarify how your binding relates to the ufshcd binding
>>> in Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt: does
>>> hi3660 implement any registers that are shared with ufshcd, or does
>>> it use the same physical interface with a different register set?
>> 
>> No, only show how to use the dt-binding for hi3660 SoC
> 
> My question was about the hardware: does hi3660 implement ufshcd
> or not?
> 
>       Arnd

-- 
The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project