Re: [PATCH v3 1/2] dt-bindings: add device tree binding for Allwinner XR819 SDIO Wi-Fi

From: Kalle Valo
Date: Mon Oct 16 2017 - 08:58:32 EST


icenowy@xxxxxxx writes:

>>>>> > > Like I asked already last time, AFAICS there is no upstream xr819
>>>>> > > wireless driver in drivers/net/wireless directory. Do we still
>>>> accept
>>>>> > > bindings like this for out-of-tree drivers?
>>>>> >
>>>>> > See esp8089.
>>>>> >
>>>>> > There's also no in-tree driver for it.
>>>>>
>>>>> The question is whether we should. The above might be a precedent,
>>>> but it
>>>>> may not necessarily be the way to go. The commit message for esp8089
>>>> seems
>>>>> to hint that there is intent to have an in-tree driver:
>>>>>
>>>>> """
>>>>> Note that at this point there only is an out of tree driver for
>>>> this
>>>>> hardware, there is no clear timeline / path for merging this.
>>>> Still
>>>>> I believe it would be good to specify the binding for this in
>>>> tree
>>>>> now, so that any future migration to an in tree driver will not
>>>> cause
>>>>> compatiblity issues.
>>>>>
>>>>> Cc: Icenowy Zheng <icenowy@xxxxxxxx>
>>>>> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
>>>>> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
>>>>> """
>>>>>
>>>>> Regardless the bindings are in principle independent of the kernel
>>>> and just
>>>>> describing hardware. I think there have been discussions to move the
>>>>> bindings to their own repository, but apparently it was decided
>>>> otherwise.
>>>>
>>>> Yeah, I guess especially how it could be merged with the cw1200
>>>> driver
>>>> would be very relevant to that commit log.
>>>
>>> The cw1200 driver seems to still have some legacy platform
>>> data. Maybe they should also be convert to DT.
>>> (Or maybe compatible = "allwinner,xr819" is enough, as
>>> xr819 is a specified variant of cw1200 family)
>>
>> Ah, so the upstream cw1200 driver supports xr819? Has anyone tested
>> that? Or does cw1200 more changes than just adding the DT support?
>
> The support of XR819 in CW1200 driver is far more difficult than I
> imagined -- the codedrop used in the mainlined CW1200 driver seems to
> be so old that it's before XR819 (which seems to be based on CW1160),
> and there's a large number of problems to adapt it to a modern CW1200
> variant.
>
> P.S. could you apply this device tree binding patch now?

As I haven't seen any consensus that applying bindings document for
out-of-tree drivers is ok so at least I'm not taking this. Though not
sure what DT maintainers are planning to do.

--
Kalle Valo