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

[icenowy]

å 2017-10-05 14:58ïKalle Valo åéï
> Icenowy Zheng <icenowy@xxxxxxx> writes:
>
> > ä 2017å10æ4æ GMT+08:00 äå6:11:45, Maxime Ripard
> > <maxime.ripard@xxxxxxxxxxxxxxxxxx> åå:
> > > On Wed, Oct 04, 2017 at 10:02:48AM +0000, Arend van Spriel wrote:
> > > > On 10/4/2017 11:03 AM, Icenowy Zheng wrote:
> > > > >
> > > > >
> > > > > ä 2017å10æ4æ GMT+08:00 äå5:02:17, Kalle Valo <kvalo@xxxxxxxxxxxxxx>
> > > åå:
> > > > > > Icenowy Zheng <icenowy@xxxxxxx> writes:
> > > > > >
> > > > > > > Allwinner XR819 is a SDIO Wi-Fi chip, which has the
> > > functionality to
> > > > > > use
> > > > > > > an out-of-band interrupt pin instead of SDIO in-band interrupt.
> > > > > > >
> > > > > > > Add the device tree binding of this chip, in order to make it
> > > > > > possible
> > > > > > > to add this interrupt pin to device trees.
> > > > > > >
> > > > > > > Signed-off-by: Icenowy Zheng <icenowy@xxxxxxx>
> > > > > > > Acked-by: Rob Herring <robh@xxxxxxxxxx>
> > > > > > > ---
> > > > > > > Changes in v3:
> > > > > > > - Renames the node name.
> > > > > > > - Adds ACK from Rob.
> > > > > > > Changes in v2:
> > > > > > > - Removed status property in example.
> > > > > > > - Added required property reg.
> > > > > > >
> > > > > > >   .../bindings/net/wireless/allwinner,xr819.txt      | 38
> > > > > > ++++++++++++++++++++++
> > > > > > >   1 file changed, 38 insertions(+)
> > > > > > >   create mode 100644
> > > > > >
> > > Documentation/devicetree/bindings/net/wireless/allwinner,xr819.txt
> > > > > >
> > > > > > 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?