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

From: icenowy
Date: Sat Oct 07 2017 - 09:02:05 EST


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?

By doing some tests, XR819 is in the the CW1x60 family, which is not
yet well supported by cw1200 driver.

More work should be needed for support xr819 in cw1200 driver.