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Message-ID: <31f30c0e318904f3a082c7f213576ceb1f407141.camel@sipsolutions.net>
Subject: Re: [PATCH 01/13] wifi: cfg80211: Add provision to advertise
 multiple radio in one wiphy
From: Johannes Berg <johannes@sipsolutions.net>
To: Ben Greear <greearb@candelatech.com>, Vasanthakumar Thiagarajan
 <quic_vthiagar@quicinc.com>, Karthikeyan Periyasamy
 <quic_periyasa@quicinc.com>,  ath12k@lists.infradead.org
Cc: linux-wireless@vger.kernel.org
Date: Wed, 10 Apr 2024 09:56:33 +0200
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On Fri, 2024-03-29 at 07:47 -0700, Ben Greear wrote:
> On 3/29/24 07:30, Johannes Berg wrote:
> > On Fri, 2024-03-29 at 19:41 +0530, Vasanthakumar Thiagarajan wrote:
> > > >=20
> > > > > + * @hw_chans: list of the channels supported by every constituen=
t underlying
> > > > > + *	hardware. Drivers abstracting multiple discrete hardware (rad=
io) under
> > > > > + *	one wiphy can advertise the list of channels supported by eac=
h physical
> > > > > + *	hardware in this list. Underlying hardware specific channel l=
ist can be
> > > > > + *	used while describing interface combination for each of them.
> > > >=20
> > > > I'd expect there to be a limit on channels being within a single ba=
nd on
> > > > a single "hardware"?
> > > >=20
> > >=20
> > > There are ath12k hardware supporting multiple band which need to be
> > > registered under one mac80211_hw/wiphy. This design is to support suc=
h
> > > hardware.
> >=20
> > Oh OK, that was something that I didn't have in mind any more, or never
> > knew or paid attention to.
>=20
> Would it work to leave the phy reporting pretty much as it is now, but ad=
d
> a 'associated_peer_radios' list section, so that each phy could report th=
e phys
> associated with it?  Then user-space, driver, mac80211 etc could look up =
the
> other phys as needed to get a full picture?
>=20

There's not really a good way to _do_ that short of creating multiple
wiphys, but that causes _massive_ complexity in the stack (both cfg80211
and mac80211) so we rejected it years ago.

johannes