Re: [PATCH 01/13] wifi: cfg80211: Add provision to advertise multiple radio in one wiphy

Johannes Berg
2024-04-10T07:56:41Z

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:
> > > >
> > > > > + * @hw_chans: list of the channels supported by every constituent underlying
> > > > > + * hardware. Drivers abstracting multiple discrete hardware (radio) under
> > > > > + * one wiphy can advertise the list of channels supported by each physical
> > > > > + * hardware in this list. Underlying hardware specific channel list can be
> > > > > + * used while describing interface combination for each of them.
> > > >
> > > > I'd expect there to be a limit on channels being within a single band on
> > > > a single "hardware"?
> > > >
> > >
> > > There are ath12k hardware supporting multiple band which need to be
> > > registered under one mac80211_hw/wiphy. This design is to support such
> > > hardware.
> >
> > Oh OK, that was something that I didn't have in mind any more, or never
> > knew or paid attention to.
>
> Would it work to leave the phy reporting pretty much as it is now, but add
> a 'associated_peer_radios' list section, so that each phy could report the phys
> associated with it? Then user-space, driver, mac80211 etc could look up the
> other phys as needed to get a full picture?
>

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