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Subject: Re: [PATCH 1/9] wifi: mac80211: allow enabling chanctx until hw
 registration
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Sean Wang <sean.wang@kernel.org>
Cc:     Sean Wang =?UTF-8?Q?=28=E7=8E=8B=E5=BF=97=E4=BA=98=29?= 
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Date:   Fri, 19 Aug 2022 19:36:25 +0200
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On Fri, 2022-08-19 at 19:16 +0200, Johannes Berg wrote:
> Hi Sean,
>=20
> > > If we really, really need to allow changing the ops, then we should
> > > probably make a much larger change to not even pass the ops until
> > > register, though I'm not really sure it's worth it just to have mt792=
1
> > > avoid loading the firmware from disk before allocation?
>=20
> > Thanks for your input. I thought I'd try to write a patch to follow up
> > on the idea you mentioned here.
> >=20
>=20
> I think you will introduce a bug into mt7921 when you do this, and I'm
> curious if you will find it ;-)
>=20

Actually, no, clearing WIPHY_FLAG_IBSS_RSN in mt7921_init_wiphy()
actually does nothing, I thought it was required.

Anyway, the point is that now we set some defaults in alloc_hw(), some
based on the ops, and then the driver could override those before it
does register_hw().

With the proposed change, that's no longer possible, and I'm not sure I
(or you) would want to audit each and every driver - WIPHY_FLAG_IBSS_RSN
was something that showed up easily in grep though.

So I still think you're better off doing it in the firmware file :-)

johannes