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Message-ID: <cc9b25a584471699375d85f12e24a26098397ad5.camel@sipsolutions.net>
Subject: Re: [PATCH] wifi: mt76: inititalize sband.band to correct value
From: Johannes Berg <johannes@sipsolutions.net>
To: Bert Karwatzki <spasswolf@web.de>, Lorenzo Bianconi
 <lorenzo@kernel.org>,  Felix Fietkau <nbd@nbd.name>, Ryder Lee
 <ryder.lee@mediatek.com>
Cc: linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org
Date: Wed, 07 Feb 2024 11:52:07 +0100
In-Reply-To: <20240207072253.4189-1-spasswolf@web.de>
References: <20240207072253.4189-1-spasswolf@web.de>
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On Wed, 2024-02-07 at 08:22 +0100, Bert Karwatzki wrote:
> Set phy->sband_{2,5,6}g.sband.band to the correct enum value, otherwise
> the ieee80211_register_hw() will fail to register the device.

So turns out that technically, it wasn't needed before because cfg80211
*will* set sband->band, but *mac80211* now requires it to have been set
before ...

We could do a trivial fix in mac80211 as well:

--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -1124,7 +1124,7 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
 			supp_he =3D supp_he || iftd->he_cap.has_he;
 			supp_eht =3D supp_eht || iftd->eht_cap.has_eht;
=20
-			if (sband->band =3D=3D NL80211_BAND_2GHZ)
+			if (band =3D=3D NL80211_BAND_2GHZ)
 				he_40_mhz_cap =3D
 					IEEE80211_HE_PHY_CAP0_CHANNEL_WIDTH_SET_40MHZ_IN_2G;
 			else


but seems like no other driver even likely needed this, and it's
probably less reliable in the long term?

Or do both?

johannes