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Message-ID: <d13570223dd4bad257a719fb77b0cc4f2839cb36.camel@sipsolutions.net>
Subject: Re: [PATCH v2,2/2] wifi: mac80211: Refactor STA CSA parsing flow
From: Johannes Berg <johannes@sipsolutions.net>
To: Michael-cy Lee =?UTF-8?Q?=28=E6=9D=8E=E5=B3=BB=E5=AE=87=29?=
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Cc: "linux-mediatek@lists.infradead.org"
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 Evelyn Tsai =?UTF-8?Q?=28=E8=94=A1=E7=8F=8A=E9=88=BA=29?=
 <Evelyn.Tsai@mediatek.com>, "lorenzo@kernel.org" <lorenzo@kernel.org>,
 Money Wang =?UTF-8?Q?=28=E7=8E=8B=E4=BF=A1=E5=AE=89=29?=
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Date: Mon, 27 Nov 2023 11:02:25 +0100
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References: <20231113021107.13110-1-michael-cy.lee@mediatek.com>
	 <20231113021107.13110-2-michael-cy.lee@mediatek.com>
	 <9dd37c008572bb0938bd0d0a0fa207dd70aa8b98.camel@sipsolutions.net>
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Hi,

> The old flow also converted the Element to operation elements first,
> then it used ieee80211_chandef_vht_oper() to build the new chandef from
> operation elements.
>=20
> We think it's necessary for the case that AP is trying to switch to a
> 160 MHz bandwidth, while the STA doesn't support the 160 MHz bandwidth.

Yeah, you're right, it did before and I suppose it's still easier than
managing two conversions, since some formats are the same.

> Just like what had been done during the association,
> ieee80211_chandef_vht_oper() checks the STA's capabilities and builds a
> valid chandef for the STA. However, even if the STA doesn't support the
> 160 MHz bandwidth, ieee80211_chandef_vht_oper() doesn't mark the
> conn_flags as IEEE80211_CONN_DISABLE_160MHZ, so the same check is
> necessary when handling CSA.

Right.

> Like we had discussed in previous mail, we expected the patch will be
> simplified.

Yeah I just circled back to it for stupid reasons (I guess mostly forgot
to mark in patchwork that you were going to make changes) and looked
again after having looked at all the other code in the series I posted
late last week.

> In summary, the steps for STA to handling CSA are,=20
> 1. parse the new channel information from either operating class or
> WBCS Element.
> 2. convert the channel information into corresponding operation Element
> (HT/VHT in 5 GHz band and HE/EHT in 6 GHz band)
> 3. Build a valid chandef from the operation Element.
>=20

Sounds good.

johannes