From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sipsolutions.net (s3.sipsolutions.net [168.119.38.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D3BA0305696 for ; Thu, 4 Jun 2026 11:02:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=168.119.38.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780570951; cv=none; b=j6qHSoOkwUbVLnAKu7f32fR2MhdcKBXa+40uFuZZQs2Ry5/DrOL3oyU9B9y/YkPffsaKcOJojhhO9WLgdJI4bej70B+HqxmKYAgdccx8hdhaDrMkjTIU2NclYLoNdx9OR5JAEGgP4YO2lKjW/9Tp7eXDyNBhjc9vW3redMmgZlE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780570951; c=relaxed/simple; bh=C+RfC3kcC5jGSP2ehVJ/y1oBokVSArcpGVZD6oI1LIg=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=eXKd9mI5oXBRpKPi9Qokrdp/NFY+qlCYvlruPioM0gokJg34rLFVm4d+qqNCvtJ+9ZYTRfbvMkoO32ZCegtuEGm3AREEk7qRz5cjB82HhWcHmmuxNyoJUcp85St2d0W25OBnlN9Z0fzRBkcXRUZ6cgzpBxVgBj+RMIy7V4Xkucs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=permerror header.from=sipsolutions.net; spf=none smtp.mailfrom=sipsolutions.net; dkim=pass (2048-bit key) header.d=sipsolutions.net header.i=@sipsolutions.net header.b=juoCsuBv; arc=none smtp.client-ip=168.119.38.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=permerror header.from=sipsolutions.net Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=sipsolutions.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=sipsolutions.net header.i=@sipsolutions.net header.b="juoCsuBv" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=MIME-Version:Content-Transfer-Encoding: Content-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=QoUl+iy4Q0l0d3iPZTSd3uGPnK7pDKJYC3R3dIC27+w=; t=1780570949; x=1781780549; b=juoCsuBvoLZQQvS+q/FbpKC2/A6w3UVbIJVALcjXr3QEHwM kjVdinIjib4OJLhlFXGGkdSL3WKkVbfQTk+ysrxH+gzebkM87a4o0uUGM4Jm8tNwlntAgyRUVp3+d Crs0c25h7b9KfQmqRhzViVZBktww8Iki/i1whwgWKu76LzSJoirIxdeb3rleJQ9zV3tNOGUwoAiz1 qIB6+ZwRC6lXjlZH0Qt9tohPM9Ms23HHqim1eV+XMjvXJHutc8XRQRN5MEUj090os9FYwgQ+rhITu tsMtZGjIqKgw0LIq7VhwGSbgo6/AGFojEwXVqX18YgyPnWOHe+7cTv0PkzVd7c8g==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.98.2) (envelope-from ) id 1wV5qD-00000000Rhy-3iHH; Thu, 04 Jun 2026 13:02:26 +0200 Message-ID: <09e2bd29cf9f8ad3fe64776343fd1e06426ea362.camel@sipsolutions.net> Subject: Re: [PATCH wireless-next 1/2] wifi: nl80211: Add NL80211_ATTR_MAX_CH_SWITCH_TIME attribute From: Johannes Berg To: Shashikala Prabhu Cc: linux-wireless@vger.kernel.org, vikram@qti.qualcomm.com, kiranv@qti.qualcomm.com, pshashik@qti.qualcomm.com, cgopi@qti.qualcomm.com, ybasamma@qti.qualcomm.com, vthiagar@qti.qualcomm.com, sivad@qti.qualcomm.com, uvignesh@qti.qualcomm.com, mohathan@qti.qualcomm.com, abishekg@qti.qualcomm.com Date: Thu, 04 Jun 2026 13:02:25 +0200 In-Reply-To: <20260518103106.1462604-2-shashikala.prabhu@oss.qualcomm.com> References: <20260518103106.1462604-1-shashikala.prabhu@oss.qualcomm.com> <20260518103106.1462604-2-shashikala.prabhu@oss.qualcomm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-malware-bazaar: not-scanned On Mon, 2026-05-18 at 16:01 +0530, Shashikala Prabhu wrote: > From: Chandru Gopi >=20 > IEEE Std 802.11-2024 subclause 9.4.2.216 (Max Channel Switch Time element= ) > defines a Switch Time field in the Channel Switch Announcement (CSA) > element that indicates the time delta between the time the last beacon > is transmitted by the AP in the current channel and the expected time > of the first beacon transmitted by the AP in the new channel. >=20 > Add a new u32 nl80211 attribute, NL80211_ATTR_MAX_CH_SWITCH_TIME, > to carry this value in the NL80211_CMD_CH_SWITCH_STARTED_NOTIFY > event. Userspace can use this information to decide whether to > remain connected or disconnect before the AP moves to the new > channel. This really confused me a lot because that event is used on both sides ... don't include the new netlink attribute when it's on the AP side. Also bad split with the patches - make one cfg/nl80211 API patch, and one mac80211 patch. > NL80211_ATTR_NPCA_PUNCT_BITMAP, > =20 > + NL80211_ATTR_MAX_CH_SWITCH_TIME, > /* add attributes here, update the policy in nl80211.c */ nit: looks odd without the blank line > +++ b/net/wireless/nl80211.c > @@ -1093,6 +1093,7 @@ static const struct nla_policy nl80211_policy[NUM_N= L80211_ATTR] =3D { > [NL80211_ATTR_NPCA_PRIMARY_FREQ] =3D { .type =3D NLA_U32 }, > [NL80211_ATTR_NPCA_PUNCT_BITMAP] =3D > NLA_POLICY_FULL_RANGE(NLA_U32, &nl80211_punct_bitmap_range), > + [NL80211_ATTR_MAX_CH_SWITCH_TIME] =3D { .type =3D NLA_U32 }, That seems wrong since it's output only, it shouldn't even be accepted on input. johannes