From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D283C001E0 for ; Tue, 15 Aug 2023 20:01:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240089AbjHOUBP (ORCPT ); Tue, 15 Aug 2023 16:01:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240152AbjHOUBE (ORCPT ); Tue, 15 Aug 2023 16:01:04 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3FB4883; Tue, 15 Aug 2023 13:01:04 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C8C5065F37; Tue, 15 Aug 2023 20:01:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9524AC433C7; Tue, 15 Aug 2023 20:01:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1692129663; bh=EvZs3//r+5RX7/NTYdrqg9AZrjkjRWoh42oY8jUURpQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hLFxBTyfGv+cv3LAjiUVd/ceDyr3FGOOd5FZYJq3ZCZ9s3lHDhyMffM2pAVCDJuL9 jv65lKr46zV1ZWCOlZ1uFLoV1Houz3nAEDAec0HKgA3dz7W4hYD62ThfF5TkqH5jQM 4IvX11YnlpPsQbv9ahey9MFs7pEkQ305Y5GMYHuoiNgvJRIfc/wAVF4uPFytmhub0s X8s5+lWSuosZRzK2JRFOS+FKfA+oKhws7iKsfB98bJw9/ycxt8yVzmNs7hYczaXqXG Q6HOF88QDzICvaQfc99CrC9yUJDffOrXl0SEDQOm97s5t+XtJuIBAj4OG66IEunLw6 2v8IQ7axsh0Tg== Date: Tue, 15 Aug 2023 22:00:55 +0200 From: Wolfram Sang To: =?utf-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= Cc: Rob Herring , Svyatoslav Ryhel , Andi Shyti , Krzysztof Kozlowski , Conor Dooley , linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 1/2] dt-bindings: i2c: add binding for i2c-hotplug-gpio Message-ID: Mail-Followup-To: Wolfram Sang , =?utf-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= , Rob Herring , Svyatoslav Ryhel , Andi Shyti , Krzysztof Kozlowski , Conor Dooley , linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20230729160857.6332-1-clamor95@gmail.com> <20230729160857.6332-2-clamor95@gmail.com> <20230811173752.GA3639776-robh@kernel.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="VNSvbZBwBusE8ygy" Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org --VNSvbZBwBusE8ygy Content-Type: text/plain; charset=us-ascii Content-Disposition: inline > Not a driver but a group of devices (possibly discovered dynamically) > behind a passive gate (like e.g. PCA9517A with EN tied to a connector pin). > It's not much different to a I2C gate or mux with a single child bus > (i2c-mux-gpio that has only a single child). I agree. To prevent the the bus from spikes when connecting / disconnecting something like PCA9517A should be in place. And this one can be considered a 1:1 mux. Just with the exception that Linux cannot control the gate, but can only react to changes to the enable pin. Can't we have a driver for the PCA9517 which gets interrupts when the enable pin changes and then adds / removes the child i2c adapter? --VNSvbZBwBusE8ygy Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmTb2XIACgkQFA3kzBSg KbZ0CQ/9HaWnOT59/L9KdKzqxf5OJrVvdhwELVc04Bnuu0DQf3l2oH2msar6ptKP mLZgg2zD8LDypWOGe34YlKy1UvUcis8bYwpYSg8yOXg6XZWd+iyJkgm5SsutkH2j Jufawu1SRM06hgPC1UGtnIR17aNra2bRI/N7XgptIvfiWriNx/8klVPmXMfvkcjt cYHsJ8d6vRls9nOEYXruiTMYJ5TGlj9qaq4Kw3sYg/nGsIoreVkRHjQJfQY7tnkm vpRaQKL3MPurpBDaW/Ov0KaElminXzumRX0qDqP4qOmPnnCJIZftIAQs5NhU/3xj 15ZGKz9KrWv7f8RDaaC6pO81hUyNOgC6c0/dWC+Nl2CTlmsLoZqohYex0hRx5o4U DSg8jmF2MAofXISjuTwzjhssS113W790W9vEqncuu0AavfW+sAkJjU05iwvyAGsI fWNOdKmb1vJ/+nMpXoR0xGIxGqhnZkDO3/oOOEg25ORrYsDWjSO7mflNkcVtTgTL Rz6nsSFWHad+0JAHbWbdBCFRWX4zQtCQX1yKbp6Hs/sWh95JSlKE3fp3QkBm1TKZ 3Vj7tpc3j7dgVUeTkxwYr6HJvmWInxLSrsEfsDTbBg7h789GL9pycF37VnKB9GuC rFhFicZnd3A549q/oDygX7yYE8OXhQdUG7xmjN53U0pD7QuVjQ8= =YOUx -----END PGP SIGNATURE----- --VNSvbZBwBusE8ygy--