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 D2AA7C5479D for ; Mon, 9 Jan 2023 19:19:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237626AbjAITT0 (ORCPT ); Mon, 9 Jan 2023 14:19:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234934AbjAITTX (ORCPT ); Mon, 9 Jan 2023 14:19:23 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 40486111C; Mon, 9 Jan 2023 11:19:22 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CD5D2610AA; Mon, 9 Jan 2023 19:19:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E782C433EF; Mon, 9 Jan 2023 19:19:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1673291961; bh=I9vhhoMs3WFpRtM3ZAfcVlbwKo9qXFT3gHzyMFQGbpM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ik95PrWuMaaoqHh+hzhd4DXDCynr1Zbrf7mpaj0QRYp41ZN8NwgXUXGaUKREWpIu3 jXZn4EZwon9Xao8ZDYi0Brum/mHx0x169//r3s186LRW8fT+ydJmr7gNDvenSISijc AS/I9BRmf+2zNHoDNbZfdta5E1+CJ0m7RcVVedYux1HUmiF8Vp8Bwud6OB5rvpsiDL dgMe5kzoRfMQEftgW+PIC+h6OkQMS1Qjm306yInoz1973ls2ZyjCzun4qYHpuilQlm gSI8sS2J9oIPxZd6+dbYCHkRTlDjYUXZyoM1lFy1f0VT14T7rRZmSCri/fuAGq45iB N3SGWLrcRUG5g== Date: Mon, 9 Jan 2023 19:19:14 +0000 From: Mark Brown To: William Zhang Cc: Rob Herring , Linux SPI List , Broadcom Kernel List , anand.gore@broadcom.com, tomer.yacoby@broadcom.com, dan.beygelman@broadcom.com, joel.peshkin@broadcom.com, f.fainelli@gmail.com, jonas.gorski@gmail.com, kursad.oney@broadcom.com, dregan@mail.com, Krzysztof Kozlowski , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 03/16] dt-bindings: spi: Add spi peripheral specific property Message-ID: References: <20230106200809.330769-1-william.zhang@broadcom.com> <20230106200809.330769-4-william.zhang@broadcom.com> <3ff9a7fa-25dd-701c-078e-03e47bd3c08b@broadcom.com> <6720e3a4-dbbb-f490-98db-511a52b9a2ab@broadcom.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="lmcZn8x/tmKJQ3ye" Content-Disposition: inline In-Reply-To: <6720e3a4-dbbb-f490-98db-511a52b9a2ab@broadcom.com> X-Cookie: Editing is a rewording activity. Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --lmcZn8x/tmKJQ3ye Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Jan 09, 2023 at 12:06:13AM -0800, William Zhang wrote: > > On Fri, Jan 6, 2023 at 9:27 PM William Zhang wrote: > > Keeping the clock on or not would affect all devices unless you have a > > per device clock you can gate, so making this a per device flag > > doesn't make sense. > This applies only to each chip select. There is only one device under each > chip select. So won't impact any other devices under other cs. I don't understand how this would work - usually a SPI controller has a single set of clock, MOSI and MISO lines with the only per device thing being the chip select. If the clock line is used by all devices then it must be kept on for all of them if it's to be kept on for one of them. --lmcZn8x/tmKJQ3ye Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmO8aLIACgkQJNaLcl1U h9DqAQf8CYCqNr+Diaohf358fnuLfnlMbJCW8n2slDDq0RjrhBRy8QpuXKsw6ug1 hd7C56/d+UUDBgj0PtsQEcSRl1092xgblNfUTQPAeEltcRogkKwOuLxtP6Z0dlka T4mDP8iJOmREbLaN2P6oyS6DlXfnnEUMm0bjgeUCdqOLF0dBgNtcAkDTb7VH8nPO ZRUBnlcihawhrHZKfiwIYyhWqel4XylYCok+JURDvqVvTVbHQpC0epNk/zJJH3fg zQyZykohWUty87j+sTmYkhsLWiPZAC0nUlCJaoae4GDw7mc3V0gZNxP/zS6XqR4K qcs6uYpSzKkCGloysSZMs6UrfaZE/Q== =x6ap -----END PGP SIGNATURE----- --lmcZn8x/tmKJQ3ye--