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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0DBEEC433E0 for ; Mon, 29 Mar 2021 17:04:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C34A461959 for ; Mon, 29 Mar 2021 17:04:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231250AbhC2REO (ORCPT ); Mon, 29 Mar 2021 13:04:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50816 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229822AbhC2REB (ORCPT ); Mon, 29 Mar 2021 13:04:01 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 81F58C061574 for ; Mon, 29 Mar 2021 10:04:01 -0700 (PDT) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lQvJ0-0006TN-0S; Mon, 29 Mar 2021 19:03:58 +0200 Received: from ukl by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1lQvIz-0006VR-NZ; Mon, 29 Mar 2021 19:03:57 +0200 Date: Mon, 29 Mar 2021 19:03:57 +0200 From: Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= To: Clemens Gruber Cc: linux-pwm@vger.kernel.org, Thierry Reding , Sven Van Asbroeck , linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 4/7] pwm: pca9685: Support staggered output ON times Message-ID: <20210329170357.par7c3izvtmtovlj@pengutronix.de> References: <20210329125707.182732-1-clemens.gruber@pqgruber.com> <20210329125707.182732-4-clemens.gruber@pqgruber.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="ilk36xqvfaxvav3n" Content-Disposition: inline In-Reply-To: <20210329125707.182732-4-clemens.gruber@pqgruber.com> X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ukl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --ilk36xqvfaxvav3n Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Mar 29, 2021 at 02:57:04PM +0200, Clemens Gruber wrote: > The PCA9685 supports staggered LED output ON times to minimize current > surges and reduce EMI. > When this new option is enabled, the ON times of each channel are > delayed by channel number x counter range / 16, which avoids asserting > all enabled outputs at the same counter value while still maintaining > the configured duty cycle of each output. >=20 > Signed-off-by: Clemens Gruber Is there a reason to not want this staggered output? If it never hurts I suggest to always stagger and drop the dt property. Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | https://www.pengutronix.de/ | --ilk36xqvfaxvav3n Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEfnIqFpAYrP8+dKQLwfwUeK3K7AkFAmBiCHoACgkQwfwUeK3K 7AnRIQf/W5F4T5BkG5hwd2fJ5VZkg6UaAlvJQfjxLY83XqP3GfgxSNGGb5Wr6kZt SciiIuQggfvOY7hIMJS9p8NcCRyMg39GSlYIuabQn/QjPOL22cfXsBe1w+oSTOxy PbxbcM842qyGRXGHGQD/OTXK9rpFwsZdOTg3LlSAPh+oyXLbPYk/UImV7Pu+8Oe9 ViFMITfK0z0Gm2elPu5P4tAWfvQKdN5zCWsaF4TwG9LdjjTzsErhm1sg2bLdzIS5 3mrquF1ApuV3GnxywZrrq6WL6u9gZonLjSeFIzh1zrj9iFsA/Lr4OlHa1nF0e8aB Sg+AcjNDbh/9iY/7flzedDV+v/TUuw== =H/BD -----END PGP SIGNATURE----- --ilk36xqvfaxvav3n--