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 5B727C433F5 for ; Sat, 12 Feb 2022 05:46:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231708AbiBLFqk (ORCPT ); Sat, 12 Feb 2022 00:46:40 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:55790 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231688AbiBLFqg (ORCPT ); Sat, 12 Feb 2022 00:46:36 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8AF5B28E3E for ; Fri, 11 Feb 2022 21:46:34 -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 C014F608D5 for ; Sat, 12 Feb 2022 05:46:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0CD39C340ED; Sat, 12 Feb 2022 05:46:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1644644793; bh=D8Z7s01IRXNMSKDuM2y3UXpuZ9sPd9PVWLyQABy4pE4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LfdSAuG7i8zkiDFXomC+6PKzqNDPkVibzZzI6+8ERXRPGJbSVM88H7bTRGR0xssip sLDrYieXdZbg/RYLkm63X/eXkpjGWe/xgtHQR2QpEZbBkvZxmQslvqNJt/qCBeX0AM nCFTx6hAqYqJ0lVQqbbDWUjpBoLf/hNbsMyQEnRtU9tPtZtmIDI14Uu5XbYhsgqeOv QWVS/fZSTE2XwLCxZ8Vu7Arqee3dJTS43efVg3sAjvX/7Y0MzMhICI6RnXyxaK7nQL vPahL74BI0z3KsDv4MpgBqwBXugSopbp/SbiakgUkGRYDFyNrrk9eNR1QNdzfVLfxa Rn9/IZwY2QwIQ== Date: Sat, 12 Feb 2022 13:46:27 +0800 From: Shawn Guo To: Andrej Picej Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, robh+dt@kernel.org, kernel@pengutronix.de, leoyang.li@nxp.com, krzysztof.kozlowski@canonical.com, festevam@gmail.com, linux@rempel-privat.de, arnd@arndb.de, linux-imx@nxp.com, y.bas@phytec.de Subject: Re: [PATCH RESEND 3/4] ARM: dts: imx6ul: phycore: Change USB LDO voltage for usb compliance Message-ID: <20220212054627.GZ4909@dragon> References: <20220131080526.1171072-1-andrej.picej@norik.com> <20220131080526.1171072-4-andrej.picej@norik.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220131080526.1171072-4-andrej.picej@norik.com> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Mon, Jan 31, 2022 at 09:05:25AM +0100, Andrej Picej wrote: > From: Yunus Bas > > According to the NXP usb compliance reference, the USB data lines for > Full/Low speed are connected to the ARM USB LDO, which is set to > minimum-voltage = 2.6V and maximum-voltage = 3.4 V. When the regulator > is deactivated, the data lines are defaulty driven with 2.6V, which is > not USB Full-Speed compliant. To be compliant, we need to activate the > USB LDO regulator and set it to the value of 3V, which is the specified > value in the USB specification. > > Signed-off-by: Yunus Bas > Signed-off-by: Andrej Picej > --- > arch/arm/boot/dts/imx6ul-phytec-phycore-som.dtsi | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/arch/arm/boot/dts/imx6ul-phytec-phycore-som.dtsi b/arch/arm/boot/dts/imx6ul-phytec-phycore-som.dtsi > index 3cddc68917a0..2e03be3d43ec 100644 > --- a/arch/arm/boot/dts/imx6ul-phytec-phycore-som.dtsi > +++ b/arch/arm/boot/dts/imx6ul-phytec-phycore-som.dtsi > @@ -83,6 +83,11 @@ eeprom@52 { > }; > }; > > +®_3p0 { > + regulator-min-microvolt = <3000000>; > + regulator-always-on; Rather than setting it always-on, shouldn't the consumer of the regulator turn it on/off as needed? Shawn > +}; > + > &snvs_poweroff { > status = "okay"; > }; > -- > 2.25.1 >