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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 80D97C433EF for ; Fri, 18 Feb 2022 09:17:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:References:Cc:To:Subject:From: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=RWMMk4KBokauEn65OKRBYrWRC4w7ksCjKXLjALQxc2o=; b=IEWwBTdfC2aHLD XR7+nKQI58lDNQ5kaQmixP9mnz6IhVhi4rWLWEF/Niu598udCBK/w1laRnsBXz3JG8nUc9iwXs5rK G/smrlPGTQq5It6UeIRp+PtOemWVgtjhYqMMYrDA+iHcikYU0xFZZ6kp/AZvr03UxJkj8r+8644v4 gHG6WRnwRu4gbZUvuVLQzVqZ1RqIa9MquaNaoDtoNZqJck/f8DDOHpGRfWMGnPpmP8J1nmYxKnvoJ YfcyYOYzU/t/WoQaBJCJo0EbTpZRRDL8XtQqQxcfuOWbojet3Bld6ZtsmT5J43mifPqOOPvU+Ze3z h30gZ0iDcBK9Wu8fiRAg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nKzNA-00DQbu-J1; Fri, 18 Feb 2022 09:16:16 +0000 Received: from cpanel.siel.si ([46.19.9.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nKzN6-00DQb3-0V for linux-arm-kernel@lists.infradead.org; Fri, 18 Feb 2022 09:16:14 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=norik.com; s=default; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:References:Cc :To:Subject:From:MIME-Version:Date:Message-ID:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=bE833ii6JBmVkFFXcZO7xdCOK5mk+A6Va/gURh5A52Q=; b=eUp0OXuV8NHIN2mwM2Ta8znO1S 2PTSsHILY65SAMrFQVhDhur2u379KzvB+OihOB7rqv70dAJjoq0p85MxACwc68yZfYTPSOA2dKXex 1xIBYYHtWEbUytn/u5gnv16B9McXIMdgydKYvYD4fBhyDAz/qxotrK/2ak5Nx2x4di5PD+BeaqDAQ zesfyI8Mpb5SqBe1Fs9WRexYP+x1L457parH+5sCuOXTmEq1wvGMH5IFs0E4e1dM0/XqddoMokOXp q/hnf7IDWC3ofPJJ4q+Xj4+yLOy8FxpsxWdTunlzwAKw293TZ+d+//zBgeF9Dv7dqx30AkYRfbHb4 gyuAiXFw==; Received: from 89-212-21-243.static.t-2.net ([89.212.21.243]:33112 helo=[192.168.69.86]) by cpanel.siel.si with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94.2) (envelope-from ) id 1nKzMp-006Wuz-UL; Fri, 18 Feb 2022 10:16:03 +0100 Message-ID: Date: Fri, 18 Feb 2022 10:16:05 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 From: Andrej Picej Subject: Re: [PATCH RESEND 3/4] ARM: dts: imx6ul: phycore: Change USB LDO voltage for usb compliance To: Shawn Guo 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 References: <20220131080526.1171072-1-andrej.picej@norik.com> <20220131080526.1171072-4-andrej.picej@norik.com> <20220212054627.GZ4909@dragon> Content-Language: en-GB In-Reply-To: <20220212054627.GZ4909@dragon> X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cpanel.siel.si X-AntiAbuse: Original Domain - lists.infradead.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - norik.com X-Get-Message-Sender-Via: cpanel.siel.si: authenticated_id: andrej.picej@norik.com X-Authenticated-Sender: cpanel.siel.si: andrej.picej@norik.com X-Source: X-Source-Args: X-Source-Dir: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220218_011612_440286_8F1B652F X-CRM114-Status: GOOD ( 16.17 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 12. 02. 22 06:46, Shawn Guo wrote: > 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? Sorry for late response, but I had to look into this a bit to see the reason for using always-on. The consumer should turn the regulator on/off, but the consumer doesn't do that. If regulator is not specified as always-on the regulator stays in disabled state, even when usb device is used. That's why this was added here. This should probably be fixed on consumer side. If you want I can drop the patch from this series and submit the fixed version when the stuff gets resolved. BR, Andrej _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel