From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=178.238.236.174 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792999883; b=wlhQMx9Ml4BDJQ16MZD5F99KpGAgEIgLZJFZT0qrp2OrYLEgeVlaOG1aBizy1Jai8b07 Ov3jn6IRRtyOAEer5Xg3HsEWFRABLkOb0BulpqisCWpUWMyp+P8h+ORVVujawXby//JRP gvv2oaKh5b8BZ2NOAXRG7eskgWOLb3C7MOJfW6ZJcaJItn7Ed9WxLmDtSCn+DaR30tJtv UUqu48QkLMtYEH4sX5wojXquepLHj3iOkQS1rQZd7mcyNPP3IzzHteWuuQhCl6ryg55kz gUp2Po4pwB18fZz6QBdVPE1MSXBv2GbBzUDzWGeI6nhNPRKMjlTKDjuznPD8ZONaAAQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792999883; h=DMARC-Filter:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: In-Reply-To:References:X-Mailer:MIME-Version:Content-Type: Content-Transfer-Encoding; bh=3k2gQfSx3BsVVF9yxHoO/WKzvaeGtbZNRBYzH/o7M2o=; b=Ve0IQy1Qz0IusfT8VZgBmiQRjuE9KHRM7QVvOBnG4zKf3xPDNJCNlm3zy1LFL5+wUVmM ETsxAKtEU16zTEER1mpT9/8g02z3F6UTJJ9WM5T8kL2fYSAC19PKSnZNpFySH1PYhZA8d O9EiiOgJbgBLBObajSwdB68XQv5ez5roGe2GQYdNMuRFjoTz/QWCrLdC28QgO8iGH8tRM ssC5af5DDr4EsxmX2rO7Qbo9u7WNUIUOsCnUgk89nDFFk0nULwEBESPkL6F/OkR5W86sl Ts6APEoVZ+OFjBgAg85tUIuMEAb2FMocobKu8B6gyQTzxfiOpy5cmxj4w2g6MXRhLJQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=kemnade.info; spf=pass smtp.mailfrom=kemnade.info; dkim=pass header.d=kemnade.info header.i=@kemnade.info header.a=rsa-sha256 header.s=20220719 header.b=xPftORw7; arc=none smtp.remote-ip=178.238.236.174 Received: from mail.andi.de1.cc (mail.andi.de1.cc [178.238.236.174]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8A211606A31B; Mon, 26 Oct 2026 07:31:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 8A211606A31B Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=kemnade.info Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kemnade.info Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kemnade.info header.i=@kemnade.info header.a=rsa-sha256 header.s=20220719 header.b=xPftORw7 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=kemnade.info; s=20220719; h=References:In-Reply-To:Subject:Cc:To:From: Reply-To:Content-ID:Content-Description; bh=3k2gQfSx3BsVVF9yxHoO/WKzvaeGtbZNRBYzH/o7M2o=; t=1792999883; x=1794209483; b=xPftORw7Wf57gPlwZKEQbrEdkbnBHATENc0ed3687dBlnRGCANqLnqTvwoIlqjrswgYm2B/UwV6 a0f/SyX+CdlaEvLb7WAtAh6V8LYrcPpsXiaiL+di7zgkB3447Y2NGp5hkq44dXDXX+Jm9GD0YnG/z JqQDRPUAajp/uQ4JS1TIGLtYIUcaSul6G2TFrlds2TFpFXijJhOHHfeR6O14RPnWOXzjzv22IfEr8 Vc720/CwOjRoNW9UlUErutu9XBPRH/MZezrrB124x5OEo1MV/LRk5/cd/uNIaeL76Y4KiNAc3vl/o +F9R9/st08nzpfitD7wBXHNv5VWx7Jd+DMbg==; Date: Mon, 26 Oct 2026 08:30:58 +0100 From: Andreas Kemnade To: Pablo Mazzini Cc: Frank Li , Sascha Hauer , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Alistair Francis , Pengutronix Kernel Team , Fabio Estevam , devicetree@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/7] ARM: dts: imx: keep the SY7636A VCOM on Message-ID: <20261026083058.04173f10@kemnade.info> In-Reply-To: <20261026003918.155321-2-pmazzini@gmail.com> References: <20261026003918.155321-1-pmazzini@gmail.com> <20261026003918.155321-2-pmazzini@gmail.com> X-Mailer: Claws Mail 4.3.1 (GTK 3.24.49; aarch64-unknown-linux-gnu) X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 26 Oct 2026 00:39:12 +0000 Pablo Mazzini wrote: > The SY7636A hwmon driver turns VCOM on at probe. The reMarkable 2, Kobo > Libra H2O and Tolino Vision 5 have had the rails on so far. Mark VCOM > always-on before the driver stops doing it. > > Signed-off-by: Pablo Mazzini > --- > arch/arm/boot/dts/nxp/imx/e70k02.dtsi | 1 + > arch/arm/boot/dts/nxp/imx/imx7d-remarkable2.dts | 1 + > 2 files changed, 2 insertions(+) > > diff --git a/arch/arm/boot/dts/nxp/imx/e70k02.dtsi b/arch/arm/boot/dts/nxp/imx/e70k02.dtsi > index dc7ff108aa85..bd9c6c6fa117 100644 > --- a/arch/arm/boot/dts/nxp/imx/e70k02.dtsi > +++ b/arch/arm/boot/dts/nxp/imx/e70k02.dtsi > @@ -154,6 +154,7 @@ sy7636: pmic@62 { > regulators { > reg_epdpmic: vcom { > regulator-name = "vcom"; > + regulator-always-on; > }; > }; > }; No, please not. That regulator is in practice used with a not yet upstreamed driver for the EPDC on that platform used to deal with the current kernels fp9931 / tps65185 drivers. So it is very welcome to have it not always turned on. > diff --git a/arch/arm/boot/dts/nxp/imx/imx7d-remarkable2.dts b/arch/arm/boot/dts/nxp/imx/imx7d-remarkable2.dts > index ff9d50942884..6cf5603c0752 100644 > --- a/arch/arm/boot/dts/nxp/imx/imx7d-remarkable2.dts > +++ b/arch/arm/boot/dts/nxp/imx/imx7d-remarkable2.dts > @@ -327,6 +327,7 @@ sy7636a: pmic@62 { > regulators { > reg_epdpmic: vcom { > regulator-name = "vcom"; > + regulator-always-on; > regulator-boot-on; > }; > }; Here the situation is a bit different. If I remember correctly, there is some special EPD logic in userspace on top of some ordinary kernel display driver. But thesse things are missing is devicetree?! But that might need to learn to deal with regulator enabling/disabling. Regulator always on is probably not desired here, either. Regards, Andreas