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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH, USER_AGENT_MUTT autolearn=ham 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 4523DC04AB6 for ; Tue, 28 May 2019 13:26:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E6AF20883 for ; Tue, 28 May 2019 13:26:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559050002; bh=MaqgcW6nL9RipUjfYMmDV89IlHXx7ZoyjtJFiqTck/g=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=yU65fhhLyZ1M+xl7XFxdpFKHhS4g43ZyEbpnLtOJ8jZFVAFFtODgZyVGL0xCbtZox b6icSQFDhTUqiD4mujEEI2HJuFv7a1sRImE1Sqj/DIaFdzwH0eSSR1iDzWqWZAAAOT j/15P2yRnRK6ZPSl8PBb4jhmGX8NdIqMmAqWIkCY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727585AbfE1N0l (ORCPT ); Tue, 28 May 2019 09:26:41 -0400 Received: from heliosphere.sirena.org.uk ([172.104.155.198]:43462 "EHLO heliosphere.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726973AbfE1N0k (ORCPT ); Tue, 28 May 2019 09:26:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sirena.org.uk; s=20170815-heliosphere; h=In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding: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=v+Z1R+Iyc3P0HugccnvG8WNIqOUHRpGpClXvCccCpcQ=; b=jzo5SZZBqDaLIZNrP1iMNepJv nQwqeGdVBggb9XPerGWoJuIcs2PnLAJxDWApUrS93wtxO7gILMbhNFV3B4Dj/1ZQCPIKDSDaPkdAg rzwDjCDIPVSWg7eFVkfSh/h6rS9e8JSUADmKxmYSdBtKqwLN/uW60iriNXuMfQfIUi39s=; Received: from cpc102320-sgyl38-2-0-cust46.18-2.cable.virginm.net ([82.37.168.47] helo=finisterre.sirena.org.uk) by heliosphere.sirena.org.uk with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hVc7c-0002VH-UU; Tue, 28 May 2019 13:26:32 +0000 Received: by finisterre.sirena.org.uk (Postfix, from userid 1000) id 22EBF440046; Tue, 28 May 2019 14:26:32 +0100 (BST) Date: Tue, 28 May 2019 14:26:32 +0100 From: Mark Brown To: Andy Duan Cc: "david@lechnology.com" , "rafael@kernel.org" , Robby Cai , "gregkh@linuxfoundation.org" , linux-kernel Subject: Re: Issue: regmap: use debugfs even when no device Message-ID: <20190528132632.GJ2456@sirena.org.uk> References: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="BOmey7/79ja+7F5w" Content-Disposition: inline In-Reply-To: X-Cookie: The other line moves faster. User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --BOmey7/79ja+7F5w Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, May 28, 2019 at 02:20:15AM +0000, Andy Duan wrote: > So on i.MX8MM/8QM/8QXP platforms, we catch the issue that user dump regmap registers without > power cause system hang. > Maybe revert the patch is more reasonable ? This is an issue with or without a device - you can have the same issue with devices that are powered off. Typically where power is dynamic the driver will use a register cache so the registers are always available. --BOmey7/79ja+7F5w Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAlztNwcACgkQJNaLcl1U h9D4nQf/Qm5/cL/GsDQzCdntAZ69L9JspITibd0eQuycfxNMcg5OWjoretBkbrPr h2HZjvd7xvjmj2TXPwQXAAffgUk5h68YBCCRjnGG93/ITIcJ4d89hMX9vllQdgYW kb9s2kBBX9NcSuLb6n9+IG1q90Bvs8CvImKOuBUKVJPcZ+cs4bvS0Q8CqrXrtiqt 8VZ3+u+PNNbzTzbwJy1T5lJJ/vnUC7lOq7sB5EkMDwQhF6FOJsBmOI5NQbZIdD6u h2Vkmg+ayW5N8IPcizLLyKchFHtq4ueeaQEF6d7DOoh06vGz2kLx5D/7lIcb967v QUvH7iI69CD3ctWFAyQmswJFDI/aJQ== =+B0c -----END PGP SIGNATURE----- --BOmey7/79ja+7F5w--