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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 9D183C2D0DB for ; Mon, 20 Jan 2020 14:31:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6E10620678 for ; Mon, 20 Jan 2020 14:31:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727117AbgATObh (ORCPT ); Mon, 20 Jan 2020 09:31:37 -0500 Received: from metis.ext.pengutronix.de ([85.220.165.71]:59843 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726642AbgATObh (ORCPT ); Mon, 20 Jan 2020 09:31:37 -0500 Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1itY5X-0008BC-4k; Mon, 20 Jan 2020 15:31:35 +0100 Received: from ukl by ptx.hi.pengutronix.de with local (Exim 4.89) (envelope-from ) id 1itY5W-0001f3-2f; Mon, 20 Jan 2020 15:31:34 +0100 Date: Mon, 20 Jan 2020 15:31:34 +0100 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= To: Jitao Shi Cc: Thierry Reding , Matthias Brugger , linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, CK Hu , linux-mediatek@lists.infradead.org, sj.huang@mediatek.com Subject: Re: [PATCH v4 1/2] pwm: mtk_disp: fix pwm clocks not poweroff when disable pwm Message-ID: <20200120143134.yqojufklnack27xf@pengutronix.de> References: <20191217040237.28238-1-jitao.shi@mediatek.com> <20191217040237.28238-2-jitao.shi@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20191217040237.28238-2-jitao.shi@mediatek.com> User-Agent: NeoMutt/20170113 (1.7.2) 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 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, I fully agree to what Thierry said about the commit log. One more comment: On Tue, Dec 17, 2019 at 12:02:36PM +0800, Jitao Shi wrote: > @@ -194,14 +194,6 @@ static int mtk_disp_pwm_probe(struct platform_device *pdev) > if (IS_ERR(mdp->clk_mm)) > return PTR_ERR(mdp->clk_mm); > > - ret = clk_prepare(mdp->clk_main); > - if (ret < 0) > - return ret; > - > - ret = clk_prepare(mdp->clk_mm); > - if (ret < 0) > - goto disable_clk_main; > - > mdp->chip.dev = &pdev->dev; > mdp->chip.ops = &mtk_disp_pwm_ops; > mdp->chip.base = -1; After this there is: if (!mdp->data->has_commit) { mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug, ...); ... } So I wonder if dropping the clk_enables above is safe if there are some register accesses later on. Side note: The driver you're touching here is still using the legacy API. Would be great to convert it to .apply() instead. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ |