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=-6.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY 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 74F00C31E49 for ; Mon, 17 Jun 2019 03:06:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 51D95208E3 for ; Mon, 17 Jun 2019 03:06:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727608AbfFQDGO (ORCPT ); Sun, 16 Jun 2019 23:06:14 -0400 Received: from Mailgw01.mediatek.com ([1.203.163.78]:8652 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1727383AbfFQDGO (ORCPT ); Sun, 16 Jun 2019 23:06:14 -0400 X-UUID: 0b2b5341301845fbaedf068b07628bff-20190617 X-UUID: 0b2b5341301845fbaedf068b07628bff-20190617 Received: from mtkcas32.mediatek.inc [(172.27.4.253)] by mailgw01.mediatek.com (envelope-from ) (mailgw01.mediatek.com ESMTP with TLS) with ESMTP id 924756873; Mon, 17 Jun 2019 11:06:05 +0800 Received: from mtkcas09.mediatek.inc (172.21.101.178) by MTKMBS31N2.mediatek.inc (172.27.4.87) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Mon, 17 Jun 2019 11:06:03 +0800 Received: from [172.21.77.4] (172.21.77.4) by mtkcas09.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Mon, 17 Jun 2019 11:06:03 +0800 Message-ID: <1560740762.25168.3.camel@mtksdaap41> Subject: Re: [PATCH v3, 26/27] drm/mediatek: add clock property check before get it From: CK Hu To: CC: Philipp Zabel , Rob Herring , Matthias Brugger , "David Airlie" , Daniel Vetter , Mark Rutland , , , , , Date: Mon, 17 Jun 2019 11:06:02 +0800 In-Reply-To: <1559734986-7379-27-git-send-email-yongqiang.niu@mediatek.com> References: <1559734986-7379-1-git-send-email-yongqiang.niu@mediatek.com> <1559734986-7379-27-git-send-email-yongqiang.niu@mediatek.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Yongqiang: On Wed, 2019-06-05 at 19:43 +0800, yongqiang.niu@mediatek.com wrote: > From: Yongqiang Niu > > This patch add clock property check before get it In the binding document [1], clock is required property. In this patch, you change it to optional property. I think you should change the binding document and describe _WHY_ do you do this. [1] https://www.kernel.org/doc/Documentation/devicetree/bindings/display/mediatek/mediatek%2Cdisp.txt Regards, CK > > Signed-off-by: Yongqiang Niu > --- > drivers/gpu/drm/mediatek/mtk_drm_ddp.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp.c > index 9986c61..28274d2 100644 > --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp.c > +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp.c > @@ -689,10 +689,12 @@ static int mtk_ddp_probe(struct platform_device *pdev) > for (i = 0; i < 10; i++) > ddp->mutex[i].id = i; > > - ddp->clk = devm_clk_get(dev, NULL); > - if (IS_ERR(ddp->clk)) { > - dev_err(dev, "Failed to get clock\n"); > - return PTR_ERR(ddp->clk); > + if (of_find_property(dev->of_node, "clocks", &i)) { > + ddp->clk = devm_clk_get(dev, NULL); > + if (IS_ERR(ddp->clk)) { > + dev_err(dev, "Failed to get clock\n"); > + return PTR_ERR(ddp->clk); > + } > } > > regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);