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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 788D2CCA48A for ; Mon, 25 Jul 2022 09:16:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233839AbiGYJQS (ORCPT ); Mon, 25 Jul 2022 05:16:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54684 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233128AbiGYJQQ (ORCPT ); Mon, 25 Jul 2022 05:16:16 -0400 Received: from mailgw01.mediatek.com (unknown [60.244.123.138]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13EFB12D1B; Mon, 25 Jul 2022 02:16:14 -0700 (PDT) X-UUID: 1cd5c103d0a945429bb35aa09b368dda-20220725 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.8,REQID:da636671-b920-42b5-addc-bff15833bc61,OB:0,LO B:0,IP:0,URL:0,TC:0,Content:0,EDM:0,RT:0,SF:45,FILE:0,RULE:Release_Ham,ACT ION:release,TS:45 X-CID-INFO: VERSION:1.1.8,REQID:da636671-b920-42b5-addc-bff15833bc61,OB:0,LOB: 0,IP:0,URL:0,TC:0,Content:0,EDM:0,RT:0,SF:45,FILE:0,RULE:Release_Ham,ACTIO N:release,TS:45 X-CID-META: VersionHash:0f94e32,CLOUDID:5e106cb3-06d2-48ef-b2dd-540836705165,C OID:7b9a55edaef9,Recheck:0,SF:28|17|19|48,TC:nil,Content:0,EDM:-3,IP:nil,U RL:0,File:nil,QS:nil,BEC:nil,COL:0 X-UUID: 1cd5c103d0a945429bb35aa09b368dda-20220725 Received: from mtkmbs10n1.mediatek.inc [(172.21.101.34)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1396310637; Mon, 25 Jul 2022 17:16:11 +0800 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.792.3; Mon, 25 Jul 2022 17:16:09 +0800 Received: from mtksdccf07 (172.21.84.99) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.792.15 via Frontend Transport; Mon, 25 Jul 2022 17:16:09 +0800 Message-ID: <378f904a445e90d65048ed07a1a55fd8c633f934.camel@mediatek.com> Subject: Re: [PATCH v14 05/10] drm/mediatek: Add MT8195 Embedded DisplayPort driver From: CK Hu To: Bo-Chen Chen , , , , , , , , , , CC: , , , , , , , , , , , , Date: Mon, 25 Jul 2022 17:16:09 +0800 In-Reply-To: <20220712111223.13080-6-rex-bc.chen@mediatek.com> References: <20220712111223.13080-1-rex-bc.chen@mediatek.com> <20220712111223.13080-6-rex-bc.chen@mediatek.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5-0ubuntu0.18.04.2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Bo-Chen: On Tue, 2022-07-12 at 19:12 +0800, Bo-Chen Chen wrote: > From: Markus Schneider-Pargmann > > This patch adds a embedded displayport driver for the MediaTek mt8195 > SoC. > > It supports the MT8195, the embedded DisplayPort units. It offers > DisplayPort 1.4 with up to 4 lanes. > > The driver creates a child device for the phy. The child device will > never exist without the parent being active. As they are sharing a > register range, the parent passes a regmap pointer to the child so > that > both can work with the same register range. The phy driver sets > device > data that is read by the parent to get the phy device that can be > used > to control the phy properties. > > This driver is based on an initial version by > Jitao shi > > Signed-off-by: Markus Schneider-Pargmann > Signed-off-by: Guillaume Ranquet > Signed-off-by: Bo-Chen Chen > --- [snip] > + > +static int mtk_dp_training(struct mtk_dp *mtk_dp) > +{ > + short max_retry = 50; > + int ret; > + > + do { > + ret = mtk_dp_train_start(mtk_dp); > + if (!ret) > + break; > + else if (ret != -EAGAIN) > + return ret; > + } while (--max_retry); mtk_dp_train_start() would never return -EAGAIN, so drop this while loop. Regards, CK > > + if (!max_retry) > + return -ETIMEDOUT; > + > + ret = mtk_dp_video_config(mtk_dp); > + if (ret) > + return ret; > + mtk_dp_video_enable(mtk_dp, true); > + > + return 0; > +} > +