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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 18EF0C433EF for ; Tue, 7 Jun 2022 07:48:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Date:CC:To:From:Subject:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=C/fDWM+IlQr6Jo/gbpU9xLUEozLXRneywMpgEoWdDFg=; b=NjeU/HCo2WNGLe jjA8fySz6yJqfMQd+eWu4JhVkdd66emr+VLxDb749Ucvrh4Wq6qlFrCNXO3hz8ROJet1GFsRtUgun vVOLXbkzt05Rt8AaEzeCo1K6RksqM6Qg6pxRw7oQ6OaM0z0hIPt8DOD9A3ZsXnKexVLlwRaFkjGmI naJa0ltS1rTlqw7F/PUgUh4PDuHtd7w5gcPfOyb2bknL/KHTfxK7UuDF5ZRqvxAYghdodMfcJCVLX +Tk7T79mjmwcMarBlHjVY2JHe/aF3vf/sBJ4lpSjrZR9dIrSXgQ1xTXprMFWuTB6VXUGxC7YV2JtZ MezHfT0PzJa9CPQWDllg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nyTvv-005ZXI-Vc; Tue, 07 Jun 2022 07:47:24 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nyTvr-005ZUb-S6; Tue, 07 Jun 2022 07:47:21 +0000 X-UUID: cb67215c543b4e0290c9e60f08264a21-20220607 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.5,REQID:bb9175ec-9a7a-4ab5-a256-efe0e330e1e0,OB:0,LO B:0,IP:0,URL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,RULE:Release_Ham,ACTI ON:release,TS:0 X-CID-META: VersionHash:2a19b09,CLOUDID:2ea5e8e4-2ba2-4dc1-b6c5-11feb6c769e0,C OID:IGNORED,Recheck:0,SF:nil,TC:nil,Content:0,EDM:-3,IP:nil,URL:0,File:nil ,QS:0,BEC:nil X-UUID: cb67215c543b4e0290c9e60f08264a21-20220607 Received: from mtkcas67.mediatek.inc [(172.29.193.45)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 608213774; Tue, 07 Jun 2022 00:47:10 -0700 Received: from mtkmbs11n1.mediatek.inc (172.21.101.185) by MTKMBS62DR.mediatek.inc (172.29.94.18) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 7 Jun 2022 00:47:09 -0700 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by mtkmbs11n1.mediatek.inc (172.21.101.185) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.792.3; Tue, 7 Jun 2022 15:47:07 +0800 Received: from mtksdccf07 (172.21.84.99) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.792.3 via Frontend Transport; Tue, 7 Jun 2022 15:47:07 +0800 Message-ID: Subject: Re: [PATCH v10 18/21] drm/mediatek: Add mt8195 Embedded DisplayPort driver From: CK Hu To: Rex-BC Chen , Guillaume Ranquet , Chun-Kuang Hu , "Philipp Zabel" , David Airlie , "Daniel Vetter" , Rob Herring , "Krzysztof Kozlowski" , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Matthias Brugger , Chunfeng Yun , "Kishon Vijay Abraham I" , Vinod Koul , "Helge Deller" , Jitao shi CC: Markus Schneider-Pargmann , , , , , , , Date: Tue, 7 Jun 2022 15:47:07 +0800 In-Reply-To: <20220523104758.29531-19-granquet@baylibre.com> References: <20220523104758.29531-1-granquet@baylibre.com> <20220523104758.29531-19-granquet@baylibre.com> X-Mailer: Evolution 3.28.5-0ubuntu0.18.04.2 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220607_004719_957219_C7A79EC1 X-CRM114-Status: GOOD ( 24.59 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, Rex: On Mon, 2022-05-23 at 12:47 +0200, Guillaume Ranquet wrote: > From: Markus Schneider-Pargmann > > This patch adds a 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 > Jason-JH.Lin . > > Signed-off-by: Markus Schneider-Pargmann > Signed-off-by: Guillaume Ranquet > --- [snip] > + > +static int mtk_dp_hpd_sink_event(struct mtk_dp *mtk_dp) > +{ > + ssize_t ret; > + u8 sink_count; > + bool locked; > + u8 link_status[DP_LINK_STATUS_SIZE] = {}; > + u32 sink_count_reg = DP_SINK_COUNT_ESI; > + u32 link_status_reg = DP_LANE0_1_STATUS; > + > + ret = drm_dp_dpcd_readb(&mtk_dp->aux, sink_count_reg, > &sink_count); > + if (ret < 0) { > + drm_err(mtk_dp->drm_dev, "Read sink count failed: > %ld\n", ret); > + return ret; > + } > + > + ret = drm_dp_dpcd_read(&mtk_dp->aux, link_status_reg, > link_status, > + sizeof(link_status)); > + if (!ret) { > + drm_err(mtk_dp->drm_dev, "Read link status failed: > %ld\n", > + ret); > + return ret; > + } > + > + locked = drm_dp_channel_eq_ok(link_status, > + mtk_dp->train_info.lane_count); > + if (!locked && mtk_dp->train_state > > MTK_DP_TRAIN_STATE_TRAINING_PRE) Before enter this function, mtk_dp->train_state is set to MTK_DP_TRAIN_STATE_STARTUP, so this never happen, drop this. > + mtk_dp->train_state = MTK_DP_TRAIN_STATE_TRAINING_PRE; > + > + if (link_status[1] & DP_REMOTE_CONTROL_COMMAND_PENDING) > + drm_dp_dpcd_writeb(&mtk_dp->aux, > DP_DEVICE_SERVICE_IRQ_VECTOR, > + DP_REMOTE_CONTROL_COMMAND_PENDING); > + > + if (DP_GET_SINK_COUNT(sink_count) && > + (link_status[2] & DP_DOWNSTREAM_PORT_STATUS_CHANGED)) { > + mtk_dp->train_info.check_cap_count = 0; > + mtk_dp->train_state = MTK_DP_TRAIN_STATE_CHECKEDID; Why change state from MTK_DP_TRAIN_STATE_STARTUP to MTK_DP_TRAIN_STATE_CHECKEDID? In mtk_dp_train_handler(), mtk_dp_parse_capabilities() is true then change to MTK_DP_TRAIN_STATE_CHECKEDID. Give a reason why these two are different. Regards, CK > + msleep(20); > + } > + > + return 0; > +} > + _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel