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 D704DC433EF for ; Tue, 26 Jul 2022 08:37:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237942AbiGZIha (ORCPT ); Tue, 26 Jul 2022 04:37:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229749AbiGZIha (ORCPT ); Tue, 26 Jul 2022 04:37:30 -0400 Received: from mailgw01.mediatek.com (unknown [60.244.123.138]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B45B42AC2; Tue, 26 Jul 2022 01:37:28 -0700 (PDT) X-UUID: e80651ba2cde4989bf7630e6063b8e64-20220726 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.8,REQID:7ac7fa29-1ede-4cb9-a7ca-d5f2ff8137a1,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:0f94e32,CLOUDID:76ff0cee-db04-4499-9fdf-04ef44b9468c,C OID:IGNORED,Recheck:0,SF:nil,TC:nil,Content:0,EDM:-3,IP:nil,URL:0,File:nil ,QS:nil,BEC:nil,COL:0 X-UUID: e80651ba2cde4989bf7630e6063b8e64-20220726 Received: from mtkexhb01.mediatek.inc [(172.21.101.102)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1551725302; Tue, 26 Jul 2022 16:37:24 +0800 Received: from mtkmbs11n1.mediatek.inc (172.21.101.186) by mtkmbs10n1.mediatek.inc (172.21.101.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.792.15; Tue, 26 Jul 2022 16:37:22 +0800 Received: from mtksdccf07 (172.21.84.99) by mtkmbs11n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.792.15 via Frontend Transport; Tue, 26 Jul 2022 16:37:22 +0800 Message-ID: <9140e0b37c71bfa8193d2177a1cc044df4761e15.camel@mediatek.com> Subject: Re: [PATCH v14 05/10] drm/mediatek: Add MT8195 Embedded DisplayPort driver From: CK Hu To: Rex-BC Chen , "chunkuang.hu@kernel.org" , "p.zabel@pengutronix.de" , "daniel@ffwll.ch" , "robh+dt@kernel.org" , "krzysztof.kozlowski+dt@linaro.org" , "mripard@kernel.org" , "tzimmermann@suse.de" , "matthias.bgg@gmail.com" , "deller@gmx.de" , "airlied@linux.ie" CC: "msp@baylibre.com" , "granquet@baylibre.com" , Jitao Shi =?UTF-8?Q?=28=E7=9F=B3=E8=AE=B0=E6=B6=9B=29?= , "wenst@chromium.org" , "angelogioacchino.delregno@collabora.com" , LiangXu Xu =?UTF-8?Q?=28=E5=BE=90=E4=BA=AE=29?= , "dri-devel@lists.freedesktop.org" , "linux-mediatek@lists.infradead.org" , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-fbdev@vger.kernel.org" , Project_Global_Chrome_Upstream_Group Date: Tue, 26 Jul 2022 16:37:21 +0800 In-Reply-To: References: <20220712111223.13080-1-rex-bc.chen@mediatek.com> <20220712111223.13080-6-rex-bc.chen@mediatek.com> <6232f0fc15bc1057aab68523e5eb63e10b3a2802.camel@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-fbdev@vger.kernel.org On Tue, 2022-07-26 at 11:30 +0800, Rex-BC Chen wrote: > On Mon, 2022-07-25 at 17:23 +0800, CK Hu wrote: > > 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] > > > > > + > > > +/* > > > + * We need to handle HPD signal in eDP even though eDP is a > > > always > > > connected > > > + * device. Besides connected status, there is another feature > > > for > > > HPD signal - > > > + * HPD pulse: it presents an IRQ from sink devices to source > > > devices > > > (Refer to > > > + * 5.1.4 of DP1.4 spec). > > > + */ > > > +static irqreturn_t mtk_dp_hpd_isr_handler(struct mtk_dp *mtk_dp) > > > +{ > > > + bool hpd_change = false; > > > + u32 irq_status = mtk_dp_swirq_get_clear(mtk_dp) | > > > + mtk_dp_hwirq_get_clear(mtk_dp); > > > + struct mtk_dp_train_info *train_info = &mtk_dp->train_info; > > > + > > > + if (!irq_status) > > > + return IRQ_HANDLED; > > > + > > > + if (irq_status & MTK_DP_HPD_INTERRUPT) > > > + train_info->irq_sta.hpd_inerrupt = true; > > > + if (irq_status & MTK_DP_HPD_CONNECT || > > > + irq_status & MTK_DP_HPD_DISCONNECT) > > > + hpd_change = true; > > > + > > > + if (!(hpd_change)) > > > + return IRQ_WAKE_THREAD; > > > + > > > + if (mtk_dp_plug_state(mtk_dp)) > > > > mtk_dp_plug_state() is called only here, and prevent function call > > in > > isr handler, so squash mtk_dp_plug_state() into this function. > > > > Hello CK, > > Thanks for review. > > I would like to keep this because we will use this function for > mtk_dp_plug_state_avoid_pulse() in dp patch. Use train_info->cable_plugged_in instead of calling mtk_dp_plug_state() because I think train_info->cable_plugged_in is synced with mtk_dp_plug_state(). > > > > + train_info->cable_plugged_in = true; > > > + else > > > + train_info->cable_plugged_in = false; > > > + > > > + train_info->cable_state_change = true; > > > + > > > + return IRQ_WAKE_THREAD; > > > +} > > > + > > > +static irqreturn_t mtk_dp_hpd_event(int hpd, void *dev) > > > +{ > > > + struct mtk_dp *mtk_dp = dev; > > > + u32 irq_status; > > > + > > > + irq_status = mtk_dp_read(mtk_dp, MTK_DP_TOP_IRQ_STATUS); > > > + > > > + if (!irq_status) > > > + return IRQ_HANDLED; > > > + > > > + if (irq_status & RGS_IRQ_STATUS_TRANSMITTER) > > > + return mtk_dp_hpd_isr_handler(mtk_dp); > > > > Prevent function call in isr handler, squash > > mtk_dp_hpd_isr_handler() > > into this function. > > > > Is this really necessary? We also modify this function in following > patches. I think it's not a good idea to expand this. mtk_dp_hpd_isr_handler() is only called in this function, is it really necessary to separate this to a independent function? The function call would increase jump instruction and stack push/pop instruction. I think we should not do many things in isr handler. I've reviewed the later patch and the later patch should be modified according to this. Regards, CK > > BRs, > Bo-Chen > > > Regards, > > CK > > > > > + > > > + return IRQ_HANDLED; > > > +} > > > + > > > > > >