From patchwork Wed Mar 8 16:39:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jagan Teki X-Patchwork-Id: 13166111 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 CA140C678D5 for ; Wed, 8 Mar 2023 16:40:35 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id DE8E310E693; Wed, 8 Mar 2023 16:40:34 +0000 (UTC) Received: from mail-pj1-x1029.google.com (mail-pj1-x1029.google.com [IPv6:2607:f8b0:4864:20::1029]) by gabe.freedesktop.org (Postfix) with ESMTPS id 30D3410E693 for ; Wed, 8 Mar 2023 16:40:32 +0000 (UTC) Received: by mail-pj1-x1029.google.com with SMTP id l1so17052984pjt.2 for ; Wed, 08 Mar 2023 08:40:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amarulasolutions.com; s=google; t=1678293632; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=+udTIu1ct3G8jeCaDXjf5KrilADcli7EoE7on9WYgu0=; b=PqE7wz15JeimxJbi1nS3Z5y1VJWeHTpMNvtbETJBe7hr0bZ7OupYtjzXoib7WXF9gr TNQBqrNGHxb7VZnOILg5cb5vq5QonxU2MyavRPGdakUGRDIVPcCCKD83M23FiI9srCgP 4eFSTlUR3i878tZD3iSuy6txBeBKHtIBDZTCM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678293632; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=+udTIu1ct3G8jeCaDXjf5KrilADcli7EoE7on9WYgu0=; b=65vfi0pSn52PAZ3Ki20HNiaZe2GqzLiTJ71WZzB9Z5GEl+5GAsEqaA9hRO2PtLwEci MUDu6j8FLTQzOdv80eKWYcHB4Hkl0GcCkQnq6sI08wKt0WUktatYNpjH+ydUcMqnEOzA /tZtZanNvDHPGA8ERKoFno5XpJ3SyJsyb8Osv4xZRIyGyRSqDFASFDZNC/kWBnpJF5Nn Sg1NHVu9OGu+GVv7jop/3Qb9+QCANoKLSeClTtxUseYQqpPqgPDxC6PmWDq2+KIGxhOT PPQKBEwMi5Mgb/3qYpi28lIDXeArjQkOB4Y9kKmZyHKWX2Vp8Wze5qHw2AaDjmpVNPPv Tuhg== X-Gm-Message-State: AO0yUKWbBEbtdybxdCUGhGHgp0zJSLwdNZktTseNkq4dhZq2Mbeja1hJ 8azmx2qu6sVlao4BZF639tz6Mg== X-Google-Smtp-Source: AK7set94DrWst1cTG4qj6qYVtYEgKPswGeGtyDVSiS+srxpAeVAalvzdisDZENFBAsbZKRkhzC6+4w== X-Received: by 2002:a17:902:ea11:b0:19c:e05a:ea6 with SMTP id s17-20020a170902ea1100b0019ce05a0ea6mr22145963plg.56.1678293631715; Wed, 08 Mar 2023 08:40:31 -0800 (PST) Received: from localhost.localdomain ([2405:201:c00a:a8a1:b545:91cc:80b2:f9fe]) by smtp.gmail.com with ESMTPSA id kq3-20020a170903284300b0019b9a075f1fsm10046540plb.80.2023.03.08.08.40.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 08 Mar 2023 08:40:31 -0800 (PST) From: Jagan Teki To: Andrzej Hajda , Inki Dae , Marek Szyprowski , Neil Armstrong , Marek Vasut , Maxime Ripard Subject: [PATCH v16 02/16] drm: exynos: dsi: Lookup OF-graph or Child node devices Date: Wed, 8 Mar 2023 22:09:39 +0530 Message-Id: <20230308163953.28506-3-jagan@amarulasolutions.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230308163953.28506-1-jagan@amarulasolutions.com> References: <20230308163953.28506-1-jagan@amarulasolutions.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-samsung-soc@vger.kernel.org, Matteo Lisi , linux-amarula , Seung-Woo Kim , Frieder Schrempf , Kyungmin Park , dri-devel@lists.freedesktop.org, Adam Ford , Jagan Teki Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" In general, for MIPI DSI there are three ways to represent the pipeline for an upstream bridge to find the connected downstream panel or bridge. 1. Child panel or bridge as a conventional device tree child node. 2. Child panel or bridge as an OF-graph port node. 3. Child panel or bridge as an OF-graph ports node. There are three different downstream panels or bridges that are possible to connect an upstream DSI host bridge - DSI Panel, DSI Bridge, and I2C-Configured DSI bridge. An example of the downstream panel represented as a child node, &dsi { compatible = "samsung,exynos5433-mipi-dsi"; ports { port@0 { reg = <0>; dsi_to_mic: endpoint { remote-endpoint = <&mic_to_dsi>; }; }; }; panel@0 { reg = <0>; }; }; An example of the downstream bridge represented as a port node, &i2c4 { bridge@2c { compatible = "ti,sn65dsi84"; ports { port@0 { reg = <0>; bridge_in_dsi: endpoint { remote-endpoint = <&dsi_out_bridge>; data-lanes = <1 2>; }; }; port@2 { reg = <2>; bridge_out_panel: endpoint { remote-endpoint = <&panel_out_bridge>; }; }; }; }; }; &dsi { compatible = "fsl,imx8mm-mipi-dsim"; port { dsi_in_lcdif: endpoint@0 { reg = <0>; remote-endpoint = <&lcdif_out_dsi>; }; dsi_out_bridge: endpoint@1 { reg = <1>; remote-endpoint = <&bridge_in_dsi>; }; }; }; An example of the downstream bridge represented as a ports node, &dsi { compatible = "fsl,imx8mm-mipi-dsim"; ports { port@0 { reg = <0>; dsi_in_lcdif: endpoint@0 { reg = <0>; remote-endpoint = <&lcdif_out_dsi>; }; }; port@1 { reg = <1>; dsi_out_bridge: endpoint { remote-endpoint = <&bridge_in_dsi>; }; }; }; In, summary it is possible to represent all three downstream slaves devices using OF-graph port or ports node however only DSI Panel and DSI Bridge are possible but not possible to represent I2C-Configured DSI bridge child nodes since I2C-Configure bridges are child of I2C node, not upstream DSI host bridge and it is must represent them endpoint port linking. This indeed means, the OF-graph port or ports representation is mandatory for I2C-Configured DSI bridges. This patch tries to add an OF-graph port or ports representation detection code on top of existing child node detection. It is possible to replace the entire detection code using existing drm_of helper drm_of_find_panel_or_bridge but it will break the Exynos DSI since the pipeline doesn't support OF-graph port or ports node. Overall, this patch has a combination of child and OF-graph pipeline detections in order to support the backward compatibility of Exynos DSI child node and i.MX8M Mini/Nano/Plus OF-graph port or ports node pipelines. This is the first common DSI host bridge driver that needs to support all possible downstream connection pipeline combinations. Tested-by: Marek Szyprowski Reviewed-by: Marek Vasut Signed-off-by: Jagan Teki --- Changes for v16: - collect TB from Marek S - collect RB from Marek V - fix multiline comment Changes for v15: - droped from drm_of - added in exynos dsi - updated commit messages Changes for v13, v12: - none Changes for v11: - drop extra line Changes for v10: - new patch drivers/gpu/drm/exynos/exynos_drm_dsi.c | 38 +++++++++++++++++++++++-- 1 file changed, 36 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c index df15501b1075..bb0d2502ea02 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c @@ -1470,18 +1470,52 @@ static int exynos_dsi_host_attach(struct mipi_dsi_host *host, struct device *dev = dsi->dev; struct drm_encoder *encoder = &dsi->encoder; struct drm_device *drm = encoder->dev; + struct device_node *np = dev->of_node; + struct device_node *remote; struct drm_panel *panel; int ret; - panel = of_drm_find_panel(device->dev.of_node); + /* + * Devices can also be child nodes when we also control that device + * through the upstream device (ie, MIPI-DCS for a MIPI-DSI device). + * + * Lookup for a child node of the given parent that isn't either port + * or ports. + */ + for_each_available_child_of_node(np, remote) { + if (of_node_name_eq(remote, "port") || + of_node_name_eq(remote, "ports")) + continue; + + goto of_find_panel_or_bridge; + } + + /* + * of_graph_get_remote_node() produces a noisy error message if port + * node isn't found and the absence of the port is a legit case here, + * so at first we silently check whether graph presents in the + * device-tree node. + */ + if (!of_graph_is_present(np)) + return -ENODEV; + + remote = of_graph_get_remote_node(np, 1, 0); + +of_find_panel_or_bridge: + if (!remote) + return -ENODEV; + + panel = of_drm_find_panel(remote); if (!IS_ERR(panel)) { dsi->out_bridge = devm_drm_panel_bridge_add(dev, panel); } else { - dsi->out_bridge = of_drm_find_bridge(device->dev.of_node); + dsi->out_bridge = of_drm_find_bridge(remote); if (!dsi->out_bridge) dsi->out_bridge = ERR_PTR(-EINVAL); } + of_node_put(remote); + if (IS_ERR(dsi->out_bridge)) { ret = PTR_ERR(dsi->out_bridge); DRM_DEV_ERROR(dev, "failed to find the bridge: %d\n", ret);