From patchwork Fri Mar 3 14:51:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jagan Teki X-Patchwork-Id: 658682 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 40D4EC7EE37 for ; Fri, 3 Mar 2023 14:52:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229968AbjCCOwd (ORCPT ); Fri, 3 Mar 2023 09:52:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37334 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230432AbjCCOw1 (ORCPT ); Fri, 3 Mar 2023 09:52:27 -0500 Received: from mail-pl1-x62e.google.com (mail-pl1-x62e.google.com [IPv6:2607:f8b0:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 077031ADF8 for ; Fri, 3 Mar 2023 06:52:26 -0800 (PST) Received: by mail-pl1-x62e.google.com with SMTP id i10so2875932plr.9 for ; Fri, 03 Mar 2023 06:52:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amarulasolutions.com; s=google; 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=75obg6WaKxGAouYp8L8vU99A5I1ZieLyIbshRx9ot/0=; b=nwx3nUHwxYB+MWEpPux9HLvk8V4noZ7L+o+7LujBV5Kj/aMUzpWTVRIoXDVdVIatL8 PxKHmTzFqu8hHKTC1Y9yr6DnGMfO/UldXSuEx6m7RuJioml+wq0PoBBNuEvEzipmdG01 y0qaUqzqQ1tzuVji8CliTx1YYQnKk2zjXQlhU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=75obg6WaKxGAouYp8L8vU99A5I1ZieLyIbshRx9ot/0=; b=7xkWXDmjsekdPcQqQ/ffy/5EOQrcsSh9EA+MlQAlpkiW+cyGRVByFoghX9a4P575hy eJijSAY9YaQXhhTXvjJm98fLrG2oRqI2QebIXZbQboRwHXuNAaso71Yy8EAY2XbV/0eg TIGT76J48kUUJwDqeij+F5rMTBAbFGGW0bxNkddelc67qdGRBKAm4gmCTgYwuq4lSCKI shSsQcmRjT2axMJd4NuCKjTG+vI760OlqdmYd8CYdU1r1o9/WS5fO65qJiTDoiee6Z/s 12KH6YiR/fqz2eP99vKxbS2MKOu6XmefApufa9ew9AnFKLoiK8RGw+Zsu4UN7A5DGQah tWXg== X-Gm-Message-State: AO0yUKVhtGv/IaLi0XkC/QUOzjm14XwguK8OWWlTW+vFWkQ3Kc+3iWKc pFUCOnquP+FR75iTlYR33tz1Qg== X-Google-Smtp-Source: AK7set9ddne/co5GxlXg9Z5y/8Uyd9N9Zo8lSmWtNpR1RY239kYYX6ZIxpoVDg7hxSfEjK9DP+o/yw== X-Received: by 2002:a05:6a20:5487:b0:c6:d37c:2a62 with SMTP id i7-20020a056a20548700b000c6d37c2a62mr2981782pzk.11.1677855145441; Fri, 03 Mar 2023 06:52:25 -0800 (PST) Received: from localhost.localdomain ([183.83.137.89]) by smtp.gmail.com with ESMTPSA id z4-20020a63e544000000b00502fd70b0bdsm1660856pgj.52.2023.03.03.06.52.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Mar 2023 06:52:24 -0800 (PST) From: Jagan Teki To: Andrzej Hajda , Inki Dae , Marek Szyprowski , Neil Armstrong , Marek Vasut , Maxime Ripard Cc: Seung-Woo Kim , Kyungmin Park , Frieder Schrempf , Tim Harvey , Adam Ford , Matteo Lisi , dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, linux-amarula , Jagan Teki Subject: [PATCH v15 02/16] drm: exynos: dsi: Lookup OF-graph or Child node devices Date: Fri, 3 Mar 2023 20:21:24 +0530 Message-Id: <20230303145138.29233-3-jagan@amarulasolutions.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230303145138.29233-1-jagan@amarulasolutions.com> References: <20230303145138.29233-1-jagan@amarulasolutions.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org 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. Signed-off-by: Jagan Teki --- 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..f44a5a702ad5 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);