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 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 AB1E2EB7EB2 for ; Wed, 4 Mar 2026 09:52:03 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 12C1310E5F3; Wed, 4 Mar 2026 09:52:03 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=airkyi.com header.i=@airkyi.com header.b="bAMsaVJU"; dkim-atps=neutral X-Greylist: delayed 554 seconds by postgrey-1.36 at gabe; Wed, 04 Mar 2026 09:51:58 UTC Received: from smtpbgbr2.qq.com (smtpbgbr2.qq.com [54.207.22.56]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9C55410E5F3 for ; Wed, 4 Mar 2026 09:51:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=airkyi.com; s=altu2504; t=1772617914; bh=OToeNz4t2oXNHYHV6Pu5IF6zpl5lN3hD9z93ek1ZgZE=; h=From:To:Subject:Date:Message-Id; b=bAMsaVJUtr0/i6nfQB0P37nzzbQa5foYS//xpEJbXAEURpfL4pQHSt+GUuFxGndli kzxR4PY6bisyWCn6pyOmkG6VSow/4TGlNfdHjetTWFroemWMX+ROUAvz12Vo6FdibN V9DnLBkgke8JEAFDFZIzZVxjq8+8Xzd6EgiW4tl8= X-QQ-mid: esmtpsz11t1772617328tcb692adf X-QQ-Originating-IP: eI4sld9gb/MYkTQBflnzN3OZF8EXbfFF/XhG0TH49SM= Received: from DESKTOP-8BT1A2O.localdomain ( [58.22.7.114]) by bizesmtp.qq.com (ESMTP) with id ; Wed, 04 Mar 2026 17:42:03 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 0 X-BIZMAIL-ID: 2636057480523225983 From: Chaoyi Chen To: Heikki Krogerus , Greg Kroah-Hartman , Dmitry Baryshkov , Peter Chen , Luca Ceresoli , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Vinod Koul , Kishon Vijay Abraham I , Heiko Stuebner , Sandy Huang , Andy Yan , Yubing Zhang , Frank Wang , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Amit Sunil Dhamne , Dragan Simic , Johan Jonker , Diederik de Haas , Peter Robinson , Hugh Cole-Baker Cc: linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-phy@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, dri-devel@lists.freedesktop.org, Chaoyi Chen Subject: [PATCH v15 1/9] drm/bridge: Implement generic USB Type-C DP HPD bridge Date: Wed, 4 Mar 2026 17:41:44 +0800 Message-Id: <20260304094152.92-2-kernel@airkyi.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20260304094152.92-1-kernel@airkyi.com> References: <20260304094152.92-1-kernel@airkyi.com> X-QQ-SENDSIZE: 520 Feedback-ID: esmtpsz:airkyi.com:qybglogicsvrgz:qybglogicsvrgz6b-0 X-QQ-XMAILINFO: M3vv73qU6a4uywa5T2AnRL6DEMO0bcRrHUcORiSLZO8U6NB0iT3Ymn6t 35rRlYbcknhxP2Ei62LVW/M6KjNhe9DYgRDq0eKvU1Nn0jUdu/8RCkZOiDnTv5fonlbSsSq XLdEFPKmHPYYiCnLmp1wd0hZ79+9bGODn3H0vAW1K7TmRjSET/rhnyhcb2CRZ7kR5MC3jcH kK9w4wNSxQHKpr8nqzfP2EmXALE8cNvfVV464B77oBUP0p+bA+OvKc7Cbvpi70kfwxJ0ov5 QIKHq7MuwL8Pr6kWjjvh4xQqITUUik/Lq/CrVXs2GkLUwzCmJua1AS5qEjEEpPIYMjJtkCf V7cWyW6RdnEfT6QBUc6kTldo6ZNHHsmZJkTFeMe8zNcTkvecQJDUYDINlZPicMRIfG/Ix5f tkuF8mkbImqPqhG6+l9oRW61FLnVpbUQS1Kze3V5TbjaTugL7tQ1eSbWQvqW/OFZgZ2xDb3 YocsppQXa7jWwoo1uOisACTSR1gQ6DgLGiLKD3FzDmnavmjZmQzoJlXS2CrM/uGfQrFyV4N 8o5Gm4YK2maNkjlvdLbM8U/Js4zGTFntZQR2Rzywpdw2GJOavGsZrYn8n2S60g/xZBGdEzu mFXB/ilhmay+ABEcu2dB5jk25pysl+Kdyshkf5bff+CxJAgvOzC2cniVBkJkb+qowuN+RDT s+u23nzhZRrtaafHSj1xQImz/OR8L2GO76pIqzrN6sk0XRWlgIsHmo6bRXSVhc76cNmHXyN pCBZrJGCv6rAFnx5oO9f0q3GWgXZ0EtuHVZs2papkOj3ZZcnVvruSm3LuifXESCt2CFU4+V 5wX9eefCPANcoca9g/0OftPDaHD4IgK1D1gGt4vdWLKI5UkEyhYm0JEBdaIpbJOdN+vbmp+ j+X4HkMkSOEUjZ49I/9T015ni20+ReyPthLYxlImy6D/46RXqhmhCRzDkM88pPpmlppsMWH jUHRgrr2+8P5TaeeZInpCKeIzGxdszL2t9sckiAbEipu4lBNt/NKz/wuYtt2x5vZqHVSq2Z DvuMc1jPj8w9UOMrsR X-QQ-XMRINFO: NyFYKkN4Ny6FuXrnB5Ye7Aabb3ujjtK+gg== X-QQ-RECHKSPAM: 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Chaoyi Chen The HPD function of Type-C DP is implemented through drm_connector_oob_hotplug_event(). For embedded DP, it is required that the DRM connector fwnode corresponds to the Type-C port fwnode. To describe the relationship between the DP controller and the Type-C port device, we usually using drm_bridge to build a bridge chain. Now several USB-C controller drivers have already implemented the DP HPD bridge function provided by aux-hpd-bridge.c, it will build a DP HPD bridge on USB-C connector port device. But this requires the USB-C controller driver to manually register the HPD bridge. If the driver does not implement this feature, the bridge will not be create. So this patch implements a generic DP HPD bridge based on aux-hpd-bridge.c. It will monitor Type-C bus events, and when a Type-C port device containing the DP svid is registered, it will create an HPD bridge for it without the need for the USB-C controller driver to implement it. Signed-off-by: Chaoyi Chen Reviewed-by: Heikki Krogerus --- (no changes since v14) Changes in v13: - Only register drm dp hpd bridge for typec port altmode device. (no changes since v12) Changes in v11: - Switch to using typec bus notifiers. (no changes since v10) Changes in v9: - Remove the exposed DRM_AUX_HPD_BRIDGE option, and select DRM_AUX_HPD_TYPEC_BRIDGE when it is available. - Add more commit comment about problem background. Changes in v8: - Merge generic DP HPD bridge into one module. --- drivers/gpu/drm/bridge/Kconfig | 10 ++++ drivers/gpu/drm/bridge/Makefile | 1 + .../gpu/drm/bridge/aux-hpd-typec-dp-bridge.c | 49 +++++++++++++++++++ 3 files changed, 60 insertions(+) create mode 100644 drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index a250afd8d662..559487aa09a9 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -30,6 +30,16 @@ config DRM_AUX_HPD_BRIDGE Simple bridge that terminates the bridge chain and provides HPD support. +if DRM_AUX_HPD_BRIDGE +config DRM_AUX_HPD_TYPEC_BRIDGE + tristate + depends on TYPEC || !TYPEC + default TYPEC + help + Simple bridge that terminates the bridge chain and provides HPD + support. It build bridge on each USB-C connector device node. +endif + menu "Display Interface Bridges" depends on DRM && DRM_BRIDGE diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile index c7dc03182e59..a3a0393d2e72 100644 --- a/drivers/gpu/drm/bridge/Makefile +++ b/drivers/gpu/drm/bridge/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_DRM_AUX_BRIDGE) += aux-bridge.o obj-$(CONFIG_DRM_AUX_HPD_BRIDGE) += aux-hpd-bridge.o +obj-$(CONFIG_DRM_AUX_HPD_TYPEC_BRIDGE) += aux-hpd-typec-dp-bridge.o obj-$(CONFIG_DRM_CHIPONE_ICN6211) += chipone-icn6211.o obj-$(CONFIG_DRM_CHRONTEL_CH7033) += chrontel-ch7033.o obj-$(CONFIG_DRM_CROS_EC_ANX7688) += cros-ec-anx7688.o diff --git a/drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c b/drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c new file mode 100644 index 000000000000..d915e0fb0668 --- /dev/null +++ b/drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0+ +#include +#include +#include + +#include + +static int drm_typec_bus_event(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct device *dev = (struct device *)data; + struct typec_altmode *alt = to_typec_altmode(dev); + + if (action != BUS_NOTIFY_ADD_DEVICE) + goto done; + + /* + * alt->dev.parent->parent : USB-C controller device + * alt->dev.parent : USB-C connector device + */ + if (is_typec_port_altmode(&alt->dev) && alt->svid == USB_TYPEC_DP_SID) + drm_dp_hpd_bridge_register(alt->dev.parent->parent, + to_of_node(alt->dev.parent->fwnode)); + +done: + return NOTIFY_OK; +} + +static struct notifier_block drm_typec_event_nb = { + .notifier_call = drm_typec_bus_event, +}; + +static void drm_aux_hpd_typec_dp_bridge_module_exit(void) +{ + bus_unregister_notifier(&typec_bus, &drm_typec_event_nb); +} + +static int __init drm_aux_hpd_typec_dp_bridge_module_init(void) +{ + bus_register_notifier(&typec_bus, &drm_typec_event_nb); + + return 0; +} + +module_init(drm_aux_hpd_typec_dp_bridge_module_init); +module_exit(drm_aux_hpd_typec_dp_bridge_module_exit); + +MODULE_DESCRIPTION("DRM TYPEC DP HPD BRIDGE"); +MODULE_LICENSE("GPL"); -- 2.51.1