From nobody Tue Dec 16 02:39:14 2025 Received: from smtpbgau1.qq.com (smtpbgau1.qq.com [54.206.16.166]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 845DB1D5147; Mon, 8 Dec 2025 01:55:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.206.16.166 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765158945; cv=none; b=r+aMK9tKY5iHxVq7UzMrmd2TaPQU89agyFjokWTF93oFwmY9NDlqLpR5GENMyZiSoBbrwLiHo7daf+3V0e3aeqwhwuBxF7+YTIJjRWDMmjiQI4UnpGHhrom3DsXIFnAWTjVc7RgMS3Dv0SC47rR4JBhzVtXwQzuUBr8NvHDLmLc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765158945; c=relaxed/simple; bh=oZxAKY069oSsoQIE/uXBSrlabu075v/j9Xbnbn4CQOw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=t00fHYoKAh9kr/nBRvEB70PvGIrOZL+ifBGXDNtmwqxFQgtoCzGAGQrMY3xqOTVsayNFmyi36pwPdFauIhQhB6av+T9hPU6DpXfRUDQ5unEHVC+e7/41ime1vOkjhPt9bByhlvKKJYIiwGi+Bvfe7C9c9CxIqPCbAbwnrGb5H7s= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=airkyi.com; spf=pass smtp.mailfrom=airkyi.com; dkim=pass (1024-bit key) header.d=airkyi.com header.i=@airkyi.com header.b=an/MTlNQ; arc=none smtp.client-ip=54.206.16.166 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=airkyi.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=airkyi.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=airkyi.com header.i=@airkyi.com header.b="an/MTlNQ" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=airkyi.com; s=altu2504; t=1765158925; bh=/ITohFNSR7lZRzb2jcZzCyseW4V9moYl6cPe0u/7eVQ=; h=From:To:Subject:Date:Message-Id; b=an/MTlNQtQs7hnsabvNn2iZxYiEQSpdGeYMNqu8huMHYHX4iHibOvJDfwLCAiOiks 5yeUAptyhV7OkXa6AHwI+cS4pMNDGyHYN7LDr4dmt1bOo0JsHdc8OmxoasnMXlw1Om Q5pa0u0TND1y/WrPFkrHwMIOEvI0Z+s3UVPYYGA4= X-QQ-mid: esmtpsz19t1765158924t760755d5 X-QQ-Originating-IP: 3roZbY8eqQltdEXFqjutnrbNDJ5RRJ4S3DkEoxdunYw= Received: from DESKTOP-8BT1A2O.localdomain ( [58.22.7.114]) by bizesmtp.qq.com (ESMTP) with id ; Mon, 08 Dec 2025 09:55:21 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 0 X-BIZMAIL-ID: 10138295490961143045 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 , Chaoyi Chen , Dragan Simic , Johan Jonker , Diederik de Haas , Peter Robinson 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 Subject: [PATCH v13 03/11] drm/bridge: Implement generic USB Type-C DP HPD bridge Date: Mon, 8 Dec 2025 09:54:52 +0800 Message-Id: <20251208015500.94-4-kernel@airkyi.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20251208015500.94-1-kernel@airkyi.com> References: <20251208015500.94-1-kernel@airkyi.com> X-QQ-SENDSIZE: 520 Feedback-ID: esmtpsz:airkyi.com:qybglogicsvrgz:qybglogicsvrgz6b-0 X-QQ-XMAILINFO: N4WhQbLQyIqSeMUvU2ikqO791RQnK4HKCJbvtZL2wTXWNNHCbSD1lMp5 txuz6BJFxYzn94HxTd+zuGPGDgtVBNRqGvdDhTi0IA/rIKmqJ1dS61GUmCnIuru0Wc5JGhv qZakWYH+V9AhmhD2R7xtM8fcA9bFP/eRPFcb45rOS3e35Yg4/k7cae/Jgu4zfeHSuvwwuSf fTEhFWYBkk+x7E9nr8NhrTR0iL/ZFRZSS+60QLz0HK8WL+HRyRMbDPDJ+PGzKMRKep5Ju7A lRazjpSSIzVK+BRBGH1CRck+w0xLZA4JTXCUTHw887EGGQz1qmSGEYGnwceJFcjAEad1Gi3 7y36dPOI1s0cicwcpwciVcex0mMUbmyJCLRQXsgNKfWkqO3GHccPx1BuGixzRTiMcWFIEuT iqe9eT4/lPNzjCxECoko2M4KLo/+YeoC0eWweZ+XsAU2wYnQrwdGMmm+Y/1SgXvTYOC0D48 QTDRXYLVN9fY9UNgUbD/LyDjwLBFH+2dHUD5GE/tTcJl+ld//5yTmE8UGfo/uOImaxWg4hG +OiGsxMai4NL6d0GGj+RlIJINM/xCSDzjUfGNjotw93KWHePShd6rjCL1WwPDwNo1vlNEjg 6NT+snu5e1SNO3965z1UcFADvSNZF7LMrfoRh62RSnVxB1LsQmeurpK3tMKr0sZD5ViDd5u syqxbqlryK4h5m0JDcw078IZtoqiVwbH32wfk+tvuuc2l+kOC/Wm62QycFmsy7Eda6eTwDE 6P/WKUFsfNBbUoKm9sn/Fx3lQvFTNCBkocnE08a4nrG32Er4sfg8MvifHRel+wJae2qbp+Z ZHySk8TF+miJHUJB3ny66DECVfw+rwQcpcUJ3YTKf/9SUpXdyV9RARs2HqhoJy3kr63eM0Z 5yPAdEGs2MsmvBtuVtINKUCG0hOFCIkZrhW1BrNLG7U/aI9fHrAQLNLBlu1uDdtQ+D4V9Tv TMTfMMVCeVaGFgH/01BP85+n4vmUtQ4XzPBxCH2iWv+8YmWjA5mAxMmiheGpWc1QVZGuKHY TAa6Ayjg== X-QQ-XMRINFO: OD9hHCdaPRBwq3WW+NvGbIU= X-QQ-RECHKSPAM: 0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" 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 --- 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. =20 +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 =20 diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makef= ile 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-$(CONFIG_DRM_AUX_BRIDGE) +=3D aux-bridge.o obj-$(CONFIG_DRM_AUX_HPD_BRIDGE) +=3D aux-hpd-bridge.o +obj-$(CONFIG_DRM_AUX_HPD_TYPEC_BRIDGE) +=3D aux-hpd-typec-dp-bridge.o obj-$(CONFIG_DRM_CHIPONE_ICN6211) +=3D chipone-icn6211.o obj-$(CONFIG_DRM_CHRONTEL_CH7033) +=3D chrontel-ch7033.o obj-$(CONFIG_DRM_CROS_EC_ANX7688) +=3D 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 =3D (struct device *)data; + struct typec_altmode *alt =3D to_typec_altmode(dev); + + if (action !=3D 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 =3D=3D 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 =3D { + .notifier_call =3D 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"); --=20 2.51.1