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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 DF217D2CE17 for ; Mon, 8 Dec 2025 01:56:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/ITohFNSR7lZRzb2jcZzCyseW4V9moYl6cPe0u/7eVQ=; b=hQRHOEg4Yoys6+yQNBC9JkdwkS p8N0q5vof3R1yFxfqo3dVJVA50XvowVFEeDyB7GvGkcOsGUPJ0xNSOwtFAy+cO6Ju9e4JbpMsDMGb eOVzMS+YMetI4yVY+YYZk6Xff/GmUTH31F4qSLpUHl79AFeNQICxZUmWu0ZzoHl9M9awdLsQQmL1F NIaTfnxcmBNUrHR5ZtRdv1/rm1oYLSllbEk0SqtazhyMFwLE8rK9QKr4EQUh7YjbWrT7fjSKddSTi R3j+Js6IqQlpDlkYe7a1N7E7/Gl4pCinWSy+UaaQNxUvMr3hJ/EdEHB3AnF5YyvjZRz4r98U6qzMa /UnxFQUA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vSQU2-0000000CPr7-1Nz8; Mon, 08 Dec 2025 01:56:14 +0000 Received: from smtpbg151.qq.com ([18.169.211.239]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vSQTr-0000000CPlk-3059; Mon, 08 Dec 2025 01:56:06 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=airkyi.com; s=altu2504; t=1765158926; bh=/ITohFNSR7lZRzb2jcZzCyseW4V9moYl6cPe0u/7eVQ=; h=From:To:Subject:Date:Message-Id; b=VdO0Jn5MduDfj9k13G+diYn9Won2YEFhmTJZ9z5AI9UgkeM6cpL62Pvidk3Fzrgrc gAE/IWbmrXl1jkZYt25/7G5W48dietLPzNdpbhjtHm1vMoYwPeQNo79a1zs9+bDn9J iKkpiL+DNqtH9EcEBMoF9QvIzsKSE39MzSDIZ3LQ= 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: MShfLn39PbN2yDcQfiZSX7HG0VX8cENqmu7rD5ouHqomjF9F/FNkYRjc zfulT/+yCyE2LYfFSdrjYcKDCnqYI055D3tS2LTd5ueZXKRFtGc9UuQqi9Ha5CKNuuqGpzf g55+s2bFrGesK8idGBhNs2xUuqsD1AfW3GyHVE1ds3KTvW5Miw21sjW77oYeQ5x+ZF1IEPI vhxrdaNojQ1KtC+5VK1MF1GbuNMmkQIDsLESJ39Nplj9/uPhpCx10fxwtaFlkVRrrcZiXeg 31RkOSp55zaJu+xONNvAl8Tl08007o8MUI+mB5T3Xw9G6eH8nK9XrCVU2mJfAxdFMf6BMDv lRaXVa8RCTJ9021DnphpYQVDr+s/MtrMv+3P3ffGE+uota00Jgzs09GhGQq3uDKYysf3KYV ILxxP7dDEOamYNZkLeTMp5AG3tK+Nr/JRB+zr+ltA+ASTM4czq/27WrKX8YCOx/xZ5bJdWJ l4HpLS48MbKK1PMR/HQ0bPKoL0JJNzyXdzRoUOBbyDKLEjxC+TVB+bhFSBBkmn5avOQWOWF UCrpBVhn2IS0pEDpfSSWxlXbSAskN7JiZGHBm9BBH5ccoDI8P2SoXDK/rvzc4j7Uk5s0DVx Rl8wqlBM+s8Qb2piLRSZhYShBhzJnuQVAsX/oSAX9Unj/kNLqShcvBf1be2XayyRE6/eyc9 yQc/NAuLFRD0wQYWYXUCpFQpZxoqMBGG7trFqEHoQq+58JrtaG6mDE2AvT1UI0tzfSxLZZD k8NEb/ETBBXiCLhd/ER5PcPdgHYjYMpwcbeco9G2QZDR30pnWULxXng0pzi3BXAiBph1ZgF hyJ/nolDF8z8wqNHoLz6lxLuvknfuEaoAtpgoWhSvdbcqxMOd3KrR9RE6RpW1aa5sa1oy1q s6cok4wAfaNP5C/eZyKVV28jhdGqycaFit6zeU9POdZyiLBwzg7pXRaGWVOTgWYcgAgfBAU ys/2GKabSP4Im0AemaQdTgkG4FXUW5XobKM/xDmEaSrSPL56J+hWKWi6GsqQh97EKS5mJAo FpzE/sXQ== X-QQ-XMRINFO: NS+P29fieYNw95Bth2bWPxk= X-QQ-RECHKSPAM: 0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251207_175604_379961_39136F74 X-CRM114-Status: GOOD ( 21.12 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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. +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