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 05ED7D1D862 for ; Thu, 4 Dec 2025 06:32:27 +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=tnGvdgabwSIu+i1OtiOksigRJkfBAJHpGnwVCXS2P5o=; b=CVxCQ8dfpXEkwTZoE+mTAGTVlq n0BB2k2Grv36Xty0ZdgInqijHG7TZw2obks9wrjHWW+/jT+BqXUmHNfXgb7DbpkzInlnefCw6pwbB Fnr9P1K85CiA0YEq9dNKi9LRL6wN/TAC1Kz7RPHOM74Qt2WGb2sDIEnPcYIW8cTTVJSrbYvoGWLiN LBBa3SorgUX7u6j/2XELrOKxgIpy8KhY9d8FHEJfxgMQSemqxEI3KoopIa6V98CHVUpeHxa4bEu85 f37IRafseUrTNKEmHvmIAs8PAPPQbSl6QeVpSs+F6aSvJb1ffyPxcILjHgXYpdXOfWYijCOZ7TLOE v355NZoA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vR2t4-00000007Y6K-2d2f; Thu, 04 Dec 2025 06:32:22 +0000 Received: from smtpbg154.qq.com ([15.184.224.54]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vR2sr-00000007Y3P-1Y0J; Thu, 04 Dec 2025 06:32:20 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=airkyi.com; s=altu2504; t=1764829895; bh=tnGvdgabwSIu+i1OtiOksigRJkfBAJHpGnwVCXS2P5o=; h=From:To:Subject:Date:Message-Id; b=Wly4Kw73/pv+BwUIyoj+tHuX+rgURbCqcvwg8PEJdStO0ld6E+50DJSc9qnl4p09O WB7Yc72L/TMVPepBxMq5gVA/GgwiN6Xja3eBWJ6Q8D6NeP89CNiB+8N2NV2qEyei9L ChWiMvd/xJNydB2l0JHGG3VjU11eOpdyQFxKkb+Q= X-QQ-mid: esmtpsz21t1764829893t62e7fee3 X-QQ-Originating-IP: 4q1w9+bgCS0LGdPqbRhxoDeHWokBVZZFuy5QX+5KrZI= Received: from DESKTOP-8BT1A2O.localdomain ( [58.22.7.114]) by bizesmtp.qq.com (ESMTP) with id ; Thu, 04 Dec 2025 14:31:30 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 0 X-BIZMAIL-ID: 9830896031001290684 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: [RESEND PATCH v11 03/11] drm/bridge: Implement generic USB Type-C DP HPD bridge Date: Thu, 4 Dec 2025 14:31:01 +0800 Message-Id: <20251204063109.104-4-kernel@airkyi.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20251204063109.104-1-kernel@airkyi.com> References: <20251204063109.104-1-kernel@airkyi.com> X-QQ-SENDSIZE: 520 Feedback-ID: esmtpsz:airkyi.com:qybglogicsvrgz:qybglogicsvrgz6b-0 X-QQ-XMAILINFO: NXrWVyDJhsq8W2ET7yKoB0uKe+t43ldi95YEsav3te1+YgTaUAhdPit/ wW8P7UNNkhp/tUczZ+xY3LBRTO3XgOXRUOAaYlaZQkZodZYKG+7by0BN+SkWo1zq6eXM+yB xQBvTbXFCeVgQr/mXpiZhs38TBwZRdQenC4jUJ8dZf88FilOCPOnc4b9jPhg6lkk38am/kF anhYsnbZvk1cHxC8G6HJp45ldYBCtX8B1sZdd4Q+HLOQqn46UlDJ6NWhPq4hJR5iZ5MhOTP q/SXwNhY0IStqu7quPygst7enrFa2DOpOcj4KYKESWQBxqQnG0DMHBTCgdN6I4fUoBM54JN aMCaY8dTTW+LWj+uFYOPYZ45Tb0a1kzsT5AKxjYHOeczRM97kxEp0Ayls1FdhO3hprpJYJU DyOtaNbSdkQUJLQCee/MF9RcJuhcwciHcNE+n1AgnpFEO7TzCSLdzMPB1Eidbnzl96p07sW gHnRQy7t5EhYQ585ZN4DdEVS7pCamipV87fgiDUywFPjeNY6/7LvtoorvV8PA8U8fXeL+yQ 4AqxXzCX3murRPVBA8EdCj/VAkM1SENQ+vhDNhxZCR09f5iinBmoSwXCxix8Kn4hUQ1Ewh1 1dOc4twAlJFWed1sNyFImmioBjnpVDGUftgKsdfL3KoKIBk9Pp5GyZ+8S/9m99lFhxifJiz sn8z6Ripq44Nd1GeTREUbGKycXseCjMqrXLIByxEn8ZGzwbAgqHgIM3wwn9ZH8gL3m2rIb0 pSG1VyHiw8aRt4YUFMimJ4b7/WOTI4KKJR+ykrmBafN9UCD2NyV66deyTLM9WPKIO1a1a0v cRjbJFjuwHtbyQQTI/zDsUSUIbttk9nymBksVP3QYXBQRZtHuSJa+6l/0UFb0eFD1YyYs+o xbSH/6rUhA+v/7p1C2a5wb6TsVR7qhYYlGDOmCEedvL79xK2eCaTyzESeRjG+aAv2nIjI/f IWcADVUDg5CZoBhHXuE9jD7JZJXQBNdJYL1rNNVUE/qxMV5n0N01XZmDntz/BUZn50QCtbc NDtDrSedR4tIqowh9RKLckj3mY/M0= X-QQ-XMRINFO: OWPUhxQsoeAVDbp3OJHYyFg= X-QQ-RECHKSPAM: 0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251203_223210_018836_1745BABE X-CRM114-Status: GOOD ( 21.00 ) 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 --- 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 | 51 +++++++++++++++++++ 3 files changed, 62 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..94be3d5f69e9 --- /dev/null +++ b/drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c @@ -0,0 +1,51 @@ +// 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; + + if (is_typec_partner_altmode(&alt->dev) || alt->svid != USB_TYPEC_DP_SID) + goto done; + + /* + * alt->dev.parent->parent : USB-C controller device + * alt->dev.parent : USB-C connector device + */ + 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