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 8636CC61DC6 for ; Fri, 28 Aug 2026 08:48:39 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E010E10F2E8; Fri, 28 Aug 2026 08:48:38 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=airkyi.com header.i=@airkyi.com header.b="nuPu3R6R"; dkim-atps=neutral Received: from bg5.exmail.qq.com (bg5.exmail.qq.com [43.154.209.5]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8F54310F2E8 for ; Fri, 28 Aug 2026 08:48:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=airkyi.com; s=altu2504; t=1787906873; bh=92lwE17e0FOpQsP6OniGlzehqwbaj82P3AEnE+KFgZY=; h=From:To:Subject:Date:Message-Id; b=nuPu3R6RGBxTvSwneXV+5w/V05jY5QhBFOze733JxyiPmtzDNtW36KwlXFWK5P+W3 BNQOnOhOHeMaO9am8XEX+Cp3HpQwFJUFP/lbSDeC3VYjB8ky7hPsylcq99AJsN5Kw5 AhVIETookMNWknvsHIN2YpMiIRvL69ygE0EaJoio= X-QQ-mid: zesmtpgz6t1787906871t6f8f5f8b X-QQ-Originating-IP: 3JGdevLTu8iXxaqXX2RzHlTwRgpYv/D9UneAY+H2Hqc= Received: from DESKTOP-8BT1A2O.localdomain ( [61.154.14.86]) by bizesmtp.qq.com (ESMTP) with id ; Fri, 28 Aug 2026 16:47:46 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 0 X-BIZMAIL-ID: 8549069541952634456 From: Chaoyi Chen To: Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Luca Ceresoli , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Sandy Huang , =?UTF-8?q?Heiko=20St=C3=BCbner?= , Andy Yan , Vinod Koul , Chaoyi Chen , Sebastian Reichel , Nicolas Frattaroli , Heikki Krogerus Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-phy@lists.infradead.org Subject: [PATCH v7 1/7] drm/bridge: aux-hpd-bridge: Add drm_dev_has_dp_hpd_bridge() Date: Fri, 28 Aug 2026 16:47:31 +0800 Message-Id: <20260828084737.565-2-kernel@airkyi.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20260828084737.565-1-kernel@airkyi.com> References: <20260828084737.565-1-kernel@airkyi.com> X-QQ-SENDSIZE: 520 Feedback-ID: zesmtpgz:airkyi.com:qybglogicsvrgz:qybglogicsvrgz6b-0 X-QQ-XMAILINFO: NZJ7CNmHCWa7RLgstN1K22jaNYiNnIa2echZ8/83Wc8X4yHv1dWzDh8E 6EYtuITktB7FhOWZL50BPuvgn3Qcz3hE9NEf4ZwTF1Lvs41nBFn+cUwUF1fdykT7ef/vSOc 2o+Qr2KpQ/hFHE6Yo/1JQf6osfOQW4eVoYXVDx6GjjhjzoAEJL7LDyYp278S/jObZft28r3 Zdcepqmu+kTlPNnIds5a3Z0sl4JHwzGayL6lQw+0DwsNHY/nj5S+kmlmqJ/OCCS0wtr2eew tANlpsOJHEVF9lwikrvG0kyhD/JVc8Nxlz4vWt4zNBTqzMmt19alw0wYLJgIYpQVUZiv908 C1rjkluMHeH7lljd8q7IQzfJtcZeD6PGoAtpd6igxkyz2qxpzyxYKh3Sqc3ok/TmTHDTbIP guRSvVoXxWrGUWNMRLoAU7XS5uVbPAI8Dved5Mt9hviJI8gIyHtI8DMmuGPs1D8ODoGq0iD Fo3ftkCkR4MYoUZ3blVJ2Txhv7vCvpXSznB7qRHHDbQbwCxO1skoCw/Lf+gjYvKHVEG80nc /l4V3MsNcXQwyRBxO8QpEPGzOljsgySiEb1YSSBu4rR0hRrxoJv6wGjicDEFMkl/0xIT1c7 XbDuvJ65ubT1rKxRum4+B1Mr5c4ZM40UE/caDoFRd55IscBslcIwBsI5slvYnJ1vn1uEU++ w4iGzkjMAcSrvzMQ+1Ttxe1algP10sW2Lvqgl8mO3y1M/KKiAO8lnEhLcG44kIrry7rsWV5 tW3oGXuHz9eezVZJ9Wo0b2nck3OgeudIihX6eB24a//WpHw3eR9xNO4g1tldmuOO4jcbOcK dGoN8FtVF0vsf8//ievmGLA5byBSrba3w3Vb1oACyqwFZ4/VEvNRONXglECjY2/rpPeV3Ky /xZTYcjzvR+tOG6+usFQzFVqpmVBeW4KOVXFIyTvNDZxByCfGaSzum2317p4CYxCNCL1RZH UpkxmF0cynUNct7vlVPIcXXZ6AKE9DJ++pdA1Uq9bAtMLzmvkgdA2DOCskZSxPpNRRb0= X-QQ-XMRINFO: OWPUhxQsoeAVwkVaQIEGSKwwgKCxK/fD5g== 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 Add a new API to check whether a DisplayPort HPD bridge has already been registered. This helps avoid duplicate registration of the same HPD bridge, although the current framework allows doing so. Suggested-by: Sebastian Reichel Reviewed-by: Sebastian Reichel Tested-by: Sebastian Reichel Signed-off-by: Chaoyi Chen --- (no changes since v7) --- drivers/gpu/drm/bridge/aux-hpd-bridge.c | 42 ++++++++++++++++++++++++- include/drm/bridge/aux-bridge.h | 6 ++++ 2 files changed, 47 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/aux-hpd-bridge.c b/drivers/gpu/drm/bridge/aux-hpd-bridge.c index f02a38a2638a..a56c88eba005 100644 --- a/drivers/gpu/drm/bridge/aux-hpd-bridge.c +++ b/drivers/gpu/drm/bridge/aux-hpd-bridge.c @@ -12,6 +12,8 @@ #include #include +#define DRM_AUX_HPD_BRIDGE_NAME "dp_hpd_bridge" + static DEFINE_IDA(drm_aux_hpd_bridge_ida); struct drm_aux_hpd_bridge_data { @@ -36,6 +38,44 @@ static void drm_aux_hpd_bridge_free_adev(void *_adev) auxiliary_device_uninit(_adev); } +static int hpd_bridge_match(struct device *dev, const void *data) +{ + const struct device_node *np = data; + struct auxiliary_device *adev; + + if (!dev_is_auxiliary(dev)) + return 0; + + adev = to_auxiliary_dev(dev); + if (strcmp(adev->name, DRM_AUX_HPD_BRIDGE_NAME)) + return 0; + + return adev->dev.platform_data == np; +} + +/** + * drm_dev_has_dp_hpd_bridge - check whether a HPD DisplayPort bridge is registered + * @parent: device instance providing this bridge + * @np: device node pointer corresponding to this bridge instance + * + * Walk the children of @parent and check whether a HPD DisplayPort bridge for + * the given @np has already been registered via devm_drm_dp_hpd_bridge_add(). + * + * Return: true if a HPD bridge for @parent / @np already exists, false otherwise + */ +bool drm_dev_has_dp_hpd_bridge(struct device *parent, struct device_node *np) +{ + struct device *child; + + child = device_find_child(parent, np, hpd_bridge_match); + if (child) { + put_device(child); + return true; + } + return false; +} +EXPORT_SYMBOL_GPL(drm_dev_has_dp_hpd_bridge); + /** * devm_drm_dp_hpd_bridge_alloc - allocate a HPD DisplayPort bridge * @parent: device instance providing this bridge @@ -63,7 +103,7 @@ struct auxiliary_device *devm_drm_dp_hpd_bridge_alloc(struct device *parent, str } adev->id = ret; - adev->name = "dp_hpd_bridge"; + adev->name = DRM_AUX_HPD_BRIDGE_NAME; adev->dev.parent = parent; adev->dev.release = drm_aux_hpd_bridge_release; adev->dev.platform_data = of_node_get(np); diff --git a/include/drm/bridge/aux-bridge.h b/include/drm/bridge/aux-bridge.h index c2f5a855512f..cca07a8e2d45 100644 --- a/include/drm/bridge/aux-bridge.h +++ b/include/drm/bridge/aux-bridge.h @@ -25,6 +25,7 @@ struct auxiliary_device *devm_drm_dp_hpd_bridge_alloc(struct device *parent, str int devm_drm_dp_hpd_bridge_add(struct device *dev, struct auxiliary_device *adev); struct device *drm_dp_hpd_bridge_register(struct device *parent, struct device_node *np); +bool drm_dev_has_dp_hpd_bridge(struct device *parent, struct device_node *np); void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status); #else static inline struct auxiliary_device *devm_drm_dp_hpd_bridge_alloc(struct device *parent, @@ -44,6 +45,11 @@ static inline struct device *drm_dp_hpd_bridge_register(struct device *parent, return NULL; } +static inline bool drm_dev_has_dp_hpd_bridge(struct device *parent, struct device_node *np) +{ + return false; +} + static inline void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status) { } -- 2.53.0