From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpbgjp3.qq.com (smtpbgjp3.qq.com [54.92.39.34]) (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 949D43E6DEB for ; Fri, 28 Aug 2026 08:48:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=54.92.39.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787906902; cv=none; b=jdOjaZPxA+aEEuuibc1pvtGeYRu+YIF15LEikv+wmKK5pe79FZDm94UBDfR1JeG689fJt95bgb2ES5LsNba/WoVgbKU9geJMvHUaYVbLlzJXqNs1pm3w0A2yNE03LubXqfJ/mcWRjREulUIk/z90XUKjX190P4a+1ymrzlJ2w3I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787906902; c=relaxed/simple; bh=n0vihTnAb2IrmDGaMWU8fgHcATScRlf7XF7nt65nmdU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=rH1HnQCPby5JSz6B3JAzEBkYaYIVJhp3hU1jmrPEWSwOwvTK2n0eFnLuEsXL6nZV/MCgZ/BgEyvEEpAvSBLMS5Yg7mRIMApQFw5J2+j1w6l4DYAAeTRfe2eVhk4nM3A/kMn5khZv1H64Jw/rHE2T5yPmbcnxGomrbyZ6hYKl+dE= 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=hFOJGeq8; arc=none smtp.client-ip=54.92.39.34 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="hFOJGeq8" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=airkyi.com; s=altu2504; t=1787906872; bh=92lwE17e0FOpQsP6OniGlzehqwbaj82P3AEnE+KFgZY=; h=From:To:Subject:Date:Message-Id; b=hFOJGeq8tp+fHbez7X+nfUShR2b8D7SyiokkoAUTlljO8fZs14ahJUsB/f3ZW/YXJ s+P1ccr1NV6Y6FwSUKgQTM1eQpb/CKKZRY87Sj8YMPkvZ702Giuhbkgszmi//tuMfW iAe/jO9mR12ltromIuyBJ2P3qFReCRkNZJLMDyIs= 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: Nt4eoHGnUdqyKXXPE31b6Qx/NeZ+JnzmateFrjaUpXA3B1LtQjPedxRa hX3ysFGpf6UX3B/OxhE2MSch7DCdwOGqGymYdaJEBWgVGIgOKsap702MAfv7daVV9rx6HPy sNDvWDuEGL9biL3b4SSeBppHf1e9l7DdbyX9PKcXQfd8RgcpoGrRsId6MiTEXRAtn5NprzH mFOoIc2v3c979UEVkF7vQ4TB7lUFh3xzJCkoQ8/kDjWqFpQaILR4IRCAGXlSyj7o2UNgbFu bEuoOFuOUoJPpHUGn2UjeFFamjYfCy9btuUoVYvLHszpyzg+9wL7Tau/p9QyQtlYYyUV8gf tfp5hjJTxk58oiiKx36w8UriYE3GYb/bxVGRJ32Plm3tavBCFeGrAslL9osI0juGXPlM3W0 4vIH+S6hV/tbmi0qRBmsUzXhmFkyDdB7kAnKQ/28wuWgRv4DBuF8dJcRE4pnvnSGx6isWxO armhRayTnX9x7OO2i64LhH2+zPlj3Lp2wTK3wiZNhVivIeJfAmfJQan2Z+jR4UE85diTsmr y2Dmzhi29kqpJAAO268S+vnhynRmExBUKEeFz1uNuLX7zaCQMb7PPP/ImSxWQTJIJMy8QMo Att4RvU3nxxOPhJ29u1TWe5H0vwYgVHN8TzVFn54U9I0JY4ccEaO+5YycbL8GB1qG4vVDN2 Wnef8NDFcGV3naTk262U7YSVAzgxCV86ZvlqRJ5aFLHOKxFGSO/1Y5fycukGb7tfGQR3aIY b3gaA5NDPPPrTkR6po8WKKa79sFzwqXVtNXme2CRd+fxvKhmqTJW+65yDwxgwZUDL/71DTQ /zR/aQi9a8NAQ03DkYi55wu7MIr0p2RW7t7bjlUhpZoEv13BWybqut0rDZZ2h9vFtActuES KmYTJA0vXSHcPQomADeKLzfP9LQ/2aiXSTPQhbn2kkvG/E9fB/9GLAh2MCg3FJfwsKkRY41 YMT3TeWPWObbJf/+Wy0fTvZYwOoWvjVDWeJLZqdKs0uGLrYOSe7OFalEfJXw2FIMHfaE= X-QQ-XMRINFO: MPJ6Tf5t3I/ylTmHUqvI8+Wpn+Gzalws3A== X-QQ-RECHKSPAM: 0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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