From patchwork Thu Feb 6 18:14:27 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Ceresoli X-Patchwork-Id: 13963459 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 A91E8C0219B for ; Thu, 6 Feb 2025 18:15:12 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2534810E905; Thu, 6 Feb 2025 18:15:12 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="lBoVSeHl"; dkim-atps=neutral Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8891810E90B for ; Thu, 6 Feb 2025 18:15:10 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id C97AF442D7; Thu, 6 Feb 2025 18:15:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1738865709; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=8iJmfJohMLskNWh1/d0vxg24JxdxKf1x+OOa7rjoPoQ=; b=lBoVSeHlKoZKgObkr/7yH+eB6a28/qBL2c815XIuOrLvGMzwIO27CvahjbLLJROTvzCE5L 3YotwQGDyNa6viU6GczZ7FATkIvf6fxX4rgB7bhbgZ8cHCmB3uCGKyLRPxFjHQ47iqZG1I 94jMS/fhat15/+DcEg8+cFPfIR7V8/Pn9qJXL2Ry9LWrsDHyb+kZ1nYyOgWAz468z3mAh7 IPmWTzzP2wZVS/bJpqm7lgpZRA8eTtMJ5iPH3dfwvphiPTbt7y9pNdG3ZcVnlC3XtwybOh UkkZX6nQW/s8PqE2cmf9S9xN42UgSc01janAnUjiCVEiOSz5fxKe92B+Ql/XVg== From: Luca Ceresoli Date: Thu, 06 Feb 2025 19:14:27 +0100 Subject: [PATCH v6 12/26] drm/bridge: allow bridges to be informed about added and removed bridges MIME-Version: 1.0 Message-Id: <20250206-hotplug-drm-bridge-v6-12-9d6f2c9c3058@bootlin.com> References: <20250206-hotplug-drm-bridge-v6-0-9d6f2c9c3058@bootlin.com> In-Reply-To: <20250206-hotplug-drm-bridge-v6-0-9d6f2c9c3058@bootlin.com> To: Simona Vetter , Inki Dae , Jagan Teki , Marek Szyprowski , Catalin Marinas , Will Deacon , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Daniel Thompson , Andrzej Hajda , Jonathan Corbet , Sam Ravnborg , Boris Brezillon , Nicolas Ferre , Alexandre Belloni , Claudiu Beznea , Jessica Zhang Cc: Paul Kocialkowski , Maxime Ripard , Dmitry Baryshkov , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Thomas Zimmermann , David Airlie , =?utf-8?q?Herv=C3=A9_Codina?= , Thomas Petazzoni , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Paul Kocialkowski , Luca Ceresoli X-Mailer: b4 0.14.2 X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgddvjedtkecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfitefpfffkpdcuggftfghnshhusghstghrihgsvgenuceurghilhhouhhtmecufedtudenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhephfffufggtgfgkfhfjgfvvefosehtjeertdertdejnecuhfhrohhmpefnuhgtrgcuvegvrhgvshholhhiuceolhhutggrrdgtvghrvghsohhlihessghoohhtlhhinhdrtghomheqnecuggftrfgrthhtvghrnhepieeiuedvffetgfeuudelheeutefggfejieettdetteekueeuueeukeevvedvueevnecukfhppedvrgdtvdemieejtdemvddtvddtmegvrgdtudemhegrgedtmedvughfieemrgdulegvmedutgejgeenucevlhhushhtvghrufhiiigvpeelnecurfgrrhgrmhepihhnvghtpedvrgdtvdemieejtdemvddtvddtmegvrgdtudemhegrgedtmedvughfieemrgdulegvmedutgejgedphhgvlhhopegluddvjedrtddruddrudgnpdhmrghilhhfrhhomheplhhutggrrdgtvghrvghsohhlihessghoohhtlhhinhdrtghomhdpnhgspghrtghpthhtohepfeekpdhrtghpthhtoheptggrthgrlhhinhdrmhgrrhhinhgrshesrghrmhdrtghomhdprhgtphhtthhopehsrdhhrghuvghrsehpvghnghhuthhrohhnihigrdguvgdprhgtphhtthhopegrlhgvgigrnhgurhgvrdgsvghllhhonhhisegsohhothhlihhnrdgtohhmp dhrtghpthhtoheptghlrghuughiuhdrsggviihnvggrsehtuhigohhnrdguvghvpdhrtghpthhtohepmhdrshiihihprhhofihskhhisehsrghmshhunhhgrdgtohhmpdhrtghpthhtoheptghorhgsvghtsehlfihnrdhnvghtpdhrtghpthhtohepshhimhhonhgrsehffhiflhhlrdgthhdprhgtphhtthhopegurhhiqdguvghvvghlsehlihhsthhsrdhfrhgvvgguvghskhhtohhprdhorhhg X-GND-Sasl: luca.ceresoli@bootlin.com 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" In preparation for allowing bridges to be added to and removed from a DRM card without destroying the whole card, add a new DRM bridge function called on addition and removal of bridges. Signed-off-by: Luca Ceresoli --- Changed in v6: - rebased fixing conflicts Changed in v5: - fixed kerneldoc errors This patch was added in v4. --- drivers/gpu/drm/drm_bridge.c | 12 ++++++++++++ include/drm/drm_bridge.h | 23 +++++++++++++++++++++++ 2 files changed, 35 insertions(+) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index b0834b8644284e5f7751cec81724af849b4180e7..1955a231378050abf1071d74a145831b425c47c5 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -207,12 +207,18 @@ LIST_HEAD(bridge_list); */ void drm_bridge_add(struct drm_bridge *bridge) { + struct drm_bridge *br, *tmp; + mutex_init(&bridge->hpd_mutex); if (bridge->ops & DRM_BRIDGE_OP_HDMI) bridge->ycbcr_420_allowed = !!(bridge->supported_formats & BIT(HDMI_COLORSPACE_YUV420)); + list_for_each_entry_safe(br, tmp, &bridge_list, list) + if (br->funcs->bridge_event_notify) + br->funcs->bridge_event_notify(br, DRM_EVENT_BRIDGE_ADD, bridge); + mutex_lock(&bridge_lock); list_add_tail(&bridge->list, &bridge_list); mutex_unlock(&bridge_lock); @@ -249,10 +255,16 @@ EXPORT_SYMBOL(devm_drm_bridge_add); */ void drm_bridge_remove(struct drm_bridge *bridge) { + struct drm_bridge *br, *tmp; + mutex_lock(&bridge_lock); list_del_init(&bridge->list); mutex_unlock(&bridge_lock); + list_for_each_entry_safe(br, tmp, &bridge_list, list) + if (br->funcs->bridge_event_notify) + br->funcs->bridge_event_notify(br, DRM_EVENT_BRIDGE_REMOVE, bridge); + mutex_destroy(&bridge->hpd_mutex); } EXPORT_SYMBOL(drm_bridge_remove); diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index 1561347c4991dac6022319774510f9560c9283c3..ad7ba444a13e5ecf16f996de3742e4ac67dc21f1 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -56,6 +56,11 @@ enum drm_bridge_attach_flags { DRM_BRIDGE_ATTACH_NO_CONNECTOR = BIT(0), }; +enum drm_bridge_event_type { + DRM_EVENT_BRIDGE_ADD, + DRM_EVENT_BRIDGE_REMOVE, +}; + /** * struct drm_bridge_funcs - drm_bridge control functions */ @@ -729,6 +734,24 @@ struct drm_bridge_funcs { struct drm_bridge *bridge, bool enable, int direction); + /** + * @bridge_event_notify: + * + * Notify that another bridge is being added or removed. + * + * This callback is optional. Bridges implementing it must always + * check whether the event refers to a bridge they actually need to + * interact with. + * + * @bridge: bridge being notified + * @event: event happened (add/remove bridge) + * @event_bridge: the bridge mentioned by the event (i.e. the + * bridge being added or removed) + */ + void (*bridge_event_notify)(struct drm_bridge *bridge, + enum drm_bridge_event_type event, + struct drm_bridge *event_bridge); + /** * @debugfs_init: *