From nobody Thu Oct 9 04:46:25 2025 Received: from relay5-d.mail.gandi.net (relay5-d.mail.gandi.net [217.70.183.197]) (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 092B62E06EF for ; Fri, 20 Jun 2025 16:00:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.197 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750435207; cv=none; b=mMoa5gI5E5OkvjeMvqbt6zniEQyQCiL/w9XcJJLLeV7n6nj54MxUiUbnpBnc/UFDOPMrbNvcSW7kizNeUfUH94FvwsxUkIe17RYN66OlFMxtI2qafnU3zENGaq0ygIDituAWy1jzHm0qzu04bg2rK6AJWCXRlGSgW/eUAhMjIUE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750435207; c=relaxed/simple; bh=ed9q5r9QXX/tScB0hlRWC+iB7XI/aig1zTWd0nUKkJA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ufHHlhb98Rbl1lAPwXfuD4AN4jFCYrlFf66v8J+P6kNmTBqSzyLunGknHI339AmBzn2d6oaDEMidWkAX7VzBlIxXo/b/Cm0Pyzb4qO8w9jT6ZCP4QkoAsZtxiIaKtMw9ZCG52nmTJzdBtZ5U7Z3lyUziZak2SZxsMxK9F8JFlPk= ARC-Authentication-Results: i=1; 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bh=+8MtcpgSRqEBJiFr7cEobMUHzglh2pRSIimhGNGsWtk=; b=fbsN1Yz0thT+D2mN4A4tVovRyuNRGCm5/TbASFnv3W7Gxz623dSjaab8+Lx+t4tBm24iya YOBGxHNy4Y/cni2/WPbAs9bAzyraM0HdqcsobIRnxQy0/Y5aQAuLOF7fGYw1dDqR7mYZgq FV3Bi+SODaXzw0/W8Jl0OfXvpf6zKPmO6EPK7z165d/e0j3Qw/atfr1yxjL5gsKystTc6n jQjxuQbGl7Ad2sQ9jIuVO5kRWXVFDl+ZXXMM7+rzvXwqdYGiz7EkWT9j+k/AXE6EPC3YUa awzhy3IF8A1QvmJ5kYyE40dvSq3YAZ/l/lmTr8MoYazmL16x/kjnmpbs5Liirw== From: Luca Ceresoli Date: Fri, 20 Jun 2025 17:59:54 +0200 Subject: [PATCH v9 2/3] drm/bridge: get/put the bridge reference in drm_bridge_attach/detach() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250620-drm-bridge-alloc-getput-drm-bridge-c-v9-2-ca53372c9a84@bootlin.com> References: <20250620-drm-bridge-alloc-getput-drm-bridge-c-v9-0-ca53372c9a84@bootlin.com> In-Reply-To: <20250620-drm-bridge-alloc-getput-drm-bridge-c-v9-0-ca53372c9a84@bootlin.com> To: Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter Cc: Dmitry Baryshkov , Anusha Srivatsa , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Hui Pu , Thomas Petazzoni , Luca Ceresoli X-Mailer: b4 0.14.2 X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtddvgdekkedvucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuifetpfffkfdpucggtfgfnhhsuhgsshgtrhhisggvnecuuegrihhlohhuthemuceftddunecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhfffugggtgffkfhgjvfevofesthejredtredtjeenucfhrhhomhepnfhutggrucevvghrvghsohhlihcuoehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeeiieeuvdfftefgueduleehueetgffgjeeitedtteetkeeuueeuueekveevvdeuveenucfkphepvdgrtddvmeeijedtmedvtddvtdemvggrtddumegsvgegudemleehvgejmeefgeefmeeludefvgenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpedvrgdtvdemieejtdemvddtvddtmegvrgdtudemsggvgedumeelhegvjeemfeegfeemledufegvpdhhvghloheplgduledvrdduieekrddujeekrdejhegnpdhmrghilhhfrhhomheplhhutggrrdgtvghrvghsohhlihessghoohhtlhhinhdrtghomhdpnhgspghrtghpthhtohepudekpdhrtghpthhtohepthiiihhmmhgvrhhmrghnnhesshhushgvrdguvgdprhgtphhtthhopehthhhomhgrshdrphgvthgriiiiohhnihessghoohhtlhhinhdrtghomhdprhgtphhtthhopehmrggrrhhtvghnrdhlrghnkhhhohhrshhtsehlihhnuhigrdhin hhtvghlrdgtohhmpdhrtghpthhtohepughrihdquggvvhgvlheslhhishhtshdrfhhrvggvuggvshhkthhophdrohhrghdprhgtphhtthhopefjuhhirdfruhesghgvhhgvrghlthhhtggrrhgvrdgtohhmpdhrtghpthhtohepnfgruhhrvghnthdrphhinhgthhgrrhhtsehiuggvrghsohhnsghorghrugdrtghomhdprhgtphhtthhopehlihhnuhigqdhkvghrnhgvlhesvhhgvghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopegrshhrihhvrghtshesrhgvughhrghtrdgtohhm X-GND-Sasl: luca.ceresoli@bootlin.com drm_bridge_attach() adds the bridge to the encoder chain, so take a reference for that. Vice versa in drm_bridge_detach(). Reviewed-by: Maxime Ripard Signed-off-by: Luca Ceresoli --- Changes in v9: none Changes in v8: none Changes in v7: - in v6 this was part of "drm/bridge: add support for refcounted DRM bridges", now split to a separate patch --- drivers/gpu/drm/drm_bridge.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index fa2b2457b16e145e3ace70c53984937096d310d0..f001bbe95559aabf0aac9f25f89= 250ad4e1ad9c8 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -411,11 +411,17 @@ int drm_bridge_attach(struct drm_encoder *encoder, st= ruct drm_bridge *bridge, if (!encoder || !bridge) return -EINVAL; =20 - if (previous && (!previous->dev || previous->encoder !=3D encoder)) - return -EINVAL; + drm_bridge_get(bridge); =20 - if (bridge->dev) - return -EBUSY; + if (previous && (!previous->dev || previous->encoder !=3D encoder)) { + ret =3D -EINVAL; + goto err_put_bridge; + } + + if (bridge->dev) { + ret =3D -EBUSY; + goto err_put_bridge; + } =20 bridge->dev =3D encoder->dev; bridge->encoder =3D encoder; @@ -464,6 +470,8 @@ int drm_bridge_attach(struct drm_encoder *encoder, stru= ct drm_bridge *bridge, "failed to attach bridge %pOF to encoder %s\n", bridge->of_node, encoder->name); =20 +err_put_bridge: + drm_bridge_put(bridge); return ret; } EXPORT_SYMBOL(drm_bridge_attach); @@ -484,6 +492,7 @@ void drm_bridge_detach(struct drm_bridge *bridge) =20 list_del(&bridge->chain_node); bridge->dev =3D NULL; + drm_bridge_put(bridge); } =20 /** --=20 2.49.0