From patchwork Thu Mar 20 15:42:10 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Ceresoli X-Patchwork-Id: 14024085 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 2890EC35FFF for ; Thu, 20 Mar 2025 15:42:48 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C42AE10E653; Thu, 20 Mar 2025 15:42:44 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="MuoWdizQ"; dkim-atps=neutral Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) by gabe.freedesktop.org (Postfix) with ESMTPS id A0D3110E656 for ; Thu, 20 Mar 2025 15:42:36 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id 00BFB443F7; Thu, 20 Mar 2025 15:42:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1742485355; 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=u5vlr+GowG3k6kvnZqjl6Q+kHm29g1HSl0BeOMepAZM=; b=MuoWdizQB6f+QDaFA8t6AcIoH2fvem96IrOShMTv55PcoFkZOPGMrGoTbUxyjCI2TIWYaS 1RCUaQzgz/O0VhRoGa1dZo1vZvcdIV6b+c+ZujGcd93RNY/xMjo6XjrT3ZNRc2xx9EQkFQ 7r2ZEc0Fy1N2ICKQHXSirVCmf+wRNOWsOmybi12/VfxdveY+8YUsybTnmOMGfTxmXboWTi G9am+cO8qHNSip8TQ9CKuYViGk7tVksMeQob0apCK39En+f3QtpQglERg7dt+KaxE1VlPR VXLNeBcpQ7Al3dF6uKKzNnwaWt8FwEGXGSMJSvmQbwCGrwqDdWm/oZsYmCvO+w== From: Luca Ceresoli Date: Thu, 20 Mar 2025 16:42:10 +0100 Subject: [PATCH v8 1/5] drm/bridge: add devm_drm_bridge_alloc() MIME-Version: 1.0 Message-Id: <20250320-drm-bridge-refcount-v8-1-b3ddaa9f1368@bootlin.com> References: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@bootlin.com> In-Reply-To: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@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 , Marek Vasut , Stefan Agner , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Inki Dae , Jagan Teki , Marek Szyprowski Cc: Thomas Petazzoni , Anusha Srivatsa , Paul Kocialkowski , Dmitry Baryshkov , =?utf-8?q?Herv=C3=A9_Codina?= , Hui Pu , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Luca Ceresoli X-Mailer: b4 0.14.2 X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgddugeekiedtucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuifetpfffkfdpucggtfgfnhhsuhgsshgtrhhisggvnecuuegrihhlohhuthemuceftddunecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhfffugggtgffkfhgjvfevofesthejredtredtjeenucfhrhhomhepnfhutggrucevvghrvghsohhlihcuoehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeeiieeuvdfftefgueduleehueetgffgjeeitedtteetkeeuueeuueekveevvdeuveenucfkphepvdgrtddvmeeijedtmedvtddvtdemvggrtddumegsvgegudemleehvgejmeefgeefmeeludefvgenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpedvrgdtvdemieejtdemvddtvddtmegvrgdtudemsggvgedumeelhegvjeemfeegfeemledufegvpdhhvghloheplgduledvrdduieekrddujeekrdduudekngdpmhgrihhlfhhrohhmpehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopeefuddprhgtphhtthhopehrfhhoshhssehkvghrnhgvlhdrohhrghdprhgtphhtthhopegrnhgurhiivghjrdhhrghjuggrsehinhhtvghlrdgtohhmpdhrtghpthhtohepthiiihhmmhgvrhhmrghnnhesshhushgvrdguvgdprhgtphhtthhopehimhigs ehlihhsthhsrdhlihhnuhigrdguvghvpdhrtghpthhtohepjhgvrhhnvghjrdhskhhrrggsvggtsehgmhgrihhlrdgtohhmpdhrtghpthhtoheplhhutggrrdgtvghrvghsohhlihessghoohhtlhhinhdrtghomhdprhgtphhtthhopefnrghurhgvnhhtrdhpihhntghhrghrthesihguvggrshhonhgsohgrrhgurdgtohhmpdhrtghpthhtohephhgvrhhvvgdrtghoughinhgrsegsohhothhlihhnrdgtohhm 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" Add a macro to allocate and initialize a DRM bridge embedded within a private driver struct. Compared to current practice, which is based on [devm_]kzalloc() allocation followed by open-coded initialization of fields, this allows to have a common and explicit API to allocate and initialize DRM bridges. Besides being useful to consolidate bridge driver code, this is a fundamental step in preparation for adding dynamic lifetime to bridges based on refcount. Reviewed-by: Maxime Ripard Signed-off-by: Luca Ceresoli --- 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 | 22 ++++++++++++++++++++++ include/drm/drm_bridge.h | 17 +++++++++++++++++ 2 files changed, 39 insertions(+) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index ef98e21dc593f38a2d3c67b850032ece38bec5e8..84fa1a1330cbabd309526829fff70971cfed1dcd 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -199,6 +199,28 @@ static DEFINE_MUTEX(bridge_lock); static LIST_HEAD(bridge_list); +void *__devm_drm_bridge_alloc(struct device *dev, size_t size, size_t offset, + const struct drm_bridge_funcs *funcs) +{ + void *container; + struct drm_bridge *bridge; + + if (!funcs) { + dev_warn(dev, "Missing funcs pointer\n"); + return ERR_PTR(-EINVAL); + } + + container = devm_kzalloc(dev, size, GFP_KERNEL); + if (!container) + return ERR_PTR(-ENOMEM); + + bridge = container + offset; + bridge->funcs = funcs; + + return container; +} +EXPORT_SYMBOL(__devm_drm_bridge_alloc); + /** * drm_bridge_add - add the given bridge to the global bridge list * diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index cdad3b78a195aa39776c93e2371217d3d3fb6064..a59277674d5a2937e324d3ce48f934418788053f 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -941,6 +941,23 @@ drm_priv_to_bridge(struct drm_private_obj *priv) return container_of(priv, struct drm_bridge, base); } +void *__devm_drm_bridge_alloc(struct device *dev, size_t size, size_t offset, + const struct drm_bridge_funcs *funcs); + +/** + * devm_drm_bridge_alloc - Allocate and initialize a bridge + * @dev: struct device of the bridge device + * @type: the type of the struct which contains struct &drm_bridge + * @member: the name of the &drm_bridge within @type + * @funcs: callbacks for this bridge + * + * Returns: + * Pointer to new bridge, or ERR_PTR on failure. + */ +#define devm_drm_bridge_alloc(dev, type, member, funcs) \ + ((type *)__devm_drm_bridge_alloc(dev, sizeof(type), \ + offsetof(type, member), funcs)) + void drm_bridge_add(struct drm_bridge *bridge); int devm_drm_bridge_add(struct device *dev, struct drm_bridge *bridge); void drm_bridge_remove(struct drm_bridge *bridge); From patchwork Thu Mar 20 15:42:11 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Ceresoli X-Patchwork-Id: 14024086 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 817BCC28B30 for ; Thu, 20 Mar 2025 15:42:49 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6099810E65A; Thu, 20 Mar 2025 15:42:45 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="kmLmW1is"; dkim-atps=neutral Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) by gabe.freedesktop.org (Postfix) with ESMTPS id B467E10E657 for ; Thu, 20 Mar 2025 15:42:38 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id 41BE644412; Thu, 20 Mar 2025 15:42:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1742485357; 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=76ShvGbKTWCnojDi2WXjYtsq+IEWC3ZZCKont8aYmXs=; b=kmLmW1isJD2fDW3va4maqtq0Zut9KNgM1yAQVqQWKGbx68j0Z6hXG+iOBcgyk9Mhm7GRtF bqZgb/r21RFRD81PLLx6pnfwYoZo9FBFOnc37/0L0+LmD6UxpphiXszqEhqWSC667of06F 98BACERuCZG0m/iK5L7XbU+yJAT0rVK5Bv3I3+KN1SXaAeZO6qywCIprBQTEUxq6VKcCTe C5o88BxwvcRcTVlULTRO4Ghi9TcrYf0rfHFN7+gkuUliS/RSC2h/IDX2KWlNMTlgwUCSaZ akX5ykoHh2IbMwJ6IB86TkpvDmHBRBG0EOPc1XfgAL7KQTngxnNBlm4wvawEgA== From: Luca Ceresoli Date: Thu, 20 Mar 2025 16:42:11 +0100 Subject: [PATCH v8 2/5] drm/bridge: add support for refcounting MIME-Version: 1.0 Message-Id: <20250320-drm-bridge-refcount-v8-2-b3ddaa9f1368@bootlin.com> References: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@bootlin.com> In-Reply-To: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@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 , Marek Vasut , Stefan Agner , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Inki Dae , Jagan Teki , Marek Szyprowski Cc: Thomas Petazzoni , Anusha Srivatsa , Paul Kocialkowski , Dmitry Baryshkov , =?utf-8?q?Herv=C3=A9_Codina?= , Hui Pu , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Luca Ceresoli X-Mailer: b4 0.14.2 X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgddugeekiedtucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuifetpfffkfdpucggtfgfnhhsuhgsshgtrhhisggvnecuuegrihhlohhuthemuceftddunecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhfffugggtgffkfhgjvfevofesthejredtredtjeenucfhrhhomhepnfhutggrucevvghrvghsohhlihcuoehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeeiieeuvdfftefgueduleehueetgffgjeeitedtteetkeeuueeuueekveevvdeuveenucfkphepvdgrtddvmeeijedtmedvtddvtdemvggrtddumegsvgegudemleehvgejmeefgeefmeeludefvgenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpedvrgdtvdemieejtdemvddtvddtmegvrgdtudemsggvgedumeelhegvjeemfeegfeemledufegvpdhhvghloheplgduledvrdduieekrddujeekrdduudekngdpmhgrihhlfhhrohhmpehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopeefuddprhgtphhtthhopehrfhhoshhssehkvghrnhgvlhdrohhrghdprhgtphhtthhopegrnhgurhiivghjrdhhrghjuggrsehinhhtvghlrdgtohhmpdhrtghpthhtohepthiiihhmmhgvrhhmrghnnhesshhushgvrdguvgdprhgtphhtthhopehimhigs ehlihhsthhsrdhlihhnuhigrdguvghvpdhrtghpthhtohepjhgvrhhnvghjrdhskhhrrggsvggtsehgmhgrihhlrdgtohhmpdhrtghpthhtoheplhhutggrrdgtvghrvghsohhlihessghoohhtlhhinhdrtghomhdprhgtphhtthhopefnrghurhgvnhhtrdhpihhntghhrghrthesihguvggrshhonhgsohgrrhgurdgtohhmpdhrtghpthhtohephhgvrhhvvgdrtghoughinhgrsegsohhothhlihhnrdgtohhm 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" DRM bridges are currently considered as a fixed element of a DRM card, and thus their lifetime is assumed to extend for as long as the card exists. New use cases, such as hot-pluggable hardware with video bridges, require DRM bridges to be added to and removed from a DRM card without tearing the card down. This is possible for connectors already (used by DP MST), it is now needed for DRM bridges as well. As a first preliminary step, make bridges reference-counted to allow a struct drm_bridge (along with the private driver structure embedding it) to stay allocated even after the driver has been removed, until the last reference is put. Signed-off-by: Luca Ceresoli Reviewed-by: Maxime Ripard --- Changes in v8: - move back drm_bridge_get/put() to the .c file, make __drm_bridge_free private - move back drm_bridge_put_void() to .c, not used in this series outside of drm_bridge.c - remove drm_bridge_put_and_clear(), not used in this series - minor docs and coding style tweaks Changes in v7: - export drm_bridge_put_void - struct drm_bridge: use container pointer instead of container_offset - remove drm_bridge_is_refcounted() - remove all DRM_DEBUG()s - drm_bridge_get/put: accept NULL pointer and return the bridge pointer to allow pass-through calls - extract to separate patches: - the addition of drm_bridge_alloc - the addition of drm_bridge_get/put() to drm_bridge_add/remove() - the addition of drm_bridge_get/put() to drm_bridge_attach/detach() - fix a typo, slightly improve kerneldoc Changes in v6: - use drm_warn, not WARN_ON (Jani Nikula) - Add devm_drm_bridge_alloc() to replace drm_bridge_init() (similar to drmm_encoder_alloc) - Remove .destroy func: deallocation is done via the struct offset computed by the devm_drm_bridge_alloc() macro - use fixed free callback, as the same callback is used in all cases anyway (remove free_cb, add bool is_refcounted) - add drm_bridge_get/put() to drm_bridge_attach/detach() (add the bridge to a list) - make some DRM_DEBUG() strings more informative This patch was added in v5. --- drivers/gpu/drm/drm_bridge.c | 72 +++++++++++++++++++++++++++++++++++++++++++- include/drm/drm_bridge.h | 19 ++++++++++++ 2 files changed, 90 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 84fa1a1330cbabd309526829fff70971cfed1dcd..2f2ecb73308e601b1a53ec8e7110933cef59b5da 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -199,23 +199,93 @@ static DEFINE_MUTEX(bridge_lock); static LIST_HEAD(bridge_list); +static void __drm_bridge_free(struct kref *kref) +{ + struct drm_bridge *bridge = container_of(kref, struct drm_bridge, refcount); + + kfree(bridge->container); +} + +/** + * drm_bridge_get - Acquire a bridge reference + * @bridge: DRM bridge + * + * This function increments the bridge's refcount. + * + * Returns: + * Pointer to @bridge. + */ +struct drm_bridge *drm_bridge_get(struct drm_bridge *bridge) +{ + if (!bridge) + return bridge; + + kref_get(&bridge->refcount); + + return bridge; +} +EXPORT_SYMBOL(drm_bridge_get); + +/** + * drm_bridge_put - Release a bridge reference + * @bridge: DRM bridge + * + * This function decrements the bridge's reference count and frees the + * object if the reference count drops to zero. + * + * Returns: + * Pointer to @bridge. + */ +struct drm_bridge *drm_bridge_put(struct drm_bridge *bridge) +{ + if (!bridge) + return bridge; + + kref_put(&bridge->refcount, __drm_bridge_free); + + return bridge; +} +EXPORT_SYMBOL(drm_bridge_put); + +/** + * drm_bridge_put_void - wrapper to drm_bridge_put() taking a void pointer + * + * @data: pointer to @struct drm_bridge, cast to a void pointer + * + * Wrapper of drm_bridge_put() to be used when a function taking a void + * pointer is needed, for example as a devm action. + */ +static void drm_bridge_put_void(void *data) +{ + struct drm_bridge *bridge = (struct drm_bridge *)data; + + drm_bridge_put(bridge); +} + void *__devm_drm_bridge_alloc(struct device *dev, size_t size, size_t offset, const struct drm_bridge_funcs *funcs) { void *container; struct drm_bridge *bridge; + int err; if (!funcs) { dev_warn(dev, "Missing funcs pointer\n"); return ERR_PTR(-EINVAL); } - container = devm_kzalloc(dev, size, GFP_KERNEL); + container = kzalloc(size, GFP_KERNEL); if (!container) return ERR_PTR(-ENOMEM); bridge = container + offset; + bridge->container = container; bridge->funcs = funcs; + kref_init(&bridge->refcount); + + err = devm_add_action_or_reset(dev, drm_bridge_put_void, bridge); + if (err) + return ERR_PTR(err); return container; } diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index a59277674d5a2937e324d3ce48f934418788053f..076f40c17dd86b224bbe6517b71f1aa6c24bfbd7 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -840,6 +840,18 @@ struct drm_bridge { const struct drm_bridge_timings *timings; /** @funcs: control functions */ const struct drm_bridge_funcs *funcs; + + /** + * @container: Pointer to the private driver struct embedding this + * @struct drm_bridge. + */ + void *container; + + /** + * @refcount: reference count of users referencing this bridge. + */ + struct kref refcount; + /** @driver_private: pointer to the bridge driver's internal context */ void *driver_private; /** @ops: bitmask of operations supported by the bridge */ @@ -941,6 +953,9 @@ drm_priv_to_bridge(struct drm_private_obj *priv) return container_of(priv, struct drm_bridge, base); } +struct drm_bridge *drm_bridge_get(struct drm_bridge *bridge); +struct drm_bridge *drm_bridge_put(struct drm_bridge *bridge); + void *__devm_drm_bridge_alloc(struct device *dev, size_t size, size_t offset, const struct drm_bridge_funcs *funcs); @@ -951,6 +966,10 @@ void *__devm_drm_bridge_alloc(struct device *dev, size_t size, size_t offset, * @member: the name of the &drm_bridge within @type * @funcs: callbacks for this bridge * + * The reference count of the returned bridge is initialized to 1. This + * reference will be automatically dropped via devm (by calling + * drm_bridge_put()) when @dev is removed. + * * Returns: * Pointer to new bridge, or ERR_PTR on failure. */ From patchwork Thu Mar 20 15:42:12 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Ceresoli X-Patchwork-Id: 14024088 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 C84C6C28B30 for ; Thu, 20 Mar 2025 15:42:55 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 402AC10E64D; Thu, 20 Mar 2025 15:42:55 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="BOwk98/T"; dkim-atps=neutral Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) by gabe.freedesktop.org (Postfix) with ESMTPS id CCA8510E652 for ; Thu, 20 Mar 2025 15:42:40 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id 7E2B444417; Thu, 20 Mar 2025 15:42:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1742485359; 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=jyBNDLsArbdd7WHk93rkhCfp9ThfO49YHtAhELFf8JY=; b=BOwk98/TpGkOxzJx4oiUhpGhy8r0YMvaGQJYOINSzpbd20HMenb3xP12VjS//hVhI72Iam t9Dpvqpn8S9iRISG6Tg5phGO/QXvlbJB2vfZGxLCXG957uZvZcbWhedktWUQnkjPAoXxIs HkQAv1VRQ7IgMzM3YKaxo4NQO0jqfvwhuwPuz9VTzVxZXedGBuvGeTx06uh/oLs4vzRkd5 JxTYtaW0T0J4NlVjtMed+UKicoT37q+vyPsn0wG71dm+a7wyCghXMAbpy1ZMeukJ1pdC8t Qkzr8akHHSnnpISG93yuGxJDUJ54W0Ipu4fHEWwA6kW7Ab289RadMxvwAhSdfQ== From: Luca Ceresoli Date: Thu, 20 Mar 2025 16:42:12 +0100 Subject: [PATCH v8 3/5] drm/bridge: deprecate old-style bridge allocation MIME-Version: 1.0 Message-Id: <20250320-drm-bridge-refcount-v8-3-b3ddaa9f1368@bootlin.com> References: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@bootlin.com> In-Reply-To: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@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 , Marek Vasut , Stefan Agner , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Inki Dae , Jagan Teki , Marek Szyprowski Cc: Thomas Petazzoni , Anusha Srivatsa , Paul Kocialkowski , Dmitry Baryshkov , =?utf-8?q?Herv=C3=A9_Codina?= , Hui Pu , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Luca Ceresoli X-Mailer: b4 0.14.2 X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgddugeekiedtucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuifetpfffkfdpucggtfgfnhhsuhgsshgtrhhisggvnecuuegrihhlohhuthemuceftddunecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhfffugggtgffkfhgjvfevofesthejredtredtjeenucfhrhhomhepnfhutggrucevvghrvghsohhlihcuoehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeeiieeuvdfftefgueduleehueetgffgjeeitedtteetkeeuueeuueekveevvdeuveenucfkphepvdgrtddvmeeijedtmedvtddvtdemvggrtddumegsvgegudemleehvgejmeefgeefmeeludefvgenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpedvrgdtvdemieejtdemvddtvddtmegvrgdtudemsggvgedumeelhegvjeemfeegfeemledufegvpdhhvghloheplgduledvrdduieekrddujeekrdduudekngdpmhgrihhlfhhrohhmpehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopeefuddprhgtphhtthhopehrfhhoshhssehkvghrnhgvlhdrohhrghdprhgtphhtthhopegrnhgurhiivghjrdhhrghjuggrsehinhhtvghlrdgtohhmpdhrtghpthhtohepthiiihhmmhgvrhhmrghnnhesshhushgvrdguvgdprhgtphhtthhopehimhigs ehlihhsthhsrdhlihhnuhigrdguvghvpdhrtghpthhtohepjhgvrhhnvghjrdhskhhrrggsvggtsehgmhgrihhlrdgtohhmpdhrtghpthhtoheplhhutggrrdgtvghrvghsohhlihessghoohhtlhhinhdrtghomhdprhgtphhtthhopefnrghurhgvnhhtrdhpihhntghhrghrthesihguvggrshhonhgsohgrrhgurdgtohhmpdhrtghpthhtohephhgvrhhvvgdrtghoughinhgrsegsohhothhlihhnrdgtohhm 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" All DRM bridges are now supposed to be allocated using devm_drm_bridge_alloc(), which is cleaner and necessary to support refcounting. Deprecate old school allocation using kzalloc and derivatives. In the absence of a drm_bridge_init() or such initialization function, document the deprecation on the first DRM bridge core function that is called after allocation, i.e. drm_bridge_add(). Suggested-by: Maxime Ripard Signed-off-by: Luca Ceresoli --- This patch was added in v8. --- drivers/gpu/drm/drm_bridge.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 2f2ecb73308e601b1a53ec8e7110933cef59b5da..17659b1cbdeae04e10b76f2aabc8ebba65c4f6e1 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -295,6 +295,10 @@ EXPORT_SYMBOL(__devm_drm_bridge_alloc); * drm_bridge_add - add the given bridge to the global bridge list * * @bridge: bridge control structure + * + * The bridge to be added must have been allocated by + * devm_drm_bridge_alloc(). Old-style allocation by kzalloc(), + * devm_kzalloc() and similar is deprecated. */ void drm_bridge_add(struct drm_bridge *bridge) { From patchwork Thu Mar 20 15:42:13 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Ceresoli X-Patchwork-Id: 14024084 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 75160C36001 for ; Thu, 20 Mar 2025 15:42:46 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 467BA10E652; Thu, 20 Mar 2025 15:42:44 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="l8hW87W1"; dkim-atps=neutral Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1075E10E653 for ; Thu, 20 Mar 2025 15:42:42 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id B5BD144422; Thu, 20 Mar 2025 15:42:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1742485361; 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=xu+uoSfSOhkoTShUNDlJziaFGObfGRc5heue1JT/SkA=; b=l8hW87W1U80LDg6/V28vPyf0zY+gWD7Ef2JWgTmvbX9ueX4P/4BKn3ggyru4OjfnXHUyk1 nxJIu05MFBofXfTFVi3dedj6ZMrwdqfe5H5H5nx3CQWsrnotsRZvHoMsQhmABKxgrdRc2H LcK59kJpDObXEvaiH/b4bchbxy/oa3ECxPkf0reTMaXJaAg83YK7iyGzm723aTGo/Gg311 LKqi70Km3XZlmLvym5YZ7DuY0c/JWfPapGh5SvUo9J+BbFx5eBxqibs8/OxulD/U/VJyIJ YqTuyx9VS/+qjTx8IofKcgf5zWVqVVnMYfVL3t8FQvYFWZ8Wb8CkR0s7xQYPhw== From: Luca Ceresoli Date: Thu, 20 Mar 2025 16:42:13 +0100 Subject: [PATCH v8 4/5] drm/bridge: ti-sn65dsi83: use dynamic lifetime management MIME-Version: 1.0 Message-Id: <20250320-drm-bridge-refcount-v8-4-b3ddaa9f1368@bootlin.com> References: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@bootlin.com> In-Reply-To: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@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 , Marek Vasut , Stefan Agner , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Inki Dae , Jagan Teki , Marek Szyprowski Cc: Thomas Petazzoni , Anusha Srivatsa , Paul Kocialkowski , Dmitry Baryshkov , =?utf-8?q?Herv=C3=A9_Codina?= , Hui Pu , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Luca Ceresoli X-Mailer: b4 0.14.2 X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgddugeekiedtucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuifetpfffkfdpucggtfgfnhhsuhgsshgtrhhisggvnecuuegrihhlohhuthemuceftddunecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhfffugggtgffkfhgjvfevofesthejredtredtjeenucfhrhhomhepnfhutggrucevvghrvghsohhlihcuoehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeeiieeuvdfftefgueduleehueetgffgjeeitedtteetkeeuueeuueekveevvdeuveenucfkphepvdgrtddvmeeijedtmedvtddvtdemvggrtddumegsvgegudemleehvgejmeefgeefmeeludefvgenucevlhhushhtvghrufhiiigvpeefnecurfgrrhgrmhepihhnvghtpedvrgdtvdemieejtdemvddtvddtmegvrgdtudemsggvgedumeelhegvjeemfeegfeemledufegvpdhhvghloheplgduledvrdduieekrddujeekrdduudekngdpmhgrihhlfhhrohhmpehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopeefuddprhgtphhtthhopehrfhhoshhssehkvghrnhgvlhdrohhrghdprhgtphhtthhopegrnhgurhiivghjrdhhrghjuggrsehinhhtvghlrdgtohhmpdhrtghpthhtohepthiiihhmmhgvrhhmrghnnhesshhushgvrdguvgdprhgtphhtthhopehimhigs ehlihhsthhsrdhlihhnuhigrdguvghvpdhrtghpthhtohepjhgvrhhnvghjrdhskhhrrggsvggtsehgmhgrihhlrdgtohhmpdhrtghpthhtoheplhhutggrrdgtvghrvghsohhlihessghoohhtlhhinhdrtghomhdprhgtphhtthhopefnrghurhgvnhhtrdhpihhntghhrghrthesihguvggrshhonhgsohgrrhgurdgtohhmpdhrtghpthhtohephhgvrhhvvgdrtghoughinhgrsegsohhothhlihhnrdgtohhm 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" Allow this bridge to be removable without dangling pointers and use-after-free, together with proper use of drm_bridge_get() and _put() by consumers. Reviewed-by: Maxime Ripard Signed-off-by: Luca Ceresoli --- Changes in v8: none Changes in v7: none Changed in v6: - Update to use devm_drm_bridge_alloc(), remove .destroy This patch was added in v5. --- drivers/gpu/drm/bridge/ti-sn65dsi83.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi83.c b/drivers/gpu/drm/bridge/ti-sn65dsi83.c index 6e0ba427c2582c33f7b95634a18dcda9ac28267f..4efb62376e196d8bb5e9f58867e5c0e1624391db 100644 --- a/drivers/gpu/drm/bridge/ti-sn65dsi83.c +++ b/drivers/gpu/drm/bridge/ti-sn65dsi83.c @@ -947,9 +947,9 @@ static int sn65dsi83_probe(struct i2c_client *client) struct sn65dsi83 *ctx; int ret; - ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL); - if (!ctx) - return -ENOMEM; + ctx = devm_drm_bridge_alloc(dev, struct sn65dsi83, bridge, &sn65dsi83_funcs); + if (IS_ERR(ctx)) + return PTR_ERR(ctx); ctx->dev = dev; INIT_WORK(&ctx->reset_work, sn65dsi83_reset_work); @@ -989,7 +989,6 @@ static int sn65dsi83_probe(struct i2c_client *client) dev_set_drvdata(dev, ctx); i2c_set_clientdata(client, ctx); - ctx->bridge.funcs = &sn65dsi83_funcs; ctx->bridge.of_node = dev->of_node; ctx->bridge.pre_enable_prev_first = true; ctx->bridge.type = DRM_MODE_CONNECTOR_LVDS; From patchwork Thu Mar 20 15:42:14 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Ceresoli X-Patchwork-Id: 14024087 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 BFD7EC35FFF for ; Thu, 20 Mar 2025 15:42:52 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 233FF10E65B; Thu, 20 Mar 2025 15:42:52 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=bootlin.com header.i=@bootlin.com header.b="HvEc1FLO"; dkim-atps=neutral Received: from relay8-d.mail.gandi.net (relay8-d.mail.gandi.net [217.70.183.201]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3ECD610E657 for ; Thu, 20 Mar 2025 15:42:45 +0000 (UTC) Received: by mail.gandi.net (Postfix) with ESMTPSA id EEE8444408; Thu, 20 Mar 2025 15:42:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1742485364; 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=XgB3E9/XVLuIu4T8MuTOjtqbhqCUgDiA94vVvHuz8zk=; b=HvEc1FLOCYSH103JmeD8Ac+x9C0qJ0Yb8aCnQUAeURjilBPqBtie+pEAoS3bBCZ1mMTRzO w+13OS9sCiWwoSsG4oQyPRAWozN+S0y5TTrnLN483RDVVK3dg4ttRLLEGBGH2Qa/11fzP0 8zipHiAyUGjNh3G9uDEHZJqYx6tcS4+Zk0ymioLVp0h2VmI0td4ocYdnre332hfOQznbj4 yWaX5AYsC4VtWUiTeSeSQZAYSMN+5KzjBk0lg3nvvUiRRXgYdx0gIRF3NUupoEESpC9jjO gYD7P8qZob3Tf2zlkopohKCm/FfM4FQ5CyDpfb2F/DPOvaKovj04kko/z3htHw== From: Luca Ceresoli Date: Thu, 20 Mar 2025 16:42:14 +0100 Subject: [PATCH v8 5/5] drm/bridge: samsung-dsim: use dynamic lifetime management MIME-Version: 1.0 Message-Id: <20250320-drm-bridge-refcount-v8-5-b3ddaa9f1368@bootlin.com> References: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@bootlin.com> In-Reply-To: <20250320-drm-bridge-refcount-v8-0-b3ddaa9f1368@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 , Marek Vasut , Stefan Agner , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Inki Dae , Jagan Teki , Marek Szyprowski Cc: Thomas Petazzoni , Anusha Srivatsa , Paul Kocialkowski , Dmitry Baryshkov , =?utf-8?q?Herv=C3=A9_Codina?= , Hui Pu , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Luca Ceresoli X-Mailer: b4 0.14.2 X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgddugeekiedtucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuifetpfffkfdpucggtfgfnhhsuhgsshgtrhhisggvnecuuegrihhlohhuthemuceftddunecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpefhfffugggtgffkfhgjvfevofesthejredtredtjeenucfhrhhomhepnfhutggrucevvghrvghsohhlihcuoehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeeiieeuvdfftefgueduleehueetgffgjeeitedtteetkeeuueeuueekveevvdeuveenucfkphepvdgrtddvmeeijedtmedvtddvtdemvggrtddumegsvgegudemleehvgejmeefgeefmeeludefvgenucevlhhushhtvghrufhiiigvpeefnecurfgrrhgrmhepihhnvghtpedvrgdtvdemieejtdemvddtvddtmegvrgdtudemsggvgedumeelhegvjeemfeegfeemledufegvpdhhvghloheplgduledvrdduieekrddujeekrdduudekngdpmhgrihhlfhhrohhmpehluhgtrgdrtggvrhgvshholhhisegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopeefuddprhgtphhtthhopehrfhhoshhssehkvghrnhgvlhdrohhrghdprhgtphhtthhopegrnhgurhiivghjrdhhrghjuggrsehinhhtvghlrdgtohhmpdhrtghpthhtohepthiiihhmmhgvrhhmrghnnhesshhushgvrdguvgdprhgtphhtthhopehimhigs ehlihhsthhsrdhlihhnuhigrdguvghvpdhrtghpthhtohepjhgvrhhnvghjrdhskhhrrggsvggtsehgmhgrihhlrdgtohhmpdhrtghpthhtoheplhhutggrrdgtvghrvghsohhlihessghoohhtlhhinhdrtghomhdprhgtphhtthhopefnrghurhgvnhhtrdhpihhntghhrghrthesihguvggrshhonhgsohgrrhgurdgtohhmpdhrtghpthhtohephhgvrhhvvgdrtghoughinhgrsegsohhothhlihhnrdgtohhm 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" Allow this bridge to be removable without dangling pointers and use-after-free, together with proper use of drm_bridge_get() and _put() by consumers. Reviewed-by: Maxime Ripard Signed-off-by: Luca Ceresoli --- Changes in v8: none This patch was added in v7. --- drivers/gpu/drm/bridge/samsung-dsim.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c index 55ac6bd5da08c037aa7974df679d51e72bc54faf..0014c497e3fe7d8349a119dbdda30d65d816cccf 100644 --- a/drivers/gpu/drm/bridge/samsung-dsim.c +++ b/drivers/gpu/drm/bridge/samsung-dsim.c @@ -1936,9 +1936,9 @@ int samsung_dsim_probe(struct platform_device *pdev) struct samsung_dsim *dsi; int ret, i; - dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL); - if (!dsi) - return -ENOMEM; + dsi = devm_drm_bridge_alloc(dev, struct samsung_dsim, bridge, &samsung_dsim_bridge_funcs); + if (IS_ERR(dsi)) + return PTR_ERR(dsi); init_completion(&dsi->completed); spin_lock_init(&dsi->transfer_lock); @@ -2008,7 +2008,6 @@ int samsung_dsim_probe(struct platform_device *pdev) pm_runtime_enable(dev); - dsi->bridge.funcs = &samsung_dsim_bridge_funcs; dsi->bridge.of_node = dev->of_node; dsi->bridge.type = DRM_MODE_CONNECTOR_DSI;