{"id":21739,"url":"https://patchwork.libcamera.org/api/1.1/patches/21739/?format=json","web_url":"https://patchwork.libcamera.org/patch/21739/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/1.1/projects/1/?format=json","name":"libcamera","link_name":"libcamera","list_id":"libcamera_core","list_email":"libcamera-devel@lists.libcamera.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20241022145321.25923-4-jacopo.mondi@ideasonboard.com>","date":"2024-10-22T14:53:15","name":"[3/3] libcamera: camera_sensor: Sort factories by priority","commit_ref":null,"pull_url":null,"state":"accepted","archived":false,"hash":"d6245f1484911fbe2395c77e1274866939444c1a","submitter":{"id":143,"url":"https://patchwork.libcamera.org/api/1.1/people/143/?format=json","name":"Jacopo Mondi","email":"jacopo.mondi@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/21739/mbox/","series":[{"id":4736,"url":"https://patchwork.libcamera.org/api/1.1/series/4736/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=4736","date":"2024-10-22T14:53:12","name":"Introduce CameraSensorFactory","version":1,"mbox":"https://patchwork.libcamera.org/series/4736/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/21739/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/21739/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 5D734C32C1\n\tfor ;\n\tTue, 22 Oct 2024 14:53:39 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 8C7CF65398;\n\tTue, 22 Oct 2024 16:53:38 +0200 (CEST)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 01DF865393\n\tfor ;\n\tTue, 22 Oct 2024 16:53:31 +0200 (CEST)","from ideasonboard.com (93-61-96-190.ip145.fastwebnet.it\n\t[93.61.96.190])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 3EF74A47;\n\tTue, 22 Oct 2024 16:51:44 +0200 (CEST)"],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"pqwbVqoM\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1729608704;\n\tbh=FQ7fZ9HQW6gfWzuHo8KMLLnos0GfE8huRu26C/Wl4lo=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=pqwbVqoMyplU4dxM8ZYEc5kM5eFE3a/KMK25JnKFSi7IhmFkpKCg44KW0O3xZ0ykV\n\tYHKejtUIAXR5YyYbmeLTEYKim3FPbMXFFGcO/1GABWXQn3wM3E9+bYZz3keyze5kyU\n\t7CVjXsNwRjRZV6PjOQDRTBwmnZ0MhloLhJeJhlJ0=","From":"Jacopo Mondi ","To":"libcamera-devel@lists.libcamera.org","Cc":"Jacopo Mondi ,\n\tLaurent Pinchart ,\n\tStefan Klug ","Subject":"[PATCH 3/3] libcamera: camera_sensor: Sort factories by priority","Date":"Tue, 22 Oct 2024 16:53:15 +0200","Message-ID":"<20241022145321.25923-4-jacopo.mondi@ideasonboard.com>","X-Mailer":"git-send-email 2.47.0","In-Reply-To":"<20241022145321.25923-1-jacopo.mondi@ideasonboard.com>","References":"<20241022145321.25923-1-jacopo.mondi@ideasonboard.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "},"content":"From: Laurent Pinchart \n\nIn order to support a default implementation for camera sensors when no\nbetter implementation matches, libcamera needs to try \"specialized\"\nimplementations first and pick the default last. Make this possible by\nadding a priority value for factories. Newly registered factories are\ninserted in the factories list sorted by descending priority, and the\ndefault factory uses a negative priority to be inserted as the last\nelement.\n\nThis mechanism may be a bit overkill in the sense that there is no\nexpected use cases for priorities other than trying the default last,\nbut the implementation is simple and easy to understand.\n\nSigned-off-by: Laurent Pinchart \nReviewed-by: Stefan Klug \nReviewed-by: Jacopo Mondi \nSigned-off-by: Jacopo Mondi \n---\n include/libcamera/internal/camera_sensor.h | 12 ++++---\n src/libcamera/sensor/camera_sensor.cpp | 35 ++++++++++++++++---\n src/libcamera/sensor/camera_sensor_legacy.cpp | 2 +-\n 3 files changed, 39 insertions(+), 10 deletions(-)","diff":"diff --git a/include/libcamera/internal/camera_sensor.h b/include/libcamera/internal/camera_sensor.h\nindex 7713aea02fa2..8aafd82e6547 100644\n--- a/include/libcamera/internal/camera_sensor.h\n+++ b/include/libcamera/internal/camera_sensor.h\n@@ -78,12 +78,13 @@ public:\n class CameraSensorFactoryBase\n {\n public:\n-\tCameraSensorFactoryBase(const char *name);\n+\tCameraSensorFactoryBase(const char *name, int priority);\n \tvirtual ~CameraSensorFactoryBase() = default;\n \n \tstatic std::unique_ptr create(MediaEntity *entity);\n \n \tconst std::string &name() const { return name_; }\n+\tint priority() const { return priority_; }\n \n private:\n \tLIBCAMERA_DISABLE_COPY_AND_MOVE(CameraSensorFactoryBase)\n@@ -96,14 +97,15 @@ private:\n \tmatch(MediaEntity *entity) const = 0;\n \n \tstd::string name_;\n+\tint priority_;\n };\n \n template\n class CameraSensorFactory final : public CameraSensorFactoryBase\n {\n public:\n-\tCameraSensorFactory(const char *name)\n-\t\t: CameraSensorFactoryBase(name)\n+\tCameraSensorFactory(const char *name, int priority)\n+\t\t: CameraSensorFactoryBase(name, priority)\n \t{\n \t}\n \n@@ -115,7 +117,7 @@ private:\n \t}\n };\n \n-#define REGISTER_CAMERA_SENSOR(sensor) \\\n-static CameraSensorFactory global_##sensor##Factory{ #sensor };\n+#define REGISTER_CAMERA_SENSOR(sensor, priority) \\\n+static CameraSensorFactory global_##sensor##Factory{ #sensor, priority };\n \n } /* namespace libcamera */\ndiff --git a/src/libcamera/sensor/camera_sensor.cpp b/src/libcamera/sensor/camera_sensor.cpp\nindex 951ebd2cc39f..54cf98b203fd 100644\n--- a/src/libcamera/sensor/camera_sensor.cpp\n+++ b/src/libcamera/sensor/camera_sensor.cpp\n@@ -349,12 +349,13 @@ CameraSensor::~CameraSensor() = default;\n /**\n * \\brief Construct a camera sensor factory base\n * \\param[in] name The camera sensor factory name\n+ * \\param[in] priority Priority order for factory selection\n *\n * Creating an instance of the factory base registers it with the global list of\n * factories, accessible through the factories() function.\n */\n-CameraSensorFactoryBase::CameraSensorFactoryBase(const char *name)\n-\t: name_(name)\n+CameraSensorFactoryBase::CameraSensorFactoryBase(const char *name, int priority)\n+\t: name_(name), priority_(priority)\n {\n \tregisterFactory(this);\n }\n@@ -363,6 +364,12 @@ CameraSensorFactoryBase::CameraSensorFactoryBase(const char *name)\n * \\brief Create an instance of the CameraSensor corresponding to a media entity\n * \\param[in] entity The media entity on the source end of the sensor\n *\n+ * When multiple factories match the same \\a entity, this function selects the\n+ * matching factory with the highest priority as specified to the\n+ * REGISTER_CAMERA_SENSOR() macro at factory registration time. If multiple\n+ * matching factories have the same highest priority value, which factory gets\n+ * selected is undefined and may vary between runs.\n+ *\n * \\return A unique pointer to a new instance of the CameraSensor subclass\n * matching the entity, or a null pointer if no such factory exists\n */\n@@ -399,8 +406,17 @@ std::unique_ptr CameraSensorFactoryBase::create(MediaEntity *entit\n * \\return The name of the factory\n */\n \n+/**\n+ * \\fn CameraSensorFactoryBase::priority()\n+ * \\brief Retrieve the priority value for the factory\n+ * \\return The priority value for the factory\n+ */\n+\n /**\n * \\brief Retrieve the list of all camera sensor factories\n+ *\n+ * The factories are sorted in decreasing priority order.\n+ *\n * \\return The list of camera sensor factories\n */\n std::vector &CameraSensorFactoryBase::factories()\n@@ -423,7 +439,12 @@ void CameraSensorFactoryBase::registerFactory(CameraSensorFactoryBase *factory)\n \tstd::vector &factories =\n \t\tCameraSensorFactoryBase::factories();\n \n-\tfactories.push_back(factory);\n+\tauto pos = std::upper_bound(factories.begin(), factories.end(), factory,\n+\t\t\t\t [](const CameraSensorFactoryBase *value,\n+\t\t\t\t const CameraSensorFactoryBase *elem) {\n+\t\t\t\t\t return value->priority() > elem->priority();\n+\t\t\t\t });\n+\tfactories.insert(pos, factory);\n }\n \n /**\n@@ -449,9 +470,10 @@ void CameraSensorFactoryBase::registerFactory(CameraSensorFactoryBase *factory)\n */\n \n /**\n- * \\def REGISTER_CAMERA_SENSOR(sensor)\n+ * \\def REGISTER_CAMERA_SENSOR(sensor, priority)\n * \\brief Register a camera sensor type to the sensor factory\n * \\param[in] sensor Class name of the CameraSensor derived class to register\n+ * \\param[in] priority Priority order for factory selection\n *\n * Register a CameraSensor subclass with the factory and make it available to\n * try and match sensors. The subclass needs to implement a static match\n@@ -469,6 +491,11 @@ void CameraSensorFactoryBase::registerFactory(CameraSensorFactoryBase *factory)\n * creation succeeded ;\n * - A non-zero error code if the entity matched and the creation failed ; or\n * - A zero error code if the entity didn't match.\n+ *\n+ * When multiple factories can support the same MediaEntity (as in the match()\n+ * function of multiple factories returning true for the same entity), the \\a\n+ * priority argument selects which factory will be used. See\n+ * CameraSensorFactoryBase::create() for more information.\n */\n \n } /* namespace libcamera */\ndiff --git a/src/libcamera/sensor/camera_sensor_legacy.cpp b/src/libcamera/sensor/camera_sensor_legacy.cpp\nindex 68c945331044..a9b15c038251 100644\n--- a/src/libcamera/sensor/camera_sensor_legacy.cpp\n+++ b/src/libcamera/sensor/camera_sensor_legacy.cpp\n@@ -1010,6 +1010,6 @@ std::string CameraSensorLegacy::logPrefix() const\n \treturn \"'\" + entity_->name() + \"'\";\n }\n \n-REGISTER_CAMERA_SENSOR(CameraSensorLegacy)\n+REGISTER_CAMERA_SENSOR(CameraSensorLegacy, -100)\n \n } /* namespace libcamera */\n","prefixes":["3/3"]}