{"id":496,"url":"https://patchwork.libcamera.org/api/patches/496/?format=json","web_url":"https://patchwork.libcamera.org/patch/496/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/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":"<20190203110102.5663-10-kieran.bingham@ideasonboard.com>","date":"2019-02-03T11:01:00","name":"[libcamera-devel,09/11] libcamera: v4l2_device: Add event driven buffer passing","commit_ref":null,"pull_url":null,"state":"superseded","archived":false,"hash":"9fb2d9cb2f3541f8e8388c57264694a1567510e0","submitter":{"id":4,"url":"https://patchwork.libcamera.org/api/people/4/?format=json","name":"Kieran Bingham","email":"kieran.bingham@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/496/mbox/","series":[{"id":165,"url":"https://patchwork.libcamera.org/api/series/165/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=165","date":"2019-02-03T11:00:51","name":"libcamera: V4L2 Streams","version":1,"mbox":"https://patchwork.libcamera.org/series/165/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/496/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/496/checks/","tags":{},"headers":{"Return-Path":"","Received":["from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id CD40F60DB8\n\tfor ;\n\tSun, 3 Feb 2019 12:01:08 +0100 (CET)","from localhost.localdomain\n\t(218.182-78-194.adsl-static.isp.belgacom.be [194.78.182.218])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 7B524D4B;\n\tSun, 3 Feb 2019 12:01:08 +0100 (CET)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1549191668;\n\tbh=Cmht+l0P+IHzGRpfCwRuAbBlWTJUaMyLBGZrKGZuKPs=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=LKxXvCbw/OgrFSvbVATRlSaLoTe87uf1BcBn3V90D09g/gexrDM06bdUzR2D7Fjv2\n\tacO48N9nth93uSFqNiStcLft/Z8hV7zwGq4J0ycEhdL9Fn0gcZBF18q5pugsL4qNrf\n\t/Rno+u7p0Ndb/0KHuTWryYoFAVM0sjsTsvPKdsAQ=","From":"Kieran Bingham ","To":"LibCamera Devel ","Date":"Sun, 3 Feb 2019 12:01:00 +0100","Message-Id":"<20190203110102.5663-10-kieran.bingham@ideasonboard.com>","X-Mailer":"git-send-email 2.19.1","In-Reply-To":"<20190203110102.5663-1-kieran.bingham@ideasonboard.com>","References":"<20190203110102.5663-1-kieran.bingham@ideasonboard.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","Subject":"[libcamera-devel] [PATCH 09/11] libcamera: v4l2_device: Add event\n\tdriven buffer passing","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.23","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","X-List-Received-Date":"Sun, 03 Feb 2019 11:01:10 -0000"},"content":"Register an EventNotifier on our device file descriptor to be notified of\nEventNotifier::Read events. These signal that a buffer is ready for dequeing\non the V4L2Device.\n\nA Buffer is dequeued, and passed through the bufferReady Signal.\n\nSigned-off-by: Kieran Bingham \n---\n src/libcamera/include/v4l2_device.h | 7 ++++++\n src/libcamera/v4l2_device.cpp | 39 +++++++++++++++++++++++++++--\n 2 files changed, 44 insertions(+), 2 deletions(-)","diff":"diff --git a/src/libcamera/include/v4l2_device.h b/src/libcamera/include/v4l2_device.h\nindex d3dad355be58..fbbddad68082 100644\n--- a/src/libcamera/include/v4l2_device.h\n+++ b/src/libcamera/include/v4l2_device.h\n@@ -13,6 +13,7 @@\n #include \n \n #include \n+#include \n \n namespace libcamera {\n \n@@ -107,6 +108,8 @@ public:\n \tint streamOn();\n \tint streamOff();\n \n+\tSignal bufferReady;\n+\n private:\n \tint getFormatSingleplane(V4L2DeviceFormat *fmt);\n \tint setFormatSingleplane(V4L2DeviceFormat *fmt);\n@@ -118,6 +121,8 @@ private:\n \tint exportBuffer(Buffer *buffer);\n \tint exportBuffers(BufferPool *pool);\n \n+\tvoid bufferAvailable(EventNotifier *notifier);\n+\n \tstd::string deviceNode_;\n \tint fd_;\n \tV4L2Capability caps_;\n@@ -126,6 +131,8 @@ private:\n \tenum v4l2_memory memoryType_;\n \n \tBufferPool *bufferPool_;\n+\n+\tEventNotifier *fdEvent_;\n };\n \n } /* namespace libcamera */\ndiff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp\nindex 1fd289137b36..630b43532c3e 100644\n--- a/src/libcamera/v4l2_device.cpp\n+++ b/src/libcamera/v4l2_device.cpp\n@@ -13,6 +13,7 @@\n #include \n \n #include \n+#include \n \n #include \"log.h\"\n #include \"media_object.h\"\n@@ -190,7 +191,8 @@ V4L2Buffer::V4L2Buffer(struct v4l2_buffer &vb)\n * \\param deviceNode The file-system path to the video device node\n */\n V4L2Device::V4L2Device(const std::string &deviceNode)\n-\t: deviceNode_(deviceNode), fd_(-1), bufferPool_(nullptr)\n+\t: deviceNode_(deviceNode), fd_(-1), bufferPool_(nullptr),\n+\t fdEvent_(nullptr)\n {\n \t/*\n \t * We default to an MMAP based CAPTURE device, however this will be\n@@ -674,6 +676,28 @@ Buffer *V4L2Device::dequeueBuffer()\n \treturn bufferPool_->buffers()[buf.index];\n }\n \n+/**\n+ * \\brief Slot to handle completed buffer events from the V4L2 device\n+ *\n+ * When this Slot is called, a Buffer has become available from the device, and\n+ * will be emitted through the bufferReady Signal.\n+ *\n+ * For Capture devices the Buffer will be contain valid data.\n+ * For Output devices the Buffer can be considered empty.\n+ */\n+void V4L2Device::bufferAvailable(EventNotifier *notifier)\n+{\n+\tBuffer *buffer;\n+\n+\tLOG(V4L2, Debug) << \"A buffer is available\";\n+\n+\tbuffer = dequeueBuffer();\n+\n+\tbufferReady.emit(buffer);\n+\n+\tqueueBuffer(buffer);\n+}\n+\n /**\n * \\brief Request that the V4L2Device commences streaming\n *\n@@ -702,13 +726,17 @@ int V4L2Device::streamOn()\n \t\treturn ret;\n \t}\n \n+\tfdEvent_ = new EventNotifier(fd_, EventNotifier::Read);\n+\tfdEvent_->activated.connect(this, &V4L2Device::bufferAvailable);\n+\n \treturn 0;\n }\n \n /**\n * \\brief Request that the V4L2Device stops streaming\n *\n- * Asks the device to halt any current streaming operations.\n+ * Asks the device to halt any current streaming operations and remove the event\n+ * notifier registered against the device file descriptor.\n *\n * \\return 0 if the operation completes or a negative error number otherwise\n */\n@@ -723,7 +751,14 @@ int V4L2Device::streamOff()\n \t\treturn ret;\n \t}\n \n+\tdelete fdEvent_;\n+\n \treturn 0;\n }\n \n+/**\n+ * \\var V4L2Device::bufferReady\n+ * \\brief A Signal handler which emits completed buffers.\n+ */\n+\n } /* namespace libcamera */\n","prefixes":["libcamera-devel","09/11"]}