{"id":2208,"url":"https://patchwork.libcamera.org/api/patches/2208/?format=json","web_url":"https://patchwork.libcamera.org/patch/2208/","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":"<20191022160110.19419-1-kieran.bingham@ideasonboard.com>","date":"2019-10-22T16:01:10","name":"[libcamera-devel,RFC] libcamera: v4l2_videodevice: Track streaming state","commit_ref":null,"pull_url":null,"state":"superseded","archived":false,"hash":"8d32cc755a0e6851334857cd027699dd923dcadc","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/2208/mbox/","series":[{"id":541,"url":"https://patchwork.libcamera.org/api/series/541/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=541","date":"2019-10-22T16:01:10","name":"[libcamera-devel,RFC] libcamera: v4l2_videodevice: Track streaming state","version":1,"mbox":"https://patchwork.libcamera.org/series/541/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/2208/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/2208/checks/","tags":{},"headers":{"Return-Path":"<kieran.bingham@ideasonboard.com>","Received":["from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 4E5EF6137A\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tTue, 22 Oct 2019 18:01:14 +0200 (CEST)","from Q.local (cpc89242-aztw30-2-0-cust488.18-1.cable.virginm.net\n\t[86.31.129.233])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id D006D595;\n\tTue, 22 Oct 2019 18:01:13 +0200 (CEST)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1571760074;\n\tbh=iGjHsSQILInB1Lr4jbGr7cHTBftSYWBb7q1by3kEtuY=;\n\th=From:To:Cc:Subject:Date:From;\n\tb=W/aU2yW/U9Vs5r9t9RZerrDmwmqBWnLhvoc2E6UFZ9Ntv4DPRPVQJnhAo6ZIDrAxE\n\ts9o7jgZThsOs0VkjAWwzRzbhHhGaK56UoozXNmZvarz+C/LdFPlzukjqXDd68vTpwW\n\tJUNefljnN0In389azGT0FMNaUI71aGp0SOiH6OQc=","From":"Kieran Bingham <kieran.bingham@ideasonboard.com>","To":"LibCamera Devel <libcamera-devel@lists.libcamera.org>","Date":"Tue, 22 Oct 2019 17:01:10 +0100","Message-Id":"<20191022160110.19419-1-kieran.bingham@ideasonboard.com>","X-Mailer":"git-send-email 2.20.1","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","Subject":"[libcamera-devel] [RFC PATCH] libcamera: v4l2_videodevice: Track\n\tstreaming state","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"<libcamera-devel.lists.libcamera.org>","List-Unsubscribe":"<https://lists.libcamera.org/options/libcamera-devel>,\n\t<mailto:libcamera-devel-request@lists.libcamera.org?subject=unsubscribe>","List-Archive":"<https://lists.libcamera.org/pipermail/libcamera-devel/>","List-Post":"<mailto:libcamera-devel@lists.libcamera.org>","List-Help":"<mailto:libcamera-devel-request@lists.libcamera.org?subject=help>","List-Subscribe":"<https://lists.libcamera.org/listinfo/libcamera-devel>,\n\t<mailto:libcamera-devel-request@lists.libcamera.org?subject=subscribe>","X-List-Received-Date":"Tue, 22 Oct 2019 16:01:14 -0000"},"content":"Track the state of streamon/streamoff calls to simplify error paths.\n\nEnsuring that streamOff() can be called on non-streaming streams facilitates simpler\nerror code paths, where a set of devices can all call streamOff regardless of their\ninitialisation state.\n\nSigned-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>\n---\n\nThis is a patch I have while developing the RPi ISP handler.\nIt means I can do the following for error paths:\n\n\tdata->isp_.stats_->streamOff();\n\tdata->isp_.capture1_->streamOff();\n \tdata->isp_.capture0_->streamOff();\n \tdata->isp_.output_->streamOff();\n \tdata->unicam_->streamOff();\n\nwhich essentially means I can just call stop(camera) for cleanup, without\nhaving to track which ones were successfully started or not.\n\nSo - Reasonable or not ?\n\nPatch will not apply directly to master, as it's currently based on my dev\nbranch, hence RFC\n\n src/libcamera/include/v4l2_videodevice.h | 2 ++\n src/libcamera/v4l2_videodevice.cpp       | 9 ++++++++-\n 2 files changed, 10 insertions(+), 1 deletion(-)","diff":"diff --git a/src/libcamera/include/v4l2_videodevice.h b/src/libcamera/include/v4l2_videodevice.h\nindex 60fca01670c6..d6e0c0e7bf02 100644\n--- a/src/libcamera/include/v4l2_videodevice.h\n+++ b/src/libcamera/include/v4l2_videodevice.h\n@@ -188,6 +188,8 @@ private:\n \tstd::map<unsigned int, Buffer *> queuedBuffers_;\n \n \tEventNotifier *fdEvent_;\n+\n+\tbool streaming_;\n };\n \n class V4L2M2MDevice\ndiff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp\nindex 71c32766fc2d..01e11597cfb0 100644\n--- a/src/libcamera/v4l2_videodevice.cpp\n+++ b/src/libcamera/v4l2_videodevice.cpp\n@@ -273,7 +273,7 @@ const std::string V4L2DeviceFormat::toString() const\n  */\n V4L2VideoDevice::V4L2VideoDevice(const std::string &deviceNode)\n \t: V4L2Device(deviceNode), multiPlanar_(false), bufferPool_(nullptr),\n-\t  fdEvent_(nullptr)\n+\t  fdEvent_(nullptr), streaming_(false)\n {\n \t/*\n \t * We default to an MMAP based CAPTURE video device, however this will\n@@ -1197,6 +1197,8 @@ int V4L2VideoDevice::streamOn()\n \t\treturn ret;\n \t}\n \n+\tstreaming_ = true;\n+\n \treturn 0;\n }\n \n@@ -1214,6 +1216,9 @@ int V4L2VideoDevice::streamOff()\n {\n \tint ret;\n \n+\tif (!streaming_)\n+\t\treturn 0;\n+\n \tret = ioctl(VIDIOC_STREAMOFF, &bufferType_);\n \tif (ret < 0) {\n \t\tLOG(V4L2, Error)\n@@ -1234,6 +1239,8 @@ int V4L2VideoDevice::streamOff()\n \tqueuedBuffers_.clear();\n \tfdEvent_->setEnabled(false);\n \n+\tstreaming_ = false;\n+\n \treturn 0;\n }\n \n","prefixes":["libcamera-devel","RFC"]}