{"id":19187,"url":"https://patchwork.libcamera.org/api/1.1/covers/19187/?format=json","web_url":"https://patchwork.libcamera.org/cover/19187/","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":"<20231102172439.3543870-1-kieran.bingham@ideasonboard.com>","date":"2023-11-02T17:24:37","name":"[libcamera-devel,v3,0/2] Add read-only flag to ControlInfo","submitter":{"id":4,"url":"https://patchwork.libcamera.org/api/1.1/people/4/?format=json","name":"Kieran Bingham","email":"kieran.bingham@ideasonboard.com"},"mbox":"https://patchwork.libcamera.org/cover/19187/mbox/","series":[{"id":4064,"url":"https://patchwork.libcamera.org/api/1.1/series/4064/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=4064","date":"2023-11-02T17:24:37","name":"Add read-only flag to ControlInfo","version":3,"mbox":"https://patchwork.libcamera.org/series/4064/mbox/"}],"comments":"https://patchwork.libcamera.org/api/covers/19187/comments/","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 E9ADEBD16B\n\tfor ;\n\tThu, 2 Nov 2023 17:24:46 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 385FF62991;\n\tThu, 2 Nov 2023 18:24:46 +0100 (CET)","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 D738561DC6\n\tfor ;\n\tThu, 2 Nov 2023 18:24:44 +0100 (CET)","from Monstersaurus.local\n\t(aztw-30-b2-v4wan-166917-cust845.vm26.cable.virginm.net\n\t[82.37.23.78])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 1F6058C1;\n\tThu, 2 Nov 2023 18:24:27 +0100 (CET)"],"DKIM-Signature":["v=1; a=rsa-sha256; c=relaxed/simple; d=libcamera.org;\n\ts=mail; t=1698945886;\n\tbh=ZkbzwoUMXcZNegdS52rCLn2Bs2Ot6PCmyAYY58Fax90=;\n\th=To:Date:Subject:List-Id:List-Unsubscribe:List-Archive:List-Post:\n\tList-Help:List-Subscribe:From:Reply-To:From;\n\tb=MbDbFVicmGP9/CHCmAvSMO1Z62l60Pc7vu6/LbmGDT5TOk6FD4KGlzTVZenlTJnrS\n\t4A/aYcX9DBApMBQg26HshdaRtX74cQYiGKBquIRr+FrEgIEjZFxhFYeMiafUEWsyHE\n\tj11R6tEtLngViwZtIdxiTC1Ki5fgtc22fOPd50+zRNZtQ3wV/btc3o+sFHpudiRXtb\n\t32DdpIuqpyiL8l4/6WzK4HluTvWnN4AOlBYCKpcKAzGE51Q4yy0wWOaddHJGQj5+jw\n\tddgTb5Lzm9cK5eX2z/NeD2U6WcYiPOj1Mnplw5zsnlu44RnOqYlJHeNLTD9LIbl4Es\n\t8U+TE+eXGpYJQ==","v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1698945867;\n\tbh=ZkbzwoUMXcZNegdS52rCLn2Bs2Ot6PCmyAYY58Fax90=;\n\th=From:To:Cc:Subject:Date:From;\n\tb=MucKTqj/oZhlR8EKJgFa6PTqjCWFZjNVvuYf2MMWRr52sE6Puk9pJss45rYWqmFpe\n\tmtXnu5N1PbXXqE1st6ybZOx1ZjeJhey2zC/k4AYiqQ2962Zme2XE+VEXJgPQiS6OmO\n\typ3dxA+sGD57VAtOcAwrKpdvnlBQuGfgZVQUfU48="],"Authentication-Results":"lancelot.ideasonboard.com; dkim=pass (1024-bit key; \n\tunprotected) header.d=ideasonboard.com\n\theader.i=@ideasonboard.com\n\theader.b=\"MucKTqj/\"; dkim-atps=neutral","To":"libcamera devel ","Date":"Thu, 2 Nov 2023 17:24:37 +0000","Message-Id":"<20231102172439.3543870-1-kieran.bingham@ideasonboard.com>","X-Mailer":"git-send-email 2.34.1","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","Subject":"[libcamera-devel] [PATCH v3 0/2] Add read-only flag to ControlInfo","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","From":"Kieran Bingham via libcamera-devel\n\t","Reply-To":"Kieran Bingham ","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "},"content":"This small patch series adds a read-only flag to ControlInfo. This is used\nto test if a control, in particular V4L2_CID_HBLANK, can be written to by\nuserland. It replaces the slightly fragile workaround we have right now where\nwe test if the min and max values of a control are the same to determine if\na control is read-only.\n\nOnly modified one ControlInfo constructor is modified which is used by the\nV4L2Device class to allow this flag to be set, as setting it for a non-v4l2\ncontrol probably does not make sense at this point.\n\nModifying other ControlInfo constructors fails quite quickly falling\ninto a range of template issues due to multiple signatures matching.\n\nThe alternative here would be to rework this such that the ReadOnly flag\ncould be set /after/ construction with a setter allowing something like:\n\nV4L2_CTRL_TYPE_INTEGER64:\n \t\treturn ControlInfo(static_cast(ctrl.minimum),\n \t\t\t\t static_cast(ctrl.maximum),\n-\t\t\t\t static_cast(ctrl.default_value));\n+\t\t\t\t static_cast(ctrl.default_value))\n\t\t\t\t\t.setReadOnly(ctrl.flags & V4L2_CTRL_FLAG_READ_ONLY);\n\nOf course that feels like it could remove the 'contract' of the read\nonly property by opening up the ability for a ReadOnly control to have\nthe ReadOnly flag unset - or by opening up the ability to arbitrarily\naffect a 'property' of a ControlInfo after it has been made.\n\n\nSince v2, I have made the following changes to Naush' patches:\n - Initialised ReadOnly flag as false for ControlInfo(Span<>)\n - Improved documentation\n\nNaushir Patuck (2):\n libcamera: controls: Add read-only flag to ControlInfo\n libcamera:camera_sensor, ipa: raspberrypi: Test readOnly() for HBLANK\n control\n\n include/libcamera/controls.h | 5 ++++-\n src/ipa/rpi/common/ipa_base.cpp | 12 +-----------\n src/libcamera/camera_sensor.cpp | 14 ++------------\n src/libcamera/controls.cpp | 22 ++++++++++++++++++----\n src/libcamera/v4l2_device.cpp | 12 ++++++++----\n 5 files changed, 33 insertions(+), 32 deletions(-)"}