[{"id":2371,"web_url":"https://patchwork.libcamera.org/comment/2371/","msgid":"<20190809224850.GI5007@pendragon.ideasonboard.com>","date":"2019-08-09T22:48:50","subject":"Re: [libcamera-devel] [PATCH v2 1/6] libcamera: v4l2_device: Add\n\tsetFd()","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi Kieran,\n\nThank you for the patch.\n\nOn Fri, Aug 09, 2019 at 04:04:54PM +0100, Kieran Bingham wrote:\n> Provide a means for V4L2 device instances to set the fd_ explicitly.\n> This allows for V4L2Devices to operate when they must use an external\n> open() call.\n> \n> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>\n> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>\n> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>\n> ---\n>  src/libcamera/include/v4l2_device.h |  1 +\n>  src/libcamera/v4l2_device.cpp       | 26 ++++++++++++++++++++++++++\n>  2 files changed, 27 insertions(+)\n> \n> diff --git a/src/libcamera/include/v4l2_device.h b/src/libcamera/include/v4l2_device.h\n> index e7e9829cb05f..7c3af5f6ebe0 100644\n> --- a/src/libcamera/include/v4l2_device.h\n> +++ b/src/libcamera/include/v4l2_device.h\n> @@ -39,6 +39,7 @@ protected:\n>  \tint ioctl(unsigned long request, void *argp);\n>  \n>  \tint fd() { return fd_; }\n> +\tint setFd(int fd);\n>  \n>  private:\n>  \tvoid listControls();\n> diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp\n> index 9a00566a532b..ba4c0d725752 100644\n> --- a/src/libcamera/v4l2_device.cpp\n> +++ b/src/libcamera/v4l2_device.cpp\n> @@ -308,6 +308,32 @@ int V4L2Device::ioctl(unsigned long request, void *argp)\n>   * \\return The V4L2 device file descriptor, -1 if the device node is not open\n>   */\n>  \n> +/**\n> + * \\brief Set the file descriptor of a V4L2 device\n> + * \\param[in] fd The file descriptor handle\n> + *\n> + * This method allows a device to provide an already opened file descriptor\n> + * referring to the V4L2 device node, instead of opening it with open(). This\n> + * can be used for V4L2 M2M devices where a single video device node is used for\n> + * both the output and capture devices, or when receiving an open file\n> + * descriptor in a context that doesn't have permission to open the device node\n> + * itself.\n> + *\n> + * This method and the open() method are mutually exclusive, only one of the two\n> + * shall be used for a V4L2Device instance.\n> + *\n> + * \\return 0 on success or a negative error code otherwise\n> + */\n> +int V4L2Device::setFd(int fd)\n> +{\n> +\tif (fd_ != -1)\n> +\t\treturn -1;\n\nJust one more comment, would -EBUSY be more appropriate ?\n\n> +\n> +\tfd_ = fd;\n> +\n> +\treturn 0;\n> +}\n> +\n>  /*\n>   * \\brief List and store information about all controls supported by the\n>   * V4L2 device","headers":{"Return-Path":"<laurent.pinchart@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 A7D5B60E2F\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tSat, 10 Aug 2019 00:48:53 +0200 (CEST)","from pendragon.ideasonboard.com\n\t(dfj612yhrgyx302h3jwwy-3.rev.dnainternet.fi\n\t[IPv6:2001:14ba:21f5:5b00:ce28:277f:58d7:3ca4])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id EC7B467;\n\tSat, 10 Aug 2019 00:48:52 +0200 (CEST)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1565390933;\n\tbh=Aw5+mvGmPytoB9mDmh0DbHdBf30SZ9PKpzCPfVn49D8=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=pfhtWwp9Qvz08brASrFZahOwNP/HoT+Mfz/wp/2H7rx0VXilOYPtH+nqzNtgK0k0j\n\tXChSJBz4TmICKqKd8TZTPEaxTSp+r3jh0Ig0cDcJ5U5IUAV6lMuZw5cknbaI2U0JgY\n\trzt+IV7irMg5W+eclUMqWbWa5eQofNx7NSnmwb98=","Date":"Sat, 10 Aug 2019 01:48:50 +0300","From":"Laurent Pinchart <laurent.pinchart@ideasonboard.com>","To":"Kieran Bingham <kieran.bingham@ideasonboard.com>","Cc":"LibCamera Devel <libcamera-devel@lists.libcamera.org>,\n\tJacopo Mondi <jacopo@jmondi.org>","Message-ID":"<20190809224850.GI5007@pendragon.ideasonboard.com>","References":"<20190809150459.14421-1-kieran.bingham@ideasonboard.com>\n\t<20190809150459.14421-2-kieran.bingham@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<20190809150459.14421-2-kieran.bingham@ideasonboard.com>","User-Agent":"Mutt/1.10.1 (2018-07-13)","Subject":"Re: [libcamera-devel] [PATCH v2 1/6] libcamera: v4l2_device: Add\n\tsetFd()","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.23","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":"Fri, 09 Aug 2019 22:48:53 -0000"}},{"id":2378,"web_url":"https://patchwork.libcamera.org/comment/2378/","msgid":"<8abe6c31-c0ca-f5e9-c06f-f4cd68d7b56a@ideasonboard.com>","date":"2019-08-12T07:20:40","subject":"Re: [libcamera-devel] [PATCH v2 1/6] libcamera: v4l2_device: Add\n\tsetFd()","submitter":{"id":4,"url":"https://patchwork.libcamera.org/api/people/4/","name":"Kieran Bingham","email":"kieran.bingham@ideasonboard.com"},"content":"On 09/08/2019 23:48, Laurent Pinchart wrote:\n> Hi Kieran,\n> \n> Thank you for the patch.\n> \n> On Fri, Aug 09, 2019 at 04:04:54PM +0100, Kieran Bingham wrote:\n>> Provide a means for V4L2 device instances to set the fd_ explicitly.\n>> This allows for V4L2Devices to operate when they must use an external\n>> open() call.\n>>\n>> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>\n>> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>\n>> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>\n>> ---\n>>  src/libcamera/include/v4l2_device.h |  1 +\n>>  src/libcamera/v4l2_device.cpp       | 26 ++++++++++++++++++++++++++\n>>  2 files changed, 27 insertions(+)\n>>\n>> diff --git a/src/libcamera/include/v4l2_device.h b/src/libcamera/include/v4l2_device.h\n>> index e7e9829cb05f..7c3af5f6ebe0 100644\n>> --- a/src/libcamera/include/v4l2_device.h\n>> +++ b/src/libcamera/include/v4l2_device.h\n>> @@ -39,6 +39,7 @@ protected:\n>>  \tint ioctl(unsigned long request, void *argp);\n>>  \n>>  \tint fd() { return fd_; }\n>> +\tint setFd(int fd);\n>>  \n>>  private:\n>>  \tvoid listControls();\n>> diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp\n>> index 9a00566a532b..ba4c0d725752 100644\n>> --- a/src/libcamera/v4l2_device.cpp\n>> +++ b/src/libcamera/v4l2_device.cpp\n>> @@ -308,6 +308,32 @@ int V4L2Device::ioctl(unsigned long request, void *argp)\n>>   * \\return The V4L2 device file descriptor, -1 if the device node is not open\n>>   */\n>>  \n>> +/**\n>> + * \\brief Set the file descriptor of a V4L2 device\n>> + * \\param[in] fd The file descriptor handle\n>> + *\n>> + * This method allows a device to provide an already opened file descriptor\n>> + * referring to the V4L2 device node, instead of opening it with open(). This\n>> + * can be used for V4L2 M2M devices where a single video device node is used for\n>> + * both the output and capture devices, or when receiving an open file\n>> + * descriptor in a context that doesn't have permission to open the device node\n>> + * itself.\n>> + *\n>> + * This method and the open() method are mutually exclusive, only one of the two\n>> + * shall be used for a V4L2Device instance.\n>> + *\n>> + * \\return 0 on success or a negative error code otherwise\n>> + */\n>> +int V4L2Device::setFd(int fd)\n>> +{\n>> +\tif (fd_ != -1)\n>> +\t\treturn -1;\n> \n> Just one more comment, would -EBUSY be more appropriate ?\n\nYes, probably. I'll update.\n\n> \n>> +\n>> +\tfd_ = fd;\n>> +\n>> +\treturn 0;\n>> +}\n>> +\n>>  /*\n>>   * \\brief List and store information about all controls supported by the\n>>   * V4L2 device\n>","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 2D08960C43\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tMon, 12 Aug 2019 09:20:44 +0200 (CEST)","from [192.168.0.20]\n\t(cpc89242-aztw30-2-0-cust488.18-1.cable.virginm.net [86.31.129.233])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id BC47C327;\n\tMon, 12 Aug 2019 09:20:42 +0200 (CEST)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1565594443;\n\tbh=pyqQvPmLp/Q9UYmAS7WvX49j7wb3Thd6WEJnp7/pMtg=;\n\th=Reply-To:Subject:To:Cc:References:From:Date:In-Reply-To:From;\n\tb=b7EZa8NY7zMO82SH09Unmr6AlEsVafeM4yLwjxeSDqBP3iWijrvlpeFwpBkcHEvEk\n\tJbDNfhjLUa0BAPBvwe+lFFK2fT9ZHPOuFW3A8w/sAHaSfwMAEIKT8t3TfBPKOCQZa/\n\tpwToNq60+ppKQPukz+GpUuMirTjVFMf58ZgJpSgM=","Reply-To":"kieran.bingham@ideasonboard.com","To":"Laurent Pinchart <laurent.pinchart@ideasonboard.com>","Cc":"LibCamera Devel <libcamera-devel@lists.libcamera.org>,\n\tJacopo Mondi <jacopo@jmondi.org>","References":"<20190809150459.14421-1-kieran.bingham@ideasonboard.com>\n\t<20190809150459.14421-2-kieran.bingham@ideasonboard.com>\n\t<20190809224850.GI5007@pendragon.ideasonboard.com>","From":"Kieran Bingham <kieran.bingham@ideasonboard.com>","Openpgp":"preference=signencrypt","Autocrypt":"addr=kieran.bingham@ideasonboard.com; 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Linux x86_64; rv:60.0) Gecko/20100101\n\tThunderbird/60.8.0","MIME-Version":"1.0","In-Reply-To":"<20190809224850.GI5007@pendragon.ideasonboard.com>","Content-Type":"text/plain; charset=utf-8","Content-Language":"en-GB","Content-Transfer-Encoding":"7bit","Subject":"Re: [libcamera-devel] [PATCH v2 1/6] libcamera: v4l2_device: Add\n\tsetFd()","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.23","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":"Mon, 12 Aug 2019 07:20:44 -0000"}},{"id":2382,"web_url":"https://patchwork.libcamera.org/comment/2382/","msgid":"<44a7a00a-25b7-fcb2-ed25-d5eea847d63a@ideasonboard.com>","date":"2019-08-12T09:13:01","subject":"Re: [libcamera-devel] [PATCH v2 1/6] libcamera: v4l2_device: Add\n\tsetFd()","submitter":{"id":4,"url":"https://patchwork.libcamera.org/api/people/4/","name":"Kieran Bingham","email":"kieran.bingham@ideasonboard.com"},"content":"Hi Laurent,\n\nOn 12/08/2019 08:20, Kieran Bingham wrote:\n> \n> \n> On 09/08/2019 23:48, Laurent Pinchart wrote:\n>> Hi Kieran,\n>>\n>> Thank you for the patch.\n>>\n>> On Fri, Aug 09, 2019 at 04:04:54PM +0100, Kieran Bingham wrote:\n>>> Provide a means for V4L2 device instances to set the fd_ explicitly.\n>>> This allows for V4L2Devices to operate when they must use an external\n>>> open() call.\n>>>\n>>> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>\n>>> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>\n>>> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>\n>>> ---\n>>>  src/libcamera/include/v4l2_device.h |  1 +\n>>>  src/libcamera/v4l2_device.cpp       | 26 ++++++++++++++++++++++++++\n>>>  2 files changed, 27 insertions(+)\n>>>\n>>> diff --git a/src/libcamera/include/v4l2_device.h b/src/libcamera/include/v4l2_device.h\n>>> index e7e9829cb05f..7c3af5f6ebe0 100644\n>>> --- a/src/libcamera/include/v4l2_device.h\n>>> +++ b/src/libcamera/include/v4l2_device.h\n>>> @@ -39,6 +39,7 @@ protected:\n>>>  \tint ioctl(unsigned long request, void *argp);\n>>>  \n>>>  \tint fd() { return fd_; }\n>>> +\tint setFd(int fd);\n>>>  \n>>>  private:\n>>>  \tvoid listControls();\n>>> diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp\n>>> index 9a00566a532b..ba4c0d725752 100644\n>>> --- a/src/libcamera/v4l2_device.cpp\n>>> +++ b/src/libcamera/v4l2_device.cpp\n>>> @@ -308,6 +308,32 @@ int V4L2Device::ioctl(unsigned long request, void *argp)\n>>>   * \\return The V4L2 device file descriptor, -1 if the device node is not open\n>>>   */\n>>>  \n>>> +/**\n>>> + * \\brief Set the file descriptor of a V4L2 device\n>>> + * \\param[in] fd The file descriptor handle\n>>> + *\n>>> + * This method allows a device to provide an already opened file descriptor\n>>> + * referring to the V4L2 device node, instead of opening it with open(). This\n>>> + * can be used for V4L2 M2M devices where a single video device node is used for\n>>> + * both the output and capture devices, or when receiving an open file\n>>> + * descriptor in a context that doesn't have permission to open the device node\n>>> + * itself.\n>>> + *\n>>> + * This method and the open() method are mutually exclusive, only one of the two\n>>> + * shall be used for a V4L2Device instance.\n>>> + *\n>>> + * \\return 0 on success or a negative error code otherwise\n>>> + */\n>>> +int V4L2Device::setFd(int fd)\n>>> +{\n>>> +\tif (fd_ != -1)\n>>> +\t\treturn -1;\n>>\n>> Just one more comment, would -EBUSY be more appropriate ?\n> \n> Yes, probably. I'll update.\n\nThis should really be:\n\n\tif (isOpen())\n\t\treturn -EBUSY;\n\nto match the open() call.\n\nThen I think setFd() should move up in the file to between open() and\nclose() too.\n\nI'll update for the next version.\n\n\n>>\n>>> +\n>>> +\tfd_ = fd;\n>>> +\n>>> +\treturn 0;\n>>> +}\n>>> +\n>>>  /*\n>>>   * \\brief List and store information about all controls supported by the\n>>>   * V4L2 device\n>>\n>","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 B544860E38\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tMon, 12 Aug 2019 11:13:04 +0200 (CEST)","from [192.168.0.20]\n\t(cpc89242-aztw30-2-0-cust488.18-1.cable.virginm.net [86.31.129.233])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 06E7E327;\n\tMon, 12 Aug 2019 11:13:03 +0200 (CEST)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1565601184;\n\tbh=wsj9hXp1JUKi1MBXxFjDzERr06vO13u1HwUEjEQ78fI=;\n\th=Reply-To:Subject:From:To:Cc:References:Date:In-Reply-To:From;\n\tb=jJq7d0ugRMMelZ5b40CyFzrTPDpnFbLsIptnYAgT5WLD6yQk564y/WGTp/e1hDOlz\n\ta/7gFEigMX7wfZ37+mYI0QL5qWPCmvlGy2OQ15feGv0ZwANCu+n+G2mttt8EbOWOEQ\n\tuIXAKGEn4N+3c7dUI227VHdcd9+nCdWLCRuF9DGw=","Reply-To":"kieran.bingham@ideasonboard.com","From":"Kieran Bingham <kieran.bingham@ideasonboard.com>","To":"Laurent Pinchart <laurent.pinchart@ideasonboard.com>","Cc":"LibCamera Devel <libcamera-devel@lists.libcamera.org>,\n\tJacopo Mondi <jacopo@jmondi.org>","References":"<20190809150459.14421-1-kieran.bingham@ideasonboard.com>\n\t<20190809150459.14421-2-kieran.bingham@ideasonboard.com>\n\t<20190809224850.GI5007@pendragon.ideasonboard.com>\n\t<8abe6c31-c0ca-f5e9-c06f-f4cd68d7b56a@ideasonboard.com>","Openpgp":"preference=signencrypt","Autocrypt":"addr=kieran.bingham@ideasonboard.com; keydata=\n\tmQINBFYE/WYBEACs1PwjMD9rgCu1hlIiUA1AXR4rv2v+BCLUq//vrX5S5bjzxKAryRf0uHat\n\tV/zwz6hiDrZuHUACDB7X8OaQcwhLaVlq6byfoBr25+hbZG7G3+5EUl9cQ7dQEdvNj6V6y/SC\n\trRanWfelwQThCHckbobWiQJfK9n7rYNcPMq9B8e9F020LFH7Kj6YmO95ewJGgLm+idg1Kb3C\n\tpotzWkXc1xmPzcQ1fvQMOfMwdS+4SNw4rY9f07Xb2K99rjMwZVDgESKIzhsDB5GY465sCsiQ\n\tcSAZRxqE49RTBq2+EQsbrQpIc8XiffAB8qexh5/QPzCmR4kJgCGeHIXBtgRj+nIkCJPZvZtf\n\tKr2EAbc6tgg6DkAEHJb+1okosV09+0+TXywYvtEop/WUOWQ+zo+Y/OBd+8Ptgt1pDRyOBzL8\n\tRXa8ZqRf0Mwg75D+dKntZeJHzPRJyrlfQokngAAs4PaFt6UfS+ypMAF37T6CeDArQC41V3ko\n\tlPn1yMsVD0p+6i3DPvA/GPIksDC4owjnzVX9kM8Zc5Cx+XoAN0w5Eqo4t6qEVbuettxx55gq\n\t8K8FieAjgjMSxngo/HST8TpFeqI5nVeq0/lqtBRQKumuIqDg+Bkr4L1V/PSB6XgQcOdhtd36\n\tOe9X9dXB8YSNt7VjOcO7BTmFn/Z8r92mSAfHXpb07YJWJosQOQARAQABtDBLaWVyYW4gQmlu\n\tZ2hhbSA8a2llcmFuLmJpbmdoYW1AaWRlYXNvbmJvYXJkLmNvbT6JAkAEEwEKACoCGwMFCwkI\n\tBwIGFQgJCgsCBBYCAwECHgECF4ACGQEFAlnDk/gFCQeA/YsACgkQoR5GchCkYf3X5w/9EaZ7\n\tcnUcT6dxjxrcmmMnfFPoQA1iQXr/MXQJBjFWfxRUWYzjvUJb2D/FpA8FY7y+vksoJP7pWDL7\n\tQTbksdwzagUEk7CU45iLWL/CZ/knYhj1I/+5LSLFmvZ/5Gf5xn2ZCsmg7C0MdW/GbJ8IjWA8\n\t/LKJSEYH8tefoiG6+9xSNp1p0Gesu3vhje/GdGX4wDsfAxx1rIYDYVoX4bDM+uBUQh7sQox/\n\tR1bS0AaVJzPNcjeC14MS226mQRUaUPc9250aj44WmDfcg44/kMsoLFEmQo2II9aOlxUDJ+x1\n\txohGbh9mgBoVawMO3RMBihcEjo/8ytW6v7xSF+xP4Oc+HOn7qebAkxhSWcRxQVaQYw3S9iZz\n\t2iA09AXAkbvPKuMSXi4uau5daXStfBnmOfalG0j+9Y6hOFjz5j0XzaoF6Pln0jisDtWltYhP\n\tX9LjFVhhLkTzPZB/xOeWGmsG4gv2V2ExbU3uAmb7t1VSD9+IO3Km4FtnYOKBWlxwEd8qOFpS\n\tjEqMXURKOiJvnw3OXe9MqG19XdeENA1KyhK5rqjpwdvPGfSn2V+SlsdJA0DFsobUScD9qXQw\n\tOvhapHe3XboK2+Rd7L+g/9Ud7ZKLQHAsMBXOVJbufA1AT+IaOt0ugMcFkAR5UbBg5+dZUYJj\n\t1QbPQcGmM3wfvuaWV5+SlJ+WeKIb8ta5Ag0EVgT9ZgEQAM4o5G/kmruIQJ3K9SYzmPishRHV\n\tDcUcvoakyXSX2mIoccmo9BHtD9MxIt+QmxOpYFNFM7YofX4lG0ld8H7FqoNVLd/+a0yru5Cx\n\tadeZBe3qr1eLns10Q90LuMo7/6zJhCW2w+HE7xgmCHejAwuNe3+7yt4QmwlSGUqdxl8cgtS1\n\tPlEK93xXDsgsJj/bw1EfSVdAUqhx8UQ3aVFxNug5OpoX9FdWJLKROUrfNeBE16RLrNrq2ROc\n\tiSFETpVjyC/oZtzRFnwD9Or7EFMi76/xrWzk+/b15RJ9WrpXGMrttHUUcYZEOoiC2lEXMSAF\n\tSSSj4vHbKDJ0vKQdEFtdgB1roqzxdIOg4rlHz5qwOTynueiBpaZI3PHDudZSMR5Fk6QjFooE\n\tXTw3sSl/km/lvUFiv9CYyHOLdygWohvDuMkV/Jpdkfq8XwFSjOle+vT/4VqERnYFDIGBxaRx\n\tkoBLfNDiiuR3lD8tnJ4A1F88K6ojOUs+jndKsOaQpDZV6iNFv8IaNIklTPvPkZsmNDhJMRHH\n\tIu60S7BpzNeQeT4yyY4dX9lC2JL/LOEpw8DGf5BNOP1KgjCvyp1/KcFxDAo89IeqljaRsCdP\n\t7WCIECWYem6pLwaw6IAL7oX+tEqIMPph/G/jwZcdS6Hkyt/esHPuHNwX4guqTbVEuRqbDzDI\n\t2DJO5FbxABEBAAGJAiUEGAEKAA8CGwwFAlnDlGsFCQeA/gIACgkQoR5GchCkYf1yYRAAq+Yo\n\tnbf9DGdK1kTAm2RTFg+w9oOp2Xjqfhds2PAhFFvrHQg1XfQR/UF/SjeUmaOmLSczM0s6XMeO\n\tVcE77UFtJ/+hLo4PRFKm5X1Pcar6g5m4xGqa+Xfzi9tRkwC29KMCoQOag1BhHChgqYaUH3yo\n\tUzaPwT/fY75iVI+yD0ih/e6j8qYvP8pvGwMQfrmN9YB0zB39YzCSdaUaNrWGD3iCBxg6lwSO\n\tLKeRhxxfiXCIYEf3vwOsP3YMx2JkD5doseXmWBGW1U0T/oJF+DVfKB6mv5UfsTzpVhJRgee7\n\t4jkjqFq4qsUGxcvF2xtRkfHFpZDbRgRlVmiWkqDkT4qMA+4q1y/dWwshSKi/uwVZNycuLsz+\n\t+OD8xPNCsMTqeUkAKfbD8xW4LCay3r/dD2ckoxRxtMD9eOAyu5wYzo/ydIPTh1QEj9SYyvp8\n\tO0g6CpxEwyHUQtF5oh15O018z3ZLztFJKR3RD42VKVsrnNDKnoY0f4U0z7eJv2NeF8xHMuiU\n\tRCIzqxX1GVYaNkKTnb/Qja8hnYnkUzY1Lc+OtwiGmXTwYsPZjjAaDX35J/RSKAoy5wGo/YFA\n\tJxB1gWThL4kOTbsqqXj9GLcyOImkW0lJGGR3o/fV91Zh63S5TKnf2YGGGzxki+ADdxVQAm+Q\n\tsbsRB8KNNvVXBOVNwko86rQqF9drZuw=","Organization":"Ideas on Board","Message-ID":"<44a7a00a-25b7-fcb2-ed25-d5eea847d63a@ideasonboard.com>","Date":"Mon, 12 Aug 2019 10:13:01 +0100","User-Agent":"Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101\n\tThunderbird/60.8.0","MIME-Version":"1.0","In-Reply-To":"<8abe6c31-c0ca-f5e9-c06f-f4cd68d7b56a@ideasonboard.com>","Content-Type":"text/plain; charset=utf-8","Content-Language":"en-GB","Content-Transfer-Encoding":"8bit","Subject":"Re: [libcamera-devel] [PATCH v2 1/6] libcamera: v4l2_device: Add\n\tsetFd()","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.23","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":"Mon, 12 Aug 2019 09:13:04 -0000"}},{"id":2388,"web_url":"https://patchwork.libcamera.org/comment/2388/","msgid":"<20190812100612.GD5006@pendragon.ideasonboard.com>","date":"2019-08-12T10:06:12","subject":"Re: [libcamera-devel] [PATCH v2 1/6] libcamera: v4l2_device: Add\n\tsetFd()","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"content":"Hi Kieran,\n\nOn Mon, Aug 12, 2019 at 10:13:01AM +0100, Kieran Bingham wrote:\n> On 12/08/2019 08:20, Kieran Bingham wrote:\n> > On 09/08/2019 23:48, Laurent Pinchart wrote:\n> >> On Fri, Aug 09, 2019 at 04:04:54PM +0100, Kieran Bingham wrote:\n> >>> Provide a means for V4L2 device instances to set the fd_ explicitly.\n> >>> This allows for V4L2Devices to operate when they must use an external\n> >>> open() call.\n> >>>\n> >>> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>\n> >>> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>\n> >>> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>\n> >>> ---\n> >>>  src/libcamera/include/v4l2_device.h |  1 +\n> >>>  src/libcamera/v4l2_device.cpp       | 26 ++++++++++++++++++++++++++\n> >>>  2 files changed, 27 insertions(+)\n> >>>\n> >>> diff --git a/src/libcamera/include/v4l2_device.h b/src/libcamera/include/v4l2_device.h\n> >>> index e7e9829cb05f..7c3af5f6ebe0 100644\n> >>> --- a/src/libcamera/include/v4l2_device.h\n> >>> +++ b/src/libcamera/include/v4l2_device.h\n> >>> @@ -39,6 +39,7 @@ protected:\n> >>>  \tint ioctl(unsigned long request, void *argp);\n> >>>  \n> >>>  \tint fd() { return fd_; }\n> >>> +\tint setFd(int fd);\n> >>>  \n> >>>  private:\n> >>>  \tvoid listControls();\n> >>> diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp\n> >>> index 9a00566a532b..ba4c0d725752 100644\n> >>> --- a/src/libcamera/v4l2_device.cpp\n> >>> +++ b/src/libcamera/v4l2_device.cpp\n> >>> @@ -308,6 +308,32 @@ int V4L2Device::ioctl(unsigned long request, void *argp)\n> >>>   * \\return The V4L2 device file descriptor, -1 if the device node is not open\n> >>>   */\n> >>>  \n> >>> +/**\n> >>> + * \\brief Set the file descriptor of a V4L2 device\n> >>> + * \\param[in] fd The file descriptor handle\n> >>> + *\n> >>> + * This method allows a device to provide an already opened file descriptor\n> >>> + * referring to the V4L2 device node, instead of opening it with open(). This\n> >>> + * can be used for V4L2 M2M devices where a single video device node is used for\n> >>> + * both the output and capture devices, or when receiving an open file\n> >>> + * descriptor in a context that doesn't have permission to open the device node\n> >>> + * itself.\n> >>> + *\n> >>> + * This method and the open() method are mutually exclusive, only one of the two\n> >>> + * shall be used for a V4L2Device instance.\n> >>> + *\n> >>> + * \\return 0 on success or a negative error code otherwise\n> >>> + */\n> >>> +int V4L2Device::setFd(int fd)\n> >>> +{\n> >>> +\tif (fd_ != -1)\n> >>> +\t\treturn -1;\n> >>\n> >> Just one more comment, would -EBUSY be more appropriate ?\n> > \n> > Yes, probably. I'll update.\n> \n> This should really be:\n> \n> \tif (isOpen())\n> \t\treturn -EBUSY;\n> \n> to match the open() call.\n> \n> Then I think setFd() should move up in the file to between open() and\n> close() too.\n\nSounds good to me, you can keep my Rb.\n\n> I'll update for the next version.\n> \n> >>> +\n> >>> +\tfd_ = fd;\n> >>> +\n> >>> +\treturn 0;\n> >>> +}\n> >>> +\n> >>>  /*\n> >>>   * \\brief List and store information about all controls supported by the\n> >>>   * V4L2 device","headers":{"Return-Path":"<laurent.pinchart@ideasonboard.com>","Received":["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 AC8EE61582\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tMon, 12 Aug 2019 12:06:15 +0200 (CEST)","from pendragon.ideasonboard.com\n\t(dfj612yhrgyx302h3jwwy-3.rev.dnainternet.fi\n\t[IPv6:2001:14ba:21f5:5b00:ce28:277f:58d7:3ca4])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 177A9327;\n\tMon, 12 Aug 2019 12:06:15 +0200 (CEST)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1565604375;\n\tbh=gBzszyaQMf1DJwe+ql/2MkztuFMIKYJA4rB3ofEOjME=;\n\th=Date:From:To:Cc:Subject:References:In-Reply-To:From;\n\tb=tsFTW2Z5EdKQTa3AxF3G+we6ctqyPqGcaQCeX/mSkItrTneujs8VFCGz7uIOcNhRH\n\tHDj6clD2kjO+cWsbxJ6deTNQaEDPbYd1qEYb9u68s+/StCJZs17xSNIb8cf6AYeKcM\n\tWrfdXX5D7/zVbibZtW+36/blHfyTI0Iv1xkMBvts=","Date":"Mon, 12 Aug 2019 13:06:12 +0300","From":"Laurent Pinchart <laurent.pinchart@ideasonboard.com>","To":"Kieran Bingham <kieran.bingham@ideasonboard.com>","Cc":"LibCamera Devel <libcamera-devel@lists.libcamera.org>,\n\tJacopo Mondi <jacopo@jmondi.org>","Message-ID":"<20190812100612.GD5006@pendragon.ideasonboard.com>","References":"<20190809150459.14421-1-kieran.bingham@ideasonboard.com>\n\t<20190809150459.14421-2-kieran.bingham@ideasonboard.com>\n\t<20190809224850.GI5007@pendragon.ideasonboard.com>\n\t<8abe6c31-c0ca-f5e9-c06f-f4cd68d7b56a@ideasonboard.com>\n\t<44a7a00a-25b7-fcb2-ed25-d5eea847d63a@ideasonboard.com>","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Disposition":"inline","In-Reply-To":"<44a7a00a-25b7-fcb2-ed25-d5eea847d63a@ideasonboard.com>","User-Agent":"Mutt/1.10.1 (2018-07-13)","Subject":"Re: [libcamera-devel] [PATCH v2 1/6] libcamera: v4l2_device: Add\n\tsetFd()","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.23","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":"Mon, 12 Aug 2019 10:06:15 -0000"}}]