From patchwork Thu May 7 15:12:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 3707 X-Patchwork-Delegate: jacopo@jmondi.org Return-Path: Received: from relay12.mail.gandi.net (relay12.mail.gandi.net [217.70.178.232]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 155A4603EA for ; Thu, 7 May 2020 17:09:57 +0200 (CEST) Received: from localhost.localdomain (2-224-242-101.ip172.fastwebnet.it [2.224.242.101]) (Authenticated sender: jacopo@jmondi.org) by relay12.mail.gandi.net (Postfix) with ESMTPSA id 1B3DA20000A; Thu, 7 May 2020 15:09:54 +0000 (UTC) From: Jacopo Mondi To: linux-media@vger.kernel.org, libcamera-devel@lists.libcamera.org Cc: Jacopo Mondi , mchehab@kernel.org, hverkuil-cisco@xs4all.nl, sakari.ailus@linux.intel.com, andrey.konovalov@linaro.org, laurent.pinchart@ideasonboard.com, Hans Verkuil Date: Thu, 7 May 2020 17:12:52 +0200 Message-Id: <20200507151253.2951492-6-jacopo@jmondi.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200507151253.2951492-1-jacopo@jmondi.org> References: <20200507151253.2951492-1-jacopo@jmondi.org> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v7 5/6] v4l2-subdev: add VIDIOC_SUBDEV_QUERYCAP ioctl X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 07 May 2020 15:09:57 -0000 From: Hans Verkuil While normal video/radio/vbi/swradio nodes have a proper QUERYCAP ioctl that apps can call to determine that it is indeed a V4L2 device, there is currently no equivalent for v4l-subdev nodes. Adding this ioctl will solve that, and it will allow utilities like v4l2-compliance to be used with these devices as well. SUBDEV_QUERYCAP currently returns the version and capabilities of the subdevice. Define a capability flag to report if the subdevice is registered in read-only mode. Signed-off-by: Hans Verkuil Signed-off-by: Jacopo Mondi --- drivers/media/v4l2-core/v4l2-subdev.c | 11 +++++++++++ include/uapi/linux/v4l2-subdev.h | 16 ++++++++++++++++ 2 files changed, 27 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c index 174778f9c0bc4..665b0c0f74cf8 100644 --- a/drivers/media/v4l2-core/v4l2-subdev.c +++ b/drivers/media/v4l2-core/v4l2-subdev.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -344,6 +345,16 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg) int rval; switch (cmd) { + case VIDIOC_SUBDEV_QUERYCAP: { + struct v4l2_subdev_capability *cap = arg; + + memset(cap->reserved, 0, sizeof(cap->reserved)); + cap->version = LINUX_VERSION_CODE; + cap->capabilities = ro_subdev ? V4L2_SUBDEV_CAP_RO_SUBDEV : 0; + + return 0; + } + case VIDIOC_QUERYCTRL: /* * TODO: this really should be folded into v4l2_queryctrl (this diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h index 03970ce307419..5d2a1dab79112 100644 --- a/include/uapi/linux/v4l2-subdev.h +++ b/include/uapi/linux/v4l2-subdev.h @@ -155,9 +155,25 @@ struct v4l2_subdev_selection { __u32 reserved[8]; }; +/** + * struct v4l2_subdev_capability - subdev capabilities + * @version: the driver versioning number + * @capabilities: the subdev capabilities, see V4L2_SUBDEV_CAP_* + * @reserved: for future use, set to zero for now + */ +struct v4l2_subdev_capability { + __u32 version; + __u32 capabilities; + __u32 reserved[14]; +}; + +/* The v4l2 sub-device video device node is registered in read-only mode. */ +#define V4L2_SUBDEV_CAP_RO_SUBDEV BIT(0) + /* Backwards compatibility define --- to be removed */ #define v4l2_subdev_edid v4l2_edid +#define VIDIOC_SUBDEV_QUERYCAP _IOR('V', 0, struct v4l2_subdev_capability) #define VIDIOC_SUBDEV_G_FMT _IOWR('V', 4, struct v4l2_subdev_format) #define VIDIOC_SUBDEV_S_FMT _IOWR('V', 5, struct v4l2_subdev_format) #define VIDIOC_SUBDEV_G_FRAME_INTERVAL _IOWR('V', 21, struct v4l2_subdev_frame_interval)