From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sakari Ailus Subject: [RFC 12/19] v4l2-subdev: Support registering V4L2 sub-device nodes one by one Date: Tue, 18 Jul 2017 22:03:54 +0300 Message-ID: <20170718190401.14797-13-sakari.ailus@linux.intel.com> References: <20170718190401.14797-1-sakari.ailus@linux.intel.com> Return-path: In-Reply-To: <20170718190401.14797-1-sakari.ailus@linux.intel.com> Sender: linux-media-owner@vger.kernel.org To: linux-media@vger.kernel.org Cc: linux-leds@vger.kernel.org, laurent.pinchart@ideasonboard.com, niklas.soderlund@ragnatech.se, hverkuil@xs4all.nl List-Id: linux-leds@vger.kernel.org Just like video devices, V4L2 sub-device nodes can and should be registered as soon as possible. Support this by providing v4l2_device_register_subdev_node() function. v4l2_device_register_subdev_nodes() continues to work just as it used to. Signed-off-by: Sakari Ailus --- drivers/media/v4l2-core/v4l2-device.c | 99 ++++++++++++++++++++--------------- include/media/v4l2-device.h | 12 +++++ 2 files changed, 70 insertions(+), 41 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c index 937c6de85606..0c0c4772c00a 100644 --- a/drivers/media/v4l2-core/v4l2-device.c +++ b/drivers/media/v4l2-core/v4l2-device.c @@ -222,58 +222,75 @@ static void v4l2_device_release_subdev_node(struct video_device *vdev) kfree(vdev); } -int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev) +int v4l2_device_register_subdev_node(struct v4l2_device *v4l2_dev, + struct v4l2_subdev *sd) { struct video_device *vdev; - struct v4l2_subdev *sd; int err; - /* Register a device node for every subdev marked with the - * V4L2_SUBDEV_FL_HAS_DEVNODE flag. - */ - list_for_each_entry(sd, &v4l2_dev->subdevs, list) { - if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE)) - continue; + /* Bail out if the V4L2_SUBDEV_FL_HAS_DEVNODE flag isn't set. */ + if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE)) + return 0; - if (sd->devnode) - continue; + /* Was the device node already registered? If yes, then return here. */ + if (sd->devnode) + return 0; - vdev = kzalloc(sizeof(*vdev), GFP_KERNEL); - if (!vdev) { + vdev = kzalloc(sizeof(*vdev), GFP_KERNEL); + if (!vdev) + return -ENOMEM; + + video_set_drvdata(vdev, sd); + strlcpy(vdev->name, sd->name, sizeof(vdev->name)); + vdev->v4l2_dev = v4l2_dev; + vdev->fops = &v4l2_subdev_fops; + vdev->release = v4l2_device_release_subdev_node; + vdev->ctrl_handler = sd->ctrl_handler; + err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1, + sd->owner); + if (err < 0) + goto clean_up; + + sd->devnode = vdev; +#if defined(CONFIG_MEDIA_CONTROLLER) + sd->entity.info.dev.major = VIDEO_MAJOR; + sd->entity.info.dev.minor = vdev->minor; + + /* Interface is created by __video_register_device() */ + if (vdev->v4l2_dev->mdev) { + struct media_link *link; + + link = media_create_intf_link(&sd->entity, + &vdev->intf_devnode->intf, + MEDIA_LNK_FL_ENABLED); + if (!link) { err = -ENOMEM; goto clean_up; } + } +#endif - video_set_drvdata(vdev, sd); - strlcpy(vdev->name, sd->name, sizeof(vdev->name)); - vdev->v4l2_dev = v4l2_dev; - vdev->fops = &v4l2_subdev_fops; - vdev->release = v4l2_device_release_subdev_node; - vdev->ctrl_handler = sd->ctrl_handler; - err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1, - sd->owner); - if (err < 0) { - kfree(vdev); + return 0; + +clean_up: + video_unregister_device(vdev); + kfree(vdev); + + return err; +} +EXPORT_SYMBOL_GPL(v4l2_device_register_subdev_node); + +int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev) +{ + struct v4l2_subdev *sd; + int err; + + list_for_each_entry(sd, &v4l2_dev->subdevs, list) { + int err; + + err = v4l2_device_register_subdev_node(v4l2_dev, sd); + if (err < 0) goto clean_up; - } - sd->devnode = vdev; -#if defined(CONFIG_MEDIA_CONTROLLER) - sd->entity.info.dev.major = VIDEO_MAJOR; - sd->entity.info.dev.minor = vdev->minor; - - /* Interface is created by __video_register_device() */ - if (vdev->v4l2_dev->mdev) { - struct media_link *link; - - link = media_create_intf_link(&sd->entity, - &vdev->intf_devnode->intf, - MEDIA_LNK_FL_ENABLED); - if (!link) { - err = -ENOMEM; - goto clean_up; - } - } -#endif } return 0; diff --git a/include/media/v4l2-device.h b/include/media/v4l2-device.h index 8ffa94009d1a..8b19c1f5bacd 100644 --- a/include/media/v4l2-device.h +++ b/include/media/v4l2-device.h @@ -189,6 +189,18 @@ int __must_check v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, void v4l2_device_unregister_subdev(struct v4l2_subdev *sd); /** + * v4l2_device_register_subdev_node - Registers device nodes for a subdev + * of the v4l2 device. The call is a no-op unless the + * %V4L2_SUBDEV_FL_HAS_DEVNODE subdev flag is set. + * + * @v4l2_dev: pointer to struct v4l2_device + * @sd: pointer to struct v4l2_subdev + */ +int __must_check +v4l2_device_register_subdev_node(struct v4l2_device *v4l2_dev, + struct v4l2_subdev *sd); + +/** * v4l2_device_register_subdev_nodes - Registers device nodes for all subdevs * of the v4l2 device that are marked with * the %V4L2_SUBDEV_FL_HAS_DEVNODE flag. -- 2.11.0