From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from moutng.kundenserver.de ([212.227.126.186]:60167 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752932Ab1IIPCT (ORCPT ); Fri, 9 Sep 2011 11:02:19 -0400 Date: Fri, 9 Sep 2011 17:02:17 +0200 (CEST) From: Guennadi Liakhovetski To: Linux Media Mailing List cc: Laurent Pinchart , Hans Verkuil Subject: [PATCH] V4L: dynamically allocate video_device nodes in subdevices Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-media-owner@vger.kernel.org List-ID: Currently only very few drivers actually use video_device nodes, embedded in struct v4l2_subdev. Allocate these nodes dynamically for those drivers to save memory for the rest. Signed-off-by: Guennadi Liakhovetski --- Only compile tested. Please, give it a spin on affected hardware. drivers/media/video/v4l2-device.c | 28 +++++++++++++++++++++++++--- include/media/v4l2-subdev.h | 10 ++++++++-- 2 files changed, 33 insertions(+), 5 deletions(-) diff --git a/drivers/media/video/v4l2-device.c b/drivers/media/video/v4l2-device.c index c72856c..0c0f6ba 100644 --- a/drivers/media/video/v4l2-device.c +++ b/drivers/media/video/v4l2-device.c @@ -21,6 +21,7 @@ #include #include #include +#include #if defined(CONFIG_SPI) #include #endif @@ -194,6 +195,7 @@ EXPORT_SYMBOL_GPL(v4l2_device_register_subdev); int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev) { struct video_device *vdev; + struct v4l2_devnode *node; struct v4l2_subdev *sd; int err; @@ -204,7 +206,13 @@ int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev) if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE)) continue; - vdev = &sd->devnode; + node = kzalloc(sizeof(*node), GFP_KERNEL); + if (!node) { + err = -ENOMEM; + goto clean_up; + } + vdev = &node->vdev; + strlcpy(vdev->name, sd->name, sizeof(vdev->name)); vdev->v4l2_dev = v4l2_dev; vdev->fops = &v4l2_subdev_fops; @@ -213,13 +221,25 @@ int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev) err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1, sd->owner); if (err < 0) - return err; + goto clean_up; #if defined(CONFIG_MEDIA_CONTROLLER) sd->entity.v4l.major = VIDEO_MAJOR; sd->entity.v4l.minor = vdev->minor; #endif + sd->devnode = node; } return 0; + +clean_up: + list_for_each_entry(sd, &v4l2_dev->subdevs, list) { + if (!sd->devnode) + break; + video_unregister_device(&sd->devnode->vdev); + kfree(sd->devnode); + sd->devnode = NULL; + } + + return err; } EXPORT_SYMBOL_GPL(v4l2_device_register_subdev_nodes); @@ -245,7 +265,9 @@ void v4l2_device_unregister_subdev(struct v4l2_subdev *sd) if (v4l2_dev->mdev) media_device_unregister_entity(&sd->entity); #endif - video_unregister_device(&sd->devnode); + video_unregister_device(&sd->devnode->vdev); + kfree(sd->devnode); + sd->devnode = NULL; module_put(sd->owner); } EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev); diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index 257da1a..6e958df 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -510,6 +510,12 @@ struct v4l2_subdev_internal_ops { /* Set this flag if this subdev generates events. */ #define V4L2_SUBDEV_FL_HAS_EVENTS (1U << 3) +/* video_device with a reverse lookup */ +struct v4l2_devnode { + struct v4l2_subdev *sd; + struct video_device vdev; +}; + /* Each instance of a subdev driver should create this struct, either stand-alone or embedded in a larger struct. */ @@ -534,13 +540,13 @@ struct v4l2_subdev { void *dev_priv; void *host_priv; /* subdev device node */ - struct video_device devnode; + struct v4l2_devnode *devnode; }; #define media_entity_to_v4l2_subdev(ent) \ container_of(ent, struct v4l2_subdev, entity) #define vdev_to_v4l2_subdev(vdev) \ - container_of(vdev, struct v4l2_subdev, devnode) + (container_of(vdev, struct v4l2_devnode, vdev)->sd) /* * Used for storing subdev information per file handle -- 1.7.2.5