This patch adds a list of v4l2_fh structures to every video_device.
It allows using file handle related information in V4L2. The event interface
is one example of such use.
Video device drivers should use the v4l2_fh pointer as their
file->private_data.
Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxxxxxxxxxxxxx>
---
drivers/media/video/Makefile | 2 +-
drivers/media/video/v4l2-dev.c | 4 ++
drivers/media/video/v4l2-fh.c | 64 ++++++++++++++++++++++++++++++++++++++++
include/media/v4l2-dev.h | 5 +++
include/media/v4l2-fh.h | 42 ++++++++++++++++++++++++++
5 files changed, 116 insertions(+), 1 deletions(-)
create mode 100644 drivers/media/video/v4l2-fh.c
create mode 100644 include/media/v4l2-fh.h
diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile
index 5163289..14bf69a 100644
--- a/drivers/media/video/Makefile
+++ b/drivers/media/video/Makefile
@@ -10,7 +10,7 @@ stkwebcam-objs := stk-webcam.o stk-sensor.o
omap2cam-objs := omap24xxcam.o omap24xxcam-dma.o
-videodev-objs := v4l2-dev.o v4l2-ioctl.o v4l2-device.o
+videodev-objs := v4l2-dev.o v4l2-ioctl.o v4l2-device.o v4l2-fh.o
# V4L2 core modules
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
index 7090699..65a7b30 100644
--- a/drivers/media/video/v4l2-dev.c
+++ b/drivers/media/video/v4l2-dev.c
@@ -421,6 +421,10 @@ static int __video_register_device(struct video_device *vdev, int type, int nr,
if (!vdev->release)
return -EINVAL;
+ /* v4l2_fh support */
+ spin_lock_init(&vdev->fh_lock);
+ INIT_LIST_HEAD(&vdev->fh_list);
+
/* Part 1: check device type */
switch (type) {
case VFL_TYPE_GRABBER:
diff --git a/drivers/media/video/v4l2-fh.c b/drivers/media/video/v4l2-fh.c
new file mode 100644
index 0000000..c707930
--- /dev/null
+++ b/drivers/media/video/v4l2-fh.c
@@ -0,0 +1,64 @@
+/*
+ * drivers/media/video/v4l2-fh.c
+ *
+ * V4L2 file handles.
+ *
+ * Copyright (C) 2009 Nokia Corporation.
+ *
+ * Contact: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxxxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/bitops.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-fh.h>
+
+void v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
+{
+ fh->vdev = vdev;
+ INIT_LIST_HEAD(&fh->list);
+ set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags);
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_init);
+
+void v4l2_fh_add(struct v4l2_fh *fh)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+ list_add(&fh->list, &fh->vdev->fh_list);
+ spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_add);
+
+void v4l2_fh_del(struct v4l2_fh *fh)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+ list_del_init(&fh->list);
+ spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_del);
+
+void v4l2_fh_exit(struct v4l2_fh *fh)
+{
+ if (fh->vdev == NULL)
+ return;
+
+ fh->vdev = NULL;
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_exit);
diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
index 2dee938..bebe44b 100644
--- a/include/media/v4l2-dev.h
+++ b/include/media/v4l2-dev.h
@@ -32,6 +32,7 @@ struct v4l2_device;
Drivers can clear this flag if they want to block all future
device access. It is cleared by video_unregister_device. */
#define V4L2_FL_REGISTERED (0)
+#define V4L2_FL_USES_V4L2_FH (1)
struct v4l2_file_operations {
struct module *owner;
@@ -77,6 +78,10 @@ struct video_device
/* attribute to differentiate multiple indices on one physical device */
int index;
+ /* V4L2 file handles */
+ spinlock_t fh_lock; /* Lock for all v4l2_fhs */
+ struct list_head fh_list; /* List of struct v4l2_fh */
+
int debug; /* Activates debug level*/
/* Video standard vars */
diff --git a/include/media/v4l2-fh.h b/include/media/v4l2-fh.h
new file mode 100644
index 0000000..6b486aa
--- /dev/null
+++ b/include/media/v4l2-fh.h
@@ -0,0 +1,42 @@
+/*
+ * include/media/v4l2-fh.h
+ *
+ * V4L2 file handle.
+ *
+ * Copyright (C) 2009 Nokia Corporation.
+ *
+ * Contact: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxxxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#ifndef V4L2_FH_H
+#define V4L2_FH_H
+
+#include <linux/list.h>
+
+struct video_device;
+
+struct v4l2_fh {
+ struct list_head list;
+ struct video_device *vdev;
+};
+
+void v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev);
+void v4l2_fh_add(struct v4l2_fh *fh);
+void v4l2_fh_del(struct v4l2_fh *fh);
+void v4l2_fh_exit(struct v4l2_fh *fh);
+
+#endif /* V4L2_EVENT_H */
--
1.5.6.5
--
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