[media] v4l2: use new flag to enable core priority handling

Rather than guess which driver supports core priority handling, require drivers
that do to explicitly set the V4L2_FL_USE_FH_PRIO flag in video_device.

Updated the core prio handling accordingly and set the flag in the three
drivers that do.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans Verkuil 2011-03-22 10:14:07 -03:00 committed by Mauro Carvalho Chehab
parent 2f82441a86
commit b1a873a37b
8 changed files with 27 additions and 14 deletions

View file

@ -577,6 +577,10 @@ You should also set these fields:
(cx8802). Since the v4l2_device cannot be associated with a particular
PCI device it is setup without a parent device. But when the struct
video_device is setup you do know which parent PCI device to use.
- flags: optional. Set to V4L2_FL_USE_FH_PRIO if you want to let the framework
handle the VIDIOC_G/S_PRIORITY ioctls. This requires that you use struct
v4l2_fh. Eventually this flag will disappear once all drivers use the core
priority handling. But for now it has to be set explicitly.
If you use v4l2_ioctl_ops, then you should set .unlocked_ioctl to video_ioctl2
in your v4l2_file_operations struct.
@ -775,7 +779,8 @@ struct v4l2_fh
struct v4l2_fh provides a way to easily keep file handle specific data
that is used by the V4L2 framework. New drivers must use struct v4l2_fh
since it is also used to implement priority handling (VIDIOC_G/S_PRIORITY).
since it is also used to implement priority handling (VIDIOC_G/S_PRIORITY)
if the video_device flag V4L2_FL_USE_FH_PRIO is also set.
The users of v4l2_fh (in the V4L2 framework, not the driver) know
whether a driver uses v4l2_fh as its file->private_data pointer by

View file

@ -207,6 +207,7 @@ static int cx18_prep_dev(struct cx18 *cx, int type)
s->video_dev->fops = &cx18_v4l2_enc_fops;
s->video_dev->release = video_device_release;
s->video_dev->tvnorms = V4L2_STD_ALL;
set_bit(V4L2_FL_USE_FH_PRIO, &s->video_dev->flags);
cx18_set_funcs(s->video_dev);
return 0;
}

View file

@ -214,6 +214,7 @@ static int ivtv_prep_dev(struct ivtv *itv, int type)
s->vdev->fops = ivtv_stream_info[type].fops;
s->vdev->release = video_device_release;
s->vdev->tvnorms = V4L2_STD_ALL;
set_bit(V4L2_FL_USE_FH_PRIO, &s->vdev->flags);
ivtv_set_funcs(s->vdev);
return 0;
}

View file

@ -578,11 +578,9 @@ int __video_register_device(struct video_device *vdev, int type, int nr,
vdev->parent = vdev->v4l2_dev->dev;
if (vdev->ctrl_handler == NULL)
vdev->ctrl_handler = vdev->v4l2_dev->ctrl_handler;
/* If the prio state pointer is NULL, and if the driver doesn't
handle priorities itself, then use the v4l2_device prio
state. */
if (vdev->prio == NULL && vdev->ioctl_ops &&
vdev->ioctl_ops->vidioc_s_priority == NULL)
/* If the prio state pointer is NULL, then use the v4l2_device
prio state. */
if (vdev->prio == NULL)
vdev->prio = &vdev->v4l2_dev->prio;
}

View file

@ -35,7 +35,6 @@ int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
INIT_LIST_HEAD(&fh->list);
set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags);
fh->prio = V4L2_PRIORITY_UNSET;
BUG_ON(vdev->prio == NULL);
/*
* fh->events only needs to be initialized if the driver
@ -54,7 +53,8 @@ void v4l2_fh_add(struct v4l2_fh *fh)
{
unsigned long flags;
v4l2_prio_open(fh->vdev->prio, &fh->prio);
if (test_bit(V4L2_FL_USE_FH_PRIO, &fh->vdev->flags))
v4l2_prio_open(fh->vdev->prio, &fh->prio);
spin_lock_irqsave(&fh->vdev->fh_lock, flags);
list_add(&fh->list, &fh->vdev->fh_list);
spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
@ -82,7 +82,8 @@ void v4l2_fh_del(struct v4l2_fh *fh)
spin_lock_irqsave(&fh->vdev->fh_lock, flags);
list_del_init(&fh->list);
spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
v4l2_prio_close(fh->vdev->prio, fh->prio);
if (test_bit(V4L2_FL_USE_FH_PRIO, &fh->vdev->flags))
v4l2_prio_close(fh->vdev->prio, fh->prio);
}
EXPORT_SYMBOL_GPL(v4l2_fh_del);

View file

@ -541,6 +541,7 @@ static long __video_do_ioctl(struct file *file,
void *fh = file->private_data;
struct v4l2_fh *vfh = NULL;
struct v4l2_format f_copy;
int use_fh_prio = 0;
long ret = -EINVAL;
if (ops == NULL) {
@ -555,10 +556,12 @@ static long __video_do_ioctl(struct file *file,
printk(KERN_CONT "\n");
}
if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags))
if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
vfh = file->private_data;
use_fh_prio = test_bit(V4L2_FL_USE_FH_PRIO, &vfd->flags);
}
if (vfh && !ops->vidioc_s_priority) {
if (use_fh_prio) {
switch (cmd) {
case VIDIOC_S_CTRL:
case VIDIOC_S_STD:
@ -620,7 +623,7 @@ static long __video_do_ioctl(struct file *file,
if (ops->vidioc_g_priority) {
ret = ops->vidioc_g_priority(file, fh, p);
} else if (vfh) {
} else if (use_fh_prio) {
*p = v4l2_prio_max(&vfd->v4l2_dev->prio);
ret = 0;
}
@ -632,7 +635,7 @@ static long __video_do_ioctl(struct file *file,
{
enum v4l2_priority *p = arg;
if (!ops->vidioc_s_priority && vfh == NULL)
if (!ops->vidioc_s_priority && !use_fh_prio)
break;
dbgarg(cmd, "setting priority to %d\n", *p);
if (ops->vidioc_s_priority)
@ -2187,7 +2190,7 @@ static long __video_do_ioctl(struct file *file,
if (!ops->vidioc_default)
break;
if (vfh && !ops->vidioc_s_priority)
if (use_fh_prio)
valid_prio = v4l2_prio_check(vfd->prio, vfh->prio) >= 0;
ret = ops->vidioc_default(file, fh, valid_prio, cmd, arg);
break;

View file

@ -1254,6 +1254,7 @@ static int __init vivi_create_instance(int inst)
*vfd = vivi_template;
vfd->debug = debug;
vfd->v4l2_dev = &dev->v4l2_dev;
set_bit(V4L2_FL_USE_FH_PRIO, &vfd->flags);
/*
* Provide a mutex to v4l2 core. It will be used to protect

View file

@ -35,7 +35,10 @@ struct v4l2_ctrl_handler;
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)
/* file->private_data points to struct v4l2_fh */
#define V4L2_FL_USES_V4L2_FH (1)
/* Use the prio field of v4l2_fh for core priority checking */
#define V4L2_FL_USE_FH_PRIO (2)
/* Priority helper functions */