[media] v4l2-ioctl.c: v4l2-ioctl: add debug and callback/offset functionality

Add the necessary plumbing to make it possible to replace the switch by a
table driven implementation.

The ioctls ops can either be called directly, or by calling a small function
that does some additional work if needed.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans Verkuil 2012-06-22 06:04:16 -03:00 committed by Mauro Carvalho Chehab
parent 27cd2aba17
commit 86748f35da

View File

@ -396,12 +396,22 @@ struct v4l2_ioctl_info {
unsigned int ioctl;
u32 flags;
const char * const name;
union {
u32 offset;
int (*func)(const struct v4l2_ioctl_ops *ops,
struct file *file, void *fh, void *p);
};
void (*debug)(const void *arg, bool write_only);
};
/* This control needs a priority check */
#define INFO_FL_PRIO (1 << 0)
/* This control can be valid if the filehandle passes a control handler. */
#define INFO_FL_CTRL (1 << 1)
/* This is a standard ioctl, no need for special code */
#define INFO_FL_STD (1 << 2)
/* This is ioctl has its own function */
#define INFO_FL_FUNC (1 << 3)
/* Zero struct from after the field to the end */
#define INFO_FL_CLEAR(v4l2_struct, field) \
((offsetof(struct v4l2_struct, field) + \
@ -414,6 +424,24 @@ struct v4l2_ioctl_info {
.name = #_ioctl, \
}
#define IOCTL_INFO_STD(_ioctl, _vidioc, _debug, _flags) \
[_IOC_NR(_ioctl)] = { \
.ioctl = _ioctl, \
.flags = _flags | INFO_FL_STD, \
.name = #_ioctl, \
.offset = offsetof(struct v4l2_ioctl_ops, _vidioc), \
.debug = _debug, \
}
#define IOCTL_INFO_FNC(_ioctl, _func, _debug, _flags) \
[_IOC_NR(_ioctl)] = { \
.ioctl = _ioctl, \
.flags = _flags | INFO_FL_FUNC, \
.name = #_ioctl, \
.func = _func, \
.debug = _debug, \
}
static struct v4l2_ioctl_info v4l2_ioctls[] = {
IOCTL_INFO(VIDIOC_QUERYCAP, 0),
IOCTL_INFO(VIDIOC_ENUM_FMT, INFO_FL_CLEAR(v4l2_fmtdesc, type)),
@ -512,7 +540,7 @@ bool v4l2_is_known_ioctl(unsigned int cmd)
external ioctl messages as well as internal V4L ioctl */
void v4l_printk_ioctl(unsigned int cmd)
{
char *dir, *type;
const char *dir, *type;
switch (_IOC_TYPE(cmd)) {
case 'd':
@ -523,10 +551,11 @@ void v4l_printk_ioctl(unsigned int cmd)
type = "v4l2";
break;
}
printk("%s", v4l2_ioctls[_IOC_NR(cmd)].name);
pr_cont("%s", v4l2_ioctls[_IOC_NR(cmd)].name);
return;
default:
type = "unknown";
break;
}
switch (_IOC_DIR(cmd)) {
@ -536,7 +565,7 @@ void v4l_printk_ioctl(unsigned int cmd)
case _IOC_READ | _IOC_WRITE: dir = "rw"; break;
default: dir = "*ERR*"; break;
}
printk("%s ioctl '%c', dir=%s, #%d (0x%08x)",
pr_cont("%s ioctl '%c', dir=%s, #%d (0x%08x)",
type, _IOC_TYPE(cmd), dir, _IOC_NR(cmd), cmd);
}
EXPORT_SYMBOL(v4l_printk_ioctl);
@ -546,6 +575,9 @@ static long __video_do_ioctl(struct file *file,
{
struct video_device *vfd = video_devdata(file);
const struct v4l2_ioctl_ops *ops = vfd->ioctl_ops;
bool write_only = false;
struct v4l2_ioctl_info default_info;
const struct v4l2_ioctl_info *info;
void *fh = file->private_data;
struct v4l2_fh *vfh = NULL;
int use_fh_prio = 0;
@ -563,23 +595,40 @@ static long __video_do_ioctl(struct file *file,
}
if (v4l2_is_known_ioctl(cmd)) {
struct v4l2_ioctl_info *info = &v4l2_ioctls[_IOC_NR(cmd)];
info = &v4l2_ioctls[_IOC_NR(cmd)];
if (!test_bit(_IOC_NR(cmd), vfd->valid_ioctls) &&
!((info->flags & INFO_FL_CTRL) && vfh && vfh->ctrl_handler))
return -ENOTTY;
goto done;
if (use_fh_prio && (info->flags & INFO_FL_PRIO)) {
ret = v4l2_prio_check(vfd->prio, vfh->prio);
if (ret)
return ret;
goto done;
}
} else {
default_info.ioctl = cmd;
default_info.flags = 0;
default_info.debug = NULL;
info = &default_info;
}
if ((vfd->debug & V4L2_DEBUG_IOCTL) &&
!(vfd->debug & V4L2_DEBUG_IOCTL_ARG)) {
write_only = _IOC_DIR(cmd) == _IOC_WRITE;
if (info->debug && write_only && vfd->debug > V4L2_DEBUG_IOCTL) {
v4l_print_ioctl(vfd->name, cmd);
printk(KERN_CONT "\n");
pr_cont(": ");
info->debug(arg, write_only);
}
if (info->flags & INFO_FL_STD) {
typedef int (*vidioc_op)(struct file *file, void *fh, void *p);
const void *p = vfd->ioctl_ops;
const vidioc_op *vidioc = p + info->offset;
ret = (*vidioc)(file, fh, arg);
goto done;
} else if (info->flags & INFO_FL_FUNC) {
ret = info->func(ops, file, fh, arg);
goto done;
}
switch (cmd) {
@ -2101,10 +2150,26 @@ static long __video_do_ioctl(struct file *file,
break;
} /* switch */
if (vfd->debug & V4L2_DEBUG_IOCTL_ARG) {
if (ret < 0) {
v4l_print_ioctl(vfd->name, cmd);
printk(KERN_CONT " error %ld\n", ret);
done:
if (vfd->debug) {
if (write_only && vfd->debug > V4L2_DEBUG_IOCTL) {
if (ret < 0)
printk(KERN_DEBUG "%s: error %ld\n",
video_device_node_name(vfd), ret);
return ret;
}
v4l_print_ioctl(vfd->name, cmd);
if (ret < 0)
pr_cont(": error %ld\n", ret);
else if (vfd->debug == V4L2_DEBUG_IOCTL)
pr_cont("\n");
else if (!info->debug)
return ret;
else if (_IOC_DIR(cmd) == _IOC_NONE)
info->debug(arg, write_only);
else {
pr_cont(": ");
info->debug(arg, write_only);
}
}