V4L/DVB (8637): v4l2: add v4l2_ctrl_query_menu_valid_items support function

v4l2_ctrl_query_menu_valid_items() makes it easy to handle control menus
that have a lot of invalid 'holes'. For example, many MPEG encoders only
support a limited subset of audio bitrates. In that case a driver can
specify an array listing the set of valid bitrates and pass that to
this function.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans Verkuil 2008-08-08 08:34:19 -03:00 committed by Mauro Carvalho Chehab
parent 69028d7096
commit 1e55126666
2 changed files with 24 additions and 1 deletions

View File

@ -643,6 +643,7 @@ int v4l2_ctrl_query_menu(struct v4l2_querymenu *qmenu, struct v4l2_queryctrl *qc
{
int i;
qmenu->reserved = 0;
if (menu_items == NULL ||
(qctrl && (qmenu->index < qctrl->minimum || qmenu->index > qctrl->maximum)))
return -EINVAL;
@ -650,11 +651,31 @@ int v4l2_ctrl_query_menu(struct v4l2_querymenu *qmenu, struct v4l2_queryctrl *qc
if (menu_items[i] == NULL || menu_items[i][0] == '\0')
return -EINVAL;
snprintf(qmenu->name, sizeof(qmenu->name), menu_items[qmenu->index]);
qmenu->reserved = 0;
return 0;
}
EXPORT_SYMBOL(v4l2_ctrl_query_menu);
/* Fill in a struct v4l2_querymenu based on the specified array of valid
menu items (terminated by V4L2_CTRL_MENU_IDS_END).
Use this if there are 'holes' in the list of valid menu items. */
int v4l2_ctrl_query_menu_valid_items(struct v4l2_querymenu *qmenu, const u32 *ids)
{
const char **menu_items = v4l2_ctrl_get_menu(qmenu->id);
qmenu->reserved = 0;
if (menu_items == NULL || ids == NULL)
return -EINVAL;
while (*ids != V4L2_CTRL_MENU_IDS_END) {
if (*ids++ == qmenu->index) {
snprintf(qmenu->name, sizeof(qmenu->name),
menu_items[qmenu->index]);
return 0;
}
}
return -EINVAL;
}
EXPORT_SYMBOL(v4l2_ctrl_query_menu_valid_items);
/* ctrl_classes points to an array of u32 pointers, the last element is
a NULL pointer. Each u32 array is a 0-terminated array of control IDs.
Each array must be sorted low to high and belong to the same control

View File

@ -82,6 +82,8 @@ int v4l2_ctrl_query_fill(struct v4l2_queryctrl *qctrl, s32 min, s32 max, s32 ste
int v4l2_ctrl_query_fill_std(struct v4l2_queryctrl *qctrl);
int v4l2_ctrl_query_menu(struct v4l2_querymenu *qmenu,
struct v4l2_queryctrl *qctrl, const char **menu_items);
#define V4L2_CTRL_MENU_IDS_END (0xffffffff)
int v4l2_ctrl_query_menu_valid_items(struct v4l2_querymenu *qmenu, const u32 *ids);
u32 v4l2_ctrl_next(const u32 * const *ctrl_classes, u32 id);
/* ------------------------------------------------------------------------- */