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-rw-r--r--Documentation/video4linux/v4l2-controls.txt21
1 files changed, 21 insertions, 0 deletions
diff --git a/Documentation/video4linux/v4l2-controls.txt b/Documentation/video4linux/v4l2-controls.txt
index e2492a9..43da22b 100644
--- a/Documentation/video4linux/v4l2-controls.txt
+++ b/Documentation/video4linux/v4l2-controls.txt
@@ -130,8 +130,18 @@ Menu controls are added by calling v4l2_ctrl_new_std_menu:
const struct v4l2_ctrl_ops *ops,
u32 id, s32 max, s32 skip_mask, s32 def);
+Or alternatively for integer menu controls, by calling v4l2_ctrl_new_int_menu:
+
+ struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
+ const struct v4l2_ctrl_ops *ops,
+ u32 id, s32 max, s32 def, const s64 *qmenu_int);
+
These functions are typically called right after the v4l2_ctrl_handler_init:
+ static const s64 exp_bias_qmenu[] = {
+ -2, -1, 0, 1, 2
+ };
+
v4l2_ctrl_handler_init(&foo->ctrl_handler, nr_of_controls);
v4l2_ctrl_new_std(&foo->ctrl_handler, &foo_ctrl_ops,
V4L2_CID_BRIGHTNESS, 0, 255, 1, 128);
@@ -141,6 +151,11 @@ These functions are typically called right after the v4l2_ctrl_handler_init:
V4L2_CID_POWER_LINE_FREQUENCY,
V4L2_CID_POWER_LINE_FREQUENCY_60HZ, 0,
V4L2_CID_POWER_LINE_FREQUENCY_DISABLED);
+ v4l2_ctrl_new_int_menu(&foo->ctrl_handler, &foo_ctrl_ops,
+ V4L2_CID_EXPOSURE_BIAS,
+ ARRAY_SIZE(exp_bias_qmenu) - 1,
+ ARRAY_SIZE(exp_bias_qmenu) / 2 - 1,
+ exp_bias_qmenu);
...
if (foo->ctrl_handler.error) {
int err = foo->ctrl_handler.error;
@@ -164,6 +179,12 @@ controls. There is no min argument since that is always 0 for menu controls,
and instead of a step there is a skip_mask argument: if bit X is 1, then menu
item X is skipped.
+The v4l2_ctrl_new_int_menu function creates a new standard integer menu
+control with driver-specific items in the menu. It differs from
+v4l2_ctrl_new_std_menu in that it doesn't have the mask argument and takes
+as the last argument an array of signed 64-bit integers that form an exact
+menu item list.
+
Note that if something fails, the function will return NULL or an error and
set ctrl_handler->error to the error code. If ctrl_handler->error was already
set, then it will just return and do nothing. This is also true for