On 10/16/19 4:55 PM, Ricardo Ribalda Delgado wrote:
> This allows setting the default value on compound controls created via
> v4l2_ctrl_new_custom.
>
> Signed-off-by: Ricardo Ribalda Delgado <ribalda@xxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-ctrls.c | 3 ++-
> include/media/v4l2-ctrls.h | 2 ++
> 2 files changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
> index bf50d37ef6c1..939aa110daa0 100644
> --- a/drivers/media/v4l2-core/v4l2-ctrls.c
> +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
> @@ -2583,7 +2583,8 @@ struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
> type, min, max,
> is_menu ? cfg->menu_skip_mask : step, def,
> cfg->dims, cfg->elem_size,
> - flags, qmenu, qmenu_int, ptr_null, priv);
> + flags, qmenu, qmenu_int,
> + v4l2_ctrl_ptr_create((void *)cfg->p_def), priv);
I don't like this cast. I've been experimenting a bit and this works fine:
#include <stdlib.h>
#include <stdio.h>
union v4l2_ctrl_ptr {
int *p_int;
const int *p_int_const;
};
struct v4l2_ctrl_config {
union v4l2_ctrl_ptr p;
};
static const int i = 5;
static const struct v4l2_ctrl_config c = {
.p.p_int_const = &i,
};
int main(int argc, char **argv)
{
printf("%d\n", *c.p.p_int_const);
return 0;
}
So I would like to see a p_const being added to the union, and I think we
need a v4l2_ctrl_const_ptr_create() helper.
In a separate patch it would be really nice to replace any uses of .p with
.p_const where possible to signal that the contents isn't modified.
Regards,
Hans
> if (ctrl)
> ctrl->is_private = cfg->is_private;
> return ctrl;
> diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
> index 26205ba3a0a0..d08d19a4ae34 100644
> --- a/include/media/v4l2-ctrls.h
> +++ b/include/media/v4l2-ctrls.h
> @@ -375,6 +375,7 @@ struct v4l2_ctrl_handler {
> * @max: The control's maximum value.
> * @step: The control's step value for non-menu controls.
> * @def: The control's default value.
> + * @p_def: The control's default value for compound controls.
> * @dims: The size of each dimension.
> * @elem_size: The size in bytes of the control.
> * @flags: The control's flags.
> @@ -403,6 +404,7 @@ struct v4l2_ctrl_config {
> s64 max;
> u64 step;
> s64 def;
> + const void *p_def;
> u32 dims[V4L2_CTRL_MAX_DIMS];
> u32 elem_size;
> u32 flags;
>
