Add a new function to modify the dimensions of an array control.
This is typically used if the array size depends on e.g. the currently
selected video format.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-ctrls-api.c | 36 ++++++++++++++++
include/media/v4l2-ctrls.h | 53 ++++++++++++++++++++++++
2 files changed, 89 insertions(+)
diff --git a/drivers/media/v4l2-core/v4l2-ctrls-api.c b/drivers/media/v4l2-core/v4l2-ctrls-api.c
index 6f1b72c59e8e..878da8592106 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls-api.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls-api.c
@@ -989,6 +989,42 @@ int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
}
EXPORT_SYMBOL(__v4l2_ctrl_modify_range);
+int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
+ u32 dims[V4L2_CTRL_MAX_DIMS])
+{
+ unsigned int elems = 1;
+ unsigned int i;
+ void *p_array;
+
+ lockdep_assert_held(ctrl->handler->lock);
+
+ if (!ctrl->is_array || ctrl->is_dyn_array)
+ return -EINVAL;
+
+ for (i = 0; i < ctrl->nr_of_dims; i++)
+ elems *= dims[i];
+ if (elems == 0)
+ return -EINVAL;
+ p_array = kvzalloc(2 * elems * ctrl->elem_size, GFP_KERNEL);
+ if (!p_array)
+ return -ENOMEM;
+ kvfree(ctrl->p_array);
+ ctrl->p_array_alloc_elems = elems;
+ ctrl->elems = elems;
+ ctrl->new_elems = elems;
+ ctrl->p_array = p_array;
+ ctrl->p_new.p = p_array;
+ ctrl->p_cur.p = p_array + elems * ctrl->elem_size;
+ for (i = 0; i < ctrl->nr_of_dims; i++)
+ ctrl->dims[i] = dims[i];
+ for (i = 0; i < elems; i++)
+ ctrl->type_ops->init(ctrl, i, ctrl->p_cur);
+ cur_to_new(ctrl);
+ send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_VALUE);
+ return 0;
+}
+EXPORT_SYMBOL(__v4l2_ctrl_modify_dimensions);
+
/* Implement VIDIOC_QUERY_EXT_CTRL */
int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_query_ext_ctrl *qc)
{
diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
index e0f32e8b886a..683e9903a6ea 100644
--- a/include/media/v4l2-ctrls.h
+++ b/include/media/v4l2-ctrls.h
@@ -963,6 +963,59 @@ static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl,
return rval;
}
+/**
+ *__v4l2_ctrl_modify_dimensions() - Unlocked variant of v4l2_ctrl_modify_dimensions()
+ *
+ * @ctrl: The control to update.
+ * @dims: The control's new dimensions.
+ *
+ * Update the dimensions of an array control on the fly. The elements of the
+ * array are reset to their default value, even if the dimensions are
+ * unchanged.
+ *
+ * An error is returned if @dims is invalid for this control.
+ *
+ * The caller is responsible for acquiring the control handler mutex on behalf
+ * of __v4l2_ctrl_modify_dimensions().
+ *
+ * Note: calling this function when the same control is used in pending requests
+ * is untested. It should work (a request with the wrong size of the control
+ * will drop that control silently), but it will be very confusing.
+ */
+int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
+ u32 dims[V4L2_CTRL_MAX_DIMS]);
+
+/**
+ * v4l2_ctrl_modify_dimensions() - Update the dimensions of an array control.
+ *
+ * @ctrl: The control to update.
+ * @dims: The control's new dimensions.
+ *
+ * Update the dimensions of an array control on the fly. The elements of the
+ * array are reset to their default value, even if the dimensions are
+ * unchanged.
+ *
+ * An error is returned if @dims is invalid for this control type.
+ *
+ * This function assumes that the control handler is not locked and will
+ * take the lock itself.
+ *
+ * Note: calling this function when the same control is used in pending requests
+ * is untested. It should work (a request with the wrong size of the control
+ * will drop that control silently), but it will be very confusing.
+ */
+static inline int v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,
+ u32 dims[V4L2_CTRL_MAX_DIMS])
+{
+ int rval;
+
+ v4l2_ctrl_lock(ctrl);
+ rval = __v4l2_ctrl_modify_dimensions(ctrl, dims);
+ v4l2_ctrl_unlock(ctrl);
+
+ return rval;
+}
+
/**
* v4l2_ctrl_notify() - Function to set a notify callback for a control.
*
--
2.35.1
