[PATCH v3 5/7] media: v4l2-core: Add new helper for area controls

[Ricardo Ribalda Delgado <ribalda@kernel.org>]

Adding a V4L2_CID_UNIT_CELL_SIZE control requires a lot of boilerplate,
try to minimize it by adding a new helper.

Suggested-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Ricardo Ribalda Delgado <ribalda@kernel.org>
---
 drivers/media/v4l2-core/v4l2-ctrls.c | 25 ++++++++++++++++++++++++-
 include/media/v4l2-ctrls.h           | 16 ++++++++++++++++
 2 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index b3bf458df7f7..33e48f0aec1a 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -2660,7 +2660,6 @@ struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
 }
 EXPORT_SYMBOL(v4l2_ctrl_new_std_menu_items);
 
-/* Helper function for standard integer menu controls */
 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
 			const struct v4l2_ctrl_ops *ops,
 			u32 id, u8 _max, u8 _def, const s64 *qmenu_int)
@@ -2684,6 +2683,30 @@ struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
 }
 EXPORT_SYMBOL(v4l2_ctrl_new_int_menu);
 
+static void area_init(const struct v4l2_ctrl *ctrl, u32 idx,
+		union v4l2_ctrl_ptr ptr)
+{
+	memcpy(ptr.p_area, ctrl->priv, sizeof(*ptr.p_area));
+}
+
+static const struct v4l2_ctrl_type_ops area_ops = {
+	.init = area_init,
+};
+
+struct v4l2_ctrl *v4l2_ctrl_new_area(struct v4l2_ctrl_handler *hdl,
+				     const struct v4l2_ctrl_ops *ops,
+				     u32 id, const struct v4l2_area *area)
+{
+	static struct v4l2_ctrl_config ctrl = {
+		.id = V4L2_CID_UNIT_CELL_SIZE,
+		.type_ops = &area_ops,
+	};
+
+	return v4l2_ctrl_new_custom(hdl, &ctrl, (void *)area);
+}
+EXPORT_SYMBOL(v4l2_ctrl_new_area);
+
+/* Helper function for standard integer menu controls */
 /* Add the controls from another handler to our own. */
 int v4l2_ctrl_add_handler(struct v4l2_ctrl_handler *hdl,
 			  struct v4l2_ctrl_handler *add,
diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
index 9a3d11350e67..36f0712ea6dd 100644
--- a/include/media/v4l2-ctrls.h
+++ b/include/media/v4l2-ctrls.h
@@ -669,6 +669,22 @@ struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
 					 u32 id, u8 max, u8 def,
 					 const s64 *qmenu_int);
 
+/**
+ * v4l2_ctrl_new_area() - Allocate and initialize a V4L2_CTRL_TYPE_AREA control.
+ *
+ * @hdl:	The control handler.
+ * @ops:	The control ops.
+ * @id:	The control ID.
+ * @area:	The width and height of the area in a struct v4l2_area.
+ *
+ * If the &v4l2_ctrl struct could not be allocated then NULL is returned
+ * and @hdl->error is set to the error code (if it wasn't set already).
+ */
+
+struct v4l2_ctrl *v4l2_ctrl_new_area(struct v4l2_ctrl_handler *hdl,
+				     const struct v4l2_ctrl_ops *ops,
+				     u32 id, const struct v4l2_area *area);
+
 /**
  * typedef v4l2_ctrl_filter - Typedef to define the filter function to be
  *	used when adding a control handler.
-- 
2.23.0.rc1