[media] media: v4l2-ctrl: add a helper function to add standard control with driver specific menu

Add helper function v4l2_ctrl_new_std_menu_items(), which adds
a standard menu control, with driver specific menu.

Signed-off-by: Lad, Prabhakar <prabhakar.lad@ti.com>
Signed-off-by: Manjunath Hadli <manjunath.hadli@ti.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/Documentation/video4linux/v4l2-controls.txt b/Documentation/video4linux/v4l2-controls.txt
index 54270df99d5c..cfe52c798d74 100644
--- a/Documentation/video4linux/v4l2-controls.txt
+++ b/Documentation/video4linux/v4l2-controls.txt
@@ -136,11 +136,25 @@ Or alternatively for integer menu controls, by calling v4l2_ctrl_new_int_menu:
                         const struct v4l2_ctrl_ops *ops,
                         u32 id, s32 max, s32 def, const s64 *qmenu_int);
 
+Standard menu controls with a driver specific menu are added by calling
+v4l2_ctrl_new_std_menu_items:
+
+        struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(
+                struct v4l2_ctrl_handler *hdl,
+                const struct v4l2_ctrl_ops *ops, u32 id, s32 max,
+                s32 skip_mask, s32 def, const char * const *qmenu);
+
 These functions are typically called right after the v4l2_ctrl_handler_init:
 
         static const s64 exp_bias_qmenu[] = {
                -2, -1, 0, 1, 2
         };
+        static const char * const test_pattern[] = {
+                "Disabled",
+                "Vertical Bars",
+                "Solid Black",
+                "Solid White",
+        };
 
         v4l2_ctrl_handler_init(&foo->ctrl_handler, nr_of_controls);
         v4l2_ctrl_new_std(&foo->ctrl_handler, &foo_ctrl_ops,
@@ -156,6 +170,9 @@ These functions are typically called right after the v4l2_ctrl_handler_init:
                         ARRAY_SIZE(exp_bias_qmenu) - 1,
                         ARRAY_SIZE(exp_bias_qmenu) / 2 - 1,
                         exp_bias_qmenu);
+        v4l2_ctrl_new_std_menu_items(&foo->ctrl_handler, &foo_ctrl_ops,
+                        V4L2_CID_TEST_PATTERN, ARRAY_SIZE(test_pattern) - 1, 0,
+                        0, test_pattern);
         ...
         if (foo->ctrl_handler.error) {
                 int err = foo->ctrl_handler.error;
@@ -185,6 +202,13 @@ 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.
 
+The v4l2_ctrl_new_std_menu_items function is very similar to
+v4l2_ctrl_new_std_menu but takes an extra parameter qmenu, which is the driver
+specific menu for an otherwise standard menu control. A good example for this
+control is the test pattern control for capture/display/sensors devices that
+have the capability to generate test patterns. These test patterns are hardware
+specific, so the contents of the menu will vary from device to device.
+
 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