menuconfig: add support to show hidden options which have prompts

Usage:
  Press <Z> to show all config symbols which have prompts.

Quote Tim Bird:

| I've been bitten by this numerous times.  I most often
| use ftrace on ARM, but when I go back to x86, I almost
| always go through a sequence of searching for the
| function graph tracer in the menus, then realizing it's
| completely missing until I disable CC_OPTIMIZE_FOR_SIZE.
|
| Is there any way to have the menu item appear, but be
| unsettable unless the SIZE option is disabled?  I'm
| not a Kconfig guru...

I myself found this useful too. For example, I need to test
ftrace/tracing and want to be sure all the tracing features are
enabled, so I  enter the "Tracers" menu, and press <Z> to
see if there is any config hidden.

I also noticed gconfig and xconfig have a button "Show all options",
but that's a bit too much, and I think normally what we are not
interested in those configs which have no prompt thus can't be
changed by users.

Exmaple:

      --- Tracers
      -*-   Kernel Function Tracer
      - -     Kernel Function Graph Tracer
      [*]   Interrupts-off Latency Tracer
      - -   Preemption-off Latency Tracer
      [*]   Sysprof Tracer

Here you can see 2 tracers are not selectable, and then can find
out how to make them selectable.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>

1 files changed, 10 insertions, 0 deletions

diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
index 62e3f15ede0..203632cc30b 100644
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -390,6 +390,13 @@ void menu_finalize(struct menu *parent)
 	}
 }
 
+bool menu_has_prompt(struct menu *menu)
+{
+	if (!menu->prompt)
+		return false;
+	return true;
+}
+
 bool menu_is_visible(struct menu *menu)
 {
 	struct menu *child;
@@ -398,6 +405,7 @@ bool menu_is_visible(struct menu *menu)
 
 	if (!menu->prompt)
 		return false;
+
 	sym = menu->sym;
 	if (sym) {
 		sym_calc_value(sym);
@@ -407,12 +415,14 @@ bool menu_is_visible(struct menu *menu)
 
 	if (visible != no)
 		return true;
+
 	if (!sym || sym_get_tristate_value(menu->sym) == no)
 		return false;
 
 	for (child = menu->list; child; child = child->next)
 		if (menu_is_visible(child))
 			return true;
+
 	return false;
 }