printk: Fix return of braille_register_console()

Some of my configs I test with have CONFIG_A11Y_BRAILLE_CONSOLE set.
When I started testing against v3.11-rc4 my console went bonkers.  Using
ktest to bisect the issue, it came down to:

commit 3b697c92c "printk: move braille console support into separate
braille.[ch] files"

Looking into the patch I found the problem.  It's with the return of
braille_register_console().  As anything other than NULL is considered a
failure.

But for those of us that have CONFIG_A11Y_BRAILLE_CONSOLE set but do not
define a "brl" or "brl=" on the command line, we still may want a
console that those with sight can still use.

Return NULL (success) if "brl" or "brl=" is not on the console line.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/kernel/printk/braille.c b/kernel/printk/braille.c
index b51087fb9acec5a33d8ee53b37206b7fdbd770b1..276762f3a46078141117e5810c1afc964e869ec9 100644 (file)
--- a/kernel/printk/braille.c
+++ b/kernel/printk/braille.c
@@ -19,7 +19,8 @@ char *_braille_console_setup(char **str, char **brl_options)
                        pr_err("need port name after brl=\n");
                else
                        *((*str)++) = 0;
-       }
+       } else
+               return NULL;
 
        return *str;
 }