printk: move braille console support into separate braille.[ch] files

Create files with prototypes and static inlines for braille support.  Make
braille_console functions return 1 on success.

Corrected CONFIG_A11Y_BRAILLE_CONSOLE=n _braille_console_setup
return value to NULL.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 48 insertions, 0 deletions

diff --git a/kernel/printk/braille.c b/kernel/printk/braille.c
new file mode 100644
index 000000000000..b51087fb9ace
--- /dev/null
+++ b/kernel/printk/braille.c
@@ -0,0 +1,48 @@
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/console.h>
+#include <linux/string.h>
+
+#include "console_cmdline.h"
+#include "braille.h"
+
+char *_braille_console_setup(char **str, char **brl_options)
+{
+        if (!memcmp(*str, "brl,", 4)) {
+                *brl_options = "";
+                *str += 4;
+        } else if (!memcmp(str, "brl=", 4)) {
+                *brl_options = *str + 4;
+                *str = strchr(*brl_options, ',');
+                if (!*str)
+                        pr_err("need port name after brl=\n");
+                else
+                        *((*str)++) = 0;
+        }
+
+        return *str;
+}
+
+int
+_braille_register_console(struct console *console, struct console_cmdline *c)
+{
+        int rtn = 0;
+
+        if (c->brl_options) {
+                console->flags |= CON_BRL;
+                rtn = braille_register_console(console, c->index, c->options,
+                                               c->brl_options);
+        }
+
+        return rtn;
+}
+
+int
+_braille_unregister_console(struct console *console)
+{
+        if (console->flags & CON_BRL)
+                return braille_unregister_console(console);
+
+        return 0;
+}