Patch "braille-console: Fix value returned by _braille_console_setup" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    braille-console: Fix value returned by _braille_console_setup

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     braille-console-fix-value-returned-by-_braille_console_setup.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Mon Mar 19 09:58:12 CET 2018
From: Samuel Thibault <samuel.thibault@ens-lyon.org>
Date: Sun, 26 Mar 2017 22:47:36 +0200
Subject: braille-console: Fix value returned by _braille_console_setup

From: Samuel Thibault <samuel.thibault@ens-lyon.org>


[ Upstream commit 2ed2b8621be2708c0f6d61fe9841e9ad8b9753f0 ]

commit bbeddf52adc1 ("printk: move braille console support into
separate braille.[ch] files") introduced _braille_console_setup()
to outline the braille initialization code.  There was however some
confusion over the value it was supposed to return. commit 2cfe6c4ac7ee
("printk: Fix return of braille_register_console()") tried to fix it
but failed to.

This fixes and documents the returned value according to the use
in printk.c: non-zero return means a parsing error, and thus this
console configuration should be ignored.

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Aleksey Makarov <aleksey.makarov@linaro.org>
Cc: Joe Perches <joe@perches.com>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 kernel/printk/braille.c |   15 ++++++++-------
 kernel/printk/braille.h |   13 ++++++++++---
 2 files changed, 18 insertions(+), 10 deletions(-)

--- a/kernel/printk/braille.c
+++ b/kernel/printk/braille.c
@@ -2,12 +2,13 @@
 
 #include <linux/kernel.h>
 #include <linux/console.h>
+#include <linux/errno.h>
 #include <linux/string.h>
 
 #include "console_cmdline.h"
 #include "braille.h"
 
-char *_braille_console_setup(char **str, char **brl_options)
+int _braille_console_setup(char **str, char **brl_options)
 {
 	if (!strncmp(*str, "brl,", 4)) {
 		*brl_options = "";
@@ -15,14 +16,14 @@ char *_braille_console_setup(char **str,
 	} else if (!strncmp(*str, "brl=", 4)) {
 		*brl_options = *str + 4;
 		*str = strchr(*brl_options, ',');
-		if (!*str)
+		if (!*str) {
 			pr_err("need port name after brl=\n");
-		else
-			*((*str)++) = 0;
-	} else
-		return NULL;
+			return -EINVAL;
+		}
+		*((*str)++) = 0;
+	}
 
-	return *str;
+	return 0;
 }
 
 int
--- a/kernel/printk/braille.h
+++ b/kernel/printk/braille.h
@@ -9,7 +9,14 @@ braille_set_options(struct console_cmdli
 	c->brl_options = brl_options;
 }
 
-char *
+/*
+ * Setup console according to braille options.
+ * Return -EINVAL on syntax error, 0 on success (or no braille option was
+ * actually given).
+ * Modifies str to point to the serial options
+ * Sets brl_options to the parsed braille options.
+ */
+int
 _braille_console_setup(char **str, char **brl_options);
 
 int
@@ -25,10 +32,10 @@ braille_set_options(struct console_cmdli
 {
 }
 
-static inline char *
+static inline int
 _braille_console_setup(char **str, char **brl_options)
 {
-	return NULL;
+	return 0;
 }
 
 static inline int


Patches currently in stable-queue which might be from samuel.thibault@ens-lyon.org are

queue-4.4/braille-console-fix-value-returned-by-_braille_console_setup.patch
queue-4.4/staging-speakup-replace-bug_on-with-warn_on.patch