2017-03-26 20:57:13

by Samuel Thibault

Subject: [PATCHv2] braille-console: Fix value returned by _braille_console_setup

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 <[email protected]>
Cc: Aleksey Makarov <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: Ming Lei <[email protected]>
Cc: Steven Rostedt <[email protected]>
Acked-by: Petr Mladek <[email protected]>
---
new in v2:
- drop now-useless else

Index: linux-4.10/kernel/printk/braille.c
===================================================================
--- linux-4.10.orig/kernel/printk/braille.c
+++ linux-4.10/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
Index: linux-4.10/kernel/printk/braille.h
===================================================================
--- linux-4.10.orig/kernel/printk/braille.h
+++ linux-4.10/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

2017-03-27 15:45:08

by Sergey Senozhatsky

Subject: Re: [PATCHv2] braille-console: Fix value returned by _braille_console_setup

On (03/26/17 22:47), Samuel Thibault wrote:
> 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.

I just found this patch in my gmail "spam" folder.

sorry.


the patch looks OK to me.

btw, is there any reason why _braille_console_setup() and
_braille_register_console()/_braille_unregister_console()
names start with a dash? do we also want to "clean this up"?
well since we are at it.

-ss