Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1300005 > unrolled thread

[PATCH] gpiolib: always initialize *flags from of_get_named_gpio_flags

Started byArnd Bergmann <arnd@arndb.de>
First post2016-01-01 23:50 +0100
Last post2016-01-04 08:50 +0100
Articles 2 — 2 participants

Back to article view | Back to linux.kernel


Contents

  [PATCH] gpiolib: always initialize *flags from of_get_named_gpio_flags Arnd Bergmann <arnd@arndb.de> - 2016-01-01 23:50 +0100
    Re: [PATCH] gpiolib: always initialize *flags from of_get_named_gpio_flags Linus Walleij <linus.walleij@linaro.org> - 2016-01-04 08:50 +0100

#1300005 — [PATCH] gpiolib: always initialize *flags from of_get_named_gpio_flags

FromArnd Bergmann <arnd@arndb.de>
Date2016-01-01 23:50 +0100
Subject[PATCH] gpiolib: always initialize *flags from of_get_named_gpio_flags
Message-ID<qMgGd-8od-5@gated-at.bofh.it>
The of_get_named_gpio_flags() function does nothing other than returning
an error when CONFIG_OF_GPIO is disabled, but that causes spurious
warnings about possible use of uninitialized variables in any code that
does not check the of_get_named_gpio_flags() return value before trying
to use the flags:

drivers/input/misc/rotary_encoder.c: In function 'rotary_encoder_probe':
drivers/input/misc/rotary_encoder.c:223:28: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
drivers/power/bq24735-charger.c: In function 'bq24735_charger_probe':
drivers/power/bq24735-charger.c:227:12: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
drivers/power/sbs-battery.c: In function 'sbs_probe':
drivers/power/sbs-battery.c:782:17: warning: 'gpio_flags' may be used uninitialized in this function [-Wmaybe-uninitialized]

This changes the behavior of the inline helper to set the flags to zero
when OF_GPIO is disabled, to avoid the warnings. In all cases I've
encountered, we don't actually get to the place that uses the flags
if CONFIG_OF is disabled because we won't enter the DT parser code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h
index 87d6d1632dd4..bb85a8eeba6a 100644
--- a/include/linux/of_gpio.h
+++ b/include/linux/of_gpio.h
@@ -67,6 +67,9 @@ extern int of_gpio_simple_xlate(struct gpio_chip *gc,
 static inline int of_get_named_gpio_flags(struct device_node *np,
 		const char *list_name, int index, enum of_gpio_flags *flags)
 {
+	if (flags)
+		*flags = 0;
+
 	return -ENOSYS;
 }
 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [next] | [standalone]


#1300524

FromLinus Walleij <linus.walleij@linaro.org>
Date2016-01-04 08:50 +0100
Message-ID<qN83T-op-1@gated-at.bofh.it>
In reply to#1300005
On Fri, Jan 1, 2016 at 11:40 PM, Arnd Bergmann <arnd@arndb.de> wrote:

> The of_get_named_gpio_flags() function does nothing other than returning
> an error when CONFIG_OF_GPIO is disabled, but that causes spurious
> warnings about possible use of uninitialized variables in any code that
> does not check the of_get_named_gpio_flags() return value before trying
> to use the flags:
>
> drivers/input/misc/rotary_encoder.c: In function 'rotary_encoder_probe':
> drivers/input/misc/rotary_encoder.c:223:28: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
> drivers/power/bq24735-charger.c: In function 'bq24735_charger_probe':
> drivers/power/bq24735-charger.c:227:12: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
> drivers/power/sbs-battery.c: In function 'sbs_probe':
> drivers/power/sbs-battery.c:782:17: warning: 'gpio_flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
>
> This changes the behavior of the inline helper to set the flags to zero
> when OF_GPIO is disabled, to avoid the warnings. In all cases I've
> encountered, we don't actually get to the place that uses the flags
> if CONFIG_OF is disabled because we won't enter the DT parser code.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Patch applied!

Yours,
Linus Walleij
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[toc] | [prev] | [standalone]


Back to top | Article view | linux.kernel


csiph-web