[PATCH 03/54] gpio: em: Be sure to clamp return value

[PATCH 03/54] gpio: em: Be sure to clamp return value

[Linus Walleij]

As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.

Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Magnus Damm <damm@opensource.se>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/gpio/gpio-em.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-em.c b/drivers/gpio/gpio-em.c
index c3ca2b1c1dfe..d726c68c4a65 100644
--- a/drivers/gpio/gpio-em.c
+++ b/drivers/gpio/gpio-em.c
@@ -203,7 +203,7 @@ static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset)
 
 static int em_gio_get(struct gpio_chip *chip, unsigned offset)
 {
-	return (int)(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset));
+	return !!(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset));
 }
 
 static void __em_gio_set(struct gpio_chip *chip, unsigned int reg,
-- 
2.4.3

Re: [PATCH 03/54] gpio: em: Be sure to clamp return value

[Geert Uytterhoeven]

On Tue, Dec 22, 2015 at 3:11 PM, Linus Walleij <linus.walleij@linaro.org> wrote:
> As we want gpio_chip .get() calls to be able to return negative
> error codes and propagate to drivers, we need to go over all
> drivers and make sure their return values are clamped to [0,1].
> We do this by using the ret = !!(val) design pattern.
>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Cc: Magnus Damm <damm@opensource.se>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds