[04/54] gpio: ich: Be sure to clamp return value

Message ID 1450793493-21995-1-git-send-email-linus.walleij@linaro.org
State New
Headers show

Commit Message

Linus Walleij Dec. 22, 2015, 2:11 p.m.
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: Aaron Sierra <asierra@xes-inc.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

---
 drivers/gpio/gpio-ich.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

-- 
2.4.3

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Comments

Linus Walleij Dec. 25, 2015, 12:43 p.m. | #1
On Wed, Dec 23, 2015 at 5:59 PM, Aaron Sierra <asierra@xes-inc.com> wrote:

>> -             return (data >> 16) & (1 << nr) ? 1 : 0;

>> +             return !!((data >> 16) & (1 << nr));

>

> Linus,

> Is this particular change done to simplify verification via Coccinelle? Otherwise,

> this value is already clamped to 0/1.


No this was my manual inspection, which isn't very accurate. When
in doubt, I made a patch. I'll drop this then, thanks!

Yours,
Linus Walleij
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Patch

diff --git a/drivers/gpio/gpio-ich.c b/drivers/gpio/gpio-ich.c
index 8623d12e23c1..68e525a3cea3 100644
--- a/drivers/gpio/gpio-ich.c
+++ b/drivers/gpio/gpio-ich.c
@@ -236,9 +236,9 @@  static int ich6_gpio_get(struct gpio_chip *chip, unsigned nr)
 
 		spin_unlock_irqrestore(&ichx_priv.lock, flags);
 
-		return (data >> 16) & (1 << nr) ? 1 : 0;
+		return !!((data >> 16) & (1 << nr));
 	} else {
-		return ichx_gpio_get(chip, nr);
+		return !!ichx_gpio_get(chip, nr);
 	}
 }