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Robert Jarzmik authored
The commit 9bf448c6 ("ARM: pxa: use generic gpio operation instead of gpio register") from Oct 17, 2011, leads to the following static checker warning: arch/arm/mach-pxa/spitz_pm.c:172 spitz_charger_wakeup() warn: double left shift '!gpio_get_value(SPITZ_GPIO_KEY_INT) << (1 << ((SPITZ_GPIO_KEY_INT) & 31))' As Dan reported, the value is shifted three times : - once by gpio_get_value(), which returns either 0 or BIT(gpio) - once by the shift operation '<<' - a last time by GPIO_bit(gpio) which is BIT(gpio) Therefore the calculation lead to a chained or operator of : - (1 << gpio) << (1 << gpio) = (2^gpio)^gpio = 2 ^ (gpio * gpio) It is be sheer luck the former statement works, only because each gpio used is strictly smaller than 6, and therefore 2^(gpio^2) never overflows a 32 bits value, and because it is used as a boolean value to check a gpio activation. As the xxx_charger_wakeup() functions are used as a true/false detection mechanism, take that opportunity to change their prototypes from integer return value to boolean one. Fixes: 9bf448c6 ("ARM: pxa: use generic gpio operation instead of gpio register") Reported-by:
Dan Carpenter <dan.carpenter@oracle.com> Cc: Joe Perches <joe@perches.com> Signed-off-by:
Robert Jarzmik <robert.jarzmik@free.fr>
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