gpio-timberdale: fix a potential wrapping issue

->last_ier is an unsigned long but the high bits can't be used int the
original code because the shift wraps.

Cc: stable@kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-timberdale.c b/drivers/gpio/gpio-timberdale.c
index 031c6ad..1a3e2b9 100644 (file)
--- a/drivers/gpio/gpio-timberdale.c
+++ b/drivers/gpio/gpio-timberdale.c
@@ -116,7 +116,7 @@ static void timbgpio_irq_disable(struct irq_data *d)
        unsigned long flags;
 
        spin_lock_irqsave(&tgpio->lock, flags);
-       tgpio->last_ier &= ~(1 << offset);
+       tgpio->last_ier &= ~(1UL << offset);
        iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
        spin_unlock_irqrestore(&tgpio->lock, flags);
 }
@@ -128,7 +128,7 @@ static void timbgpio_irq_enable(struct irq_data *d)
        unsigned long flags;
 
        spin_lock_irqsave(&tgpio->lock, flags);
-       tgpio->last_ier |= 1 << offset;
+       tgpio->last_ier |= 1UL << offset;
        iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
        spin_unlock_irqrestore(&tgpio->lock, flags);
 }