gpio: ich: Use BIT() macro

Using BIT() makes (1 << foo) constructions easier to read, and
also account for common mistakes where bit 31 is not working
because of numbers being interpreted as negative unless
specified as unsigned.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-ich.c b/drivers/gpio/gpio-ich.c
index 7a54165..dba3922 100644 (file)
--- a/drivers/gpio/gpio-ich.c
+++ b/drivers/gpio/gpio-ich.c
@@ -26,6 +26,7 @@
 #include <linux/gpio/driver.h>
 #include <linux/platform_device.h>
 #include <linux/mfd/lpc_ich.h>
+#include <linux/bitops.h>
 
 #define DRV_NAME "gpio_ich"
 
@@ -131,9 +132,9 @@ static int ichx_write_bit(int reg, unsigned nr, int val, int verify)
                                 ichx_priv.gpio_base);
 
        if (val)
-               data |= 1 << bit;
+               data |= BIT(bit);
        else
-               data &= ~(1 << bit);
+               data &= ~BIT(bit);
        ICHX_WRITE(data, ichx_priv.desc->regs[reg][reg_nr],
                         ichx_priv.gpio_base);
        if (reg == GPIO_LVL && ichx_priv.desc->use_outlvl_cache)
@@ -166,12 +167,12 @@ static int ichx_read_bit(int reg, unsigned nr)
 
        spin_unlock_irqrestore(&ichx_priv.lock, flags);
 
-       return data & (1 << bit) ? 1 : 0;
+       return !!(data & BIT(bit));
 }
 
 static bool ichx_gpio_check_available(struct gpio_chip *gpio, unsigned nr)
 {
-       return !!(ichx_priv.use_gpio & (1 << (nr / 32)));
+       return !!(ichx_priv.use_gpio & BIT(nr / 32));
 }
 
 static int ichx_gpio_get_direction(struct gpio_chip *gpio, unsigned nr)
@@ -232,12 +233,12 @@ static int ich6_gpio_get(struct gpio_chip *chip, unsigned nr)
                spin_lock_irqsave(&ichx_priv.lock, flags);
 
                /* GPI 0 - 15 are latched, write 1 to clear*/
-               ICHX_WRITE(1 << (16 + nr), 0, ichx_priv.pm_base);
+               ICHX_WRITE(BIT(16 + nr), 0, ichx_priv.pm_base);
                data = ICHX_READ(0, ichx_priv.pm_base);
 
                spin_unlock_irqrestore(&ichx_priv.lock, flags);
 
-               return (data >> 16) & (1 << nr) ? 1 : 0;
+               return !!((data >> 16) & BIT(nr));
        } else {
                return ichx_gpio_get(chip, nr);
        }
@@ -254,7 +255,7 @@ static int ichx_gpio_request(struct gpio_chip *chip, unsigned nr)
         * the chipset's USE value can be trusted for this specific bit.
         * If it can't be trusted, assume that the pin can be used as a GPIO.
         */
-       if (ichx_priv.desc->use_sel_ignore[nr / 32] & (1 << (nr & 0x1f)))
+       if (ichx_priv.desc->use_sel_ignore[nr / 32] & BIT(nr & 0x1f))
                return 0;
 
        return ichx_read_bit(GPIO_USE_SEL, nr) ? 0 : -ENODEV;
@@ -394,7 +395,7 @@ static int ichx_gpio_request_regions(struct device *dev,
                return -ENODEV;
 
        for (i = 0; i < ARRAY_SIZE(ichx_priv.desc->regs[0]); i++) {
-               if (!(use_gpio & (1 << i)))
+               if (!(use_gpio & BIT(i)))
                        continue;
                if (!devm_request_region(dev,
                                res_base->start + ichx_priv.desc->regs[0][i],