leds: pca9532: correct shift computation in pca9532_getled

Each led setting occupies two bits in a corresponding led register.
Accessing these bits requires shifting and masking, which was
implemented incorrectly in pca9532_getled. Two new helper macros
concentrate the computation of those masks in one place.

Signed-off-by: Markus Moll <mmoll@de.pepperl-fuchs.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

diff --git a/drivers/leds/leds-pca9532.c b/drivers/leds/leds-pca9532.c
index 41229f7..d37fd95 100644 (file)
--- a/drivers/leds/leds-pca9532.c
+++ b/drivers/leds/leds-pca9532.c
@@ -27,6 +27,8 @@
 #define PCA9532_REG_PWM(m, i)  (PCA9532_REG_OFFSET(m) + 0x2 + (i) * 2)
 #define LED_REG(m, led)                (PCA9532_REG_OFFSET(m) + 0x5 + (led >> 2))
 #define LED_NUM(led)           (led & 0x3)
+#define LED_SHIFT(led)         (LED_NUM(led) * 2)
+#define LED_MASK(led)          (0x3 << LED_SHIFT(led))
 
 #define ldev_to_led(c)       container_of(c, struct pca9532_led, ldev)
 
@@ -162,9 +164,9 @@ static void pca9532_setled(struct pca9532_led *led)
        mutex_lock(&data->update_lock);
        reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
        /* zero led bits */
-       reg = reg & ~(0x3<<LED_NUM(led->id)*2);
+       reg = reg & ~LED_MASK(led->id);
        /* set the new value */
-       reg = reg | (led->state << LED_NUM(led->id)*2);
+       reg = reg | (led->state << LED_SHIFT(led->id));
        i2c_smbus_write_byte_data(client, LED_REG(maxleds, led->id), reg);
        mutex_unlock(&data->update_lock);
 }
@@ -260,7 +262,7 @@ static enum pca9532_state pca9532_getled(struct pca9532_led *led)
 
        mutex_lock(&data->update_lock);
        reg = i2c_smbus_read_byte_data(client, LED_REG(maxleds, led->id));
-       ret = reg >> LED_NUM(led->id)/2;
+       ret = (reg & LED_MASK(led->id)) >> LED_SHIFT(led->id);
        mutex_unlock(&data->update_lock);
        return ret;
 }