[PATCH] gpio: msic: Fix calculating register address in msic_gpio_to_oreg()

[Axel Lin <axel.lin@gmail.com>]

In the case offset is 20 ... 23, the equation to get the register should be:
        INTEL_MSIC_GPIO1HV0CTLO - offset + 20

With above equation, we can get below mapping between offset and the register:
        offset is 20: INTEL_MSIC_GPIO1HV0CTLO
        offset is 21: INTEL_MSIC_GPIO1HV1CTLO
        offset is 22: INTEL_MSIC_GPIO1HV2CTLO
        offset is 23: INTEL_MSIC_GPIO1HV3CTLO

Signed-off-by: Axel Lin <axel.lin@gmail.com>
---
 drivers/gpio/gpio-msic.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-msic.c b/drivers/gpio/gpio-msic.c
index 71a838f..b389862 100644
--- a/drivers/gpio/gpio-msic.c
+++ b/drivers/gpio/gpio-msic.c
@@ -99,7 +99,7 @@ static int msic_gpio_to_oreg(unsigned offset)
 	if (offset < 20)
 		return INTEL_MSIC_GPIO0HV0CTLO - offset + 16;
 
-	return INTEL_MSIC_GPIO1HV0CTLO + offset + 20;
+	return INTEL_MSIC_GPIO1HV0CTLO - offset + 20;
 }
 
 static int msic_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
-- 
1.7.9.5