[PATCH v2] gpio: mmio: fix calculation of bgpio_bits

[Asmaa Mnebhi <asmaa@nvidia.com>]

If the "ngpios" property is specified, bgpio_bits is calculated
as the round up value of ngpio. At the moment, the only requirement
specified is that the round up value must be a multiple of 8 but
it should also be a power of 2 because we provide accessors based
on the bank size in bgpio_setup_accessors().

Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/gpio/gpio-mmio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c
index b52a3dd511ca..74fdf0d87b2c 100644
--- a/drivers/gpio/gpio-mmio.c
+++ b/drivers/gpio/gpio-mmio.c
@@ -623,7 +623,7 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev,
 	if (ret)
 		gc->ngpio = gc->bgpio_bits;
 	else
-		gc->bgpio_bits = round_up(gc->ngpio, 8);
+		gc->bgpio_bits = roundup_pow_of_two(round_up(gc->ngpio, 8));
 
 	ret = bgpio_setup_io(gc, dat, set, clr, flags);
 	if (ret)
-- 
2.30.1