MIPS: RB532: Auto disable GPIO alternate function

When a driver calls gpio_set_direction_{input,output}(), it obviously
doesn't want the alternate function for that pin to be active (as the
direction would not matter in that case). This patch ensures alternate
function is disabled when the direction is being changed.
Signed-off-by: NPhil Sutter <n0-1@freewrt.org>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

arch/mips/rb532/gpio.c

@@ -169,8 +169,8 @@ static int rb532_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 
 	gpch = container_of(chip, struct rb532_gpio_chip, chip);
 
-	if (rb532_get_bit(offset, gpch->regbase + GPIOFUNC))
-		return 1;	/* alternate function, GPIOCFG is ignored */
+	/* disable alternate function in case it's set */
+	rb532_set_bit(0, offset, gpch->regbase + GPIOFUNC);
 
 	rb532_set_bit(0, offset, gpch->regbase + GPIOCFG);
 	return 0;
@@ -186,8 +186,8 @@ static int rb532_gpio_direction_output(struct gpio_chip *chip,
 
 	gpch = container_of(chip, struct rb532_gpio_chip, chip);
 
-	if (rb532_get_bit(offset, gpch->regbase + GPIOFUNC))
-		return 1;	/* alternate function, GPIOCFG is ignored */
+	/* disable alternate function in case it's set */
+	rb532_set_bit(0, offset, gpch->regbase + GPIOFUNC);
 
 	/* set the initial output value */
 	rb532_set_bit(value, offset, gpch->regbase + GPIOD);