[PATCH v2] lib: utils/gpio: respect flag GPIO_FLAG_ACTIVE_LOW

[Inochi Amaoto]

"gpio-poweroff" and "gpio-restart" always set gpio to high to
active the function, but some chips need a low signal to active.
Fortunately, it can be achieved by setting GPIO_FLAG_ACTIVE_LOW
for the gpio. Implement this flag support for the gpio library
so the gpio reset can function well.

Signed-off-by: Inochi Amaoto <inochiama at outlook.com>
---
Changed from v1:
1. drop unnecessary braces.
2. fix typo in title.
---
 lib/utils/gpio/gpio.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/lib/utils/gpio/gpio.c b/lib/utils/gpio/gpio.c
index 3a3a6b2..6ffe929 100644
--- a/lib/utils/gpio/gpio.c
+++ b/lib/utils/gpio/gpio.c
@@ -73,17 +73,26 @@ int gpio_direction_output(struct gpio_pin *gp, int value)
 	if (!gp->chip->direction_output)
 		return SBI_ENOSYS;

+	if (gp->flags & GPIO_FLAG_ACTIVE_LOW)
+		value = value == 0 ? 1 : 0;
+
 	return gp->chip->direction_output(gp, value);
 }

 int gpio_get(struct gpio_pin *gp)
 {
+	int value;
+
 	if (!gp || !gp->chip || (gp->chip->ngpio <= gp->offset))
 		return SBI_EINVAL;
 	if (!gp->chip->get)
 		return SBI_ENOSYS;

-	return gp->chip->get(gp);
+	value = gp->chip->get(gp);
+
+	if (gp->flags & GPIO_FLAG_ACTIVE_LOW)
+		value = value == 0 ? 1 : 0;
+	return value;
 }

 int gpio_set(struct gpio_pin *gp, int value)
@@ -93,6 +102,9 @@ int gpio_set(struct gpio_pin *gp, int value)
 	if (!gp->chip->set)
 		return SBI_ENOSYS;

+	if (gp->flags & GPIO_FLAG_ACTIVE_LOW)
+		value = value == 0 ? 1 : 0;
+
 	gp->chip->set(gp, value);
 	return 0;
 }
--
2.45.1