On boot, gpiochip_add_data() initializes the FLAG_IS_OUT bit in
desc->flags iff its gpio_chip does not have ->direction_input() handler,
else it is initialized to 0, which implies the GPIO is an "input".
Later, the sysfs "direction" handler will use gpiod_get_direction() to
get the current direction, but if no ->get_direction() handler is
installed, the result will just be the current (initial) value of flags,
which will always be OUT irregardless of the initial register value.
Add a get_direction() handler to pinctrl-amd to fix this and always
provide the correct value for direction.
Signed-off-by: Daniel Kurtz <djku...@chromium.org>
---
drivers/pinctrl/pinctrl-amd.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c
index 61d830c2bc17..281b700fe7e9 100644
--- a/drivers/pinctrl/pinctrl-amd.c
+++ b/drivers/pinctrl/pinctrl-amd.c
@@ -40,6 +40,19 @@
#include "pinctrl-utils.h"
#include "pinctrl-amd.h"
+static int amd_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
+{
+ unsigned long flags;
+ u32 pin_reg;
+ struct amd_gpio *gpio_dev = gpiochip_get_data(gc);
+
+ raw_spin_lock_irqsave(&gpio_dev->lock, flags);
+ pin_reg = readl(gpio_dev->base + offset * 4);
+ raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
+
+ return !(pin_reg & BIT(OUTPUT_ENABLE_OFF));
+}
+
static int amd_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
{
unsigned long flags;
@@ -845,6 +858,7 @@ static int amd_gpio_probe(struct platform_device *pdev)
#endif
gpio_dev->pdev = pdev;
+ gpio_dev->gc.get_direction = amd_gpio_get_direction;
gpio_dev->gc.direction_input = amd_gpio_direction_input;
gpio_dev->gc.direction_output = amd_gpio_direction_output;
gpio_dev->gc.get = amd_gpio_get_value;
--
2.16.1.291.g4437f3f132-goog
