Some platforms are not setting of_node in the driver. On these platforms
defining gpio-reserved-ranges on device tree leads to kernel crash.
It is due to some parts of the gpio core relying on the driver to set up
of_node,while other parts do themselves.This inconsistent behaviour leads
to a crash.
gpiochip_add_data_with_key() calls gpiochip_init_valid_mask() with of_node
as NULL. of_gpiochip_add() fills "of_node" and calls
of_gpiochip_init_valid_mask().
The fix is to move the assignment to chip->of_node from of_gpiochip_add()
to gpiochip_add_data_with_key().
Signed-off-by: Biju Das <biju.das@xxxxxxxxxxxxxx>
---
drivers/gpio/gpiolib-of.c | 3 ---
drivers/gpio/gpiolib.c | 2 ++
2 files changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 28d9680..91174bf 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -620,9 +620,6 @@ int of_gpiochip_add(struct gpio_chip *chip)
{
int status;
- if ((!chip->of_node) && (chip->parent))
- chip->of_node = chip->parent->of_node;
-
if (!chip->of_node)
return 0;
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index e11a3bb..20fe531 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1256,6 +1256,8 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
/* If the gpiochip has an assigned OF node this takes precedence */
if (chip->of_node)
gdev->dev.of_node = chip->of_node;
+ else
+ chip->of_node = gdev->dev.of_node;
#endif
gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
--
2.7.4
