[PATCH 4.9 43/97] gpio: mpc8xxx: Add platform device to gpiochip->parent

Greg Kroah-Hartman
2020-01-22T09:35:12Z

From: Johnson CH Chen (陳昭勳) <JohnsonCH.Chen@moxa.com>

[ Upstream commit 322f6a3182d42df18059a89c53b09d33919f755e ]

Dear Linus Walleij,

In old kernels, some APIs still try to use parent->of_node from struct gpio_chip,
and it could be resulted in kernel panic because parent is NULL. Adding platform
device to gpiochip->parent can fix this problem.

Signed-off-by: Johnson Chen <johnsonch.chen@moxa.com>
Link: https://patchwork.kernel.org/patch/11234609
Link: https://lore.kernel.org/r/HK0PR01MB3521489269F76467DFD7843FFA450@HK0PR01MB3521.apcprd01.prod.exchangelabs.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpio/gpio-mpc8xxx.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/gpio/gpio-mpc8xxx.c b/drivers/gpio/gpio-mpc8xxx.c
index bd777687233b..b67f61d31e25 100644
--- a/drivers/gpio/gpio-mpc8xxx.c
+++ b/drivers/gpio/gpio-mpc8xxx.c
@@ -306,6 +306,7 @@ static int mpc8xxx_probe(struct platform_device *pdev)
return -ENOMEM;

gc = &mpc8xxx_gc->gc;
+ gc->parent = &pdev->dev;

if (of_property_read_bool(np, "little-endian")) {
ret = bgpio_init(gc, &pdev->dev, 4,
--
2.20.1