[PATCH] PCI: mvebu: Check if reset gpio is defined

["Pali Rohár" <pali@kernel.org>]

Reset gpio is optional and it does not have to be defined for all boards.

So in mvebu_pcie_powerdown() like in mvebu_pcie_powerup() check that reset
gpio is defined prior usage to prevent NULL pointer dereference.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 drivers/pci/controller/pci-mvebu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
index 153a64676bc9..58607cbe84c8 100644
--- a/drivers/pci/controller/pci-mvebu.c
+++ b/drivers/pci/controller/pci-mvebu.c
@@ -947,7 +947,8 @@ static int mvebu_pcie_powerup(struct mvebu_pcie_port *port)
  */
 static void mvebu_pcie_powerdown(struct mvebu_pcie_port *port)
 {
-	gpiod_set_value_cansleep(port->reset_gpio, 1);
+	if (port->reset_gpio)
+		gpiod_set_value_cansleep(port->reset_gpio, 1);
 
 	clk_disable_unprepare(port->clk);
 }
-- 
2.20.1