[PATCH 7/8] PCI: mediatek: fix a leaked reference by adding missing of_node_put

[Wen Yang]

The call to of_get_next_child returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.
irq_domain_add_linear also calls of_node_get to increase refcount,
so irq_domain will not be affected when it is released.

Detected by coccinelle with the following warnings:
./drivers/pci/controller/pcie-mediatek.c:577:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 567, but without a corresponding object release within this function.
./drivers/pci/controller/pcie-mediatek.c:583:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 567, but without a corresponding object release within this function.
./drivers/pci/controller/pcie-mediatek.c:586:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 567, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Cc: Ryder Lee <ryder.lee@xxxxxxxxxxxx>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx>
Cc: linux-pci@xxxxxxxxxxxxxxx
Cc: linux-mediatek@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
---
 drivers/pci/controller/pcie-mediatek.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index 55e471c..e91716a 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -572,6 +572,7 @@ static int mtk_pcie_init_irq_domain(struct mtk_pcie_port *port,
 
 	port->irq_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
 						 &intx_domain_ops, port);
+	of_node_put(pcie_intc_node);
 	if (!port->irq_domain) {
 		dev_err(dev, "failed to get INTx IRQ domain\n");
 		return -ENODEV;
-- 
2.9.5