diff --git a/target/linux/ramips/files/arch/mips/pci/pci-rt288x.c b/target/linux/ramips/files/arch/mips/pci/pci-rt288x.c
index 4360e63657..1c9df5df53 100644
--- a/target/linux/ramips/files/arch/mips/pci/pci-rt288x.c
+++ b/target/linux/ramips/files/arch/mips/pci/pci-rt288x.c
@@ -192,7 +192,7 @@ int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
 	int irq = -1;
 
 	if (dev->bus->number != 0)
-		return 0;
+		return irq;
 
 	switch (PCI_SLOT(dev->devfn)) {
 	case 0x00: