PCI: Wait for device to become ready after secondary bus reset

Setting Secondary Bus Reset of a downstream port sends a hot reset.  PCIe
r4.0, sec 2.3.1, Request Handling Rules, indicates that a device can return
CRS Completion Status following such a reset.  Wait until the device
becomes ready in that situation.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index dde4050..0b8e8ee 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4233,7 +4233,7 @@ int pci_reset_bridge_secondary_bus(struct pci_dev *dev)
 {
 	pcibios_reset_secondary_bus(dev);
 
-	return 0;
+	return pci_dev_wait(dev, "bus reset", PCIE_RESET_READY_POLL_MS);
 }
 EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus);