[PATCH 5/5] PCI: dwc: save root bus for driver remove

[Jisheng Zhang <Jisheng.Zhang@xxxxxxxxxxxxx>]

Currently dwc host doesn't support the remove, but nothing prevent us
from supporting it. Save the root bus for clean up work in driver
remove code path.

After this patch, the dwc host users could implement its remove as:

static int foo_pcie_remove(struct platform_device *pdev)
{
	...
	pci_stop_root_bus(pp->root_bus);
	pci_remove_root_bus(pp->root_bus);
	dw_pcie_free_msi(pp);
	...
}

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@xxxxxxxxxxxxx>
---
 drivers/pci/controller/dwc/pcie-designware-host.c | 1 +
 drivers/pci/controller/dwc/pcie-designware.h      | 1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 4831c12fee93..ca45a4471ca0 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -496,6 +496,7 @@ int dw_pcie_host_init(struct pcie_port *pp)
 		goto err_free_msi;
 
 	bus = bridge->bus;
+	pp->root_bus = bus;
 
 	if (pp->ops->scan_bus)
 		pp->ops->scan_bus(pp);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 3be7ca9f1fc3..cd92ded606c6 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -182,6 +182,7 @@ struct pcie_port {
 	struct page		*msi_page;
 	u32			num_vectors;
 	u32			irq_mask[MAX_MSI_CTRLS];
+	struct pci_bus		*root_bus;
 	raw_spinlock_t		lock;
 	DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS);
 };
-- 
2.20.1