[PATCH v3 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 | 12 ++++++------
 drivers/pci/controller/dwc/pcie-designware.h      |  1 +
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 68a9dac23b1b..7e9dad7ba056 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -341,7 +341,7 @@ int dw_pcie_host_init(struct pcie_port *pp)
 	struct device_node *np = dev->of_node;
 	struct platform_device *pdev = to_platform_device(dev);
 	struct resource_entry *win, *tmp;
-	struct pci_bus *bus, *child;
+	struct pci_bus *child;
 	struct pci_host_bridge *bridge;
 	struct resource *cfg_res;
 	int ret;
@@ -496,18 +496,18 @@ int dw_pcie_host_init(struct pcie_port *pp)
 	if (ret)
 		goto err_free_msi;
 
-	bus = bridge->bus;
+	pp->root_bus = bridge->bus;
 
 	if (pp->ops->scan_bus)
 		pp->ops->scan_bus(pp);
 
-	pci_bus_size_bridges(bus);
-	pci_bus_assign_resources(bus);
+	pci_bus_size_bridges(pp->root_bus);
+	pci_bus_assign_resources(pp->root_bus);
 
-	list_for_each_entry(child, &bus->children, node)
+	list_for_each_entry(child, &pp->root_bus->children, node)
 		pcie_bus_configure_settings(child);
 
-	pci_bus_add_devices(bus);
+	pci_bus_add_devices(pp->root_bus);
 	return 0;
 
 err_free_msi:
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 6fb0a1879932..adff0c713665 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