[RFC 15/15] PCI: make pcibios_add_bus/remove_bus callbacks

[Arnd Bergmann <arnd@xxxxxxxx>]

These are mostly not architecture specific but are meant for particular
PCI host bridge implementations, in particular for the ACPI version.

Turn them both into callback functions that are implemented by the
APCI PCI implementation as well as the one architecture that overrides
pcibios_remove_bus.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
 arch/arm64/kernel/pci.c | 10 ----------
 arch/ia64/pci/pci.c     | 10 ----------
 arch/s390/pci/pci.c     |  3 ++-
 arch/x86/pci/common.c   | 10 ----------
 drivers/acpi/pci_root.c |  2 ++
 drivers/pci/probe.c     | 12 ++++++++++--
 include/linux/pci.h     |  2 ++
 7 files changed, 16 insertions(+), 33 deletions(-)

diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
index 8958a7c32a9f..99fac25efe88 100644
--- a/arch/arm64/kernel/pci.c
+++ b/arch/arm64/kernel/pci.c
@@ -191,14 +191,4 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
 	return bus;
 }
 
-void pcibios_add_bus(struct pci_bus *bus)
-{
-	acpi_pci_add_bus(bus);
-}
-
-void pcibios_remove_bus(struct pci_bus *bus)
-{
-	acpi_pci_remove_bus(bus);
-}
-
 #endif
diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
index 511b8a058d80..f47e0920d308 100644
--- a/arch/ia64/pci/pci.c
+++ b/arch/ia64/pci/pci.c
@@ -367,16 +367,6 @@ void pcibios_fixup_bus(struct pci_bus *b)
 	platform_pci_fixup_bus(b);
 }
 
-void pcibios_add_bus(struct pci_bus *bus)
-{
-	acpi_pci_add_bus(bus);
-}
-
-void pcibios_remove_bus(struct pci_bus *bus)
-{
-	acpi_pci_remove_bus(bus);
-}
-
 void pcibios_set_master (struct pci_dev *dev)
 {
 	/* No special bus mastering setup handling */
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index b21205f131ce..120beb83b6a5 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -769,7 +769,7 @@ static void zpci_free_domain(struct zpci_dev *zdev)
 	spin_unlock(&zpci_domain_lock);
 }
 
-void pcibios_remove_bus(struct pci_bus *bus)
+static void zpci_remove_bus(struct pci_bus *bus)
 {
 	struct zpci_dev *zdev = get_zdev_by_bus(bus);
 
@@ -801,6 +801,7 @@ static struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
 	bridge->sysdata = sysdata;
 	bridge->busnr = bus;
 	bridge->ops = ops;
+	bridge->remove_bus = zpci_remove_bus;
 
 	error = pci_scan_root_bus_bridge(bridge);
 	if (error < 0)
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 920d0885434c..987e6fefd5d3 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -168,16 +168,6 @@ void pcibios_fixup_bus(struct pci_bus *b)
 		pcibios_fixup_device_resources(dev);
 }
 
-void pcibios_add_bus(struct pci_bus *bus)
-{
-	acpi_pci_add_bus(bus);
-}
-
-void pcibios_remove_bus(struct pci_bus *bus)
-{
-	acpi_pci_remove_bus(bus);
-}
-
 /*
  * Only use DMI information to set this if nothing was passed
  * on the kernel command line (which was parsed earlier).
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 5da0f70c4e65..cf7a9a7bf1e7 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -911,6 +911,8 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
 	bridge->busnr = busnum;
 	bridge->ops = ops->pci_ops;
 	bridge->prepare = acpi_pci_root_bridge_prepare;
+	bridge->add_bus = acpi_pci_add_bus;
+	bridge->remove_bus = acpi_pci_remove_bus;
 	pci_set_host_bridge_release(bridge, acpi_pci_root_release_info,
 				    info);
 
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index f493d7e299e6..86a678fa8c13 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -2905,12 +2905,20 @@ unsigned int pci_scan_child_bus(struct pci_bus *bus)
 }
 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
 
-void __weak pcibios_add_bus(struct pci_bus *bus)
+void pcibios_add_bus(struct pci_bus *bus)
 {
+	struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
+
+	if (bridge->add_bus)
+		bridge->add_bus(bus);
 }
 
-void __weak pcibios_remove_bus(struct pci_bus *bus)
+void pcibios_remove_bus(struct pci_bus *bus)
 {
+	struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
+
+	if (bridge->remove_bus)
+		bridge->remove_bus(bus);
 }
 
 int pci_host_probe(struct pci_host_bridge *bridge)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 24216daef6f8..bc9635313747 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -479,6 +479,8 @@ struct pci_host_bridge {
 	void (*bus_add_device)(struct pci_dev *pdev);
 	int (*alloc_irq)(struct pci_dev *);
 	int (*free_irq)(struct pci_dev *);
+	void (*add_bus)(struct pci_bus *);
+	void (*remove_bus)(struct pci_bus *);
 	void		*release_data;
 	struct msi_controller *msi;
 	unsigned int	ignore_reset_delay:1;	/* For entire hierarchy */
-- 
2.18.0