pci/of: Match PCI devices to OF nodes dynamically
powerpc has two different ways of matching PCI devices to their
corresponding OF node (if any) for historical reasons. The ppc64 one
does a scan looking for matching bus/dev/fn, while the ppc32 one does a
scan looking only for matching dev/fn on each level in order to be
agnostic to busses being renumbered (which Linux does on some
platforms).
This removes both and instead moves the matching code to the PCI core
itself. It's the most logical place to do it: when a pci_dev is created,
we know the parent and thus can do a single level scan for the matching
device_node (if any).
The benefit is that all archs now get the matching for free. There's one
hook the arch might want to provide to match a PHB bus to its device
node. A default weak implementation is provided that looks for the
parent device device node, but it's not entirely reliable on powerpc for
various reasons so powerpc provides its own.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Michal Simek <monstr@monstr.eu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
index 85a27b6..f93e217 100644
--- a/include/linux/of_pci.h
+++ b/include/linux/of_pci.h
@@ -6,4 +6,9 @@
struct pci_dev;
struct of_irq;
int of_irq_map_pci(struct pci_dev *pdev, struct of_irq *out_irq);
+
+struct device_node;
+struct device_node *of_pci_find_child_device(struct device_node *parent,
+ unsigned int devfn);
+
#endif
diff --git a/include/linux/pci.h b/include/linux/pci.h
index c446b5c..e5086e9 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1589,5 +1589,23 @@
int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off,
unsigned int len, const char *kw);
+/* PCI <-> OF binding helpers */
+#ifdef CONFIG_OF
+struct device_node;
+extern void pci_set_of_node(struct pci_dev *dev);
+extern void pci_release_of_node(struct pci_dev *dev);
+extern void pci_set_bus_of_node(struct pci_bus *bus);
+extern void pci_release_bus_of_node(struct pci_bus *bus);
+
+/* Arch may override this (weak) */
+extern struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus);
+
+#else /* CONFIG_OF */
+static inline void pci_set_of_node(struct pci_dev *dev) { }
+static inline void pci_release_of_node(struct pci_dev *dev) { }
+static inline void pci_set_bus_of_node(struct pci_bus *bus) { }
+static inline void pci_release_bus_of_node(struct pci_bus *bus) { }
+#endif /* CONFIG_OF */
+
#endif /* __KERNEL__ */
#endif /* LINUX_PCI_H */