diff options
| -rw-r--r-- | drivers/of/of_pci.c | 21 | ||||
| -rw-r--r-- | include/linux/of_pci.h | 7 |
2 files changed, 28 insertions, 0 deletions
diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c index b58be12ab277..0ee42c3e66a1 100644 --- a/drivers/of/of_pci.c +++ b/drivers/of/of_pci.c @@ -120,6 +120,27 @@ int of_get_pci_domain_nr(struct device_node *node) EXPORT_SYMBOL_GPL(of_get_pci_domain_nr); /** + * This function will try to find the limitation of link speed by finding + * a property called "max-link-speed" of the given device node. + * + * @node: device tree node with the max link speed information + * + * Returns the associated max link speed from DT, or a negative value if the + * required property is not found or is invalid. + */ +int of_pci_get_max_link_speed(struct device_node *node) +{ + u32 max_link_speed; + + if (of_property_read_u32(node, "max-link-speed", &max_link_speed) || + max_link_speed > 4) + return -EINVAL; + + return max_link_speed; +} +EXPORT_SYMBOL_GPL(of_pci_get_max_link_speed); + +/** * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only * is present and valid */ diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h index 7fd5cfce9140..0e0974eceb80 100644 --- a/include/linux/of_pci.h +++ b/include/linux/of_pci.h @@ -16,6 +16,7 @@ int of_pci_get_devfn(struct device_node *np); int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin); int of_pci_parse_bus_range(struct device_node *node, struct resource *res); int of_get_pci_domain_nr(struct device_node *node); +int of_pci_get_max_link_speed(struct device_node *node); void of_pci_check_probe_only(void); int of_pci_map_rid(struct device_node *np, u32 rid, const char *map_name, const char *map_mask_name, @@ -62,6 +63,12 @@ static inline int of_pci_map_rid(struct device_node *np, u32 rid, return -EINVAL; } +static inline int +of_pci_get_max_link_speed(struct device_node *node) +{ + return -EINVAL; +} + static inline void of_pci_check_probe_only(void) { } #endif |