UPSTREAM: of/pci: Add helper function to parse max-link-speed from dt

[firefly-linux-kernel-4.4.55.git] / drivers / of / of_pci.c

diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index ff27177f49edbdd3105b319c7deee29ed48da869..038c0ec1b0c523b6d2a191f1476d9684efc270c7 100644 (file)
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -118,6 +118,27 @@ 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
@@ -143,26 +164,6 @@ void of_pci_check_probe_only(void)
 }
 EXPORT_SYMBOL_GPL(of_pci_check_probe_only);
 
-/**
- * of_pci_dma_configure - Setup DMA configuration
- * @dev: ptr to pci_dev struct of the PCI device
- *
- * Function to update PCI devices's DMA configuration using the same
- * info from the OF node of host bridge's parent (if any).
- */
-void of_pci_dma_configure(struct pci_dev *pci_dev)
-{
-       struct device *dev = &pci_dev->dev;
-       struct device *bridge = pci_get_host_bridge_device(pci_dev);
-
-       if (!bridge->parent)
-               return;
-
-       of_dma_configure(dev, bridge->parent->of_node);
-       pci_put_host_bridge_device(bridge);
-}
-EXPORT_SYMBOL_GPL(of_pci_dma_configure);
-
 #if defined(CONFIG_OF_ADDRESS)
 /**
  * of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT