+/**
+ * dm_pci_find_next_ext_capability() - find an extended capability
+ * starting from an offset
+ *
+ * Tell if a device supports a given PCI express extended capability.
+ * Returns the address of the requested extended capability structure
+ * within the device's PCI configuration space or 0 in case the device
+ * does not support it.
+ *
+ * Possible values for @cap:
+ *
+ * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
+ * %PCI_EXT_CAP_ID_VC Virtual Channel
+ * %PCI_EXT_CAP_ID_DSN Device Serial Number
+ * %PCI_EXT_CAP_ID_PWR Power Budgeting
+ *
+ * See PCI_EXT_CAP_ID_xxx for the complete extended capability ID codes.
+ *
+ * @dev: PCI device to query
+ * @start: offset to start from
+ * @cap: extended capability code
+ * @return: extended capability address or 0 if not supported
+ */
+int dm_pci_find_next_ext_capability(struct udevice *dev, int start, int cap);
+