svn commit: r284624 - head/sys/dev/ofw

[Warner Losh]

Author: imp
Date: Sat Jun 20 04:48:48 2015
New Revision: 284624
URL: https://svnweb.freebsd.org/changeset/base/284624

Log:
  Add ofw_bus_find_child_by_phandle, a helper routine to find a device_t
  child matchig a given phandle_t.
  
  Differential Revision: https://reviews.freebsd.org/D2871

Modified:
  head/sys/dev/ofw/ofw_bus_subr.c
  head/sys/dev/ofw/ofw_bus_subr.h

Modified: head/sys/dev/ofw/ofw_bus_subr.c
==============================================================================
--- head/sys/dev/ofw/ofw_bus_subr.c	Sat Jun 20 04:02:33 2015	(r284623)
+++ head/sys/dev/ofw/ofw_bus_subr.c	Sat Jun 20 04:48:48 2015	(r284624)
@@ -551,3 +551,44 @@ ofw_bus_find_compatible(phandle_t node, 
 	}
 	return (0);
 }
+
+/**
+ * @brief Return child of bus whose phandle is node
+ *
+ * A direct child of @p will be returned if it its phandle in the
+ * OFW tree is @p node. Otherwise, NULL is returned.
+ *
+ * @param bus		The bus to examine
+ * @param node		The phandle_t to look for.
+ */
+device_t
+ofw_bus_find_child_device_by_phandle(device_t bus, phandle_t node)
+{
+	device_t *children, retval, child;
+	int nkid, i;
+
+	/*
+	 * Nothing can match the flag value for no node.
+	 */
+	if (node == -1)
+		return (NULL);
+
+	/*
+	 * Search the children for a match. We microoptimize
+	 * a bit by not using ofw_bus_get since we already know
+	 * the parent. We do not recurse.
+	 */
+	if (device_get_children(bus, &children, &nkid) != 0)
+		return (NULL);
+	retval = NULL;
+	for (i = 0; i < nkid; i++) {
+		child = children[i];
+		if (OFW_BUS_GET_NODE(bus, child) == node) {
+			retval = child;
+			break;
+		}
+	}
+	free(children, M_TEMP);
+
+	return (retval);
+}

Modified: head/sys/dev/ofw/ofw_bus_subr.h
==============================================================================
--- head/sys/dev/ofw/ofw_bus_subr.h	Sat Jun 20 04:02:33 2015	(r284623)
+++ head/sys/dev/ofw/ofw_bus_subr.h	Sat Jun 20 04:48:48 2015	(r284624)
@@ -107,4 +107,7 @@ phandle_t ofw_bus_find_compatible(phandl
 /* Helper to search for a child with a given name */
 phandle_t ofw_bus_find_child(phandle_t, const char *);
 
+/* Helper routine to find a device_t child matchig a given phandle_t */
+device_t ofw_bus_find_child_device_by_phandle(device_t bus, phandle_t node);
+
 #endif /* !_DEV_OFW_OFW_BUS_SUBR_H_ */