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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/arch/powerpc/platforms/pseries/of_helpers.c
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/powerpc/platforms/pseries/of_helpers.c')
-rw-r--r--kernel/arch/powerpc/platforms/pseries/of_helpers.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/platforms/pseries/of_helpers.c b/kernel/arch/powerpc/platforms/pseries/of_helpers.c
new file mode 100644
index 000000000..2798933c0
--- /dev/null
+++ b/kernel/arch/powerpc/platforms/pseries/of_helpers.c
@@ -0,0 +1,38 @@
+#include <linux/string.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+
+#include "of_helpers.h"
+
+/**
+ * pseries_of_derive_parent - basically like dirname(1)
+ * @path: the full_name of a node to be added to the tree
+ *
+ * Returns the node which should be the parent of the node
+ * described by path. E.g., for path = "/foo/bar", returns
+ * the node with full_name = "/foo".
+ */
+struct device_node *pseries_of_derive_parent(const char *path)
+{
+ struct device_node *parent;
+ char *parent_path = "/";
+ const char *tail;
+
+ /* We do not want the trailing '/' character */
+ tail = kbasename(path) - 1;
+
+ /* reject if path is "/" */
+ if (!strcmp(path, "/"))
+ return ERR_PTR(-EINVAL);
+
+ if (tail > path) {
+ parent_path = kstrndup(path, tail - path, GFP_KERNEL);
+ if (!parent_path)
+ return ERR_PTR(-ENOMEM);
+ }
+ parent = of_find_node_by_path(parent_path);
+ if (strcmp(parent_path, "/"))
+ kfree(parent_path);
+ return parent ? parent : ERR_PTR(-EINVAL);
+}