[PATCH 7/9] of: add package-to-path support to pdt

Andres Salomon
2010-08-30T04:02:49Z

package-to-path is a PROM function which tells us the real (full) name of the
node. This provides a hook for that in the prom ops struct, and makes use
of it in the pdt code when attempting to determine a node's name. If the
hook is available, try using it (falling back to looking at the "name"
property if it fails).

Signed-off-by: Andres Salomon <dilinger@queued.net>
---
drivers/of/pdt.c | 43 ++++++++++++++++++++++++++++++++++++++++++-
include/linux/of_pdt.h | 3 +++
2 files changed, 45 insertions(+), 1 deletions(-)

diff --git a/drivers/of/pdt.c b/drivers/of/pdt.c
index 31a4fb8..28295d0 100644
--- a/drivers/of/pdt.c
+++ b/drivers/of/pdt.c
@@ -132,6 +132,47 @@ static char * __init of_pdt_get_one_property(phandle node, const char *name)
return buf;
}

+static char * __init of_pdt_try_pkg2path(phandle node)
+{
+ char *res, *buf = NULL;
+ int len;
+
+ if (!of_pdt_prom_ops->pkg2path)
+ return NULL;
+
+ if (of_pdt_prom_ops->pkg2path(node, buf, 0, &len))
+ return NULL;
+ buf = prom_early_alloc(len + 1);
+ if (of_pdt_prom_ops->pkg2path(node, buf, len, &len)) {
+ pr_err("%s: package-to-path failed\n", __func__);
+ return NULL;
+ }
+
+ res = strrchr(buf, '/');
+ if (!res) {
+ pr_err("%s: couldn't find / in %s\n", __func__, buf);
+ return NULL;
+ }
+ return res+1;
+}
+
+/*
+ * When fetching the node's name, first try using package-to-path; if
+ * that fails (either because the arch hasn't supplied a PROM callback,
+ * or some other random failure), fall back to just looking at the node's
+ * 'name' property.
+ */
+static char * __init of_pdt_build_name(phandle node)
+{
+ char *buf;
+
+ buf = of_pdt_try_pkg2path(node);
+ if (!buf)
+ buf = of_pdt_get_one_property(node, "name");
+
+ return buf;
+}
+
static struct device_node * __init of_pdt_create_node(phandle node,
struct device_node *parent)
{
@@ -146,7 +187,7 @@ static struct device_node * __init of_pdt_create_node(phandle node,

kref_init(&dp->kref);

- dp->name = of_pdt_get_one_property(node, "name");
+ dp->name = of_pdt_build_name(node);
dp->type = of_pdt_get_one_property(node, "device_type");
dp->phandle = node;

diff --git a/include/linux/of_pdt.h b/include/linux/of_pdt.h
index a057417..9945e58 100644
--- a/include/linux/of_pdt.h
+++ b/include/linux/of_pdt.h
@@ -29,6 +29,9 @@ struct of_pdt_ops {
/* phandles are 0 if no child or sibling exists */
phandle (*getchild)(phandle parent);
phandle (*getsibling)(phandle node);
+
+ /* return 0 on success; fill in 'len' with number of bytes in path */
+ int (*pkg2path)(phandle node, char *buf, const int buflen, int *len);
};

extern void *prom_early_alloc(unsigned long size);
--
1.5.6.5