of: address: Don't fail a lookup just because a node has no reg property

Sometimes it doesn't make any sense for a node to have an address.
In this case device lookup will always be unsuccessful because we
currently assume every node will have a reg property. This patch
changes the semantics so that the resource address and the lookup
address will only be compared if one exists.

Things like AUXDATA() rely on of_dev_lookup to return the lookup
entry of a particular device in order to do things like apply
platform_data to a device. However, this is currently broken for
nodes which do not have a reg property, meaning that platform_data
can not be passed in those cases.

Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 343ad29e211c66768491e325046ff0b58bcb15ec..96004807dd280e1a12e8427f36becc0090804da9 100644 (file)
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -317,10 +317,9 @@ static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *l
        for(; lookup->compatible != NULL; lookup++) {
                if (!of_device_is_compatible(np, lookup->compatible))
                        continue;
-               if (of_address_to_resource(np, 0, &res))
-                       continue;
-               if (res.start != lookup->phys_addr)
-                       continue;
+               if (!of_address_to_resource(np, 0, &res))
+                       if (res.start != lookup->phys_addr)
+                               continue;
                pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
                return lookup;
        }