of: base: Improve argument length mismatch error

commit 5d05b811b5acb92fc581a7b328b36646c86f5ab9 upstream.

The cells_name field of of_phandle_iterator might be NULL. Use the
phandle name instead. With this change instead of:

  OF: /soc/pinctrl@1000000: (null) = 3 found 2

We get:

  OF: /soc/pinctrl@1000000: phandle pinctrl@1000000 needs 3, found 2

Which is a more helpful messages making DT debugging easier.

In this particular example the phandle name looks like duplicate of the
same node name. But note that the first node is the parent node
(it->parent), while the second is the phandle target (it->node). They
happen to be the same in the case that triggered this improvement. See
commit 72cb4c48a46a ("arm64: dts: qcom: ipq6018: Fix gpio-ranges
property").

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/f6a68e0088a552ea9dfd4d8e3b5b586d92594738.1640881913.git.baruch@tkos.co.il
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/of/base.c b/drivers/of/base.c
index a240211653789b5fbabb0ea42c69d38d2dd6631e..b5c84607a74bf453736c9f8f3244b018b59a2235 100644 (file)
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1366,9 +1366,14 @@ int of_phandle_iterator_next(struct of_phandle_iterator *it)
                 * property data length
                 */
                if (it->cur + count > it->list_end) {
-                       pr_err("%pOF: %s = %d found %td\n",
-                              it->parent, it->cells_name,
-                              count, it->list_end - it->cur);
+                       if (it->cells_name)
+                               pr_err("%pOF: %s = %d found %td\n",
+                                       it->parent, it->cells_name,
+                                       count, it->list_end - it->cur);
+                       else
+                               pr_err("%pOF: phandle %s needs %d, found %td\n",
+                                       it->parent, of_node_full_name(it->node),
+                                       count, it->list_end - it->cur);
                        goto err;
                }
        }