'dma-ranges' frequently exists without parent nodes having 'dma-ranges'.
While this is an error for 'ranges', this is fine because DMA capable
devices always have a translatable DMA address. Also, with no
'dma-ranges' at all, the assumption is that DMA addresses are 1:1 with
no restrictions unless perhaps the device itself has implicit
restrictions.

Cc: Robin Murphy <robin.mur...@arm.com>
Signed-off-by: Rob Herring <r...@kernel.org>
---
 drivers/of/address.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/of/address.c b/drivers/of/address.c
index e918001c7798..5b835d332709 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -519,9 +519,13 @@ static int of_translate_one(struct device_node *parent, 
struct of_bus *bus,
         *
         * As far as we know, this damage only exists on Apple machines, so
         * This code is only enabled on powerpc. --gcl
+        *
+        * This quirk also applies for 'dma-ranges' which frequently exist in
+        * child nodes without 'dma-ranges' in the parent nodes. --RobH
         */
        ranges = of_get_property(parent, rprop, &rlen);
-       if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
+       if (ranges == NULL && !of_empty_ranges_quirk(parent) &&
+           strcmp(rprop, "dma-ranges")) {
                pr_debug("no ranges; cannot translate\n");
                return 1;
        }
-- 
2.20.1

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