[PATCH 2/2] dma: of: allow for non-existent #dma-cells property

[Rob Herring <robherring2@gmail.com>]

From: Rob Herring <rob.herring@calxeda.com>

Allow the #dma-cells property to be optional and default to 0. This fixes
a crash on Calxed highbank which has no clients and no #dma-cells property.

Also, the error check was pointless as be32_to_cpup causes a NULL ptr error
first before we get to the error check.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <djbw@fb.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
---
 drivers/dma/of-dma.c |   10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index 69d04d2..e97a062 100644
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -92,7 +92,7 @@ int of_dma_controller_register(struct device_node *np,
 				void *data)
 {
 	struct of_dma	*ofdma;
-	int		nbcells;
+	int		nbcells = 0;
 
 	if (!np || !of_dma_xlate) {
 		pr_err("%s: not enough information provided\n", __func__);
@@ -103,13 +103,7 @@ int of_dma_controller_register(struct device_node *np,
 	if (!ofdma)
 		return -ENOMEM;
 
-	nbcells = be32_to_cpup(of_get_property(np, "#dma-cells", NULL));
-	if (!nbcells) {
-		pr_err("%s: #dma-cells property is missing or invalid\n",
-		       __func__);
-		kfree(ofdma);
-		return -EINVAL;
-	}
+        of_property_read_u32(np, "#dma-cells", &nbcells);
 
 	ofdma->of_node = np;
 	ofdma->of_dma_nbcells = nbcells;
-- 
1.7.10.4