[PATCH] of: set dma_mask to point to coherent_dma_mask

[Rob Herring <robherring2@gmail.com>]

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

Platform devices created by DT code don't initialize dma_mask pointer to
anything. Set it to coherent_dma_mask by default if the architecture
code has not set it.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
I think this is at least part of what is needed to fix dma_mask issue
raised by Stefano [1]. Things should work AFAICT with just this, but
I suppose the xgmac driver needs to set the mask as well (not relying
on the default), but some pointing the dma_mask to a valid value is
needed first.

Rob

[1] http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg528236.html

 drivers/of/platform.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index f6dcde2..fce088e 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -215,6 +215,8 @@ static struct platform_device *of_platform_device_create_pdata(
 	dev->archdata.dma_mask = 0xffffffffUL;
 #endif
 	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+	if (!dev->dev.dma_mask)
+		dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
 	dev->dev.bus = &platform_bus_type;
 	dev->dev.platform_data = platform_data;
 
-- 
1.8.1.2