From 6471fc6630a507fd54fdaceceee1ddaf3c917cde Mon Sep 17 00:00:00 2001 From: Kumar Gala Date: Fri, 10 Jun 2011 02:22:06 -0500 Subject: [PATCH] powerpc: Dont require a dma_ops struct to set dma mask The only reason to require a dma_ops struct is to see if it has implemented set_dma_mask. If not we can fall back to setting the mask directly. This resolves an issue with how to sequence the setting of a DMA mask for platform devices. Before we had an issue in that we have no way of setting the DMA mask before the various low level bus notifiers get called that might check it (swiotlb). So now we can do: pdev = platform_device_alloc("foobar", 0); dma_set_mask(&pdev->dev, DMA_BIT_MASK(37)); platform_device_add(pdev); And expect the right thing to happen with the bus notifiers get called via platform_device_add. Acked-by: Greg Kroah-Hartman Signed-off-by: Kumar Gala --- arch/powerpc/kernel/dma.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c index d238c082c3c5..4f0959fbfbee 100644 --- a/arch/powerpc/kernel/dma.c +++ b/arch/powerpc/kernel/dma.c @@ -161,9 +161,7 @@ int dma_set_mask(struct device *dev, u64 dma_mask) if (ppc_md.dma_set_mask) return ppc_md.dma_set_mask(dev, dma_mask); - if (unlikely(dma_ops == NULL)) - return -EIO; - if (dma_ops->set_dma_mask != NULL) + if ((dma_ops != NULL) && (dma_ops->set_dma_mask != NULL)) return dma_ops->set_dma_mask(dev, dma_mask); if (!dev->dma_mask || !dma_supported(dev, dma_mask)) return -EIO; -- 2.39.5