dma-mapping: dma-mapping.h: add dma_set_coherent_mask

dma_set_coherent_mask corresponds to pci_set_consistent_dma_mask.  This is
necessary to move to the generic device model DMA API from the PCI bus
specific API in the long term.

dma_set_coherent_mask works in the exact same way that
pci_set_consistent_dma_mask does.  So this patch also changes
pci_set_consistent_dma_mask to call dma_set_coherent_mask.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@suse.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index c5ac9d49cc0..ca32ed78b05 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -127,6 +127,14 @@ static inline u64 dma_get_mask(struct device *dev)
         return DMA_BIT_MASK(32);
 }
 
+static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
+{
+        if (!dma_supported(dev, mask))
+                return -EIO;
+        dev->coherent_dma_mask = mask;
+        return 0;
+}
+
 extern u64 dma_get_required_mask(struct device *dev);
 
 static inline unsigned int dma_get_max_seg_size(struct device *dev)