dma-mapping: remove the set_dma_mask method

Signed-off-by: Christoph Hellwig <hch@lst.de>

arch/powerpc/kernel/dma.c

@@ -316,10 +316,6 @@ EXPORT_SYMBOL(dma_set_coherent_mask);
 
 int __dma_set_mask(struct device *dev, u64 dma_mask)
 {
-	const struct dma_map_ops *dma_ops = get_dma_ops(dev);
-
-	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;
 	*dev->dma_mask = dma_mask;

include/linux/dma-mapping.h

@@ -127,7 +127,6 @@ struct dma_map_ops {
 				   enum dma_data_direction dir);
 	int (*mapping_error)(struct device *dev, dma_addr_t dma_addr);
 	int (*dma_supported)(struct device *dev, u64 mask);
-	int (*set_dma_mask)(struct device *dev, u64 mask);
 #ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
 	u64 (*get_required_mask)(struct device *dev);
 #endif
@@ -563,11 +562,6 @@ static inline int dma_supported(struct device *dev, u64 mask)
 #ifndef HAVE_ARCH_DMA_SET_MASK
 static inline int dma_set_mask(struct device *dev, u64 mask)
 {
-	const struct dma_map_ops *ops = get_dma_ops(dev);
-
-	if (ops->set_dma_mask)
-		return ops->set_dma_mask(dev, mask);
-
 	if (!dev->dma_mask || !dma_supported(dev, mask))
 		return -EIO;
 	*dev->dma_mask = mask;