diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 2dc21cbeb3049a0d9a2ffa2d0ee27271c66d1c62..0ebfafbd338ca56fc89f781c2848a9c16b81cb6d 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -24,6 +24,8 @@ enum dma_data_direction { #define DMA_28BIT_MASK 0x000000000fffffffULL #define DMA_24BIT_MASK 0x0000000000ffffffULL +#define DMA_MASK_NONE 0x0ULL + static inline int valid_dma_direction(int dma_direction) { return ((dma_direction == DMA_BIDIRECTIONAL) || @@ -31,6 +33,11 @@ static inline int valid_dma_direction(int dma_direction) (dma_direction == DMA_FROM_DEVICE)); } +static inline int is_device_dma_capable(struct device *dev) +{ + return dev->dma_mask != NULL && *dev->dma_mask != DMA_MASK_NONE; +} + #ifdef CONFIG_HAS_DMA #include #else