From 56f55f8b58a02e95b401cb50df05086cabeaeeb5 Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 25 Sep 2008 20:59:12 +0100 Subject: [ARM] dma: provide a better dma_map_page() implementation We can translate a struct page directly to a DMA address using page_to_dma(). No need to use page_address() followed by virt_to_dma(). Signed-off-by: Russell King --- arch/arm/common/dmabounce.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'arch/arm/common/dmabounce.c') diff --git a/arch/arm/common/dmabounce.c b/arch/arm/common/dmabounce.c index 35c72bcf3d0b..c7f23ced0a36 100644 --- a/arch/arm/common/dmabounce.c +++ b/arch/arm/common/dmabounce.c @@ -412,6 +412,19 @@ dma_map_single(struct device *dev, void *ptr, size_t size, return dma_addr; } +dma_addr_t dma_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir) +{ + dev_dbg(dev, "%s(page=%p,off=%#lx,size=%zx,dir=%x)\n", + __func__, page, offset, size, dir); + + BUG_ON(dir == DMA_NONE); + + return map_single(dev, page_address(page) + offset, size, dir); +} +EXPORT_SYMBOL(dma_map_page); + /* * see if a mapped address was really a "safe" buffer and if so, copy * the data from the safe buffer back to the unsafe buffer and free up -- cgit