| 1 | |
| 2 | |
| 3 | * Dummy DMA ops that always fail.
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| 4 |
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| 5 | #include <linux/dma-map-ops.h>
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| 6 |
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| 7 | static int dma_dummy_mmap(struct device *dev, struct vm_area_struct *vma,
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| 8 | void *cpu_addr, dma_addr_t dma_addr, size_t size,
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| 9 | unsigned long attrs)
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| 10 | {
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| 11 | return -ENXIO;
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| 12 | }
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| 13 |
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| 14 | static dma_addr_t dma_dummy_map_phys(struct device *dev, phys_addr_t phys,
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| 15 | size_t size, enum dma_data_direction dir, unsigned long attrs)
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| 16 | {
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| 17 | return DMA_MAPPING_ERROR;
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| 18 | }
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| 19 | static void dma_dummy_unmap_phys(struct device *dev, dma_addr_t dma_handle,
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| 20 | size_t size, enum dma_data_direction dir, unsigned long attrs)
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| 21 | {
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| 22 | |
| 23 | * Dummy ops doesn't support map_phys, so unmap_page should never be
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| 24 | * called.
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| 25 |
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| 26 | WARN_ON_ONCE(true);
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| 27 | }
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| 28 |
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| 29 | static int dma_dummy_map_sg(struct device *dev, struct scatterlist *sgl,
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| 30 | int nelems, enum dma_data_direction dir,
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| 31 | unsigned long attrs)
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| 32 | {
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| 33 | return -EINVAL;
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| 34 | }
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| 35 |
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| 36 | static void dma_dummy_unmap_sg(struct device *dev, struct scatterlist *sgl,
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| 37 | int nelems, enum dma_data_direction dir,
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| 38 | unsigned long attrs)
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| 39 | {
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| 40 | |
| 41 | * Dummy ops doesn't support map_sg, so unmap_sg should never be called.
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| 42 |
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| 43 | WARN_ON_ONCE(true);
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| 44 | }
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| 45 |
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| 46 | static int dma_dummy_supported(struct device *hwdev, u64 mask)
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| 47 | {
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| 48 | return 0;
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| 49 | }
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| 50 |
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| 51 | const struct dma_map_ops dma_dummy_ops = {
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| 52 | .mmap = dma_dummy_mmap,
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| 53 | .map_phys = dma_dummy_map_phys,
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| 54 | .unmap_phys = dma_dummy_unmap_phys,
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| 55 | .map_sg = dma_dummy_map_sg,
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| 56 | .unmap_sg = dma_dummy_unmap_sg,
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| 57 | .dma_supported = dma_dummy_supported,
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| 58 | };
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