1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 * Dummy DMA ops that always fail.
 4 */
 5#include <linux/dma-map-ops.h>
 6
 7static int dma_dummy_mmap(struct device *dev, struct vm_area_struct *vma,
 8		void *cpu_addr, dma_addr_t dma_addr, size_t size,
 9		unsigned long attrs)
10{
11	return -ENXIO;
12}
13
14static dma_addr_t dma_dummy_map_page(struct device *dev, struct page *page,
15		unsigned long offset, size_t size, enum dma_data_direction dir,
16		unsigned long attrs)
17{
18	return DMA_MAPPING_ERROR;
19}
 
 
 
 
 
 
 
 
 
20
21static int dma_dummy_map_sg(struct device *dev, struct scatterlist *sgl,
22		int nelems, enum dma_data_direction dir,
23		unsigned long attrs)
24{
25	return -EINVAL;
26}
27
 
 
 
 
 
 
 
 
 
 
28static int dma_dummy_supported(struct device *hwdev, u64 mask)
29{
30	return 0;
31}
32
33const struct dma_map_ops dma_dummy_ops = {
34	.mmap                   = dma_dummy_mmap,
35	.map_page               = dma_dummy_map_page,
 
36	.map_sg                 = dma_dummy_map_sg,
 
37	.dma_supported          = dma_dummy_supported,
38};

 1// SPDX-License-Identifier: GPL-2.0
 2/*
 3 * Dummy DMA ops that always fail.
 4 */
 5#include <linux/dma-map-ops.h>
 6
 7static int dma_dummy_mmap(struct device *dev, struct vm_area_struct *vma,
 8		void *cpu_addr, dma_addr_t dma_addr, size_t size,
 9		unsigned long attrs)
10{
11	return -ENXIO;
12}
13
14static dma_addr_t dma_dummy_map_page(struct device *dev, struct page *page,
15		unsigned long offset, size_t size, enum dma_data_direction dir,
16		unsigned long attrs)
17{
18	return DMA_MAPPING_ERROR;
19}
20static void dma_dummy_unmap_page(struct device *dev, dma_addr_t dma_handle,
21		size_t size, enum dma_data_direction dir, unsigned long attrs)
22{
23	/*
24	 * Dummy ops doesn't support map_page, so unmap_page should never be
25	 * called.
26	 */
27	WARN_ON_ONCE(true);
28}
29
30static int dma_dummy_map_sg(struct device *dev, struct scatterlist *sgl,
31		int nelems, enum dma_data_direction dir,
32		unsigned long attrs)
33{
34	return -EINVAL;
35}
36
37static void dma_dummy_unmap_sg(struct device *dev, struct scatterlist *sgl,
38		int nelems, enum dma_data_direction dir,
39		unsigned long attrs)
40{
41	/*
42	 * Dummy ops doesn't support map_sg, so unmap_sg should never be called.
43	 */
44	WARN_ON_ONCE(true);
45}
46
47static int dma_dummy_supported(struct device *hwdev, u64 mask)
48{
49	return 0;
50}
51
52const struct dma_map_ops dma_dummy_ops = {
53	.mmap                   = dma_dummy_mmap,
54	.map_page               = dma_dummy_map_page,
55	.unmap_page             = dma_dummy_unmap_page,
56	.map_sg                 = dma_dummy_map_sg,
57	.unmap_sg               = dma_dummy_unmap_sg,
58	.dma_supported          = dma_dummy_supported,
59};