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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /kernel/dma/dummy.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'kernel/dma/dummy.c')
-rw-r--r--kernel/dma/dummy.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/kernel/dma/dummy.c b/kernel/dma/dummy.c
new file mode 100644
index 0000000000..b492d59ac7
--- /dev/null
+++ b/kernel/dma/dummy.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Dummy DMA ops that always fail.
+ */
+#include <linux/dma-map-ops.h>
+
+static int dma_dummy_mmap(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs)
+{
+ return -ENXIO;
+}
+
+static dma_addr_t dma_dummy_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ return DMA_MAPPING_ERROR;
+}
+
+static int dma_dummy_map_sg(struct device *dev, struct scatterlist *sgl,
+ int nelems, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ return -EINVAL;
+}
+
+static int dma_dummy_supported(struct device *hwdev, u64 mask)
+{
+ return 0;
+}
+
+const struct dma_map_ops dma_dummy_ops = {
+ .mmap = dma_dummy_mmap,
+ .map_page = dma_dummy_map_page,
+ .map_sg = dma_dummy_map_sg,
+ .dma_supported = dma_dummy_supported,
+};