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-rw-r--r--Documentation/DMA-API.txt9
1 files changed, 4 insertions, 5 deletions
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index b462bb149543..52441694fe03 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -170,16 +170,15 @@ Returns: 0 if successful and a negative error if not.
170u64 170u64
171dma_get_required_mask(struct device *dev) 171dma_get_required_mask(struct device *dev)
172 172
173After setting the mask with dma_set_mask(), this API returns the 173This API returns the mask that the platform requires to
174actual mask (within that already set) that the platform actually 174operate efficiently. Usually this means the returned mask
175requires to operate efficiently. Usually this means the returned mask
176is the minimum required to cover all of memory. Examining the 175is the minimum required to cover all of memory. Examining the
177required mask gives drivers with variable descriptor sizes the 176required mask gives drivers with variable descriptor sizes the
178opportunity to use smaller descriptors as necessary. 177opportunity to use smaller descriptors as necessary.
179 178
180Requesting the required mask does not alter the current mask. If you 179Requesting the required mask does not alter the current mask. If you
181wish to take advantage of it, you should issue another dma_set_mask() 180wish to take advantage of it, you should issue a dma_set_mask()
182call to lower the mask again. 181call to set the mask to the value returned.
183 182
184 183
185Part Id - Streaming DMA mappings 184Part Id - Streaming DMA mappings