git.openpandora.org
/
pandora-kernel.git
/ blobdiff
commit
grep
author
committer
pickaxe
?
search:
re
summary
|
shortlog
|
log
|
commit
|
commitdiff
|
tree
raw
|
inline
| side by side
Merge branch 'upstream/xen-tracing2' of git://git.kernel.org/pub/scm/linux/kernel...
[pandora-kernel.git]
/
Documentation
/
DMA-API-HOWTO.txt
diff --git
a/Documentation/DMA-API-HOWTO.txt
b/Documentation/DMA-API-HOWTO.txt
index
d568bc2
..
a0b6250
100644
(file)
--- a/
Documentation/DMA-API-HOWTO.txt
+++ b/
Documentation/DMA-API-HOWTO.txt
@@
-613,13
+613,13
@@
to use the dma_sync_*() interfaces.
pass_to_upper_layers(cp->rx_buf);
make_and_setup_new_rx_buf(cp);
} else {
pass_to_upper_layers(cp->rx_buf);
make_and_setup_new_rx_buf(cp);
} else {
- /* Just sync the buffer and give it back
- * to the card.
+ /* CPU should not write to
+ * DMA_FROM_DEVICE-mapped area,
+ * so dma_sync_single_for_device() is
+ * not needed here. It would be required
+ * for DMA_BIDIRECTIONAL mapping if
+ * the memory was modified.
*/
*/
- dma_sync_single_for_device(&cp->dev,
- cp->rx_dma,
- cp->rx_len,
- DMA_FROM_DEVICE);
give_rx_buf_to_card(cp);
}
}
give_rx_buf_to_card(cp);
}
}