dmaengine: allow dma support for async_tx to be toggled

Provide a config option for blocking the allocation of dma channels to
the async_tx api.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 48ea59e7967..3b3c01b6f1e 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -98,6 +98,17 @@ config NET_DMA
           Say Y here if you enabled INTEL_IOATDMA or FSL_DMA, otherwise
           say N.
 
+config ASYNC_TX_DMA
+        bool "Async_tx: Offload support for the async_tx api"
+        depends on DMA_ENGINE
+        help
+          This allows the async_tx api to take advantage of offload engines for
+          memcpy, memset, xor, and raid6 p+q operations.  If your platform has
+          a dma engine that can perform raid operations and you have enabled
+          MD_RAID456 say Y.
+
+          If unsure, say N.
+
 config DMATEST
         tristate "DMA Test client"
         depends on DMA_ENGINE