dma: Add support to program MIC x100 status descriptiors

The MIC X100 DMA engine has a special status descriptor which writes
an 8 byte value to a destination location.  This is used to signal
completion of all DMA descriptors prior to the status descriptor.
This patch add a new DMA engine API which enables updating a
destination address with an 8 byte immediate data value.

Reviewed-by: Nikhil Rao <nikhil.rao@intel.com>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Lawrynowicz, Jacek <jacek.lawrynowicz@intel.com>
Signed-off-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Siva Yerramreddy <yshivakrishna@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 7ea9184eaa13..c47c68e535e8 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -645,6 +645,7 @@ enum dmaengine_alignment {
  *	The function takes a buffer of size buf_len. The callback function will
  *	be called after period_len bytes have been transferred.
  * @device_prep_interleaved_dma: Transfer expression in a generic way.
+ * @device_prep_dma_imm_data: DMA's 8 byte immediate data to the dst address
  * @device_config: Pushes a new configuration to a channel, return 0 or an error
  *	code
  * @device_pause: Pauses any transfer happening on a channel. Returns
@@ -727,6 +728,9 @@ struct dma_device {
 	struct dma_async_tx_descriptor *(*device_prep_interleaved_dma)(
 		struct dma_chan *chan, struct dma_interleaved_template *xt,
 		unsigned long flags);
+	struct dma_async_tx_descriptor *(*device_prep_dma_imm_data)(
+		struct dma_chan *chan, dma_addr_t dst, u64 data,
+		unsigned long flags);
 
 	int (*device_config)(struct dma_chan *chan,
 			     struct dma_slave_config *config);