dmaengine/dma_slave: introduce inline wrappers

Add inline wrappers for device_prep_slave_sg() and device_prep_dma_cyclic()
interfaces to hide new parameter from current users of affected interfaces.
Convert current users to use new wrappers instead of direct calls.
Suggested by Russell King [https://lkml.org/lkml/2012/2/3/269].

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 715babf..03d68b7 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -622,6 +622,22 @@
 	return chan->device->device_prep_slave_sg(chan, &sg, 1, dir, flags);
 }
 
+static inline struct dma_async_tx_descriptor *dmaengine_prep_slave_sg(
+	struct dma_chan *chan, struct scatterlist *sgl,	unsigned int sg_len,
+	enum dma_transfer_direction dir, unsigned long flags)
+{
+	return chan->device->device_prep_slave_sg(chan, sgl, sg_len,
+						  dir, flags);
+}
+
+static inline struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
+		struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
+		size_t period_len, enum dma_transfer_direction dir)
+{
+	return chan->device->device_prep_dma_cyclic(chan, buf_addr, buf_len,
+							period_len, dir);
+}
+
 static inline int dmaengine_terminate_all(struct dma_chan *chan)
 {
 	return dmaengine_device_control(chan, DMA_TERMINATE_ALL, 0);