dmaengine: call acpi_dma_request_slave_channel as well

The slave device could be enumerated by ACPI. In that case the
dma_request_slave_channel should use the acpi_dma_request_slave_channel()
helper.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/dmaengine.c

@@ -62,6 +62,8 @@
 #include <linux/rculist.h>
 #include <linux/idr.h>
 #include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/acpi_dma.h>
 #include <linux/of_dma.h>
 
 static DEFINE_MUTEX(dma_list_mutex);
@@ -564,6 +566,10 @@ struct dma_chan *dma_request_slave_channel(struct device *dev, char *name)
 	if (dev->of_node)
 		return of_dma_request_slave_channel(dev->of_node, name);
 
+	/* If device was enumerated by ACPI get slave info from here */
+	if (ACPI_HANDLE(dev))
+		return acpi_dma_request_slave_chan_by_name(dev, name);
+
 	return NULL;
 }
 EXPORT_SYMBOL_GPL(dma_request_slave_channel);