staging: comedi: ni_labpc: remove VIRT_TO_BUS dependancy

Use dma_{alloc,free}_coherent() to allocate and free the DMA buffers.
This removes the dependancy on VIRT_TO_BUS.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/Kconfig

@@ -502,7 +502,7 @@ config COMEDI_NI_ATMIO16D
 config COMEDI_NI_LABPC_ISA
 	tristate "NI Lab-PC and compatibles ISA support"
 	select COMEDI_NI_LABPC
-	select COMEDI_NI_LABPC_ISADMA if ISA_DMA_API && VIRT_TO_BUS
+	select COMEDI_NI_LABPC_ISADMA if ISA_DMA_API
 	---help---
 	  Enable support for National Instruments Lab-PC and compatibles
 	  Lab-PC-1200, Lab-PC-1200AI, Lab-PC+.

drivers/staging/comedi/drivers/ni_labpc.h

@@ -36,8 +36,8 @@ struct labpc_boardinfo {
 
 struct labpc_dma_desc {
 	unsigned int chan;	/* DMA channel */
-	u16 *virt_addr;		/* virtual address of DMA buffer */
-	phys_addr_t hw_addr;	/* hardware (bus) address of DMA buffer */
+	void *virt_addr;	/* virtual address of DMA buffer */
+	dma_addr_t hw_addr;	/* hardware (bus) address of DMA buffer */
 	unsigned int size;	/* size of DMA transfer (in bytes) */
 };
 

drivers/staging/comedi/drivers/ni_labpc_isadma.c

@@ -175,14 +175,14 @@ void labpc_init_dma_chan(struct comedi_device *dev, unsigned int dma_chan)
 	if (request_dma(dma_chan, dev->board_name))
 		return;
 
-	dma->virt_addr = kmalloc(dma_buffer_size, GFP_KERNEL | GFP_DMA);
+	dma->virt_addr = dma_alloc_coherent(NULL, dma_buffer_size,
+					    &dma->hw_addr, GFP_KERNEL);
 	if (!dma->virt_addr) {
 		free_dma(dma_chan);
 		return;
 	}
 
 	dma->chan = dma_chan;
-	dma->hw_addr = virt_to_bus(dma->virt_addr);
 
 	dma_flags = claim_dma_lock();
 	disable_dma(dma->chan);
@@ -196,7 +196,9 @@ void labpc_free_dma_chan(struct comedi_device *dev)
 	struct labpc_private *devpriv = dev->private;
 	struct labpc_dma_desc *dma = &devpriv->dma_desc;
 
-	kfree(dma->virt_addr);
+	if (dma->virt_addr)
+		dma_free_coherent(NULL, dma_buffer_size,
+				  dma->virt_addr, dma->hw_addr);
 	if (dma->chan)
 		free_dma(dma->chan);
 }