serial: sh-sci: Use sg_dma_len() and sg_dma_address()

Convert the dmaengine code in sh-sci.c from
directly accessing the struct scatterlist members
length, dma_length and dma_address to using the
macros sg_dma_len() and sg_dma_address().

Makes the code build for ARM.

Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

drivers/serial/sh-sci.c

@@ -916,10 +916,10 @@ static void sci_dma_tx_complete(void *arg)
 
 	spin_lock_irqsave(&port->lock, flags);
 
-	xmit->tail += s->sg_tx.length;
+	xmit->tail += sg_dma_len(&s->sg_tx);
 	xmit->tail &= UART_XMIT_SIZE - 1;
 
-	port->icount.tx += s->sg_tx.length;
+	port->icount.tx += sg_dma_len(&s->sg_tx);
 
 	async_tx_ack(s->desc_tx);
 	s->cookie_tx = -EINVAL;
@@ -1134,14 +1134,13 @@ static void work_fn_tx(struct work_struct *work)
 	 */
 	spin_lock_irq(&port->lock);
 	sg->offset = xmit->tail & (UART_XMIT_SIZE - 1);
-	sg->dma_address = (sg_dma_address(sg) & ~(UART_XMIT_SIZE - 1)) +
+	sg_dma_address(sg) = (sg_dma_address(sg) & ~(UART_XMIT_SIZE - 1)) +
 		sg->offset;
-	sg->length = min((int)CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
+	sg_dma_len(sg) = min((int)CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
 		CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
-	sg->dma_length = sg->length;
 	spin_unlock_irq(&port->lock);
 
-	BUG_ON(!sg->length);
+	BUG_ON(!sg_dma_len(sg));
 
 	desc = chan->device->device_prep_slave_sg(chan,
 			sg, s->sg_len_tx, DMA_TO_DEVICE,
@@ -1342,8 +1341,7 @@ static void sci_request_dma(struct uart_port *port)
 			sg_init_table(sg, 1);
 			sg_set_page(sg, virt_to_page(buf[i]), s->buf_len_rx,
 				    (int)buf[i] & ~PAGE_MASK);
-			sg->dma_address = dma[i];
-			sg->dma_length = sg->length;
+			sg_dma_address(sg) = dma[i];
 		}
 
 		INIT_WORK(&s->work_rx, work_fn_rx);