ARM: OMAP: DMA: Add support for DMA channel self linking on OMAP1510

Implement DMA channel self linking on OMAP1510 using AUTO_INIT and REPEAT
flags of the DMA CCR register.

Created against linux-2.6.31-rc5.

Tested on Amstrad Delta.
Signed-off-by: NJanusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

arch/arm/plat-omap/dma.c

@@ -1125,6 +1125,11 @@ int omap_dma_running(void)
 void omap_dma_link_lch(int lch_head, int lch_queue)
 {
 	if (omap_dma_in_1510_mode()) {
+		if (lch_head == lch_queue) {
+			dma_write(dma_read(CCR(lch_head)) | (3 << 8),
+								CCR(lch_head));
+			return;
+		}
 		printk(KERN_ERR "DMA linking is not supported in 1510 mode\n");
 		BUG();
 		return;
@@ -1147,6 +1152,11 @@ EXPORT_SYMBOL(omap_dma_link_lch);
 void omap_dma_unlink_lch(int lch_head, int lch_queue)
 {
 	if (omap_dma_in_1510_mode()) {
+		if (lch_head == lch_queue) {
+			dma_write(dma_read(CCR(lch_head)) & ~(3 << 8),
+								CCR(lch_head));
+			return;
+		}
 		printk(KERN_ERR "DMA linking is not supported in 1510 mode\n");
 		BUG();
 		return;