[PATCH] ARM: OMAP: dma progress meter function in dma.c

The following patch adds a new fuction in file dma.c:

- omap_get_dma_src_addr_counter

This function returns the value of the DMA source counter register.
It can be used to show the progress of the dma transfer for a given channel.

arch/arm/plat-omap/dma.c

@@ -983,6 +983,16 @@ dma_addr_t omap_get_dma_dst_pos(int lch)
 	(omap_readw(OMAP_DMA_CDSA_U(lch)) << 16));
 }
 
+/*
+ * Returns current source transfer counting for the given DMA channel.
+ * Can be used to monitor the progress of a transfer inside a  block.
+ * It must be called with disabled interrupts.
+ */
+int omap_get_dma_src_addr_counter(int lch)
+{
+	return (dma_addr_t) omap_readw(OMAP_DMA_CSAC(lch));
+}
+
 int omap_dma_running(void)
 {
 	int lch;
@@ -1076,6 +1086,7 @@ arch_initcall(omap_init_dma);
 
 EXPORT_SYMBOL(omap_get_dma_src_pos);
 EXPORT_SYMBOL(omap_get_dma_dst_pos);
+EXPORT_SYMBOL(omap_get_dma_src_addr_counter);
 EXPORT_SYMBOL(omap_clear_dma);
 EXPORT_SYMBOL(omap_set_dma_priority);
 EXPORT_SYMBOL(omap_request_dma);

include/asm-arm/arch-omap/dma.h

@@ -240,6 +240,7 @@ extern void omap_dma_unlink_lch (int lch_head, int lch_queue);
 
 extern dma_addr_t omap_get_dma_src_pos(int lch);
 extern dma_addr_t omap_get_dma_dst_pos(int lch);
+extern int omap_get_dma_src_addr_counter(int lch);
 extern void omap_clear_dma(int lch);
 extern int omap_dma_running(void);