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Diffstat (limited to 'arch/arm/plat-omap/dma.c')
-rw-r--r--arch/arm/plat-omap/dma.c22
1 files changed, 21 insertions, 1 deletions
diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index c22217c2ee5..002fb4d96bb 100644
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -1034,6 +1034,18 @@ dma_addr_t omap_get_dma_src_pos(int lch)
if (IS_DMA_ERRATA(DMA_ERRATA_3_3) && offset == 0)
offset = p->dma_read(CSAC, lch);
+ if (!cpu_is_omap15xx()) {
+ /*
+ * CDAC == 0 indicates that the DMA transfer on the channel has
+ * not been started (no data has been transferred so far).
+ * Return the programmed source start address in this case.
+ */
+ if (likely(p->dma_read(CDAC, lch)))
+ offset = p->dma_read(CSAC, lch);
+ else
+ offset = p->dma_read(CSSA, lch);
+ }
+
if (cpu_class_is_omap1())
offset |= (p->dma_read(CSSA, lch) & 0xFFFF0000);
@@ -1062,8 +1074,16 @@ dma_addr_t omap_get_dma_dst_pos(int lch)
* omap 3.2/3.3 erratum: sometimes 0 is returned if CSAC/CDAC is
* read before the DMA controller finished disabling the channel.
*/
- if (!cpu_is_omap15xx() && offset == 0)
+ if (!cpu_is_omap15xx() && offset == 0) {
offset = p->dma_read(CDAC, lch);
+ /*
+ * CDAC == 0 indicates that the DMA transfer on the channel has
+ * not been started (no data has been transferred so far).
+ * Return the programmed destination start address in this case.
+ */
+ if (unlikely(!offset))
+ offset = p->dma_read(CDSA, lch);
+ }
if (cpu_class_is_omap1())
offset |= (p->dma_read(CDSA, lch) & 0xFFFF0000);