OMAP: McBSP: Let element DMA mode hit retention also

The device no longer hits retention if element DMA
mode is taken for at least the duration of the
serial console timeout. Force element DMA mode to
shut down through smartidle.

Signed-off-by: Eero Nurkkala <ext-eero.nurkkala@nokia.com>
Acked-by: Eduardo Valentin <eduardo.valentin@nokia.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/arch/arm/plat-omap/mcbsp.c b/arch/arm/plat-omap/mcbsp.c
index 56a56887ded..b63a7209b41 100644
--- a/arch/arm/plat-omap/mcbsp.c
+++ b/arch/arm/plat-omap/mcbsp.c
@@ -343,6 +343,15 @@ static inline void omap34xx_mcbsp_free(struct omap_mcbsp *mcbsp)
 
                 syscon = OMAP_MCBSP_READ(mcbsp->io_base, SYSCON);
                 syscon &= ~(ENAWAKEUP | SIDLEMODE(0x03) | CLOCKACTIVITY(0x03));
+                /*
+                 * HW bug workaround - If no_idle mode is taken, we need to
+                 * go to smart_idle before going to always_idle, or the
+                 * device will not hit retention anymore.
+                 */
+                syscon |= SIDLEMODE(0x02);
+                OMAP_MCBSP_WRITE(mcbsp->io_base, SYSCON, syscon);
+
+                syscon &= ~(SIDLEMODE(0x03));
                 OMAP_MCBSP_WRITE(mcbsp->io_base, SYSCON, syscon);
 
                 OMAP_MCBSP_WRITE(mcbsp->io_base, WAKEUPEN, 0);