ARM: OMAP: Sleep is prevented when no LCD is attached

We have to make sure that the LCD DMA external destination bit is
cleared by default, otherwise OMAP won't sleep.

Signed-off-by: Imre Deak <imre.deak@solidboot.com>
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index 9eddc9507147..9948d7a26339 100644
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -1339,6 +1339,14 @@ static int __init omap_init_dma(void)
                         dma_chan_count = 16;
                 } else
                         dma_chan_count = 9;
+                if (cpu_is_omap16xx()) {
+                        u16 w;
+
+                        /* this would prevent OMAP sleep */
+                        w = omap_readw(OMAP1610_DMA_LCD_CTRL);
+                        w &= ~(1 << 8);
+                        omap_writew(w, OMAP1610_DMA_LCD_CTRL);
+                }
         } else if (cpu_is_omap24xx()) {
                 u8 revision = omap_readb(OMAP_DMA4_REVISION);
                 printk(KERN_INFO "OMAP DMA hardware revision %d.%d\n",