omap: DMA: clear interrupt status correctly

When clearing the DMA channel, clear all status bits.

When handling a DMA interrupt, clear only the interrupt
status bits that have been read and are passed to the
channel's interrupt handler, not every status bit.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: G, Manjunath Kondaiah <manjugk@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/plat-omap/dma.c

@@ -53,7 +53,7 @@ enum { DMA_CHAIN_STARTED, DMA_CHAIN_NOTSTARTED };
 #endif
 
 #define OMAP_DMA_ACTIVE			0x01
-#define OMAP2_DMA_CSR_CLEAR_MASK	0xffe
+#define OMAP2_DMA_CSR_CLEAR_MASK	0xffffffff
 
 #define OMAP_FUNC_MUX_ARM_BASE		(0xfffe1000 + 0xec)
 
@@ -1873,7 +1873,7 @@ static int omap2_dma_handle_ch(int ch)
 		printk(KERN_INFO "DMA misaligned error with device %d\n",
 		       dma_chan[ch].dev_id);
 
-	p->dma_write(OMAP2_DMA_CSR_CLEAR_MASK, CSR, ch);
+	p->dma_write(status, CSR, ch);
 	p->dma_write(1 << ch, IRQSTATUS_L0, ch);
 	/* read back the register to flush the write */
 	p->dma_read(IRQSTATUS_L0, ch);
@@ -1893,10 +1893,9 @@ static int omap2_dma_handle_ch(int ch)
 			OMAP_DMA_CHAIN_INCQHEAD(chain_id);
 
 		status = p->dma_read(CSR, ch);
+		p->dma_write(status, CSR, ch);
 	}
 
-	p->dma_write(status, CSR, ch);
-
 	if (likely(dma_chan[ch].callback != NULL))
 		dma_chan[ch].callback(ch, status, dma_chan[ch].data);