From: Mathias Nyman Date: Mon, 25 Oct 2010 14:35:24 +0000 (+0000) Subject: omap: dma: Add read-back to DMA interrupt handler to avoid spuriousinterrupts X-Git-Tag: firefly_0821_release~7613^2~3424^2~2 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e860e6da96f5a320a752da232e03d7bf885710b7;p=firefly-linux-kernel-4.4.55.git omap: dma: Add read-back to DMA interrupt handler to avoid spuriousinterrupts Flush the writes to IRQSTATUS_L0 register in the DMA interrupt handler by reading the register directly after write. This prevents the spurious DMA interrupts noted when using VDD_OPP 1 Signed-off-by: Mathias Nyman Acked-by: Santosh Shilimkar Signed-off-by: Tony Lindgren --- diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c index f5c5b8da9a87..2c2826571d45 100644 --- a/arch/arm/plat-omap/dma.c +++ b/arch/arm/plat-omap/dma.c @@ -1983,6 +1983,8 @@ static int omap2_dma_handle_ch(int ch) dma_write(OMAP2_DMA_CSR_CLEAR_MASK, CSR(ch)); dma_write(1 << ch, IRQSTATUS_L0); + /* read back the register to flush the write */ + dma_read(IRQSTATUS_L0); /* If the ch is not chained then chain_id will be -1 */ if (dma_chan[ch].chain_id != -1) {