RE: [PATCH 2/2] OMAP: DMA: clear interrupt status correctly

[Santosh Shilimkar <santosh.shilimkar@ti.com>]

> -----Original Message-----
> From: Adrian Hunter [mailto:adrian.hunter@nokia.com]
> Sent: Tuesday, November 30, 2010 6:54 PM
> To: Tony Lindgren
> Cc: Santosh Shilimkar; Manjunatha GK; Adrian Hunter; linux-omap Mailing
> List
> Subject: [PATCH 2/2] OMAP: DMA: clear interrupt status correctly
>
> From 85934ded48552fde84b083575ac2006f1542324b Mon Sep 17 00:00:00 2001
> From: Adrian Hunter <adrian.hunter@nokia.com>
> Date: Wed, 24 Nov 2010 13:23:21 +0200
> Subject: [PATCH 2/2] 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>
> ---
>  arch/arm/plat-omap/dma.c |    7 +++----
>  1 files changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
> index 6158c99..3300e67 100644
> --- a/arch/arm/plat-omap/dma.c
> +++ b/arch/arm/plat-omap/dma.c
> @@ -49,7 +49,7 @@ 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)
>
> @@ -2010,7 +2010,7 @@ static int omap2_dma_handle_ch(int ch)
>  		printk(KERN_INFO "DMA misaligned error with device %d\n",
>  		       dma_chan[ch].dev_id);
>
> -	dma_write(OMAP2_DMA_CSR_CLEAR_MASK, CSR(ch));
> +	dma_write(status, CSR(ch));
>  	dma_write(1 << ch, IRQSTATUS_L0);
>  	/* read back the register to flush the write */
>  	dma_read(IRQSTATUS_L0);
> @@ -2030,10 +2030,9 @@ static int omap2_dma_handle_ch(int ch)
>  			OMAP_DMA_CHAIN_INCQHEAD(chain_id);
>
>  		status = dma_read(CSR(ch));
> +		dma_write(status, CSR(ch));
>  	}
>
> -	dma_write(status, CSR(ch));
> -
>  	if (likely(dma_chan[ch].callback != NULL))
>  		dma_chan[ch].callback(ch, status, dma_chan[ch].data);
>
> --
> 1.7.0.4