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ARM: S3C64XX: DMA: Callback with correct buffer pointer

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buffdone callback should be called per buffer request with pointer
to the latest serviced request.
'next' should point to the one next to currently active.

Signed-off-by: Jassi Brar <jassi.brar@samsung.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This commit is contained in:
Jassi Brar 2009-11-05 13:44:33 +09:00 committed by Ben Dooks
parent 7507f39c57
commit 9b08284bf2
1 changed files with 28 additions and 1 deletions
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29
arch/arm/plat-s3c64xx/dma.c
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@ -576,6 +576,7 @@ static irqreturn_t s3c64xx_dma_irq(int irq, void *pw)
errstat = readl(dmac->regs + PL080_ERR_STATUS);
for (offs = 0, bit = 1; offs < 8; offs++, bit <<= 1) {
struct s3c64xx_dma_buff *buff;
if (!(errstat & bit) && !(tcstat & bit))
continue;
@ -591,7 +592,33 @@ static irqreturn_t s3c64xx_dma_irq(int irq, void *pw)
if (errstat & bit)
writel(bit, dmac->regs + PL080_ERR_CLEAR);
s3c64xx_dma_bufffdone(chan, chan->curr, res);
/* 'next' points to the buffer that is next to the
* currently active buffer.
* For CIRCULAR queues, 'next' will be same as 'curr'
* when 'end' is the active buffer.
*/
buff = chan->curr;
while (buff && buff != chan->next
&& buff->next != chan->next)
buff = buff->next;
if (!buff)
BUG();
if (buff == chan->next)
buff = chan->end;
s3c64xx_dma_bufffdone(chan, buff, res);
/* Update 'next' */
buff = chan->next;
if (chan->next == chan->end) {
chan->next = chan->curr;
if (!(chan->flags & S3C2410_DMAF_CIRCULAR))
chan->end = NULL;
} else {
chan->next = buff->next;
}
}
return IRQ_HANDLED;