diff --git a/arch/arm/plat-s3c64xx/dma.c b/arch/arm/plat-s3c64xx/dma.c index a94281bb84d6..7d12eb8fa58d 100644 --- a/arch/arm/plat-s3c64xx/dma.c +++ b/arch/arm/plat-s3c64xx/dma.c @@ -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;