Re: [alsa-devel] [PATCH v4 4/4] ASoC: SAMSUNG: Add I2S0 internal dma driver

On Fri, Jul 1, 2011 at 7:18 AM, Sangbeom Kim sbkim73@samsung.com wrote:

+static void idma_control(int op) +{

• u32 val = readl(idma.regs + I2SAHB);
• spin_lock(&idma.lock);
• switch (op) {
• case LPAM_DMA_START:
• val |= (AHB_INTENLVL0 | AHB_DMAEN);
• break;
• case LPAM_DMA_STOP:
• val &= ~(AHB_INTENLVL0 | AHB_DMAEN);
• break;
• default:
• return;

Need to release the lock before return. This is not the showstopper for this revision.

• }
• writel(val, idma.regs + I2SAHB);
• spin_unlock(&idma.lock);

+}

......

+static irqreturn_t iis_irq(int irqno, void *dev_id) +{

• struct idma_ctrl *prtd = (struct idma_ctrl *)dev_id;
• u32 iiscon, iisahb, val, addr;
• iisahb  = readl(idma.regs + I2SAHB);
• iiscon  = readl(idma.regs + I2SCON);
• val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0;
• if (val) {
• iisahb |= val;
• writel(iisahb, idma.regs + I2SAHB);
• addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr;
• addr += prtd->periodsz;
• addr %= prtd->period;
• addr += idma.lp_tx_addr;

Dear, out of 4 revisions, 3(including current) got it wrong at this important point. Ok write it like below               addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr;               addr += prtd->periodsz;               addr %= (prtd->end - prtd->start); // <------ Note               addr += idma.lp_tx_addr;

• writel(addr, idma.regs + I2SLVL0ADDR);
• if (prtd->cb)
• prtd->cb(prtd->token, prtd->period);
• }
• return IRQ_HANDLED;

+}