static irqreturn_t i2s_irq_handler(int irq, void *dev_id)
{
struct dw_i2s_dev *dev = dev_id;
bool irq_valid = false;
u32 isr[4];
int i;
for (i = 0; i < 4; i++)
isr[i] = i2s_read_reg(dev->i2s_base, ISR(i));
i2s_clear_irqs(dev, SNDRV_PCM_STREAM_PLAYBACK);
i2s_clear_irqs(dev, SNDRV_PCM_STREAM_CAPTURE);
for (i = 0; i < 4; i++) {
/*
* Check if TX fifo is empty. If empty fill FIFO with samples
* NOTE: Only two channels supported
*/
if ((isr[i] & ISR_TXFE) && (i == 0) && dev->use_pio) {
dw_pcm_push_tx(dev);
irq_valid = true;
}
/*
* Data available. Retrieve samples from FIFO
* NOTE: Only two channels supported
*/
if ((isr[i] & ISR_RXDA) && (i == 0) && dev->use_pio) {
dw_pcm_pop_rx(dev);
irq_valid = true;
}
/* Error Handling: TX */
if (isr[i] & ISR_TXFO) {
dev_err(dev->dev, "TX overrun (ch_id=%d)\n", i);
irq_valid = true;
}
/* Error Handling: TX */
if (isr[i] & ISR_RXFO) {
dev_err(dev->dev, "RX overrun (ch_id=%d)\n", i);
irq_valid = true;
}
}
if (irq_valid)
return IRQ_HANDLED;
else
return IRQ_NONE;
}
static void i2s_stop(struct dw_i2s_dev *dev,
struct snd_pcm_substream *substream)
{
u32 i = 0, irq;
i2s_clear_irqs(dev, substream->stream);
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
i2s_write_reg(dev->i2s_base, ITER, 0);
for (i = 0; i < 4; i++) {
irq = i2s_read_reg(dev->i2s_base, IMR(i));
i2s_write_reg(dev->i2s_base, IMR(i), irq | 0x30);
}
} else {
i2s_write_reg(dev->i2s_base, IRER, 0);
for (i = 0; i < 4; i++) {
irq = i2s_read_reg(dev->i2s_base, IMR(i));
i2s_write_reg(dev->i2s_base, IMR(i), irq | 0x03);
}
}
if (!dev->active) {
i2s_write_reg(dev->i2s_base, CER, 0);
i2s_write_reg(dev->i2s_base, IER, 0);
}
}
static void i2s_stop(struct dw_i2s_dev *dev,
struct snd_pcm_substream *substream)
{
i2s_clear_irqs(dev, substream->stream);
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
i2s_write_reg(dev->i2s_base, ITER, 0);
else
i2s_write_reg(dev->i2s_base, IRER, 0);
i2s_disable_irqs(dev, substream->stream, 8);
if (!dev->active) {
i2s_write_reg(dev->i2s_base, CER, 0);
i2s_write_reg(dev->i2s_base, IER, 0);
}
}