ASoC: dwc: Iterate over all channels

The Designware core can be configured with up to four stereo channels.
Each stereo channel is individually configured so, when the driver's
hw_params call is made, each requested stereo channel has to be
programmed.
Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/dwc/designware_i2s.c

@@ -209,16 +209,9 @@ static int dw_i2s_hw_params(struct snd_pcm_substream *substream,
 
 	switch (config->chan_nr) {
 	case EIGHT_CHANNEL_SUPPORT:
-		ch_reg = 3;
-		break;
 	case SIX_CHANNEL_SUPPORT:
-		ch_reg = 2;
-		break;
 	case FOUR_CHANNEL_SUPPORT:
-		ch_reg = 1;
-		break;
 	case TWO_CHANNEL_SUPPORT:
-		ch_reg = 0;
 		break;
 	default:
 		dev_err(dev->dev, "channel not supported\n");
@@ -227,19 +220,23 @@ static int dw_i2s_hw_params(struct snd_pcm_substream *substream,
 
 	i2s_disable_channels(dev, substream->stream);
 
+	for (ch_reg = 0; ch_reg < (config->chan_nr / 2); ch_reg++) {
 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-		i2s_write_reg(dev->i2s_base, TCR(ch_reg), xfer_resolution);
+			i2s_write_reg(dev->i2s_base, TCR(ch_reg),
+				      xfer_resolution);
 			i2s_write_reg(dev->i2s_base, TFCR(ch_reg), 0x02);
 			irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
 			i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x30);
 			i2s_write_reg(dev->i2s_base, TER(ch_reg), 1);
 		} else {
-		i2s_write_reg(dev->i2s_base, RCR(ch_reg), xfer_resolution);
+			i2s_write_reg(dev->i2s_base, RCR(ch_reg),
+				      xfer_resolution);
 			i2s_write_reg(dev->i2s_base, RFCR(ch_reg), 0x07);
 			irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
 			i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x03);
 			i2s_write_reg(dev->i2s_base, RER(ch_reg), 1);
 		}
+	}
 
 	i2s_write_reg(dev->i2s_base, CCR, ccr);