ASoC: fsi: Modify over/under run error settlement

In current FSI driver, playback function cares only overrun,
and capture function cares only underrun.

But playback function should had cared about underrun,
and capture function should had cared about overrun too.

Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/sh/fsi.c b/sound/soc/sh/fsi.c
index 3c36d24..993abb7 100644
--- a/sound/soc/sh/fsi.c
+++ b/sound/soc/sh/fsi.c
@@ -388,7 +388,7 @@
 }
 
 /* playback interrupt */
-static int fsi_data_push(struct fsi_priv *fsi)
+static int fsi_data_push(struct fsi_priv *fsi, int startup)
 {
 	struct snd_pcm_runtime *runtime;
 	struct snd_pcm_substream *substream = NULL;
@@ -397,7 +397,7 @@
 	int fifo_free;
 	int width;
 	u8 *start;
-	int i, ret, over_period;
+	int i, over_period;
 
 	if (!fsi			||
 	    !fsi->substream		||
@@ -453,24 +453,26 @@
 
 	fsi->byte_offset += send * width;
 
-	ret = 0;
 	status = fsi_reg_read(fsi, DOFF_ST);
-	if (status & ERR_OVER) {
+	if (!startup) {
 		struct snd_soc_dai *dai = fsi_get_dai(substream);
-		dev_err(dai->dev, "over run error\n");
-		fsi_reg_write(fsi, DOFF_ST, status & ~ST_ERR);
-		ret = -EIO;
+
+		if (status & ERR_OVER)
+			dev_err(dai->dev, "over run\n");
+		if (status & ERR_UNDER)
+			dev_err(dai->dev, "under run\n");
 	}
+	fsi_reg_write(fsi, DOFF_ST, 0);
 
 	fsi_irq_enable(fsi, 1);
 
 	if (over_period)
 		snd_pcm_period_elapsed(substream);
 
-	return ret;
+	return 0;
 }
 
-static int fsi_data_pop(struct fsi_priv *fsi)
+static int fsi_data_pop(struct fsi_priv *fsi, int startup)
 {
 	struct snd_pcm_runtime *runtime;
 	struct snd_pcm_substream *substream = NULL;
@@ -479,7 +481,7 @@
 	int fifo_fill;
 	int width;
 	u8 *start;
-	int i, ret, over_period;
+	int i, over_period;
 
 	if (!fsi			||
 	    !fsi->substream		||
@@ -534,21 +536,23 @@
 
 	fsi->byte_offset += fifo_fill * width;
 
-	ret = 0;
 	status = fsi_reg_read(fsi, DIFF_ST);
-	if (status & ERR_UNDER) {
+	if (!startup) {
 		struct snd_soc_dai *dai = fsi_get_dai(substream);
-		dev_err(dai->dev, "under run error\n");
-		fsi_reg_write(fsi, DIFF_ST, status & ~ST_ERR);
-		ret = -EIO;
+
+		if (status & ERR_OVER)
+			dev_err(dai->dev, "over run\n");
+		if (status & ERR_UNDER)
+			dev_err(dai->dev, "under run\n");
 	}
+	fsi_reg_write(fsi, DIFF_ST, 0);
 
 	fsi_irq_enable(fsi, 0);
 
 	if (over_period)
 		snd_pcm_period_elapsed(substream);
 
-	return ret;
+	return 0;
 }
 
 static irqreturn_t fsi_interrupt(int irq, void *data)
@@ -562,13 +566,13 @@
 	fsi_master_write(master, SOFT_RST, status | 0x00000010);
 
 	if (int_st & INT_A_OUT)
-		fsi_data_push(&master->fsia);
+		fsi_data_push(&master->fsia, 0);
 	if (int_st & INT_B_OUT)
-		fsi_data_push(&master->fsib);
+		fsi_data_push(&master->fsib, 0);
 	if (int_st & INT_A_IN)
-		fsi_data_pop(&master->fsia);
+		fsi_data_pop(&master->fsia, 0);
 	if (int_st & INT_B_IN)
-		fsi_data_pop(&master->fsib);
+		fsi_data_pop(&master->fsib, 0);
 
 	fsi_master_write(master, INT_ST, 0x0000000);
 
@@ -726,7 +730,7 @@
 		fsi_stream_push(fsi, substream,
 				frames_to_bytes(runtime, runtime->buffer_size),
 				frames_to_bytes(runtime, runtime->period_size));
-		ret = is_play ? fsi_data_push(fsi) : fsi_data_pop(fsi);
+		ret = is_play ? fsi_data_push(fsi, 1) : fsi_data_pop(fsi, 1);
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
 		fsi_irq_disable(fsi, is_play);