ASoC: pxa2xx-i2s: Proper initialization

Reset FIFO logic and registers, and make sure REC and RPL functions along
with FIFO service are disabled at probe.
Signed-off-by: NKarl Beldan <karl.beldan@mobile-devices.fr>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/pxa/pxa2xx-i2s.c

@@ -347,6 +347,19 @@ static int pxa2xx_i2s_probe(struct platform_device *dev)
 	if (ret != 0)
 		clk_put(clk_i2s);
 
+	/*
+	 * PXA Developer's Manual:
+	 * If SACR0[ENB] is toggled in the middle of a normal operation,
+	 * the SACR0[RST] bit must also be set and cleared to reset all
+	 * I2S controller registers.
+	 */
+	SACR0 = SACR0_RST;
+	SACR0 = 0;
+	/* Make sure RPL and REC are disabled */
+	SACR1 = SACR1_DRPL | SACR1_DREC;
+	/* Along with FIFO servicing */
+	SAIMR &= ~(SAIMR_RFS | SAIMR_TFS);
+
 	return ret;
 }