[PATCH v2] ASoC: atmel_ssc_dai: Don't unconditionally reset SSC on stream startup

[Peter Meerwald-Stadler <pmeerw@pmeerw.net>]

From: Christoph Huber <c.huber@bct-electronic.com>

commit cbaadf0f90d6 ("ASoC: atmel_ssc_dai: refactor the startup and
shutdown") refactored code such that the SSC is reset on every
startup; this breaks duplex audio (e.g. first start audio playback,
then start record, causing the playback to stop/hang)

Signed-off-by: Christoph Huber <c.huber@bct-electronic.com>
Signed-off-by: Peter Meerwald-Stadler <p.meerwald@bct-electronic.com>
Cc: Songjun Wu <songjun.wu@microchip.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
---
v2 fixes formatting issues and rephrases the comment

 sound/soc/atmel/atmel_ssc_dai.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sound/soc/atmel/atmel_ssc_dai.c b/sound/soc/atmel/atmel_ssc_dai.c
index 54c09ac..16e459a 100644
--- a/sound/soc/atmel/atmel_ssc_dai.c
+++ b/sound/soc/atmel/atmel_ssc_dai.c
@@ -299,8 +299,9 @@ static int atmel_ssc_startup(struct snd_pcm_substream *substream,
 	clk_enable(ssc_p->ssc->clk);
 	ssc_p->mck_rate = clk_get_rate(ssc_p->ssc->clk);
 
-	/* Reset the SSC to keep it at a clean status */
-	ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
+	/* Reset the SSC unless initialized to keep it in a clean state */
+	if (!ssc_p->initialized)
+		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
 
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 		dir = 0;
-- 
1.7.10.4