Subject: [PATCH AUTOSEL 4.19 089/128] ASoC: fsl_ssi: Fix clock control issue in master mode

From: Sasha Levin <[email-masked]>
Date: Sun, 22 Sep 2019 14:53:39 -0400

From: Shengjiu Wang <[email-masked]>

[ Upstream commit 696d05225cebffd172008d212657be90e823eac0 ]

The test case is
arecord -Dhw:0 -d 10 -f S16_LE -r 48000 -c 2 temp.wav &
aplay -Dhw:0 -d 30 -f S16_LE -r 48000 -c 2 test.wav

There will be error after end of arecord:
aplay: pcm_write:2051: write error: Input/output error

Capture and Playback work in parallel in master mode, one
substream stops, the other substream is impacted, the
reason is that clock is disabled wrongly.

The clock's reference count is not increased when second
substream starts, the hw_param() function returns in the
beginning because first substream is enabled, then in end
of first substream, the hw_free() disables the clock.

This patch is to move the clock enablement to the place
before checking of the device enablement in hw_param().

Signed-off-by: Shengjiu Wang <[email-masked]>
Link: https://lore.kernel.org/r/[email-masked]
Signed-off-by: Mark Brown <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 sound/soc/fsl/fsl_ssi.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c
index 0a648229e6430..bc1372c5f3243 100644
--- a/sound/soc/fsl/fsl_ssi.c
+++ b/sound/soc/fsl/fsl_ssi.c
@@ -799,15 +799,6 @@ static int fsl_ssi_hw_params(struct snd_pcm_substream *substream,
 	u32 wl = SSI_SxCCR_WL(sample_size);
 	int ret;
 
-	/*
-	 * SSI is properly configured if it is enabled and running in
-	 * the synchronous mode; Note that AC97 mode is an exception
-	 * that should set separate configurations for STCCR and SRCCR
-	 * despite running in the synchronous mode.
-	 */
-	if (ssi->streams && ssi->synchronous)
-		return 0;
-
 	if (fsl_ssi_is_i2s_master(ssi)) {
 		ret = fsl_ssi_set_bclk(substream, dai, hw_params);
 		if (ret)
@@ -823,6 +814,15 @@ static int fsl_ssi_hw_params(struct snd_pcm_substream *substream,
 		}
 	}
 
+	/*
+	 * SSI is properly configured if it is enabled and running in
+	 * the synchronous mode; Note that AC97 mode is an exception
+	 * that should set separate configurations for STCCR and SRCCR
+	 * despite running in the synchronous mode.
+	 */
+	if (ssi->streams && ssi->synchronous)
+		return 0;
+
 	if (!fsl_ssi_is_ac97(ssi)) {
 		/*
 		 * Keep the ssi->i2s_net intact while having a local variable
-- 
2.20.1