[PATCH 4.4 136/312] ASoC: fsl_ssi: mark SACNT register volatile

[Greg Kroah-Hartman]

From: Maciej S. Szmigiero <mail@xxxxxxxxxxxxxxxxxxxxx>

commit 3f1c241f0f5f90046258e6b8d4aeb6463ffdc08e upstream.

SACNT register should be marked volatile since
its WR and RD bits are cleared by SSI after
completing the relevant operation.
This unbreaks AC'97 register access.

Fixes: 05cf237972fe ("ASoC: fsl_ssi: Add driver suspend and resume to support MEGA Fast")

Signed-off-by: Maciej S. Szmigiero <mail@xxxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Fabio Estevam <fabio.estevam@xxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 sound/soc/fsl/fsl_ssi.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/sound/soc/fsl/fsl_ssi.c
+++ b/sound/soc/fsl/fsl_ssi.c
@@ -146,6 +146,7 @@ static bool fsl_ssi_volatile_reg(struct
 	case CCSR_SSI_SRX1:
 	case CCSR_SSI_SISR:
 	case CCSR_SSI_SFCSR:
+	case CCSR_SSI_SACNT:
 	case CCSR_SSI_SACADD:
 	case CCSR_SSI_SACDAT:
 	case CCSR_SSI_SATAG:
@@ -239,8 +240,9 @@ struct fsl_ssi_private {
 	unsigned int baudclk_streams;
 	unsigned int bitclk_freq;
 
-	/*regcache for SFCSR*/
+	/* regcache for volatile regs */
 	u32 regcache_sfcsr;
+	u32 regcache_sacnt;
 
 	/* DMA params */
 	struct snd_dmaengine_dai_dma_data dma_params_tx;
@@ -1597,6 +1599,8 @@ static int fsl_ssi_suspend(struct device
 
 	regmap_read(regs, CCSR_SSI_SFCSR,
 			&ssi_private->regcache_sfcsr);
+	regmap_read(regs, CCSR_SSI_SACNT,
+			&ssi_private->regcache_sacnt);
 
 	regcache_cache_only(regs, true);
 	regcache_mark_dirty(regs);
@@ -1615,6 +1619,8 @@ static int fsl_ssi_resume(struct device
 			CCSR_SSI_SFCSR_RFWM1_MASK | CCSR_SSI_SFCSR_TFWM1_MASK |
 			CCSR_SSI_SFCSR_RFWM0_MASK | CCSR_SSI_SFCSR_TFWM0_MASK,
 			ssi_private->regcache_sfcsr);
+	regmap_write(regs, CCSR_SSI_SACNT,
+			ssi_private->regcache_sacnt);
 
 	return regcache_sync(regs);
 }