[alsa-devel] [PATCH v2] ASoC: davinci-mcasp: Allow complete shutdown of McASP when not in use

[Peter Ujfalusi]

Rearrange the pm_runtime_get/put_sync calls so the IP will be turned off
when it is not in use.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi at ti.com>
---
Hi,

Changs since v1:
- use om_runtime_put instead of the _sync variant whenever it is feasible
- Use pm runtime API to get information about the power state of McASP at supend
  and use the saved information on resume to do the right thing.

Regards,
Peter

 sound/soc/davinci/davinci-mcasp.c | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
index 0c882995a357..33cea0728cd2 100644
--- a/sound/soc/davinci/davinci-mcasp.c
+++ b/sound/soc/davinci/davinci-mcasp.c
@@ -62,6 +62,7 @@ struct davinci_mcasp_context {
 	u32	config_regs[ARRAY_SIZE(context_regs)];
 	u32	afifo_regs[2]; /* for read/write fifo control registers */
 	u32	*xrsr_regs; /* for serializer configuration */
+	bool	pm_state;
 };
 
 struct davinci_mcasp {
@@ -519,7 +520,7 @@ static int davinci_mcasp_set_dai_fmt(struct snd_soc_dai *cpu_dai,
 		mcasp_set_bits(mcasp, DAVINCI_MCASP_RXFMCTL_REG, FSRPOL);
 	}
 out:
-	pm_runtime_put_sync(mcasp->dev);
+	pm_runtime_put(mcasp->dev);
 	return ret;
 }
 
@@ -528,6 +529,7 @@ static int __davinci_mcasp_set_clkdiv(struct snd_soc_dai *dai, int div_id,
 {
 	struct davinci_mcasp *mcasp = snd_soc_dai_get_drvdata(dai);
 
+	pm_runtime_get_sync(mcasp->dev);
 	switch (div_id) {
 	case 0:		/* MCLK divider */
 		mcasp_mod_bits(mcasp, DAVINCI_MCASP_AHCLKXCTL_REG,
@@ -553,6 +555,7 @@ static int __davinci_mcasp_set_clkdiv(struct snd_soc_dai *dai, int div_id,
 		return -EINVAL;
 	}
 
+	pm_runtime_put(mcasp->dev);
 	return 0;
 }
 
@@ -567,6 +570,7 @@ static int davinci_mcasp_set_sysclk(struct snd_soc_dai *dai, int clk_id,
 {
 	struct davinci_mcasp *mcasp = snd_soc_dai_get_drvdata(dai);
 
+	pm_runtime_get_sync(mcasp->dev);
 	if (dir == SND_SOC_CLOCK_OUT) {
 		mcasp_set_bits(mcasp, DAVINCI_MCASP_AHCLKXCTL_REG, AHCLKXE);
 		mcasp_set_bits(mcasp, DAVINCI_MCASP_AHCLKRCTL_REG, AHCLKRE);
@@ -579,6 +583,7 @@ static int davinci_mcasp_set_sysclk(struct snd_soc_dai *dai, int clk_id,
 
 	mcasp->sysclk_freq = freq;
 
+	pm_runtime_put(mcasp->dev);
 	return 0;
 }
 
@@ -1053,6 +1058,10 @@ static int davinci_mcasp_suspend(struct snd_soc_dai *dai)
 	u32 reg;
 	int i;
 
+	context->pm_state = pm_runtime_enabled(mcasp->dev)
+	if (!context->pm_state)
+		pm_runtime_get_sync(mcasp->dev);
+
 	for (i = 0; i < ARRAY_SIZE(context_regs); i++)
 		context->config_regs[i] = mcasp_get_reg(mcasp, context_regs[i]);
 
@@ -1069,6 +1078,8 @@ static int davinci_mcasp_suspend(struct snd_soc_dai *dai)
 		context->xrsr_regs[i] = mcasp_get_reg(mcasp,
 						DAVINCI_MCASP_XRSRCTL_REG(i));
 
+	pm_runtime_put_sync(mcasp->dev);
+
 	return 0;
 }
 
@@ -1079,6 +1090,8 @@ static int davinci_mcasp_resume(struct snd_soc_dai *dai)
 	u32 reg;
 	int i;
 
+	pm_runtime_get_sync(mcasp->dev);
+
 	for (i = 0; i < ARRAY_SIZE(context_regs); i++)
 		mcasp_set_reg(mcasp, context_regs[i], context->config_regs[i]);
 
@@ -1095,6 +1108,9 @@ static int davinci_mcasp_resume(struct snd_soc_dai *dai)
 		mcasp_set_reg(mcasp, DAVINCI_MCASP_XRSRCTL_REG(i),
 			      context->xrsr_regs[i]);
 
+	if (!context->pm_state)
+		pm_runtime_put_sync(mcasp->dev);
+
 	return 0;
 }
 #else
@@ -1398,13 +1414,6 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
 
 	pm_runtime_enable(&pdev->dev);
 
-	ret = pm_runtime_get_sync(&pdev->dev);
-	if (IS_ERR_VALUE(ret)) {
-		dev_err(&pdev->dev, "pm_runtime_get_sync() failed\n");
-		pm_runtime_disable(&pdev->dev);
-		return ret;
-	}
-
 	mcasp->base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem));
 	if (!mcasp->base) {
 		dev_err(&pdev->dev, "ioremap failed\n");
@@ -1584,14 +1593,12 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
 	return 0;
 
 err:
-	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	return ret;
 }
 
 static int davinci_mcasp_remove(struct platform_device *pdev)
 {
-	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
 	return 0;
-- 
2.3.0