[PATCH] ASoC: fsl_esai: Add pm runtime function

["S.j. Wang" <shengjiu.wang@nxp.com>]

In imx8 when systerm enter suspend state, the power of subsystem will
be off, the clock enable state will be lost and register configuration
will be lost. So the driver need to enter runtime suspend state in
suspend.

With this implementation the suspend function almost same as runtime
suspend function, so remove the suspend function, just use
pm_runtime_force_suspend instead, and same for the resume function.

And also need to move clock enablement to runtime resume and clock
disablement to runtime suspend.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
---
 sound/soc/fsl/fsl_esai.c | 141 ++++++++++++++++++++++++++---------------------
 1 file changed, 77 insertions(+), 64 deletions(-)

diff --git a/sound/soc/fsl/fsl_esai.c b/sound/soc/fsl/fsl_esai.c
index bad0dfed6b68..b1e27db3752b 100644
--- a/sound/soc/fsl/fsl_esai.c
+++ b/sound/soc/fsl/fsl_esai.c
@@ -9,6 +9,7 @@
 #include <linux/module.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
 #include <sound/dmaengine_pcm.h>
 #include <sound/pcm_params.h>
 
@@ -466,30 +467,6 @@ static int fsl_esai_startup(struct snd_pcm_substream *substream,
 			    struct snd_soc_dai *dai)
 {
 	struct fsl_esai *esai_priv = snd_soc_dai_get_drvdata(dai);
-	int ret;
-
-	/*
-	 * Some platforms might use the same bit to gate all three or two of
-	 * clocks, so keep all clocks open/close at the same time for safety
-	 */
-	ret = clk_prepare_enable(esai_priv->coreclk);
-	if (ret)
-		return ret;
-	if (!IS_ERR(esai_priv->spbaclk)) {
-		ret = clk_prepare_enable(esai_priv->spbaclk);
-		if (ret)
-			goto err_spbaclk;
-	}
-	if (!IS_ERR(esai_priv->extalclk)) {
-		ret = clk_prepare_enable(esai_priv->extalclk);
-		if (ret)
-			goto err_extalck;
-	}
-	if (!IS_ERR(esai_priv->fsysclk)) {
-		ret = clk_prepare_enable(esai_priv->fsysclk);
-		if (ret)
-			goto err_fsysclk;
-	}
 
 	if (!dai->active) {
 		/* Set synchronous mode */
@@ -506,16 +483,6 @@ static int fsl_esai_startup(struct snd_pcm_substream *substream,
 
 	return 0;
 
-err_fsysclk:
-	if (!IS_ERR(esai_priv->extalclk))
-		clk_disable_unprepare(esai_priv->extalclk);
-err_extalck:
-	if (!IS_ERR(esai_priv->spbaclk))
-		clk_disable_unprepare(esai_priv->spbaclk);
-err_spbaclk:
-	clk_disable_unprepare(esai_priv->coreclk);
-
-	return ret;
 }
 
 static int fsl_esai_hw_params(struct snd_pcm_substream *substream,
@@ -576,20 +543,6 @@ static int fsl_esai_hw_params(struct snd_pcm_substream *substream,
 	return 0;
 }
 
-static void fsl_esai_shutdown(struct snd_pcm_substream *substream,
-			      struct snd_soc_dai *dai)
-{
-	struct fsl_esai *esai_priv = snd_soc_dai_get_drvdata(dai);
-
-	if (!IS_ERR(esai_priv->fsysclk))
-		clk_disable_unprepare(esai_priv->fsysclk);
-	if (!IS_ERR(esai_priv->extalclk))
-		clk_disable_unprepare(esai_priv->extalclk);
-	if (!IS_ERR(esai_priv->spbaclk))
-		clk_disable_unprepare(esai_priv->spbaclk);
-	clk_disable_unprepare(esai_priv->coreclk);
-}
-
 static int fsl_esai_trigger(struct snd_pcm_substream *substream, int cmd,
 			    struct snd_soc_dai *dai)
 {
@@ -658,7 +611,6 @@ static int fsl_esai_trigger(struct snd_pcm_substream *substream, int cmd,
 
 static const struct snd_soc_dai_ops fsl_esai_dai_ops = {
 	.startup = fsl_esai_startup,
-	.shutdown = fsl_esai_shutdown,
 	.trigger = fsl_esai_trigger,
 	.hw_params = fsl_esai_hw_params,
 	.set_sysclk = fsl_esai_set_dai_sysclk,
@@ -947,6 +899,10 @@ static int fsl_esai_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	pm_runtime_enable(&pdev->dev);
+
+	regcache_cache_only(esai_priv->regmap, true);
+
 	ret = imx_pcm_dma_init(pdev, IMX_ESAI_DMABUF_SIZE);
 	if (ret)
 		dev_err(&pdev->dev, "failed to init imx pcm dma: %d\n", ret);
@@ -954,6 +910,13 @@ static int fsl_esai_probe(struct platform_device *pdev)
 	return ret;
 }
 
+static int fsl_esai_remove(struct platform_device *pdev)
+{
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
 static const struct of_device_id fsl_esai_dt_ids[] = {
 	{ .compatible = "fsl,imx35-esai", },
 	{ .compatible = "fsl,vf610-esai", },
@@ -961,23 +924,37 @@ static int fsl_esai_probe(struct platform_device *pdev)
 };
 MODULE_DEVICE_TABLE(of, fsl_esai_dt_ids);
 
-#ifdef CONFIG_PM_SLEEP
-static int fsl_esai_suspend(struct device *dev)
-{
-	struct fsl_esai *esai = dev_get_drvdata(dev);
-
-	regcache_cache_only(esai->regmap, true);
-	regcache_mark_dirty(esai->regmap);
-
-	return 0;
-}
-
-static int fsl_esai_resume(struct device *dev)
+#ifdef CONFIG_PM
+static int fsl_esai_runtime_resume(struct device *dev)
 {
 	struct fsl_esai *esai = dev_get_drvdata(dev);
 	int ret;
 
+	/*
+	 * Some platforms might use the same bit to gate all three or two of
+	 * clocks, so keep all clocks open/close at the same time for safety
+	 */
+	ret = clk_prepare_enable(esai->coreclk);
+	if (ret)
+		return ret;
+	if (!IS_ERR(esai->spbaclk)) {
+		ret = clk_prepare_enable(esai->spbaclk);
+		if (ret)
+			goto err_spbaclk;
+	}
+	if (!IS_ERR(esai->extalclk)) {
+		ret = clk_prepare_enable(esai->extalclk);
+		if (ret)
+			goto err_extalclk;
+	}
+	if (!IS_ERR(esai->fsysclk)) {
+		ret = clk_prepare_enable(esai->fsysclk);
+		if (ret)
+			goto err_fsysclk;
+	}
+
 	regcache_cache_only(esai->regmap, false);
+	regcache_mark_dirty(esai->regmap);
 
 	/* FIFO reset for safety */
 	regmap_update_bits(esai->regmap, REG_ESAI_TFCR,
@@ -987,22 +964,58 @@ static int fsl_esai_resume(struct device *dev)
 
 	ret = regcache_sync(esai->regmap);
 	if (ret)
-		return ret;
+		goto err_regcache_sync;
 
 	/* FIFO reset done */
 	regmap_update_bits(esai->regmap, REG_ESAI_TFCR, ESAI_xFCR_xFR, 0);
 	regmap_update_bits(esai->regmap, REG_ESAI_RFCR, ESAI_xFCR_xFR, 0);
 
 	return 0;
+
+err_regcache_sync:
+	if (!IS_ERR(esai->fsysclk))
+		clk_disable_unprepare(esai->fsysclk);
+err_fsysclk:
+	if (!IS_ERR(esai->extalclk))
+		clk_disable_unprepare(esai->extalclk);
+err_extalclk:
+	if (!IS_ERR(esai->spbaclk))
+		clk_disable_unprepare(esai->spbaclk);
+err_spbaclk:
+	clk_disable_unprepare(esai->coreclk);
+
+	return ret;
+}
+
+static int fsl_esai_runtime_suspend(struct device *dev)
+{
+	struct fsl_esai *esai = dev_get_drvdata(dev);
+
+	regcache_cache_only(esai->regmap, true);
+
+	if (!IS_ERR(esai->fsysclk))
+		clk_disable_unprepare(esai->fsysclk);
+	if (!IS_ERR(esai->extalclk))
+		clk_disable_unprepare(esai->extalclk);
+	if (!IS_ERR(esai->spbaclk))
+		clk_disable_unprepare(esai->spbaclk);
+	clk_disable_unprepare(esai->coreclk);
+
+	return 0;
 }
-#endif /* CONFIG_PM_SLEEP */
+#endif /* CONFIG_PM */
 
 static const struct dev_pm_ops fsl_esai_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(fsl_esai_suspend, fsl_esai_resume)
+	SET_RUNTIME_PM_OPS(fsl_esai_runtime_suspend,
+			   fsl_esai_runtime_resume,
+			   NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
 };
 
 static struct platform_driver fsl_esai_driver = {
 	.probe = fsl_esai_probe,
+	.remove = fsl_esai_remove,
 	.driver = {
 		.name = "fsl-esai-dai",
 		.pm = &fsl_esai_pm_ops,
-- 
1.9.1