ASoC: samsung: i2s: Move saving and restoring regs to runtime pm operations

This patch moves saving and restoring I2S registers to runtime PM
operations, what prepares the driver to operate with audio power domain.
When support for audio power domain is enabled and the domain is being
turned off, the I2S module will loose its context (registers), so runtime
callbacks have to handle it. System sleep suspend/resume operation are
implemented on top of runtime PM operations with generic
pm_runtime_force_suspend/resume helpers.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/samsung/i2s.c

@@ -983,24 +983,12 @@ i2s_delay(struct snd_pcm_substream *substream, struct snd_soc_dai *dai)
 #ifdef CONFIG_PM
 static int i2s_suspend(struct snd_soc_dai *dai)
 {
-	struct i2s_dai *i2s = to_info(dai);
-
-	i2s->suspend_i2smod = readl(i2s->addr + I2SMOD);
-	i2s->suspend_i2scon = readl(i2s->addr + I2SCON);
-	i2s->suspend_i2spsr = readl(i2s->addr + I2SPSR);
-
-	return 0;
+	return pm_runtime_force_suspend(dai->dev);
 }
 
 static int i2s_resume(struct snd_soc_dai *dai)
 {
-	struct i2s_dai *i2s = to_info(dai);
-
-	writel(i2s->suspend_i2scon, i2s->addr + I2SCON);
-	writel(i2s->suspend_i2smod, i2s->addr + I2SMOD);
-	writel(i2s->suspend_i2spsr, i2s->addr + I2SPSR);
-
-	return 0;
+	return pm_runtime_force_resume(dai->dev);
 }
 #else
 #define i2s_suspend NULL
@@ -1129,6 +1117,10 @@ static int i2s_runtime_suspend(struct device *dev)
 {
 	struct i2s_dai *i2s = dev_get_drvdata(dev);
 
+	i2s->suspend_i2smod = readl(i2s->addr + I2SMOD);
+	i2s->suspend_i2scon = readl(i2s->addr + I2SCON);
+	i2s->suspend_i2spsr = readl(i2s->addr + I2SPSR);
+
 	clk_disable_unprepare(i2s->clk);
 
 	return 0;
@@ -1140,6 +1132,10 @@ static int i2s_runtime_resume(struct device *dev)
 
 	clk_prepare_enable(i2s->clk);
 
+	writel(i2s->suspend_i2scon, i2s->addr + I2SCON);
+	writel(i2s->suspend_i2smod, i2s->addr + I2SMOD);
+	writel(i2s->suspend_i2spsr, i2s->addr + I2SPSR);
+
 	return 0;
 }
 #endif /* CONFIG_PM */
@@ -1510,6 +1506,8 @@ MODULE_DEVICE_TABLE(of, exynos_i2s_match);
 static const struct dev_pm_ops samsung_i2s_pm = {
 	SET_RUNTIME_PM_OPS(i2s_runtime_suspend,
 				i2s_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				     pm_runtime_force_resume)
 };
 
 static struct platform_driver samsung_i2s_driver = {