Asoc: Samsung: Add support for I2S runtime S2R

This patch adds runtime suspend to resume support for I2S

BUG=chrome-os-partner:12579
TEST=Tested by playing audio before suspend and after resume
using aplay command. I2S get suspended after probe and resume
upon audio playback.

Change-Id: Icd507188bbe2bb39e3bb9240ef6793b4ba937901
Signed-off-by: Padmavathi Venna <padma.v@samsung.com>
Reviewed-on: https://gerrit.chromium.org/gerrit/29991
Reviewed-by: Jon Kliegman <kliegs@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>
Commit-Ready: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>

diff --git a/sound/soc/samsung/i2s.c b/sound/soc/samsung/i2s.c
index 15392f7..4220efb 100644 (file)
--- a/sound/soc/samsung/i2s.c
+++ b/sound/soc/samsung/i2s.c
@@ -631,6 +631,15 @@ static int i2s_hw_params(struct snd_pcm_substream *substream,
        return 0;
 }
 
+static void pm_runtime_ctl(struct i2s_dai *i2s, bool enabled)
+{
+       struct platform_device *pdev = NULL;
+
+       pdev = is_secondary(i2s) ? i2s->pri_dai->pdev : i2s->pdev;
+       enabled ? pm_runtime_get_sync(&pdev->dev)
+               : pm_runtime_put_sync(&pdev->dev);
+}
+
 /* We set constraints on the substream acc to the version of I2S */
 static int i2s_startup(struct snd_pcm_substream *substream,
          struct snd_soc_dai *dai)
@@ -639,6 +648,8 @@ static int i2s_startup(struct snd_pcm_substream *substream,
        struct i2s_dai *other = i2s->pri_dai ? : i2s->sec_dai;
        unsigned long flags;
 
+       pm_runtime_ctl(i2s, true);
+
        spin_lock_irqsave(&lock, flags);
 
        i2s->mode |= DAI_OPENED;
@@ -681,6 +692,8 @@ static void i2s_shutdown(struct snd_pcm_substream *substream,
        if (!is_opened(other))
                i2s_set_sysclk(dai, SAMSUNG_I2S_CDCLK,
                                0, SND_SOC_CLOCK_IN);
+
+        pm_runtime_ctl(i2s, false);
 }
 
 static int config_setup(struct i2s_dai *i2s)
@@ -862,6 +875,26 @@ static int i2s_resume(struct snd_soc_dai *dai)
 #define i2s_resume  NULL
 #endif
 
+#ifdef CONFIG_PM_RUNTIME
+static int i2s_runtime_suspend(struct device *dev)
+{
+       struct i2s_dai *i2s = dev_get_drvdata(dev);
+
+       clk_disable(i2s->clk);
+
+       return 0;
+}
+
+static int i2s_runtime_resume(struct device *dev)
+{
+       struct i2s_dai *i2s = dev_get_drvdata(dev);
+
+       clk_enable(i2s->clk);
+
+       return 0;
+}
+#endif /* CONFIG_PM_RUNTIME */
+
 static int samsung_i2s_dai_probe(struct snd_soc_dai *dai)
 {
        struct i2s_dai *i2s = to_info(dai);
@@ -911,6 +944,7 @@ probe_exit:
                i2s_set_sysclk(dai, SAMSUNG_I2S_CDCLK,
                                0, SND_SOC_CLOCK_IN);
 
+       clk_disable(i2s->clk);
        return 0;
 }
 
@@ -1190,12 +1224,18 @@ static const struct of_device_id exynos_i2s_match[] = {
 MODULE_DEVICE_TABLE(of, exynos_i2s_match);
 #endif
 
+static const struct dev_pm_ops samsung_i2s_pm = {
+       SET_RUNTIME_PM_OPS(i2s_runtime_suspend,
+                               i2s_runtime_resume, NULL)
+};
+
 static struct platform_driver samsung_i2s_driver = {
        .probe  = samsung_i2s_probe,
        .remove = __devexit_p(samsung_i2s_remove),
        .driver = {
                .name = "samsung-i2s",
                .owner = THIS_MODULE,
+               .pm = &samsung_i2s_pm,
                .of_match_table = of_match_ptr(exynos_i2s_match),
        },
 };