ASoC: tegra: add runtime PM support

To the Tegra I2S and SPDIF drivers

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 47 insertions, 7 deletions

diff --git a/sound/soc/tegra/tegra20_i2s.c b/sound/soc/tegra/tegra20_i2s.c
index 9427f36e6a25..b598ebdefdee 100644
--- a/sound/soc/tegra/tegra20_i2s.c
+++ b/sound/soc/tegra/tegra20_i2s.c
@@ -35,6 +35,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <sound/core.h>
@@ -56,6 +57,29 @@ static inline u32 tegra20_i2s_read(struct tegra20_i2s *i2s, u32 reg)
         return __raw_readl(i2s->regs + reg);
 }
 
+static int tegra20_i2s_runtime_suspend(struct device *dev)
+{
+        struct tegra20_i2s *i2s = dev_get_drvdata(dev);
+
+        clk_disable(i2s->clk_i2s);
+
+        return 0;
+}
+
+static int tegra20_i2s_runtime_resume(struct device *dev)
+{
+        struct tegra20_i2s *i2s = dev_get_drvdata(dev);
+        int ret;
+
+        ret = clk_enable(i2s->clk_i2s);
+        if (ret) {
+                dev_err(dev, "clk_enable failed: %d\n", ret);
+                return ret;
+        }
+
+        return 0;
+}
+
 #ifdef CONFIG_DEBUG_FS
 static int tegra20_i2s_show(struct seq_file *s, void *unused)
 {
@@ -219,16 +243,12 @@ static int tegra20_i2s_hw_params(struct snd_pcm_substream *substream,
         if (i2sclock % (2 * srate))
                 reg |= TEGRA20_I2S_TIMING_NON_SYM_ENABLE;
 
-        clk_enable(i2s->clk_i2s);
-
         tegra20_i2s_write(i2s, TEGRA20_I2S_TIMING, reg);
 
         tegra20_i2s_write(i2s, TEGRA20_I2S_FIFO_SCR,
                 TEGRA20_I2S_FIFO_SCR_FIFO2_ATN_LVL_FOUR_SLOTS |
                 TEGRA20_I2S_FIFO_SCR_FIFO1_ATN_LVL_FOUR_SLOTS);
 
-        clk_disable(i2s->clk_i2s);
-
         return 0;
 }
 
@@ -265,7 +285,6 @@ static int tegra20_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
         case SNDRV_PCM_TRIGGER_START:
         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
         case SNDRV_PCM_TRIGGER_RESUME:
-                clk_enable(i2s->clk_i2s);
                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                         tegra20_i2s_start_playback(i2s);
                 else
@@ -278,7 +297,6 @@ static int tegra20_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
                         tegra20_i2s_stop_playback(i2s);
                 else
                         tegra20_i2s_stop_capture(i2s);
-                clk_disable(i2s->clk_i2s);
                 break;
         default:
                 return -EINVAL;
@@ -395,11 +413,18 @@ static __devinit int tegra20_i2s_platform_probe(struct platform_device *pdev)
 
         i2s->reg_ctrl = TEGRA20_I2S_CTRL_FIFO_FORMAT_PACKED;
 
+        pm_runtime_enable(&pdev->dev);
+        if (!pm_runtime_enabled(&pdev->dev)) {
+                ret = tegra20_i2s_runtime_resume(&pdev->dev);
+                if (ret)
+                        goto err_pm_disable;
+        }
+
         ret = snd_soc_register_dai(&pdev->dev, &i2s->dai);
         if (ret) {
                 dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
                 ret = -ENOMEM;
-                goto err_clk_put;
+                goto err_suspend;
         }
 
         ret = tegra_pcm_platform_register(&pdev->dev);
@@ -414,6 +439,11 @@ static __devinit int tegra20_i2s_platform_probe(struct platform_device *pdev)
 
 err_unregister_dai:
         snd_soc_unregister_dai(&pdev->dev);
+err_suspend:
+        if (!pm_runtime_status_suspended(&pdev->dev))
+                tegra20_i2s_runtime_suspend(&pdev->dev);
+err_pm_disable:
+        pm_runtime_disable(&pdev->dev);
 err_clk_put:
         clk_put(i2s->clk_i2s);
 err:
@@ -424,6 +454,10 @@ static int __devexit tegra20_i2s_platform_remove(struct platform_device *pdev)
 {
         struct tegra20_i2s *i2s = dev_get_drvdata(&pdev->dev);
 
+        pm_runtime_disable(&pdev->dev);
+        if (!pm_runtime_status_suspended(&pdev->dev))
+                tegra20_i2s_runtime_suspend(&pdev->dev);
+
         tegra_pcm_platform_unregister(&pdev->dev);
         snd_soc_unregister_dai(&pdev->dev);
 
@@ -439,11 +473,17 @@ static const struct of_device_id tegra20_i2s_of_match[] __devinitconst = {
         {},
 };
 
+static const struct dev_pm_ops tegra20_i2s_pm_ops __devinitconst = {
+        SET_RUNTIME_PM_OPS(tegra20_i2s_runtime_suspend,
+                           tegra20_i2s_runtime_resume, NULL)
+};
+
 static struct platform_driver tegra20_i2s_driver = {
         .driver = {
                 .name = DRV_NAME,
                 .owner = THIS_MODULE,
                 .of_match_table = tegra20_i2s_of_match,
+                .pm = &tegra20_i2s_pm_ops,
         },
         .probe = tegra20_i2s_platform_probe,
         .remove = __devexit_p(tegra20_i2s_platform_remove),