2 files changed, 32 insertions, 0 deletions

diff --git a/sound/soc/tegra/tegra20_i2s.c b/sound/soc/tegra/tegra20_i2s.c
index d7a3d046c8f8..c0af5352b483 100644
--- a/sound/soc/tegra/tegra20_i2s.c
+++ b/sound/soc/tegra/tegra20_i2s.c
@@ -22,6 +22,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
+#include <linux/reset.h>
 #include <linux/slab.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
@@ -37,6 +38,8 @@ static int tegra20_i2s_runtime_suspend(struct device *dev)
 {
 	struct tegra20_i2s *i2s = dev_get_drvdata(dev);
 
+	regcache_cache_only(i2s->regmap, true);
+
 	clk_disable_unprepare(i2s->clk_i2s);
 
 	return 0;
@@ -47,13 +50,35 @@ static int tegra20_i2s_runtime_resume(struct device *dev)
 	struct tegra20_i2s *i2s = dev_get_drvdata(dev);
 	int ret;
 
+	ret = reset_control_assert(i2s->reset);
+	if (ret)
+		return ret;
+
 	ret = clk_prepare_enable(i2s->clk_i2s);
 	if (ret) {
 		dev_err(dev, "clk_enable failed: %d\n", ret);
 		return ret;
 	}
 
+	usleep_range(10, 100);
+
+	ret = reset_control_deassert(i2s->reset);
+	if (ret)
+		goto disable_clocks;
+
+	regcache_cache_only(i2s->regmap, false);
+	regcache_mark_dirty(i2s->regmap);
+
+	ret = regcache_sync(i2s->regmap);
+	if (ret)
+		goto disable_clocks;
+
 	return 0;
+
+disable_clocks:
+	clk_disable_unprepare(i2s->clk_i2s);
+
+	return ret;
 }
 
 static int tegra20_i2s_set_fmt(struct snd_soc_dai *dai,
@@ -339,6 +364,12 @@ static int tegra20_i2s_platform_probe(struct platform_device *pdev)
 	i2s->dai = tegra20_i2s_dai_template;
 	i2s->dai.name = dev_name(&pdev->dev);
 
+	i2s->reset = devm_reset_control_get_exclusive(&pdev->dev, "i2s");
+	if (IS_ERR(i2s->reset)) {
+		dev_err(&pdev->dev, "Can't retrieve i2s reset\n");
+		return PTR_ERR(i2s->reset);
+	}
+
 	i2s->clk_i2s = clk_get(&pdev->dev, NULL);
 	if (IS_ERR(i2s->clk_i2s)) {
 		dev_err(&pdev->dev, "Can't retrieve i2s clock\n");
diff --git a/sound/soc/tegra/tegra20_i2s.h b/sound/soc/tegra/tegra20_i2s.h
index 628d3ca09f42..8233e5fa2eff 100644
--- a/sound/soc/tegra/tegra20_i2s.h
+++ b/sound/soc/tegra/tegra20_i2s.h
@@ -144,6 +144,7 @@ struct tegra20_i2s {
 	struct snd_dmaengine_dai_dma_data capture_dma_data;
 	struct snd_dmaengine_dai_dma_data playback_dma_data;
 	struct regmap *regmap;
+	struct reset_control *reset;
 };
 
 #endif