[tegra ALSA] Save/Restore I2S Registers on suspend/resume.

Added support to save and restore I2S registers on
suspend/resume.

For Bug: 774397

Change-Id: I2a0caf93f422811573ec2acd193de3804f8860a0
Reviewed-on: http://git-master/r/14454
Tested-by: Manjula Gupta <magupta@nvidia.com>
Reviewed-by: Vijay Mali <vmali@nvidia.com>
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>

2 files changed, 43 insertions, 18 deletions

diff --git a/sound/soc/tegra/tegra_i2s.c b/sound/soc/tegra/tegra_i2s.c
index 69e07b0c5181..1596c4f7be5e 100644
--- a/sound/soc/tegra/tegra_i2s.c
+++ b/sound/soc/tegra/tegra_i2s.c
@@ -20,6 +20,7 @@
 #include "tegra_soc.h"
 
 static void *das_base = IO_ADDRESS(TEGRA_APB_MISC_BASE);
+struct snd_soc_dai tegra_i2s_dai;
 
 static inline unsigned long das_readl(unsigned long offset)
 {
@@ -72,7 +73,7 @@ static int tegra_i2s_hw_params(struct snd_pcm_substream *substream,
 	}
 
 	i2s_set_channel_bit_count(I2S_IFC, val, clk_get_rate(prtd->i2s_clk));
-
+	tegra_i2s_dai.private_data = (void *)prtd;
 	return 0;
 
 err:
@@ -199,6 +200,26 @@ static int tegra_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
 	return ret;
 }
 
+#ifdef CONFIG_PM
+int tegra_i2s_suspend(struct snd_soc_dai *i2s_dai)
+{
+	struct tegra_runtime_data *prtd = (struct snd_pcm_runtime *)(tegra_i2s_dai.private_data);
+	i2s_get_all_regs(I2S_IFC, &prtd->i2s_regs);
+	return 0;
+}
+
+int tegra_i2s_resume(struct snd_soc_dai *i2s_dai)
+{
+	struct tegra_runtime_data *prtd = (struct snd_pcm_runtime *)(tegra_i2s_dai.private_data);
+	i2s_set_all_regs(I2S_IFC, &prtd->i2s_regs);
+	return 0;
+}
+
+#else
+#define tegra_i2s_suspend	NULL
+#define tegra_i2s_resume	NULL
+#endif
+
 static int tegra_i2s_startup(struct snd_pcm_substream *substream,
 				struct snd_soc_dai *dai)
 {
@@ -227,6 +248,23 @@ static int tegra_i2s_probe(struct platform_device *pdev,
 	return 0;
 }
 
+static int tegra_i2s_driver_probe(struct platform_device *dev)
+{
+	int ret;
+
+	tegra_i2s_dai.dev = &dev->dev;
+	tegra_i2s_dai.private_data = NULL;
+	ret = snd_soc_register_dai(&tegra_i2s_dai);
+	return ret;
+}
+
+
+static int __devexit tegra_i2s_driver_remove(struct platform_device *dev)
+{
+	snd_soc_unregister_dai(&tegra_i2s_dai);
+	return 0;
+}
+
 static struct snd_soc_dai_ops tegra_i2s_dai_ops = {
 	.startup	= tegra_i2s_startup,
 	.shutdown	= tegra_i2s_shutdown,
@@ -240,6 +278,8 @@ struct snd_soc_dai tegra_i2s_dai = {
 	.name = "tegra-i2s",
 	.id = 0,
 	.probe = tegra_i2s_probe,
+	.suspend = tegra_i2s_suspend,
+	.resume = tegra_i2s_resume,
 	.playback = {
 		.channels_min = 2,
 		.channels_max = 2,
@@ -256,23 +296,6 @@ struct snd_soc_dai tegra_i2s_dai = {
 };
 EXPORT_SYMBOL_GPL(tegra_i2s_dai);
 
-static int tegra_i2s_driver_probe(struct platform_device *dev)
-{
-	int ret;
-
-	tegra_i2s_dai.dev = &dev->dev;
-	tegra_i2s_dai.private_data = NULL;
-	ret = snd_soc_register_dai(&tegra_i2s_dai);
-	return ret;
-}
-
-
-static int __devexit tegra_i2s_driver_remove(struct platform_device *dev)
-{
-	snd_soc_unregister_dai(&tegra_i2s_dai);
-	return 0;
-}
-
 static struct platform_driver tegra_i2s_driver = {
 	.probe = tegra_i2s_driver_probe,
 	.remove = __devexit_p(tegra_i2s_driver_remove),
diff --git a/sound/soc/tegra/tegra_soc.h b/sound/soc/tegra/tegra_soc.h
index 5cb2a2ccf851..e570bcb39172 100644
--- a/sound/soc/tegra/tegra_soc.h
+++ b/sound/soc/tegra/tegra_soc.h
@@ -91,10 +91,12 @@ struct tegra_runtime_data {
 	struct tegra_dma_req dma_req1, dma_req2;
 	volatile int state;
 	int period_index;
+	int i2s_shutdown;
 	struct tegra_dma_channel *dma_chan;
 	struct clk *i2s_clk;
 	struct clk *dap_mclk;
 	struct clk *audio_sync_clk;
+	struct i2s_runtime_data i2s_regs;
 };
 
 #endif