[alsa-devel] [PATCH] add power management S3 solution

[John Hsu]

This patch is to fix interrupt fails when resume back.
In solution, we add IRQ re-initiation,
and reconstruct suspend and resume with set_bias_level function.

Signed-off-by: John Hsu <KCHSU0 at nuvoton.com>
---
 sound/soc/codecs/nau8825.c | 42 ++++++++++++++++++++++++++++++++++++------
 1 file changed, 36 insertions(+), 6 deletions(-)

diff --git a/sound/soc/codecs/nau8825.c b/sound/soc/codecs/nau8825.c
index 504c969..2e2e11a 100644
--- a/sound/soc/codecs/nau8825.c
+++ b/sound/soc/codecs/nau8825.c
@@ -1092,6 +1092,36 @@ static int nau8825_set_sysclk(struct snd_soc_codec *codec, int clk_id,
 	return nau8825_configure_sysclk(nau8825, clk_id, freq);
 }
 
+static int nau8825_resume_setup(struct nau8825 *nau8825)
+{
+	struct regmap *regmap = nau8825->regmap;
+
+	/* IRQ Output Enable */
+	regmap_update_bits(regmap, NAU8825_REG_INTERRUPT_MASK,
+		NAU8825_IRQ_OUTPUT_EN, NAU8825_IRQ_OUTPUT_EN);
+
+	/* Enable internal VCO needed for interruptions */
+	nau8825_configure_sysclk(nau8825, NAU8825_CLK_INTERNAL, 0);
+
+	/* Enable DDACR needed for interrupts */
+	regmap_update_bits(regmap, NAU8825_REG_ENA_CTRL,
+		NAU8825_ENABLE_DACR, NAU8825_ENABLE_DACR);
+
+	/* Chip needs one FSCLK cycle in order to generate interrupts,
+	 * as we cannot guarantee one will be provided by the system. Turning
+	 * master mode on then off enables us to generate that FSCLK cycle
+	 * with a minimum of contention on the clock bus.
+	 */
+	regmap_update_bits(regmap, NAU8825_REG_I2S_PCM_CTRL2,
+		NAU8825_I2S_MS_MASK, NAU8825_I2S_MS_MASTER);
+	regmap_update_bits(regmap, NAU8825_REG_I2S_PCM_CTRL2,
+		NAU8825_I2S_MS_MASK, NAU8825_I2S_MS_SLAVE);
+
+	nau8825_restart_jack_detection(regmap);
+
+	return 0;
+}
+
 static int nau8825_set_bias_level(struct snd_soc_codec *codec,
 				   enum snd_soc_bias_level level)
 {
@@ -1121,6 +1151,8 @@ static int nau8825_set_bias_level(struct snd_soc_codec *codec,
 					"Failed to sync cache: %d\n", ret);
 				return ret;
 			}
+			if (nau8825->irq)
+				nau8825_resume_setup(nau8825);
 		}
 
 		break;
@@ -1330,24 +1362,22 @@ static int nau8825_i2c_remove(struct i2c_client *client)
 #ifdef CONFIG_PM_SLEEP
 static int nau8825_suspend(struct device *dev)
 {
-	struct i2c_client *client = to_i2c_client(dev);
 	struct nau8825 *nau8825 = dev_get_drvdata(dev);
+	struct snd_soc_codec *codec = snd_soc_dapm_to_codec(nau8825->dapm);
 
-	disable_irq(client->irq);
+	disable_irq(nau8825->irq);
+	snd_soc_codec_force_bias_level(codec, SND_SOC_BIAS_OFF);
 	regcache_cache_only(nau8825->regmap, true);
-	regcache_mark_dirty(nau8825->regmap);
 
 	return 0;
 }
 
 static int nau8825_resume(struct device *dev)
 {
-	struct i2c_client *client = to_i2c_client(dev);
 	struct nau8825 *nau8825 = dev_get_drvdata(dev);
 
 	regcache_cache_only(nau8825->regmap, false);
-	regcache_sync(nau8825->regmap);
-	enable_irq(client->irq);
+	enable_irq(nau8825->irq);
 
 	return 0;
 }
-- 
2.6.4