[alsa-devel] [PATCH] ASoC: nau8825: Modify power management and add interrupt wakeup

[John Hsu]

1. Enhance codec suspend and resume sequence
2. Add interrupt wakeup function

Signed-off-by: John Hsu <KCHSU0 at nuvoton.com>
---
 sound/soc/codecs/nau8825.c | 86 ++++++++++++++++++++++++++++++++++++++++++----
 sound/soc/codecs/nau8825.h |  2 ++
 2 files changed, 81 insertions(+), 7 deletions(-)

diff --git a/sound/soc/codecs/nau8825.c b/sound/soc/codecs/nau8825.c
index 504c969..9a02d05 100644
--- a/sound/soc/codecs/nau8825.c
+++ b/sound/soc/codecs/nau8825.c
@@ -543,6 +543,45 @@ int nau8825_enable_jack_detect(struct snd_soc_codec *codec,
 }
 EXPORT_SYMBOL_GPL(nau8825_enable_jack_detect);
 
+/**
+ * nau8825_init_wakeup - set wakeup capability for codec
+ *
+ * @codec:  codec device component
+ *
+ * After this function done, codec can support system wakeup by button.
+ */
+int nau8825_init_wakeup(struct snd_soc_codec *codec)
+{
+	struct nau8825 *nau8825 = snd_soc_codec_get_drvdata(codec);
+
+	device_init_wakeup(nau8825->dev, true);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nau8825_init_wakeup);
+
+/**
+ * nau8825_irq_wakeup - set interrupt can wakeup or not
+ *
+ * @codec:  codec device component
+ * @on:  switch interrupt wakeup on/off
+ *
+ * This function can enable or disable interrupt wakeup.
+ */
+int nau8825_irq_wakeup(struct snd_soc_codec *codec, int on)
+{
+	struct nau8825 *nau8825 = snd_soc_codec_get_drvdata(codec);
+
+	if (device_may_wakeup(nau8825->dev)) {
+		if (on)
+			enable_irq_wake(nau8825->irq);
+		else
+			disable_irq_wake(nau8825->irq);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nau8825_irq_wakeup);
 
 static bool nau8825_is_jack_inserted(struct regmap *regmap)
 {
@@ -676,7 +715,10 @@ static irqreturn_t nau8825_interrupt(int irq, void *data)
 	struct regmap *regmap = nau8825->regmap;
 	int active_irq, clear_irq = 0, event = 0, event_mask = 0;
 
-	regmap_read(regmap, NAU8825_REG_IRQ_STATUS, &active_irq);
+	if (regmap_read(regmap, NAU8825_REG_IRQ_STATUS, &active_irq)) {
+		dev_err(nau8825->dev, "failed to clear interrupt\n");
+		return IRQ_NONE;
+	}
 
 	if ((active_irq & NAU8825_JACK_EJECTION_IRQ_MASK) ==
 		NAU8825_JACK_EJECTION_DETECTED) {
@@ -1092,6 +1134,36 @@ 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 +1193,8 @@ 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 +1404,22 @@ 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;
 }
diff --git a/sound/soc/codecs/nau8825.h b/sound/soc/codecs/nau8825.h
index 8237693..00e7661 100644
--- a/sound/soc/codecs/nau8825.h
+++ b/sound/soc/codecs/nau8825.h
@@ -347,6 +347,8 @@ struct nau8825 {
 
 int nau8825_enable_jack_detect(struct snd_soc_codec *codec,
 				struct snd_soc_jack *jack);
+int nau8825_init_wakeup(struct snd_soc_codec *codec);
+int nau8825_irq_wakeup(struct snd_soc_codec *codec, int on);
 
 
 #endif  /* __NAU8825_H__ */
-- 
2.6.4