Fix: try to stop aif clock in thread environment

ac101.c

@@ -644,7 +644,7 @@ static int ac101_sysclk_started(void) {
 
 static int ac101_aif1clk(struct snd_soc_codec* codec, int event, int quick) {
 	struct ac10x_priv *ac10x = snd_soc_codec_get_drvdata(codec);
-	int ret;
+	int ret = 0;
 
 	/* spin_lock move to machine trigger */
 
@@ -687,7 +687,7 @@ static int ac101_aif1clk(struct snd_soc_codec* codec, int event, int quick) {
 
 	AC101_DBG("event=%d pre_up/%d post_down/%d\n", event, SND_SOC_DAPM_PRE_PMU, SND_SOC_DAPM_POST_PMD);
 
-	return 0;
+	return ret;
 }
 
 /**
@@ -1240,15 +1240,17 @@ int ac101_audio_startup(struct snd_pcm_substream *substream,
 
 #if _MASTER_MULTI_CODEC == _MASTER_AC101
 static int ac101_set_clock(int y_start_n_stop) {
+	int r;
+
 	if (y_start_n_stop) {
 		/* enable global clock */
-		ac101_aif1clk(static_ac10x->codec, SND_SOC_DAPM_PRE_PMU, 1);
+		r = ac101_aif1clk(static_ac10x->codec, SND_SOC_DAPM_PRE_PMU, 1);
 	} else {
 		/* disable global clock */
 		static_ac10x->aif1_clken = 1;
-		ac101_aif1clk(static_ac10x->codec, SND_SOC_DAPM_POST_PMD, 0);
+		r = ac101_aif1clk(static_ac10x->codec, SND_SOC_DAPM_POST_PMD, 0);
 	}
-	return 0;
+	return r;
 }
 #endif
 

ac108.c

@@ -453,11 +453,13 @@ static int ac108_multi_write(u8 reg, u8 val, struct ac10x_priv *ac10x) {
 }
 
 static int ac108_multi_update_bits(u8 reg, u8 mask, u8 val, struct ac10x_priv *ac10x) {
+	int r = 0;
 	u8 i;
+
 	for (i = 0; i < ac10x->codec_cnt; i++) {
-		ac10x_update_bits(reg, mask, val, ac10x->i2cmap[i]);
+		r |= ac10x_update_bits(reg, mask, val, ac10x->i2cmap[i]);
 	}
-	return 0;
+	return r;
 }
 
 static unsigned int ac108_codec_read(struct snd_soc_codec *codec, unsigned int reg) {
@@ -986,46 +988,46 @@ static int ac108_set_fmt(struct snd_soc_dai *dai, unsigned int fmt) {
  * due to miss channels order in cpu_dai, we meed defer the clock starting.
  */
 static int ac108_set_clock(int y_start_n_stop) {
-	u8 r;
+	u8 reg;
+	int ret = 0;
 
 	dev_dbg(ac10x->codec->dev, "%s() L%d cmd:%d\n", __func__, __LINE__, y_start_n_stop);
 
 	/* spin_lock move to machine trigger */
 
-	if (y_start_n_stop)  {
+	if (y_start_n_stop && ac10x->sysclk_en == 0) {
-		if (ac10x->sysclk_en == 0) {
-
 		/* enable lrck clock */
-		ac10x_read(I2S_CTRL, &r, ac10x->i2cmap[_MASTER_INDEX]);
+		ac10x_read(I2S_CTRL, &reg, ac10x->i2cmap[_MASTER_INDEX]);
-		if (r & (0x01 << BCLK_IOEN)) {
+		if (reg & (0x01 << BCLK_IOEN)) {
-			ac10x_update_bits(I2S_CTRL, 0x03 << LRCK_IOEN, 0x03 << LRCK_IOEN, ac10x->i2cmap[_MASTER_INDEX]);
+			ret = ret || ac10x_update_bits(I2S_CTRL, 0x03 << LRCK_IOEN, 0x03 << LRCK_IOEN, ac10x->i2cmap[_MASTER_INDEX]);
 		}
 
 		/*0x10: PLL Common voltage enable, PLL enable */
-		ac108_multi_update_bits(PLL_CTRL1, 0x01 << PLL_EN | 0x01 << PLL_COM_EN,
+		ret = ret || ac108_multi_update_bits(PLL_CTRL1, 0x01 << PLL_EN | 0x01 << PLL_COM_EN,
 						   0x01 << PLL_EN | 0x01 << PLL_COM_EN, ac10x);
 		/* enable global clock */
-		ac108_multi_update_bits(I2S_CTRL, 0x1 << TXEN | 0x1 << GEN, 0x1 << TXEN | 0x1 << GEN, ac10x);
+		ret = ret || ac108_multi_update_bits(I2S_CTRL, 0x1 << TXEN | 0x1 << GEN, 0x1 << TXEN | 0x1 << GEN, ac10x);
 
 		ac10x->sysclk_en = 1UL;
-		}
+	} else if (!y_start_n_stop && ac10x->sysclk_en != 0) {
-	} else if (ac10x->sysclk_en != 0) {
 		/* disable global clock */
-		ac108_multi_update_bits(I2S_CTRL, 0x1 << TXEN | 0x1 << GEN, 0x0 << TXEN | 0x0 << GEN, ac10x);
+		ret = ret || ac108_multi_update_bits(I2S_CTRL, 0x1 << TXEN | 0x1 << GEN, 0x0 << TXEN | 0x0 << GEN, ac10x);
 
 		/*0x10: PLL Common voltage disable, PLL disable */
-		ac108_multi_update_bits(PLL_CTRL1, 0x01 << PLL_EN | 0x01 << PLL_COM_EN,
+		ret = ret || ac108_multi_update_bits(PLL_CTRL1, 0x01 << PLL_EN | 0x01 << PLL_COM_EN,
 						   0x00 << PLL_EN | 0x00 << PLL_COM_EN, ac10x);
 
 		/* disable lrck clock if it's enabled */
-		ac10x_read(I2S_CTRL, &r, ac10x->i2cmap[_MASTER_INDEX]);
+		ac10x_read(I2S_CTRL, &reg, ac10x->i2cmap[_MASTER_INDEX]);
-		if (r & (0x01 << LRCK_IOEN)) {
+		if (reg & (0x01 << LRCK_IOEN)) {
-			ac10x_update_bits(I2S_CTRL, 0x03 << LRCK_IOEN, 0x01 << BCLK_IOEN, ac10x->i2cmap[_MASTER_INDEX]);
+			ret = ret || ac10x_update_bits(I2S_CTRL, 0x03 << LRCK_IOEN, 0x01 << BCLK_IOEN, ac10x->i2cmap[_MASTER_INDEX]);
 		}
+		if (!ret) {
 			ac10x->sysclk_en = 0UL;
 		}
+	}
 
-	return 0;
+	return ret;
 }
 
 static int ac108_prepare(struct snd_pcm_substream *substream,

seeed-voicecard.c

@@ -48,6 +48,9 @@ struct seeed_card_data {
 	unsigned channels_capture_override;
 	struct snd_soc_dai_link *dai_link;
 	spinlock_t lock;
+	struct work_struct work_codec_clk;
+	#define TRY_STOP_MAX	3
+	int try_stop;
 };
 
 struct seeed_card_info {
@@ -161,6 +164,27 @@ int seeed_voice_card_register_set_clock(int stream, int (*set_clock)(int)) {
 }
 EXPORT_SYMBOL(seeed_voice_card_register_set_clock);
 
+/*
+ * work_cb_codec_clk: clear audio codec inner clock.
+ */
+static void work_cb_codec_clk(struct work_struct *work)
+{
+	struct seeed_card_data *priv = container_of(work, struct seeed_card_data, work_codec_clk);
+	int r = 0;
+
+	if (_set_clock[SNDRV_PCM_STREAM_CAPTURE]) {
+		r = r || _set_clock[SNDRV_PCM_STREAM_CAPTURE](0);
+	}
+	if (_set_clock[SNDRV_PCM_STREAM_PLAYBACK]) {
+		r = r || _set_clock[SNDRV_PCM_STREAM_PLAYBACK](0);
+	}
+
+	if (r && priv->try_stop++ < TRY_STOP_MAX) {
+		if (0 != schedule_work(&priv->work_codec_clk)) {}
+	}
+	return;
+}
+
 static int seeed_voice_card_trigger(struct snd_pcm_substream *substream, int cmd)
 {
 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
@@ -173,15 +197,16 @@ static int seeed_voice_card_trigger(struct snd_pcm_substream *substream, int cmd
 		__FUNCTION__, snd_pcm_stream_str(substream), cmd,
 		dai->playback_active, dai->capture_active);
 
-	/* I know it will degrades performance, but I have no choice */
-	spin_lock_irqsave(&priv->lock, flags);
-
 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_START:
 	case SNDRV_PCM_TRIGGER_RESUME:
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		if (cancel_work_sync(&priv->work_codec_clk) != 0) {}
+		/* I know it will degrades performance, but I have no choice */
+		spin_lock_irqsave(&priv->lock, flags);
 		if (_set_clock[SNDRV_PCM_STREAM_CAPTURE]) _set_clock[SNDRV_PCM_STREAM_CAPTURE](1);
 		if (_set_clock[SNDRV_PCM_STREAM_PLAYBACK]) _set_clock[SNDRV_PCM_STREAM_PLAYBACK](1);
+		spin_unlock_irqrestore(&priv->lock, flags);
 		break;
 
 	case SNDRV_PCM_TRIGGER_STOP:
@@ -191,15 +216,21 @@ static int seeed_voice_card_trigger(struct snd_pcm_substream *substream, int cmd
 		if (dai->capture_active && substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 			break;
 		}
+
+		/* interrupt environment */
+		if (in_irq() || in_nmi() || in_serving_softirq()) {
+			priv->try_stop = 0;
+			if (0 != schedule_work(&priv->work_codec_clk)) {
+			}
+		} else {
 			if (_set_clock[SNDRV_PCM_STREAM_CAPTURE]) _set_clock[SNDRV_PCM_STREAM_CAPTURE](0);
 			if (_set_clock[SNDRV_PCM_STREAM_PLAYBACK]) _set_clock[SNDRV_PCM_STREAM_PLAYBACK](0);
+		}
 		break;
 	default:
 		ret = -EINVAL;
 	}
 
-	spin_unlock_irqrestore(&priv->lock, flags);
-
 	return ret;
 }
 
@@ -558,6 +589,8 @@ static int seeed_voice_card_probe(struct platform_device *pdev)
 
 	spin_lock_init(&priv->lock);
 
+	INIT_WORK(&priv->work_codec_clk, work_cb_codec_clk);
+
 	ret = devm_snd_soc_register_card(&pdev->dev, &priv->snd_card);
 	if (ret >= 0)
 		return ret;
@@ -571,7 +604,10 @@ err:
 static int seeed_voice_card_remove(struct platform_device *pdev)
 {
 	struct snd_soc_card *card = platform_get_drvdata(pdev);
+	struct seeed_card_data *priv = snd_soc_card_get_drvdata(card);
 
+	if (cancel_work_sync(&priv->work_codec_clk) != 0) {
+	}
 	return asoc_simple_card_clean_reference(card);
 }