ASoC: wm8994: Defer declaration of open circuit microphones

Provide a bit of debounce to handle pathological cases with slow input
better by allowing the microphone detection to run for a bit longer.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/wm8994.c

@@ -3513,6 +3513,31 @@ static void wm8958_button_det(struct snd_soc_codec *codec, u16 status)
 			    wm8994->btn_mask);
 }
 
+static void wm8958_open_circuit_work(struct work_struct *work)
+{
+	struct wm8994_priv *wm8994 = container_of(work,
+						  struct wm8994_priv,
+						  open_circuit_work.work);
+	struct device *dev = wm8994->wm8994->dev;
+
+	wm1811_micd_stop(wm8994->hubs.codec);
+
+	mutex_lock(&wm8994->accdet_lock);
+
+	dev_dbg(dev, "Reporting open circuit\n");
+
+	wm8994->jack_mic = false;
+	wm8994->mic_detecting = true;
+
+	wm8958_micd_set_rate(wm8994->hubs.codec);
+
+	snd_soc_jack_report(wm8994->micdet[0].jack, 0,
+			    wm8994->btn_mask |
+			    SND_JACK_HEADSET);
+
+	mutex_unlock(&wm8994->accdet_lock);
+}
+
 static void wm8958_mic_id(void *data, u16 status)
 {
 	struct snd_soc_codec *codec = data;
@@ -3522,16 +3547,9 @@ static void wm8958_mic_id(void *data, u16 status)
 	if (!(status & WM8958_MICD_STS)) {
 		/* If nothing present then clear our statuses */
 		dev_dbg(codec->dev, "Detected open circuit\n");
-		wm8994->jack_mic = false;
-		wm8994->mic_detecting = true;
-
-		wm1811_micd_stop(codec);
 
-		wm8958_micd_set_rate(codec);
-
-		snd_soc_jack_report(wm8994->micdet[0].jack, 0,
-				    wm8994->btn_mask |
-				    SND_JACK_HEADSET);
+		schedule_delayed_work(&wm8994->open_circuit_work,
+				      msecs_to_jiffies(2500));
 		return;
 	}
 
@@ -3812,6 +3830,8 @@ static irqreturn_t wm8958_mic_irq(int irq, void *data)
 	if (!(snd_soc_read(codec, WM8958_MIC_DETECT_1) & WM8958_MICD_ENA))
 		return IRQ_HANDLED;
 
+	cancel_delayed_work_sync(&wm8994->open_circuit_work);
+
 	pm_runtime_get_sync(codec->dev);
 
 	/* We may occasionally read a detection without an impedence
@@ -3911,6 +3931,8 @@ static int wm8994_codec_probe(struct snd_soc_codec *codec)
 	mutex_init(&wm8994->accdet_lock);
 	INIT_DELAYED_WORK(&wm8994->jackdet_bootstrap,
 			  wm1811_jackdet_bootstrap);
+	INIT_DELAYED_WORK(&wm8994->open_circuit_work,
+			  wm8958_open_circuit_work);
 
 	switch (control->type) {
 	case WM8994:

sound/soc/codecs/wm8994.h

@@ -134,6 +134,7 @@ struct wm8994_priv {
 	struct mutex accdet_lock;
 	struct wm8994_micdet micdet[2];
 	struct delayed_work mic_work;
+	struct delayed_work open_circuit_work;
 	bool mic_detecting;
 	bool jack_mic;
 	int btn_mask;