extcon: arizona: Add some debounce time before starting HPDET identification

The HPDET identification method does not have the same natural debounce
built into it that the standard MICDET method does so add some extra on
top of what the jack detection does in hardware to make sure we get a
robust result.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/extcon/extcon-arizona.c

@@ -53,6 +53,8 @@ struct arizona_extcon_info {
 	bool micd_reva;
 	bool micd_clamp;
 
+	struct delayed_work hpdet_work;
+
 	bool hpdet_active;
 
 	int num_hpdet_res;
@@ -640,7 +642,7 @@ static void arizona_start_hpdet_acc_id(struct arizona_extcon_info *info)
 	dev_dbg(arizona->dev, "Starting identification via HPDET\n");
 
 	/* Make sure we keep the device enabled during the measurement */
-	pm_runtime_get(info->dev);
+	pm_runtime_get_sync(info->dev);
 
 	info->hpdet_active = true;
 
@@ -813,6 +815,17 @@ static irqreturn_t arizona_micdet(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
+static void arizona_hpdet_work(struct work_struct *work)
+{
+	struct arizona_extcon_info *info = container_of(work,
+							struct arizona_extcon_info,
+							hpdet_work.work);
+
+	mutex_lock(&info->lock);
+	arizona_start_hpdet_acc_id(info);
+	mutex_unlock(&info->lock);
+}
+
 static irqreturn_t arizona_jackdet(int irq, void *data)
 {
 	struct arizona_extcon_info *info = data;
@@ -822,6 +835,8 @@ static irqreturn_t arizona_jackdet(int irq, void *data)
 
 	pm_runtime_get_sync(info->dev);
 
+	cancel_delayed_work_sync(&info->hpdet_work);
+
 	mutex_lock(&info->lock);
 
 	if (arizona->pdata.jd_gpio5) {
@@ -857,7 +872,8 @@ static irqreturn_t arizona_jackdet(int irq, void *data)
 
 			arizona_start_mic(info);
 		} else {
-			arizona_start_hpdet_acc_id(info);
+			schedule_delayed_work(&info->hpdet_work,
+					      msecs_to_jiffies(250));
 		}
 
 		regmap_update_bits(arizona->regmap,
@@ -927,6 +943,7 @@ static int arizona_extcon_probe(struct platform_device *pdev)
 	mutex_init(&info->lock);
 	info->arizona = arizona;
 	info->dev = &pdev->dev;
+	INIT_DELAYED_WORK(&info->hpdet_work, arizona_hpdet_work);
 	platform_set_drvdata(pdev, info);
 
 	switch (arizona->type) {
@@ -1173,6 +1190,7 @@ static int arizona_extcon_remove(struct platform_device *pdev)
 	arizona_free_irq(arizona, ARIZONA_IRQ_MICDET, info);
 	arizona_free_irq(arizona, jack_irq_rise, info);
 	arizona_free_irq(arizona, jack_irq_fall, info);
+	cancel_delayed_work_sync(&info->hpdet_work);
 	regmap_update_bits(arizona->regmap, ARIZONA_JACK_DETECT_ANALOGUE,
 			   ARIZONA_JD1_ENA, 0);
 	arizona_clk32k_disable(arizona);