extcon: arizona: Fix some issues when HPDET IRQ fires after the jack has been unplugged

When the jack is partially inserted and then removed again it may be
removed while the hpdet code is running. In this case the following
may happen:

1. The "JACKDET rise" or ""JACKDET fall" IRQ triggers
2. arizona_jackdet runs and takes info->lock
3. The "HPDET" IRQ triggers
4. arizona_hpdet_irq runs, blocks on info->lock
5. arizona_jackdet calls arizona_stop_mic() and clears info->hpdet_done
6. arizona_jackdet releases info->lock
7. arizona_hpdet_irq now can continue running and:
7.1 Calls arizona_start_mic() (if a mic was detected)
7.2 sets info->hpdet_done

Step 7 is undesirable / a bug:
7.1 causes the device to stay in a high power-state (with MICVDD enabled)
7.2 causes hpdet to not run on the next jack insertion, which in turn
    causes the EXTCON_JACK_HEADPHONE state to never get set

This fixes both issues by skipping these 2 steps when arizona_hpdet_irq
runs after the jack has been unplugged.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Tested-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/extcon/extcon-arizona.c

@@ -601,7 +601,7 @@ static irqreturn_t arizona_hpdet_irq(int irq, void *data)
 	struct arizona *arizona = info->arizona;
 	int id_gpio = arizona->pdata.hpdet_id_gpio;
 	unsigned int report = EXTCON_JACK_HEADPHONE;
-	int ret, reading;
+	int ret, reading, state;
 	bool mic = false;
 
 	mutex_lock(&info->lock);
@@ -614,12 +614,11 @@ static irqreturn_t arizona_hpdet_irq(int irq, void *data)
 	}
 
 	/* If the cable was removed while measuring ignore the result */
-	ret = extcon_get_state(info->edev, EXTCON_MECHANICAL);
-	if (ret < 0) {
-		dev_err(arizona->dev, "Failed to check cable state: %d\n",
-			ret);
+	state = extcon_get_state(info->edev, EXTCON_MECHANICAL);
+	if (state < 0) {
+		dev_err(arizona->dev, "Failed to check cable state: %d\n", state);
 		goto out;
-	} else if (!ret) {
+	} else if (!state) {
 		dev_dbg(arizona->dev, "Ignoring HPDET for removed cable\n");
 		goto done;
 	}
@@ -667,7 +666,7 @@ static irqreturn_t arizona_hpdet_irq(int irq, void *data)
 		gpio_set_value_cansleep(id_gpio, 0);
 
 	/* If we have a mic then reenable MICDET */
-	if (mic || info->mic)
+	if (state && (mic || info->mic))
 		arizona_start_mic(info);
 
 	if (info->hpdet_active) {
@@ -675,7 +674,9 @@ static irqreturn_t arizona_hpdet_irq(int irq, void *data)
 		info->hpdet_active = false;
 	}
 
-	info->hpdet_done = true;
+	/* Do not set hp_det done when the cable has been unplugged */
+	if (state)
+		info->hpdet_done = true;
 
 out:
 	mutex_unlock(&info->lock);