[PATCH v4 resend 02/13] extcon: arizona: Fix some issues when HPDET IRQ fires after the jack has been unplugged

[Hans de Goede]

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.

Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Acked-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
Tested-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
 drivers/extcon/extcon-arizona.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/extcon/extcon-arizona.c b/drivers/extcon/extcon-arizona.c
index aae82db542a5..f7ef247de46a 100644
--- a/drivers/extcon/extcon-arizona.c
+++ b/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);
-- 
2.29.2