[PATCH 5.4 05/64] ASoC: rt5682: do not block workqueue if card is unbound

[Greg Kroah-Hartman]

From: Kai Vehmanen <kai.vehmanen@xxxxxxxxxxxxxxx>

[ Upstream commit 4c33de0673ced9c7c37b3bbd9bfe0fda72340b2a ]

The current rt5682_jack_detect_handler() assumes the component
and card will always show up and implements an infinite usleep
loop waiting for them to show up.

This does not hold true if a codec interrupt (or other
event) occurs when the card is unbound. The codec driver's
remove  or shutdown functions cannot cancel the workqueue due
to the wait loop. As a result, code can either end up blocking
the workqueue, or hit a kernel oops when the card is freed.

Fix the issue by rescheduling the jack detect handler in
case the card is not ready. In case card never shows up,
the shutdown/remove/suspend calls can now cancel the detect
task.

Signed-off-by: Kai Vehmanen <kai.vehmanen@xxxxxxxxxxxxxxx>
Reviewed-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@xxxxxxxxxxxxxxx>
Reviewed-by: Shuming Fan <shumingf@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220207153000.3452802-3-kai.vehmanen@xxxxxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 sound/soc/codecs/rt5682.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/sound/soc/codecs/rt5682.c b/sound/soc/codecs/rt5682.c
index 05e883a65d7a7..a8cf4c7451304 100644
--- a/sound/soc/codecs/rt5682.c
+++ b/sound/soc/codecs/rt5682.c
@@ -1052,11 +1052,13 @@ static void rt5682_jack_detect_handler(struct work_struct *work)
 		container_of(work, struct rt5682_priv, jack_detect_work.work);
 	int val, btn_type;
 
-	while (!rt5682->component)
-		usleep_range(10000, 15000);
-
-	while (!rt5682->component->card->instantiated)
-		usleep_range(10000, 15000);
+	if (!rt5682->component || !rt5682->component->card ||
+	    !rt5682->component->card->instantiated) {
+		/* card not yet ready, try later */
+		mod_delayed_work(system_power_efficient_wq,
+				 &rt5682->jack_detect_work, msecs_to_jiffies(15));
+		return;
+	}
 
 	mutex_lock(&rt5682->calibrate_mutex);
 
-- 
2.34.1