[PATCH AUTOSEL 4.18 76/92] ASoC: rt5651: Fix workqueue cancel vs irq free race on remove

From: Sasha Levin
Date: Fri Sep 14 2018 - 21:46:30 EST


From: Hans de Goede <hdegoede@xxxxxxxxxx>

[ Upstream commit 8d2d7bcdc1645dc243f7735278675b083c0e506c ]

On removal we must free the IRQ *before* cancelling the jack-detect work,
so that the jack-detect work cannot be rescheduled by the IRQ.

Before this commit we were cancelling the jack-detect work from the
driver remove callback, while relying on devm to free the IRQ, which
happens after the remove callback.

This is the wrong order. This commit uses a devm-action to register
a devm callback which cancels the work, before requesting the IRQ
(devm tears things down in reverse order). This also allows us to
remove the now empty remove driver callback.

Cc: Carlo Caione <carlo@xxxxxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
sound/soc/codecs/rt5651.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/sound/soc/codecs/rt5651.c b/sound/soc/codecs/rt5651.c
index 6b5669f3e85d..39d2c67cd064 100644
--- a/sound/soc/codecs/rt5651.c
+++ b/sound/soc/codecs/rt5651.c
@@ -1696,6 +1696,13 @@ static irqreturn_t rt5651_irq(int irq, void *data)
return IRQ_HANDLED;
}

+static void rt5651_cancel_work(void *data)
+{
+ struct rt5651_priv *rt5651 = data;
+
+ cancel_work_sync(&rt5651->jack_detect_work);
+}
+
static int rt5651_set_jack(struct snd_soc_component *component,
struct snd_soc_jack *hp_jack, void *data)
{
@@ -2036,6 +2043,11 @@ static int rt5651_i2c_probe(struct i2c_client *i2c,

INIT_WORK(&rt5651->jack_detect_work, rt5651_jack_detect_work);

+ /* Make sure work is stopped on probe-error / remove */
+ ret = devm_add_action_or_reset(&i2c->dev, rt5651_cancel_work, rt5651);
+ if (ret)
+ return ret;
+
ret = devm_snd_soc_register_component(&i2c->dev,
&soc_component_dev_rt5651,
rt5651_dai, ARRAY_SIZE(rt5651_dai));
@@ -2043,15 +2055,6 @@ static int rt5651_i2c_probe(struct i2c_client *i2c,
return ret;
}

-static int rt5651_i2c_remove(struct i2c_client *i2c)
-{
- struct rt5651_priv *rt5651 = i2c_get_clientdata(i2c);
-
- cancel_work_sync(&rt5651->jack_detect_work);
-
- return 0;
-}
-
static struct i2c_driver rt5651_i2c_driver = {
.driver = {
.name = "rt5651",
@@ -2059,7 +2062,6 @@ static struct i2c_driver rt5651_i2c_driver = {
.of_match_table = of_match_ptr(rt5651_of_match),
},
.probe = rt5651_i2c_probe,
- .remove = rt5651_i2c_remove,
.id_table = rt5651_i2c_id,
};
module_i2c_driver(rt5651_i2c_driver);
--
2.17.1