ASoC: rt5651: Fix workqueue cancel vs irq free race on remove
authorHans de Goede <hdegoede@redhat.com>
Wed, 4 Jul 2018 22:59:31 +0000 (00:59 +0200)
committerMark Brown <broonie@kernel.org>
Tue, 10 Jul 2018 17:49:24 +0000 (18:49 +0100)
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@endlessm.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
sound/soc/codecs/rt5651.c

index 6b5669f..39d2c67 100644 (file)
@@ -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);