ASoC: generic: Free jack GPIOs on card remove

Chancel Liu <chancel.liu@oss.nxp.com> says:

simple_util_init_jack() acquires a jack detection GPIO with
gpiod_get_optional() and passes it to snd_soc_jack_add_gpios(), which
also installs an IRQ handler, a PM notifier, a delayed work and a sysfs
export for it. None of simple-card, audio-graph-card or
audio-graph-card2 implements a card->remove() callback, so none of this
is ever released.

That goes unnoticed while the card is only torn down together with its
platform device, because the devres cleanup registered by
snd_soc_jack_add_gpios() is tied to that platform device. It becomes a
problem once the card alone is unregistered and registered again while
the platform device stays bound - for instance when a codec component is
unbound and bound again. card->probe() then runs a second time and
gpiod_get_optional() fails with -EBUSY, because the descriptor is still
held by the previous bind. The card is not registered again and audio
stays broken until the platform device itself is unbound.

Patch 1 adds the simple_util_remove_jack() helper, patches 2-4 wire it
up in the three generic card drivers.

Verified with audio-graph-card2 and a wm8962 codec using hp-det-gpios.
Before the series, the first

  echo 3-001a > /sys/bus/i2c/drivers/wm8962/unbind
  echo 3-001a > /sys/bus/i2c/drivers/wm8962/bind

leaves the GPIO line and IRQ claimed while the card is gone, and the
re-bind fails with

  ASoC error (-16): at graph_util_card_probe()
  ASoC error (-16): at snd_soc_card_probe() on wm8962-audio

after which the sound card never comes back. With the series applied,
both codec unbind/bind and platform unbind/bind cycles release the GPIO
and IRQ on unbind and fully restore the card.

Link: https://patch.msgid.link/20260913102502.2805912-1-chancel.liu@oss.nxp.com

1 files changed, 2 insertions, 0 deletions

diff --git a/include/sound/simple_card_utils.h b/include/sound/simple_card_utils.h
index bd8c3a033577..68faec56970e 100644
--- a/include/sound/simple_card_utils.h
+++ b/include/sound/simple_card_utils.h
@@ -219,12 +219,14 @@ static inline int simple_util_parse_aux_devs(struct simple_util_priv *priv, char
 int simple_util_init_jack(struct snd_soc_card *card,
 			       struct simple_util_jack *sjack,
 			       int is_hp, char *prefix, char *pin);
+void simple_util_remove_jack(struct simple_util_jack *sjack);
 int simple_util_init_aux_jacks(struct snd_soc_card *card, char *prefix);
 int simple_util_init_priv(struct simple_util_priv *priv,
 			       struct link_info *li);
 void simple_util_remove(struct platform_device *pdev);
 
 int graph_util_card_probe(struct snd_soc_card *card);
+int graph_util_card_remove(struct snd_soc_card *card);
 int graph_util_is_ports0(struct device_node *port);
 int graph_util_parse_dai(struct simple_util_priv *priv, struct device_node *ep,
 			 struct snd_soc_dai_link_component *dlc, int *is_single_link);