From: Chancel Liu <chancel.liu@nxp.com>
Several ASoC codec drivers set up per-device resources from their ASoC
component probe, but the associated cleanup is tied to the underlying bus
(I2C/SPI) device rather than being balanced per component probe. This is
fine for a plain probe/remove, but it breaks when the sound card is
unregistered and re-registered while the bus device stays bound (a card
re-bind): the component probe runs again while the previous bus-level
resources are still live.
Two kinds of resources are affected:
- Regulator disable notifiers (wm8962, wm8995, tlv320aic31xx,
tlv320aic3x)
The same notifier_block is re-registered on the
still-registered regulator notifier chain, which triggers
notifier callback ..._regulator_event_N already registered
WARNING: ... at kernel/notifier.c:23 notifier_chain_register
and corrupts the chain.
- Beep input devices (wm8962, cs42l52, cs42l56)
A new input device is allocated and registered on every component
probe while the free path only clears the pointer, leaking the
previous input device and its sysfs/input node.
The two problems need opposite fixes: the notifiers are registered from
the component probe, so the registration is moved to the bus probe so it
runs once per bus bind; the beep device is freed from the component
remove path, so it is switched from devm_input_allocate_device() to
input_allocate_device() paired with an explicit
input_unregister_device() on that same free path.
Verified with wm8962. The remaining patches fix other codec drivers
following the same patterns.
Chancel Liu (6):
ASoC: wm8962: Fix regulator notifier and beep leaks on card re-bind
ASoC: wm8995: Register regulator notifiers from the bus probe
ASoC: tlv320aic31xx: Register regulator notifier from the I2C probe
ASoC: tlv320aic3x: Register regulator notifier from the bus probe
ASoC: cs42l52: Fix beep input device leak on card re-bind
ASoC: cs42l56: Fix beep input device leak on card re-bind
sound/soc/codecs/cs42l52.c | 9 ++++--
sound/soc/codecs/cs42l56.c | 9 ++++--
sound/soc/codecs/tlv320aic31xx.c | 30 +++++++++---------
sound/soc/codecs/tlv320aic3x.c | 28 ++++++++---------
sound/soc/codecs/wm8962.c | 52 +++++++++++++++++---------------
sound/soc/codecs/wm8995.c | 41 ++++++++++++++++---------
6 files changed, 96 insertions(+), 73 deletions(-)
--
2.50.1