[PATCH v2 0/3] Allow SoundWire devices to communicate during remove

[Charles Keepax]

Currently on Intel systems SoundWire drivers can't communicate with the
device during driver removal. This is primarily because the IRQs are
disabled before the driver remove callback is run. The result of this is
such transactions timeout causing a) a lot of errors in the log and b)
driver remove to take a very long time.

This issue affects cs42l43 and cs42l45, primarily due to both using
regmap IRQ.

 soundwire_intel soundwire_intel.link.0: IO transfer timed out, cmd 3 device 6 addr 5d len 1
 soundwire sdw-master-0-0: trf on Slave 6 failed:-110 write addr 5d count 0
 sdca_class sdw:0:0:01fa:4245:01: Failed to sync masks in 5d

As regmap IRQ is torn down it will mask the interrupts that are
removed. However, there are many valid reasons a driver might want
communicate with the device during removal, others would include
disabling jack detection, putting the device into the lowest possible
power state to save power, etc.

This patch set attempts to address this problem trying to locate the
reason interrupts are disabled, fixing that and then leaving the IRQs
enabled for the remove callback.

Thanks,
Charles

Changes since v1:
 - Add a new helper to destroy the children on the bus separately, this
   allows the IRQs to be disabled for final cleanup.
 - Split device_unregister into device_del and put_device.

Changes since v1:
 - Add a new helper to destroy the children on the bus separately, this
   allows the IRQs to be disabled for final cleanup.
 - Split device_unregister into device_del and put_device.

Charles Keepax (3):
  soundwire: bus: Don't unassign dev_num before unregistering device
  soundwire: bus: Expose a helper to remove devices from the bus
  soundwire: intel_auxdevice: Don't disable IRQs before removing
    children

 drivers/soundwire/bus.c             | 45 +++++++++++++++++++++--------
 drivers/soundwire/intel.h           |  1 +
 drivers/soundwire/intel_auxdevice.c |  7 ++++-
 drivers/soundwire/intel_init.c      | 21 ++++++++++++++
 include/linux/soundwire/sdw.h       |  1 +
 include/linux/soundwire/sdw_intel.h |  1 +
 6 files changed, 63 insertions(+), 13 deletions(-)

-- 
2.47.3