The following has been changed:
- introduce a new C serdev API to fix race conditions and simplify rust
  code. Should also be useful on the C side.
- fix race conditions
- simplify rust code
- add rust function to provide mutable references to driver's private
  data
- provide mutable references in callbacks to avoid the need for a
  SpinLock in the greybus patch series [1]

[1]
https://lore.kernel.org/rust-for-linux/20260827-gb-uart-transport-v2-7-a03bb1f5fbd1@beagleboard.org/

Signed-off-by: Markus Probst <markus.probst@posteo.de>
---
Markus Probst (5):
      tty: serdev: Export functions to pause receive_buf callback calls
      rust: serdev: Replace `active` mutex with receive pause
      rust: serdev: Simplify callbacks
      rust: Add `Device::drvdata_borrow_mut`
      rust: serdev: Pause receive callback before calling unbind

 drivers/tty/serdev/core.c           |  50 +++++++++-
 drivers/tty/serdev/serdev-ttyport.c |  32 ++++++
 include/linux/serdev.h              |   6 ++
 rust/kernel/device.rs               |  24 +++++
 rust/kernel/serdev.rs               | 189 +++++++++++++-----------------------
 samples/rust/rust_driver_serdev.rs  |   2 +-
 6 files changed, 180 insertions(+), 123 deletions(-)
---
base-commit: e5e04726cdd043e309677071ab1b65a4b18f422b
change-id: 20260905-rust_serdev_probe_refactor-0e2b044354a7