polls periodically until a condition is met or a timeout is reached.
By using the function, the 8th patch fixes QT2025 PHY driver to sleep
until the hardware becomes ready.

As a result of the past discussion, this introduces a new type
representing a span of time instead of using core::time::Duration or
time::Ktime.

Unlike the old rust branch, This adds a wrapper for fsleep() instead
of msleep(). fsleep() automatically chooses the best sleep method
based on a duration.

v3:
- Update time::Delta methods (use i64 for everything)
- Fix read_poll_timeout to show the proper debug info (file and line)
- Move fsleep to rust/kernel/time/delay.rs
- Round up delta for fsleep
- Access directly ktime_t instead of using ktime APIs
- Add Eq and Ord with PartialEq and PartialOrd
v2: https://lore.kernel.org/lkml/20241005122531.20298-1-fujita.tomonori@gmail.com/ (local)
- Introduce time::Delta instead of core::time::Duration
- Add some trait to Ktime for calculating timeout
- Use read_poll_timeout in QT2025 driver instead of using fsleep directly
v1: https://lore.kernel.org/netdev/20241001112512.4861-1-fujita.tomonori@gmail.com/ (local)

FUJITA Tomonori (8):
  rust: time: Add PartialEq/Eq/PartialOrd/Ord trait to Ktime
  rust: time: Introduce Delta type
  rust: time: Change output of Ktime's sub operation to Delta
  rust: time: Implement addition of Ktime and Delta
  rust: time: Add wrapper for fsleep function
  MAINTAINERS: rust: Add TIMEKEEPING and TIMER abstractions
  rust: Add read_poll_timeout functions
  net: phy: qt2025: Wait until PHY becomes ready

 MAINTAINERS               |  2 +
 drivers/net/phy/qt2025.rs | 10 +++-
 rust/helpers/helpers.c    |  2 +
 rust/helpers/kernel.c     | 13 +++++
 rust/helpers/time.c       |  8 ++++
 rust/kernel/error.rs      |  1 +
 rust/kernel/io.rs         |  5 ++
 rust/kernel/io/poll.rs    | 84 +++++++++++++++++++++++++++++++++
 rust/kernel/lib.rs        |  1 +
 rust/kernel/time.rs       | 99 ++++++++++++++++++++++++++++++++++++---
 rust/kernel/time/delay.rs | 31 ++++++++++++
 11 files changed, 249 insertions(+), 7 deletions(-)
 create mode 100644 rust/helpers/kernel.c
 create mode 100644 rust/helpers/time.c
 create mode 100644 rust/kernel/io.rs
 create mode 100644 rust/kernel/io/poll.rs
 create mode 100644 rust/kernel/time/delay.rs


base-commit: 068f3b34c5c2be5fe7923a9966c1c16f992a2f9c
-- 
2.43.0