[PATCH v9 0/4] Microchip soft ip corePWM driver

[Conor Dooley]

Hey Uwe, all,

6.0-rc1 has rolled around so here is the promised ~v8~v9.
The pre 6.0-rc1 cover letter/series is here:
https://lore.kernel.org/linux-pwm/20220721172109.941900-1-mail@conchuod.ie
I'll take the dts change myself once the rest is merged.

There is one change here that is not directly from your feedback on v7,
Iadded a test for invalid PERIOD_STEPS values, in which case we abort if
the period is locked and cannot be fixed. Hopefully the rounding is not
ruined..

Thanks,
Conor.

Changes since v8:
- fixed a(nother) raw 64 bit division (& built it for riscv32!)
- added a check to make sure we don't try to sleep for 0 us

Changes since v7:
- rebased on 6.0-rc1
- reworded comments you highlighted in v7
- fixed the overkill sleeping
- removed the unused variables in calc_duty
- added some extra comments to explain behaviours you questioned in v7
- make the mutexes un-interruptible
- fixed added the 1s you suggested for the if(period_locked) logic
- added setup of the channel_enabled shadowing
- fixed the period reporting for the negedge == posedge case in
  get_state() I had to add the enabled check, as otherwise it broke
  setting the period for the first time out of reset.
- added a test for invalid PERIOD_STEPS values, in which case we abort
  if we cannot fix the period

Changes from v6:
- Dropped an unused variable that I'd missed
- Actually check the return values of the mutex lock()s
- Re-rebased on -next for the MAINTAINERS patch (again...)

Changes from v5:
- switched to a mutex b/c we must sleep with the lock taken
- simplified the locking in apply() and added locking to get_state()
- reworked apply() as requested
- removed the loop in the period calculation (thanks Uwe!)
- add a copy of the enable registers in the driver to save on reads.
- remove the second (useless) write to sync_update
- added some missing rounding in get_state()
- couple other minor cleanups as requested in:
https://lore.kernel.org/linux-riscv/20220709160206.cw5luo7kxdshoiua@pengutronix.de/

Changes from v4:
- dropped some accidentally added files

Conor Dooley (4):
  dt-bindings: pwm: fix microchip corePWM's pwm-cells
  riscv: dts: fix the icicle's #pwm-cells
  pwm: add microchip soft ip corePWM driver
  MAINTAINERS: add pwm to PolarFire SoC entry

 .../bindings/pwm/microchip,corepwm.yaml       |   4 +-
 MAINTAINERS                                   |   1 +
 .../dts/microchip/mpfs-icicle-kit-fabric.dtsi |   2 +-
 drivers/pwm/Kconfig                           |  10 +
 drivers/pwm/Makefile                          |   1 +
 drivers/pwm/pwm-microchip-core.c              | 400 ++++++++++++++++++
 6 files changed, 416 insertions(+), 2 deletions(-)
 create mode 100644 drivers/pwm/pwm-microchip-core.c


base-commit: 568035b01cfb107af8d2e4bd2fb9aea22cf5b868
-- 
2.36.1