Re: [PATCH togreg v4 0/2] iio: imu: inv_icm42607: fix PM error handling

[Kanak Shilledar]

> The recently queued ICM-42607 PM support has two error paths that can leave
> the PM core's state inconsistent with the device.
> 
> Patch 1 propagates sensor shutdown failures from runtime suspend.  Patch 2
> ensures that system resume restores runtime PM management on both of its
> error paths, so that a failed resume does not leave runtime PM disabled for
> good.
> 
> Changes since v3:
> - Patch 1: commit message expanded with the practical effect of the current
>   behaviour, the cost of propagating the error, and a description of the
>   recovery path that does not assume a particular regmap bus
>   implementation.  No code change.
> - Patch 2: unchanged.
> 
> Neither patch was reproduced on hardware; both were found by code
> inspection.  They were compile-tested with W=1 and checked with smatch.
> 
> Whether patch 1 is worth making is still a fair question - it trades a
> possible idle power leak that may be cleared by a later successful access
> for a runtime PM error state that needs an explicit reset.  The commit
> message spells that out; happy to drop it if you would rather not take
> that trade.
> 
> Linmao Li (2):
>   iio: imu: inv_icm42607: propagate runtime suspend errors
>   iio: imu: inv_icm42607: restore runtime PM on system resume errors
> 
>  .../iio/imu/inv_icm42607/inv_icm42607_core.c  | 38 ++++++++++++++-----
>  1 file changed, 29 insertions(+), 9 deletions(-)
> 
> base-commit: 350d1fb9204b13c5f95e511e98b8bcb47574d425
> --
> 2.25.1

Tested on Invensense, ICM-42370-P development board. Performed testing
with basic r/w to the device and checking the PM runtime status. It
worked as expeted.

Tested-by: Kanak Shilledar <kanak.shilledar@xxxxxxxx>

-- 
Kanak Shilledar <kanak.shilledar@xxxxxxxx>