Re: [PATCH 0/8] IIO: Where dev_pm_ops rework and namespaces meet.

Jonathan Cameron
2022-02-23T12:13:52Z

On Wed, 23 Feb 2022 11:50:48 +0000
Paul Cercueil <paul@crapouillou.net> wrote:

> Hi Jonathan,
>
> Le dim., févr. 20 2022 at 18:15:14 +0000, Jonathan Cameron
> <jic23@kernel.org> a écrit :
> > From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> >
> > Hi All,
> >
> > As these two activities have been ongoing across IIO at the same time
> > it was inevitable that there would be drivers were they both interact.
> > In particularly when we have EXPORT* of struct dev_pm_ops.
> >
> > This series covers those cases by introducing (in patch 2)
> > EXPORT_NS[_GPL]_SIMPLE_DEV_PM_OPS() and
> > EXPORT_NS[_GPL]_RUNTIME_DEV_PM_OPS()
> > that add a namespace as the final parameter.
>
> If we now have namespace versions of the macros, I'm starting to wonder
> if the original macros are still useful.
>
> In which case would we need to export a dev_pm_ops outside the scope of
> a namespace?

Excellent point. Long term my assumption is that any place where
a dev_pm_ops is being exported probably should be in a namespace
because the scope is tightly defined.

My only thought is it adds a burden to moving over to your new infrastructure
as it would be odd to move only the dev_pm_ops into a NS without looking
at the rest of the exports in a driver.

It was useful to be able to do things in two steps as it allowed separation
of using the new dev_pm_ops handling from a namespace move, but
clearly could do that the other way around and not need the non
namespaced version of this macro.
So do namespace move first then use the new macros and hence only
ever need the namespaced one.

Jonathan

>
> Cheers,
> -Paul
>
> > In each driver (with the exception of the kxsd9 which was already
> > using a IIO_KXSD9 namespace) I first move to the new *_PM_OPS()
> > and pm_[sleep_]_ptr() then in a second patch move to the new
> > namespaces. Initially I had these two steps done as one patch
> > per driver but that was harder to follow and broke the rule of
> > one thing per patch.
> >
> > All comments welcome.
> >
> > Thanks,
> >
> > Jonathan
> >
> > Jonathan Cameron (8):
> > iio: chemical: scd30: Export dev_pm_ops instead of suspend() and
> > resume()
> > PM: core: Add NS varients of EXPORT[_GPL]_SIMPLE_DEV_PM_OPS and
> > runtime pm equiv
> > iio: chemical: scd30: Move symbol exports into IIO_SCD30 namespace
> > iio:accel:kxsd9: Switch from CONFIG_PM guards to pm_ptr() etc
> > iio: humidity: hts221: Use EXPORT_SIMPLE_DEV_PM_OPS() to allow
> > compiler to remove dead code.
> > iio: humidity: hts221: Move symbol exports into IIO_HTS221 namespace
> > iio: imu: lsm6dsx: Use new pm_sleep_ptr() and
> > EXPORT_SIMPLE_DEV_PM_OPS()
> > iio: imu: lsm6dsx: Move exported symbols to the IIO_LSM6DSX
> > namespace
> >
> > drivers/iio/accel/kxsd9-i2c.c | 2 +-
> > drivers/iio/accel/kxsd9-spi.c | 2 +-
> > drivers/iio/accel/kxsd9.c | 11 ++---------
> > drivers/iio/chemical/scd30.h | 5 +----
> > drivers/iio/chemical/scd30_core.c | 10 +++++-----
> > drivers/iio/chemical/scd30_i2c.c | 3 ++-
> > drivers/iio/chemical/scd30_serial.c | 3 ++-
> > drivers/iio/humidity/hts221_core.c | 12 +++++-------
> > drivers/iio/humidity/hts221_i2c.c | 3 ++-
> > drivers/iio/humidity/hts221_spi.c | 3 ++-
> > drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 12 +++++-------
> > drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c | 3 ++-
> > drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i3c.c | 3 ++-
> > drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_spi.c | 3 ++-
> > include/linux/pm.h | 14 +++++++++-----
> > include/linux/pm_runtime.h | 10 ++++++++--
> > 16 files changed, 51 insertions(+), 48 deletions(-)
> >
> > --
> > 2.35.1
> >
>
>