Re: [PATCH v6 1/1] serial: core: Start managing serial controllers to enable runtime PM

Tony Lindgren
2023-03-10T06:52:08Z

* Tony Lindgren <tony@atomide.com> [230309 13:07]:
> * Andy Shevchenko <andriy.shevchenko@intel.com> [230309 12:23]:
> > On Thu, Mar 09, 2023 at 10:57:08AM +0200, Tony Lindgren wrote:
> > > + err = pm_runtime_get(port_dev);
> >
> > Is not sync API a deliberate choice? Do we need to comment on why is so?
>
> I don't think it can be sync version.. See where all __uart_start() may
> get called from. The pm_runtime_get() here is needed so the check for
> pm_runtime_active() won't be racy. Maybe we can now leave out the
> "start TX anyways" part though.

To clarify, the reason we no longer need the check for "start TX anyways"
is we now do pm_runtime_get() on the new port_dev. Earlier we tried to do
it on the physical serial port driver dev where runtime PM possibly was
not enabled.

Regards,

Tony