Re: [PATCH 2/2] serial: core: fix console port-lock regression

[Andy Shevchenko]

On Mon, Sep 14, 2020 at 11:09:16AM +0300, Tony Lindgren wrote:
> * Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> [200910 09:27]:
> > +Cc: Tony, let me add Tony to the discussion.
> > 
> > On Thu, Sep 10, 2020 at 09:35:27AM +0200, Johan Hovold wrote:
> > > And what about power management
> > > which was the reason for wanting this on OMAP in the first place; tty
> > > core never calls shutdown() for a console port, not even when it's been
> > > detached using the new interface.
> > 
> > That is interesting... Tony, do we have OMAP case working because of luck?
> 
> 8250_omap won't do anything unless autosuspend_timeout is configured for
> the uart(s). If configured, then the 8250_omap will idle when console is
> detached and the PM runtime usage count held by console is decremented, and
> the configured autosuspend_timeout expires.
> 
> The console is still kept open by getty, so I don't see why shutdown() would
> be called for the console port. But maybe I don't follow what you're
> concerned about, let me know if you want me to check something :)

Is it possible to test configuration when you have kernel console enabled but
no getty is run on it (perhaps something with ssh enabled access)?

Then kernel console should call ->shutdown on detaching, right?

-- 
With Best Regards,
Andy Shevchenko