Re: [PATCH 4.19 070/422] pinctrl: ingenic: Probe driver at subsys_initcall

[Paul Cercueil]

Hi Pavel,


Le jeu., nov. 21, 2019 at 11:17, Pavel Machek <pavel@xxxxxxx> a écrit :
> On Tue 2019-11-19 06:14:27, Greg Kroah-Hartman wrote:
> >  From: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> >
> >  [ Upstream commit 556a36a71ed80e17ade49225b58513ea3c9e4558 ]
> >
> >  Using postcore_initcall() makes the driver try to initialize way too
> >  early.
>
> Does it fix concrete bug / would you say it is suitable for -stable?

When using postcore_initcall() it locks up early in the boot process, 
so it definitely fixes a bug. I think it locks up because standard 
(non-early) platform drivers can't be probed postcore (but they can be 
registered and probed later).

> >  +++ b/drivers/pinctrl/pinctrl-ingenic.c
> >  @@ -847,4 +847,4 @@ static int __init 
> > ingenic_pinctrl_drv_register(void)
> >   {
> >   	return platform_driver_register(&ingenic_pinctrl_driver);
> >   }
> >  -postcore_initcall(ingenic_pinctrl_drv_register);
> >  +subsys_initcall(ingenic_pinctrl_drv_register);
>
> There are other pinctrl drivers initialized very early, do they need
> fixing, too?

The other drivers call platform_driver_register(), not 
platform_driver_probe(), which means that they will probe at the same 
time as the other platform drivers.

The reason platform_driver_probe() is used in pinctrl-ingenic is that 
it allows the probe function and all the code attached to be marked 
__init.

Cheers,
-Paul