Re: [PATCH v2 1/5] pinctrl: Allow modules to use pinctrl_[un]register_mappings

[Hans de Goede]

Hi,

On 30-12-2019 14:31, Linus Walleij wrote:
> On Mon, Dec 16, 2019 at 9:51 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> > Currently only the drivers/pinctrl/devicetree.c code allows registering
> > pinctrl-mappings which may later be unregistered, all other mappings
> > are assumed to be permanent.
> >
> > Non-dt platforms may also want to register pinctrl mappings from code which
> > is build as a module, which requires being able to unregister the mapping
> > when the module is unloaded to avoid dangling pointers.
> >
> > To allow unregistering the mappings the devicetree code uses 2 internal
> > functions: pinctrl_register_map and pinctrl_unregister_map.
> >
> > pinctrl_register_map allows the devicetree code to tell the core to
> > not memdup the mappings as it retains ownership of them and
> > pinctrl_unregister_map does the unregistering, note this only works
> > when the mappings where not memdupped.
> >
> > The only code relying on the memdup/shallow-copy done by
> > pinctrl_register_mappings is arch/arm/mach-u300/core.c this commit
> > replaces the __initdata with const, so that the shallow-copy is no
> > longer necessary.
> >
> > After that we can get rid of the internal pinctrl_unregister_map function
> > and just use pinctrl_register_mappings directly everywhere.
> >
> > This commit also renames pinctrl_unregister_map to
> > pinctrl_unregister_mappings so that its naming matches its
> > pinctrl_register_mappings counter-part and exports it.
> >
> > Together these 2 changes will allow non-dt platform code to
> > register pinctrl-mappings from modules without breaking things on
> > module unload (as they can now unregister the mapping on unload).
> >
> > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
>
> This v2 works fine for me, I applied it to this immutable branch in the
> pinctrl tree:
> https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl.git/log/?h=ib-pinctrl-unreg-mappings
>
> And pulled that into the pinctrl "devel" branch for v5.6.
>
> Please pull this immutable branch into the Intel DRM tree and apply
> the rest of the stuff on top!

Great, thank you!

Regards,

Hans

p.s.

Happy New year everyone.