Re: [PATCH 4/5] thermal/core: Enforce paired .bind/.unbind callbacks

["Zhang, Rui" <rui.zhang@intel.com>]

On Fri, 2023-03-24 at 14:24 +0100, Rafael J. Wysocki wrote:
> On Fri, Mar 24, 2023 at 8:08 AM Zhang Rui <rui.zhang@intel.com>
> wrote:
> > The .bind/.unbind callbacks are designed to allow the thermal zone
> > device to bind to/unbind from a matched cooling device, with
> > thermal
> > instances created/deleted.
> > 
> > In this sense, .bind/.unbind callbacks must exist in pairs.
> > 
> > Signed-off-by: Zhang Rui <rui.zhang@intel.com>
> > ---
> >  drivers/thermal/thermal_core.c | 5 +++++
> >  1 file changed, 5 insertions(+)
> > 
> > diff --git a/drivers/thermal/thermal_core.c
> > b/drivers/thermal/thermal_core.c
> > index 5225d65fb0e0..9c447f22cb39 100644
> > --- a/drivers/thermal/thermal_core.c
> > +++ b/drivers/thermal/thermal_core.c
> > @@ -1258,6 +1258,11 @@
> > thermal_zone_device_register_with_trips(const char *type, struct
> > thermal_trip *t
> >         if (num_trips > 0 && (!ops->get_trip_type || !ops-
> > >get_trip_temp) && !trips)
> >                 return ERR_PTR(-EINVAL);
> > 
> > +       if ((ops->bind && !ops->unbind) || (!ops->bind && ops-
> > >unbind)) {
> 
> This can be written as
> 
>         if (!!ops->bind != !!ops->unbind) {
> 
> > +               pr_err("Thermal zone device .bind/.unbind not
> > paired\n");
> 
> And surely none of the existing drivers do that?  Because it would be
> a functional regression if they did.

Yeah, I did a check and all drivers provide .bind/.unbind callbacks in
pairs.

Hi, Daniel,
I know you're dealing with various of thermal drivers recently, are you
aware of any exceptions?

thanks,
rui