Re: [PATCH 3/3] Documentation: ABI: sysfs-driver-regulator-output

From: Greg Kroah-Hartman
Date: Wed Sep 20 2023 - 06:48:42 EST


On Wed, Sep 20, 2023 at 03:44:29AM -0700, Zev Weiss wrote:
> On Wed, Sep 20, 2023 at 02:29:15AM PDT, Greg Kroah-Hartman wrote:
> > On Wed, Sep 20, 2023 at 02:02:49AM -0700, Zev Weiss wrote:
> > > static int regulator_userspace_notify(struct notifier_block *nb,
> > > unsigned long event,
> > > void *ignored)
> > > {
> > > struct userspace_consumer_data *data =
> > > container_of(nb, struct userspace_consumer_data, nb);
> > > - static const char * const *envp[] = { "NAME=events", NULL };
> >
> > You removed this user/kernel api value, what will break if you do that?
> >
>
> Sorry, I don't follow -- what removal are you referring to? The envp array
> still has a NAME entry -- I changed its value from "events" to "event",

Yes, that value.

> but
> I wrote that part before I realized that the 'event' parameter of the
> function was actually a bitmask that might convey multiple events and just
> forgot to change it back, so keeping it pluralized is probably more
> appropriate.
>
> And FWIW, I didn't intend for the exact format of the EVENT parameter that I
> sketched there to be something that had to be kept; given that there might
> be multiple entries perhaps it'd be better to use separate parameters more
> like NUMEVENTS, EVENT0, EVENT1, etc? (Or omit NUMEVENTS and just let the
> consumer count upward until it doesn't find a match.)

I don't know, what does userspace do with this value today? If you
change it, what will break?

thanks,

greg k-h