Re: [PATCH v2 1/2] driver core: make fwnode_is_primary() public

[Andy Shevchenko]

On Mon, Feb 23, 2026 at 08:45:42PM +0100, Rafael J. Wysocki wrote:
> On Mon, Feb 23, 2026 at 8:32 PM Andy Shevchenko
> <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> > On Mon, Feb 23, 2026 at 07:28:48PM +0100, Bartosz Golaszewski wrote:
> > > On Mon, Feb 23, 2026 at 6:54 PM Andy Shevchenko
> > > <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> > > > On Mon, Feb 23, 2026 at 04:40:52PM +0100, Bartosz Golaszewski wrote:
> > > > > Export fwnode_is_primary() in fwnode.h for use in driver code.

...

> > > > > --- a/include/linux/fwnode.h
> > > > > +++ b/include/linux/fwnode.h
> > > > > @@ -230,4 +230,9 @@ void fwnode_links_purge(struct fwnode_handle *fwnode);
> > > > >  void fw_devlink_purge_absent_suppliers(struct fwnode_handle *fwnode);
> > > > >  bool fw_devlink_is_strict(void);
> > > > >
> > > > > +static inline bool fwnode_is_primary(struct fwnode_handle *fwnode)
> > > > > +{
> > > > > +     return fwnode && !IS_ERR(fwnode->secondary);
> > > > > +}
> > > >
> > > > This is inconsistent. Please, split out fwnode stuff from device.h to
> > > > device/fwnode.h and share it there.
> > > >
> > > > This reminds me to look what I have locally in development...
> > > >
> > > > (With your patch it will be in device.h and fwnode.h and in the latter
> > > >  it's even not properly grouped with other non-fwdevlink related stuff.)
> > >
> > > Please rephrase the entire email because I have no idea what you mean. :(
> >
> > The primary/secondary and other device-fwnode related stuff is currently
> > exposed via include/linux/device.h. The problem is that device.h is overloaded
> > and starves for more splitting, which I'm doing (very slowly, though).
> > The idea is to have all device-fwnode  (and maybe of_node) stuff to be gathered in
> > include/linux/device/fwnode.h
> 
> I don't see "struct device" anywhere in fwnode_is_primary().  This
> check is only about whether or not the given fwnode has a valid
> secondary fwnode.

I am talking about splitting device-fwnode related API to
include/linux/device/fwnode.h. The idea of primary/secondary comes from the
upper layer (device) as struct fwnode_handle just defines a 'secondary' member
for a single linked list. It doesn't seem to limit anyhow the list.

My understanding is that the fwnode_is_primary() belongs to the device layer more
than to fwnode one. fwnode layer doesn't (clearly?) define the use cases
and in my opinion should not, fwnode_handle is more abstract and shouldn't
be limited to primary/secondary division that is currently related to the
device. Maybe I am missing something obvious... but to me spreading these
APIs into fwnode.h sounds like layering violation (especially if we think
of the future decoupling fwnode from struct device and making it a separate
entity).

> > You, guys, missed the keyword 'device' in the pathname for the proposed
> > [include/linux/device/]fwnode.h.
> 
> Why do you think we missed it?

Because of the previous comment that suggest that I wanted to move the code to
fwnode.h, but I was talking about device/fwnode.h (which is currently absent).

-- 
With Best Regards,
Andy Shevchenko