Re: [PATCH v13 12/18] platform: Add __free() based cleanup function for platform_device_put

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Oct 14, 2024 at 04:43:39PM +0100, Jonathan Cameron wrote:
> On Wed, 9 Oct 2024 13:41:13 +0100
> <shiju.jose@huawei.com> wrote:
> 
> > From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> > 
> > Add __free() based cleanup function for platform_device_put().
> > 
> > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> > Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
> > ---
> >  include/linux/platform_device.h | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
> > index d422db6eec63..606533b88f44 100644
> > --- a/include/linux/platform_device.h
> > +++ b/include/linux/platform_device.h
> > @@ -232,6 +232,7 @@ extern int platform_device_add_data(struct platform_device *pdev,
> >  extern int platform_device_add(struct platform_device *pdev);
> >  extern void platform_device_del(struct platform_device *pdev);
> >  extern void platform_device_put(struct platform_device *pdev);
> > +DEFINE_FREE(platform_device_put, struct platform_device *, if (_T) platform_device_put(_T))
> >  
> >  struct platform_driver {
> >  	int (*probe)(struct platform_device *);
> 
> +CC Greg KH and Rafael.
> 
> Makes sure to include them on v14 as this needs review from a driver core point
> of view I think.

Why is this needed for a platform device?  This feels like you will have
to do more work to "keep" the reference on the normal path than you to
today to release the reference on the error path, right?  Have a pointer
to a patch that uses this?

thanks,

greg k-h