Re: RE: [PATCH v6 1/2] usb: dwc3: add Realtek DHC RTD SoC dwc3 glue layer driver

[Christophe JAILLET]

Le 01/11/2023 à 07:27, Stanley Chang[昌育德] a écrit :
> Hi CJ,
>
> I think these functions are not needed in remove function.
>
> In dwc3_rtk_probe_dwc3_core,
> I have used
> dwc3_node = of_get_compatible_child(node, "snps,dwc3");
> and
> dwc3_pdev = of_find_device_by_node(dwc3_node);
>
> So, I call these put functions.
> platform_device_put(dwc3_pdev);
> of_node_put(dwc3_node);

Yes, but you call it only in the error handling path of the function.

I wonder if they should also be called in the remove function in order 
to decrement the ref-counted reference.


Same in __get_dwc3_maximum_speed(), the reference taken by:
   dwc3_np = of_get_compatible_child(np, "snps,dwc3");
is never released.


See the comment at [1] to see what I mean.


[1]: https://elixir.bootlin.com/linux/v6.6/source/drivers/of/base.c#L681

CJ
> Thanks,
> Stanley
>
> > Hi,
> >
> > Is something like
> >          platform_device_put(dwc3_pdev);
> >          of_node_put(dwc3_node);
> > needed in the remove function?
> >
> > (as done in the error handling path of dwc3_rtk_probe_dwc3_core())
> >
> > Or should it be added at the end of dwc3_rtk_probe_dwc3_core() if the
> > reference are nor needed anymore when we leave the function?
> >
> > CJ
> >
> > > +     of_platform_depopulate(rtk->dev); }
> > > +
> >
> > ...