Re: [PATCH] soc/tegra: refactor soc_is_tegra()

From: Frank Lee
Date: Wed Nov 21 2018 - 09:58:17 EST


On Wed, Nov 21, 2018 at 10:56 PM Thierry Reding
<thierry.reding@xxxxxxxxx> wrote:
>
> On Wed, Nov 21, 2018 at 02:50:54PM +0000, Jon Hunter wrote:
> >
> > On 21/11/2018 14:47, Frank Lee wrote:
> > > On Wed, Nov 21, 2018 at 10:43 PM Thierry Reding
> > > <thierry.reding@xxxxxxxxx> wrote:
> > >>
> > >> On Wed, Nov 21, 2018 at 02:34:57PM +0000, Jon Hunter wrote:
> > >>>
> > >>> On 21/11/2018 14:12, Yangtao Li wrote:
> > >>>> of_find_node_by_path() acquires a reference to the node returned by
> > >>>> it and that reference needs to be dropped by its caller.soc_is_tegra()
> > >>>> doesn't do that, so fix it.Call of_machine_is_compatible() to refactor
> > >>>> soc_is_tegra() whcih automatically manages the reference count.
> > >>>>
> > >>>> Signed-off-by: Yangtao Li <tiny.windzz@xxxxxxxxx>
> > >>>> ---
> > >>>> drivers/soc/tegra/common.c | 12 +++++++-----
> > >>>> 1 file changed, 7 insertions(+), 5 deletions(-)
> > >>>>
> > >>>> diff --git a/drivers/soc/tegra/common.c b/drivers/soc/tegra/common.c
> > >>>> index cd8f41351add..0b40700b672a 100644
> > >>>> --- a/drivers/soc/tegra/common.c
> > >>>> +++ b/drivers/soc/tegra/common.c
> > >>>> @@ -22,11 +22,13 @@ static const struct of_device_id tegra_machine_match[] = {
> > >>>>
> > >>>> bool soc_is_tegra(void)
> > >>>> {
> > >>>> - struct device_node *root;
> > >>>> + struct of_device_id *match = tegra_machine_match;
> > >>>>
> > >>>> - root = of_find_node_by_path("/");
> > >>>> - if (!root)
> > >>>> - return false;
> > >>>> + while(match->compatible){
> > >>>> + if(of_machine_is_compatible(match->compatible))
> > >>>> + return true;
> > >>>> + match++;
> > >>>> + }
> > >>>>
> > >>>> - return of_match_node(tegra_machine_match, root) != NULL;
> > >>>> + return false;
> > >>>> }
> > >>>
> > >>> Ugh ... sorry, I thought that of_machine_is_compatible() looped through
> > >>> the matches. OK, let's stick with your initial fix.
> > >>
> > >> Actually I prefer this one. Even if it is slightly more verbose, I think
> > >> it's much clearer what's actually going on. Also this hides all of the
> > >> OF node reference counting in a core function, so it's worth the extra
> > >> line, in my opinion.
> > >>
> > >> Thierry
> > > Hi Jonï
> > >
> > > I like both, how aboout you?
> >
> > Yes fine with me too. However, looks like there is some formatting that
> > needs to be fixed up above. Please make sure you run checkpatch.pl on
> > your patches. Otherwise ...
> >
> > Acked-by: Jon Hunter <jonathanh@xxxxxxxxxx>
> >
> > Thierry, pick up this version if you prefer.
>
> Yeah, I noticed the formatting issues, but I can take care of them while
> applying.
>
> Thanks,
> Thierry
Thierryï

Thanks. :-)

Yours,
Yangtao