Re: [PATCH v8 09/26] memory: tegra30: Support interconnect framework

From: Viresh Kumar
Date: Wed Nov 11 2020 - 02:54:09 EST


On 11-11-20, 10:32, Dmitry Osipenko wrote:
> 11.11.2020 09:18, Viresh Kumar пишет:
> > On 11-11-20, 09:14, Dmitry Osipenko wrote:
> >> The dev_pm_opp_of_add_table() will produce a error message which doesn't
> >> give a clue about what's wrong, i.e. that device-tree needs to be updated.
> >
> > If you think that you need to print something more, then you can do
> > that in the error message you print when dev_pm_opp_of_add_table()
> > fails. I would suggest to drop this redundant check here.
> >
>
> Please give the rationale.

The rationale is that the check is already performed by
dev_pm_opp_of_add_table() and it isn't going to add *any* benefit to
check it again here. Such a check for matching compatible platforms is
normally fine, but not for this. This is like open coding part of
dev_pm_opp_of_add_table(), and so is redundant. The
dev_pm_opp_of_add_table() helper also checks for OPPv1 bindings in the
DT (yes you won't be using them on your platform) and so relying on
that API is a better thing to do.

As you already said, you just wanted a better print message and so you
have added this check. If you really care only about the print
message, then you can add a print of your choice in the driver but
otherwise this check is not going to benefit you much I am afraid.

Having said that, this isn't the code I maintain. I need to guarantee
that the OPP core APIs are used properly and are not misused and so I
have a higher say there. But in this case all I can do is _suggest_
and not enforce. And as I said earlier, I suggest to drop this
redundant check in order to make your code better and faster.

Thanks.

--
viresh