Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1386386

Re: [PATCH 10/10] cpufreq: mvebu: Use generic platdev driver

Show all headers | View raw

On Monday 25 April 2016 08:30:41 Viresh Kumar wrote:
> On 23-04-16, 00:42, Arnd Bergmann wrote:
> > On Thursday 21 April 2016 14:29:02 Viresh Kumar wrote:
> > > diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c
> > > index 79d0a5d9da8e..f24f46776fbb 100644
> > > --- a/arch/arm/mach-mvebu/pmsu.c
> > > +++ b/arch/arm/mach-mvebu/pmsu.c
> > > @@ -685,8 +685,6 @@ static int __init armada_xp_pmsu_cpufreq_init(void)
> > >                         dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n",
> > >                                 __func__, ret);
> > >         }
> > > -
> > > -       platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
> > >         return 0;
> > >  }
> > >  
> > > diff --git a/drivers/cpufreq/cpufreq-dt-platdev.c b/drivers/cpufreq/cpufreq-dt-platdev.c
> > > index 69b2a222c84e..5704a92c52dc 100644
> > > --- a/drivers/cpufreq/cpufreq-dt-platdev.c
> > > +++ b/drivers/cpufreq/cpufreq-dt-platdev.c
> > > @@ -33,6 +33,8 @@ static const struct of_device_id machines[] = {
> > >  
> > >         { .compatible = "marvell,berlin", },
> > >  
> > > +       { .compatible = "marvell,armadaxp", },
> > > +
> > >         { .compatible = "samsung,exynos3250", },
> > >         { .compatible = "samsung,exynos4210", },
> > >         { .compatible = "samsung,exynos4212", },
> > 
> > I think to make it clear that the ordering is significant here, I would leave this
> > platform_device_register_simple() in armada_xp_pmsu_cpufreq_init().
> > 
> > However, it might be helpful to move that function into a new file in
> > drivers/cpufreq/ if that works.
> 
> We just can't get wrong with the ordering here, as this is done from
> device_initcall() and so that point is out of question.

I realize that the ordering is fixed through the way that the kernel
is linked, my worry is more about someone changing the code in some
way because it's not obvious from reading the code that the
dependency exists. If either the armada_xp_pmsu_cpufreq_init()
initcall gets changed so it does not always get called, or the
cpufreq_dt_platdev_init() initcall gets changed so it comes a little
earlier, things will break.

> The other thing that can happen is that armada_xp_pmsu_cpufreq_init()
> call can fail. In that case, most of the times cpufreq-dt ->init()
> will fail as well, so even that is fine for me.
> 
> And, so I think we can keep this patch as is.

What are the downsides of moving armada_xp_pmsu_cpufreq_init()
into drivers/cpufreq?

	Arnd

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 10/10] cpufreq: mvebu: Use generic platdev driver Viresh Kumar <viresh.kumar@linaro.org> - 2016-04-21 11:10 +0200
  Re: [PATCH 10/10] cpufreq: mvebu: Use generic platdev driver Arnd Bergmann <arnd@arndb.de> - 2016-04-23 00:50 +0200
    Re: [PATCH 10/10] cpufreq: mvebu: Use generic platdev driver Viresh Kumar <viresh.kumar@linaro.org> - 2016-04-25 05:10 +0200
      Re: [PATCH 10/10] cpufreq: mvebu: Use generic platdev driver Arnd Bergmann <arnd@arndb.de> - 2016-04-25 15:00 +0200
        Re: [PATCH 10/10] cpufreq: mvebu: Use generic platdev driver Viresh Kumar <viresh.kumar@linaro.org> - 2016-04-25 15:00 +0200
          Re: [PATCH 10/10] cpufreq: mvebu: Use generic platdev driver Arnd Bergmann <arnd@arndb.de> - 2016-04-25 17:30 +0200
            Re: [PATCH 10/10] cpufreq: mvebu: Use generic platdev driver Viresh Kumar <viresh.kumar@linaro.org> - 2016-04-25 17:30 +0200
              Re: [PATCH 10/10] cpufreq: mvebu: Use generic platdev driver Arnd Bergmann <arnd@arndb.de> - 2016-04-25 17:50 +0200
                Re: [PATCH 10/10] cpufreq: mvebu: Use generic platdev driver Thomas Petazzoni <thomas.petazzoni@free-electrons.com> - 2016-04-25 18:00 +0200

csiph-web