Subject: [PATCH 02/11] ARM: OMAP3: clock: add API to enable/disable autoidle for a single clock

From: [email-masked] (Mike Turquette)
Date: Mon, 21 Oct 2013 05:26:10 -0700

Quoting Paul Walmsley (2013-10-19 10:16:50)
> On Fri, 11 Oct 2013, Tero Kristo wrote:
> 
> > Some drivers require direct access to the autoidle functionality of the
> > interface clocks. Added clock APIs for these, so that the drivers do not
> > need to access CM registers directly.
> > 
> > Signed-off-by: Tero Kristo <[email-masked]>
> 
> Thanks, queued.  Please coordinate with Mike to get 
> allow_idle/deny_idle-type interfaces into the Common Clock Framework, so 
> these can be replaced with standard CCF-type allow_idle() & deny_idle() 
> functions.  That interface should include use-counting so multiple callers 
> can use allow_idle() and deny_idle() without stomping on each other.

Where and when are these functions called? IIRC these are only accessed
at boot/init time, though I may be wrong. If they are a boot-time thing
then the .init callback provided in struct clk may be sufficient.

Regards,
Mike

> 
> 
> - Paul
> 
> > ---
> >  arch/arm/mach-omap2/clock.c |   38 ++++++++++++++++++++++++++++++++++++++
> >  arch/arm/mach-omap2/clock.h |    2 ++
> >  2 files changed, 40 insertions(+)
> > 
> > diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c
> > index 0c38ca9..c7c5d31 100644
> > --- a/arch/arm/mach-omap2/clock.c
> > +++ b/arch/arm/mach-omap2/clock.c
> > @@ -543,6 +543,44 @@ int omap2_clk_disable_autoidle_all(void)
> >  }
> >  
> >  /**
> > + * omap2_clk_deny_idle - disable autoidle on an OMAP clock
> > + * @clk: struct clk * to disable autoidle for
> > + *
> > + * Disable autoidle on an OMAP clock.
> > + */
> > +int omap2_clk_deny_idle(struct clk *clk)
> > +{
> > +     struct clk_hw_omap *c;
> > +
> > +     if (__clk_get_flags(clk) & CLK_IS_BASIC)
> > +             return -EINVAL;
> > +
> > +     c = to_clk_hw_omap(__clk_get_hw(clk));
> > +     if (c->ops && c->ops->deny_idle)
> > +             c->ops->deny_idle(c);
> > +     return 0;
> > +}
> > +
> > +/**
> > + * omap2_clk_allow_idle - enable autoidle on an OMAP clock
> > + * @clk: struct clk * to enable autoidle for
> > + *
> > + * Enable autoidle on an OMAP clock.
> > + */
> > +int omap2_clk_allow_idle(struct clk *clk)
> > +{
> > +     struct clk_hw_omap *c;
> > +
> > +     if (__clk_get_flags(clk) & CLK_IS_BASIC)
> > +             return -EINVAL;
> > +
> > +     c = to_clk_hw_omap(__clk_get_hw(clk));
> > +     if (c->ops && c->ops->allow_idle)
> > +             c->ops->allow_idle(c);
> > +     return 0;
> > +}
> > +
> > +/**
> >   * omap2_clk_enable_init_clocks - prepare & enable a list of clocks
> >   * @clk_names: ptr to an array of strings of clock names to enable
> >   * @num_clocks: number of clock names in @clk_names
> > diff --git a/arch/arm/mach-omap2/clock.h b/arch/arm/mach-omap2/clock.h
> > index 7aa32cd..82916cc 100644
> > --- a/arch/arm/mach-omap2/clock.h
> > +++ b/arch/arm/mach-omap2/clock.h
> > @@ -411,6 +411,8 @@ void omap2_clk_dflt_find_idlest(struct clk_hw_omap *clk,
> >  void omap2_init_clk_hw_omap_clocks(struct clk *clk);
> >  int omap2_clk_enable_autoidle_all(void);
> >  int omap2_clk_disable_autoidle_all(void);
> > +int omap2_clk_allow_idle(struct clk *clk);
> > +int omap2_clk_deny_idle(struct clk *clk);
> >  void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks);
> >  int omap2_clk_switch_mpurate_at_boot(const char *mpurate_ck_name);
> >  void omap2_clk_print_new_rates(const char *hfclkin_ck_name,
> > -- 
> > 1.7.9.5
> > 
> 
> 
> - Paul