[PATCHv3 6/9] ARM: OMAP2+: timer: Add suspend-resume callbacks for clkevent device

Russ Dill russ.dill at gmail.com
Thu Aug 8 03:03:54 EDT 2013


On Tue, Aug 6, 2013 at 10:49 AM, Dave Gerlach <d-gerlach at ti.com> wrote:
> From: Vaibhav Bedia <vaibhav.bedia at ti.com>
>
> OMAP timer code registers two timers - one as clocksource
> and one as clockevent. Since AM33XX has only one usable timer
> in the WKUP domain one of the timers needs suspend-resume
> support to restore the configuration to pre-suspend state.
>
> commit adc78e6 (timekeeping: Add suspend and resume
> of clock event devices) introduced .suspend and .resume
> callbacks for clock event devices. Leverages these
> callbacks to have AM33XX clockevent timer which is
> in not in WKUP domain to behave properly across system
> suspend.
>
> Signed-off-by: Vaibhav Bedia <vaibhav.bedia at ti.com>
> Signed-off-by: Dave Gerlach <d-gerlach at ti.com>

Reviewed-by: Russ Dill <russ.dill at ti.com>

> ---
>  arch/arm/mach-omap2/timer.c |   32 ++++++++++++++++++++++++++++++++
>  1 file changed, 32 insertions(+)
>
> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> index b37e1fc..cce5d39 100644
> --- a/arch/arm/mach-omap2/timer.c
> +++ b/arch/arm/mach-omap2/timer.c
> @@ -118,11 +118,43 @@ static void omap2_gp_timer_set_mode(enum clock_event_mode mode,
>         }
>  }
>
> +static void omap_clkevt_suspend(struct clock_event_device *unused)
> +{
> +       char name[10];
> +       struct omap_hwmod *oh;
> +
> +       sprintf(name, "timer%d", clkev.id);
> +       oh = omap_hwmod_lookup(name);
> +       if (!oh)
> +               return;
> +
> +       __omap_dm_timer_stop(&clkev, 1, clkev.rate);
> +       omap_hwmod_idle(oh);
> +}
> +
> +static void omap_clkevt_resume(struct clock_event_device *unused)
> +{
> +       char name[10];
> +       struct omap_hwmod *oh;
> +
> +       sprintf(name, "timer%d", clkev.id);
> +       oh = omap_hwmod_lookup(name);
> +       if (!oh)
> +               return;
> +
> +       omap_hwmod_enable(oh);
> +       __omap_dm_timer_load_start(&clkev,
> +                       OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0, 1);
> +       __omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
> +}
> +
>  static struct clock_event_device clockevent_gpt = {
>         .features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
>         .rating         = 300,
>         .set_next_event = omap2_gp_timer_set_next_event,
>         .set_mode       = omap2_gp_timer_set_mode,
> +       .suspend        = omap_clkevt_suspend,
> +       .resume         = omap_clkevt_resume,
>  };
>
>  static struct property device_disabled = {
> --
> 1.7.9.5
>
> --
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