[PATCH 12/15] ARM: OMAP: timer: Add suspend-resume callbacks for clockevent device
Jon Hunter
jon-hunter at ti.com
Mon Nov 5 16:04:05 EST 2012
On 11/02/2012 07:32 AM, Vaibhav Bedia wrote:
> From: Vaibhav Hiremath <hvaibhav at ti.com>
>
> The current OMAP timer code registers two timers -
> one as clocksource and one as clockevent.
> AM33XX has only one usable timer in the WKUP domain
> so 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 Hiremath <hvaibhav at ti.com>
> Signed-off-by: Vaibhav Bedia <vaibhav.bedia at ti.com>
> ---
> arch/arm/mach-omap2/timer.c | 31 +++++++++++++++++++++++++++++++
> 1 files changed, 31 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> index 6584ee0..e8781fd 100644
> --- a/arch/arm/mach-omap2/timer.c
> +++ b/arch/arm/mach-omap2/timer.c
> @@ -135,6 +135,35 @@ 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", 2);
> + oh = omap_hwmod_lookup(name);
> + if (!oh)
> + return;
> +
> + 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", 2);
> + 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 = {
> .name = "gp_timer",
> .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
> @@ -142,6 +171,8 @@ static struct clock_event_device clockevent_gpt = {
> .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,
So these suspend/resume callbacks are going to be called for all OMAP2+
and AMxxxx devices? I don't think we want that. AFAIK OMAP timers will
idle on their own when stopped and don't require this.
Cheers
Jon
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