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

Santosh Shilimkar santosh.shilimkar at ti.com
Thu Aug 8 10:23:36 EDT 2013


On Tuesday 06 August 2013 01:49 PM, Dave Gerlach 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>
> ---
NAK

This patch doesn't addressed previous comments.
- The issue is specific to AM33XX and hence you
need to take care of that. These callbacks will happen on
all OMAP machines where the problem doesn't exist.

- Don't use hwmod APIs directly. At least abstract it
at omap_device layer and use that one instead.

>  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 = {
> 




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