Re: [PATCH 3/6] clocksource: bcm2835: Migrate to new 'set-state' interface

Daniel Lezcano
2015-06-11T15:25:26Z

On 06/08/2015 03:40 PM, Viresh Kumar wrote:
> Migrate bcm2835 driver to the new 'set-state' interface provided by
> the clockevents core, the earlier 'set-mode' interface is marked
> obsolete now.
>
> This also enables us to implement callbacks for new states of clockevent
> devices, for example: ONESHOT_STOPPED.

Please mention in the log you removed the RESUME because it does nothing
and the core code will just ignore it.

> Cc: Stephen Warren <swarren@wwwdotorg.org>
> Cc: Lee Jones <lee@kernel.org>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>

> ---
> drivers/clocksource/bcm2835_timer.c | 17 ++++-------------
> 1 file changed, 4 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/clocksource/bcm2835_timer.c b/drivers/clocksource/bcm2835_timer.c
> index 26ed331b1aad..b59b8e1ba503 100644
> --- a/drivers/clocksource/bcm2835_timer.c
> +++ b/drivers/clocksource/bcm2835_timer.c
> @@ -54,19 +54,9 @@ static u64 notrace bcm2835_sched_read(void)
> return readl_relaxed(system_clock);
> }
>
> -static void bcm2835_time_set_mode(enum clock_event_mode mode,
> - struct clock_event_device *evt_dev)
> +static int bcm2835_time_noop(struct clock_event_device *evt)
> {
> - switch (mode) {
> - case CLOCK_EVT_MODE_ONESHOT:
> - case CLOCK_EVT_MODE_UNUSED:
> - case CLOCK_EVT_MODE_SHUTDOWN:
> - case CLOCK_EVT_MODE_RESUME:
> - break;
> - default:
> - WARN(1, "%s: unhandled event mode %d\n", __func__, mode);
> - break;
> - }
> + return 0;
> }
>
> static int bcm2835_time_set_next_event(unsigned long event,
> @@ -129,7 +119,8 @@ static void __init bcm2835_timer_init(struct device_node *node)
> timer->evt.name = node->name;
> timer->evt.rating = 300;
> timer->evt.features = CLOCK_EVT_FEAT_ONESHOT;
> - timer->evt.set_mode = bcm2835_time_set_mode;
> + timer->evt.set_state_shutdown = bcm2835_time_noop;
> + timer->evt.set_state_oneshot = bcm2835_time_noop;

The patch is ok but there is an inconsistency on how are handled the
different callbacks. tick_resume can be omitted but not state_shutdown
and state_oneshot forcing the drivers to define empty functions.

> timer->evt.set_next_event = bcm2835_time_set_next_event;
> timer->evt.cpumask = cpumask_of(0);
> timer->act.name = node->name;

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