Its mandatory for the drivers to provide set_state_{oneshot|periodic}() (only if related modes are supported) and set_state_shutdown() callbacks today, if they are implementing the new set-state interface.
But this leads to unnecessary noop callbacks for drivers which don't want to implement them. Over that, it will lead to a full function call for nothing really useful.
Lets make all set-state callbacks optional.
Suggested-by: Daniel Lezcano daniel.lezcano@linaro.org Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- kernel/time/clockevents.c | 24 +++++++++--------------- 1 file changed, 9 insertions(+), 15 deletions(-)
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 2397b97320d8..37ba06f01818 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -120,19 +120,25 @@ static int __clockevents_switch_state(struct clock_event_device *dev, /* The clockevent device is getting replaced. Shut it down. */
case CLOCK_EVT_STATE_SHUTDOWN: - return dev->set_state_shutdown(dev); + if (dev->set_state_shutdown) + return dev->set_state_shutdown(dev); + return 0;
case CLOCK_EVT_STATE_PERIODIC: /* Core internal bug */ if (!(dev->features & CLOCK_EVT_FEAT_PERIODIC)) return -ENOSYS; - return dev->set_state_periodic(dev); + if (dev->set_state_periodic) + return dev->set_state_periodic(dev); + return 0;
case CLOCK_EVT_STATE_ONESHOT: /* Core internal bug */ if (!(dev->features & CLOCK_EVT_FEAT_ONESHOT)) return -ENOSYS; - return dev->set_state_oneshot(dev); + if (dev->set_state_oneshot) + return dev->set_state_oneshot(dev); + return 0;
case CLOCK_EVT_STATE_ONESHOT_STOPPED: /* Core internal bug */ @@ -471,18 +477,6 @@ static int clockevents_sanity_check(struct clock_event_device *dev) if (dev->features & CLOCK_EVT_FEAT_DUMMY) return 0;
- /* New state-specific callbacks */ - if (!dev->set_state_shutdown) - return -EINVAL; - - if ((dev->features & CLOCK_EVT_FEAT_PERIODIC) && - !dev->set_state_periodic) - return -EINVAL; - - if ((dev->features & CLOCK_EVT_FEAT_ONESHOT) && - !dev->set_state_oneshot) - return -EINVAL; - return 0; }