clockevents/drivers/timer-sp804: Migrate to new 'set-state' interface
Migrate timer-sp driver to the new 'set-state' interface provided by
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.
There are few more changes worth noticing:
- The clockevent device was disabled by writing: 'TIMER_CTRL_32BIT |
TIMER_CTRL_IE' to ctrl register earlier. i.e. by un-setting the
TIMER_CTRL_ENABLE bit. Its done by writing zero now and should have
the same effect.
- For shutdown and resume we were writing the same value twice to the
register (to disable the timer), which is fixed now.
- Switching to oneshot mode was divided into two parts earlier:
- Firstly set_mode() was writing:
'TIMER_CTRL_32BIT | TIMER_CTRL_IE | TIMER_CTRL_ONESHOT'
to ctrl register (device not enabled yet)
- Then sp804_set_next_event() was enabling the device by writing
'readl(ctrl) | TIMER_CTRL_ENABLE' to the ctrl register. This was
unnecessarily complicated.
- Change this to: Stop device on set_state_oneshot and configure it in
sp804_set_next_event().
Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Olof Johansson <olof@lixom.net> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>