clocksource/drivers/exynos_mct: Clear timer interrupt when shutdown

BugLink: https://bugs.launchpad.net/bugs/1822271

commit d2f276c8 upstream.

When shutting down the timer, ensure that after we have stopped the
timer any pending interrupts are cleared. This fixes a problem when
suspending, as interrupts are disabled before the timer is stopped,
so the timer interrupt may still be asserted, preventing the system
entering a low power state when the wfi is executed.
Signed-off-by: Stuart Menefy <stuart.menefy@mathembedded.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: <stable@vger.kernel.org> # v4.3+
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Juerg Haefliger <juerg.haefliger@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/clocksource/exynos_mct.c

@@ -402,6 +402,7 @@ static int set_state_shutdown(struct clock_event_device *evt)
 
 	mevt = container_of(evt, struct mct_clock_event_device, evt);
 	exynos4_mct_tick_stop(mevt);
+	exynos4_mct_tick_clear(mevt);
 	return 0;
 }