[PATCH v2 4/4] clocksource: timer-atmel-pit: simplify IRQ handler

From: Alexandre Belloni
Date: Mon Aug 08 2016 - 09:34:07 EST


Because the PIT is also a proper clocksource, the timekeeping code is
already able to handle lost ticks.

Reported-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
---
drivers/clocksource/timer-atmel-pit.c | 11 +++--------
1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/clocksource/timer-atmel-pit.c b/drivers/clocksource/timer-atmel-pit.c
index af657fdce665..c5f3291328bd 100644
--- a/drivers/clocksource/timer-atmel-pit.c
+++ b/drivers/clocksource/timer-atmel-pit.c
@@ -152,15 +152,10 @@ static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id)
/* The PIT interrupt may be disabled, and is shared */
if (clockevent_state_periodic(&data->clkevt) &&
(pit_read(data->base, AT91_PIT_SR) & AT91_PIT_PITS)) {
- unsigned nr_ticks;
-
/* Get number of ticks performed before irq, and ack it */
- nr_ticks = PIT_PICNT(pit_read(data->base, AT91_PIT_PIVR));
- do {
- data->cnt += data->cycle;
- data->clkevt.event_handler(&data->clkevt);
- nr_ticks--;
- } while (nr_ticks);
+ data->cnt += data->cycle * PIT_PICNT(pit_read(data->base,
+ AT91_PIT_PIVR));
+ data->clkevt.event_handler(&data->clkevt);

return IRQ_HANDLED;
}
--
2.8.1