clockevents/drivers/atmel-st: Migrate to new 'set-state' interface

Migrate atmel-st 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.

Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Tested-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

drivers/clocksource/timer-atmel-st.c

@@ -106,36 +106,47 @@ static struct clocksource clk32k = {
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
-static void
-clkevt32k_mode(enum clock_event_mode mode, struct clock_event_device *dev)
+static void clkdev32k_disable_and_flush_irq(void)
 {
 	unsigned int val;
 
 	/* Disable and flush pending timer interrupts */
 	regmap_write(regmap_st, AT91_ST_IDR, AT91_ST_PITS | AT91_ST_ALMS);
 	regmap_read(regmap_st, AT91_ST_SR, &val);
-
 	last_crtr = read_CRTR();
-	switch (mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-		/* PIT for periodic irqs; fixed rate of 1/HZ */
-		irqmask = AT91_ST_PITS;
-		regmap_write(regmap_st, AT91_ST_PIMR, RM9200_TIMER_LATCH);
-		break;
-	case CLOCK_EVT_MODE_ONESHOT:
-		/* ALM for oneshot irqs, set by next_event()
-		 * before 32 seconds have passed
-		 */
-		irqmask = AT91_ST_ALMS;
-		regmap_write(regmap_st, AT91_ST_RTAR, last_crtr);
-		break;
-	case CLOCK_EVT_MODE_SHUTDOWN:
-	case CLOCK_EVT_MODE_UNUSED:
-	case CLOCK_EVT_MODE_RESUME:
-		irqmask = 0;
-		break;
-	}
+}
+
+static int clkevt32k_shutdown(struct clock_event_device *evt)
+{
+	clkdev32k_disable_and_flush_irq();
+	irqmask = 0;
+	regmap_write(regmap_st, AT91_ST_IER, irqmask);
+	return 0;
+}
+
+static int clkevt32k_set_oneshot(struct clock_event_device *dev)
+{
+	clkdev32k_disable_and_flush_irq();
+
+	/*
+	 * ALM for oneshot irqs, set by next_event()
+	 * before 32 seconds have passed.
+	 */
+	irqmask = AT91_ST_ALMS;
+	regmap_write(regmap_st, AT91_ST_RTAR, last_crtr);
 	regmap_write(regmap_st, AT91_ST_IER, irqmask);
+	return 0;
+}
+
+static int clkevt32k_set_periodic(struct clock_event_device *dev)
+{
+	clkdev32k_disable_and_flush_irq();
+
+	/* PIT for periodic irqs; fixed rate of 1/HZ */
+	irqmask = AT91_ST_PITS;
+	regmap_write(regmap_st, AT91_ST_PIMR, RM9200_TIMER_LATCH);
+	regmap_write(regmap_st, AT91_ST_IER, irqmask);
+	return 0;
 }
 
 static int
@@ -170,11 +181,15 @@ clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev)
 }
 
 static struct clock_event_device clkevt = {
-	.name		= "at91_tick",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.rating		= 150,
-	.set_next_event	= clkevt32k_next_event,
-	.set_mode	= clkevt32k_mode,
+	.name			= "at91_tick",
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.rating			= 150,
+	.set_next_event		= clkevt32k_next_event,
+	.set_state_shutdown	= clkevt32k_shutdown,
+	.set_state_periodic	= clkevt32k_set_periodic,
+	.set_state_oneshot	= clkevt32k_set_oneshot,
+	.tick_resume		= clkevt32k_shutdown,
 };
 
 /*