Setup and remove the interrupt handler in clock event mode selection.
This avoids calling the (shared) interrupt handler when the device is not
used.
Signed-off-by: Alexandre Belloni <alexandre.bell...@free-electrons.com>
---
drivers/clocksource/timer-atmel-st.c | 43 +++++++++++++++++++++++++++++-------
1 file changed, 35 insertions(+), 8 deletions(-)
diff --git a/drivers/clocksource/timer-atmel-st.c
b/drivers/clocksource/timer-atmel-st.c
index 41b7b6dc1d0d..a498b7446006 100644
--- a/drivers/clocksource/timer-atmel-st.c
+++ b/drivers/clocksource/timer-atmel-st.c
@@ -31,6 +31,7 @@
static unsigned long last_crtr;
static u32 irqmask;
+static int irq;
static struct clock_event_device clkevt;
static struct regmap *regmap_st;
@@ -121,17 +122,45 @@ static int clkevt32k_shutdown(struct clock_event_device
*evt)
clkdev32k_disable_and_flush_irq();
irqmask = 0;
regmap_write(regmap_st, AT91_ST_IER, irqmask);
+
+ if (clockevent_state_periodic(evt) || clockevent_state_oneshot(evt))
+ free_irq(irq, regmap_st);
+
+ return 0;
+}
+
+static int atmel_st_request_irq(struct clock_event_device *dev)
+{
+ int ret;
+
+ if (clockevent_state_periodic(dev) || clockevent_state_oneshot(dev))
+ return 0;
+
+ ret = request_irq(irq, at91rm9200_timer_interrupt,
+ IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+ "at91_tick", regmap_st);
+ if (ret) {
+ pr_alert("Unable to setup IRQ\n");
+ return ret;
+ }
+
return 0;
}
static int clkevt32k_set_oneshot(struct clock_event_device *dev)
{
+ int ret;
+
clkdev32k_disable_and_flush_irq();
/*
* ALM for oneshot irqs, set by next_event()
* before 32 seconds have passed.
*/
+ ret = atmel_st_request_irq(dev);
+ if (ret)
+ return ret;
+
irqmask = AT91_ST_ALMS;
regmap_write(regmap_st, AT91_ST_RTAR, last_crtr);
regmap_write(regmap_st, AT91_ST_IER, irqmask);
@@ -140,9 +169,15 @@ static int clkevt32k_set_oneshot(struct clock_event_device
*dev)
static int clkevt32k_set_periodic(struct clock_event_device *dev)
{
+ int ret;
+
clkdev32k_disable_and_flush_irq();
/* PIT for periodic irqs; fixed rate of 1/HZ */
+ ret = atmel_st_request_irq(dev);
+ if (ret)
+ return ret;
+
irqmask = AT91_ST_PITS;
regmap_write(regmap_st, AT91_ST_PIMR, RM9200_TIMER_LATCH);
regmap_write(regmap_st, AT91_ST_IER, irqmask);
@@ -198,7 +233,6 @@ static struct clock_event_device clkevt = {
static void __init atmel_st_timer_init(struct device_node *node)
{
unsigned int val;
- int irq, ret;
regmap_st = syscon_node_to_regmap(node);
if (IS_ERR(regmap_st))
@@ -214,13 +248,6 @@ static void __init atmel_st_timer_init(struct device_node
*node)
if (!irq)
panic(pr_fmt("Unable to get IRQ from DT\n"));
- /* Make IRQs happen for the system timer */
- ret = request_irq(irq, at91rm9200_timer_interrupt,
- IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
- "at91_tick", regmap_st);
- if (ret)
- panic(pr_fmt("Unable to setup IRQ\n"));
-
/* The 32KiHz "Slow Clock" (tick every 30517.58 nanoseconds) is used
* directly for the clocksource and all clockevents, after adjusting
* its prescaler from the 1 Hz default.
--
2.1.4
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