AT91-PIT-Remove-irq-handler-when-clock-event-is-unus.patch

From e0b1607c092a65b357c79a86405859fe3b773a20 Mon Sep 17 00:00:00 2001
From: Benedikt Spranger <b.spranger@linutronix.de>
Date: Sat, 6 Mar 2010 17:47:10 +0100
Subject: [PATCH] AT91: PIT: Remove irq handler when clock event is unused

commit b16bd4fb3290b5d380c2a67cc4c5109d65cee1d7 in tip.

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: Benedikt Spranger <b.spranger@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/arm/mach-at91/at91rm9200_time.c b/arch/arm/mach-at91/at91rm9200_time.c
index 2500f41..b546586 100644
--- a/arch/arm/mach-at91/at91rm9200_time.c
+++ b/arch/arm/mach-at91/at91rm9200_time.c
@@ -115,6 +115,7 @@ clkevt32k_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 	last_crtr = read_CRTR();
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
+		setup_irq(AT91_ID_SYS, &at91rm9200_timer_irq);
 		/* PIT for periodic irqs; fixed rate of 1/HZ */
 		irqmask = AT91_ST_PITS;
 		at91_sys_write(AT91_ST_PIMR, LATCH);
@@ -128,6 +129,7 @@ clkevt32k_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 		break;
 	case CLOCK_EVT_MODE_SHUTDOWN:
 	case CLOCK_EVT_MODE_UNUSED:
+		remove_irq(AT91_ID_SYS, &at91rm9200_timer_irq);
 	case CLOCK_EVT_MODE_RESUME:
 		irqmask = 0;
 		break;
diff --git a/arch/arm/mach-at91/at91sam926x_time.c b/arch/arm/mach-at91/at91sam926x_time.c
index 608a632..e22a06f 100644
--- a/arch/arm/mach-at91/at91sam926x_time.c
+++ b/arch/arm/mach-at91/at91sam926x_time.c
@@ -55,7 +55,7 @@ static struct clocksource pit_clk = {
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
-
+static struct irqaction at91sam926x_pit_irq;
 /*
  * Clockevent device:  interrupts every 1/HZ (== pit_cycles * MCK/16)
  */
@@ -64,6 +64,9 @@ pit_clkevt_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 {
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
+		/* Set up irq handler */
+		setup_irq(AT91_ID_SYS, &at91sam926x_pit_irq);
+
 		/* update clocksource counter */
 		pit_cnt += pit_cycle * PIT_PICNT(at91_sys_read(AT91_PIT_PIVR));
 		at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN
@@ -76,6 +79,7 @@ pit_clkevt_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 	case CLOCK_EVT_MODE_UNUSED:
 		/* disable irq, leaving the clocksource active */
 		at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN);
+		remove_irq(AT91_ID_SYS, &at91sam926x_pit_irq);
 		break;
 	case CLOCK_EVT_MODE_RESUME:
 		break;
-- 
1.7.1.1