clockevents: fix resume logic

We need to make sure, that the clockevent devices are resumed, before
the tick is resumed. The current resume logic does not guarantee this.

Add CLOCK_EVT_MODE_RESUME and call the set mode functions of the clock
event devices before resuming the tick / oneshot functionality.

Fixup the existing users.

Thanks to Nigel Cunningham for tracking down a long standing thinko,
which affected the jinxed VAIO.

[akpm@linux-foundation.org: xen build fix]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

16 files changed, 51 insertions, 88 deletions

diff --git a/arch/arm/mach-davinci/time.c b/arch/arm/mach-davinci/time.c
index 4d8425de6922..e96a3dcdc1a7 100644
--- a/arch/arm/mach-davinci/time.c
+++ b/arch/arm/mach-davinci/time.c
@@ -285,6 +285,8 @@ static void davinci_set_mode(enum clock_event_mode mode,
         case CLOCK_EVT_MODE_SHUTDOWN:
                 t->opts = TIMER_OPTS_DISABLED;
                 break;
+        case CLOCK_EVT_MODE_RESUME:
+                break;
         }
 }
 
diff --git a/arch/arm/mach-imx/time.c b/arch/arm/mach-imx/time.c
index 010f6fa984a6..d86d124aea22 100644
--- a/arch/arm/mach-imx/time.c
+++ b/arch/arm/mach-imx/time.c
@@ -159,6 +159,7 @@ static void imx_set_mode(enum clock_event_mode mode, struct clock_event_device *
                 break;
         case CLOCK_EVT_MODE_SHUTDOWN:
         case CLOCK_EVT_MODE_UNUSED:
+        case CLOCK_EVT_MODE_RESUME:
                 /* Left event sources disabled, no more interrupts appears */
                 break;
         }
diff --git a/arch/arm/mach-ixp4xx/common.c b/arch/arm/mach-ixp4xx/common.c
index 8112f726ffa0..23e7fba6d3e1 100644
--- a/arch/arm/mach-ixp4xx/common.c
+++ b/arch/arm/mach-ixp4xx/common.c
@@ -459,6 +459,8 @@ static void ixp4xx_set_mode(enum clock_event_mode mode,
         default:
                 osrt = opts = 0;
                 break;
+        case CLOCK_EVT_MODE_RESUME:
+                break;
         }
 
         *IXP4XX_OSRT1 = osrt | opts;
diff --git a/arch/arm/mach-omap1/time.c b/arch/arm/mach-omap1/time.c
index 3705d20c4e5c..237651ebae5d 100644
--- a/arch/arm/mach-omap1/time.c
+++ b/arch/arm/mach-omap1/time.c
@@ -156,6 +156,7 @@ static void omap_mpu_set_mode(enum clock_event_mode mode,
                 break;
         case CLOCK_EVT_MODE_UNUSED:
         case CLOCK_EVT_MODE_SHUTDOWN:
+        case CLOCK_EVT_MODE_RESUME:
                 break;
         }
 }
diff --git a/arch/arm/plat-omap/timer32k.c b/arch/arm/plat-omap/timer32k.c
index 2feceec8eccd..b0af014b0e2c 100644
--- a/arch/arm/plat-omap/timer32k.c
+++ b/arch/arm/plat-omap/timer32k.c
@@ -156,6 +156,8 @@ static void omap_32k_timer_set_mode(enum clock_event_mode mode,
         case CLOCK_EVT_MODE_SHUTDOWN:
                 omap_32k_timer_stop();
                 break;
+        case CLOCK_EVT_MODE_RESUME:
+                break;
         }
 }
 
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index 67824f3bb974..610f44b24367 100644
--- a/arch/i386/kernel/apic.c
+++ b/arch/i386/kernel/apic.c
@@ -263,6 +263,9 @@ static void lapic_timer_setup(enum clock_event_mode mode,
                 v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
                 apic_write_around(APIC_LVTT, v);
                 break;
+        case CLOCK_EVT_MODE_RESUME:
+                /* Nothing to do here */
+                break;
         }
 
         local_irq_restore(flags);
diff --git a/arch/i386/kernel/hpet.c b/arch/i386/kernel/hpet.c
index 17d73459fc5f..cfbf792a0bf4 100644
--- a/arch/i386/kernel/hpet.c
+++ b/arch/i386/kernel/hpet.c
@@ -187,6 +187,10 @@ static void hpet_set_mode(enum clock_event_mode mode,
                 cfg &= ~HPET_TN_ENABLE;
                 hpet_writel(cfg, HPET_T0_CFG);
                 break;
+
+        case CLOCK_EVT_MODE_RESUME:
+                hpet_enable_int();
+                break;
         }
 }
 
@@ -217,6 +221,7 @@ static struct clocksource clocksource_hpet = {
         .mask           = HPET_MASK,
         .shift          = HPET_SHIFT,
         .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
+        .resume         = hpet_start_counter,
 };
 
 /*
@@ -291,7 +296,6 @@ int __init hpet_enable(void)
 
         clocksource_register(&clocksource_hpet);
 
-
         if (id & HPET_ID_LEGSUP) {
                 hpet_enable_int();
                 hpet_reserve_platform_timers(id);
@@ -524,68 +528,3 @@ irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id)
         return IRQ_HANDLED;
 }
 #endif
-
-
-/*
- * Suspend/resume part
- */
-
-#ifdef CONFIG_PM
-
-static int hpet_suspend(struct sys_device *sys_device, pm_message_t state)
-{
-        unsigned long cfg = hpet_readl(HPET_CFG);
-
-        cfg &= ~(HPET_CFG_ENABLE|HPET_CFG_LEGACY);
-        hpet_writel(cfg, HPET_CFG);
-
-        return 0;
-}
-
-static int hpet_resume(struct sys_device *sys_device)
-{
-        unsigned int id;
-
-        hpet_start_counter();
-
-        id = hpet_readl(HPET_ID);
-
-        if (id & HPET_ID_LEGSUP)
-                hpet_enable_int();
-
-        return 0;
-}
-
-static struct sysdev_class hpet_class = {
-        set_kset_name("hpet"),
-        .suspend        = hpet_suspend,
-        .resume         = hpet_resume,
-};
-
-static struct sys_device hpet_device = {
-        .id             = 0,
-        .cls            = &hpet_class,
-};
-
-
-static __init int hpet_register_sysfs(void)
-{
-        int err;
-
-        if (!is_hpet_capable())
-                return 0;
-
-        err = sysdev_class_register(&hpet_class);
-
-        if (!err) {
-                err = sysdev_register(&hpet_device);
-                if (err)
-                        sysdev_class_unregister(&hpet_class);
-        }
-
-        return err;
-}
-
-device_initcall(hpet_register_sysfs);
-
-#endif
diff --git a/arch/i386/kernel/i8253.c b/arch/i386/kernel/i8253.c
index f8a3c4054c70..931eabe1e560 100644
--- a/arch/i386/kernel/i8253.c
+++ b/arch/i386/kernel/i8253.c
@@ -3,11 +3,11 @@
  *
  */
 #include <linux/clockchips.h>
-#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
 #include <linux/jiffies.h>
-#include <linux/sysdev.h>
 #include <linux/module.h>
-#include <linux/init.h>
+#include <linux/spinlock.h>
 
 #include <asm/smp.h>
 #include <asm/delay.h>
@@ -41,26 +41,24 @@ static void init_pit_timer(enum clock_event_mode mode,
         case CLOCK_EVT_MODE_PERIODIC:
                 /* binary, mode 2, LSB/MSB, ch 0 */
                 outb_p(0x34, PIT_MODE);
-                udelay(10);
                 outb_p(LATCH & 0xff , PIT_CH0); /* LSB */
-                udelay(10);
                 outb(LATCH >> 8 , PIT_CH0);     /* MSB */
                 break;
 
-        /*
-         * Avoid unnecessary state transitions, as it confuses
-         * Geode / Cyrix based boxen.
-         */
         case CLOCK_EVT_MODE_SHUTDOWN:
-                if (evt->mode == CLOCK_EVT_MODE_UNUSED)
-                        break;
         case CLOCK_EVT_MODE_UNUSED:
-                if (evt->mode == CLOCK_EVT_MODE_SHUTDOWN)
-                        break;
+                outb_p(0x30, PIT_MODE);
+                outb_p(0, PIT_CH0);     /* LSB */
+                outb_p(0, PIT_CH0);     /* MSB */
+                break;
+
         case CLOCK_EVT_MODE_ONESHOT:
                 /* One shot setup */
                 outb_p(0x38, PIT_MODE);
-                udelay(10);
+                break;
+
+        case CLOCK_EVT_MODE_RESUME:
+                /* Nothing to do here */
                 break;
         }
         spin_unlock_irqrestore(&i8253_lock, flags);
diff --git a/arch/i386/kernel/vmiclock.c b/arch/i386/kernel/vmiclock.c
index f9b845f4e692..d23077cca45b 100644
--- a/arch/i386/kernel/vmiclock.c
+++ b/arch/i386/kernel/vmiclock.c
@@ -142,6 +142,7 @@ static void vmi_timer_set_mode(enum clock_event_mode mode,
 
         switch (mode) {
         case CLOCK_EVT_MODE_ONESHOT:
+        case CLOCK_EVT_MODE_RESUME:
                 break;
         case CLOCK_EVT_MODE_PERIODIC:
                 cycles_per_hz = vmi_timer_ops.get_cycle_frequency();
diff --git a/arch/i386/xen/time.c b/arch/i386/xen/time.c
index 51fdabf1fd4d..dfd6db69ead5 100644
--- a/arch/i386/xen/time.c
+++ b/arch/i386/xen/time.c
@@ -412,6 +412,7 @@ static void xen_timerop_set_mode(enum clock_event_mode mode,
                 break;
 
         case CLOCK_EVT_MODE_ONESHOT:
+        case CLOCK_EVT_MODE_RESUME:
                 break;
 
         case CLOCK_EVT_MODE_UNUSED:
@@ -474,6 +475,8 @@ static void xen_vcpuop_set_mode(enum clock_event_mode mode,
                     HYPERVISOR_vcpu_op(VCPUOP_stop_periodic_timer, cpu, NULL))
                         BUG();
                 break;
+        case CLOCK_EVT_MODE_RESUME:
+                break;
         }
 }
 
diff --git a/arch/sh/kernel/timers/timer-tmu.c b/arch/sh/kernel/timers/timer-tmu.c
index 097ebd49f1bf..7aca37d79766 100644
--- a/arch/sh/kernel/timers/timer-tmu.c
+++ b/arch/sh/kernel/timers/timer-tmu.c
@@ -80,6 +80,7 @@ static void tmu_set_mode(enum clock_event_mode mode,
                 break;
         case CLOCK_EVT_MODE_UNUSED:
         case CLOCK_EVT_MODE_SHUTDOWN:
+        case CLOCK_EVT_MODE_RESUME:
                 break;
         }
 }
diff --git a/arch/sparc64/kernel/time.c b/arch/sparc64/kernel/time.c
index e340eb401fb9..87c10a7544da 100644
--- a/arch/sparc64/kernel/time.c
+++ b/arch/sparc64/kernel/time.c
@@ -931,6 +931,7 @@ static void sparc64_timer_setup(enum clock_event_mode mode,
 {
         switch (mode) {
         case CLOCK_EVT_MODE_ONESHOT:
+        case CLOCK_EVT_MODE_RESUME:
                 break;
 
         case CLOCK_EVT_MODE_SHUTDOWN:
diff --git a/drivers/lguest/lguest.c b/drivers/lguest/lguest.c
index 434fea1e82f7..18dade06d4a9 100644
--- a/drivers/lguest/lguest.c
+++ b/drivers/lguest/lguest.c
@@ -398,6 +398,8 @@ static void lguest_clockevent_set_mode(enum clock_event_mode mode,
                 break;
         case CLOCK_EVT_MODE_PERIODIC:
                 BUG();
+        case CLOCK_EVT_MODE_RESUME:
+                break;
         }
 }
 
diff --git a/include/linux/clockchips.h b/include/linux/clockchips.h
index 8d7a39019ace..e0bd46eb2414 100644
--- a/include/linux/clockchips.h
+++ b/include/linux/clockchips.h
@@ -23,6 +23,7 @@ enum clock_event_mode {
         CLOCK_EVT_MODE_SHUTDOWN,
         CLOCK_EVT_MODE_PERIODIC,
         CLOCK_EVT_MODE_ONESHOT,
+        CLOCK_EVT_MODE_RESUME,
 };
 
 /* Clock event notification values */
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 8001d37071f5..8339af229cb9 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -49,7 +49,7 @@ cpumask_t *tick_get_broadcast_mask(void)
  */
 static void tick_broadcast_start_periodic(struct clock_event_device *bc)
 {
-        if (bc && bc->mode == CLOCK_EVT_MODE_SHUTDOWN)
+        if (bc)
                 tick_setup_periodic(bc, 1);
 }
 
@@ -299,7 +299,7 @@ void tick_suspend_broadcast(void)
         spin_lock_irqsave(&tick_broadcast_lock, flags);
 
         bc = tick_broadcast_device.evtdev;
-        if (bc && tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
+        if (bc)
                 clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN);
 
         spin_unlock_irqrestore(&tick_broadcast_lock, flags);
@@ -316,6 +316,8 @@ int tick_resume_broadcast(void)
         bc = tick_broadcast_device.evtdev;
 
         if (bc) {
+                clockevents_set_mode(bc, CLOCK_EVT_MODE_RESUME);
+
                 switch (tick_broadcast_device.mode) {
                 case TICKDEV_MODE_PERIODIC:
                         if(!cpus_empty(tick_broadcast_mask))
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index a96ec9ab3454..77a21abc8716 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -318,12 +318,17 @@ static void tick_resume(void)
 {
         struct tick_device *td = &__get_cpu_var(tick_cpu_device);
         unsigned long flags;
+        int broadcast = tick_resume_broadcast();
 
         spin_lock_irqsave(&tick_device_lock, flags);
-        if (td->mode == TICKDEV_MODE_PERIODIC)
-                tick_setup_periodic(td->evtdev, 0);
-        else
-                tick_resume_oneshot();
+        clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_RESUME);
+
+        if (!broadcast) {
+                if (td->mode == TICKDEV_MODE_PERIODIC)
+                        tick_setup_periodic(td->evtdev, 0);
+                else
+                        tick_resume_oneshot();
+        }
         spin_unlock_irqrestore(&tick_device_lock, flags);
 }
 
@@ -360,8 +365,7 @@ static int tick_notify(struct notifier_block *nb, unsigned long reason,
                 break;
 
         case CLOCK_EVT_NOTIFY_RESUME:
-                if (!tick_resume_broadcast())
-                        tick_resume();
+                tick_resume();
                 break;
 
         default: