From a8a6b0b1d9b4c35f69f5ab872c2fb8ea5a296c1e Mon Sep 17 00:00:00 2001
From: Clemens Ladisch <clemens@ladisch.de>
Date: Tue, 26 Oct 2010 14:22:13 -0700
Subject: [PATCH] --- yaml --- r: 217499 b: refs/heads/master c:
 96e9694df446d1154ec2f4fdba8908588b9cba38 h: refs/heads/master i:   217497:
 57ee5d3dc3e3ccecba6d17f88e0192717ee7d203   217495:
 f947b61caed58424ed1a16c5b9d5bef86963be83 v: v3

---
 [refs]                    |  2 +-
 trunk/drivers/char/hpet.c | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 010c1475a8e5..e87625a1a00a 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a56d5318716d120e040294bb258901ba89fb9c90
+refs/heads/master: 96e9694df446d1154ec2f4fdba8908588b9cba38
diff --git a/trunk/drivers/char/hpet.c b/trunk/drivers/char/hpet.c
index 84e6a7e673b7..a2cbb828e92a 100644
--- a/trunk/drivers/char/hpet.c
+++ b/trunk/drivers/char/hpet.c
@@ -465,6 +465,21 @@ static int hpet_ioctl_ieon(struct hpet_dev *devp)
 	if (irq) {
 		unsigned long irq_flags;
 
+		if (devp->hd_flags & HPET_SHARED_IRQ) {
+			/*
+			 * To prevent the interrupt handler from seeing an
+			 * unwanted interrupt status bit, program the timer
+			 * so that it will not fire in the near future ...
+			 */
+			writel(readl(&timer->hpet_config) & ~Tn_TYPE_CNF_MASK,
+			       &timer->hpet_config);
+			write_counter(read_counter(&hpet->hpet_mc),
+				      &timer->hpet_compare);
+			/* ... and clear any left-over status. */
+			isr = 1 << (devp - devp->hd_hpets->hp_dev);
+			writel(isr, &hpet->hpet_isr);
+		}
+
 		sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
 		irq_flags = devp->hd_flags & HPET_SHARED_IRQ
 						? IRQF_SHARED : IRQF_DISABLED;