linux-kernel - [PATCH] rtc: rtc-s3c: fix no occurrence of alarm interrupt

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 31 Aug 2011 19:21:50 +0900
From:	Donggeun Kim <dg77.kim@...sung.com>
To:	rtc-linux@...glegroups.com
Cc:	a.zummo@...ertech.it, linux-kernel@...r.kernel.org,
	myungjoo.ham@...sung.com, kyungmin.park@...sung.com,
	dg77.kim@...sung.com
Subject: [PATCH] rtc: rtc-s3c: fix no occurrence of alarm interrupt

The driver does not generate alarm interrupt
even though time for alarm is set.
This results from disabling rtc_clk after setting time for alarm.
To generate alarm interrupt,
the driver should maintain enabled state for rtc_clk
until alarm interrupt occurs.
This patch allows to generate alarm interrupt.

Signed-off-by: Donggeun Kim <dg77.kim@...sung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@...sung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@...sung.com>
---
 drivers/rtc/rtc-s3c.c |   26 ++++++++++++++++++++++++++
 1 files changed, 26 insertions(+), 0 deletions(-)

diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
index 4e7c04e..b68697e 100644
--- a/drivers/rtc/rtc-s3c.c
+++ b/drivers/rtc/rtc-s3c.c
@@ -50,6 +50,27 @@ static bool wake_en;
 static enum s3c_cpu_type s3c_rtc_cpu_type;
 
 static DEFINE_SPINLOCK(s3c_rtc_pie_lock);
+static DEFINE_SPINLOCK(s3c_rtc_alarm_clk_lock);
+
+static void s3c_rtc_alarm_clk_enable(bool enable)
+{
+	static bool alarm_clk_enabled;
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&s3c_rtc_alarm_clk_lock, irq_flags);
+	if (enable) {
+		if (!alarm_clk_enabled) {
+			clk_enable(rtc_clk);
+			alarm_clk_enabled = true;
+		}
+	} else {
+		if (alarm_clk_enabled) {
+			clk_disable(rtc_clk);
+			alarm_clk_enabled = false;
+		}
+	}
+	spin_unlock_irqrestore(&s3c_rtc_alarm_clk_lock, irq_flags);
+}
 
 /* IRQ Handlers */
 
@@ -64,6 +85,9 @@ static irqreturn_t s3c_rtc_alarmirq(int irq, void *id)
 		writeb(S3C2410_INTP_ALM, s3c_rtc_base + S3C2410_INTP);
 
 	clk_disable(rtc_clk);
+
+	s3c_rtc_alarm_clk_enable(false);
+
 	return IRQ_HANDLED;
 }
 
@@ -97,6 +121,8 @@ static int s3c_rtc_setaie(struct device *dev, unsigned int enabled)
 	writeb(tmp, s3c_rtc_base + S3C2410_RTCALM);
 	clk_disable(rtc_clk);
 
+	s3c_rtc_alarm_clk_enable(enabled);
+
 	return 0;
 }
 
-- 
1.7.4.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/