From 1ed2053563d4d0bf70864a9df53c7a5dce7724e9 Mon Sep 17 00:00:00 2001
From: John Stultz <john.stultz@linaro.org>
Date: Fri, 22 Jul 2011 09:12:51 +0000
Subject: [PATCH] rtc: Fix RTC PIE frequency limit
commit 938f97bcf1bdd1b681d5d14d1d7117a2e22d4434 upstream.
Thomas earlier submitted a fix to limit the RTC PIE freq, but
picked 5000Hz out of the air. Willy noticed that we should
instead use the 8192Hz max from the rtc man documentation.
Cc: Willy Tarreau <w@1wt.eu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/rtc/interface.c | 2 +-
include/linux/rtc.h | 3 +++
2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index 3195dbd3ec34..eb4c88316a15 100644
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -708,7 +708,7 @@ int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq)
int err = 0;
unsigned long flags;
- if (freq <= 0 || freq > 5000)
+ if (freq <= 0 || freq > RTC_MAX_FREQ)
return -EINVAL;
retry:
spin_lock_irqsave(&rtc->irq_task_lock, flags);
diff --git a/include/linux/rtc.h b/include/linux/rtc.h
index b27ebea25660..93f4d035076b 100644
--- a/include/linux/rtc.h
+++ b/include/linux/rtc.h
@@ -97,6 +97,9 @@ struct rtc_pll_info {
#define RTC_AF 0x20 /* Alarm interrupt */
#define RTC_UF 0x10 /* Update interrupt for 1Hz RTC */
+
+#define RTC_MAX_FREQ 8192
+
#ifdef __KERNEL__
#include <linux/types.h>
--
2.34.1