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authorThomas Gleixner <tglx@linutronix.de>2013-02-04 11:03:03 +0100
committerThomas Gleixner <tglx@linutronix.de>2013-02-04 11:03:03 +0100
commit90889a635a9b5488624bccce3ff6b2eec68c007b (patch)
tree8ddde1e04060bd65ca2aafb09b38066cb7d69b4d /drivers/rtc
parentMerge branch 'timers/for-arm' into timers/core (diff)
parenttimekeeping: Switch HAS_PERSISTENT_CLOCK to ALWAYS_USE_PERSISTENT_CLOCK (diff)
downloadlinux-90889a635a9b5488624bccce3ff6b2eec68c007b.tar.xz
linux-90889a635a9b5488624bccce3ff6b2eec68c007b.zip
Merge branch 'fortglx/3.9/time' of git://git.linaro.org/people/jstultz/linux into timers/core
Trivial conflict in arch/x86/Kconfig Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'drivers/rtc')
-rw-r--r--drivers/rtc/Kconfig12
-rw-r--r--drivers/rtc/Makefile1
-rw-r--r--drivers/rtc/class.c7
-rw-r--r--drivers/rtc/systohc.c44
4 files changed, 63 insertions, 1 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 923a9da9c829..5e44eaabf457 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -20,14 +20,24 @@ if RTC_CLASS
config RTC_HCTOSYS
bool "Set system time from RTC on startup and resume"
default y
+ depends on !ALWAYS_USE_PERSISTENT_CLOCK
help
If you say yes here, the system time (wall clock) will be set using
the value read from a specified RTC device. This is useful to avoid
unnecessary fsck runs at boot time, and to network better.
+config RTC_SYSTOHC
+ bool "Set the RTC time based on NTP synchronization"
+ default y
+ depends on !ALWAYS_USE_PERSISTENT_CLOCK
+ help
+ If you say yes here, the system time (wall clock) will be stored
+ in the RTC specified by RTC_HCTOSYS_DEVICE approximately every 11
+ minutes if userspace reports synchronized NTP status.
+
config RTC_HCTOSYS_DEVICE
string "RTC used to set the system time"
- depends on RTC_HCTOSYS = y
+ depends on RTC_HCTOSYS = y || RTC_SYSTOHC = y
default "rtc0"
help
The RTC device that will be used to (re)initialize the system
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 4418ef3f9ecc..ec2988b00a44 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -6,6 +6,7 @@ ccflags-$(CONFIG_RTC_DEBUG) := -DDEBUG
obj-$(CONFIG_RTC_LIB) += rtc-lib.o
obj-$(CONFIG_RTC_HCTOSYS) += hctosys.o
+obj-$(CONFIG_RTC_SYSTOHC) += systohc.o
obj-$(CONFIG_RTC_CLASS) += rtc-core.o
rtc-core-y := class.o interface.o
diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index 5143629dedbd..26388f182594 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -50,6 +50,10 @@ static int rtc_suspend(struct device *dev, pm_message_t mesg)
struct rtc_device *rtc = to_rtc_device(dev);
struct rtc_time tm;
struct timespec delta, delta_delta;
+
+ if (has_persistent_clock())
+ return 0;
+
if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
return 0;
@@ -88,6 +92,9 @@ static int rtc_resume(struct device *dev)
struct timespec new_system, new_rtc;
struct timespec sleep_time;
+ if (has_persistent_clock())
+ return 0;
+
rtc_hctosys_ret = -ENODEV;
if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
return 0;
diff --git a/drivers/rtc/systohc.c b/drivers/rtc/systohc.c
new file mode 100644
index 000000000000..bf3e242ccc5c
--- /dev/null
+++ b/drivers/rtc/systohc.c
@@ -0,0 +1,44 @@
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ */
+#include <linux/rtc.h>
+#include <linux/time.h>
+
+/**
+ * rtc_set_ntp_time - Save NTP synchronized time to the RTC
+ * @now: Current time of day
+ *
+ * Replacement for the NTP platform function update_persistent_clock
+ * that stores time for later retrieval by rtc_hctosys.
+ *
+ * Returns 0 on successful RTC update, -ENODEV if a RTC update is not
+ * possible at all, and various other -errno for specific temporary failure
+ * cases.
+ *
+ * If temporary failure is indicated the caller should try again 'soon'
+ */
+int rtc_set_ntp_time(struct timespec now)
+{
+ struct rtc_device *rtc;
+ struct rtc_time tm;
+ int err = -ENODEV;
+
+ if (now.tv_nsec < (NSEC_PER_SEC >> 1))
+ rtc_time_to_tm(now.tv_sec, &tm);
+ else
+ rtc_time_to_tm(now.tv_sec + 1, &tm);
+
+ rtc = rtc_class_open(CONFIG_RTC_HCTOSYS_DEVICE);
+ if (rtc) {
+ /* rtc_hctosys exclusively uses UTC, so we call set_time here,
+ * not set_mmss. */
+ if (rtc->ops && (rtc->ops->set_time || rtc->ops->set_mmss))
+ err = rtc_set_time(rtc, &tm);
+ rtc_class_close(rtc);
+ }
+
+ return err;
+}