diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/rtc/Kconfig | 12 | ||||
| -rw-r--r-- | drivers/rtc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/rtc/class.c | 7 | ||||
| -rw-r--r-- | drivers/rtc/systohc.c | 44 |
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; +} |