From 9c5150b31b49e3d89c52df9b1c1ebcea4e665ec3 Mon Sep 17 00:00:00 2001 From: Xunlei Pang Date: Fri, 12 Jun 2015 11:10:16 +0800 Subject: rtc: NTP: Add CONFIG_RTC_SYSTOHC_DEVICE for NTP synchronization Currently, CONFIG_RTC_SYSTOHC uses CONFIG_RTC_HCTOSYS_DEVICE which is originally used by CONFIG_RTC_HCTOSYS, but this rtc device has some limiations, for example, it must be battery-backed, be able to work with irq off and through system suspension, etc. So add CONFIG_RTC_SYSTOHC_DEVICE used exclusively for CONFIG_RTC_SYSTOHC, it is more lenient compared to CONFIG_RTC_HCTOSYS_DEVICE, and could be assigned any available RTC in the system. Default value is CONFIG_RTC_HCTOSYS_DEVICE which is "rtc0" by default. After this patch, NTP will sync up "rtc0" by default. Cc: Paul Bolle Signed-off-by: Xunlei Pang Signed-off-by: Alexandre Belloni --- drivers/rtc/Kconfig | 29 ++++++++++++++++++++--------- drivers/rtc/systohc.c | 2 +- 2 files changed, 21 insertions(+), 10 deletions(-) (limited to 'drivers') diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index c94bb6aded51..efaff368ee94 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -25,17 +25,9 @@ config RTC_HCTOSYS 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 - 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 || RTC_SYSTOHC = y + depends on RTC_HCTOSYS default "rtc0" help The RTC device that will be used to (re)initialize the system @@ -56,6 +48,25 @@ config RTC_HCTOSYS_DEVICE sleep states. Do not specify an RTC here unless it stays powered during all this system's supported sleep states. +config RTC_SYSTOHC + bool "Set the RTC time based on NTP synchronization" + default y + 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_SYSTOHC_DEVICE + string "RTC used to synchronize NTP adjustment" + depends on RTC_SYSTOHC + default RTC_HCTOSYS_DEVICE if RTC_HCTOSYS + default "rtc0" + help + The RTC device used for NTP synchronization. The main difference + between RTC_HCTOSYS_DEVICE and RTC_SYSTOHC_DEVICE is that this + one can sleep when setting time, because it runs in the workqueue + context. + config RTC_DEBUG bool "RTC debug support" help diff --git a/drivers/rtc/systohc.c b/drivers/rtc/systohc.c index 7728d5e32bf4..b4a68ffcd06b 100644 --- a/drivers/rtc/systohc.c +++ b/drivers/rtc/systohc.c @@ -31,7 +31,7 @@ int rtc_set_ntp_time(struct timespec64 now) else rtc_time64_to_tm(now.tv_sec + 1, &tm); - rtc = rtc_class_open(CONFIG_RTC_HCTOSYS_DEVICE); + rtc = rtc_class_open(CONFIG_RTC_SYSTOHC_DEVICE); if (rtc) { /* rtc_hctosys exclusively uses UTC, so we call set_time here, * not set_mmss. */ -- cgit v1.2.3