Permits power state and battery life diagnosis. Feature activated by CONFIG_RTC_SHOW_TIME. Signed-off-by: Mark Salyzyn <salyzyn@xxxxxxxxxxx> v2: - react to implementation move to kernel timekeeping from rtc_lib - use late_initcall to ensure rtc_lib driver(s) are loaded --- kernel/time/rtc_show_time.c | 59 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) diff --git a/kernel/time/rtc_show_time.c b/kernel/time/rtc_show_time.c index 19a8a0cc94f0..6c7b8ae6be0c 100644 --- a/kernel/time/rtc_show_time.c +++ b/kernel/time/rtc_show_time.c @@ -6,6 +6,8 @@ * published by the Free Software Foundation. */ +#include <linux/kdebug.h> +#include <linux/reboot.h> #include <linux/rtc.h> void rtc_show_time(const char *prefix_msg) @@ -27,3 +29,60 @@ void rtc_show_time(const char *prefix_msg) #endif } EXPORT_SYMBOL(rtc_show_time); + +static int rtc_show_time_die_notify(struct notifier_block *self, + unsigned long event, void *data) +{ + if (event != DIE_OOPS) + return NOTIFY_DONE; + rtc_show_time("Oops"); + return NOTIFY_DONE; +} + +static struct notifier_block rtc_show_time_die_nb = { + .notifier_call = rtc_show_time_die_notify, + .priority = 0, +}; + +static int rtc_show_time_reboot_notify(struct notifier_block *self, + unsigned long event, void *data) +{ + const char *txt; + + switch (event) { + case SYS_RESTART: + txt = "Restart"; + break; + case SYS_HALT: + txt = "Halt"; + break; + case SYS_POWER_OFF: + txt = "Power-Off"; + break; + default: + return NOTIFY_DONE; + } + rtc_show_time(txt); + return NOTIFY_DONE; +} + +static struct notifier_block rtc_show_time_reboot_nb = { + .notifier_call = rtc_show_time_reboot_notify, + .priority = 0, +}; + +static __init int init_rtc_show_time(void) +{ + int ret; + + ret = register_die_notifier(&rtc_show_time_die_nb); + if (ret) + pr_warn("Failed to register rtc_show_time die notifier\n"); + ret = register_reboot_notifier(&rtc_show_time_reboot_nb); + if (ret) + pr_warn("Failed to register rtc_show_time reboot notifier\n"); + + return ret; +} +/* rtc driver needs to be loaded before this is truly functional */ +late_initcall(init_rtc_show_time); -- 2.14.0.rc0.284.gd933b75aa4-goog