From 47b4a457e4cc816b3fdd2ee55c65fda8ea6de051 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Wed, 5 Jul 2017 14:08:35 +0200 Subject: [PATCH] alarmtimer: Fix unavailable wake-up source in sysfs Currently the alarmtimer registers a wake-up source unconditionally, regardless of the system having a (wake-up capable) RTC or not. Hence the alarmtimer will always show up in /sys/kernel/debug/wakeup_sources, even if it is not available, and thus cannot be a wake-up source. To fix this, postpone registration until a wake-up capable RTC device is added. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Miroslav Lichvar Cc: Richard Cochran Cc: Prarit Bhargava Cc: Stephen Boyd Signed-off-by: Geert Uytterhoeven Signed-off-by: John Stultz --- kernel/time/alarmtimer.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index 0b8ff7d257ea..73a2b476e59f 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -56,9 +56,9 @@ static ktime_t freezer_delta; static DEFINE_SPINLOCK(freezer_delta_lock); #endif +#ifdef CONFIG_RTC_CLASS static struct wakeup_source *ws; -#ifdef CONFIG_RTC_CLASS /* rtc timer and device for setting alarm wakeups at suspend */ static struct rtc_timer rtctimer; static struct rtc_device *rtcdev; @@ -89,6 +89,7 @@ static int alarmtimer_rtc_add_device(struct device *dev, { unsigned long flags; struct rtc_device *rtc = to_rtc_device(dev); + struct wakeup_source *__ws; if (rtcdev) return -EBUSY; @@ -98,13 +99,20 @@ static int alarmtimer_rtc_add_device(struct device *dev, if (!device_may_wakeup(rtc->dev.parent)) return -1; + __ws = wakeup_source_register("alarmtimer"); + spin_lock_irqsave(&rtcdev_lock, flags); if (!rtcdev) { rtcdev = rtc; /* hold a reference so it doesn't go away */ get_device(dev); + ws = __ws; + __ws = NULL; } spin_unlock_irqrestore(&rtcdev_lock, flags); + + wakeup_source_unregister(__ws); + return 0; } @@ -860,7 +868,6 @@ static int __init alarmtimer_init(void) error = PTR_ERR(pdev); goto out_drv; } - ws = wakeup_source_register("alarmtimer"); return 0; out_drv: -- 2.20.1