From: Stephen Boyd <swboyd@xxxxxxxxxxxx> [ Upstream commit c79108bd19a8490315847e0c95ac6526fcd8e770 ] The alarmtimer_suspend() function will fail if an RTC device is on a bus such as SPI or i2c and that RTC device registers and probes after alarmtimer_init() registers and probes the 'alarmtimer' platform device. This is because system wide suspend suspends devices in the reverse order of their probe. When alarmtimer_suspend() attempts to program the RTC for a wakeup it will try to program an RTC device on a bus that has already been suspended. Move the alarmtimer device registration to happen when the RTC which is used for wakeup is registered. Register the 'alarmtimer' platform device as a child of the RTC device too, so that it can be guaranteed that the RTC device won't be suspended when alarmtimer_suspend() is called. Reported-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200124055849.154411-2-swboyd@xxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- kernel/time/alarmtimer.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index 4b11f0309eee4..b97401f6bc232 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -88,6 +88,7 @@ static int alarmtimer_rtc_add_device(struct device *dev, unsigned long flags; struct rtc_device *rtc = to_rtc_device(dev); struct wakeup_source *__ws; + struct platform_device *pdev; int ret = 0; if (rtcdev) @@ -99,9 +100,11 @@ static int alarmtimer_rtc_add_device(struct device *dev, return -1; __ws = wakeup_source_register(dev, "alarmtimer"); + pdev = platform_device_register_data(dev, "alarmtimer", + PLATFORM_DEVID_AUTO, NULL, 0); spin_lock_irqsave(&rtcdev_lock, flags); - if (!rtcdev) { + if (__ws && !IS_ERR(pdev) && !rtcdev) { if (!try_module_get(rtc->owner)) { ret = -1; goto unlock; @@ -112,10 +115,14 @@ static int alarmtimer_rtc_add_device(struct device *dev, get_device(dev); ws = __ws; __ws = NULL; + pdev = NULL; + } else { + ret = -1; } unlock: spin_unlock_irqrestore(&rtcdev_lock, flags); + platform_device_unregister(pdev); wakeup_source_unregister(__ws); return ret; @@ -876,8 +883,7 @@ static struct platform_driver alarmtimer_driver = { */ static int __init alarmtimer_init(void) { - struct platform_device *pdev; - int error = 0; + int error; int i; alarmtimer_rtc_timer_init(); @@ -900,15 +906,7 @@ static int __init alarmtimer_init(void) if (error) goto out_if; - pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0); - if (IS_ERR(pdev)) { - error = PTR_ERR(pdev); - goto out_drv; - } return 0; - -out_drv: - platform_driver_unregister(&alarmtimer_driver); out_if: alarmtimer_rtc_interface_remove(); return error; -- 2.20.1
