From aa0be0f4659f91f31e45adc422b1788cb36ffddc Mon Sep 17 00:00:00 2001 From: John Stultz Date: Thu, 20 Jan 2011 15:26:12 -0800 Subject: [PATCH] RTC: Propagate error handling via rtc_timer_enqueue properly In cases where RTC hardware does not support alarms, the virtualized RTC interfaces did not have a way to propagate the error up to userland. This patch extends rtc_timer_enqueue so it catches errors from the hardware and returns them upwards to the virtualized interfaces. To simplify error handling, it also internalizes the management of the timer->enabled bit into rtc_timer_enqueue and rtc_timer_remove. Also makes rtc_timer_enqueue and rtc_timer_remove static. Reported-by: David Daney Reported-by: Andreas Schwab Reported-by: Geert Uytterhoeven Diagnosed-by: David Daney Tested-by: David Daney Signed-off-by: John Stultz LKML-Reference: <1295565973-14358-1-git-send-email-john.stultz@linaro.org> Signed-off-by: Thomas Gleixner --- drivers/rtc/interface.c | 49 +++++++++++++++++++++++------------------ include/linux/rtc.h | 2 -- 2 files changed, 28 insertions(+), 23 deletions(-) diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index 90384b9f6b2c..f1ba2c696528 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -16,6 +16,9 @@ #include #include +static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer); +static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer); + static int __rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm) { int err; @@ -175,16 +178,14 @@ int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) return err; if (rtc->aie_timer.enabled) { rtc_timer_remove(rtc, &rtc->aie_timer); - rtc->aie_timer.enabled = 0; } rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time); rtc->aie_timer.period = ktime_set(0, 0); if (alarm->enabled) { - rtc->aie_timer.enabled = 1; - rtc_timer_enqueue(rtc, &rtc->aie_timer); + err = rtc_timer_enqueue(rtc, &rtc->aie_timer); } mutex_unlock(&rtc->ops_lock); - return 0; + return err; } EXPORT_SYMBOL_GPL(rtc_set_alarm); @@ -195,15 +196,15 @@ int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled) return err; if (rtc->aie_timer.enabled != enabled) { - if (enabled) { - rtc->aie_timer.enabled = 1; - rtc_timer_enqueue(rtc, &rtc->aie_timer); - } else { + if (enabled) + err = rtc_timer_enqueue(rtc, &rtc->aie_timer); + else rtc_timer_remove(rtc, &rtc->aie_timer); - rtc->aie_timer.enabled = 0; - } } + if (err) + return err; + if (!rtc->ops) err = -ENODEV; else if (!rtc->ops->alarm_irq_enable) @@ -235,12 +236,9 @@ int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled) now = rtc_tm_to_ktime(tm); rtc->uie_rtctimer.node.expires = ktime_add(now, onesec); rtc->uie_rtctimer.period = ktime_set(1, 0); - rtc->uie_rtctimer.enabled = 1; - rtc_timer_enqueue(rtc, &rtc->uie_rtctimer); - } else { + err = rtc_timer_enqueue(rtc, &rtc->uie_rtctimer); + } else rtc_timer_remove(rtc, &rtc->uie_rtctimer); - rtc->uie_rtctimer.enabled = 0; - } out: mutex_unlock(&rtc->ops_lock); @@ -488,10 +486,13 @@ EXPORT_SYMBOL_GPL(rtc_irq_set_freq); * Enqueues a timer onto the rtc devices timerqueue and sets * the next alarm event appropriately. * + * Sets the enabled bit on the added timer. + * * Must hold ops_lock for proper serialization of timerqueue */ -void rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) +static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) { + timer->enabled = 1; timerqueue_add(&rtc->timerqueue, &timer->node); if (&timer->node == timerqueue_getnext(&rtc->timerqueue)) { struct rtc_wkalrm alarm; @@ -501,7 +502,13 @@ void rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) err = __rtc_set_alarm(rtc, &alarm); if (err == -ETIME) schedule_work(&rtc->irqwork); + else if (err) { + timerqueue_del(&rtc->timerqueue, &timer->node); + timer->enabled = 0; + return err; + } } + return 0; } /** @@ -512,13 +519,15 @@ void rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) * Removes a timer onto the rtc devices timerqueue and sets * the next alarm event appropriately. * + * Clears the enabled bit on the removed timer. + * * Must hold ops_lock for proper serialization of timerqueue */ -void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer) +static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer) { struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue); timerqueue_del(&rtc->timerqueue, &timer->node); - + timer->enabled = 0; if (next == &timer->node) { struct rtc_wkalrm alarm; int err; @@ -626,8 +635,7 @@ int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer* timer, timer->node.expires = expires; timer->period = period; - timer->enabled = 1; - rtc_timer_enqueue(rtc, timer); + ret = rtc_timer_enqueue(rtc, timer); mutex_unlock(&rtc->ops_lock); return ret; @@ -645,7 +653,6 @@ int rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer* timer) mutex_lock(&rtc->ops_lock); if (timer->enabled) rtc_timer_remove(rtc, timer); - timer->enabled = 0; mutex_unlock(&rtc->ops_lock); return ret; } diff --git a/include/linux/rtc.h b/include/linux/rtc.h index ea760698e6fe..a0b639f8e805 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -244,8 +244,6 @@ int rtc_register(rtc_task_t *task); int rtc_unregister(rtc_task_t *task); int rtc_control(rtc_task_t *t, unsigned int cmd, unsigned long arg); -void rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer); -void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer); void rtc_timer_init(struct rtc_timer *timer, void (*f)(void* p), void* data); int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer* timer, ktime_t expires, ktime_t period);