From: Doug Berger <opendmb@gmail.com> stable inclusion from stable-v6.6.2 commit e5a8fc34283e6488c000c33bbcf186f2ec254fd0 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8IW7G Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit e005a9b35b464be5b2e0194f717e90e7e496785d ] Some devices (e.g. BCM72112) use an alarm_irq interrupt that is connected to a level interrupt controller rather than an edge interrupt controller. In this case, the interrupt cannot be left enabled by the irq handler while preserving the hardware wake-up signal on wake capable devices or an interrupt storm will occur. The alarm_expired flag is introduced to allow the disabling of the interrupt when an alarm expires and to support balancing the calls to disable_irq() and enable_irq() in accordance with the existing design. Fixes: 24304a87158a ("rtc: brcmstb-waketimer: allow use as non-wake alarm") Signed-off-by: Doug Berger <opendmb@gmail.com> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Link: https://lore.kernel.org/r/20230830224747.1663044-1-opendmb@gmail.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- drivers/rtc/rtc-brcmstb-waketimer.c | 47 ++++++++++++++++++++++++++--- 1 file changed, 42 insertions(+), 5 deletions(-) diff --git a/drivers/rtc/rtc-brcmstb-waketimer.c b/drivers/rtc/rtc-brcmstb-waketimer.c index 3cdc015692ca..1a65a4e0dc00 100644 --- a/drivers/rtc/rtc-brcmstb-waketimer.c +++ b/drivers/rtc/rtc-brcmstb-waketimer.c @@ -1,6 +1,6 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * Copyright �� 2014-2017 Broadcom + * Copyright �� 2014-2023 Broadcom */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt @@ -34,6 +34,7 @@ struct brcmstb_waketmr { u32 rate; unsigned long rtc_alarm; bool alarm_en; + bool alarm_expired; }; #define BRCMSTB_WKTMR_EVENT 0x00 @@ -64,6 +65,11 @@ static inline void brcmstb_waketmr_clear_alarm(struct brcmstb_waketmr *timer) writel_relaxed(reg - 1, timer->base + BRCMSTB_WKTMR_ALARM); writel_relaxed(WKTMR_ALARM_EVENT, timer->base + BRCMSTB_WKTMR_EVENT); (void)readl_relaxed(timer->base + BRCMSTB_WKTMR_EVENT); + if (timer->alarm_expired) { + timer->alarm_expired = false; + /* maintain call balance */ + enable_irq(timer->alarm_irq); + } } static void brcmstb_waketmr_set_alarm(struct brcmstb_waketmr *timer, @@ -105,10 +111,17 @@ static irqreturn_t brcmstb_alarm_irq(int irq, void *data) return IRQ_HANDLED; if (timer->alarm_en) { - if (!device_may_wakeup(timer->dev)) + if (device_may_wakeup(timer->dev)) { + disable_irq_nosync(irq); + timer->alarm_expired = true; + } else { writel_relaxed(WKTMR_ALARM_EVENT, timer->base + BRCMSTB_WKTMR_EVENT); + } rtc_update_irq(timer->rtc, 1, RTC_IRQF | RTC_AF); + } else { + writel_relaxed(WKTMR_ALARM_EVENT, + timer->base + BRCMSTB_WKTMR_EVENT); } return IRQ_HANDLED; @@ -221,8 +234,14 @@ static int brcmstb_waketmr_alarm_enable(struct device *dev, !brcmstb_waketmr_is_pending(timer)) return -EINVAL; timer->alarm_en = true; - if (timer->alarm_irq) + if (timer->alarm_irq) { + if (timer->alarm_expired) { + timer->alarm_expired = false; + /* maintain call balance */ + enable_irq(timer->alarm_irq); + } enable_irq(timer->alarm_irq); + } } else if (!enabled && timer->alarm_en) { if (timer->alarm_irq) disable_irq(timer->alarm_irq); @@ -352,6 +371,17 @@ static int brcmstb_waketmr_suspend(struct device *dev) return brcmstb_waketmr_prepare_suspend(timer); } +static int brcmstb_waketmr_suspend_noirq(struct device *dev) +{ + struct brcmstb_waketmr *timer = dev_get_drvdata(dev); + + /* Catch any alarms occurring prior to noirq */ + if (timer->alarm_expired && device_may_wakeup(dev)) + return -EBUSY; + + return 0; +} + static int brcmstb_waketmr_resume(struct device *dev) { struct brcmstb_waketmr *timer = dev_get_drvdata(dev); @@ -368,10 +398,17 @@ static int brcmstb_waketmr_resume(struct device *dev) return ret; } +#else +#define brcmstb_waketmr_suspend NULL +#define brcmstb_waketmr_suspend_noirq NULL +#define brcmstb_waketmr_resume NULL #endif /* CONFIG_PM_SLEEP */ -static SIMPLE_DEV_PM_OPS(brcmstb_waketmr_pm_ops, - brcmstb_waketmr_suspend, brcmstb_waketmr_resume); +static const struct dev_pm_ops brcmstb_waketmr_pm_ops = { + .suspend = brcmstb_waketmr_suspend, + .suspend_noirq = brcmstb_waketmr_suspend_noirq, + .resume = brcmstb_waketmr_resume, +}; static const __maybe_unused struct of_device_id brcmstb_waketmr_of_match[] = { { .compatible = "brcm,brcmstb-waketimer" }, -- 2.25.1