rtc: brcmstb-waketimer: allow use as non-wake alarm

The wake interrupt only fires when the system is in a suspend
state. Fortunately we have another interrupt that fires in a
non-suspend state at the L2 controller UPG_AUX_AON. Add support
for this interrupt line so we can use the alarm in a non-wake
context.

Signed-off-by: Doug Berger <opendmb@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230124201430.2502371-3-opendmb@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

diff --git a/drivers/rtc/rtc-brcmstb-waketimer.c b/drivers/rtc/rtc-brcmstb-waketimer.c
index e25f9fcd6ed1c06a2ec9a3648b4a755b20de3df2..1efa81cecc273fb3046b7e365c1d130a7a1f679b 100644 (file)
--- a/drivers/rtc/rtc-brcmstb-waketimer.c
+++ b/drivers/rtc/rtc-brcmstb-waketimer.c
@@ -28,6 +28,7 @@ struct brcmstb_waketmr {
        struct device *dev;
        void __iomem *base;
        unsigned int wake_irq;
+       unsigned int alarm_irq;
        struct notifier_block reboot_notifier;
        struct clk *clk;
        u32 rate;
@@ -56,6 +57,8 @@ static inline void brcmstb_waketmr_clear_alarm(struct brcmstb_waketmr *timer)
 {
        u32 reg;
 
+       if (timer->alarm_en && timer->alarm_irq)
+               disable_irq(timer->alarm_irq);
        timer->alarm_en = false;
        reg = readl_relaxed(timer->base + BRCMSTB_WKTMR_COUNTER);
        writel_relaxed(reg - 1, timer->base + BRCMSTB_WKTMR_ALARM);
@@ -88,7 +91,25 @@ static irqreturn_t brcmstb_waketmr_irq(int irq, void *data)
 {
        struct brcmstb_waketmr *timer = data;
 
-       pm_wakeup_event(timer->dev, 0);
+       if (!timer->alarm_irq)
+               pm_wakeup_event(timer->dev, 0);
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t brcmstb_alarm_irq(int irq, void *data)
+{
+       struct brcmstb_waketmr *timer = data;
+
+       /* Ignore spurious interrupts */
+       if (!brcmstb_waketmr_is_pending(timer))
+               return IRQ_HANDLED;
+
+       if (timer->alarm_en) {
+               if (!device_may_wakeup(timer->dev))
+                       writel_relaxed(WKTMR_ALARM_EVENT,
+                                      timer->base + BRCMSTB_WKTMR_EVENT);
+               rtc_update_irq(timer->rtc, 1, RTC_IRQF | RTC_AF);
+       }
 
        return IRQ_HANDLED;
 }
@@ -114,7 +135,7 @@ static void wktmr_read(struct brcmstb_waketmr *timer,
 static int brcmstb_waketmr_prepare_suspend(struct brcmstb_waketmr *timer)
 {
        struct device *dev = timer->dev;
-       int ret = 0;
+       int ret;
 
        if (device_may_wakeup(dev)) {
                ret = enable_irq_wake(timer->wake_irq);
@@ -122,9 +143,17 @@ static int brcmstb_waketmr_prepare_suspend(struct brcmstb_waketmr *timer)
                        dev_err(dev, "failed to enable wake-up interrupt\n");
                        return ret;
                }
+               if (timer->alarm_en && timer->alarm_irq) {
+                       ret = enable_irq_wake(timer->alarm_irq);
+                       if (ret) {
+                               dev_err(dev, "failed to enable rtc interrupt\n");
+                               disable_irq_wake(timer->wake_irq);
+                               return ret;
+                       }
+               }
        }
 
-       return ret;
+       return 0;
 }
 
 /* If enabled as a wakeup-source, arm the timer when powering off */
@@ -192,7 +221,11 @@ static int brcmstb_waketmr_alarm_enable(struct device *dev,
                    !brcmstb_waketmr_is_pending(timer))
                        return -EINVAL;
                timer->alarm_en = true;
+               if (timer->alarm_irq)
+                       enable_irq(timer->alarm_irq);
        } else if (!enabled && timer->alarm_en) {
+               if (timer->alarm_irq)
+                       disable_irq(timer->alarm_irq);
                timer->alarm_en = false;
        }
 
@@ -269,6 +302,19 @@ static int brcmstb_waketmr_probe(struct platform_device *pdev)
        if (ret < 0)
                goto err_clk;
 
+       brcmstb_waketmr_clear_alarm(timer);
+
+       /* Attempt to initialize non-wake irq */
+       ret = platform_get_irq(pdev, 1);
+       if (ret > 0) {
+               timer->alarm_irq = (unsigned int)ret;
+               ret = devm_request_irq(dev, timer->alarm_irq, brcmstb_alarm_irq,
+                                      IRQF_NO_AUTOEN, "brcmstb-waketimer-rtc",
+                                      timer);
+               if (ret < 0)
+                       timer->alarm_irq = 0;
+       }
+
        timer->reboot_notifier.notifier_call = brcmstb_waketmr_reboot;
        register_reboot_notifier(&timer->reboot_notifier);
 
@@ -317,6 +363,8 @@ static int brcmstb_waketmr_resume(struct device *dev)
                return 0;
 
        ret = disable_irq_wake(timer->wake_irq);
+       if (timer->alarm_en && timer->alarm_irq)
+               disable_irq_wake(timer->alarm_irq);
 
        brcmstb_waketmr_clear_alarm(timer);
 
@@ -346,4 +394,5 @@ module_platform_driver(brcmstb_waketmr_driver);
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Brian Norris");
 MODULE_AUTHOR("Markus Mayer");
+MODULE_AUTHOR("Doug Berger");
 MODULE_DESCRIPTION("Wake-up timer driver for STB chips");