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path: root/drivers/rtc/rtc-goldfish.c
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-rw-r--r--drivers/rtc/rtc-goldfish.c206
1 files changed, 206 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-goldfish.c b/drivers/rtc/rtc-goldfish.c
new file mode 100644
index 000000000..59c0f38cc
--- /dev/null
+++ b/drivers/rtc/rtc-goldfish.c
@@ -0,0 +1,206 @@
+// SPDX-License-Identifier: GPL-2.0
+/* drivers/rtc/rtc-goldfish.c
+ *
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (C) 2017 Imagination Technologies Ltd.
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/goldfish.h>
+#include <clocksource/timer-goldfish.h>
+
+struct goldfish_rtc {
+ void __iomem *base;
+ int irq;
+ struct rtc_device *rtc;
+};
+
+static int goldfish_rtc_read_alarm(struct device *dev,
+ struct rtc_wkalrm *alrm)
+{
+ u64 rtc_alarm;
+ u64 rtc_alarm_low;
+ u64 rtc_alarm_high;
+ void __iomem *base;
+ struct goldfish_rtc *rtcdrv;
+
+ rtcdrv = dev_get_drvdata(dev);
+ base = rtcdrv->base;
+
+ rtc_alarm_low = gf_ioread32(base + TIMER_ALARM_LOW);
+ rtc_alarm_high = gf_ioread32(base + TIMER_ALARM_HIGH);
+ rtc_alarm = (rtc_alarm_high << 32) | rtc_alarm_low;
+
+ do_div(rtc_alarm, NSEC_PER_SEC);
+ memset(alrm, 0, sizeof(struct rtc_wkalrm));
+
+ rtc_time64_to_tm(rtc_alarm, &alrm->time);
+
+ if (gf_ioread32(base + TIMER_ALARM_STATUS))
+ alrm->enabled = 1;
+ else
+ alrm->enabled = 0;
+
+ return 0;
+}
+
+static int goldfish_rtc_set_alarm(struct device *dev,
+ struct rtc_wkalrm *alrm)
+{
+ struct goldfish_rtc *rtcdrv;
+ u64 rtc_alarm64;
+ u64 rtc_status_reg;
+ void __iomem *base;
+
+ rtcdrv = dev_get_drvdata(dev);
+ base = rtcdrv->base;
+
+ if (alrm->enabled) {
+ rtc_alarm64 = rtc_tm_to_time64(&alrm->time) * NSEC_PER_SEC;
+ gf_iowrite32((rtc_alarm64 >> 32), base + TIMER_ALARM_HIGH);
+ gf_iowrite32(rtc_alarm64, base + TIMER_ALARM_LOW);
+ gf_iowrite32(1, base + TIMER_IRQ_ENABLED);
+ } else {
+ /*
+ * if this function was called with enabled=0
+ * then it could mean that the application is
+ * trying to cancel an ongoing alarm
+ */
+ rtc_status_reg = gf_ioread32(base + TIMER_ALARM_STATUS);
+ if (rtc_status_reg)
+ gf_iowrite32(1, base + TIMER_CLEAR_ALARM);
+ }
+
+ return 0;
+}
+
+static int goldfish_rtc_alarm_irq_enable(struct device *dev,
+ unsigned int enabled)
+{
+ void __iomem *base;
+ struct goldfish_rtc *rtcdrv;
+
+ rtcdrv = dev_get_drvdata(dev);
+ base = rtcdrv->base;
+
+ if (enabled)
+ gf_iowrite32(1, base + TIMER_IRQ_ENABLED);
+ else
+ gf_iowrite32(0, base + TIMER_IRQ_ENABLED);
+
+ return 0;
+}
+
+static irqreturn_t goldfish_rtc_interrupt(int irq, void *dev_id)
+{
+ struct goldfish_rtc *rtcdrv = dev_id;
+ void __iomem *base = rtcdrv->base;
+
+ gf_iowrite32(1, base + TIMER_CLEAR_INTERRUPT);
+
+ rtc_update_irq(rtcdrv->rtc, 1, RTC_IRQF | RTC_AF);
+
+ return IRQ_HANDLED;
+}
+
+static int goldfish_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct goldfish_rtc *rtcdrv;
+ void __iomem *base;
+ u64 time_high;
+ u64 time_low;
+ u64 time;
+
+ rtcdrv = dev_get_drvdata(dev);
+ base = rtcdrv->base;
+
+ time_low = gf_ioread32(base + TIMER_TIME_LOW);
+ time_high = gf_ioread32(base + TIMER_TIME_HIGH);
+ time = (time_high << 32) | time_low;
+
+ do_div(time, NSEC_PER_SEC);
+
+ rtc_time64_to_tm(time, tm);
+
+ return 0;
+}
+
+static int goldfish_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct goldfish_rtc *rtcdrv;
+ void __iomem *base;
+ u64 now64;
+
+ rtcdrv = dev_get_drvdata(dev);
+ base = rtcdrv->base;
+
+ now64 = rtc_tm_to_time64(tm) * NSEC_PER_SEC;
+ gf_iowrite32((now64 >> 32), base + TIMER_TIME_HIGH);
+ gf_iowrite32(now64, base + TIMER_TIME_LOW);
+
+ return 0;
+}
+
+static const struct rtc_class_ops goldfish_rtc_ops = {
+ .read_time = goldfish_rtc_read_time,
+ .set_time = goldfish_rtc_set_time,
+ .read_alarm = goldfish_rtc_read_alarm,
+ .set_alarm = goldfish_rtc_set_alarm,
+ .alarm_irq_enable = goldfish_rtc_alarm_irq_enable
+};
+
+static int goldfish_rtc_probe(struct platform_device *pdev)
+{
+ struct goldfish_rtc *rtcdrv;
+ int err;
+
+ rtcdrv = devm_kzalloc(&pdev->dev, sizeof(*rtcdrv), GFP_KERNEL);
+ if (!rtcdrv)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, rtcdrv);
+ rtcdrv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(rtcdrv->base))
+ return PTR_ERR(rtcdrv->base);
+
+ rtcdrv->irq = platform_get_irq(pdev, 0);
+ if (rtcdrv->irq < 0)
+ return -ENODEV;
+
+ rtcdrv->rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(rtcdrv->rtc))
+ return PTR_ERR(rtcdrv->rtc);
+
+ rtcdrv->rtc->ops = &goldfish_rtc_ops;
+ rtcdrv->rtc->range_max = U64_MAX / NSEC_PER_SEC;
+
+ err = devm_request_irq(&pdev->dev, rtcdrv->irq,
+ goldfish_rtc_interrupt,
+ 0, pdev->name, rtcdrv);
+ if (err)
+ return err;
+
+ return devm_rtc_register_device(rtcdrv->rtc);
+}
+
+static const struct of_device_id goldfish_rtc_of_match[] = {
+ { .compatible = "google,goldfish-rtc", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, goldfish_rtc_of_match);
+
+static struct platform_driver goldfish_rtc = {
+ .probe = goldfish_rtc_probe,
+ .driver = {
+ .name = "goldfish_rtc",
+ .of_match_table = goldfish_rtc_of_match,
+ }
+};
+
+module_platform_driver(goldfish_rtc);
+
+MODULE_LICENSE("GPL v2");