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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2019 BayLibre, SAS4 * Author: Neil Armstrong <narmstrong@baylibre.com>5 * Copyright (C) 2015 Amlogic, Inc. All rights reserved.6 */7#include <linux/module.h>8#include <linux/platform_device.h>9#include <linux/rtc.h>10#include <linux/io.h>11#include <linux/of.h>12#include <linux/time64.h>13 14struct meson_vrtc_data {15 void __iomem *io_alarm;16 struct rtc_device *rtc;17 unsigned long alarm_time;18 bool enabled;19};20 21static int meson_vrtc_read_time(struct device *dev, struct rtc_time *tm)22{23 struct timespec64 time;24 25 dev_dbg(dev, "%s\n", __func__);26 ktime_get_real_ts64(&time);27 rtc_time64_to_tm(time.tv_sec, tm);28 29 return 0;30}31 32static void meson_vrtc_set_wakeup_time(struct meson_vrtc_data *vrtc,33 unsigned long time)34{35 writel_relaxed(time, vrtc->io_alarm);36}37 38static int meson_vrtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)39{40 struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);41 42 dev_dbg(dev, "%s: alarm->enabled=%d\n", __func__, alarm->enabled);43 if (alarm->enabled)44 vrtc->alarm_time = rtc_tm_to_time64(&alarm->time);45 else46 vrtc->alarm_time = 0;47 48 return 0;49}50 51static int meson_vrtc_alarm_irq_enable(struct device *dev, unsigned int enabled)52{53 struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);54 55 vrtc->enabled = enabled;56 return 0;57}58 59static const struct rtc_class_ops meson_vrtc_ops = {60 .read_time = meson_vrtc_read_time,61 .set_alarm = meson_vrtc_set_alarm,62 .alarm_irq_enable = meson_vrtc_alarm_irq_enable,63};64 65static int meson_vrtc_probe(struct platform_device *pdev)66{67 struct meson_vrtc_data *vrtc;68 69 vrtc = devm_kzalloc(&pdev->dev, sizeof(*vrtc), GFP_KERNEL);70 if (!vrtc)71 return -ENOMEM;72 73 vrtc->io_alarm = devm_platform_ioremap_resource(pdev, 0);74 if (IS_ERR(vrtc->io_alarm))75 return PTR_ERR(vrtc->io_alarm);76 77 device_init_wakeup(&pdev->dev, 1);78 79 platform_set_drvdata(pdev, vrtc);80 81 vrtc->rtc = devm_rtc_allocate_device(&pdev->dev);82 if (IS_ERR(vrtc->rtc))83 return PTR_ERR(vrtc->rtc);84 85 vrtc->rtc->ops = &meson_vrtc_ops;86 return devm_rtc_register_device(vrtc->rtc);87}88 89static int __maybe_unused meson_vrtc_suspend(struct device *dev)90{91 struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);92 93 dev_dbg(dev, "%s\n", __func__);94 if (vrtc->alarm_time) {95 unsigned long local_time;96 long alarm_secs;97 struct timespec64 time;98 99 ktime_get_real_ts64(&time);100 local_time = time.tv_sec;101 102 dev_dbg(dev, "alarm_time = %lus, local_time=%lus\n",103 vrtc->alarm_time, local_time);104 alarm_secs = vrtc->alarm_time - local_time;105 if (alarm_secs > 0) {106 meson_vrtc_set_wakeup_time(vrtc, alarm_secs);107 dev_dbg(dev, "system will wakeup in %lds.\n",108 alarm_secs);109 } else {110 dev_err(dev, "alarm time already passed: %lds.\n",111 alarm_secs);112 }113 }114 115 return 0;116}117 118static int __maybe_unused meson_vrtc_resume(struct device *dev)119{120 struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);121 122 dev_dbg(dev, "%s\n", __func__);123 124 vrtc->alarm_time = 0;125 meson_vrtc_set_wakeup_time(vrtc, 0);126 return 0;127}128 129static SIMPLE_DEV_PM_OPS(meson_vrtc_pm_ops,130 meson_vrtc_suspend, meson_vrtc_resume);131 132static const struct of_device_id meson_vrtc_dt_match[] = {133 { .compatible = "amlogic,meson-vrtc"},134 {},135};136MODULE_DEVICE_TABLE(of, meson_vrtc_dt_match);137 138static struct platform_driver meson_vrtc_driver = {139 .probe = meson_vrtc_probe,140 .driver = {141 .name = "meson-vrtc",142 .of_match_table = meson_vrtc_dt_match,143 .pm = &meson_vrtc_pm_ops,144 },145};146 147module_platform_driver(meson_vrtc_driver);148 149MODULE_DESCRIPTION("Amlogic Virtual Wakeup RTC Timer driver");150MODULE_LICENSE("GPL");151