1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2019 BayLibre, SAS 4 * 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 14 struct meson_vrtc_data { 15 void __iomem *io_alarm; 16 struct rtc_device *rtc; 17 unsigned long alarm_time; 18 bool enabled; 19 }; 20 21 static 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 32 static 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 38 static 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 else 46 vrtc->alarm_time = 0; 47 48 return 0; 49 } 50 51 static 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 59 static 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 65 static 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 89 static 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 } 117 118 static 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 } 128 129 static SIMPLE_DEV_PM_OPS(meson_vrtc_pm_ops, 130 meson_vrtc_suspend, meson_vrtc_resume); 131 132 static const struct of_device_id meson_vrtc_dt_match[] = { 133 { .compatible = "amlogic,meson-vrtc"}, 134 {}, 135 }; 136 MODULE_DEVICE_TABLE(of, meson_vrtc_dt_match); 137 138 static 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 }; 146 147 module_platform_driver(meson_vrtc_driver); 148 149 MODULE_DESCRIPTION("Amlogic Virtual Wakeup RTC Timer driver"); 150 MODULE_LICENSE("GPL"); 151