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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_raw_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 else
46 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 int ret;
69
70 vrtc = devm_kzalloc(&pdev->dev, sizeof(*vrtc), GFP_KERNEL);
71 if (!vrtc)
72 return -ENOMEM;
73
74 vrtc->io_alarm = devm_platform_ioremap_resource(pdev, 0);
75 if (IS_ERR(vrtc->io_alarm))
76 return PTR_ERR(vrtc->io_alarm);
77
78 device_init_wakeup(&pdev->dev, 1);
79
80 platform_set_drvdata(pdev, vrtc);
81
82 vrtc->rtc = devm_rtc_allocate_device(&pdev->dev);
83 if (IS_ERR(vrtc->rtc))
84 return PTR_ERR(vrtc->rtc);
85
86 vrtc->rtc->ops = &meson_vrtc_ops;
87 ret = rtc_register_device(vrtc->rtc);
88 if (ret)
89 return ret;
90
91 return 0;
92}
93
94static int __maybe_unused meson_vrtc_suspend(struct device *dev)
95{
96 struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
97
98 dev_dbg(dev, "%s\n", __func__);
99 if (vrtc->alarm_time) {
100 unsigned long local_time;
101 long alarm_secs;
102 struct timespec64 time;
103
104 ktime_get_raw_ts64(&time);
105 local_time = time.tv_sec;
106
107 dev_dbg(dev, "alarm_time = %lus, local_time=%lus\n",
108 vrtc->alarm_time, local_time);
109 alarm_secs = vrtc->alarm_time - local_time;
110 if (alarm_secs > 0) {
111 meson_vrtc_set_wakeup_time(vrtc, alarm_secs);
112 dev_dbg(dev, "system will wakeup in %lds.\n",
113 alarm_secs);
114 } else {
115 dev_err(dev, "alarm time already passed: %lds.\n",
116 alarm_secs);
117 }
118 }
119
120 return 0;
121}
122
123static int __maybe_unused meson_vrtc_resume(struct device *dev)
124{
125 struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
126
127 dev_dbg(dev, "%s\n", __func__);
128
129 vrtc->alarm_time = 0;
130 meson_vrtc_set_wakeup_time(vrtc, 0);
131 return 0;
132}
133
134static SIMPLE_DEV_PM_OPS(meson_vrtc_pm_ops,
135 meson_vrtc_suspend, meson_vrtc_resume);
136
137static const struct of_device_id meson_vrtc_dt_match[] = {
138 { .compatible = "amlogic,meson-vrtc"},
139 {},
140};
141MODULE_DEVICE_TABLE(of, meson_vrtc_dt_match);
142
143static struct platform_driver meson_vrtc_driver = {
144 .probe = meson_vrtc_probe,
145 .driver = {
146 .name = "meson-vrtc",
147 .of_match_table = meson_vrtc_dt_match,
148 .pm = &meson_vrtc_pm_ops,
149 },
150};
151
152module_platform_driver(meson_vrtc_driver);
153
154MODULE_DESCRIPTION("Amlogic Virtual Wakeup RTC Timer driver");
155MODULE_LICENSE("GPL");
156
