summaryrefslogtreecommitdiff
path: root/drivers/rtc/rtc-meson-vrtc.c
blob: 648fa362ec447b0072e3f56fa8efd38e234d6e97 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2019 BayLibre, SAS
 * Author: Neil Armstrong <narmstrong@baylibre.com>
 * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
 */
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/time64.h>

struct meson_vrtc_data {
	void __iomem *io_alarm;
	struct rtc_device *rtc;
	unsigned long alarm_time;
	bool enabled;
};

static int meson_vrtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct timespec64 time;

	dev_dbg(dev, "%s\n", __func__);
	ktime_get_real_ts64(&time);
	rtc_time64_to_tm(time.tv_sec, tm);

	return 0;
}

static void meson_vrtc_set_wakeup_time(struct meson_vrtc_data *vrtc,
				       unsigned long time)
{
	writel_relaxed(time, vrtc->io_alarm);
}

static int meson_vrtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);

	dev_dbg(dev, "%s: alarm->enabled=%d\n", __func__, alarm->enabled);
	if (alarm->enabled)
		vrtc->alarm_time = rtc_tm_to_time64(&alarm->time);
	else
		vrtc->alarm_time = 0;

	return 0;
}

static int meson_vrtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
	struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);

	vrtc->enabled = enabled;
	return 0;
}

static const struct rtc_class_ops meson_vrtc_ops = {
	.read_time = meson_vrtc_read_time,
	.set_alarm = meson_vrtc_set_alarm,
	.alarm_irq_enable = meson_vrtc_alarm_irq_enable,
};

static int meson_vrtc_probe(struct platform_device *pdev)
{
	struct meson_vrtc_data *vrtc;

	vrtc = devm_kzalloc(&pdev->dev, sizeof(*vrtc), GFP_KERNEL);
	if (!vrtc)
		return -ENOMEM;

	vrtc->io_alarm = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(vrtc->io_alarm))
		return PTR_ERR(vrtc->io_alarm);

	device_init_wakeup(&pdev->dev, 1);

	platform_set_drvdata(pdev, vrtc);

	vrtc->rtc = devm_rtc_allocate_device(&pdev->dev);
	if (IS_ERR(vrtc->rtc))
		return PTR_ERR(vrtc->rtc);

	vrtc->rtc->ops = &meson_vrtc_ops;
	return devm_rtc_register_device(vrtc->rtc);
}

static int __maybe_unused meson_vrtc_suspend(struct device *dev)
{
	struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);

	dev_dbg(dev, "%s\n", __func__);
	if (vrtc->alarm_time) {
		unsigned long local_time;
		long alarm_secs;
		struct timespec64 time;

		ktime_get_real_ts64(&time);
		local_time = time.tv_sec;

		dev_dbg(dev, "alarm_time = %lus, local_time=%lus\n",
			vrtc->alarm_time, local_time);
		alarm_secs = vrtc->alarm_time - local_time;
		if (alarm_secs > 0) {
			meson_vrtc_set_wakeup_time(vrtc, alarm_secs);
			dev_dbg(dev, "system will wakeup in %lds.\n",
				alarm_secs);
		} else {
			dev_err(dev, "alarm time already passed: %lds.\n",
				alarm_secs);
		}
	}

	return 0;
}

static int __maybe_unused meson_vrtc_resume(struct device *dev)
{
	struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);

	dev_dbg(dev, "%s\n", __func__);

	vrtc->alarm_time = 0;
	meson_vrtc_set_wakeup_time(vrtc, 0);
	return 0;
}

static SIMPLE_DEV_PM_OPS(meson_vrtc_pm_ops,
			 meson_vrtc_suspend, meson_vrtc_resume);

static const struct of_device_id meson_vrtc_dt_match[] = {
	{ .compatible = "amlogic,meson-vrtc"},
	{},
};
MODULE_DEVICE_TABLE(of, meson_vrtc_dt_match);

static struct platform_driver meson_vrtc_driver = {
	.probe = meson_vrtc_probe,
	.driver = {
		.name = "meson-vrtc",
		.of_match_table = meson_vrtc_dt_match,
		.pm = &meson_vrtc_pm_ops,
	},
};

module_platform_driver(meson_vrtc_driver);

MODULE_DESCRIPTION("Amlogic Virtual Wakeup RTC Timer driver");
MODULE_LICENSE("GPL");