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(tv: &time); |
27 | rtc_time64_to_tm(time: 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(tm: &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(dev: &pdev->dev, size: sizeof(*vrtc), GFP_KERNEL); |
70 | if (!vrtc) |
71 | return -ENOMEM; |
72 | |
73 | vrtc->io_alarm = devm_platform_ioremap_resource(pdev, index: 0); |
74 | if (IS_ERR(ptr: vrtc->io_alarm)) |
75 | return PTR_ERR(ptr: vrtc->io_alarm); |
76 | |
77 | device_init_wakeup(dev: &pdev->dev, enable: 1); |
78 | |
79 | platform_set_drvdata(pdev, data: vrtc); |
80 | |
81 | vrtc->rtc = devm_rtc_allocate_device(dev: &pdev->dev); |
82 | if (IS_ERR(ptr: vrtc->rtc)) |
83 | return PTR_ERR(ptr: 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(tv: &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, time: 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, time: 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 | |