1 /*
2 * Support for OLPC XO-1 Real Time Clock (RTC)
3 *
4 * Copyright (C) 2011 One Laptop per Child
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12 #include <linux/mc146818rtc.h>
13 #include <linux/platform_device.h>
14 #include <linux/rtc.h>
15 #include <linux/of.h>
16
17 #include <asm/msr.h>
18 #include <asm/olpc.h>
19 #include <asm/x86_init.h>
20
rtc_wake_on(struct device * dev)21 static void rtc_wake_on(struct device *dev)
22 {
23 olpc_xo1_pm_wakeup_set(CS5536_PM_RTC);
24 }
25
rtc_wake_off(struct device * dev)26 static void rtc_wake_off(struct device *dev)
27 {
28 olpc_xo1_pm_wakeup_clear(CS5536_PM_RTC);
29 }
30
31 static struct resource rtc_platform_resource[] = {
32 [0] = {
33 .start = RTC_PORT(0),
34 .end = RTC_PORT(1),
35 .flags = IORESOURCE_IO,
36 },
37 [1] = {
38 .start = RTC_IRQ,
39 .end = RTC_IRQ,
40 .flags = IORESOURCE_IRQ,
41 }
42 };
43
44 static struct cmos_rtc_board_info rtc_info = {
45 .rtc_day_alarm = 0,
46 .rtc_mon_alarm = 0,
47 .rtc_century = 0,
48 .wake_on = rtc_wake_on,
49 .wake_off = rtc_wake_off,
50 };
51
52 static struct platform_device xo1_rtc_device = {
53 .name = "rtc_cmos",
54 .id = -1,
55 .num_resources = ARRAY_SIZE(rtc_platform_resource),
56 .dev.platform_data = &rtc_info,
57 .resource = rtc_platform_resource,
58 };
59
xo1_rtc_init(void)60 static int __init xo1_rtc_init(void)
61 {
62 int r;
63 struct device_node *node;
64
65 node = of_find_compatible_node(NULL, NULL, "olpc,xo1-rtc");
66 if (!node)
67 return 0;
68 of_node_put(node);
69
70 pr_info("olpc-xo1-rtc: Initializing OLPC XO-1 RTC\n");
71 rdmsrl(MSR_RTC_DOMA_OFFSET, rtc_info.rtc_day_alarm);
72 rdmsrl(MSR_RTC_MONA_OFFSET, rtc_info.rtc_mon_alarm);
73 rdmsrl(MSR_RTC_CEN_OFFSET, rtc_info.rtc_century);
74
75 r = platform_device_register(&xo1_rtc_device);
76 if (r)
77 return r;
78
79 x86_platform.legacy.rtc = 0;
80
81 device_init_wakeup(&xo1_rtc_device.dev, 1);
82 return 0;
83 }
84 arch_initcall(xo1_rtc_init);
85