1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Support for OLPC XO-1 Real Time Clock (RTC)
4 *
5 * Copyright (C) 2011 One Laptop per Child
6 */
7
8#include <linux/mc146818rtc.h>
9#include <linux/platform_device.h>
10#include <linux/rtc.h>
11#include <linux/of.h>
12
13#include <asm/msr.h>
14#include <asm/olpc.h>
15#include <asm/x86_init.h>
16
17static void rtc_wake_on(struct device *dev)
18{
19	olpc_xo1_pm_wakeup_set(CS5536_PM_RTC);
20}
21
22static void rtc_wake_off(struct device *dev)
23{
24	olpc_xo1_pm_wakeup_clear(CS5536_PM_RTC);
25}
26
27static struct resource rtc_platform_resource[] = {
28	[0] = {
29		.start	= RTC_PORT(0),
30		.end	= RTC_PORT(1),
31		.flags	= IORESOURCE_IO,
32	},
33	[1] = {
34		.start	= RTC_IRQ,
35		.end	= RTC_IRQ,
36		.flags	= IORESOURCE_IRQ,
37	}
38};
39
40static struct cmos_rtc_board_info rtc_info = {
41	.rtc_day_alarm = 0,
42	.rtc_mon_alarm = 0,
43	.rtc_century = 0,
44	.wake_on = rtc_wake_on,
45	.wake_off = rtc_wake_off,
46};
47
48static struct platform_device xo1_rtc_device = {
49	.name = "rtc_cmos",
50	.id = -1,
51	.num_resources = ARRAY_SIZE(rtc_platform_resource),
52	.dev.platform_data = &rtc_info,
53	.resource = rtc_platform_resource,
54};
55
56static int __init xo1_rtc_init(void)
57{
58	int r;
59	struct device_node *node;
60
61	node = of_find_compatible_node(NULL, NULL, "olpc,xo1-rtc");
62	if (!node)
63		return 0;
64	of_node_put(node);
65
66	pr_info("olpc-xo1-rtc: Initializing OLPC XO-1 RTC\n");
67	rdmsrl(MSR_RTC_DOMA_OFFSET, rtc_info.rtc_day_alarm);
68	rdmsrl(MSR_RTC_MONA_OFFSET, rtc_info.rtc_mon_alarm);
69	rdmsrl(MSR_RTC_CEN_OFFSET, rtc_info.rtc_century);
70
71	r = platform_device_register(&xo1_rtc_device);
72	if (r)
73		return r;
74
75	x86_platform.legacy.rtc = 0;
76
77	device_init_wakeup(&xo1_rtc_device.dev, 1);
78	return 0;
79}
80arch_initcall(xo1_rtc_init);
81