olpc-xo1-rtc.c

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/*
 * Support for OLPC XO-1 Real Time Clock (RTC)
 *
 * Copyright (C) 2011 One Laptop per Child
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/mc146818rtc.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/of.h>

#include <asm/msr.h>
#include <asm/olpc.h>

static void rtc_wake_on(struct device *dev)
{
    olpc_xo1_pm_wakeup_set(CS5536_PM_RTC);
}

static void rtc_wake_off(struct device *dev)
{
    olpc_xo1_pm_wakeup_clear(CS5536_PM_RTC);
}

static struct resource rtc_platform_resource[] = {
    [0] = {
        .start  = RTC_PORT(0),
        .end    = RTC_PORT(1),
        .flags  = IORESOURCE_IO,
    },
    [1] = {
        .start  = RTC_IRQ,
        .end    = RTC_IRQ,
        .flags  = IORESOURCE_IRQ,
    }
};

static struct cmos_rtc_board_info rtc_info = {
    .rtc_day_alarm = 0,
    .rtc_mon_alarm = 0,
    .rtc_century = 0,
    .wake_on = rtc_wake_on,
    .wake_off = rtc_wake_off,
};

static struct platform_device xo1_rtc_device = {
    .name = "rtc_cmos",
    .id = -1,
    .num_resources = ARRAY_SIZE(rtc_platform_resource),
    .dev.platform_data = &rtc_info,
    .resource = rtc_platform_resource,
};

static int __init xo1_rtc_init(void)
{
    int r;
    struct device_node *node;

    node = of_find_compatible_node(NULL, NULL, "olpc,xo1-rtc");
    if (!node)
        return 0;
    of_node_put(node);

    pr_info("olpc-xo1-rtc: Initializing OLPC XO-1 RTC\n");
    rdmsrl(MSR_RTC_DOMA_OFFSET, rtc_info.rtc_day_alarm);
    rdmsrl(MSR_RTC_MONA_OFFSET, rtc_info.rtc_mon_alarm);
    rdmsrl(MSR_RTC_CEN_OFFSET, rtc_info.rtc_century);

    r = platform_device_register(&xo1_rtc_device);
    if (r)
        return r;

    device_init_wakeup(&xo1_rtc_device.dev, 1);
    return 0;
}
arch_initcall(xo1_rtc_init);