LXR linux/arch/x86/platform/olpc/olpc-xo1-rtc.c

   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