arch/arm/mach-s3c2416/pm.c

   1 /* linux/arch/arm/mach-s3c2416/pm.c
   2  *
   3  * Copyright (c) 2010 Samsung Electronics Co., Ltd.
   4  *              http://www.samsung.com
   5  *
   6  * S3C2416 - PM support (Based on Ben Dooks' S3C2412 PM support)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11 */
  12
  13 #include <linux/sysdev.h>
  14 #include <linux/io.h>
  15
  16 #include <asm/cacheflush.h>
  17
  18 #include <mach/regs-power.h>
  19 #include <mach/regs-s3c2443-clock.h>
  20
  21 #include <plat/cpu.h>
  22 #include <plat/pm.h>
  23
  24 extern void s3c2412_sleep_enter(void);
  25
  26 static void s3c2416_cpu_suspend(void)
  27 {
  28         flush_cache_all();
  29
  30         /* enable wakeup sources regardless of battery state */
  31         __raw_writel(S3C2443_PWRCFG_SLEEP, S3C2443_PWRCFG);
  32
  33         /* set the mode as sleep, 2BED represents "Go to BED" */
  34         __raw_writel(0x2BED, S3C2443_PWRMODE);
  35
  36         s3c2412_sleep_enter();
  37 }
  38
  39 static void s3c2416_pm_prepare(void)
  40 {
  41         /*
  42          * write the magic value u-boot uses to check for resume into
  43          * the INFORM0 register, and ensure INFORM1 is set to the
  44          * correct address to resume from.
  45          */
  46         __raw_writel(0x2BED, S3C2412_INFORM0);
  47         __raw_writel(virt_to_phys(s3c_cpu_resume), S3C2412_INFORM1);
  48 }
  49
  50 static int s3c2416_pm_add(struct sys_device *sysdev)
  51 {
  52         pm_cpu_prep = s3c2416_pm_prepare;
  53         pm_cpu_sleep = s3c2416_cpu_suspend;
  54
  55         return 0;
  56 }
  57
  58 static int s3c2416_pm_suspend(struct sys_device *dev, pm_message_t state)
  59 {
  60         return 0;
  61 }
  62
  63 static int s3c2416_pm_resume(struct sys_device *dev)
  64 {
  65         /* unset the return-from-sleep amd inform flags */
  66         __raw_writel(0x0, S3C2443_PWRMODE);
  67         __raw_writel(0x0, S3C2412_INFORM0);
  68         __raw_writel(0x0, S3C2412_INFORM1);
  69
  70         return 0;
  71 }
  72
  73 static struct sysdev_driver s3c2416_pm_driver = {
  74         .add            = s3c2416_pm_add,
  75         .suspend        = s3c2416_pm_suspend,
  76         .resume         = s3c2416_pm_resume,
  77 };
  78
  79 static __init int s3c2416_pm_init(void)
  80 {
  81         return sysdev_driver_register(&s3c2416_sysclass, &s3c2416_pm_driver);
  82 }
  83
  84 arch_initcall(s3c2416_pm_init);