LXR linux/arch/arm/mach-s3c64xx/cpuidle.c

   1/* linux/arch/arm/mach-s3c64xx/cpuidle.c
   2 *
   3 * Copyright (c) 2011 Wolfson Microelectronics, plc
   4 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
   5 *              http://www.samsung.com
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10*/
  11
  12#include <linux/kernel.h>
  13#include <linux/init.h>
  14#include <linux/cpuidle.h>
  15#include <linux/io.h>
  16#include <linux/export.h>
  17#include <linux/time.h>
  18
  19#include <asm/proc-fns.h>
  20
  21#include <mach/map.h>
  22
  23#include "regs-sys.h"
  24#include "regs-syscon-power.h"
  25
  26static int s3c64xx_enter_idle(struct cpuidle_device *dev,
  27                              struct cpuidle_driver *drv,
  28                              int index)
  29{
  30        unsigned long tmp;
  31
  32        /* Setup PWRCFG to enter idle mode */
  33        tmp = __raw_readl(S3C64XX_PWR_CFG);
  34        tmp &= ~S3C64XX_PWRCFG_CFG_WFI_MASK;
  35        tmp |= S3C64XX_PWRCFG_CFG_WFI_IDLE;
  36        __raw_writel(tmp, S3C64XX_PWR_CFG);
  37
  38        cpu_do_idle();
  39
  40        return index;
  41}
  42
  43static struct cpuidle_driver s3c64xx_cpuidle_driver = {
  44        .name   = "s3c64xx_cpuidle",
  45        .owner  = THIS_MODULE,
  46        .states = {
  47                {
  48                        .enter            = s3c64xx_enter_idle,
  49                        .exit_latency     = 1,
  50                        .target_residency = 1,
  51                        .flags            = CPUIDLE_FLAG_TIME_VALID,
  52                        .name             = "IDLE",
  53                        .desc             = "System active, ARM gated",
  54                },
  55        },
  56        .state_count = 1,
  57};
  58
  59static int __init s3c64xx_init_cpuidle(void)
  60{
  61        return cpuidle_register(&s3c64xx_cpuidle_driver, NULL);
  62}
  63device_initcall(s3c64xx_init_cpuidle);
  64