LXR linux/arch/arm/mach-imx/pm-imx27.c

   1/*
   2 * i.MX27 Power Management Routines
   3 *
   4 * Based on Freescale's BSP
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License.
   8 */
   9
  10#include <linux/kernel.h>
  11#include <linux/suspend.h>
  12#include <linux/io.h>
  13
  14#include "hardware.h"
  15
  16static int mx27_suspend_enter(suspend_state_t state)
  17{
  18        u32 cscr;
  19        switch (state) {
  20        case PM_SUSPEND_MEM:
  21                /* Clear MPEN and SPEN to disable MPLL/SPLL */
  22                cscr = imx_readl(MX27_IO_ADDRESS(MX27_CCM_BASE_ADDR));
  23                cscr &= 0xFFFFFFFC;
  24                imx_writel(cscr, MX27_IO_ADDRESS(MX27_CCM_BASE_ADDR));
  25                /* Executes WFI */
  26                cpu_do_idle();
  27                break;
  28
  29        default:
  30                return -EINVAL;
  31        }
  32        return 0;
  33}
  34
  35static const struct platform_suspend_ops mx27_suspend_ops = {
  36        .enter = mx27_suspend_enter,
  37        .valid = suspend_valid_only_mem,
  38};
  39
  40static int __init mx27_pm_init(void)
  41{
  42        if (!cpu_is_mx27())
  43                return 0;
  44
  45        suspend_set_ops(&mx27_suspend_ops);
  46        return 0;
  47}
  48
  49device_initcall(mx27_pm_init);
  50