/*
 * PXA250/210 Power Management Routines
 *
 * Original code for the SA11x0:
 * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
 *
 * Modified for the PXA250 by Nicolas Pitre:
 * Copyright (c) 2002 Monta Vista Software, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License.
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/suspend.h>
#include <linux/errno.h>
#include <linux/slab.h>

#include "pm.h"

struct pxa_cpu_pm_fns *pxa_cpu_pm_fns;
static unsigned long *sleep_save;

int pxa_pm_enter(suspend_state_t state)
{
        unsigned long sleep_save_checksum = 0, checksum = 0;
        int i;

#ifdef CONFIG_IWMMXT
        /* force any iWMMXt context to ram **/
        if (elf_hwcap & HWCAP_IWMMXT)
                iwmmxt_task_disable(NULL);
#endif

        /* skip registers saving for standby */
        if (state != PM_SUSPEND_STANDBY && pxa_cpu_pm_fns->save) {
                pxa_cpu_pm_fns->save(sleep_save);
                /* before sleeping, calculate and save a checksum */
                for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++)
                        sleep_save_checksum += sleep_save[i];
        }

        /* *** go zzz *** */
        pxa_cpu_pm_fns->enter(state);

        if (state != PM_SUSPEND_STANDBY && pxa_cpu_pm_fns->restore) {
                /* after sleeping, validate the checksum */
                for (i = 0; i < pxa_cpu_pm_fns->save_count - 1; i++)
                        checksum += sleep_save[i];

                /* if invalid, display message and wait for a hardware reset */
                if (checksum != sleep_save_checksum) {

                        while (1)
                                pxa_cpu_pm_fns->enter(state);
                }
                pxa_cpu_pm_fns->restore(sleep_save);
        }

        pr_debug("*** made it back from resume\n");

        return 0;
}

EXPORT_SYMBOL_GPL(pxa_pm_enter);

static int pxa_pm_valid(suspend_state_t state)
{
        if (pxa_cpu_pm_fns)
                return pxa_cpu_pm_fns->valid(state);

        return -EINVAL;
}

int pxa_pm_prepare(void)
{
        int ret = 0;

        if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->prepare)
                ret = pxa_cpu_pm_fns->prepare();

        return ret;
}

void pxa_pm_finish(void)
{
        if (pxa_cpu_pm_fns && pxa_cpu_pm_fns->finish)
                pxa_cpu_pm_fns->finish();
}

static const struct platform_suspend_ops pxa_pm_ops = {
        .valid          = pxa_pm_valid,
        .enter          = pxa_pm_enter,
        .prepare        = pxa_pm_prepare,
        .finish         = pxa_pm_finish,
};

static int __init pxa_pm_init(void)
{
        if (!pxa_cpu_pm_fns) {
                printk(KERN_ERR "no valid pxa_cpu_pm_fns defined\n");
                return -EINVAL;
        }

        sleep_save = kmalloc_array(pxa_cpu_pm_fns->save_count,
                                   sizeof(*sleep_save),
                                   GFP_KERNEL);
        if (!sleep_save)
                return -ENOMEM;

        suspend_set_ops(&pxa_pm_ops);
        return 0;
}

device_initcall(pxa_pm_init);