acrn-kernel/arch/powerpc/sysdev/fsl_pmc.c

93 lines
2.0 KiB
C

/*
* Suspend/resume support
*
* Copyright 2009 MontaVista Software, Inc.
*
* Author: Anton Vorontsov <avorontsov@ru.mvista.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/init.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/suspend.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/of_platform.h>
struct pmc_regs {
__be32 devdisr;
__be32 devdisr2;
__be32 :32;
__be32 :32;
__be32 pmcsr;
#define PMCSR_SLP (1 << 17)
};
static struct device *pmc_dev;
static struct pmc_regs __iomem *pmc_regs;
static int pmc_suspend_enter(suspend_state_t state)
{
int ret;
setbits32(&pmc_regs->pmcsr, PMCSR_SLP);
/* At this point, the CPU is asleep. */
/* Upon resume, wait for SLP bit to be clear. */
ret = spin_event_timeout((in_be32(&pmc_regs->pmcsr) & PMCSR_SLP) == 0,
10000, 10) ? 0 : -ETIMEDOUT;
if (ret)
dev_err(pmc_dev, "tired waiting for SLP bit to clear\n");
return ret;
}
static int pmc_suspend_valid(suspend_state_t state)
{
if (state != PM_SUSPEND_STANDBY)
return 0;
return 1;
}
static const struct platform_suspend_ops pmc_suspend_ops = {
.valid = pmc_suspend_valid,
.enter = pmc_suspend_enter,
};
static int pmc_probe(struct platform_device *ofdev,
const struct of_device_id *id)
{
pmc_regs = of_iomap(ofdev->dev.of_node, 0);
if (!pmc_regs)
return -ENOMEM;
pmc_dev = &ofdev->dev;
suspend_set_ops(&pmc_suspend_ops);
return 0;
}
static const struct of_device_id pmc_ids[] = {
{ .compatible = "fsl,mpc8548-pmc", },
{ .compatible = "fsl,mpc8641d-pmc", },
{ },
};
static struct of_platform_driver pmc_driver = {
.driver = {
.name = "fsl-pmc",
.owner = THIS_MODULE,
.of_match_table = pmc_ids,
},
.probe = pmc_probe,
};
static int __init pmc_init(void)
{
return of_register_platform_driver(&pmc_driver);
}
device_initcall(pmc_init);