ARM: mx51: Add support for low power suspend on MX51

obj-y   := cpu.o mm.o clock-mx51-mx53.o devices.o ehci.o system.o

obj-y   := cpu.o mm.o clock-mx51-mx53.o devices.o ehci.o system.o

obj-$(CONFIG_SOC_IMX50) += mm-mx50.o

obj-$(CONFIG_SOC_IMX50) += mm-mx50.o

obj-$(CONFIG_PM) += pm-imx5.o

obj-$(CONFIG_CPU_FREQ_IMX)    += cpu_op-mx51.o

obj-$(CONFIG_CPU_FREQ_IMX)    += cpu_op-mx51.o

obj-$(CONFIG_MACH_MX51_BABBAGE) += board-mx51_babbage.o

obj-$(CONFIG_MACH_MX51_BABBAGE) += board-mx51_babbage.o

obj-$(CONFIG_MACH_MX51_3DS) += board-mx51_3ds.o

obj-$(CONFIG_MACH_MX51_3DS) += board-mx51_3ds.o

/*

 *  Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.

 *

 * The code contained herein is licensed under the GNU General Public

 * License. You may obtain a copy of the GNU General Public License

 * Version 2 or later at the following locations:

 *

 * http://www.opensource.org/licenses/gpl-license.html

 * http://www.gnu.org/copyleft/gpl.html

 */

#include <linux/suspend.h>

#include <linux/clk.h>

#include <linux/io.h>

#include <linux/err.h>

#include <asm/cacheflush.h>

#include <asm/tlbflush.h>

#include <mach/system.h>

#include "crm_regs.h"

static struct clk *gpc_dvfs_clk;

static int mx5_suspend_enter(suspend_state_t state)

{

	clk_enable(gpc_dvfs_clk);

	switch (state) {

	case PM_SUSPEND_MEM:

		mx5_cpu_lp_set(STOP_POWER_OFF);

		break;

	case PM_SUSPEND_STANDBY:

		mx5_cpu_lp_set(WAIT_UNCLOCKED_POWER_OFF);

		break;

	default:

		return -EINVAL;

	}

	if (state == PM_SUSPEND_MEM) {

		local_flush_tlb_all();

		flush_cache_all();

		/*clear the EMPGC0/1 bits */

		__raw_writel(0, MXC_SRPG_EMPGC0_SRPGCR);

		__raw_writel(0, MXC_SRPG_EMPGC1_SRPGCR);

	}

	cpu_do_idle();

	clk_disable(gpc_dvfs_clk);

	return 0;

}

static int mx5_pm_valid(suspend_state_t state)

{

	return (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX);

}

static const struct platform_suspend_ops mx5_suspend_ops = {

	.valid = mx5_pm_valid,

	.enter = mx5_suspend_enter,

};

static int __init mx5_pm_init(void)

{

	if (gpc_dvfs_clk == NULL)

		gpc_dvfs_clk = clk_get(NULL, "gpc_dvfs");

	if (!IS_ERR(gpc_dvfs_clk)) {

		if (cpu_is_mx51())

			suspend_set_ops(&mx5_suspend_ops);

	} else

		return -EPERM;

	return 0;

}

device_initcall(mx5_pm_init);