linux/arch/arm/mach-s3c24xx/pm.c

// SPDX-License-Identifier: GPL-2.0+
//
// Copyright (c) 2004-2006 Simtec Electronics
//	Ben Dooks <ben@simtec.co.uk>
//
// S3C24XX Power Manager (Suspend-To-RAM) support
//
// See Documentation/arm/samsung-s3c24xx/suspend.rst for more information
//
// Parts based on arch/arm/mach-pxa/pm.c
//
// Thanks to Dimitry Andric for debugging

#include <linux/init.h>
#include <linux/suspend.h>
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/serial_core.h>
#include <linux/serial_s3c.h>
#include <linux/io.h>

#include <mach/regs-clock.h>
#include <mach/regs-gpio.h>
#include <mach/regs-irq.h>
#include <mach/gpio-samsung.h>

#include <asm/mach/time.h>

#include <plat/gpio-cfg.h>
#include <plat/pm.h>

#include "regs-mem.h"

#define PFX "s3c24xx-pm: "

#ifdef CONFIG_PM_SLEEP
static struct sleep_save core_save[] = {
	/* we restore the timings here, with the proviso that the board
	 * brings the system up in an slower, or equal frequency setting
	 * to the original system.
	 *
	 * if we cannot guarantee this, then things are going to go very
	 * wrong here, as we modify the refresh and both pll settings.
	 */

	SAVE_ITEM(S3C2410_BWSCON),
	SAVE_ITEM(S3C2410_BANKCON0),
	SAVE_ITEM(S3C2410_BANKCON1),
	SAVE_ITEM(S3C2410_BANKCON2),
	SAVE_ITEM(S3C2410_BANKCON3),
	SAVE_ITEM(S3C2410_BANKCON4),
	SAVE_ITEM(S3C2410_BANKCON5),
};
#endif

/* s3c_pm_check_resume_pin
 *
 * check to see if the pin is configured correctly for sleep mode, and
 * make any necessary adjustments if it is not
*/

static void s3c_pm_check_resume_pin(unsigned int pin, unsigned int irqoffs)
{
	unsigned long irqstate;
	unsigned long pinstate;
	int irq = gpio_to_irq(pin);

	if (irqoffs < 4)
		irqstate = s3c_irqwake_intmask & (1L<<irqoffs);
	else
		irqstate = s3c_irqwake_eintmask & (1L<<irqoffs);

	pinstate = s3c_gpio_getcfg(pin);

	if (!irqstate) {
		if (pinstate == S3C2410_GPIO_IRQ)
			S3C_PMDBG("Leaving IRQ %d (pin %d) as is\n", irq, pin);
	} else {
		if (pinstate == S3C2410_GPIO_IRQ) {
			S3C_PMDBG("Disabling IRQ %d (pin %d)\n", irq, pin);
			s3c_gpio_cfgpin(pin, S3C2410_GPIO_INPUT);
		}
	}
}

/* s3c_pm_configure_extint
 *
 * configure all external interrupt pins
*/

void s3c_pm_configure_extint(void)
{
	int pin;

	/* for each of the external interrupts (EINT0..EINT15) we
	 * need to check whether it is an external interrupt source,
	 * and then configure it as an input if it is not
	*/

	for (pin = S3C2410_GPF(0); pin <= S3C2410_GPF(7); pin++) {
		s3c_pm_check_resume_pin(pin, pin - S3C2410_GPF(0));
	}

	for (pin = S3C2410_GPG(0); pin <= S3C2410_GPG(7); pin++) {
		s3c_pm_check_resume_pin(pin, (pin - S3C2410_GPG(0))+8);
	}
}

#ifdef CONFIG_PM_SLEEP
void s3c_pm_restore_core(void)
{
	s3c_pm_do_restore_core(core_save, ARRAY_SIZE(core_save));
}

void s3c_pm_save_core(void)
{
	s3c_pm_do_save(core_save, ARRAY_SIZE(core_save));
}
#endif