linux/drivers/cpuidle/cpuidle-at91.c
Thomas Gleixner 3bb165608e treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_56.RULE (part 2)
Based on the normalized pattern:

    this file is licensed under the terms of the gnu general public
    license version 2 this program is licensed as is without any warranty
    of any kind whether express or implied

extracted by the scancode license scanner the SPDX license identifier

    GPL-2.0-only

has been chosen to replace the boilerplate/reference.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-10 14:51:35 +02:00

63 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* based on arch/arm/mach-kirkwood/cpuidle.c
*
* CPU idle support for AT91 SoC
*
* The cpu idle uses wait-for-interrupt and RAM self refresh in order
* to implement two idle states -
* #1 wait-for-interrupt
* #2 wait-for-interrupt and RAM self refresh
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/cpuidle.h>
#include <linux/io.h>
#include <linux/export.h>
#include <asm/cpuidle.h>
#define AT91_MAX_STATES 2
static void (*at91_standby)(void);
/* Actual code that puts the SoC in different idle states */
static int at91_enter_idle(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
at91_standby();
return index;
}
static struct cpuidle_driver at91_idle_driver = {
.name = "at91_idle",
.owner = THIS_MODULE,
.states[0] = ARM_CPUIDLE_WFI_STATE,
.states[1] = {
.enter = at91_enter_idle,
.exit_latency = 10,
.target_residency = 10000,
.name = "RAM_SR",
.desc = "WFI and DDR Self Refresh",
},
.state_count = AT91_MAX_STATES,
};
/* Initialize CPU idle by registering the idle states */
static int at91_cpuidle_probe(struct platform_device *dev)
{
at91_standby = (void *)(dev->dev.platform_data);
return cpuidle_register(&at91_idle_driver, NULL);
}
static struct platform_driver at91_cpuidle_driver = {
.driver = {
.name = "cpuidle-at91",
},
.probe = at91_cpuidle_probe,
};
builtin_platform_driver(at91_cpuidle_driver);