1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * CLPS711X CPU idle driver
4 *
5 * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
6 */
7
8#include <linux/cpuidle.h>
9#include <linux/err.h>
10#include <linux/io.h>
11#include <linux/init.h>
12#include <linux/platform_device.h>
13
14#define CLPS711X_CPUIDLE_NAME "clps711x-cpuidle"
15
16static void __iomem *clps711x_halt;
17
18static int clps711x_cpuidle_halt(struct cpuidle_device *dev,
19 struct cpuidle_driver *drv, int index)
20{
21 writel(val: 0xaa, addr: clps711x_halt);
22
23 return index;
24}
25
26static struct cpuidle_driver clps711x_idle_driver = {
27 .name = CLPS711X_CPUIDLE_NAME,
28 .owner = THIS_MODULE,
29 .states[0] = {
30 .name = "HALT",
31 .desc = "CLPS711X HALT",
32 .enter = clps711x_cpuidle_halt,
33 .exit_latency = 1,
34 },
35 .state_count = 1,
36};
37
38static int __init clps711x_cpuidle_probe(struct platform_device *pdev)
39{
40 clps711x_halt = devm_platform_ioremap_resource(pdev, index: 0);
41 if (IS_ERR(ptr: clps711x_halt))
42 return PTR_ERR(ptr: clps711x_halt);
43
44 return cpuidle_register(drv: &clps711x_idle_driver, NULL);
45}
46
47static struct platform_driver clps711x_cpuidle_driver = {
48 .driver = {
49 .name = CLPS711X_CPUIDLE_NAME,
50 },
51};
52builtin_platform_driver_probe(clps711x_cpuidle_driver, clps711x_cpuidle_probe);
53

source code of linux/drivers/cpuidle/cpuidle-clps711x.c