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
16 static void __iomem *clps711x_halt;
17
clps711x_cpuidle_halt(struct cpuidle_device * dev,struct cpuidle_driver * drv,int index)18 static int clps711x_cpuidle_halt(struct cpuidle_device *dev,
19 struct cpuidle_driver *drv, int index)
20 {
21 writel(0xaa, clps711x_halt);
22
23 return index;
24 }
25
26 static 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
clps711x_cpuidle_probe(struct platform_device * pdev)38 static int __init clps711x_cpuidle_probe(struct platform_device *pdev)
39 {
40 clps711x_halt = devm_platform_ioremap_resource(pdev, 0);
41 if (IS_ERR(clps711x_halt))
42 return PTR_ERR(clps711x_halt);
43
44 return cpuidle_register(&clps711x_idle_driver, NULL);
45 }
46
47 static struct platform_driver clps711x_cpuidle_driver = {
48 .driver = {
49 .name = CLPS711X_CPUIDLE_NAME,
50 },
51 };
52 builtin_platform_driver_probe(clps711x_cpuidle_driver, clps711x_cpuidle_probe);
53