xref: /openbmc/linux/drivers/clk/ingenic/pm.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2019 Paul Cercueil <paul@crapouillou.net>
4  */
5 
6 #include "cgu.h"
7 #include "pm.h"
8 
9 #include <linux/io.h>
10 #include <linux/syscore_ops.h>
11 
12 #define CGU_REG_LCR		0x04
13 
14 #define LCR_LOW_POWER_MODE	BIT(0)
15 
16 static void __iomem * __maybe_unused ingenic_cgu_base;
17 
18 static int __maybe_unused ingenic_cgu_pm_suspend(void)
19 {
20 	u32 val = readl(ingenic_cgu_base + CGU_REG_LCR);
21 
22 	writel(val | LCR_LOW_POWER_MODE, ingenic_cgu_base + CGU_REG_LCR);
23 
24 	return 0;
25 }
26 
27 static void __maybe_unused ingenic_cgu_pm_resume(void)
28 {
29 	u32 val = readl(ingenic_cgu_base + CGU_REG_LCR);
30 
31 	writel(val & ~LCR_LOW_POWER_MODE, ingenic_cgu_base + CGU_REG_LCR);
32 }
33 
34 static struct syscore_ops __maybe_unused ingenic_cgu_pm_ops = {
35 	.suspend = ingenic_cgu_pm_suspend,
36 	.resume = ingenic_cgu_pm_resume,
37 };
38 
39 void ingenic_cgu_register_syscore_ops(struct ingenic_cgu *cgu)
40 {
41 	if (IS_ENABLED(CONFIG_PM_SLEEP)) {
42 		ingenic_cgu_base = cgu->base;
43 		register_syscore_ops(&ingenic_cgu_pm_ops);
44 	}
45 }
46