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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Suspend/resume support
4 *
5 * Copyright 2009 MontaVista Software, Inc.
6 *
7 * Author: Anton Vorontsov <[email protected]>
8 */
9
10#include <linux/init.h>
11#include <linux/types.h>
12#include <linux/errno.h>
13#include <linux/export.h>
14#include <linux/suspend.h>
15#include <linux/delay.h>
16#include <linux/of_address.h>
17#include <linux/platform_device.h>
18
19struct pmc_regs {
20 __be32 devdisr;
21 __be32 devdisr2;
22 __be32 :32;
23 __be32 :32;
24 __be32 pmcsr;
25#define PMCSR_SLP (1 << 17)
26};
27
28static struct device *pmc_dev;
29static struct pmc_regs __iomem *pmc_regs;
30
31static int pmc_suspend_enter(suspend_state_t state)
32{
33 int ret;
34
35 setbits32(&pmc_regs->pmcsr, PMCSR_SLP);
36 /* At this point, the CPU is asleep. */
37
38 /* Upon resume, wait for SLP bit to be clear. */
39 ret = spin_event_timeout((in_be32(&pmc_regs->pmcsr) & PMCSR_SLP) == 0,
40 10000, 10) ? 0 : -ETIMEDOUT;
41 if (ret)
42 dev_err(pmc_dev, "tired waiting for SLP bit to clear\n");
43 return ret;
44}
45
46static int pmc_suspend_valid(suspend_state_t state)
47{
48 if (state != PM_SUSPEND_STANDBY)
49 return 0;
50 return 1;
51}
52
53static const struct platform_suspend_ops pmc_suspend_ops = {
54 .valid = pmc_suspend_valid,
55 .enter = pmc_suspend_enter,
56};
57
58static int pmc_probe(struct platform_device *ofdev)
59{
60 pmc_regs = of_iomap(ofdev->dev.of_node, 0);
61 if (!pmc_regs)
62 return -ENOMEM;
63
64 pmc_dev = &ofdev->dev;
65 suspend_set_ops(&pmc_suspend_ops);
66 return 0;
67}
68
69static const struct of_device_id pmc_ids[] = {
70 { .compatible = "fsl,mpc8548-pmc", },
71 { .compatible = "fsl,mpc8641d-pmc", },
72 { },
73};
74
75static struct platform_driver pmc_driver = {
76 .driver = {
77 .name = "fsl-pmc",
78 .of_match_table = pmc_ids,
79 },
80 .probe = pmc_probe,
81};
82
83builtin_platform_driver(pmc_driver);