12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
24ffd6952SAnton Vorontsov /*
34ffd6952SAnton Vorontsov * Suspend/resume support
44ffd6952SAnton Vorontsov *
54ffd6952SAnton Vorontsov * Copyright 2009 MontaVista Software, Inc.
64ffd6952SAnton Vorontsov *
74ffd6952SAnton Vorontsov * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
84ffd6952SAnton Vorontsov */
94ffd6952SAnton Vorontsov
104ffd6952SAnton Vorontsov #include <linux/init.h>
114ffd6952SAnton Vorontsov #include <linux/types.h>
124ffd6952SAnton Vorontsov #include <linux/errno.h>
1366b15db6SPaul Gortmaker #include <linux/export.h>
144ffd6952SAnton Vorontsov #include <linux/suspend.h>
154ffd6952SAnton Vorontsov #include <linux/delay.h>
16*81d7cac4SRob Herring #include <linux/mod_devicetable.h>
1726a2056eSRob Herring #include <linux/of_address.h>
18*81d7cac4SRob Herring #include <linux/platform_device.h>
194ffd6952SAnton Vorontsov
204ffd6952SAnton Vorontsov struct pmc_regs {
214ffd6952SAnton Vorontsov __be32 devdisr;
224ffd6952SAnton Vorontsov __be32 devdisr2;
234ffd6952SAnton Vorontsov __be32 :32;
244ffd6952SAnton Vorontsov __be32 :32;
254ffd6952SAnton Vorontsov __be32 pmcsr;
264ffd6952SAnton Vorontsov #define PMCSR_SLP (1 << 17)
274ffd6952SAnton Vorontsov };
284ffd6952SAnton Vorontsov
294ffd6952SAnton Vorontsov static struct device *pmc_dev;
304ffd6952SAnton Vorontsov static struct pmc_regs __iomem *pmc_regs;
314ffd6952SAnton Vorontsov
pmc_suspend_enter(suspend_state_t state)324ffd6952SAnton Vorontsov static int pmc_suspend_enter(suspend_state_t state)
334ffd6952SAnton Vorontsov {
344ffd6952SAnton Vorontsov int ret;
354ffd6952SAnton Vorontsov
364ffd6952SAnton Vorontsov setbits32(&pmc_regs->pmcsr, PMCSR_SLP);
374ffd6952SAnton Vorontsov /* At this point, the CPU is asleep. */
384ffd6952SAnton Vorontsov
394ffd6952SAnton Vorontsov /* Upon resume, wait for SLP bit to be clear. */
404ffd6952SAnton Vorontsov ret = spin_event_timeout((in_be32(&pmc_regs->pmcsr) & PMCSR_SLP) == 0,
414ffd6952SAnton Vorontsov 10000, 10) ? 0 : -ETIMEDOUT;
424ffd6952SAnton Vorontsov if (ret)
434ffd6952SAnton Vorontsov dev_err(pmc_dev, "tired waiting for SLP bit to clear\n");
444ffd6952SAnton Vorontsov return ret;
454ffd6952SAnton Vorontsov }
464ffd6952SAnton Vorontsov
pmc_suspend_valid(suspend_state_t state)474ffd6952SAnton Vorontsov static int pmc_suspend_valid(suspend_state_t state)
484ffd6952SAnton Vorontsov {
494ffd6952SAnton Vorontsov if (state != PM_SUSPEND_STANDBY)
504ffd6952SAnton Vorontsov return 0;
514ffd6952SAnton Vorontsov return 1;
524ffd6952SAnton Vorontsov }
534ffd6952SAnton Vorontsov
542f55ac07SLionel Debroux static const struct platform_suspend_ops pmc_suspend_ops = {
554ffd6952SAnton Vorontsov .valid = pmc_suspend_valid,
564ffd6952SAnton Vorontsov .enter = pmc_suspend_enter,
574ffd6952SAnton Vorontsov };
584ffd6952SAnton Vorontsov
pmc_probe(struct platform_device * ofdev)5900006124SGrant Likely static int pmc_probe(struct platform_device *ofdev)
604ffd6952SAnton Vorontsov {
6161c7a080SGrant Likely pmc_regs = of_iomap(ofdev->dev.of_node, 0);
624ffd6952SAnton Vorontsov if (!pmc_regs)
634ffd6952SAnton Vorontsov return -ENOMEM;
644ffd6952SAnton Vorontsov
654ffd6952SAnton Vorontsov pmc_dev = &ofdev->dev;
664ffd6952SAnton Vorontsov suspend_set_ops(&pmc_suspend_ops);
674ffd6952SAnton Vorontsov return 0;
684ffd6952SAnton Vorontsov }
694ffd6952SAnton Vorontsov
704ffd6952SAnton Vorontsov static const struct of_device_id pmc_ids[] = {
714ffd6952SAnton Vorontsov { .compatible = "fsl,mpc8548-pmc", },
724ffd6952SAnton Vorontsov { .compatible = "fsl,mpc8641d-pmc", },
734ffd6952SAnton Vorontsov { },
744ffd6952SAnton Vorontsov };
754ffd6952SAnton Vorontsov
7600006124SGrant Likely static struct platform_driver pmc_driver = {
774018294bSGrant Likely .driver = {
784018294bSGrant Likely .name = "fsl-pmc",
794018294bSGrant Likely .of_match_table = pmc_ids,
804018294bSGrant Likely },
814ffd6952SAnton Vorontsov .probe = pmc_probe,
824ffd6952SAnton Vorontsov };
834ffd6952SAnton Vorontsov
8416c6cb46SGeliang Tang builtin_platform_driver(pmc_driver);
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