// SPDX-License-Identifier: GPL-2.0+
/*
 * PM MFD driver for Broadcom BCM2835
 *
 * This driver binds to the PM block and creates the MFD device for
 * the WDT and power drivers.
 */

#include <linux/delay.h>
#include <linux/io.h>
#include <linux/mfd/bcm2835-pm.h>
#include <linux/mfd/core.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/types.h>
#include <linux/watchdog.h>

static const struct mfd_cell bcm2835_pm_devs[] = {
        { .name = "bcm2835-wdt" },
};

static const struct mfd_cell bcm2835_power_devs[] = {
        { .name = "bcm2835-power" },
};

static int bcm2835_pm_get_pdata(struct platform_device *pdev,
                                struct bcm2835_pm *pm)
{
        if (of_property_present(pm->dev->of_node, "reg-names")) {
                struct resource *res;

                pm->base = devm_platform_ioremap_resource_byname(pdev, "pm");
                if (IS_ERR(pm->base))
                        return PTR_ERR(pm->base);

                res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "asb");
                if (res) {
                        pm->asb = devm_ioremap_resource(&pdev->dev, res);
                        if (IS_ERR(pm->asb))
                                pm->asb = NULL;
                }

                res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
                                                    "rpivid_asb");
                if (res) {
                        pm->rpivid_asb = devm_ioremap_resource(&pdev->dev, res);
                        if (IS_ERR(pm->rpivid_asb))
                                pm->rpivid_asb = NULL;
                }

                return 0;
        }

        /* If no 'reg-names' property is found we can assume we're using old DTB. */
        pm->base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(pm->base))
                return PTR_ERR(pm->base);

        pm->asb = devm_platform_ioremap_resource(pdev, 1);
        if (IS_ERR(pm->asb))
                pm->asb = NULL;

        pm->rpivid_asb = devm_platform_ioremap_resource(pdev, 2);
        if (IS_ERR(pm->rpivid_asb))
                pm->rpivid_asb = NULL;

        return 0;
}

static int bcm2835_pm_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct bcm2835_pm *pm;
        int ret;

        pm = devm_kzalloc(dev, sizeof(*pm), GFP_KERNEL);
        if (!pm)
                return -ENOMEM;
        platform_set_drvdata(pdev, pm);

        pm->dev = dev;

        ret = bcm2835_pm_get_pdata(pdev, pm);
        if (ret)
                return ret;

        ret = devm_mfd_add_devices(dev, -1,
                                   bcm2835_pm_devs, ARRAY_SIZE(bcm2835_pm_devs),
                                   NULL, 0, NULL);
        if (ret)
                return ret;

        /*
         * We'll use the presence of the AXI ASB regs in the
         * bcm2835-pm binding as the key for whether we can reference
         * the full PM register range and support power domains.
         */
        if (pm->asb)
                return devm_mfd_add_devices(dev, -1, bcm2835_power_devs,
                                            ARRAY_SIZE(bcm2835_power_devs),
                                            NULL, 0, NULL);
        return 0;
}

static const struct of_device_id bcm2835_pm_of_match[] = {
        { .compatible = "brcm,bcm2835-pm-wdt", },
        { .compatible = "brcm,bcm2835-pm", },
        { .compatible = "brcm,bcm2711-pm", },
        { .compatible = "brcm,bcm2712-pm", },
        {},
};
MODULE_DEVICE_TABLE(of, bcm2835_pm_of_match);

static struct platform_driver bcm2835_pm_driver = {
        .probe          = bcm2835_pm_probe,
        .driver = {
                .name = "bcm2835-pm",
                .of_match_table = bcm2835_pm_of_match,
        },
};
module_platform_driver(bcm2835_pm_driver);

MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
MODULE_DESCRIPTION("Driver for Broadcom BCM2835 PM MFD");