// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2024 Linaro Ltd.
 */

#include <linux/device.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/pci-pwrctrl.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/pwrseq/consumer.h>
#include <linux/slab.h>
#include <linux/types.h>

struct pwrseq_pwrctrl {
        struct pci_pwrctrl pwrctrl;
        struct pwrseq_desc *pwrseq;
};

struct pwrseq_pwrctrl_pdata {
        const char *target;
        /*
         * Called before doing anything else to perform device-specific
         * verification between requesting the power sequencing handle.
         */
        int (*validate_device)(struct device *dev);
};

static int pwrseq_pwrctrl_qcm_wcn_validate_device(struct device *dev)
{
        /*
         * Old device trees for some platforms already define wifi nodes for
         * the WCN family of chips since before power sequencing was added
         * upstream.
         *
         * These nodes don't consume the regulator outputs from the PMU, and
         * if we allow this driver to bind to one of such "incomplete" nodes,
         * we'll see a kernel log error about the indefinite probe deferral.
         *
         * Check the existence of the regulator supply that exists on all
         * WCN models before moving forward.
         */
        if (!device_property_present(dev, "vddaon-supply"))
                return -ENODEV;

        return 0;
}

static const struct pwrseq_pwrctrl_pdata pwrseq_pwrctrl_qcom_wcn_pdata = {
        .target = "wlan",
        .validate_device = pwrseq_pwrctrl_qcm_wcn_validate_device,
};

static int pwrseq_pwrctrl_power_on(struct pci_pwrctrl *pwrctrl)
{
        struct pwrseq_pwrctrl *pwrseq = container_of(pwrctrl,
                                           struct pwrseq_pwrctrl, pwrctrl);

        return pwrseq_power_on(pwrseq->pwrseq);
}

static int pwrseq_pwrctrl_power_off(struct pci_pwrctrl *pwrctrl)
{
        struct pwrseq_pwrctrl *pwrseq = container_of(pwrctrl,
                                           struct pwrseq_pwrctrl, pwrctrl);

        return pwrseq_power_off(pwrseq->pwrseq);
}

static int pwrseq_pwrctrl_probe(struct platform_device *pdev)
{
        const struct pwrseq_pwrctrl_pdata *pdata;
        struct pwrseq_pwrctrl *pwrseq;
        struct device *dev = &pdev->dev;
        int ret;

        pdata = device_get_match_data(dev);
        if (!pdata || !pdata->target)
                return -EINVAL;

        if (pdata->validate_device) {
                ret = pdata->validate_device(dev);
                if (ret)
                        return ret;
        }

        pwrseq = devm_kzalloc(dev, sizeof(*pwrseq), GFP_KERNEL);
        if (!pwrseq)
                return -ENOMEM;

        pwrseq->pwrseq = devm_pwrseq_get(dev, pdata->target);
        if (IS_ERR(pwrseq->pwrseq))
                return dev_err_probe(dev, PTR_ERR(pwrseq->pwrseq),
                                     "Failed to get the power sequencer\n");

        pwrseq->pwrctrl.power_on = pwrseq_pwrctrl_power_on;
        pwrseq->pwrctrl.power_off = pwrseq_pwrctrl_power_off;

        pci_pwrctrl_init(&pwrseq->pwrctrl, dev);

        ret = devm_pci_pwrctrl_device_set_ready(dev, &pwrseq->pwrctrl);
        if (ret)
                return dev_err_probe(dev, ret,
                                     "Failed to register the pwrctrl wrapper\n");

        return 0;
}

static const struct of_device_id pwrseq_pwrctrl_of_match[] = {
        {
                /* ATH11K in QCA6390 package. */
                .compatible = "pci17cb,1101",
                .data = &pwrseq_pwrctrl_qcom_wcn_pdata,
        },
        {
                /* ATH11K in WCN6855 package. */
                .compatible = "pci17cb,1103",
                .data = &pwrseq_pwrctrl_qcom_wcn_pdata,
        },
        {
                /* ATH12K in WCN7850 package. */
                .compatible = "pci17cb,1107",
                .data = &pwrseq_pwrctrl_qcom_wcn_pdata,
        },
        { }
};
MODULE_DEVICE_TABLE(of, pwrseq_pwrctrl_of_match);

static struct platform_driver pwrseq_pwrctrl_driver = {
        .driver = {
                .name = "pci-pwrctrl-pwrseq",
                .of_match_table = pwrseq_pwrctrl_of_match,
        },
        .probe = pwrseq_pwrctrl_probe,
};
module_platform_driver(pwrseq_pwrctrl_driver);

MODULE_AUTHOR("Bartosz Golaszewski <bartosz.golaszewski@linaro.org>");
MODULE_DESCRIPTION("Generic PCI Power Control module for power sequenced devices");
MODULE_LICENSE("GPL");