// SPDX-License-Identifier: GPL-2.0
/*
 * Intel PCH pinctrl/GPIO driver
 *
 * Copyright (C) 2021-2023 Intel Corporation
 * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
 */

#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/property.h>
#include <linux/string_helpers.h>

#include <linux/pinctrl/pinctrl.h>

#include "pinctrl-intel.h"

struct intel_platform_pins {
        struct pinctrl_pin_desc *pins;
        size_t npins;
};

static int intel_platform_pinctrl_prepare_pins(struct device *dev, size_t base,
                                               const char *name, u32 size,
                                               struct intel_platform_pins *pins)
{
        struct pinctrl_pin_desc *descs;
        char **pin_names;
        unsigned int i;

        pin_names = devm_kasprintf_strarray(dev, name, size);
        if (IS_ERR(pin_names))
                return PTR_ERR(pin_names);

        descs = devm_krealloc_array(dev, pins->pins, base + size, sizeof(*descs), GFP_KERNEL);
        if (!descs)
                return -ENOMEM;

        for (i = 0; i < size; i++) {
                unsigned int pin_number = base + i;
                char *pin_name = pin_names[i];
                struct pinctrl_pin_desc *desc;

                /* Unify delimiter for pin name */
                strreplace(pin_name, '-', '_');

                desc = &descs[pin_number];
                desc->number = pin_number;
                desc->name = pin_name;
        }

        pins->pins = descs;
        pins->npins = base + size;

        return 0;
}

static int intel_platform_pinctrl_prepare_group(struct device *dev,
                                                struct fwnode_handle *child,
                                                struct intel_padgroup *gpp,
                                                struct intel_platform_pins *pins)
{
        size_t base = pins->npins;
        const char *name;
        u32 size;
        int ret;

        ret = fwnode_property_read_string(child, "intc-gpio-group-name", &name);
        if (ret)
                return ret;

        ret = fwnode_property_read_u32(child, "intc-gpio-pad-count", &size);
        if (ret)
                return ret;

        ret = intel_platform_pinctrl_prepare_pins(dev, base, name, size, pins);
        if (ret)
                return ret;

        gpp->base = base;
        gpp->size = size;
        gpp->gpio_base = INTEL_GPIO_BASE_MATCH;

        return 0;
}

static int intel_platform_pinctrl_prepare_community(struct device *dev,
                                                    struct intel_community *community,
                                                    struct intel_platform_pins *pins)
{
        struct intel_padgroup *gpps;
        unsigned int group;
        size_t ngpps;
        u32 offset;
        int ret;

        ret = device_property_read_u32(dev, "intc-gpio-pad-ownership-offset", &offset);
        if (ret)
                return ret;
        community->padown_offset = offset;

        ret = device_property_read_u32(dev, "intc-gpio-pad-configuration-lock-offset", &offset);
        if (ret)
                return ret;
        community->padcfglock_offset = offset;

        ret = device_property_read_u32(dev, "intc-gpio-host-software-pad-ownership-offset", &offset);
        if (ret)
                return ret;
        community->hostown_offset = offset;

        ret = device_property_read_u32(dev, "intc-gpio-gpi-interrupt-status-offset", &offset);
        if (ret)
                return ret;
        community->is_offset = offset;

        ret = device_property_read_u32(dev, "intc-gpio-gpi-interrupt-enable-offset", &offset);
        if (ret)
                return ret;
        community->ie_offset = offset;

        ngpps = device_get_child_node_count(dev);
        if (!ngpps)
                return -ENODEV;

        gpps = devm_kcalloc(dev, ngpps, sizeof(*gpps), GFP_KERNEL);
        if (!gpps)
                return -ENOMEM;

        group = 0;
        device_for_each_child_node_scoped(dev, child) {
                struct intel_padgroup *gpp = &gpps[group];

                gpp->reg_num = group;

                ret = intel_platform_pinctrl_prepare_group(dev, child, gpp, pins);
                if (ret)
                        return ret;

                group++;
        }

        community->ngpps = ngpps;
        community->gpps = gpps;

        return 0;
}

static int intel_platform_pinctrl_prepare_soc_data(struct device *dev,
                                                   struct intel_pinctrl_soc_data *data)
{
        struct intel_platform_pins pins = {};
        struct intel_community *communities;
        size_t ncommunities;
        unsigned int i;
        int ret;

        /* Version 1.0 of the specification assumes only a single community per device node */
        ncommunities = 1;
        communities = devm_kcalloc(dev, ncommunities, sizeof(*communities), GFP_KERNEL);
        if (!communities)
                return -ENOMEM;

        for (i = 0; i < ncommunities; i++) {
                struct intel_community *community = &communities[i];

                community->barno = i;
                community->pin_base = pins.npins;

                ret = intel_platform_pinctrl_prepare_community(dev, community, &pins);
                if (ret)
                        return ret;

                community->npins = pins.npins - community->pin_base;
        }

        data->ncommunities = ncommunities;
        data->communities = communities;

        data->npins = pins.npins;
        data->pins = pins.pins;

        return 0;
}

static int intel_platform_pinctrl_probe(struct platform_device *pdev)
{
        struct intel_pinctrl_soc_data *data;
        struct device *dev = &pdev->dev;
        int ret;

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

        ret = intel_platform_pinctrl_prepare_soc_data(dev, data);
        if (ret)
                return ret;

        return intel_pinctrl_probe(pdev, data);
}

static const struct acpi_device_id intel_platform_pinctrl_acpi_match[] = {
        { "INTC105F" },
        { }
};
MODULE_DEVICE_TABLE(acpi, intel_platform_pinctrl_acpi_match);

static struct platform_driver intel_platform_pinctrl_driver = {
        .probe = intel_platform_pinctrl_probe,
        .driver = {
                .name = "intel-pinctrl",
                .acpi_match_table = intel_platform_pinctrl_acpi_match,
                .pm = pm_sleep_ptr(&intel_pinctrl_pm_ops),
        },
};
module_platform_driver(intel_platform_pinctrl_driver);

MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
MODULE_DESCRIPTION("Intel PCH pinctrl/GPIO driver");
MODULE_LICENSE("GPL v2");
MODULE_IMPORT_NS("PINCTRL_INTEL");