// SPDX-License-Identifier: GPL-2.0+
/*
 * (C) Copyright 2016 - Beniamino Galvani <b.galvani@gmail.com>
 */

#include <log.h>
#include <asm/gpio.h>
#include <common.h>
#include <dm.h>
#include <dm/pinctrl.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include "pinctrl-meson-gx.h"

static void meson_gx_pinmux_disable_other_groups(struct meson_pinctrl *priv,
                                                 unsigned int pin,
                                                 int sel_group)
{
        struct meson_pmx_group *group;
        struct meson_gx_pmx_data *pmx_data;
        void __iomem *addr;
        int i, j;

        for (i = 0; i < priv->data->num_groups; i++) {
                group = &priv->data->groups[i];
                pmx_data = (struct meson_gx_pmx_data *)group->data;
                if (pmx_data->is_gpio || i == sel_group)
                        continue;

                for (j = 0; j < group->num_pins; j++) {
                        if (group->pins[j] == pin) {
                                /* We have found a group using the pin */
                                debug("pinmux: disabling %s\n", group->name);
                                addr = priv->reg_mux + pmx_data->reg * 4;
                                writel(readl(addr) & ~BIT(pmx_data->bit), addr);
                        }
                }
        }
}

static int meson_gx_pinmux_group_set(struct udevice *dev,
                                     unsigned int group_selector,
                                     unsigned int func_selector)
{
        struct meson_pinctrl *priv = dev_get_priv(dev);
        const struct meson_pmx_group *group;
        const struct meson_pmx_func *func;
        struct meson_gx_pmx_data *pmx_data;
        void __iomem *addr;
        int i;

        group = &priv->data->groups[group_selector];
        pmx_data = (struct meson_gx_pmx_data *)group->data;
        func = &priv->data->funcs[func_selector];

        debug("pinmux: set group %s func %s\n", group->name, func->name);

        /*
         * Disable groups using the same pins.
         * The selected group is not disabled to avoid glitches.
         */
        for (i = 0; i < group->num_pins; i++) {
                meson_gx_pinmux_disable_other_groups(priv,
                                                     group->pins[i],
                                                     group_selector);
        }

        /* Function 0 (GPIO) doesn't need any additional setting */
        if (func_selector) {
                addr = priv->reg_mux + pmx_data->reg * 4;
                writel(readl(addr) | BIT(pmx_data->bit), addr);
        }

        return 0;
}

static int meson_gx_pinmux_get(struct udevice *dev,
                                      unsigned int selector,
                                      char *buf, int size)
{
        struct meson_pinctrl *priv = dev_get_priv(dev);
        struct meson_pmx_group *group;
        struct meson_gx_pmx_data *pmx_data;
        void __iomem *addr;
        int i, j, pos = 0;
        unsigned int pin;
        u32 reg;

        pin = selector + priv->data->pin_base;

        for (i = 0; i < priv->data->num_groups; i++) {
                group = &priv->data->groups[i];
                pmx_data = (struct meson_gx_pmx_data *)group->data;
                if (pmx_data->is_gpio)
                        continue;

                for (j = 0; j < group->num_pins; j++) {
                        if (group->pins[j] == pin) {
                                /* We have found a group using the pin */
                                addr = priv->reg_mux + pmx_data->reg * 4;
                                reg = readl(addr) & BIT(pmx_data->bit);
                                if (reg) {
                                        pos += snprintf(buf + pos, size - pos,
                                                        "%s ", group->name) - 1;
                                        return 0;
                                }
                        }
                }
        }

        /* Fallback, must be used as GPIO */
        snprintf(buf, size, "%s or Unknown",
                 priv->data->groups[selector].name);

        return 0;
}

const struct pinconf_param meson_gx_pinconf_params[] = {
        { "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 },
        { "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 },
        { "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 },
};

const struct pinctrl_ops meson_gx_pinctrl_ops = {
        .get_groups_count = meson_pinctrl_get_groups_count,
        .get_group_name = meson_pinctrl_get_group_name,
        .get_functions_count = meson_pinmux_get_functions_count,
        .get_function_name = meson_pinmux_get_function_name,
        .pinmux_group_set = meson_gx_pinmux_group_set,
        .set_state = pinctrl_generic_set_state,
        .pinconf_params = meson_gx_pinconf_params,
        .pinconf_num_params = ARRAY_SIZE(meson_gx_pinconf_params),
        .pinconf_set = meson_pinconf_set,
        .pinconf_group_set = meson_pinconf_group_set,
        .get_pin_name = meson_pinctrl_get_pin_name,
        .get_pins_count = meson_pinctrl_get_pins_count,
        .get_pin_muxing = meson_gx_pinmux_get,
};

static const struct dm_gpio_ops meson_gx_gpio_ops = {
        .set_value = meson_gpio_set,
        .get_value = meson_gpio_get,
        .get_function = meson_gpio_get_direction,
        .direction_input = meson_gpio_direction_input,
        .direction_output = meson_gpio_direction_output,
};

const struct driver meson_gx_gpio_driver = {
        .name   = "meson-gx-gpio",
        .id     = UCLASS_GPIO,
        .probe  = meson_gpio_probe,
        .ops    = &meson_gx_gpio_ops,
};