/*
 * Copyright 2019 Emmanuel Vadot <manu@freebsd.org>
 * Copyright (c) 2017 Ian Lepore <ian@freebsd.org> All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/gpio.h>
#include <sys/taskqueue.h>

#include <dev/mmc/bridge.h>
#include <dev/mmc/mmc_fdt_helpers.h>

#include <dev/gpio/gpiobusvar.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

#include <dev/regulator/regulator.h>

#include <dev/mmc/mmc_helpers.h>

#include "mmc_pwrseq_if.h"

int
mmc_fdt_parse(device_t dev, phandle_t node, struct mmc_helper *helper,
    struct mmc_host *host)
{
        struct mmc_helper mmc_helper;
        phandle_t pwrseq_xref;

        memset(&mmc_helper, 0, sizeof(mmc_helper));
        mmc_parse(dev, &mmc_helper, host);

        helper->props = mmc_helper.props;

        /*
         * Get the regulators if they are supported and
         * clean the non supported modes based on the available voltages.
         */
        if (regulator_get_by_ofw_property(dev, 0, "vmmc-supply",
            &helper->vmmc_supply) == 0) {
                if (bootverbose)
                        device_printf(dev, "vmmc-supply regulator found\n");
        }
        if (regulator_get_by_ofw_property(dev, 0, "vqmmc-supply",
            &helper->vqmmc_supply) == 0) {
                if (bootverbose)
                        device_printf(dev, "vqmmc-supply regulator found\n");
        }

        if (helper->vqmmc_supply != NULL) {
                if (regulator_check_voltage(helper->vqmmc_supply, 1200000) == 0)
                        host->caps |= MMC_CAP_SIGNALING_120;
                else
                        host->caps &= ~( MMC_CAP_MMC_HS400_120 |
                            MMC_CAP_MMC_HS200_120 |
                            MMC_CAP_MMC_DDR52_120);
                if (regulator_check_voltage(helper->vqmmc_supply, 1800000) == 0)
                        host->caps |= MMC_CAP_SIGNALING_180;
                else
                        host->caps &= ~(MMC_CAP_MMC_HS400_180 |
                            MMC_CAP_MMC_HS200_180 |
                            MMC_CAP_MMC_DDR52_180 |
                            MMC_CAP_UHS_DDR50 |
                            MMC_CAP_UHS_SDR104 |
                            MMC_CAP_UHS_SDR50 |
                            MMC_CAP_UHS_SDR25);
                if (regulator_check_voltage(helper->vqmmc_supply, 3300000) == 0)
                        host->caps |= MMC_CAP_SIGNALING_330;
        } else
                host->caps |= MMC_CAP_SIGNALING_330;

        if (OF_hasprop(node, "mmc-pwrseq")) {
                if (OF_getencprop(node, "mmc-pwrseq", &pwrseq_xref, sizeof(pwrseq_xref)) == -1) {
                        device_printf(dev, "Cannot get the pwrseq_xref property\n");
                        return (ENXIO);
                }
                helper->mmc_pwrseq = OF_device_from_xref(pwrseq_xref);
        }
        return (0);
}

/*
 * Card detect interrupt handler.
 */
static void
cd_intr(void *arg)
{
        struct mmc_helper *helper = arg;

        taskqueue_enqueue_timeout(taskqueue_bus,
            &helper->cd_delayed_task, -(hz / 2));
}

static void
cd_card_task(void *arg, int pending __unused)
{
        struct mmc_helper *helper = arg;
        bool cd_present;

        cd_present = mmc_fdt_gpio_get_present(helper);
        if(helper->cd_handler && cd_present != helper->cd_present)
                helper->cd_handler(helper->dev,
                    cd_present);
        helper->cd_present = cd_present;

        /* If we're polling re-schedule the task */
        if (helper->cd_ihandler == NULL)
                taskqueue_enqueue_timeout_sbt(taskqueue_bus,
                    &helper->cd_delayed_task, mstosbt(500), 0, C_PREL(2));
}

/*
 * Card detect setup.
 */
static void
cd_setup(struct mmc_helper *helper, phandle_t node)
{
        int pincaps;
        device_t dev;
        const char *cd_mode_str;

        dev = helper->dev;

        TIMEOUT_TASK_INIT(taskqueue_bus, &helper->cd_delayed_task, 0,
            cd_card_task, helper);

        /*
         * If the device is flagged as non-removable, set that slot option, and
         * set a flag to make sdhci_fdt_gpio_get_present() always return true.
         */
        if (helper->props & MMC_PROP_NON_REMOVABLE) {
                helper->cd_disabled = true;
                if (bootverbose)
                        device_printf(dev, "Non-removable media\n");
                return;
        }

        /*
         * If the device has no card-detection, treat it as non-removable.
         * This could be improved by polling for detection.
         */
        if (helper->props & MMC_PROP_BROKEN_CD) {
                helper->cd_disabled = true;
                if (bootverbose)
                        device_printf(dev, "Broken card-detect\n");
                return;
        }

        /*
         * If there is no cd-gpios property, then presumably the hardware
         * PRESENT_STATE register and interrupts will reflect card state
         * properly, and there's nothing more for us to do.  Our get_present()
         * will return sdhci_generic_get_card_present() because cd_pin is NULL.
         *
         * If there is a property, make sure we can read the pin.
         */
        if (gpio_pin_get_by_ofw_property(dev, node, "cd-gpios",
            &helper->cd_pin))
                return;

        if (gpio_pin_getcaps(helper->cd_pin, &pincaps) != 0 ||
            !(pincaps & GPIO_PIN_INPUT)) {
                device_printf(dev, "Cannot read card-detect gpio pin; "
                    "setting card-always-present flag.\n");
                helper->cd_disabled = true;
                return;
        }

        /*
         * If the pin can trigger an interrupt on both rising and falling edges,
         * we can use it to detect card presence changes.  If not, we'll request
         * card presence polling instead of using interrupts.
         */
        if (!(pincaps & GPIO_INTR_EDGE_BOTH)) {
                if (bootverbose)
                        device_printf(dev, "Cannot configure "
                            "GPIO_INTR_EDGE_BOTH for card detect\n");
                goto without_interrupts;
        }

        if (helper->cd_handler == NULL) {
                if (bootverbose)
                        device_printf(dev, "Cannot configure "
                            "interrupts as no cd_handler is set\n");
                goto without_interrupts;
        }

        /*
         * Create an interrupt resource from the pin and set up the interrupt.
         */
        if ((helper->cd_ires = gpio_alloc_intr_resource(dev, helper->cd_irid,
            RF_ACTIVE, helper->cd_pin, GPIO_INTR_EDGE_BOTH)) == NULL) {
                if (bootverbose)
                        device_printf(dev, "Cannot allocate an IRQ for card "
                            "detect GPIO\n");
                goto without_interrupts;
        }

        if (bus_setup_intr(dev, helper->cd_ires, INTR_TYPE_BIO | INTR_MPSAFE,
            NULL, cd_intr, helper, &helper->cd_ihandler) != 0) {
                device_printf(dev, "Unable to setup card-detect irq handler\n");
                helper->cd_ihandler = NULL;
                goto without_interrupts;
        }

without_interrupts:
        /*
         * If we have a readable gpio pin, but didn't successfully configure
         * gpio interrupts, setup a timeout task to poll the pin
         */
        if (helper->cd_ihandler == NULL) {
                cd_mode_str = "polling";
        } else {
                cd_mode_str = "interrupts";
        }

        if (bootverbose) {
                device_printf(dev, "Card presence detect on %s pin %u, "
                    "configured for %s.\n",
                    device_get_nameunit(helper->cd_pin->dev), helper->cd_pin->pin,
                    cd_mode_str);
        }
}

/*
 * Write protect setup.
 */
static void
wp_setup(struct mmc_helper *helper, phandle_t node)
{
        device_t dev;

        dev = helper->dev;

        if (OF_hasprop(node, "disable-wp")) {
                helper->wp_disabled = true;
                if (bootverbose)
                        device_printf(dev, "Write protect disabled\n");
                return;
        }

        if (gpio_pin_get_by_ofw_property(dev, node, "wp-gpios", &helper->wp_pin))
                return;

        if (bootverbose)
                device_printf(dev, "Write protect switch on %s pin %u\n",
                    device_get_nameunit(helper->wp_pin->dev), helper->wp_pin->pin);
}

int
mmc_fdt_gpio_setup(device_t dev, phandle_t node, struct mmc_helper *helper,
    mmc_fdt_cd_handler handler)
{

        if (node <= 0)
                node = ofw_bus_get_node(dev);
        if (node <= 0) {
                device_printf(dev, "Cannot get node for device\n");
                return (ENXIO);
        }

        helper->dev = dev;
        helper->cd_handler = handler;
        cd_setup(helper, node);
        wp_setup(helper, node);

        /* 
         * Schedule a card detection
         */
        taskqueue_enqueue_timeout_sbt(taskqueue_bus,
            &helper->cd_delayed_task, mstosbt(500), 0, C_PREL(2));
        return (0);
}

void
mmc_fdt_gpio_teardown(struct mmc_helper *helper)
{

        if (helper == NULL)
                return;

        if (helper->cd_ihandler != NULL)
                bus_teardown_intr(helper->dev, helper->cd_ires, helper->cd_ihandler);
        if (helper->wp_pin != NULL)
                gpio_pin_release(helper->wp_pin);
        if (helper->cd_pin != NULL)
                gpio_pin_release(helper->cd_pin);
        if (helper->cd_ires != NULL)
                bus_release_resource(helper->dev, SYS_RES_IRQ, 0, helper->cd_ires);

        taskqueue_drain_timeout(taskqueue_bus, &helper->cd_delayed_task);
}

bool
mmc_fdt_gpio_get_present(struct mmc_helper *helper)
{
        bool pinstate;

        if (helper->cd_disabled)
                return (true);
        if (helper->cd_pin == NULL)
                return (false);

        gpio_pin_is_active(helper->cd_pin, &pinstate);

        return (pinstate ^ (bool)(helper->props & MMC_PROP_CD_INVERTED));
}

bool
mmc_fdt_gpio_get_readonly(struct mmc_helper *helper)
{
        bool pinstate;

        if (helper->wp_disabled)
                return (false);

        if (helper->wp_pin == NULL)
                return (false);

        gpio_pin_is_active(helper->wp_pin, &pinstate);

        return (pinstate ^ (bool)(helper->props & MMC_PROP_WP_INVERTED));
}

void
mmc_fdt_set_power(struct mmc_helper *helper, enum mmc_power_mode power_mode)
{
        int reg_status;
        int rv;

        switch (power_mode) {
        case power_on:
                break;
        case power_off:
                if (helper->vmmc_supply) {
                        rv = regulator_status(helper->vmmc_supply, &reg_status);
                        if (rv == 0 && reg_status == REGULATOR_STATUS_ENABLED)
                                regulator_disable(helper->vmmc_supply);
                }
                if (helper->vqmmc_supply) {
                        rv = regulator_status(helper->vqmmc_supply, &reg_status);
                        if (rv == 0 && reg_status == REGULATOR_STATUS_ENABLED)
                                regulator_disable(helper->vqmmc_supply);
                }
                if (helper->mmc_pwrseq)
                        MMC_PWRSEQ_SET_POWER(helper->mmc_pwrseq, false);
                break;
        case power_up:
                if (helper->vmmc_supply) {
                        rv = regulator_status(helper->vmmc_supply, &reg_status);
                        if (rv == 0 && reg_status != REGULATOR_STATUS_ENABLED)
                                regulator_enable(helper->vmmc_supply);
                }
                if (helper->vqmmc_supply) {
                        rv = regulator_status(helper->vqmmc_supply, &reg_status);
                        if (rv == 0 && reg_status != REGULATOR_STATUS_ENABLED)
                                regulator_enable(helper->vqmmc_supply);
                }
                if (helper->mmc_pwrseq)
                        MMC_PWRSEQ_SET_POWER(helper->mmc_pwrseq, true);
                break;
        }
}