// SPDX-License-Identifier: GPL-2.0-only
/*
 *  linux/drivers/mmc/core/host.c
 *
 *  Copyright (C) 2003 Russell King, All Rights Reserved.
 *  Copyright (C) 2007-2008 Pierre Ossman
 *  Copyright (C) 2010 Linus Walleij
 *
 *  MMC host class device management
 */

#include <linux/device.h>
#include <linux/err.h>
#include <linux/idr.h>
#include <linux/of.h>
#include <linux/pagemap.h>
#include <linux/export.h>
#include <linux/leds.h>
#include <linux/slab.h>

#include <linux/mmc/host.h>
#include <linux/mmc/card.h>
#include <linux/mmc/slot-gpio.h>

#include "core.h"
#include "crypto.h"
#include "host.h"
#include "slot-gpio.h"
#include "pwrseq.h"
#include "sdio_ops.h"

#define cls_dev_to_mmc_host(d)  container_of(d, struct mmc_host, class_dev)

static DEFINE_IDA(mmc_host_ida);

#ifdef CONFIG_PM_SLEEP
static int mmc_host_class_prepare(struct device *dev)
{
        struct mmc_host *host = cls_dev_to_mmc_host(dev);

        /*
         * It's safe to access the bus_ops pointer, as both userspace and the
         * workqueue for detecting cards are frozen at this point.
         */
        if (!host->bus_ops)
                return 0;

        /* Validate conditions for system suspend. */
        if (host->bus_ops->pre_suspend)
                return host->bus_ops->pre_suspend(host);

        return 0;
}

static void mmc_host_class_complete(struct device *dev)
{
        struct mmc_host *host = cls_dev_to_mmc_host(dev);

        _mmc_detect_change(host, 0, false);
}

static const struct dev_pm_ops mmc_host_class_dev_pm_ops = {
        .prepare = mmc_host_class_prepare,
        .complete = mmc_host_class_complete,
};

#define MMC_HOST_CLASS_DEV_PM_OPS (&mmc_host_class_dev_pm_ops)
#else
#define MMC_HOST_CLASS_DEV_PM_OPS NULL
#endif

static void mmc_host_classdev_release(struct device *dev)
{
        struct mmc_host *host = cls_dev_to_mmc_host(dev);
        wakeup_source_unregister(host->ws);
        if (of_alias_get_id(host->parent->of_node, "mmc") < 0)
                ida_free(&mmc_host_ida, host->index);
        kfree(host);
}

static int mmc_host_classdev_shutdown(struct device *dev)
{
        struct mmc_host *host = cls_dev_to_mmc_host(dev);

        __mmc_stop_host(host);
        return 0;
}

static const struct class mmc_host_class = {
        .name           = "mmc_host",
        .dev_release    = mmc_host_classdev_release,
        .shutdown_pre   = mmc_host_classdev_shutdown,
        .pm             = MMC_HOST_CLASS_DEV_PM_OPS,
};

int mmc_register_host_class(void)
{
        return class_register(&mmc_host_class);
}

void mmc_unregister_host_class(void)
{
        class_unregister(&mmc_host_class);
}

/**
 * mmc_retune_enable() - enter a transfer mode that requires retuning
 * @host: host which should retune now
 */
void mmc_retune_enable(struct mmc_host *host)
{
        host->can_retune = 1;
        if (host->retune_period)
                mod_timer(&host->retune_timer,
                          jiffies + host->retune_period * HZ);
}

/*
 * Pause re-tuning for a small set of operations.  The pause begins after the
 * next command.
 */
void mmc_retune_pause(struct mmc_host *host)
{
        if (!host->retune_paused) {
                host->retune_paused = 1;
                mmc_retune_hold(host);
        }
}
EXPORT_SYMBOL(mmc_retune_pause);

void mmc_retune_unpause(struct mmc_host *host)
{
        if (host->retune_paused) {
                host->retune_paused = 0;
                mmc_retune_release(host);
        }
}
EXPORT_SYMBOL(mmc_retune_unpause);

/**
 * mmc_retune_disable() - exit a transfer mode that requires retuning
 * @host: host which should not retune anymore
 *
 * It is not meant for temporarily preventing retuning!
 */
void mmc_retune_disable(struct mmc_host *host)
{
        mmc_retune_unpause(host);
        host->can_retune = 0;
        timer_delete_sync(&host->retune_timer);
        mmc_retune_clear(host);
}

void mmc_retune_timer_stop(struct mmc_host *host)
{
        timer_delete_sync(&host->retune_timer);
}
EXPORT_SYMBOL(mmc_retune_timer_stop);

void mmc_retune_hold(struct mmc_host *host)
{
        if (!host->hold_retune)
                host->retune_now = 1;
        host->hold_retune += 1;
}

void mmc_retune_release(struct mmc_host *host)
{
        if (host->hold_retune)
                host->hold_retune -= 1;
        else
                WARN_ON(1);
}
EXPORT_SYMBOL(mmc_retune_release);

int mmc_retune(struct mmc_host *host)
{
        bool return_to_hs400 = false;
        int err;

        if (host->retune_now)
                host->retune_now = 0;
        else
                return 0;

        if (!host->need_retune || host->doing_retune || !host->card)
                return 0;

        host->need_retune = 0;

        host->doing_retune = 1;

        if (host->ios.timing == MMC_TIMING_MMC_HS400) {
                err = mmc_hs400_to_hs200(host->card);
                if (err)
                        goto out;

                return_to_hs400 = true;
        }

        err = mmc_execute_tuning(host->card);
        if (err)
                goto out;

        if (return_to_hs400)
                err = mmc_hs200_to_hs400(host->card);
out:
        host->doing_retune = 0;

        return err;
}

static void mmc_retune_timer(struct timer_list *t)
{
        struct mmc_host *host = timer_container_of(host, t, retune_timer);

        mmc_retune_needed(host);
}

static void mmc_of_parse_timing_phase(struct device *dev, const char *prop,
                                      struct mmc_clk_phase *phase)
{
        int degrees[2] = {0};
        int rc;

        rc = device_property_read_u32_array(dev, prop, degrees, 2);
        phase->valid = !rc;
        if (phase->valid) {
                phase->in_deg = degrees[0];
                phase->out_deg = degrees[1];
        }
}

void
mmc_of_parse_clk_phase(struct device *dev, struct mmc_clk_phase_map *map)
{
        mmc_of_parse_timing_phase(dev, "clk-phase-legacy",
                                  &map->phase[MMC_TIMING_LEGACY]);
        mmc_of_parse_timing_phase(dev, "clk-phase-mmc-hs",
                                  &map->phase[MMC_TIMING_MMC_HS]);
        mmc_of_parse_timing_phase(dev, "clk-phase-sd-hs",
                                  &map->phase[MMC_TIMING_SD_HS]);
        mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr12",
                                  &map->phase[MMC_TIMING_UHS_SDR12]);
        mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr25",
                                  &map->phase[MMC_TIMING_UHS_SDR25]);
        mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr50",
                                  &map->phase[MMC_TIMING_UHS_SDR50]);
        mmc_of_parse_timing_phase(dev, "clk-phase-uhs-sdr104",
                                  &map->phase[MMC_TIMING_UHS_SDR104]);
        mmc_of_parse_timing_phase(dev, "clk-phase-uhs-ddr50",
                                  &map->phase[MMC_TIMING_UHS_DDR50]);
        mmc_of_parse_timing_phase(dev, "clk-phase-mmc-ddr52",
                                  &map->phase[MMC_TIMING_MMC_DDR52]);
        mmc_of_parse_timing_phase(dev, "clk-phase-mmc-hs200",
                                  &map->phase[MMC_TIMING_MMC_HS200]);
        mmc_of_parse_timing_phase(dev, "clk-phase-mmc-hs400",
                                  &map->phase[MMC_TIMING_MMC_HS400]);
}
EXPORT_SYMBOL(mmc_of_parse_clk_phase);

/**
 * mmc_of_parse() - parse host's device properties
 * @host: host whose properties should be parsed.
 *
 * To keep the rest of the MMC subsystem unaware of whether DT has been
 * used to instantiate and configure this host instance or not, we
 * parse the properties and set respective generic mmc-host flags and
 * parameters.
 */
int mmc_of_parse(struct mmc_host *host)
{
        struct device *dev = host->parent;
        u32 bus_width, drv_type, cd_debounce_delay_ms;
        int ret;

        if (!dev || !dev_fwnode(dev))
                return 0;

        /* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
        if (device_property_read_u32(dev, "bus-width", &bus_width) < 0) {
                dev_dbg(host->parent,
                        "\"bus-width\" property is missing, assuming 1 bit.\n");
                bus_width = 1;
        }

        switch (bus_width) {
        case 8:
                host->caps |= MMC_CAP_8_BIT_DATA;
                fallthrough;    /* Hosts capable of 8-bit can also do 4 bits */
        case 4:
                host->caps |= MMC_CAP_4_BIT_DATA;
                break;
        case 1:
                break;
        default:
                dev_err(host->parent,
                        "Invalid \"bus-width\" value %u!\n", bus_width);
                return -EINVAL;
        }

        /* f_max is obtained from the optional "max-frequency" property */
        device_property_read_u32(dev, "max-frequency", &host->f_max);

        device_property_read_u32(dev, "max-sd-hs-hz", &host->max_sd_hs_hz);

        /*
         * Configure CD and WP pins. They are both by default active low to
         * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
         * mmc-gpio helpers are used to attach, configure and use them. If
         * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
         * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
         * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
         * is set. If the "non-removable" property is found, the
         * MMC_CAP_NONREMOVABLE capability is set and no card-detection
         * configuration is performed.
         */

        /* Parse Card Detection */

        if (device_property_read_bool(dev, "non-removable")) {
                host->caps |= MMC_CAP_NONREMOVABLE;
        } else {
                if (device_property_read_bool(dev, "cd-inverted"))
                        host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;

                if (device_property_read_u32(dev, "cd-debounce-delay-ms",
                                             &cd_debounce_delay_ms))
                        cd_debounce_delay_ms = 200;

                if (device_property_read_bool(dev, "broken-cd"))
                        host->caps |= MMC_CAP_NEEDS_POLL;

                ret = mmc_gpiod_request_cd(host, "cd", 0, false,
                                           cd_debounce_delay_ms * 1000);
                if (!ret)
                        dev_info(host->parent, "Got CD GPIO\n");
                else if (ret != -ENOENT && ret != -ENOSYS)
                        return ret;
        }

        /* Parse Write Protection */

        if (device_property_read_bool(dev, "wp-inverted"))
                host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;

        ret = mmc_gpiod_request_ro(host, "wp", 0, 0);
        if (!ret)
                dev_info(host->parent, "Got WP GPIO\n");
        else if (ret != -ENOENT && ret != -ENOSYS)
                return ret;

        if (device_property_read_bool(dev, "disable-wp"))
                host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;

        if (device_property_read_bool(dev, "cap-sd-highspeed"))
                host->caps |= MMC_CAP_SD_HIGHSPEED;
        if (device_property_read_bool(dev, "cap-mmc-highspeed"))
                host->caps |= MMC_CAP_MMC_HIGHSPEED;
        if (device_property_read_bool(dev, "sd-uhs-sdr12"))
                host->caps |= MMC_CAP_UHS_SDR12;
        if (device_property_read_bool(dev, "sd-uhs-sdr25"))
                host->caps |= MMC_CAP_UHS_SDR25;
        if (device_property_read_bool(dev, "sd-uhs-sdr50"))
                host->caps |= MMC_CAP_UHS_SDR50;
        if (device_property_read_bool(dev, "sd-uhs-sdr104"))
                host->caps |= MMC_CAP_UHS_SDR104;
        if (device_property_read_bool(dev, "sd-uhs-ddr50"))
                host->caps |= MMC_CAP_UHS_DDR50;
        if (device_property_read_bool(dev, "cap-power-off-card"))
                host->caps |= MMC_CAP_POWER_OFF_CARD;
        if (device_property_read_bool(dev, "cap-mmc-hw-reset"))
                host->caps |= MMC_CAP_HW_RESET;
        if (device_property_read_bool(dev, "cap-sdio-irq"))
                host->caps |= MMC_CAP_SDIO_IRQ;
        if (device_property_read_bool(dev, "full-pwr-cycle"))
                host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
        if (device_property_read_bool(dev, "full-pwr-cycle-in-suspend"))
                host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND;
        if (device_property_read_bool(dev, "keep-power-in-suspend"))
                host->pm_caps |= MMC_PM_KEEP_POWER;
        if (device_property_read_bool(dev, "wakeup-source") ||
            device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */
                host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
        if (device_property_read_bool(dev, "mmc-ddr-3_3v"))
                host->caps |= MMC_CAP_3_3V_DDR;
        if (device_property_read_bool(dev, "mmc-ddr-1_8v"))
                host->caps |= MMC_CAP_1_8V_DDR;
        if (device_property_read_bool(dev, "mmc-ddr-1_2v"))
                host->caps |= MMC_CAP_1_2V_DDR;
        if (device_property_read_bool(dev, "mmc-hs200-1_8v"))
                host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
        if (device_property_read_bool(dev, "mmc-hs200-1_2v"))
                host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
        if (device_property_read_bool(dev, "mmc-hs400-1_8v"))
                host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
        if (device_property_read_bool(dev, "mmc-hs400-1_2v"))
                host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
        if (device_property_read_bool(dev, "mmc-hs400-enhanced-strobe"))
                host->caps2 |= MMC_CAP2_HS400_ES;
        if (device_property_read_bool(dev, "no-sdio"))
                host->caps2 |= MMC_CAP2_NO_SDIO;
        if (device_property_read_bool(dev, "no-sd"))
                host->caps2 |= MMC_CAP2_NO_SD;
        if (device_property_read_bool(dev, "no-mmc"))
                host->caps2 |= MMC_CAP2_NO_MMC;
        if (device_property_read_bool(dev, "no-mmc-hs400"))
                host->caps2 &= ~(MMC_CAP2_HS400_1_8V | MMC_CAP2_HS400_1_2V |
                                 MMC_CAP2_HS400_ES);

        /* Must be after "non-removable" check */
        if (device_property_read_u32(dev, "fixed-emmc-driver-type", &drv_type) == 0) {
                if (host->caps & MMC_CAP_NONREMOVABLE)
                        host->fixed_drv_type = drv_type;
                else
                        dev_err(host->parent,
                                "can't use fixed driver type, media is removable\n");
        }

        host->dsr_req = !device_property_read_u32(dev, "dsr", &host->dsr);
        if (host->dsr_req && (host->dsr & ~0xffff)) {
                dev_err(host->parent,
                        "device tree specified broken value for DSR: 0x%x, ignoring\n",
                        host->dsr);
                host->dsr_req = 0;
        }

        device_property_read_u32(dev, "post-power-on-delay-ms",
                                 &host->ios.power_delay_ms);

        return mmc_pwrseq_alloc(host);
}

EXPORT_SYMBOL(mmc_of_parse);

/**
 * mmc_of_parse_voltage - return mask of supported voltages
 * @host: host whose properties should be parsed.
 * @mask: mask of voltages available for MMC/SD/SDIO
 *
 * Parse the "voltage-ranges" property, returning zero if it is not
 * found, negative errno if the voltage-range specification is invalid,
 * or one if the voltage-range is specified and successfully parsed.
 */
int mmc_of_parse_voltage(struct mmc_host *host, u32 *mask)
{
        const char *prop = "voltage-ranges";
        struct device *dev = host->parent;
        u32 *voltage_ranges;
        int num_ranges, i;
        int ret;

        if (!device_property_present(dev, prop)) {
                dev_dbg(dev, "%s unspecified\n", prop);
                return 0;
        }

        ret = device_property_count_u32(dev, prop);
        if (ret < 0)
                return ret;

        num_ranges = ret / 2;
        if (!num_ranges) {
                dev_err(dev, "%s empty\n", prop);
                return -EINVAL;
        }

        voltage_ranges = kcalloc(2 * num_ranges, sizeof(*voltage_ranges), GFP_KERNEL);
        if (!voltage_ranges)
                return -ENOMEM;

        ret = device_property_read_u32_array(dev, prop, voltage_ranges, 2 * num_ranges);
        if (ret) {
                kfree(voltage_ranges);
                return ret;
        }

        for (i = 0; i < num_ranges; i++) {
                const int j = i * 2;
                u32 ocr_mask;

                ocr_mask = mmc_vddrange_to_ocrmask(voltage_ranges[j + 0],
                                                   voltage_ranges[j + 1]);
                if (!ocr_mask) {
                        dev_err(dev, "range #%d in %s is invalid\n", i, prop);
                        kfree(voltage_ranges);
                        return -EINVAL;
                }
                *mask |= ocr_mask;
        }

        kfree(voltage_ranges);

        return 1;
}
EXPORT_SYMBOL(mmc_of_parse_voltage);

/**
 * mmc_first_nonreserved_index() - get the first index that is not reserved
 */
static int mmc_first_nonreserved_index(void)
{
        int max;

        max = of_alias_get_highest_id("mmc");
        if (max < 0)
                return 0;

        return max + 1;
}

/**
 *      mmc_alloc_host - initialise the per-host structure.
 *      @extra: sizeof private data structure
 *      @dev: pointer to host device model structure
 *
 *      Initialise the per-host structure.
 */
struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
{
        int index;
        struct mmc_host *host;
        int alias_id, min_idx, max_idx;

        host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
        if (!host)
                return NULL;

        /* scanning will be enabled when we're ready */
        host->rescan_disable = 1;

        alias_id = of_alias_get_id(dev->of_node, "mmc");
        if (alias_id >= 0) {
                index = alias_id;
        } else {
                min_idx = mmc_first_nonreserved_index();
                max_idx = 0;

                index = ida_alloc_range(&mmc_host_ida, min_idx, max_idx - 1,
                                        GFP_KERNEL);
                if (index < 0) {
                        kfree(host);
                        return NULL;
                }
        }

        host->index = index;

        dev_set_name(&host->class_dev, "mmc%d", host->index);
        host->ws = wakeup_source_register(NULL, dev_name(&host->class_dev));

        host->parent = dev;
        host->class_dev.parent = dev;
        host->class_dev.class = &mmc_host_class;
        device_initialize(&host->class_dev);
        device_enable_async_suspend(&host->class_dev);

        if (mmc_gpio_alloc(host)) {
                put_device(&host->class_dev);
                return NULL;
        }

        spin_lock_init(&host->lock);
        init_waitqueue_head(&host->wq);
        INIT_DELAYED_WORK(&host->detect, mmc_rescan);
        INIT_WORK(&host->sdio_irq_work, sdio_irq_work);
        timer_setup(&host->retune_timer, mmc_retune_timer, 0);

        INIT_WORK(&host->supply.uv_work, mmc_undervoltage_workfn);

        /*
         * By default, hosts do not support SGIO or large requests.
         * They have to set these according to their abilities.
         */
        host->max_segs = 1;
        host->max_seg_size = PAGE_SIZE;

        host->max_req_size = PAGE_SIZE;
        host->max_blk_size = 512;
        host->max_blk_count = PAGE_SIZE / 512;

        host->fixed_drv_type = -EINVAL;
        host->ios.power_delay_ms = 10;
        host->ios.power_mode = MMC_POWER_UNDEFINED;

        return host;
}

EXPORT_SYMBOL(mmc_alloc_host);

static void devm_mmc_host_release(struct device *dev, void *res)
{
        mmc_free_host(*(struct mmc_host **)res);
}

struct mmc_host *devm_mmc_alloc_host(struct device *dev, int extra)
{
        struct mmc_host **dr, *host;

        dr = devres_alloc(devm_mmc_host_release, sizeof(*dr), GFP_KERNEL);
        if (!dr)
                return NULL;

        host = mmc_alloc_host(extra, dev);
        if (!host) {
                devres_free(dr);
                return NULL;
        }

        *dr = host;
        devres_add(dev, dr);

        return host;
}
EXPORT_SYMBOL(devm_mmc_alloc_host);

static int mmc_validate_host_caps(struct mmc_host *host)
{
        struct device *dev = host->parent;
        u32 caps = host->caps, caps2 = host->caps2;

        if (caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) {
                dev_warn(dev, "missing ->enable_sdio_irq() ops\n");
                return -EINVAL;
        }

        if (caps2 & (MMC_CAP2_HS400_ES | MMC_CAP2_HS400) &&
            !(caps & MMC_CAP_8_BIT_DATA) && !(caps2 & MMC_CAP2_NO_MMC)) {
                dev_warn(dev, "drop HS400 support since no 8-bit bus\n");
                host->caps2 = caps2 & ~MMC_CAP2_HS400_ES & ~MMC_CAP2_HS400;
        }

        return 0;
}

/**
 *      mmc_add_host - initialise host hardware
 *      @host: mmc host
 *
 *      Register the host with the driver model. The host must be
 *      prepared to start servicing requests before this function
 *      completes.
 */
int mmc_add_host(struct mmc_host *host)
{
        int err;

        err = mmc_validate_host_caps(host);
        if (err)
                return err;

        err = device_add(&host->class_dev);
        if (err)
                return err;

        led_trigger_register_simple(dev_name(&host->class_dev), &host->led);

        mmc_add_host_debugfs(host);

        mmc_start_host(host);
        return 0;
}

EXPORT_SYMBOL(mmc_add_host);

/**
 *      mmc_remove_host - remove host hardware
 *      @host: mmc host
 *
 *      Unregister and remove all cards associated with this host,
 *      and power down the MMC bus. No new requests will be issued
 *      after this function has returned.
 */
void mmc_remove_host(struct mmc_host *host)
{
        mmc_stop_host(host);

        mmc_remove_host_debugfs(host);

        device_del(&host->class_dev);

        led_trigger_unregister_simple(host->led);
}

EXPORT_SYMBOL(mmc_remove_host);

/**
 *      mmc_free_host - free the host structure
 *      @host: mmc host
 *
 *      Free the host once all references to it have been dropped.
 */
void mmc_free_host(struct mmc_host *host)
{
        cancel_delayed_work_sync(&host->detect);
        mmc_pwrseq_free(host);
        put_device(&host->class_dev);
}

EXPORT_SYMBOL(mmc_free_host);