root/drivers/mmc/core/bus.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 *  linux/drivers/mmc/core/bus.c
 *
 *  Copyright (C) 2003 Russell King, All Rights Reserved.
 *  Copyright (C) 2007 Pierre Ossman
 *
 *  MMC card bus driver model
 */

#include <linux/export.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/stat.h>
#include <linux/of.h>
#include <linux/pm_runtime.h>
#include <linux/sysfs.h>

#include <linux/mmc/card.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>

#include "core.h"
#include "card.h"
#include "host.h"
#include "sdio_cis.h"
#include "bus.h"

#define to_mmc_driver(d)        container_of(d, struct mmc_driver, drv)

static ssize_t type_show(struct device *dev,
        struct device_attribute *attr, char *buf)
{
        struct mmc_card *card = mmc_dev_to_card(dev);

        switch (card->type) {
        case MMC_TYPE_MMC:
                return sysfs_emit(buf, "MMC\n");
        case MMC_TYPE_SD:
                return sysfs_emit(buf, "SD\n");
        case MMC_TYPE_SDIO:
                return sysfs_emit(buf, "SDIO\n");
        case MMC_TYPE_SD_COMBO:
                return sysfs_emit(buf, "SDcombo\n");
        default:
                return -EFAULT;
        }
}
static DEVICE_ATTR_RO(type);

static struct attribute *mmc_dev_attrs[] = {
        &dev_attr_type.attr,
        NULL,
};
ATTRIBUTE_GROUPS(mmc_dev);

static int
mmc_bus_uevent(const struct device *dev, struct kobj_uevent_env *env)
{
        const struct mmc_card *card = mmc_dev_to_card(dev);
        const char *type;
        unsigned int i;
        int retval = 0;

        switch (card->type) {
        case MMC_TYPE_MMC:
                type = "MMC";
                break;
        case MMC_TYPE_SD:
                type = "SD";
                break;
        case MMC_TYPE_SDIO:
                type = "SDIO";
                break;
        case MMC_TYPE_SD_COMBO:
                type = "SDcombo";
                break;
        default:
                type = NULL;
        }

        if (type) {
                retval = add_uevent_var(env, "MMC_TYPE=%s", type);
                if (retval)
                        return retval;
        }

        if (mmc_card_sdio(card) || mmc_card_sd_combo(card)) {
                retval = add_uevent_var(env, "SDIO_ID=%04X:%04X",
                                        card->cis.vendor, card->cis.device);
                if (retval)
                        return retval;

                retval = add_uevent_var(env, "SDIO_REVISION=%u.%u",
                                        card->major_rev, card->minor_rev);
                if (retval)
                        return retval;

                for (i = 0; i < card->num_info; i++) {
                        retval = add_uevent_var(env, "SDIO_INFO%u=%s", i+1, card->info[i]);
                        if (retval)
                                return retval;
                }
        }

        /*
         * SDIO (non-combo) cards are not handled by mmc_block driver and do not
         * have accessible CID register which used by mmc_card_name() function.
         */
        if (mmc_card_sdio(card))
                return 0;

        retval = add_uevent_var(env, "MMC_NAME=%s", mmc_card_name(card));
        if (retval)
                return retval;

        /*
         * Request the mmc_block device.  Note: that this is a direct request
         * for the module it carries no information as to what is inserted.
         */
        retval = add_uevent_var(env, "MODALIAS=mmc:block");

        return retval;
}

static int mmc_bus_probe(struct device *dev)
{
        struct mmc_driver *drv = to_mmc_driver(dev->driver);
        struct mmc_card *card = mmc_dev_to_card(dev);

        return drv->probe(card);
}

static void mmc_bus_remove(struct device *dev)
{
        struct mmc_driver *drv = to_mmc_driver(dev->driver);
        struct mmc_card *card = mmc_dev_to_card(dev);

        drv->remove(card);
}

static void mmc_bus_shutdown(struct device *dev)
{
        struct mmc_driver *drv = to_mmc_driver(dev->driver);
        struct mmc_card *card = mmc_dev_to_card(dev);
        struct mmc_host *host = card->host;
        int ret;

        if (dev->driver && drv->shutdown)
                drv->shutdown(card);

        __mmc_stop_host(host);

        if (host->bus_ops->shutdown) {
                ret = host->bus_ops->shutdown(host);
                if (ret)
                        pr_warn("%s: error %d during shutdown\n",
                                mmc_hostname(host), ret);
        }
}

#ifdef CONFIG_PM_SLEEP
static int mmc_bus_suspend(struct device *dev)
{
        struct mmc_card *card = mmc_dev_to_card(dev);
        struct mmc_host *host = card->host;
        int ret;

        ret = pm_generic_suspend(dev);
        if (ret)
                return ret;

        ret = host->bus_ops->suspend(host);
        if (ret)
                pm_generic_resume(dev);

        return ret;
}

static int mmc_bus_resume(struct device *dev)
{
        struct mmc_card *card = mmc_dev_to_card(dev);
        struct mmc_host *host = card->host;
        int ret;

        ret = host->bus_ops->resume(host);
        if (ret)
                pr_warn("%s: error %d during resume (card was removed?)\n",
                        mmc_hostname(host), ret);

        ret = pm_generic_resume(dev);
        return ret;
}
#endif

#ifdef CONFIG_PM
static int mmc_runtime_suspend(struct device *dev)
{
        struct mmc_card *card = mmc_dev_to_card(dev);
        struct mmc_host *host = card->host;

        return host->bus_ops->runtime_suspend(host);
}

static int mmc_runtime_resume(struct device *dev)
{
        struct mmc_card *card = mmc_dev_to_card(dev);
        struct mmc_host *host = card->host;

        return host->bus_ops->runtime_resume(host);
}
#endif /* !CONFIG_PM */

static const struct dev_pm_ops mmc_bus_pm_ops = {
        SET_RUNTIME_PM_OPS(mmc_runtime_suspend, mmc_runtime_resume, NULL)
        SET_SYSTEM_SLEEP_PM_OPS(mmc_bus_suspend, mmc_bus_resume)
};

static const struct bus_type mmc_bus_type = {
        .name           = "mmc",
        .dev_groups     = mmc_dev_groups,
        .uevent         = mmc_bus_uevent,
        .probe          = mmc_bus_probe,
        .remove         = mmc_bus_remove,
        .shutdown       = mmc_bus_shutdown,
        .pm             = &mmc_bus_pm_ops,
};

int mmc_register_bus(void)
{
        return bus_register(&mmc_bus_type);
}

void mmc_unregister_bus(void)
{
        bus_unregister(&mmc_bus_type);
}

/**
 *      mmc_register_driver - register a media driver
 *      @drv: MMC media driver
 */
int mmc_register_driver(struct mmc_driver *drv)
{
        drv->drv.bus = &mmc_bus_type;
        return driver_register(&drv->drv);
}

EXPORT_SYMBOL(mmc_register_driver);

/**
 *      mmc_unregister_driver - unregister a media driver
 *      @drv: MMC media driver
 */
void mmc_unregister_driver(struct mmc_driver *drv)
{
        drv->drv.bus = &mmc_bus_type;
        driver_unregister(&drv->drv);
}

EXPORT_SYMBOL(mmc_unregister_driver);

static void mmc_release_card(struct device *dev)
{
        struct mmc_card *card = mmc_dev_to_card(dev);

        sdio_free_common_cis(card);

        kfree(card->info);

        kfree(card);
}

/*
 * Allocate and initialise a new MMC card structure.
 */
struct mmc_card *mmc_alloc_card(struct mmc_host *host, const struct device_type *type)
{
        struct mmc_card *card;

        card = kzalloc_obj(struct mmc_card);
        if (!card)
                return ERR_PTR(-ENOMEM);

        card->host = host;

        device_initialize(&card->dev);

        card->dev.parent = mmc_classdev(host);
        card->dev.bus = &mmc_bus_type;
        card->dev.release = mmc_release_card;
        card->dev.type = type;

        return card;
}

/*
 * Register a new MMC card with the driver model.
 */
int mmc_add_card(struct mmc_card *card)
{
        int ret;
        const char *type;
        const char *speed_mode = "";
        const char *uhs_bus_speed_mode = "";
        static const char *const uhs_speeds[] = {
                [UHS_SDR12_BUS_SPEED] = "SDR12 ",
                [UHS_SDR25_BUS_SPEED] = "SDR25 ",
                [UHS_SDR50_BUS_SPEED] = "SDR50 ",
                [UHS_SDR104_BUS_SPEED] = "SDR104 ",
                [UHS_DDR50_BUS_SPEED] = "DDR50 ",
        };


        dev_set_name(&card->dev, "%s:%04x", mmc_hostname(card->host), card->rca);
        dev_set_removable(&card->dev,
                          mmc_card_is_removable(card->host) ?
                          DEVICE_REMOVABLE : DEVICE_FIXED);

        switch (card->type) {
        case MMC_TYPE_MMC:
                type = "MMC";
                break;
        case MMC_TYPE_SD:
                type = "SD";
                if (mmc_card_blockaddr(card)) {
                        if (mmc_card_ult_capacity(card))
                                type = "SDUC";
                        else if (mmc_card_ext_capacity(card))
                                type = "SDXC";
                        else
                                type = "SDHC";
                }
                break;
        case MMC_TYPE_SDIO:
                type = "SDIO";
                break;
        case MMC_TYPE_SD_COMBO:
                type = "SD-combo";
                if (mmc_card_blockaddr(card))
                        type = "SDHC-combo";
                break;
        default:
                type = "?";
                break;
        }

        if (mmc_card_hs(card))
                speed_mode = "high speed ";
        else if (mmc_card_uhs(card))
                speed_mode = "UHS-I speed ";
        else if (mmc_card_uhs2(card->host))
                speed_mode = "UHS-II speed ";
        else if (mmc_card_ddr52(card))
                speed_mode = "high speed DDR ";
        else if (mmc_card_hs200(card))
                speed_mode = "HS200 ";
        else if (mmc_card_hs400es(card))
                speed_mode = "HS400 Enhanced strobe ";
        else if (mmc_card_hs400(card))
                speed_mode = "HS400 ";

        if (mmc_card_uhs(card) &&
                (card->sd_bus_speed < ARRAY_SIZE(uhs_speeds)))
                uhs_bus_speed_mode = uhs_speeds[card->sd_bus_speed];

        if (mmc_host_is_spi(card->host))
                pr_info("%s: new %s%s card on SPI\n",
                        mmc_hostname(card->host), speed_mode, type);
        else
                pr_info("%s: new %s%s%s card at address %04x\n",
                        mmc_hostname(card->host), speed_mode,
                        uhs_bus_speed_mode, type, card->rca);

        mmc_add_card_debugfs(card);
        card->dev.of_node = mmc_of_find_child_device(card->host, 0);

        device_enable_async_suspend(&card->dev);

        ret = device_add(&card->dev);
        if (ret)
                return ret;

        mmc_card_set_present(card);

        /*
         * Register for undervoltage notification if the card supports
         * power-off notification, enabling emergency shutdowns.
         */
        if (mmc_card_mmc(card) &&
            card->ext_csd.power_off_notification == EXT_CSD_POWER_ON)
                mmc_regulator_register_undervoltage_notifier(card->host);

        return 0;
}

/*
 * Unregister a new MMC card with the driver model, and
 * (eventually) free it.
 */
void mmc_remove_card(struct mmc_card *card)
{
        struct mmc_host *host = card->host;

        if (mmc_card_present(card))
                mmc_regulator_unregister_undervoltage_notifier(host);

        mmc_remove_card_debugfs(card);

        if (mmc_card_present(card)) {
                if (mmc_host_is_spi(card->host)) {
                        pr_info("%s: SPI card removed\n",
                                mmc_hostname(card->host));
                } else {
                        pr_info("%s: card %04x removed\n",
                                mmc_hostname(card->host), card->rca);
                }
                device_del(&card->dev);
                of_node_put(card->dev.of_node);
        }

        if (host->cqe_enabled) {
                host->cqe_ops->cqe_disable(host);
                host->cqe_enabled = false;
        }

        put_device(&card->dev);
}